DISHWASHER AND METHOD FOR CONTROLLING THE DISHWASHER

Abstract

A dishwasher according to an embodiment of the disclosure relates to providing a control method for determining whether a filter is clogged. A dishwasher according to an embodiment of the disclosure may comprise a tub, a sump assembly disposed under the tub and storing washing water, a circulation pump pumping and circulating the washing water stored in the sump assembly, at least one jet device jetting the washing water pumped by the circulation pump into the tub, a filter disposed under the tub and filtering a foreign object flowing inside the tub, a current sensor detecting a driving current input to the circulation pump, a vibration sensor detecting a vibration signal of the tub generated by driving of the circulation pump, and a controller configured to detect whether the filter is clogged based on information obtained from the current sensor and the vibration sensor.

Claims

1. A dishwasher comprising: a tub; a sump assembly configured to store washing water; a circulation pump that is drivable via a driving current to pump the washing water stored in the sump assembly; at least one jet device configured to jet the washing water pumped by the circulation pump into the tub; a filter configured to filter a foreign object from the washing water; a current sensor configured to sense the driving current and to produce a corresponding sensed value; a vibration sensor configured to sense vibration of the tub and to produce a corresponding sensed value; and a controller configured to: obtain a first natural frequency of the tub based on the sensed value produced by the vibration sensor, obtain a second natural frequency of the tub based on the sensed value produced by the vibration sensor, in response to the sensed value produced by the current sensor indicating that the driving current is less than a reference current, and determine that the filter is in a clogged state based on a variation in the second natural frequency with respect to the first natural frequency exceeding a preset threshold range.

2. The dishwasher of claim 1, wherein the sump assembly is under the tub, and the vibration sensor is under the sump assembly.

3. The dishwasher of claim 2, wherein the vibration sensor is adjacent to the circulation pump.

4. The dishwasher of claim 1, wherein the vibration sensed by the vibration sensor corresponds to an amount of the washing water collected in the tub.

5. The dishwasher of claim 1, wherein the vibration sensor includes an accelerometer or a strain gauge.

6. The dishwasher of claim 1, wherein the first natural frequency is a natural frequency of the tub obtained in response to initiation of a water supply process included in a washing cycle, and the second natural frequency is a natural frequency of the tub after completion of water supply process.

7. The dishwasher of claim 1, further comprising: an actuator on a surface of the tub and configured to vibrate the tub, wherein the controller is configured to obtain the first natural frequency and the second natural frequency from the vibration sensor in response to the vibration of the tub by the actuator.

8. The dishwasher of claim 1, wherein the controller is configured to, when a difference between the first natural frequency and the second natural frequency is within the preset threshold range, determine that a water level of the washing water stored in the tub is lower than a reference water level.

9. The dishwasher of claim 8, wherein the controller is configured to, when a number of times in which the washing water is supplied to the tub is less than a threshold number, control the circulation pump to supply a predetermined volume of the washing water to the tub.

10. The dishwasher of claim 8, wherein the reference water level is set to a water level at which the washing water collected in the tub reaches an uppermost end of the sump assembly.

11. The dishwasher of claim 1, further comprising: a display, wherein the controller is configured to, when the filter is determined to be in the clogged state, display information indicating the clogged state of the filter on the display.

12. The dishwasher of claim 1, further comprising: a communication unit configured to wirelessly communicate with an external device, wherein the controller is configured to, when the filter is determined to be in the clogged state, transfer guide information instructing management of the filter to the external device through the communication unit.

13. A method for controlling a dishwasher that includes a tub, a sump assembly configured to store washing water, a circulation pump that is drivable via a driving current to pump the washing water stored in the sump assembly, at least one jet device configured to jet the washing water pumped by the circulation pump into the tub, a filter configured to filter a foreign object from the washing water, a current sensor configured to sense the driving current and to produce a corresponding sensed value, and a vibration sensor configured to sense vibration of the tub and to produce a corresponding sensed value, the method comprising: obtaining a first natural frequency of the tub based on the sensed value produced by the vibration sensor; obtaining a second natural frequency of the tub based on the sensed value produced by the vibration sensor, in response to the sensed value produced by the current sensor indicating that the driving current is less than a reference current; and determining that the filter is in a clogged state based on a variation in the second natural frequency with respect to the first natural frequency exceeding a preset threshold range.

14. The method of claim 13, wherein the vibration sensed by the vibration sensor corresponds to an amount of the washing water collected in the tub.

15. The method of claim 13, wherein the first natural frequency is a natural frequency of the tub obtained in response to initiation of a water supply process included in a washing cycle, and the second natural frequency is a natural frequency of the tub after completion of the water supply process.

16. The method of claim 13, further comprising: when a difference between the first natural frequency and the second natural frequency is within the preset threshold range, determining that a water level of the washing water stored in the tub is lower than a reference water level.

17. The method of claim 16, further comprising: when a number of times in which the washing water is supplied to the tub is less than a threshold number, controlling the circulation pump to supply a predetermined volume of the washing water to the tub.

18. The method of claim 16, wherein the reference water level is set to a water level at which the washing water collected in the tub reaches an uppermost end of the sump assembly.

19. The method of claim 13, further comprising: when the filter is determined to be in the clogged state, displaying information indicating the clogging state of the filter on a display.

20. The method of claim 13, further comprising: when the filter is determined to be in the clogged state, transferring guide information instructing management of the filter to an external device.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0014] The above and other aspects, features, and advantages of certain embodiments of the disclosure will be more apparent from the following description taken in conjunction with the accompanying drawings, in which:

[0015] FIG. 1 is a perspective view schematically illustrating a dishwasher according to an embodiment of the disclosure;

[0016] FIG. 2 is a side cross-sectional view illustrating a dishwasher according to an embodiment of the disclosure;

[0017] FIG. 3 illustrates a lower portion of a washing chamber of a dishwasher according to an embodiment of the disclosure;

[0018] FIG. 4A is a perspective view illustrating a sump assembly included in a dishwasher according to an embodiment of the disclosure;

[0019] FIG. 4B is an exploded perspective view illustrating a sump assembly included in a dishwasher according to an embodiment of the disclosure;

[0020] FIG. 5 is a bottom view illustrating a sump assembly as viewed upward according to an embodiment of the disclosure;

[0021] FIG. 6 is a graph for selecting an optimal position of a vibration sensor installed in a sump assembly according to an embodiment of the disclosure;

[0022] FIG. 7 is a block diagram illustrating a configuration of a dishwasher according to an embodiment of the disclosure;

[0023] FIG. 8 is a view schematically illustrating a process of calculating a natural frequency in response to a vibration generated in a tub by a dishwasher according to an embodiment of the disclosure;

[0024] FIG. 9 is a flowchart illustrating control for determining a clogging state of a filter by a dishwasher according to an embodiment of the disclosure;

[0025] FIG. 10 is a flowchart illustrating control for determining a clogging state of a filter by a dishwasher according to an embodiment of the disclosure;

[0026] FIG. 11 is a graph illustrating a driving current input to a circulation pump for each driving rpm of the circulation pump according to filter performance according to an embodiment of the disclosure;

[0027] FIG. 12 is a graph illustrating a natural frequency of a tub for each driving rpm of a circulation pump according to the volume of washing water stored in the tub according to an embodiment of the disclosure;

[0028] FIG. 13 is a contour graph schematically illustrating vibration characteristics of a tub in response to the water level of washing water stored in the tub according to an embodiment of the disclosure;

[0029] FIG. 14 schematically illustrates a smart home system according to an embodiment of the disclosure;

[0030] FIG. 15 is a signaling view schematically illustrating a process of transferring guide information for instructing management of a filter between a dishwasher, a hub device, and an external device according to an embodiment of the disclosure;

[0031] FIG. 16 illustrates an input/output unit of a dishwasher according to an embodiment of the disclosure;

[0032] FIG. 17 illustrates an embodiment of displaying guide information instructing management of a filter of dishwasher by an external device according to an embodiment of the disclosure;

[0033] FIG. 18 illustrates a first user interface of guide information displayed on an external device according to an embodiment of the disclosure; and

[0034] FIG. 19 illustrates a second user interface of guide information displayed on an external device according to an embodiment of the disclosure.

DETAILED DESCRIPTION

[0035] An embodiment of the disclosure and terms used therein are not intended to limit the technical features described in the disclosure to specific embodiments, and should be understood to include various modifications, equivalents, or substitutes of the embodiment. With regard to the description of the drawings, similar reference numerals may be used to refer to similar or related elements. It is to be understood that a singular form of a noun corresponding to an item may include one or more of the things, unless the relevant context clearly indicates otherwise. As used herein, each of such phrases as A or B, at least one of A and B, at least one of A or B, A, B, or C, at least one of A, B, and C, and at least one of A, B, or C, may include all possible combinations of the items enumerated together in a corresponding one of the phrases. As used herein, such terms as 1st and 2nd, or first and second may be used to simply distinguish a corresponding component from another, and does not limit the components in other aspect (e.g., importance or order).

[0036] In the disclosure, hereinafter, based on when the door (e.g., the door 11 of FIG. 1) of the dishwasher (e.g., the dishwasher 1 of FIG. 1) is viewed from the front, the front of the dishwasher 1 where the door 11 is disposed may be defined as a +x-axis direction, the rear of the dishwasher 1 as a x-axis direction, the right side of the dishwasher 1 as a +y-axis direction, the left side as a y-axis direction, and the upper side of the dishwasher 1 as a +z-axis direction, and the lower side as a z-axis direction.

[0037] However, in the disclosure, the terms front and rear direction, left and right direction, and upper and lower direction to be used below may be used with respect to the illustrated drawings, and the shape and position of each component are not limited thereto.

[0038] According to an embodiment, each component (e.g., a module or a program) of the above-described components may include a single entity or multiple entities. Some of the plurality of entities may be separately disposed in different components.

[0039] Further, in some of the accompanying drawings, the dimensions of some components may be exaggerated rather than being shown at the actual scale to help understand the disclosure.

[0040] FIG. 1 is a perspective view illustrating a dishwasher 1 according to an embodiment of the disclosure.

[0041] FIG. 2 is a side cross-sectional view illustrating a dishwasher 1 according to an embodiment of the disclosure.

[0042] FIG. 3 illustrates a lower portion of a washing chamber C of a dishwasher 1 according to an embodiment of the disclosure.

[0043] Referring to FIGS. 1 to 3, the dishwasher 1 may include a main body 10 forming the exterior. The dishwasher 1 may further include a tub 12 provided inside the main body 10. The tub 12 may be provided substantially in a box shape. One surface of the tub 12 may be open. For example, the front surface of the tub 12 may be formed to be open. The open surface of the tub 12 may be referred to as an opening 12a.

[0044] According to an embodiment, the dishwasher 1 may include a door 11 disposed to open and close the opening 12a of the tub 12. The door 11 may be coupled to the main body 10 to open and close the opening 12a of the tub 12. The door 11 may be coupled to one side of the main body 10 and disposed to be rotatable with respect to the coupled side. For example, the door 11 may be hinge-coupled to one side end (e.g., a lower side) of the main body 10.

[0045] According to an embodiment, the dishwasher 1 may include a storage container disposed inside the tub 12 to store dishes. The storage container may include, e.g., a plurality of baskets 51, 52, and 53.

[0046] According to an embodiment, the plurality of baskets 51, 52, and 53 may include a second basket 52 positioned approximately in the middle in the height direction of the dishwasher 1 and a first basket 51 positioned below the second basket 52 in the dishwasher 1. The second basket 52 may be disposed to be supported by a second guide rack 13b, and the first basket 51 may be disposed to be supported by a first guide rack 13a.

[0047] According to an embodiment, the first guide rack 13a and the second guide rack 13b may be disposed to be slidable toward the opening 12a of the tub 12. For example, each of the first guide rack 13a and the second guide rack 13b may be slidably disposed on two opposite side surfaces 12d of the tub 12.

[0048] According to an embodiment, the storage container may include a third basket 53 positioned at an upper portion in the height direction of the dishwasher 1. The third basket 53 may be formed, e.g., in the form of a rack assembly.

[0049] According to an embodiment, relatively large dishes or cooking tools may be stored in the first and second baskets 51 and 52, and relatively small dishes or cooking tools may be stored in the third basket 53. However, the type of dishes that may be stored in the first to third baskets 51, 52, and 53 is not limited.

[0050] According to an embodiment, the dishwasher 1 may be used in a state in which some of the first to third baskets 51, 52, and 53 are removed. For example, in a state in which the second basket 52 is removed, the dishwasher 1 may be used in a state in which relatively large (e.g., high) dishes or cooking tools are stored in the first basket 51.

[0051] According to an embodiment, the dishwasher 1 may include a sump assembly 100 for storing washing water. The dishwasher 1 may include a washing chamber C, which is a space formed by the inside of the tub 12. The washing chamber C may be defined as an inner space of the tub 12 formed by the side surface 12d, front surface, rear surface, and lower surface of the tub 12, and the sump assembly 100 communicating with the lower surface.

[0052] According to an embodiment, the dishwasher 1 may further include jet device 41, 42, and 43 provided to jet washing water. For example, the jet device 41, 42, and 43 may include a first jet nozzle 41 disposed under the lower basket 51 in the height direction of the dishwasher 1, a second jet nozzle 42 disposed under the second basket 52 in the height direction of the dishwasher 1, and a third jet nozzle 43 disposed above the third basket 53 in the height direction of the dishwasher 1. The first jet nozzle 41 may be disposed to be rotatable about a first rotation shaft 41a, the second jet nozzle 42 may be disposed to be rotatable about a second rotation shaft 41b, and the third jet nozzle 43 may be disposed to be rotatable about a third rotation shaft 41c.

[0053] According to an embodiment, the direction of the washing water jetted from the first jet nozzle 41 in the horizontal direction may be changed by a switching device (not illustrated) disposed inside the washing chamber C. The third jet nozzle 43 may jet washing water toward the dishes stored in the first to third baskets 51, 52, and 53. The second jet nozzle 42 may jet washing water toward the dishes stored in the second and third baskets 52 and 53.

[0054] According to an embodiment, the first jet nozzle 41 may be disposed on the lower surface of the tub 12. For example, the first jet nozzle 41 may be disposed to be fixed to the sump assembly 100.

[0055] According to an embodiment, the dishwasher 1 may include a circulation pump 30 for pumping water stored in the sump assembly 100 to the first to third jet nozzles 41, 42, and 43. The circulation pump 30 may be connected to an alternating device 80, and the circulation pump 30 may supply washing water to the first jet nozzle 41 through the alternating device 80, or may move the washing water upward by a duct 90 and supply the washing water to the second jet nozzle 42 and/or the third jet nozzle 43.

[0056] According to an embodiment, the circulation pump 30 may be driven by a circulation pump motor (not shown) disposed inside the circulation pump 30. The circulation pump motor may be implemented as, e.g., a brushless DC motor (BLDC motor). As the circulation pump motor is implemented as a brushless motor, the circulation pump 30 may be driven at a speed corresponding to the driving rotational speed (driving rpm) of the circulation pump motor.

[0057] According to an embodiment, the alternating device 80 may be connected to the first jet nozzle 41 through a connector 81. The alternating device 80 may provide washing water to at least one of the connector 81 and the duct 90.

[0058] According to an embodiment, the dishwasher 1 may include a machine room L disposed under the tub 12. The machine room L may be formed by the lower frame 160. The circulation pump 30, the alternating device 80, and the sump assembly 100 may be disposed inside the machine room L.

[0059] According to an embodiment, the dishwasher 1 may include a drain hose 20 for draining the washing water remaining inside the tub 12. The drain hose 20 may be connected to the sump assembly 100. The drain hose 20 may provide a passage through which washing water stored in the sump assembly 100 is to be drained to the outside of the dishwasher 1.

[0060] According to an embodiment, the tub 12 may include a drain pump 40 that pumps the washing water collected inside the tub 12 to be drained to the outside through the drain hose 20. For example, when the drain process begins, the drain pump 40 is driven, and the drain pump 40 may drain the washing water collected in the tub 12 through the drain hose 20.

[0061] According to an embodiment, at least some of the washing water collected in the sump assembly 100 may be purified by a filter inside the sump assembly 100 and then circulated back into the washing chamber C by the circulation pump 30.

[0062] According to an embodiment, the dishwasher 1 may include an input/output unit (user interface) 200. The input/output unit 200 may include an input unit (user input) (e.g., the input unit 210 of FIG. 7) for selecting the operation of the dishwasher 1, and an output unit (user output) (e.g., the output unit 220 of FIG. 7) for outputting operation information and/or state information about the dishwasher 1. The input/output unit 200 may have the input unit 210 and the output unit 220 integrally implemented, or implemented as independent components.

[0063] According to an embodiment, the input unit 210 may be implemented as a button for receiving the user input by a physical press or touch. The input unit 210 may receive, e.g., information about the course where the dishwasher 1 will perform washing, or the user input for a time when the dishwasher 1 will perform washing. The input unit 210 may receive, e.g., the user input for opening the door 11 of the dishwasher 1.

[0064] According to an embodiment, the output unit 220 may output operation information and/or state information about the dishwasher 1. The output unit 220 may be implemented as a display for visually outputting the operation information and/or the state information about the dishwasher 1, or may be implemented as a speaker for audibly outputting the operation information and/or the state information about the dishwasher 1.

[0065] According to an embodiment, when the dishwasher 1 starts the washing cycle, the output unit 220 may output information about the running time of the remaining washing cycle in real-time. The output unit 220 may output information about the washing course currently being performed, e.g., when the dishwasher 1 performs the washing process. The output unit 220 may output, e.g., information indicating that the filter 101 of the dishwasher 1 is in a clogged state.

[0066] According to an embodiment, the input/output unit 200 may have an input unit 210 and an output unit 220 integrally configured. For example, the input/output unit 200 may be implemented as a touch screen panel (TSP), receive an input by the user's touch, and visually display the operation information and/or state information about the dishwasher 1.

[0067] According to an embodiment, when the input/output unit 200 is implemented as a display panel, the input/output unit 200 may be positioned on one side of the main body 10 or the door 11. For example, the input/output unit 200 may be positioned in either the first area A1 positioned at the upper end of the front surface of the main body 10 or the second area A2 positioned at the upper end of the door 11.

[0068] FIG. 4A is a perspective view illustrating a sump assembly (e.g., a sump assembly 100 of FIG. 3) included in a dishwasher (e.g., a dishwasher 1 of FIG. 1) according to an embodiment of the disclosure.

[0069] FIG. 4B is an exploded perspective view illustrating a sump assembly 100 included in a dishwasher 1 according to an embodiment of the disclosure.

[0070] FIGS. 4A and 4B may be selectively combined with the embodiment of FIGS. 1 to 3. Referring to FIGS. 4A and 4B, the sump assembly 100 may be disposed inside a washing

[0071] chamber (e.g., the washing chamber C of FIG. 2) to store washing water. The bottom surface (e.g., the bottom surface 13 of FIG. 2) of the washing chamber C may be formed to be inclined toward the sump assembly 100. The washing water may be collected in the sump assembly 100 along the bottom surface 13.

[0072] According to an embodiment, the sump assembly 100 may include a sump housing 150 and a plurality of filters 101 for collecting foreign objects included in washing water.

[0073] According to an embodiment, the plurality of filters 101 may be provided corresponding to the particle sizes of the foreign objects. For example, the plurality of filters 101 may include a coarse filter 110, a fine filter 120, and a micro filter 130. For example, the core filter 110 may form relatively large through holes compared to the other filters (e.g., the fine filter 120 and/or the micro filter 130), the fine filter 120 may form relatively medium through holes compared to the other filters, and the micro filter 130 may form relatively small through holes compared to the other filters.

[0074] According to an embodiment, the micro filter 130 is formed in a cylindrical shape with open upper and lower surfaces, and may collect foreign objects having small sizes.

[0075] According to an embodiment, the coarse filter 110 is disposed through the upper surface of the open micro filter 130, and may collect foreign objects having particles of a predetermined size or larger before reaching the micro filter 1230.

[0076] According to an embodiment, the fine filter 120 may be formed to have through holes larger than the micro filter 130 and smaller than the coarse filter 110, and may be disposed to cover an upper portion of the sump housing 150. The coarse filter 110 may be formed in a lattice shape to collect foreign objects of a predetermined size or more. The fine filter 120 may be detachably disposed on the open upper surface of the micro filter 130.

[0077] According to an embodiment, the sump housing 150 may have a hemispherical shape in which an upper surface is substantially open. The sump housing 150 may include a first sump housing 152 positioned at an upper portion, a third sump housing 154 positioned at a lower portion, and a second sump housing 153 positioned between the first sump housing 152 and the third sump housing 154.

[0078] According to an embodiment, foreign objects removed from the dishes in the process of washing the dishes may be collected by the plurality of filters 101. The plurality of filters 101 may collect foreign objects corresponding to the particle sizes of the foreign objects. When foreign objects above a threshold level are collected in the plurality of filters 101, it may be impossible to smoothly pump the washing water collected in the sump assembly 100 by the circulation pump 30. This may deteriorate the washing performance of the dishwasher 1. Hereinafter, the dishwasher 1 according to the disclosure may transmit information about the filter clogging state to the user or to instruct the user to clean the filter when foreign objects are collected in the plurality of filters 101 at a certain level or higher, and there is a concern that filter performance will deteriorate.

[0079] According to an embodiment, the dishwasher 1 may obtain information about the input current of the running circulation pump 30 and the amount of washing water stored in the tub (e.g., the tub 12 of FIG. 2), and determine whether the filter is clogged based on the information about the input current and the amount of washing water.

[0080] According to an embodiment, the dishwasher 1 may obtain information about the input current of the running circulation pump 30, and compare it with the current (hereinafter, referred to as a reference current of the circulation pump 30) for driving the circulation pump 30 when it is normally driven to determine whether the circulation pump 30 is normally driven.

[0081] According to an embodiment, the dishwasher 1 may sense vibration generated in the tub 12 as the circulation pump 30 is driven, and obtain vibration characteristics based on a frequency response function. The dishwasher 1 may determine the amount of washing water stored in the tub 11 from the vibration characteristics of the tub 11. To that end, the dishwasher 1 may include a vibration sensor (e.g., the vibration sensor 340 of FIG. 5). The vibration sensor 340 may be disposed around the sump assembly 100 to sense vibration generated in the tub 12 according to the driving of the circulation pump 100. The vibration sensor 340 may be installed at a position advantageous for detecting vibration characteristics in the tub 12. This is described with reference to FIGS. 5 and 6.

[0082] According to an embodiment, the dishwasher 1 may determine whether the filter is clogged based on information about the input current of the circulation pump 30 and information about the amount of washing water stored in the tub 11. When the dishwasher 1 determines that the filter is in the clogged state, the dishwasher 1 may transmit information indicating the clogged state of the filter to an external device (e.g., a user terminal or a hub device) and/or information instructing to clean the filter. Hereinafter, a block diagram and a control flowchart for determining the filter clogging state by the dishwasher 1 are described below with reference to FIG. 7.

[0083] FIG. 5 is a bottom view illustrating a sump assembly (e.g., the sump assembly 100 of FIG. 2) as viewed upward according to an embodiment of the disclosure. FIG. 5 may be understood as a bottom view of the sump assembly 100 viewed from the lower side of the machine room (e.g., the machine room L of FIG. 2) toward the sump assembly 100.

[0084] The embodiment of FIG. 5 may be selectively combined with the embodiments of FIGS. 1 to 4B.

[0085] Referring to FIG. 5, the sump assembly 100 may include a sump housing 150 forming the exterior. The sump housing 150 may include a first sump housing (e.g., the first sump housing 152 of FIG. 4A) positioned at an upper portion, a third sump housing (e.g., the third sump housing 154 of FIG. 4A) positioned at a lower portion, and a second sump housing (e.g., the second sump housing 153 of FIG. 4A) positioned between the first sump housing 152 and the third sump housing 154.

[0086] According to an embodiment, the sump assembly 100 may include a circulation chamber 151 formed by a portion of the sump housing 150 and a micro filter (e.g., the micro filter 130 of FIG. 4A). The circulation chamber 151 may be formed by an inner circumferential surface of the second sump housing 153 and a portion of the third sump housing 154.

[0087] According to an embodiment, the circulation chamber 151 may form a space for collecting at least a portion of washing water flowing into the sump assembly 100 through a plurality of filters (e.g., the plurality of filters 101 of FIG. 4B). The circulation chamber 151 may communicate with each of a drain pump (e.g., the drain pump 40 of FIG. 2) and a circulation pump (e.g., the circulation pump 30 of FIG. 2). Some of the washing water collected into the circulation chamber 151 may be drained to the outside of the dishwasher 1 along a drain hose (e.g., the drain hose 20 of FIG. 3) by the drain pump 40, or may be jetted from the first to third jet nozzles 41, 42, and 43 by the circulation pump 30.

[0088] According to an embodiment, the dishwasher 1 may determine the degree of clogging of the filter 101 based on information about the driving current of the circulation pump 30 and information about the vibration characteristics in the tub 12. For example, in order to obtain the information about the driving current of the circulation pump 30, the dishwasher 1 may include a current sensor (e.g., the current sensor 350 of FIG. 7). For example, in order to obtain the information about the vibration characteristics in the tub 12, the dishwasher 1 may include a vibration sensor (e.g., the vibration sensor 340 of FIG. 7).

[0089] According to an embodiment, the vibration sensor 340 may be configured to sense vibration characteristics of a vibrating object by converting a physical vibration caused by vibration of the tub 12 and washing water stored in the tub 12 by the driving of the circulation pump 30 into an electrical signal indicating a sensed value. The vibration sensor 340 may be implemented as, e.g., an acceleration sensor or an accelerometer. For example, depending on the measurement type, the vibration sensor 340 may be implemented as a piezoelectric type accelerometer or a strain gauge type accelerometer, and may be implemented as a piezoresistive type accelerometer or a capacitive type accelerometer.

[0090] According to an embodiment, the vibration sensor 340 may sense different vibration characteristics corresponding to the amount of washing water collected in the tub 12 and produce a sensed value. For example, the vibration sensor 340 may sense different vibration characteristics corresponding to the amount of washing water collected in the tub 12, and based thereupon, the dishwasher 1 may derive different natural frequency values based on the vibration characteristics. The dishwasher 1 may predict the amount of washing water collected in the tub 12 based on the derived natural frequency value. The dishwasher 1 may derive a frequency response function based on the sensed value produced by the vibration sensor 340, and derive the natural frequency of the tub 12 according to the washing water collected in a predetermined amount using the frequency response function.

[0091] According to an embodiment, the vibration sensor 340 may be disposed at an advantageous position for sensing the vibration characteristics of the tub 12. For example, corresponding to the position of the vibration sensor 340, the peak value of the natural frequency may vary, and/or the degree of being affected by the noise signal around the natural frequency may vary. Accordingly, the vibration sensor 340 may be disposed at a point where the amplification degree of the output signal relative to the input signal according to the driving of the circulation pump 30 is large.

[0092] According to an embodiment, the vibration sensor 340 may be positioned near the sump assembly 100. For example, the vibration sensor 340 may be disposed (e.g., installed) under the sump housing 150. For example, the vibration sensor 340 may be disposed near the circulation pump 30. For example, the vibration sensor 340 may be disposed under the sump housing 150 near the circulation pump 30. However, the disclosure is not limited thereto, and the position of the vibration sensor 340 may be determined considering factors advantageous for sensing vibration characteristics.

[0093] Referring to FIG. 5, the vibration sensor 340 may be disposed in any one of the first to eighth areas 170a, 170b, 170c, 170d, 170e, 170f, 170g, and 170h. For example, the vibration sensor 340 may be disposed at a position for sensitively sensing vibration characteristics among the first to eighth areas 170a, 170b, 170c, 170d, 170e, 170f, 170g, and 170h. A condition for selecting the position of the vibration sensor 340 is described in connection with FIG. 6.

[0094] According to an embodiment, the vibration sensor 340 may be disposed in the third area 170c or the fourth area 170d. When the vibration sensor 340 is disposed in the third area 170c or the fourth area 170d, the vibration sensor 340 may sensitively sense vibration characteristics in the tub 12 caused by the driving of the circulation pump 30 and produce a corresponding sensed value.

[0095] FIG. 6 is a graph for selecting an optimal position of a vibration sensor (e.g., the vibration sensor 340 of FIG. 7) installed in a sump assembly 100 according to an embodiment of the disclosure.

[0096] Referring to FIG. 6, the horizontal axis of the illustrated graph represents the input signal according to the degree of vibration generated by the driving of the circulation pump (e.g., the circulation pump 30 of FIG. 2), and the vertical axis of the illustrated graph represents the sensed value produced by the vibration sensor 340 in response to the input signal.

[0097] According to an embodiment, the sensed value of the vertical axis produced by the vibration sensor 340 may derive different result values according to the positions of the vibration sensor 340. For example, the vibration sensed by the vibration sensor 340 may be amplified differently corresponding to the position even though it is the same input signal. Further, a different noise signal may be input to the vibration sensed by the vibration sensor 340 by the presence or absence or shape of a structure positioned around, corresponding to the position of the vibration sensor 340 although it is the same input signal. Therefore, in order to increase the sensitivity and accuracy of the sensed value produced by the vibration sensor 340, the vibration sensor 340 may be required to be disposed at an optimal position among the first to eighth areas 170a, 170b, 170c, 170d, 170e, 170f, 170g, and 170h shown in FIG. 5.

[0098] According to an embodiment, the three graphs illustrated in FIG. 6 illustrate sensed values produced by the vibration sensor 340 disposed at different positions among the first to eighth areas 170a, 170b, 170c, 170d, 170e, 170f, 170g, and 170h. Here, it may be understood that as the peak value of the vertical axis increases, the vibration sensed by the vibration sensor 340 according to the input signal is amplified larger and sensed.

[0099] According to an embodiment, the graph indicated by thick solid line among the three graphs illustrates the sensed value produced by the vibration sensor 340 when the vibration sensor 340 is disposed at the first position. The first position may correspond to any one of the third area 170c or the fourth area 170d of FIG. 5. For example, the graph indicated by the thick solid line may be understood as illustrating the sensed value when the vibration sensor 340 is disposed at a point adjacent to the circulation pump 30.

[0100] According to an embodiment, the graph indicated by thin solid line among the three graphs illustrates the sensed value produced by the vibration sensor 340 when the vibration sensor 340 is disposed at the second position.

[0101] According to an embodiment, the graph indicated by dashed line among the three graphs illustrates the sensed value produced by the vibration sensor 240 when the vibration sensor 340 is disposed at the third position.

[0102] According to an embodiment, when the vibration sensor 340 is disposed at a point adjacent to the circulation pump 30, a vibration generated according to the driving of the circulation pump 30 may be more sensitively sensed. However, the position of the vibration sensor 340 is not limited to any one of the first to eighth areas 170a, 170b, 170c, 170d, 170e, 170f, 170g, and 170h of FIG. 5, and may be disposed at any point under the sump assembly 100 according to the position of the circulation pump 30 and the driving specifications of the circulation pump 30. Further, when the vibration sensor 340 senses a vibration generated by a separate excitation means (e.g., the actuator 370 of FIG. 7) rather than the vibration generated by the circulation pump 30, the position of the vibration sensor 340 may be determined considering the position where the vibration generated by the actuator 370 is sensitively receivable.

[0103] FIG. 7 is a block diagram illustrating a dishwasher (e.g., the dishwasher 1 of FIG. 1) according to an embodiment of the disclosure.

[0104] The embodiment of FIG. 7 may be selectively combined with the embodiment of FIGS. 1 to 6.

[0105] Referring to FIG. 7, the dishwasher 1 may include a controller 310, an input unit 210, an output unit 220, a communication unit (transceiver) 330, a vibration sensor 340, a current sensor 350, a circulation pump 30, a drain pump 40, and a valve 360.

[0106] According to an embodiment, the input unit 210 may receive a user input. The input unit 210 may receive the user input by a physical press or touch. The input unit 210 may receive course information for the dishwasher 1 to perform washing or the user input for a time for performing washing. The input unit 210 may receive a user input for opening the door (e.g., the door 11 of FIG. 1) of the dishwasher 1.

[0107] According to an embodiment, the output unit 220 may output operation information and/or state information about the dishwasher 1. The output unit 220 may be implemented as a display for visually outputting the operation information and/or the state information about the dishwasher 1, or may be implemented as a speaker for audibly outputting the operation information and/or the state information about the dishwasher 1.

[0108] According to an embodiment, the input unit 210 and the output unit 220 may be implemented independently or integrally. When the input unit 210 and the output unit 220 are implemented in the form of an input/output unit 200, the input/output unit 200 may be implemented as a touchscreen panel.

[0109] According to an embodiment, the communication unit 330 may exchange data with external devices, such as a server device (e.g., the server 3 of FIG. 14), and/or a user terminal (e.g., the user terminal of FIG. 14). The communication unit 330 may include a wired communication module for wiredly exchanging data with external devices and a wireless communication module for wirelessly exchanging data with external devices.

[0110] According to an embodiment, the wired communication module may access a wired communication network and communicate with external devices through the wired communication network. For example, the wired communication module may access the wired communication network through Ethernet (Ethernet, IEEE 802.3 technology standard) and receive data from the external devices through the wired communication network.

[0111] According to an embodiment, the wireless communication module may wirelessly communicate with a base station or an access point (AP), and may access the wired communication network through the base station or the access point. The wireless communication module may also communicate with the external devices connected to the wired communication network via the base station or the access point. For example, the wireless communication module 1843 may wirelessly communicate with the access point (AP) using Wi-Fi (IEEE 802.11 technology standard), or communicate with the base station using CDMA, WCDMA, GSM, long term evolution (LET), or Wi-Bro. The wireless communication module may also receive data from the external devices via the base station or the access point. Further, the wireless communication module may directly communicate with the external devices. For example, the wireless communication module may receive data wirelessly from the external devices using Wi-Fi, Bluetooth (IEEE 802.15.1 technology standard), ZigBee (IEEE 802.15.4 technology standard), etc.

[0112] According to an embodiment, the communication unit 330 may transmit or receive data with the external devices, and may transfer data received from the external devices to the controller 310.

[0113] According to an embodiment, the vibration sensor 340 may sense the vibration characteristics of the tub (e.g., the tub 11 of FIG. 2), and produce a corresponding sensed value. The vibration sensor 340 may sense the vibration characteristics of the tub 11 that vibrates according to the driving of the circulation pump 30 (e.g., the circulation pump 30 of FIG. 2), and produce a corresponding sensed value. The vibration sensor 340 may sense different vibration characteristics in response to the amount of washing water collected in the tub 11, and produce a corresponding sensed value.

[0114] According to an embodiment, the vibration sensor 340 may be implemented as an accelerometer. The vibration sensor 340 may be implemented as a piezoelectric type accelerometer or a strain gauge type accelerometer depending on the measurement type. Further, it may be implemented as a piezoresistive type accelerometer or a capacitive type accelerometer.

[0115] According to an embodiment, in addition to sensing the vibration characteristics of the tub 11 by the driving of the circulation pump 30, the vibration sensor 340 may also sense vibration characteristics of the tub 11 by the driving of a separate excitation member (e.g., the actuator 370) and produce a corresponding sensed value. To that end, the dishwasher 1 may further include an actuator 370. The actuator 370 may be configured to generate a predetermined vibration according to a predetermined driving period.

[0116] According to an embodiment, the current sensor 350 may sense an input current input to the circulation pump 30, and produce a corresponding sensed value. The current sensor 350 may sense an input current input to the running circulation pump 30 and indicate the sensed input current, or provide the sensed value indicating the input current, to the controller 310. The controller 310 may obtain the input current from the current sensor 350, or from the sensed value produced by the current sensor 350, and compare a reference current when the circulation pump 30 is normally operated with the input current to determine whether the circulation pump 30 is normally operated. For example, when the input current of the circulation pump 30 as indicated by the sensed value produced by the current sensor 350 is lower than a threshold level for the reference current, the circulation pump 30 may be determined to currently have an output decreased as compared with the normal driving. When the output of the circulation pump 30 is decreased, it may be determined that the amount of washing water present in the tub 12 has been decreased.

[0117] According to an embodiment, the controller 310 may be configured to process communication data received from an external device and/or a user input and control the components included in the dishwasher 1 based on the data processing. For example, the controller 310 may control the circulation pump 30 and/or the drain pump 40 to be turned on/off by transmitting a control signal for driving the circulation pump 30 and/or the drain pump 40. For example, the controller 310 may transmit a control signal for opening or closing a plurality of valves 40 in response to a washing cycle, thereby forming a flow path where the washing water flows.

[0118] According to an embodiment, the controller 310 includes a memory 313 that stores/records programs and/or data, and a processor 311 that processes user input and/or communication data according to the program and/or data stored in the memory 313.

[0119] According to an embodiment, the memory 313 may store/memory a program and/or data. The program includes a plurality of instructions combined to perform a specific function, and the data may be processed and/or treated by a plurality of instructions included in the program. Further, the program and/or data may include system programs and/or system data directly related to the operation of the dishwasher 1, and application programs and/or application data that provide convenience to the user.

[0120] According to an embodiment, the memory 313 may include a non-volatile memory storing a program and/or data for controlling the components included in the dishwasher 1 and a volatile memory storing temporary data generated during controlling the components included in the dishwasher 1.

[0121] According to an embodiment, the non-volatile memory may store programs and/or data, e.g., electrically, magnetically or optically. The non-volatile memory may include, e.g., a read only memory or flash memory for storing data for a long time. The non-volatile memory may also include a solid state drive (SSD), a hard disk drive (HDD), or an optical disc drive (ODD).

[0122] According to an embodiment, the volatile memory may load the program and/or data from the non-volatile memory, e.g., and may electrically store the program and/or data. The volatile memory may include, e.g., static random access memory (S-RAM) and dynamic random access memory (D-RAM) for temporarily storing data.

[0123] The memory 313 may store/record programs and data such as operating systems (OS), middleware, and applications, and may provide the programs and data to the processor 311 in response to a request of the processor 311.

[0124] According to an embodiment, the processor 311 may process a user input of the input unit 210 and sensed values produced the vibration sensor 340 and the current sensor 350, and/or communication data of the communication unit 330 according to the program and/or data stored/recorded in the memory 313. The processor 311 may generate a control signal for controlling the sensor operation of the sensor, the driving of the circulation pump 30 and the drain pump 40, and the operation of the communication unit 330 based on data processing.

[0125] According to an embodiment, the processor 311 may determine whether the filter is clogged by processing sensed values produced the vibration sensor 340 and the current sensor 350. For example, the processor 311 may determine whether the circulation pump 30 is being driven with a normal driving output based on a sensed value produced by the current sensor 350. For example, the processor 311 may determine the amount of washing water present in the tub 12 based on a sensed value produced by the vibration sensor 340. When the driving output of the circulation pump 30 is less than a threshold level based on the sensed value, the processor 311 may determine whether it is due to insufficient amount of washing water or clogging of the filter. In this regard, control steps related to a detection method for the dishwasher 1 to detect filter clogging are described in FIGS. 9 and 10.

[0126] FIG. 8 schematically illustrates a process in which a dishwasher (e.g., the dishwasher 1 of FIG. 1) calculates a natural frequency corresponding to a vibration generated in a tub (e.g., the tub 12 of FIG. 2) according to an embodiment of the disclosure.

[0127] The embodiment of FIG. 8 may be selectively combined with the embodiment of FIGS. 1 to 7.

[0128] Referring to FIG. 8, a circulation pump (e.g., the circulation pump 30 of FIG. 2) may be driven in response to initiation of the washing process of the dishwasher 1. If the circulation pump 30 is driven, washing water may be collected into the tub 12, vibration may occur according to the driving of the circulation pump 30, and an input signal 410 according to the vibration may be generated. The input signal 410 may include, e.g., not only vibration according to the driving of the circulation pump 30, but also noise signals corresponding to the type and shape of a structure disposed inside the dishwasher 1. For example, the noise signal may be detected as a tone-to-noise ratio (TTNR) in the frequency band around the natural frequency according to the vibration of the washing water in the tub 12.

[0129] According to an embodiment, the vibration sensor 340 (e.g., the vibration sensor 340 of FIG. 7) may sense the output signal 430 according to the input signal 410 generated according to the driving of the circulation pump 30, and produce a corresponding sensed value. The vibration sensor 340 may sense the output signal 430 based on the noise signal and the vibration according to the driving of the circulation pump 30 included in the input signal 410.

[0130] According to an embodiment, the vibration sensor 340 may sense different output signals 430 corresponding to positions. The vibration sensor 340 may select an optimal position considering, e.g., a peak value of the output signal 430 corresponding to the input signal 410 and the noise signal included in the input signal 410.

[0131] According to an embodiment, the dishwasher 1 may calculate the natural frequency of the tub 12 based on the input signal 410 and the output signal 430. For example, the dishwasher 1 may calculate the natural frequency of the tub 12 using a system function (e.g., a frequency response function) 420 based on the input signal 410 and the output signal 430.

[0132] According to an embodiment, the system function 420 may be set based on a motion equation and a fluid motion equation according to the tub 12 and the fluid (e.g., washing water) stored in the tub 12. In other words, the system function 420 may be understood as a structure-fluid coupled system. Equation 1 below shows the motion equation of the structure, and Equation 2 below shows the motion equation of the fluid.

[00001]$\begin{array}{cc}\left[M_S\right]\stackrel{.Math.}{u}+\left[C_S\right]\stackrel{.}{u}\left[K_S\right]u=f_O+f_F& \left[\mathrm{Equation}1\right]\end{array}$$\begin{array}{cc}{}_F\frac{V}{t}=-P& \left[\mathrm{Equation}2\right]\end{array}$

[0133] According to an embodiment, in the structure formed by the tub 12 and the washing water stored in the tub 12, the behavior of the fluid at the contact surface between the structure and the fluid may apply any external force to the structure. Therefore, the motion equation considering Equation 1 and Equation 2 may be derived as Equation 3 below.

[00002]$\begin{array}{cc}\left\{K-{}^2\left(M+M^{*}\right)\right\}U=0& \left[\mathrm{Equation}3\right]\end{array}$

[0134] According to an embodiment, the natural frequency of the washing water collected in the tub 12 from Equation 3 may be derived from Equation 4 below.

[00003]$\begin{array}{cc}{\left({\mathrm{Freq}}_{\mathrm{water}}\right)}_i=\frac{1}{2}\sqrt{\frac{k_i}{m_i+m_i^{*}}}=\frac{1}{\sqrt{1+{}_i}}{\left({\mathrm{Freq}}_{\mathrm{air}}\right)}_i& \left[\mathrm{Equation}4\right]\end{array}$

[0135] According to an embodiment, (Freq.sub.water).sub.i may be defined as an i.sup.th natural frequency of washing water stored in the tub 12, and m.sub.i* may be defined as an i.sup.th mass of washing water. Through Equation 4, it may be derived that the natural frequency of the washing water may be determined by the amount (mass) of the washing water stored in the tub 12.

[0136] According to an embodiment, the dishwasher 1 may determine whether the amount of washing water is less than a threshold level based on the natural frequency of washing water sensed through the vibration sensor 340. The dishwasher 1 may determine whether a filter (e.g., the plurality of filters 101 of FIG. 4B) is clogged based on the amount of washing water and the intensity of the input signal of the circulation pump 30 being driven.

[0137] FIG. 9 is a control flowchart for a dishwasher (e.g., the dishwasher 1 of FIG. 1) to determine a clogged state of a filter (e.g., the plurality of filters 101 of FIG. 4B) according to an embodiment of the disclosure.

[0138] FIG. 10 is a control flowchart for a dishwasher 1 to determine a clogged state of a filter 101 according to an embodiment of the disclosure.

[0139] The embodiments of FIGS. 9 and 10 may be selectively combined with the embodiments of FIGS. 1 to 8.

[0140] Some of the operations shown in the flowcharts of FIGS. 9 and 10 may be omitted or repeatedly performed or, as necessary, may be performed in a different order.

[0141] Referring to FIG. 9, in operation 910, the dishwasher 1 may obtain a driving current of a circulation pump (e.g., the circulation pump 30 of FIG. 2). The dishwasher 1 may determine whether the circulation pump 30 is being driven normally by obtaining the driving current of the circulation pump 30. For example, when the driving current of the circulation pump 30 is lower than a threshold level, the dishwasher 1 may determine that the circulation pump 30 is not normally pumping smoothly the washing water collected in the tub (e.g., the tub 12 of FIG. 2). When the circulation pump 30 is abnormally driven, the dishwasher 1 may collect information about vibration characteristics in the tub 12, and determine whether the filter 101 is clogged based on information about the driving current of the circulation pump 30 and information about vibration characteristics in the tub 12.

[0142] According to an embodiment, the dishwasher 1 may obtain vibration characteristics in the tub 12 in operation 920. The dishwasher 1 may obtain vibration characteristics in the tub 12 from a vibration sensor (e.g., the vibration sensor 340 of FIG. 7).

[0143] According to an embodiment, the dishwasher 1 may obtain information about the natural frequency of the tub 12 and the washing water stored in the tub 12 due to vibration generated according to the driving of the circulation pump 30.

[0144] According to an embodiment, the dishwasher 1 may obtain the natural frequency of the tub 12 at a plurality of times in order to obtain the vibration characteristics in the tub 12.

[0145] According to an embodiment, the dishwasher 1 may obtain the natural frequency of the tub 12 at a specific time as the washing cycle of the water supply process-washing process-rinsing process-drying process proceeds. For example, the dishwasher 1 may obtain the natural frequency of the tub 12 in response to the initiation of the water supply process. The natural frequency of the tub 12 at the time may be defined as a first natural frequency. For example, the dishwasher 1 may obtain the natural frequency of the tub 12 when the washing process is initiated and the driving current input to the circulation pump 30 is less than a threshold level. The natural frequency of the tub 12 at this time may be defined as a second natural frequency.

[0146] According to an embodiment, the dishwasher 1 may determine whether the amount (or water level) of washing water collected in the tub 12 is sufficient based on the first natural frequency and the second natural frequency. For example, if the difference between the first natural frequency and the second natural frequency is more than the threshold level, the dishwasher 1 may determine that the amount of washing water replenished after the water supply process is finished is sufficient compared to the amount of washing water at the start of the water supply process. For example, if the difference between the first natural frequency and the second natural frequency is less than the threshold level, the dishwasher 1 may determine that the amount of washing water replenished after the water supply process is finished is insufficient compared to the amount of washing water at the start of the water supply process.

[0147] According to an embodiment, in operation 930, the dishwasher 1 may determine whether the filter 101 is clogged. The dishwasher 1 may determine whether the filter 101 is clogged based on the information about the driving current of the circulation pump 30 and the information about the vibration characteristics of the tub 12 obtained in operations 910 and 920, respectively.

[0148] According to an embodiment, if the driving current of the circulation pump 30 is less than the threshold level, and the difference between the first natural frequency and the second natural frequency exceeds the threshold level, the dishwasher 1 may determine that the circulation pump 30 operates abnormally due to the clogging of the filter 101 by foreign objects even though the amount of washing water collected in the tub 12 is sufficient.

[0149] According to an embodiment, if the driving current of the circulation pump 30 is less than the threshold level, and the difference between the first natural frequency and the second natural frequency is less than the threshold level, the dishwasher 1 may determine that the circulation pump 30 operates abnormally due to an insufficient amount of washing water collected in the tub 12.

[0150] According to an embodiment, in operation 940, the dishwasher 1 may output information instructing to clean the filter 101. The dishwasher 1 may output guide information for guiding the user to clean the filter 101 due to the clogging of the filter 101. For example, the dishwasher 1 may visually display the guide information through a display included in the output unit 220, or may audibly output the guide information through a speaker included in the output unit 220. The operation of the dishwasher 1 visually displaying the guide information through the display is described below in detail in connection with FIG. 16.

[0151] According to an embodiment, the dishwasher 1 may transfer information indicating that the filter 101 is clogged and guide information guiding the user to clean the filter 101 due to the clogging of the filter 101 to the external device. The dishwasher 1 may transfer the guide information to an external device (e.g., the user terminal 2 of FIG. 14 or other home appliances 1401 to 1409 installed in the house) through a hub device (e.g., the hub device 1400 of FIG. 14), or wirelessly transfer the guide information directly to the external device. The hub device 1400 or the external device receiving the guide information may output the guide information through a display or speaker provided for each device. The operation of transmitting information indicating that the filter 101 of the dishwasher 1 is clogged and/or guide information, which is information instructing to clean the filter 101, to the external device and outputting the guide information by the external device is described below in detail in connection with FIG. 14.

[0152] Referring to FIG. 10, the dishwasher 1 may obtain the first natural frequency in operation 1010. The first natural frequency may be defined as a natural frequency calculated from the vibration characteristics of the tub 12 obtained by the dishwasher 1 from sensed values produced by the vibration sensor 340 in response to the initiation of the water supply process included in the washing cycle. The dishwasher 1 may determine the amount (or water level) of washing water collected in the tub 12 based on the first natural frequency obtained in operation 1010 and the second natural frequency obtained in operation 1010 to be described below.

[0153] According to an embodiment, the dishwasher 1 may obtain the driving current of the circulation pump 30 in operation 1020. The dishwasher 1 may detect the driving current input to the circulation pump 30 from a sensed value produced by the current sensor (e.g., the current sensor 350 of FIG. 7). For example, the dishwasher 1 may obtain the driving current of the circulation pump 30 in real-time from a sensed value produced by the current sensor 350, or obtain the driving current every preset time period.

[0154] According to an embodiment, in operation 1030, the dishwasher 1 may determine whether the driving current of the circulation pump 30 is less than the threshold current I_th. The threshold current I_th may be defined as a current input to the circulation pump 30 when the filter performance is reduced below a certain level due to foreign objects collected in the filter 101 (e.g., when the filter performance is reduced to 30% of that of an unused filter). According to an embodiment, in response to the dishwasher 1 determining that the driving current of the circulation pump 30 is lower than the threshold current I_th, the dishwasher 1 may obtain the second natural frequency in operation 1040. For example, the dishwasher 1 may obtain the second natural frequency from the vibration characteristics of the tub sensed by the vibration sensor 340 when the driving current after the water supply process is finished is lower than the threshold current I_th.

[0155] According to an embodiment, in operation 1050, the dishwasher 1 may determine whether variation in the natural frequency exceeds a preset threshold range. The dishwasher 1 may determine whether a difference value between the first natural frequency obtained in operation 1010 and the second natural frequency obtained in operation 1040 exceeds the preset threshold range.

[0156] According to an embodiment, when the variation (or difference) in the first natural frequency and the second natural frequency exceeds the threshold range, the dishwasher 1 may determine that the washing water has been sufficiently collected in the tub 12 between the time when the water supply process starts and the time when the water supply process ends. For example, if the variation (or difference) in the first natural frequency and the second natural frequency is within the threshold range, the dishwasher 1 may determine that the washing water has not been sufficiently collected in the tub 12 between the time when the water supply process starts and the time when the water supply process ends, and in operation 1081, may determine that the amount of washing water collected in the tub 12 is insufficient.

[0157] According to an embodiment, in operation 1083, the dishwasher 1 may determine whether the number of times the washing water is replenished exceeds a threshold number. For example, if the number of times of replenishing washing water does not exceed the preset threshold number, the dishwasher 1 may open the water supply valve to replenish the washing water by a predetermined amount into the tub 12 in operation 1085.

[0158] According to an embodiment, if the variation (or difference) in the first natural and the second natural frequency exceeds the threshold range, the dishwasher 1 may determine that the filter 101 is in a clogged state in operation 1060. If the variation (or difference) in the first natural frequency and the second natural frequency exceeds the threshold range and the driving current of the circulation pump 30 is lower than the threshold current, the dishwasher 1 may determine that the circulation pump 30 is abnormally driven due to the clogging of the filter 101 although the amount of washing water collected in the tub 12 is sufficient.

[0159] According to an embodiment, in operation 1070, the dishwasher 1 may transfer guide information including information indicating that the filter 101 is clogged and/or information instructing the user to clean the filter 101 to the output unit (e.g., the output unit 220 of FIG. 7) or an external device (e.g., the hub device 1400 or the user terminal 2 of FIG. 14).

[0160] According to an embodiment, the dishwasher 1 may display the guide information on the display or output the guide information through the speaker. A specific operation embodiment in which the dishwasher 1 displays the guide information on the display is described with reference to FIG. 16.

[0161] According to an embodiment, a specific operation embodiment in which the dishwasher 1 transfers the guide information to an external device and the external device outputs the guide information is described below in detail with reference to FIG. 14.

[0162] FIG. 11 is a graph illustrating a driving current input to a circulation pump (e.g., the circulation pump 30 of FIG. 2) according to filter performance according to an embodiment of the disclosure for each driving rpm of the circulation pump 30.

[0163] The embodiment of FIG. 11 may be selectively combined with the embodiment of FIGS. 1 to 10.

[0164] Referring to FIG. 11, the horizontal axis of the graph indicates the performance of a filter (e.g., the filter 101 of FIG. 4B). The filter performance may be defined as the degree of clogging of the filter 101 by foreign objects collected by the filter 101 as the dishwasher 1 repeatedly performs the washing cycle. For example, it may be assumed that the filter performance of an unused filter 101 is 100%, and the filter performance when the fluid (e.g., washing water) no longer passes through the filter 101 due to foreign objects collected in the filter 101 is 0%. p1, p2, p3, p4, p5, and p6 indicate 0%, 20%, 40%, 60%, 80%, and 90%, respectively.

[0165] According to an embodiment, the vertical axis of the graph indicates the input current of the circulation pump 30 being driven according to the filter performance.

[0166] According to an embodiment, when the washing cycle proceeds, the circulation pump 30 may pump the washing water stored in the sump assembly (e.g., the sump assembly 100 of FIG. 2) at various speeds. FIG. 11 may be understood as illustrating, in four curve graphs, the input currents of the circulation pump 30 according to the filter performance for each rpm at which the circulation pump 30 is driven.

[0167] According to an embodiment, the curved graph denoted by circles (.circle-solid.) represents the input current according to the filter performance when the circulation pump 30 is driven at a speed of a first rpm. The first rpm may be, e.g., 2800 rpm to 3200 rpm.

[0168] According to an embodiment, the curved graph denoted by triangles (.box-tangle-solidup.) represents the input current according to the filter performance when the circulation pump 30 is driven at a speed of a second rpm. The second rpm may be, e.g., 3200 rpm to 3600 rpm.

[0169] According to an embodiment, the curved graph denoted by rhombuses (.diamond-solid.) represents the input current according to the filter performance when the circulation pump 30 is driven at a speed of a third rpm. The first rpm may be, e.g., 3600 rpm to 4000 rpm.

[0170] According to an embodiment, the curved graph denoted by rectangles (.square-solid.) represents the input current according to the filter performance when the circulation pump 30 is driven at a speed of a fourth rpm. The fourth rpm may be, e.g., 4000 rpm to 4400 rpm.

[0171] Referring to the four graphs shown, it may be understood that the current value of the driving current input to the circulation pump 30 decreases as the filter performance decreases. For example, when the filter performance is p6 (e.g., 90%), the intensity of the driving current of the circulating pump 30 may be reduced by about 11% to 15% as compared with when the filter performance is p2 (e.g., 30%).

[0172] According to an embodiment, the dishwasher 1 may obtain a driving current input to the circulation pump 30 from a sensed value produced by a current sensor (e.g., the current sensor 350 of FIG. 7), and determine whether the circulation pump 30 is operating normally based on the driving current (e.g., operation 910 of FIG. 9 and/or operation 1020 of FIG. 10). The dishwasher 1 may determine whether the filter 101 is clogged based on information about whether the circulation pump 30 operates normally and the vibration characteristics of the tub (e.g., the tub 12 of FIG. 2).

[0173] FIG. 12 is a graph illustrating a natural frequency of a tub (e.g., the tub 12 of FIG. 2) for each driving rpm of a circulation pump (e.g., the circulation pump 30 of FIG. 2) according to the volume of washing water stored in the tub 12 according to an embodiment of the disclosure.

[0174] The embodiment of FIG. 12 may be selectively combined with the embodiments of FIGS. 1 to 11.

[0175] Referring to FIG. 12, the horizontal axis of the graph indicates the volume of washing water stored in the tub 12. For example, V1 may correspond to 0 L (e.g., no washing water in the tub 12), V2 may correspond to 1 L, V3 may correspond to 2 L, V4 may correspond to 3 L, and V5 may correspond to 4 L. The vertical axis of the graph indicates the natural frequency according to the vibration characteristics of the tub 12 corresponding to the volume of washing water stored in the tub 12.

[0176] According to an embodiment, the dishwasher (e.g., the dishwasher 1 of FIG. 1) may obtain information about the vibration characteristics of the tub 12 from sensed values produced by the vibration sensor (e.g., the vibration sensor 340 of FIG. 7). The dishwasher 1 may obtain the vibration characteristics of the tub 12 and the washing water stored in the tub 12 according to the vibration generated by the driving of the circulation pump 30, and calculate the natural frequency of the tub 12 based on the vibration characteristics.

[0177] According to an embodiment, when the washing cycle proceeds, the circulation pump 30 may pump the washing water stored in the sump assembly (e.g., the sump assembly 100 of FIG. 2) at various speeds. In FIG. 12, it may be understood that the natural frequency of the tub 12 according to the volume of washing water for each rpm at which the circulation pump 30 is driven is shown as three curve graphs.

[0178] According to an embodiment, the curved graph denoted by triangles (.box-tangle-solidup.) represents the input current according to the filter performance when the circulation pump 30 is driven at a speed of a first rpm. The first rpm may be, e.g., 2200 rpm to 2600 rpm.

[0179] According to an embodiment, the curved graph denoted by rectangles (.square-solid.) represents the input current according to the filter performance when the circulation pump 30 is driven at a speed of a fourth rpm. The fourth rpm may be, e.g., 3400 rpm to 3800 rpm.

[0180] According to an embodiment, the curved graph denoted by circles (.circle-solid.) represents the input current according to the filter performance when the circulation pump 30 is driven at a speed of a first rpm. The first rpm may be, e.g., 5200 rpm to 5600 rpm.

[0181] Referring to the three graphs shown, it may be understood that the natural frequency of the tub 12 is decreased as the water level of the washing water increases. For example, if as much washing water as V1 (e.g., OL) is stored in the tub 12, the natural frequency may be reduced by 83% to 93% compared to when as much washing water as V4 (e.g., 3 L) is stored in the tub 12.

[0182] For example, when the circulation pump 30 is driven at a first rpm, the natural frequency f1 when as much washing water as V1 is stored in the tub 12 may be reduced by about 93% as compared to the natural frequency f1 when as much washing water as V4 is stored in the tub 12.

[0183] For example, when the circulation pump 30 is driven at a second rpm, the natural frequency f2 when as much washing water as V1 is stored in the tub 12 may be reduced by about 83% as compared to the natural frequency f2 when as much washing water as V4 is stored in the tub 12.

[0184] For example, when the circulation pump 30 is driven at a third rpm, the natural frequency f3 when as much washing water as V1 is stored in the tub 12 may be reduced by about 91% as compared to the natural frequency f3 when as much washing water as V4 is stored in the tub 12.

[0185] According to an embodiment, the dishwasher 1 may set a threshold range of variations in the natural frequency of the tub 12 corresponding to the driving rpm of the circulation pump 30. For example, the threshold range may be set considering the variation in the natural frequency when the amount of washing water (the volume of washing water stored in the tub 12 or the water level of washing water stored in the tub 12) is less than a predetermined level, corresponding to the driving rpm of the circulation pump 30. For example, the threshold range may be set considering the natural frequency of the tub 12 when the water level of the washing water is lower than the highest point of the sump assembly (e.g., the sump assembly 100 of FIG. 2) according to the driving rpm of the circulation pump 30.

[0186] According to an embodiment, the dishwasher 1 compares the variation (or difference) between the first natural frequency of the tub 12 obtained from sensed values produced by the vibration sensor 350 before the water supply process is initiated and the second natural frequency of the tub 12 obtained when the water supply process is finished and the driving current of the circulation pump 30 is less than the threshold, with the threshold range, and when variation exceeds the threshold range, the dishwasher 1 may determine whether the amount of washing water stored in the tub 12 is insufficient.

[0187] For example, the dishwasher 1 may determine that the amount of washing water stored in the tub 12 is sufficient when the variation (or difference) in the first natural frequency and the second natural frequency exceeds the threshold range. The dishwasher 1 may determine that the circulation pump 30 operates abnormally due to the clogging of the filter 101 even though the amount of washing water stored in the tub 12 is sufficient.

[0188] For example, the dishwasher 1 may determine that the amount of washing water stored in the tub 12 is insufficient when the variation (or difference) in the first natural frequency and the second natural frequency is within the threshold range. The dishwasher 1 may determine that the circulation pump 30 operates abnormally due to the insufficient amount of washing water stored in the tub 12.

[0189] FIG. 13 is a contour graph schematically illustrating vibration characteristics of a tub (e.g., the tub 12 of FIG. 2) in response to the water level of washing water stored in the tub 12 according to an embodiment of the disclosure.

[0190] The embodiment of FIG. 13 may be selectively combined with the embodiment of FIG. 12.

[0191] Referring to FIG. 13, the horizontal axis of the graph indicates the frequency, and the vertical axis indicates the water level of the washing water stored in the tub 12. The area divided into different patterns on the graph indicates the strength of the signal according to the output signal (e.g., the output signal 430 of FIG. 8) for the vibration characteristics of the tub 12 obtained by the dishwasher (e.g., the vibration sensor 340 of FIG. 1) from the vibration sensor (e.g., the vibration sensor 340 of FIG. 7). For example, it may be understood that the first to fourth response signals are listed in the order in which the strength of the response signal decreases.

[0192] For example, referring to the indication line indicated by the dashed line in the graph, it may be identified that the natural frequency decreases as the water level of the washing water stored in the tub 12 increases. The dishwasher 1 may calculate the natural frequency of the tub 12 corresponding to the amount of washing water stored in the tub 12 based on the vibration characteristics sensed by the vibration sensor 340. Therefore, the dishwasher 1 may determine whether the amount of washing water replenished in the tub 12 during the water supply process is sufficient based on the variation (or difference) between the natural frequency of tub 12 before the water supply process is initiated and the natural frequency of tub 12 after the water supply process is finished.

[0193] According to an embodiment, the dishwasher 1 may determine whether the amount of washing water stored in the tub 12 is sufficient based on the vibration characteristics of the tub 12 sensed by the vibration sensor 340 and indicated by sensed values produced by the vibration sensor 340, and determine whether the filter (e.g., the filter 101 of FIG. 4B) is clogged based on the driving current of the circulation pump (e.g., the circulation pump 30 of FIG. 2) indicated by a sensed value produced by the current sensor (e.g., the current sensor 350 of FIG. 7).

[0194] FIG. 14 schematically illustrates a smart home system according to an embodiment of the disclosure.

[0195] The embodiment of FIG. 14 may be selectively combined with the embodiment of FIGS. 1 to 13.

[0196] Referring to FIG. 14, the home appliance 1410 may include another home appliance, a communication module capable of communicating with a user terminal 2 or a server 3, a user interface for receiving a user input or outputting information to the user, at least one processor for controlling the operation of the home appliance 1410, and at least one memory storing a program for controlling the operation of the home appliance 1410.

[0197] According to an embodiment, the home appliance 1410 may be at least one of various types of home appliances. For example, as illustrated, the home appliance 1410 may include at least one of a dishwasher 1401 (e.g., the dishwasher 1 of FIG. 1), a refrigerator 1402, an electric range 1403, an electric oven 1404, an air conditioner 1405, a steam closet 1406, a washing machine 1407, a dryer 1408, and a microwave oven 1409, but is not limited thereto. For example, the home appliance 10 may include various types of home appliances such as a robot vacuum, a vacuum cleaner, and a television, which are not illustrated in the drawings. Further, the aforementioned home appliances are merely examples, and in addition to the aforementioned home appliances, a device that is connected to another home appliance, the user terminal 2, or the server 3 and may perform the operations described below may be included in the home appliance 1410 according to an embodiment.

[0198] According to an embodiment, the server 3 may include a communication module capable of communicating with another server, home appliance 1410 or the user terminal 2, at least one processor capable of processing data received from the other server, home appliance 1410, or user terminal 2, and at least one memory capable of storing a program for processing data or processed data. The server 3 may be implemented as various computing devices such as a workstation, a cloud, a data drive, and a data station. The server 3 may be implemented as one or more servers physically or logically divided based on functions, detailed configurations of functions, data, or the like, and may transmit and receive data and process the transmitted and received data through communication between the servers.

[0199] According to an embodiment, the server 3 may manage the user account, register the home appliance 1410 by associating the home appliance 1410 with the user account, and manage or control the registered home appliance 10. For example, the user may access the server 3 through the user terminal 2 to create a user account. The user account may be identified by an ID and a password set by the user. The server 3 may register the home appliance 1410 in the user account according to a predetermined procedure. For example, the server 3 may register, manage, and control the home appliance 1410 by connecting identification information (e.g., a serial number or a MAC address) about the home appliance 1410 to the user account. The user terminal 2 may include a communication module capable of communicating with the home appliance 1410 or the server 3, a user interface for receiving a user input or outputting information to the user, at least one processor for controlling the operation of the user terminal 2, and at least one memory storing a program for controlling the operation of the user terminal 2.

[0200] According to an embodiment, the user terminal 2 may be carried by the user or may be disposed in the user's home or office. The user terminal 2 may include, but is not limited to, a personal computer, a terminal, a mobile phone, a smart phone, a handheld device, a wearable device, or the like.

[0201] According to an embodiment, a program for controlling the home appliance 1410, i.e., an application, may be stored in the memory of the user terminal 2. The application may be sold while being stored in the user terminal 2, or may be downloaded from an external server and stored.

[0202] According to an embodiment, the user may access the server 3 to create a user account by executing the application stored in the user terminal 2, and may communicate with the server 3 based on the logged-in user account to register the home appliance 1410.

[0203] According to an embodiment, for example, when the home appliance 1410 is manipulated so that the home appliance 1410 may be connected to the server 3 according to the procedure guided by the application stored in the user terminal 2, the server 3 may register the home appliance 1410 in the user account by registering the identification information (e.g., serial number or MAC address) about the home appliance 1410 in the corresponding user account.

[0204] According to an embodiment, the user may control the home appliance 1410 using the application stored in the user terminal 2. For example, when the user logs in to the user account with the application stored in the user terminal 2, the home appliance 1410 registered in the user account appears, and when a control command for the home appliance 1410 is input, the control command may be transferred to the home appliance 1410 through the server 3.

[0205] According to an embodiment, the network may include both a wired network and a wireless network. The wired network may include a cable network, a telephone network, or the like, and the wireless network may include all networks that transmit and receive signals through radio waves. The wired network and the wireless network may be connected to each other.

[0206] According to an embodiment, the network may include a wide area network (WAN) such as the Internet, a local area network (LAN) formed around an access point (AP), and a short-range wireless network that does not pass through the AP. The short-range wireless network may include, but is not limited to, Bluetooth (IEEE 802.15.1), Zigbee (IEEE 802.15.4), Wi-Fi Direct, near field communication (NFC), and Z-wave. In the disclosure, the access point may be referred to below as a hub device 1400.

[0207] According to an embodiment, the hub device 1400 may connect the home appliance 1410 or the user terminal 2 to a WAN to which the server 3 is connected. The home appliance 1410 or the user terminal 2 may be connected to the server 3 through a WAN.

[0208] According to an embodiment, the hub device 1400 may communicate with the home appliance 1410 or the user terminal 2 using wireless communication such as Wi-Fi (Wi-Fi, IEEE 802.11), Bluetooth (Bluetooth, IEEE 802.15.1), Zigbee (IEEE 802.15.4), or the like, and may access the wide area network (WAN) using wired communication, but is not limited thereto.

[0209] According to an embodiment, the home appliance 1410 may be directly connected to the user terminal 2 or the server 3 without passing through the hub device 1400.

[0210] According to an embodiment, the home appliance 1410 may be connected to the user terminal 2 or the server 3 through a long-range wireless network or a short-range wireless network.

[0211] For example, the home appliance 1410 may be connected to the user terminal 2 through a short-range wireless network (e.g., Wi-Fi direct).

[0212] As another example, the home appliance 1410 may be connected to the user terminal 2 or the server 3 through a wide area network (WAN) using a long-range wireless network (e.g., a cellular communication module).

[0213] As another example, the home appliance 1410 may access a wide area network (WAN) using wired communication and may be connected to the user terminal 2 or the server 3 through the wide area network (WAN).

[0214] According to an embodiment, when the home appliance 1410 is able to access the wide area network (WAN) using wired communication, it may operate as an access repeater. Accordingly, the home appliance 1410 may connect another home appliance to the wide area network (WAN) to which the server 3 is connected. Further, the other home appliance may connect the home appliance 1410 to the wide area network (WAN) to which the server 3 is connected.

[0215] According to an embodiment, the home appliance 1410 may transmit information about the operation or the status to the other home appliance, the user terminal 2, or the server 3 through the network. For example, when the request is received from the server 3, when the specific event occurs in the home appliance 1410, or periodically or in real time, the home appliance 1410 may transmit information about the operation or the status to the other home appliance, the user terminal 2, or the server 3. When the information about the operation or the status is received from the home appliance 1410, the server 3 may update the stored information about the operation or the status of the home appliance 1410, and transmit the updated information about the operation and the status of the home appliance 1410 to the user terminal 2 through the network. Here, updating information may include various operations for changing existing information, such as adding new information to existing information and replacing existing information with new information.

[0216] According to an embodiment, the home appliance 1410 may obtain various information from the other home appliance, the user terminal 2, or the server 3, and provide the obtained information to the user. For example, the home appliance 1410 may obtain information related to the function of the home appliance 1410 (e.g., recipe, washing method, etc.) and various environmental information (e.g., weather, temperature, humidity, etc.) from the server 3, and output the obtained information through the user interface.

[0217] According to an embodiment, the home appliance 1410 may operate according to a control command received from the other home appliance, the user terminal 2, or the server 3. For example, when the home appliance 1410 obtains the user's prior approval to operate according to the control command of the server 3 even if there is no user input, the home appliance 1410 may operate according to the control command received from the server 3. Here, the control command received from the server 3 may include a control command input by the user through the user terminal 2 or a control command based on a predetermined condition, but is not limited thereto.

[0218] According to an embodiment, the user terminal 2 may transmit information about the user to the home appliance 1410 or the server 3 through the communication module. For example, the user terminal 2 may transmit information about the position of the user, the health condition of the user, the taste of the user, the schedule of the user, and the like to the server 3. The user terminal 2 may transmit the information about the user to the server 3 according to prior approval by the user.

[0219] According to an embodiment, the home appliance 1410, the user terminal 2, or the server 3 may determine a control command using a technology such as artificial intelligence. For example, the server 3 may receive information about the operation or the status of the home appliance 1410, receive the information about the user of the user terminal 2, process the information using technology such as artificial intelligence, and transmit the processing result or the control command to the home appliance 1410 or the user terminal 2 based on the processing result.

[0220] FIG. 15 is a signaling view schematically illustrating a process of transferring guide information for instructing management of a filter (e.g., the filter 101 of FIG. 4B) between a dishwasher 1 (e.g., the dishwasher 1 of FIG. 1 or the dishwasher 1401 of FIG. 14), a hub device 1400 (e.g., the hub device 1400 of FIG. 14), and an external device (e.g., the user terminal 2 of FIG. 14) according to an embodiment of the disclosure.

[0221] FIG. 15 may be understood as schematically illustrating a signaling view in which the dishwasher 1 determines that the filter (e.g., the filter 101 of FIG. 4B) is in the clogged state (e.g., operation 930 of FIG. 9 and/or operation 1060 of FIG. 10) and accordingly transmits a signal with the hub device 1400 and the external device 2 to transfer guide information instructing management of the filter 101 and the state of the filter 101 to the user.

[0222] The embodiment of FIG. 15 may be selectively combined with the embodiment of FIGS. 1 to 14.

[0223] Referring to FIG. 15, in step 1511, the dishwasher 1 may determine that the filter 101 is clogged. For example, step 1511 may in whole or part correspond to operation 930 of FIG. 9 and/or operation 1060 of FIG. 10.

[0224] According to an embodiment, in step 1512, the dishwasher 1 may transfer information indicating the clogging of the filter to the hub device 1400. In step 1521, the hub device 1400 may transfer the information to the external device 2. Although not shown, the dishwasher 1 may directly transfer information indicating the clogging of the filter to the external device 2 without passing through the hub device 1400.

[0225] According to an embodiment, in step 1513, the dishwasher 1 may output information indicating the clogging of the filter. In step 1522, the hub device 1400 may output information indicating the clogging of the filter. The hub device 1400 may further include a display or a speaker for outputting the information indicating the clogging of the filter. In step 1531, the external device 2 may output the information indicating the clogging of the filter. The external device 2 may further include a display or a speaker for outputting the information indicating the clogging of the filter. An embodiment showing the user interface (UI) for step 1513 is described with reference to FIG. 16.

[0226] According to an embodiment, in step 1531, in response to outputting the information indicating the clogging of the filter, the external device 2 may receive a command to stop the washing process from the user. For example, the user may enter a command to stop the washing process when the filter 101 is clogged, remove the filter 101 from the dishwasher 1, clean it, and then put it back in.

[0227] According to an embodiment, in step 1533, the external device 2 may transfer a command to stop the washing process to the hub device 1400. In step 1523, the hub device 1400 may transfer a command to stop the washing process to the dishwasher 1. Although not shown, the external device 2 may transfer a command to stop the washing process to the dishwasher 1 without passing through the hub device 1400. The embodiment showing the user interface for operation 1533 is described with reference to FIGS. 17 to 19.

[0228] According to an embodiment, in step 1514, the dishwasher 1 may stop the washing process in response to receiving a user input for stopping the washing process.

[0229] FIG. 16 illustrates an input/output unit (e.g., the input/output unit 200 of FIG. 7) of a dishwasher (e.g., the dishwasher 1 of FIG. 1) according to an embodiment of the disclosure.

[0230] The embodiment of FIG. 16 may be selectively combined with the embodiment of FIGS. 1 to 15.

[0231] Referring to FIG. 16, the illustrated input/output unit 200 may receive a user input for the dishwasher 1 and display information about the operation state or whether the dishwasher 1 is driven normally. The input/output unit 200 may be implemented as a touch display panel (TSP) capable of receiving a touch input.

[0232] According to an embodiment, the input/output unit 200 may include a first display area 1610 and a second display area 1620. A button for receiving the user's input, an icon for visually displaying information about the operating state of the dishwasher 1, and an LED indicator for visually displaying information about the operating state by light emission may be disposed in each of the first display area 1610 and the second display area 1620.

[0233] According to an embodiment, a first filter icon 1611 instructing the management of the filter (e.g., the filter 101 of FIG. 4B) and a first LED indicator 1613 configured to emit light according to an abnormal operation of the dishwasher 1 may be disposed in the first display area 1610.

[0234] According to an embodiment, when the dishwasher 1 determines that the filter 101 is clogged, the dishwasher 1 may control the first filter icon 1611 and the first LED indicator 1613 to emit light. For example, the dishwasher 1 may control the first filter icon 1611 and the first LED indicator 1613 to emit light every predetermined time period.

[0235] According to an embodiment, a second filter icon 1621 instructing the management of the filter 101 and a second LED indicator 1623 configured to emit light according to an abnormal operation of the dishwasher 1 may be disposed in the second display area 1620.

[0236] According to an embodiment, if the dishwasher 1 determines that the filter 101 is clogged, the dishwasher 1 may control the second filter icon 1621 and the second LED indicator 1623 to emit light. For example, the dishwasher 1 may control the second filter icon 1621 and the second LED indicator 1613 to emit light every predetermined time period.

[0237] According to an embodiment, the dishwasher 1 may detect whether the filter 101 is in an abnormal state and adaptively guide the user to manage the filter 101 to the user in response to whether the filter 101 is clogged.

[0238] FIG. 17 illustrates an embodiment of displaying guide information instructing management of a filter (e.g., the filter 101 of FIG. 4B) of dishwasher (e.g., the dishwasher 1 of FIG. 1 and/or the dishwasher 1401 of FIG. 14) by an external device (e.g., the user terminal 2 of FIG. 14) according to an embodiment of the disclosure.

[0239] FIG. 18 illustrates a first user interface of guide information displayed on an external device 2 according to an embodiment of the disclosure.

[0240] FIG. 19 illustrates a second user interface of guide information displayed on an external device 2 according to an embodiment of the disclosure.

[0241] For convenience of description, the external device 2 shown in FIGS. 17 to 19 will be assumed to be a user terminal (e.g., a smartphone). However, the external device 2 of FIGS. 17 to 19 is not limited to the user terminal, but may also be applied to home appliances (e.g., the home appliance 1400 of FIG. 14) that is communicatively connected to the dishwasher 1 to transmit and receive data to and from the dishwasher 1, and may also be applied to various types of wearable devices (e.g., smart watches, smart rings, smart glasses, head mounted devices, and ear buds) that may be wiredly and/or wirelessly connected to the user terminal.

[0242] The embodiments of FIGS. 17 to 19 may be selectively combined with the embodiments of FIGS. 1 to 16.

[0243] Referring to FIG. 17, the external device 2 may receive guide information instructing the management of the filter 101 of the dishwasher 1 from the dishwasher 1 and/or the hub device (e.g., the hub device 1400 of FIG. 14). The external device 2 may display the guide information on the display 1700.

[0244] According to an embodiment, the external device 2 may display the guide information on the first user interface 1710 or the guide information on the second user interface 1720.

[0245] According to an embodiment, the first user interface 1710 may be displayed when slid or swiped downward with one point of the display 1710 touched. For example, the first user interface 1710 may display operation information about the external device 2 or information about the message received by the external device 2, or information about the operation state of a home appliance (e.g., the home appliance 1410 of FIG. 14) connected to the external device 2.

[0246] According to an embodiment, the second user interface 1720 may display the operation state for the external device 2 and a device (e.g., the home appliance 1410 or the hub device 1400) connected to the external device 2. For example, the second user interface 1720 may be displayed on the display 1700 in response to being wirelessly connected to the dishwasher 1, or may be displayed on the display 1700 in response to receiving guide information transmitted by the dishwasher 1. For example, the second user interface 1720 may be displayed in a manner of being popped up in a predetermined area on the display 1700 in response to the occurrence of the above-described event.

[0247] Hereinafter, a description of a specific embodiment of the first user interface 1710 is described in connection with FIG. 18, and a description of a specific embodiment of the second user interface 1720 is described in connection with FIG. 19.

[0248] Referring to FIG. 18, the first user interface 1710 may include a first object 1810 indicating that it is an indoor home appliance connected to the hub device 1400 and a second object 1820 indicating guide information instructing the management of the dishwasher 1.

[0249] According to an embodiment, in response to receiving a click or a touch to the first user interface 1710, a detailed setting screen for inputting a command for the operation of the dishwasher 1 may be displayed on the display 1700. For example, on the detailed setting screen, the user may input a command to stop the washing process of the dishwasher 1.

[0250] Referring to FIG. 19, the second user interface 1720 may include a first object 1910 indicating the type of the indoor home appliance connected to the hub device 1400, a second object 1920 indicating an abnormal operation state of the dishwasher 1, and a third object 1930 for receiving the user input for the operation of the dishwasher 1.

[0251] According to an embodiment, the third object 1930 may include a 3-1th object 1931 for receiving a user input for instructing to stop the washing process being performed by the dishwasher 1, a 3-2th object 1933 for receiving a user input for instructing to continue performing the washing process being performed by the dishwasher 1, and a 3-3th object 1935 for receiving a user input for detailed settings of the operation of the dishwasher 1.

[0252] For example, in response to receiving an input to the 3-1th object 1931, the external device 2 may transfer a signal for instructing to stop the washing process to the hub device 1400 and/or the dishwasher 1 (e.g., step 1533 of FIG. 15).

[0253] For example, in response to receiving an input to the 3-2th object 1933, the external device 2 may transfer a signal for instructing to continue the washing process to the hub device 1400 and/or the dishwasher 1.

[0254] For example, in response to receiving an input to the 3-3th object 1935, the detailed setting screen for inputting a command for the operation of the dishwasher 1 may be displayed on the display 1700.

[0255] For example, when reception for the 3-1th to 3-3th objects 1931, 1933, and 1935 is not responded for a predetermined period of time, the external device 2 may transfer a signal for instructing to continue the washing process to the hub device 1400 and/or the dishwasher 1.

[0256] According to an embodiment, the dishwasher 1 may detect whether the filter 101 is in an abnormal state and adaptively guide the user to manage the filter 101 through the external device 2 in response to whether the filter 101 is clogged.

[0257] The dishwasher 1 according to an embodiment of the disclosure relates to providing a control method for determining whether the filter 101 is clogged.

[0258] The dishwasher 1 according to an embodiment of the disclosure may detect the degree of clogging of the filter based on the vibration characteristics of the tub indicated by sensed values produced by the vibration sensor 340 disposed near the sump assembly 100.

[0259] The dishwasher 1 according to an embodiment of the disclosure may adaptively provide a notification for instructing the user to manage the filter in response to the degree of clogging of the filter 101.

[0260] A dishwasher (e.g., the dishwasher 1 of FIG. 1) according to an embodiment of the disclosure may comprise a tub 12, a sump assembly 100 disposed under the tub 12 and storing washing water, a circulation pump 30 pumping and circulating the washing water stored in the sump assembly 100, at least one jet device 41, 42, 43 jetting the washing water pumped by the circulation pump 30 into the tub 12, a filter 101 disposed under the tub 12 and filtering a foreign object flowing inside the tub 12, a current sensor 350 to sense a driving current input to the circulation pump 30, a vibration sensor 340 to sense a vibration of the tub 12 generated by driving of the circulation pump 30, and a controller 310 configured to detect whether the filter 101 is clogged based on sensed values produced by the current sensor 350 and the vibration sensor 340. The controller 310 may be configured to obtain a first natural frequency of the tub 12 from a sensed value produced by the vibration sensor 340, obtain a second natural frequency of the tub 12 from a sensed value produced the vibration sensor 350 in response to the driving current of the circulation pump 30 indicated by a sensed value produced by the current sensor 350 being less than a reference current, and determine that the filter 101 is in a clogged state when a variation (or difference) in the second natural frequency with respect to the first natural frequency exceeds a preset threshold range.

[0261] In the dishwasher 1 according to an embodiment of the disclosure, the vibration sensor 340 may be disposed under the sump assembly 100.

[0262] In the dishwasher 1 according to an embodiment of the disclosure, the vibration sensor 340 may be disposed adjacent to the circulation pump 30.

[0263] In the dishwasher 1 according to an embodiment of the disclosure, the vibration sensor 340 may be configured to detect a different vibration corresponding to an amount of the washing water collected in the tub 12.

[0264] In the dishwasher 1 according to an embodiment of the disclosure, the vibration sensor 340 may include an accelerometer or a strain gauge.

[0265] In the dishwasher 1 according to an embodiment of the disclosure, the first natural frequency may be a natural frequency of the tub 12 obtained in response to initiation of a water supply process included in a washing cycle, and the second natural frequency may be a natural frequency of the tub 12 obtained at any time after the water supply process is finished.

[0266] The dishwasher 1 according to an embodiment of the disclosure may further comprise an actuator 370 attached to a surface of the tub 12 to generate a vibration for the tub 12. The controller 310 may be configured to obtain the first natural frequency and the second natural frequency from the vibration sensor 340 in response to the vibration generated from the actuator 370.

[0267] In the dishwasher 1 according to an embodiment of the disclosure, the controller 310 may be configured to, when a difference between the first natural frequency and the second natural frequency is within a preset threshold range, determine that a water level of the washing water stored in the tub 12 is lower than a reference water level.

[0268] In the dishwasher 1 according to an embodiment of the disclosure, the controller 310 may be configured to, when a number of times in which the washing water is supplied to the tub 12 is less than a threshold number, transfer a control signal to the circulation pump 30 to supply a predetermined volume of the washing water to the tub 12.

[0269] In the dishwasher 1 according to an embodiment of the disclosure, the reference water level may be set to a water level when the washing water collected in the tub 12 reaches an uppermost end of the sump assembly 100.

[0270] The dishwasher 1 according to an embodiment of the disclosure may further comprise a display 200. The controller 310 may be configured to, when the filter 101 is determined to be clogged, display information indicating the clogging of the filter on the display 200.

[0271] The dishwasher 1 according to an embodiment of the disclosure may further comprise a communication unit (or transceiver) 330 capable of wireless communication with an external device 2. The controller 310 may be configured to, when the filter 101 is determined to be clogged, transfer guide information instructing management of the filter 101 to the external device 2 through the communication unit 330.

[0272] A method for controlling a dishwasher 1 according to an embodiment of the disclosure may comprise obtaining (920, 1010) a first natural frequency of a tub 12 based on a sensed value produced by a vibration sensor 340, obtaining (920, 1040) a second natural frequency of the tub 12 based on a sensed value produced by the vibration sensor 340 in response to a driving current of a circulation pump 30 indicated by a sensed value produced by a current sensor 350 being less than a reference current (910, 1020, 1030), and determining (1070) that the filter is clogged when a variation in the second natural frequency with respect to the first natural frequency exceeds a preset threshold range (1050).

[0273] In the method for controlling the dishwasher 1 according to an embodiment of the disclosure, the vibration sensor 350 may be configured to detect a different vibration corresponding to an amount of the washing water collected in the tub 12.

[0274] In the method for controlling the dishwasher 1 according to an embodiment of the disclosure, the first natural frequency may be a natural frequency of the tub 12 obtained in response to initiation of a water supply process included in a washing cycle, and the second natural frequency may be a natural frequency of the tub 12 obtained at any time after the water supply process is finished.

[0275] The method for controlling the dishwasher 1 according to an embodiment of the disclosure may further comprise, when a difference between the first natural frequency and the second natural frequency is within a preset threshold range, determining (1081) that a water level of the washing water stored in the tub 12 is lower than a reference water level.

[0276] The method for controlling the dishwasher 1 according to an embodiment of the disclosure may further comprise, when a number of times in which the washing water is supplied to the tub 12 is less than a threshold number 1083, supplying (1085) a predetermined volume of the washing water to the tub 12.

[0277] In the method for controlling the dishwasher 1 according to an embodiment of the disclosure, the reference water level may be set to a water level when the washing water collected in the tub 12 reaches an uppermost end of the sump assembly 100.

[0278] The method for controlling the dishwasher 1 according to an embodiment of the disclosure may further comprise, when the filter 101 is determined to be clogged, displaying (1070) information indicating the clogging of the filter on a display 200.

[0279] The method for controlling the dishwasher 1 according to an embodiment of the disclosure may further comprise, when the filter 101 is determined to be clogged, transferring guide information instructing management of the filter 101 to an external device 2.