DRYER APPLIANCE AND METHOD FOR IGNITION FAILURE DETECTION

Abstract

A dryer appliance and method for operation are provided, the method including measuring temperature of air for drying laundry articles; transmitting a first control signal for operating the ignition source to generate heat for heating air for drying laundry articles; measuring, over a period of time following transmission of the control signal, temperature of air for drying laundry articles; and determining an operational state of the heating system based on measuring the temperature of air, wherein the operational state includes a normal ignition state or an ignition failure state, wherein the normal ignition state corresponds to an increase in temperature of air during the period of time, and wherein the ignition failure state corresponds to a substantially unchanged temperature of air.

Claims

1. A dryer appliance comprising: a cabinet; a drum rotatably mounted within the cabinet, the drum defining a chamber for the receipt of laundry articles for drying; a heating system configured in fluid communication with the chamber at the drum, the heating system comprising an ignition source configured to ignite gaseous fuel for heating air provided to the chamber for drying laundry articles; a temperature sensor positioned downstream of the ignition source, the temperature sensor configured to determine temperature of air in fluid communication with the chamber at the drum; and a controller configured to store instructions that, when executed, causes the dryer appliance to perform operations, the operations comprising: measuring, via the temperature sensor, temperature of air for drying laundry articles; transmitting a first control signal for operating the ignition source to generate heat for heating air for drying laundry articles; measuring, via the temperature sensor and over a period of time following transmission of the control signal, temperature of air for drying laundry articles; and determining an operational state of the heating system based on measuring the temperature of air, wherein the operational state comprises a normal ignition state or an ignition failure state, wherein the normal ignition state corresponds to an increase in temperature of air during the period of time, and wherein the ignition failure state corresponds to a substantially unchanged temperature of air.

2. The dryer appliance of claim 1, comprising: transmitting a second control signal to discontinue the dryer cycle when ignition failure state is determined.

3. The dryer appliance of claim 1, comprising: transmitting a communication signal corresponding to ignition failure.

4. The dryer appliance of claim 1, wherein determining the operational state of the heating system comprises determining, via the temperature sensor, a maximum temperature within the period of time.

5. The dryer appliance of claim 1, wherein determining the operational state of the heating system comprises determining, via the temperature sensor, a maximum temperature after the period of time.

6. The dryer appliance of claim 1, wherein measuring temperature of air for drying laundry articles comprises obtaining a rolling average of temperature over the period of time.

7. The dryer appliance of claim 6, wherein determining the operational state of the heating system comprises determining whether the rolling average of temperature over the period of time exceeds a threshold temperature, wherein exceeding the threshold temperature corresponds to normal ignition state, and wherein ignition failure state corresponds to the rolling average temperature below the threshold temperature.

8. The dryer appliance of claim 1, wherein the normal ignition state corresponds to an increase in temperature of air of at least 5 degrees Fahrenheit during the period of time, and wherein the substantially unchanged temperature corresponding to the ignition failure state is less than 5 degrees Fahrenheit change during the period of time.

9. The dryer appliance of claim 1, wherein the normal ignition state corresponds to an increase in temperature of air of at least 20 degrees Fahrenheit during the period of time, and wherein the substantially unchanged temperature corresponding to the ignition failure state is less than 20 degrees Fahrenheit change during the period of time.

10. The dryer appliance of claim 1, wherein the period of time is up to approximately 60 seconds from transmission of the first control signal for operating the ignition source to generate heat for heating air for drying laundry articles.

11. The dryer appliance of claim 1, wherein measuring the temperature of air for drying laundry articles comprises obtaining an air temperature prior to transmitting the first control signal, and wherein the operations comprise: comparing the measured temperature of air to a temperature range to determine a functional state of the temperature sensor.

12. A computer-implemented method for operating a dryer appliance, the method comprising: measuring temperature of air for drying laundry articles; transmitting a first control signal for operating the ignition source to generate heat for heating air for drying laundry articles; measuring, over a period of time following transmission of the control signal, temperature of air for drying laundry articles; and determining an operational state of the heating system based on measuring the temperature of air, wherein the operational state comprises a normal ignition state or an ignition failure state, wherein the normal ignition state corresponds to an increase in temperature of air during the period of time, and wherein the ignition failure state corresponds to a substantially unchanged temperature of air.

13. The method of claim 12, comprising: transmitting a second control signal to discontinue the dryer cycle when ignition failure is determined.

14. The method of claim 12, comprising: transmitting a communication signal corresponding to ignition failure.

15. The method of claim 12, wherein determining the operational state of the heating system comprises determining a maximum temperature within the period of time.

16. The method of claim 12, wherein determining the operational state of the heating system comprises determining a maximum temperature after the period of time.

17. The method of claim 12, wherein measuring temperature of air for drying laundry articles comprises obtaining a rolling average of temperature over the period of time.

18. The method of claim 17, wherein determining the operational state of the heating system comprises determining whether the rolling average of temperature over the period of time exceeds a threshold temperature, wherein exceeding the threshold temperature corresponds to normal ignition state, and wherein ignition failure state corresponds to rolling average temperature below the temperature threshold.

19. The method of claim 12, wherein the normal ignition state corresponds to an increase in temperature of air of at least 5 degrees Fahrenheit during the period of time, and wherein the substantially unchanged temperature corresponding to the ignition failure state is less than 5 degrees Fahrenheit change during the period of time.

20. The method of claim 12, wherein the period of time is up to approximately 60 seconds from transmission of the first control signal for operating the ignition source to generate heat for heating air for drying laundry articles.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0009] A full and enabling disclosure of the present invention, including the best mode thereof, directed to one of ordinary skill in the art, is set forth in the specification, which makes reference to the appended figures.

[0010] FIG. 1 provides a perspective view of a dryer appliance in accordance with an example embodiment of the present disclosure.

[0011] FIG. 2 provides a perspective view of the example dryer appliance of FIG. 1 with portions of a cabinet of the dryer appliance removed to reveal various components of the dryer appliance.

[0012] FIG. 3 provides a flowchart outlining exemplary steps of a method for operating a dryer appliance in accordance with aspects of the present disclosure.

DETAILED DESCRIPTION

[0013] Reference now will be made in detail to embodiments of the invention, one or more examples of which are illustrated in the drawings. Each example is provided by way of explanation of the invention, not limitation of the invention. In fact, it will be apparent to those skilled in the art that various modifications and variations can be made in the present invention without departing from the scope or spirit of the invention. For instance, features illustrated or described as part of one embodiment can be used with another embodiment to yield a still further embodiment. Thus, it is intended that the present invention covers such modifications and variations as come within the scope of the appended claims and their equivalents.

[0014] As used herein, the term or is generally intended to be inclusive (i.e., A or B is intended to mean A or B or both). In addition, here and throughout the specification and claims, range limitations may be combined or interchanged. Such ranges are identified and include all the sub-ranges contained therein unless context or language indicates otherwise. For example, all ranges disclosed herein are inclusive of the endpoints, and the endpoints are independently combinable with each other. The singular forms a, an, and the include plural references unless the context clearly dictates otherwise. The word exemplary is used herein to mean serving as an example, instance, or illustration. In addition, references to an embodiment or one embodiment does not necessarily refer to the same embodiment, although it may. Any implementation described herein as exemplary or an embodiment is not necessarily to be construed as preferred or advantageous over other implementations. Moreover, each example is provided by way of explanation of the invention, not limitation of the invention. In fact, it will be apparent to those skilled in the art that various modifications and variations can be made in the present invention without departing from the scope of the invention. For instance, features illustrated or described as part of one embodiment can be used with another embodiment to yield a still further embodiment. Thus, it is intended that the present invention covers such modifications and variations as come within the scope of the appended claims and their equivalents.

[0015] Embodiments of a dryer appliance and method for operation are provided that address one or more of the aforementioned issues. Embodiments of the dryer appliance include a controller configured to execute steps of a method for ignition failure detection. Embodiments of the method include measuring air temperature of air fed to a dryer chamber at which laundry articles are to be dried. A control signal is transmitted to operate the heating assembly to generate heat, such as warming up or firing an igniter. Air temperature is measured over a period of time following transmission of the control signal. The method determines a normal ignition (e.g., ignition of gas heater) when air temperature increases within the period of time. The method determines ignition failure when air temperature is unchanged during the period of time. In some embodiments, the method includes transmitting a control signal to discontinue the dryer cycle when ignition failure is determined or transmitting a communication signal corresponding to ignition failure.

[0016] Embodiments of the dryer appliance and method for operation provided herein may decrease product complexity, product cost, and development time relative to appliances and methods that utilize additional or multiple sensors, such as light sensors, photoresistor sensors, computer vision, or air quality sensors for determining combustion gases.

[0017] Turning now to the figures, FIG. 1 provides dryer appliance 10 according to an example embodiment of the present subject matter. FIG. 2 provides another perspective view of dryer appliance 10 with a portion of a cabinet or housing 12 of dryer appliance 10 removed in order to show certain components of dryer appliance 10. While described in the context of a specific embodiment of dryer appliance 10, using the teachings disclosed herein, it will be understood that dryer appliance 10 is provided by way of example only. Other dryer appliances having different appearances and different features may also be utilized with the present subject matter as well.

[0018] Cabinet 12 includes a front panel 14, a rear panel 16, a pair of side panels 18 and 20 spaced apart from each other by front and rear panels 14 and 16, a bottom panel 22, and a top cover 24. Within cabinet 12 is a drum or container 26 mounted for rotation about a substantially horizontal axis. Drum 26 defines a chamber 25 for receipt of articles of clothing for drying. Drum 26 extends between a front portion 37 and a back portion 38.

[0019] As used herein, the term clothing includes but need not be limited to fabrics, textiles, garments, linens, papers, or other items from which the extraction of moisture is desirable. Furthermore, the term load or laundry load refers to the combination of clothing that may be washed together in a washing machine or dried together in a dryer appliance (e.g., clothes dryer) and may include a mixture of different or similar articles of clothing of different or similar types and kinds of fabrics, textiles, garments and linens within a particular laundering process.

[0020] A motor 31 is configured for rotating drum 26 about the horizontal axis, e.g., via a pulley and a belt (not shown). Drum 26 is generally cylindrical in shape, having an outer cylindrical wall 28 and a front flange or wall 30 that defines an opening 32 of drum 26, e.g., at front portion 37 of drum 26, for loading and unloading of articles into and out of chamber 25 of drum 26. A plurality of lifters or baffles (e.g., baffles 27) are provided within chamber 25 of drum 26 to lift articles therein and then allow such articles to tumble back to a bottom of drum 26 as drum 26 rotates. Baffles 27 may be mounted to drum 26 such that baffles 27 rotate with drum 26 during operation of dryer appliance 10.

[0021] In some embodiments, each baffle 27 includes a baffle body 112 that defines a lifting face 114 and a non-lifting face 116. For example, in the instance in which the drum 26 rotates counter-clockwise from the perspective of a viewer situated in front of the opening 32, baffle 27 will have a lifting face 114. Likewise, in the instance in which the drum 26 rotates counter-clockwise from the perspective of a viewer situated in front of the opening 32, baffle 27 will have a non-lifting face 116. Thus, lifting face 114 and non-lifting face 116 may face opposite each other on each baffle 27.

[0022] In some embodiments, the drum may reverse rotational directions during portions of various drying operations. In such embodiments, for example, the face of each baffle that performs lifting functionality for a majority of the operation time may be designated as the lifting face. As another example, the face of each baffle that performs lifting functionality during a critical period in which sensing of load moisture content is most relevant and scrutinized (e.g., the final period of drying) may be designated as the lifting face.

[0023] Drum 26 also includes a back or rear wall 34, e.g., at back portion 38 of drum 26. Rear wall 34 may be fixed or may be rotatable. A supply duct 41 is mounted to rear wall 34 and receives heated air that has been heated by a heating assembly or system 40. A temperature sensor 50 is positioned to obtain a measurement or calculation of temperature of air entering the chamber 25. For instance, the temperature sensor 50 may be included at heating system 40, at supply duct 41, or at another portion of a flowpath between the heating system 40 and the chamber 25. The temperature sensor 50 may include any appropriate device for measuring, calculating, or determining a temperature of air entering the chamber 25. In various embodiments, the temperature sensor 50 is positioned to obtain a temperature of air downstream of an ignition source 54, such as to obtain a temperature of heated air to be provided to the chamber 25. In various embodiments, the temperature sensor 50 is a thermistor, a thermocouple, or other device appropriate for measuring or determining temperature of air provided to the chamber 25. The ignition source 54 may include a heater igniter bulb, a spark igniter, or other appropriate device for igniting gaseous fuel for heating air for drying laundry articles at the chamber 25.

[0024] Motor 31 is also in mechanical communication with an air handler 48 such that motor 31 rotates a fan 49, e.g., a centrifugal fan, of air handler 48. Air handler 48 is configured for drawing air through chamber 25 of drum 26, e.g., in order to dry articles located therein. In alternative example embodiments, dryer appliance 10 may include an additional motor (not shown) for rotating fan 49 of air handler 48 independently of drum 26.

[0025] Drum 26 is configured to receive heated air that has been heated by a heating assembly 40, e.g., in order to dry damp articles disposed within chamber 25 of drum 26. For example, heating assembly 40 may include a heating element (not shown), such as a gas burner, an electrical resistance heating element, or heat pump, for heating air. As discussed above, during operation of dryer appliance 10, motor 31 rotates drum 26 and fan 49 of air handler 48 such that air handler 48 draws air through chamber 25 of drum 26 when motor 31 rotates fan 49. In particular, ambient air enters heating assembly 40 via an inlet 51 due to air handler 48 urging such ambient air into inlet 51. Such ambient air is heated within heating assembly 40 and exits heating assembly 40 as heated air. Air handler 48 draws such heated air through supply duct 41 to drum 26. The heated air enters drum 26 through a plurality of outlets of supply duct 41 positioned at rear wall 34 of drum 26.

[0026] Within chamber 25, the heated air may accumulate moisture, e.g., from damp clothing disposed within chamber 25. In turn, air handler 48 draws moisture saturated air through a screen filter (not shown) which traps lint particles. Such moisture statured air then enters an exit duct 46 and is passed through air handler 48 to an exhaust duct 52. From exhaust duct 52, such moisture statured air passes out of dryer appliance 10 through a vent 53 defined by cabinet 12. After the clothing articles have been dried, they are removed from the drum 26 via opening 32. A door 33 provides for closing or accessing drum 26 through opening 32.

[0027] One or more selector inputs 70, such as knobs, buttons, touchscreen interfaces, etc., may be provided or mounted on a cabinet backsplash a cabinet backsplash 71 and is in communication with a processing device or controller 56. Signals generated in controller 56 operate motor 31 and heating assembly 40 in response to the position of selector knobs 70. Alternatively, a touch screen type interface may be provided. As used herein, processing device or controller may refer to one or more microprocessors, microcontroller, ASICS, or semiconductor devices and is not restricted necessarily to a single element. The controller may be programmed to operate dryer appliance 10 by executing instructions stored in memory. The controller may include, or be associated with, one or more memory elements such as for example, RAM, ROM, or electrically erasable, programmable read only memory (EEPROM). For example, the instructions may be software or any set of instructions that when executed by the processing device, cause the processing device to perform operations.

[0028] Referring now to FIG. 3, a flowchart outlining steps of a method for operating a dryer appliance is provided (hereinafter, method 1000). Steps of the method 1000 may be stored as instructions at a computing device (e.g., controller 56) and executed as operations by a gas heater dryer appliance, such as, but not limited to, embodiments of appliance 10 depicted and described herein.

[0029] Method 1000 includes at 1010 measuring (e.g., via temperature sensor 50) temperature of air for drying laundry articles. Method 1000 at 1010 may include measuring temperature of air to be provided to the chamber at which laundry articles are positioned (e.g., chamber 25). Method 1000 at 1010 may include obtaining a first air temperature measurement prior to igniting, or attempting to ignite, gases for heating the air for drying laundry articles.

[0030] Method 1000 includes at 1020 transmitting a first control signal for operating the ignition source (e.g., ignition source 54) to generate heat for heating air for drying laundry articles. Method 1000 at 1020 may generally command heat generation at a igniter bulb or command a spark at a spark igniter, or other command for igniting gases for heating the air for drying laundry articles.

[0031] Method 1000 includes at 1030 measuring (e.g., via temperature sensor 50), over a period of time following transmission of the first control signal, temperature of air for drying laundry articles. Method 1000 at 1030 may include obtaining a second air temperature measurement after commanding ignition of gases for heating the air for drying laundry articles. In some embodiments, the period of time extends for up to twenty (20) seconds from transmission of the first control signal, or up to thirty (30) seconds from transmission of the first control signal, or up to forty (40) seconds from transmission of the first control signal, or up to fifty (50) seconds from transmission of the first control signal, or up to sixty (60) seconds from transmission of the first control signal. In various embodiments, the ignition source may take up to twenty (20) seconds to heat up (e.g., an igniter bulb) to ignite the gases for heating the drying air. In still various embodiments, the period of time includes a period of time over which the ignition source may ignite the gases and a period of time over which a temperature rise following gas ignition may be detected.

[0032] Method 1000 includes at 1040 determining an operational state of the heating system based on measuring the temperature of air. The operational state includes a normal ignition state or an ignition failure state. The normal ignition state corresponds to an increase in temperature of air during the period of time. The ignition failure state corresponds to a substantially unchanged temperature of air, such as over the period of time, or following the period of time over which ignition and temperature rise should be detected when in the normal ignition state.

[0033] In various embodiments, the normal ignition state corresponds to an increase in temperature of air at or over a threshold temperature or change in temperature. The change in temperature is at least approximately 5 degrees Fahrenheit during the period of time (e.g., relative to an initial temperature measurement, such as at step 1010). In still various embodiments, the change in temperature is at least 10 degrees Fahrenheit during the period of time, or at least 15 degrees Fahrenheit during the period of time, or at least 20 degrees Fahrenheit during the period of time. Below the temperature threshold, the temperature can be considered substantially unchanged, such as corresponding to the ignition failure state.

[0034] In still various embodiments, method 1000 at 1030 includes obtaining a rolling average of temperature over the period of time. Method 1000 at 1040 may include determining whether the rolling average of temperature over the period of time exceeds the threshold temperature. Exceeding the threshold temperature corresponds to normal ignition state, such as described above. Ignition failure state corresponds to the rolling average temperature below the threshold temperature.

[0035] In still yet various embodiments, method 1000 at 1040 includes determining a maximum temperature within, or after, the period of time (e.g., via temperature sensor 50). For instance, determining the maximum temperature may include a comparing to a discrete temperature value to determine whether the operational state is the normal ignition state or the ignition failure state. In another instance, the discrete temperature value may correspond to a threshold temperature. Comparing to the threshold temperature as the discrete temperature value may facilitate reduced data and computational usage in contrast to monitored or dynamic temperature measurements or calculations (e.g., for averages).

[0036] Embodiments of the method 1000 may include one or more iterations, such as iterations of steps 1020, 1030, and 1040, and comparisons to initial temperature measurements (e.g., at 1010). Iterative performance of the method 1000 may mitigate false negatives or false positives. For instance, iterative performance of the method 1000 may mitigate or avoid false negatives or positives that may relate to a late ignition of the heating gases, which may lead to a late start to temperature rise and a false ignition failure determination if the temperature rise or threshold temperature is not exceeded. In some embodiments, method 1000 may include any appropriate quantity of iterations, such as, but not limited to, one, or two, or three iterations.

[0037] In some embodiments, method 1000 includes at 1050 transmitting a second control signal to discontinue the dryer cycle when ignition failure state is determined. The controller (e.g., controller 56) may transmit the second control signal to one or more operational components for operating a dryer cycle, such as, but not limited to, the motor (e.g., motor 31) or the heating system (e.g., heating system 40).

[0038] In still some embodiments, method 1000 includes at 1060 transmitting a communication signal corresponding to ignition failure when ignition failure state is determined. The communication signal may include a visual or audio message to a user or technician communicating ignition failure, ignition source failure (e.g., ignition source 54), heating system failure (e.g., heating system 40), or temperature sensor failure (e.g., temperature sensor 50).

[0039] In still yet some embodiments, method 1000 includes at 1015 comparing the measured temperature of air obtained at 1010 to a temperature range. Method 1000 at 1015 may determine a functional state of the temperature sensor, such as whether the temperature sensor is functioning properly prior to performing additional steps of the method 1000. For instance, the temperature range may include at least approximately 50 degrees Fahrenheit, or at least approximately 60 degrees Fahrenheit, or another appropriate temperature as may be indicative of room temperature or temperature at the dryer appliance. The temperature range may form a minimum threshold, such as described above, or may further include an upper limit, such as up to approximately 85 degrees Fahrenheit.

[0040] Embodiments of the dryer appliance 10 and method 1000 for operation provided herein may beneficially and advantageously decrease product complexity, product cost, and development time relative to appliances and methods that utilize additional or multiple sensors, such as light sensors, photoresistor sensors, computer vision, or air quality sensors for determining combustion gases.

[0041] This written description uses examples to disclose the invention, including the best mode, and also to enable any person skilled in the art to practice the invention, including making and using any devices or systems and performing any incorporated methods. The patentable scope of the invention is defined by the claims, and may include other examples that occur to those skilled in the art. Such other examples are intended to be within the scope of the claims if they include structural elements that do not differ from the literal language of the claims, or if they include equivalent structural elements with insubstantial differences from the literal languages of the claims.