Refrigeration appliance with a noise sensor

Abstract

A refrigeration device has an electrical device part which emits noise during operation. A controller operates the electrical device part in a normal operating power range. A noise sensor detects an intensity of the emitted noise from the electrical device part. The controller is configured to change an operating power of the electrical device part within the normal operating power range and to determine a minimum value of the noise intensity which is detected by the noise sensor and to determine a noise-reduced operating power in order to operate the electrical device part at the noise-reduced operating power.

Claims

1. A refrigeration appliance, comprising: an electrical component, which emits noise during operation, said electrical component having a normal operating power range and a maximum operating power within the normal operating power range; a noise sensor for detecting a noise intensity of the noise emitted by said electrical component; a controller for operating said electrical component in the normal operating power range, said controller being configured to change an operating power of said electrical component within the normal operating power range, to determine a a plurality of minima for the noise intensity detected by said noise sensor within the normal operating power range; and said controller being configured to determine a noise-reduced operating power based on the minimum that corresponds to an operating power of said electrical component that lies within a tolerance range of the maximum operating power, and to operate said electrical component with the noise-reduced operating power.

2. The refrigeration appliance according to claim 1, wherein the normal operating power range includes a lower operating power point and an upper operating power point, which delimit the normal operating power range, and said controller is configured to change the operating power of said electrical component from the lower operating power point to the upper operating power point, in order to determine the minimum for the detected noise intensity.

3. The refrigeration appliance according to claim 1, wherein the noise-reduced operating power corresponds to the operating power of said electrical component at which the detected noise intensity is below a predefined intensity threshold value, and wherein the refrigeration appliance further comprises a manual operating facility for enabling a user of the refrigeration appliance to change the intensity threshold value.

4. The refrigeration appliance according to claim 1, wherein: said controller is configured to change the operating power of said electrical component within the normal operating power range and to determine the minimum for the detected noise intensity and to determine the noise-reduced operating power during a first time segment; and said controller is configured to operate said electrical component with the noise-reduced operating power during a second time segment following the first time segment.

5. The refrigeration appliance according to claim 4, wherein said controller is configured to determine the noise-reduced operating power after the refrigeration appliance has been connected to an electrical power supply, or said controller is configured to determine the noise-reduced operating power after periodically repeated operating time intervals.

6. The refrigeration appliance according to claim 5, wherein said controller is configured to repeat the first time segment, if said controller fails to determine any change in the noise-reduced operating power during the first time segment and said controller is configured to extend a duration of the periodically repeated operating time intervals if said controller fails to determine any change in noise-reduced operating power after the two successive first time segments.

7. The refrigeration appliance according to claim 1, which comprises a refrigerant circuit for cooling a cooling region of the refrigeration appliance, said electrical component forming a part of said refrigerant circuit.

8. The refrigeration appliance according to claim 7, wherein said electrical component is a refrigerant compressor or a fan for cooling a refrigerant condenser of said refrigerant circuit.

9. The refrigeration appliance according to claim 1, wherein said electrical component comprises a movable flap for closing an air duct of the refrigeration appliance or a valve for closing a fluid-conveying line within the refrigeration appliance.

10. The refrigeration appliance according to claim 1, wherein said noise sensor comprises an acoustic sensor for detecting noise emitted by said electrical component or a vibration sensor for detecting vibrations emitted by said electrical component.

11. The refrigeration appliance according to claim 1, wherein said noise sensor comprises a piezo vibration sensor.

12. The refrigeration appliance according to claim 1, wherein said noise sensor is positioned on an inner surface or outer surface of the refrigeration appliance or said noise sensor is positioned on said electrical component.

13. The refrigeration appliance according to claim 12, wherein said noise sensor is positioned on an inner surface of the refrigeration appliance and said noise sensor comprises a temperature detection element for detecting a temperature within a cooling region of the refrigeration appliance.

14. The refrigeration appliance according to claim 1, wherein said controller includes a memory for storing the noise-reduced operating power and said controller is configured to operate said electrical component with the stored noise-reduced operating power.

15. A method for reducing noise in a refrigeration appliance, the refrigeration appliance having an electrical component that emits noise during operation, the method comprising: detecting with a noise sensor a noise intensity of noise emitted by the electrical component; the electrical component having a normal operating range and a maximum operating power within the normal operating power range; operating the electrical component with a controller in the normal operating power range; changing with the controller an operating power of the electrical component within the normal operating power range, in order to determine a plurality of minima for the noise intensity detected by the noise sensor within the normal operating power range; determining with the controller a noise-reduced operating power based on the minimum for the noise intensity that corresponds to an operating power of the electrical component that lies within a tolerance range of the maximum operating power; and operating the electrical component with the controller at the noise-reduced operating power.

16. The method according to claim 15, which comprises changing the operating power of the electrical component and determining the noise-reduced operating power with the controller during a first time segment and operating the electrical component with the noise-reduced operating power by the controller during a second time segment following the first time segment.

17. A refrigeration appliance, comprising: an electrical component, which emits noise during operation; a noise sensor for detecting a noise intensity of the noise emitted by said electrical component; a controller for operating said electrical component in a normal operating power range, said controller being configured to change an operating power of said electrical component within the normal operating power range, to determine a minimum for the noise intensity detected by said noise sensor and to determine a noise-reduced operating power and to operate said electrical component with the noise-reduced operating power; wherein: said controller is configured to change the operating power of said electrical component within the normal operating power range and to determine the minimum for the detected noise intensity and to determine the noise-reduced operating power during a first time segment; said controller is configured to operate said electrical component with the noise-reduced operating power during a second time segment following the first time segment; said controller is configured to determine the noise-reduced operating power after the refrigeration appliance has been connected to an electrical power supply, or said controller is configured to determine the noise-reduced operating power after periodically repeated operating time intervals; and said controller is configured to repeat the first time segment, if said controller fails to determine any change in the noise-reduced operating power during the first time segment and said controller is configured to extend a duration of the periodically repeated operating time intervals if said controller fails to determine any change in noise-reduced operating power after the two successive first time segments.

Description

BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWING

(1) Further exemplary embodiments are described with reference to the accompanying drawings, in which:

(2) FIG. 1 shows a schematic diagram of a refrigeration appliance;

(3) FIG. 2 shows a schematic diagram of a refrigeration appliance with noise sensors;

(4) FIG. 3 shows a schematic diagram of the determination of a noise-reduced operating power of an electrical component within a refrigeration appliance; and

(5) FIG. 4 shows a schematic diagram of a method for reducing noise in a refrigeration appliance.

DESCRIPTION OF THE INVENTION

(6) FIG. 1 shows a refrigerator representing a general refrigeration appliance 100, with a refrigeration appliance door 101 and with an appliance outer wall 103. The refrigeration appliance door 101 is configured to close off a cooling region 105 of the refrigeration appliance 100.

(7) The refrigeration appliance 100 comprises one or more refrigerant circuits, each with a refrigerant evaporator, refrigerant compressor, refrigerant condenser and throttle device. The refrigerant evaporator is a heat exchanger, in which the liquid refrigerant expands before absorbing heat from the cooling medium, e.g. air, which causes it to evaporate. The refrigerant compressor is a mechanically operated component, which takes in refrigerant vapor from the refrigerant evaporator and ejects it to the refrigerant condenser at a higher pressure. The refrigerant condenser is a heat exchanger, in which the evaporated refrigerant is compressed before emitting heat to an external cooling medium, e.g. air, causing it to condense. The refrigeration appliance 100 comprises a ventilator, which is configured to supply a flow of air to the refrigerant condenser and the refrigerant evaporator. The flow of air ensures an effective supply of heat to the refrigerant evaporator. The throttle device is an apparatus for constantly reducing pressure by narrowing the cross section. The refrigerant is a fluid, which is used to transmit heat in the refrigerant circuit, which absorbs heat when the fluid is at low temperature and low pressure and emits heat when the fluid is at higher temperature and higher pressure, generally including changes of state of the fluid.

(8) FIG. 2 shows a schematic diagram of a refrigeration appliance with noise sensors. Arranged in the inventive refrigeration appliance 100 are a first electrical component 107-1 and a second electrical component 107-2. The refrigeration appliance 100 also comprises a first noise sensor 109-1 for detecting an intensity of noise emitted by the first electrical component 107-1 and a second noise sensor 109-2 for detecting an intensity of noise emitted by the second electrical component 107-2. Also arranged in the refrigeration appliance 100 is a controller 111, which is connected to the first electrical component 107-1 by a first appliance line 113, to the second electrical component 107-2 by a second appliance line 115, to the first noise sensor 109-1 by a first sensor line 117 and to the second noise sensor 109-2 by a second sensor line 119.

(9) The refrigeration appliance 100 comprises a plurality of electrical components 107-1, 107-2, which are controlled for example by an electric motor and comprise movable elements, which generate noise, which can in turn be perceived as unpleasant by a user of the refrigeration appliance 100. For example the electrical components 107-1, 107-2 can comprise a refrigerant compressor of a refrigerant circuit of the refrigeration appliance 100, a fan for ventilating a refrigerant condenser of the refrigerant circuit, or flaps or valves of the refrigeration appliance 100.

(10) Structure-borne sound insulation used in conventional refrigeration appliances 100 for the electrical components 107-1, 107-2 can often not be adequate for functional reasons relating to the refrigeration appliance 100, for example because it might restrict cooling capacity, and/or for space and cost reasons.

(11) If the movement of the electrical components 107-1, 107-2 produces structural resonance in the refrigeration appliance 100, the sound emitted is particularly loud. Structural resonance is a function of the size and shape of the refrigeration appliance 100, the way in which the electrical components 107-1, 107-2 are fastened, and the materials used. Even small deviations in fastening, for example sequence of screws or slight tilting of a component against the refrigeration appliance 100, can have a major impact on the frequency range and intensity of excitation of structural resonance.

(12) The scattering of the configuration of the electrical components 107-1, 107-2 can be very wide, with the result that structural resonance is frequently excited in the appliance, often resulting in wide scattering of the noise emitted by the refrigeration appliances 100.

(13) The noise sensors 109-1, 109-2 can be arranged directly on the electrical components 107-1, 107-2, in proximity to them or far away from them. The noise sensors 109-1, 109-2 can be located inside and outside the refrigeration appliance 100. Standard positions are located on an inner surface of the refrigeration appliance 100 or an outer surface of the refrigeration appliance 100. The positioning of the noise sensors 109-1, 109-2 on the appliance wall 103 of the refrigeration appliance 100 is advantageous in that the surface vibration can be identified and used and therefore simple, cost-effective sensors, such as piezo vibration sensors for example, can be used.

(14) Multifunction noise sensors 109-1, 109-2 can also be used, for example those that measure temperature and air-borne sound at the same time. This allows a number of functions of electrical components 107-1, 107-2 to be regulated simultaneously. In principle the noise sensors 109-1, 109-2 must be positioned at points which allow noise emitted by the electrical components 107-1, 107-2 to be calculated from the measurement signal from the noise sensors 109-1, 109-2. This must be ensured in respect of size, configuration and materials for every type of refrigeration appliance 100 in a refrigeration appliance series.

(15) During a standard test of the noise intensity of the electrical components 107-1, 107-2 the electrical components 107-1, 107-2 are actuated individually by the controller 111 and the operating power of the electrical components 107-1, 107-2, e.g. the speed of a fan, is changed within a normal operating power range of the electrical components 107-1, 107-2. The controller 111 uses the measurement signals from the corresponding noise sensors 109-1, 109-2 to determine a minimum for the noise intensity detected by the noise sensor 109-1, 109-2 and a noise-reduced operating power of the electrical components 107-1, 107-2 assigned to the minimum within the normal operating power range. Determination of the noise-reduced operating power can be performed during a first time segment.

(16) Determination of the noise-reduced operating power by the controller 111 allows the electrical components 107-1, 107-2 to be advantageously operated with the noise-reduced operating power during a second time segment following the first time segment and the noise emitted by the electrical components 107-1, 107-2 to be advantageously reduced.

(17) The first time segment for determining the noise-reduced operating power can be performed by the controller 111 regularly during operation of the refrigeration appliance 100 by the user, in order to compensate for example for changes due for example to transportation of the refrigeration appliance 100. If there is no change after two successive first time segments, the time segments between the test intervals can be extended.

(18) The inventive controller 111 allows refrigeration appliances 100 to be operated with less noise and reducing the noise from the electrical components 107-1, 107-2 means that users accept refrigeration appliances 100 more readily. Also refrigeration appliances 100 can be produced more economically as there is no need for additional noise-reducing measures. Also refrigeration appliances 100 can be configured more advantageously, as there is no need for extra noise-reducing measures. Refrigeration appliances 100 therefore operate in the acoustic optimum, as there is continuous and regular optimization of noise intensity.

(19) FIG. 3 shows a schematic diagram of the determination of a noise-reduced operating power of an electrical component within a refrigeration appliance. FIG. 3 shows a diagram over time of the noise intensities of electrical components 107-1, 107-2, shown along the y-axis 121, as a function of operating power, which is shown along the x-axis 123.

(20) The first curve 125 shows the intensity of noise from a first fan of the refrigeration appliance 100 as a function of the motor speed of the fan. The second curve 127 shows the intensity of noise from a second fan of the refrigeration appliance 100 as a function of the motor speed of the second fan. The third curve 129 shows the intensity of noise from a third fan of the refrigeration appliance 100 as a function of the motor speed of the third fan.

(21) It can be seen in FIG. 3 that slight fluctuations in the motor speed of different electrical components 107-1, 107-2 can produce very different noise intensities. Slightly different geometries of the first, second and third fans, which originate from different production batches, mean that there is also a different noise intensity profile as a function of fan motor speed for the first fan, the second fan and the third fan.

(22) In the present instance the operating power, in this instance the motor speed, of the electrical components 107-1, 107-2, in this instance the fans of the refrigeration appliance 100, were changed within the normal operating power range 131 of the electrical components 107-1, 107-2 during a first time segment. In this instance the normal operating power range 131 corresponds to a motor speed range between 1500 rpm and 1650 rpm and is sufficient to ensure effective operation of the fan. The normal operating power range 131 here has a lower operating power point 133 and an upper operating power point 135. The lower and upper operating power points 133, 135 therefore delimit the normal operating power range 131.

(23) The controller 111 determines a minimum 137 for the noise intensity detected by the noise sensors 109-1, 109-2 and determines a noise-reduced operating power 139, which is assigned to the minimum 137. In the present instance there is only a small difference in motor speed between the minimum 137 and a maximum 141 for the detected noise intensity. Nevertheless there is a large acoustic fluctuation between the minimum 137 and maximum 141 for the detected noise intensity.

(24) The advantageous determination of the noise-reduced operating power 139 during the first time segment allows the controller 111 to ensure operation of the electrical components 107-1, 107-2 with the noise-reduced operating power 139 during a second time segment following the first time segment.

(25) FIG. 4 shows a schematic diagram of a method for reducing noise in a refrigeration appliance. The method 200 comprises the following method steps: the controller 111 changing 201 an operating power of the electrical component 107-1, 107-2 within the normal operating power range 131, in order to determine a minimum 137 for the noise intensity detected by the noise sensor 109-1, 109-2; the controller 111 determining 203 the noise-reduced operating power 139 based on the determined minimum 137 and the controller 111 operating 205 the electrical component 107-1, 107-2 with the noise-reduced operating power 139.

(26) All the features described and illustrated in conjunction with individual embodiments of the invention can be provided in different combinations in the inventive subject matter, in order to bring about their advantageous effects simultaneously.

(27) The scope of protection of the present invention is defined by the claims and is not limited by the features described in the description or illustrated in the figures.

LIST OF REFERENCE CHARACTERS

(28) 100 Refrigeration appliance 101 Refrigeration appliance door 103 Appliance outer wall 105 Cooling region 107 Electrical component 107-1 First electrical component 107-2 Second electrical component 109-1 First noise sensor 109-2 Second noise sensor 111 Controller 113 First appliance line 115 Second appliance line 117 First sensor line 119 Second sensor line 121 y-axis 123 x-axis 125 First curve 127 Second curve 129 Third curve 131 Normal operating power range 133 Lower operating power point 135 Upper operating power point 137 Minimum for the detected noise intensity 139 Noise-reduced operating power 141 Maximum for the detected noise intensity 200 Method for reducing noise in a refrigeration appliance 201 Changing an operating power of the electrical component, in order to determine a minimum for the noise intensity detected by the noise sensor 203 Determining the noise-reduced operating power based on the determined minimum 205 Operating the electrical component with noise-reduced operating power