Heater detection device, circuit board and washing machine

Abstract

The utility model relates to the field of washing machines and discloses a heater detection device, a circuit board and a washing machine. The heater detection device comprises a relay, a detection resistor, a live wire, a zero wire, an output circuit and a processing unit. The live wire is electrically connected to the output of a washing machine door lock and electrically connected with the first end of the heater and the first end of the detection resistor, and the detection resistor is connected with the heater in parallel; the first end of the relay is electrically connected with the zero line, the second end of the relay is electrically connected with the second end of the detection resistor and the output circuit, the control end of the relay is electrically connected with the processing unit, and the relay is closed or opened according to a control signal of the processing unit; the output circuit is electrically connected with the processing unit and outputs a detection pulse signal to the processing unit; the processing unit judges the state of the heater according to the detection pulse signal. Therefore, the heater detection device is simple in detection and judgment, simple in circuit structure, low in cost and high in stability, and the detection reliability is improved.

Description

Technical Field

[0001] The utility model relates to the technical field of washing machines, in particular to a heater detection device, a circuit board and a washing machine. Background Art

[0002] At present, with the development of technology, washing machines have more and more functions, and the heating function of washing machines is one of them. The heating function of the washing machine is achieved through a heater. The heater can heat the water entering the washing machine according to the control logic of the processor, so that the water temperature reaches the set temperature to meet the washing needs. In this process, the processor can detect the status of the heater at any time (for example, whether the heater is damaged, etc.) to ensure that the heater is heated according to the control logic of the processor. However, when the processor cannot detect whether the heater is damaged, the heater cannot be heated according to the normal control logic of the processor, resulting in the inability to meet the washing needs, which may cause user complaints due to the inability to wash clean, affecting the user experience. Utility Model Content

[0003] The embodiments of the utility model aim to provide a heater detection device, a circuit board and a washing machine, which can solve the problem that the existing processor cannot detect the state of the washing machine heater, resulting in the heater being unable to heat according to the normal control logic of the processor and unable to meet the washing needs.

[0004] In order to solve the above technical problems, the first embodiment of the utility model provides a heater detection device, which is used to detect the heater of a washing machine. The heater detection device includes a relay, a detection resistor, a live wire, a neutral wire, an output circuit and a processing unit; wherein:

[0005] The live wire is electrically connected to the output of the washing machine door lock. When the heater is connected, the live wire is electrically connected to the first end of the heater and the first end of the detection resistor respectively, and the detection resistor is connected in parallel with the heater;

[0006] The first end of the relay is electrically connected to the neutral line, the second end of the relay is electrically connected to the second end of the detection resistor and the output circuit respectively, and the control end of the relay is electrically connected to the processing unit, and is used to be attracted or disconnected according to the control signal output by the processing unit;

[0007] The output circuit is electrically connected to the processing unit and outputs a detection pulse signal to the processing unit;

[0008] The processing unit is used to determine the state of the heater according to the detection pulse signal output by the output circuit.

[0009] Optionally, the heater detection device further includes a voltage-reducing element, a first end of the voltage-reducing element is electrically connected to the second end of the relay, and a second end of the voltage-reducing element is electrically connected to the output circuit.

[0010] Optionally, the output circuit includes a bidirectional diode, a third resistor and a fourth resistor;

[0011] The second end of the bidirectional diode is electrically connected to the reference voltage end, the third end of the bidirectional diode is electrically connected to the second end of the voltage-reducing element, and the first end of the bidirectional diode is grounded;

[0012] The first end of the third resistor is electrically connected to the second end of the voltage-dropping element, and the second end of the third resistor is electrically connected to the processing unit, outputting a detection pulse signal to the processing unit;

[0013] A first end of the fourth resistor is electrically connected to the reference voltage end, and a second end of the fourth resistor is electrically connected to the second end of the third resistor.

[0014] Optionally, the output circuit further includes a first capacitor, a first end of the first capacitor is electrically connected to the reference voltage end, and a second end of the first capacitor is electrically connected to the second end of the voltage-reducing element.

[0015] Optionally, the output circuit further includes a second capacitor, a first end of the second capacitor is electrically connected to the second end of the third resistor and the second end of the fourth resistor respectively, and a second end of the second capacitor is grounded.

[0016] Optionally, the heater detection device further includes a protector, a first end of the protector is electrically connected to the live wire, and a second end of the protector is electrically connected to the first end of the heater.

[0017] Optionally, the heater detection device further comprises a fuse, a first end of the fuse is electrically connected to the second end of the heater, and a second end of the fuse is electrically connected to the second end of the relay.

[0018] Correspondingly, the second aspect of the present invention provides a circuit board, which includes the heater detection device described in the first aspect of the present invention.

[0019] Correspondingly, the third aspect of the present invention provides a washing machine, comprising the heater detection device and a heater according to the first aspect of the present invention, wherein the heater detection device is electrically connected to the heater for detecting the state of the heater.

[0020] Correspondingly, the fourth aspect of the present invention provides a washing machine, comprising the circuit board and the heater described in the third aspect of the present invention, wherein the circuit board is electrically connected to the heater for detecting the state of the heater.

[0021] Compared with the prior art, the utility model provides a heater detection device, a circuit board and a washing machine. The heater detection device is used to detect the heater of the washing machine, and includes a relay, a detection resistor, a live wire, a neutral wire, an output circuit and a processing unit; wherein: the live wire is electrically connected to the output of the washing machine door lock, and when the heater is connected, the live wire is electrically connected to the first end of the heater and the first end of the detection resistor respectively, and the detection resistor is connected in parallel with the heater; the first end of the relay is electrically connected to the neutral wire, the second end of the relay is electrically connected to the second end of the detection resistor and the output circuit respectively, and the control end of the relay is electrically connected to the processing unit, and is used to be attracted or disconnected according to the control signal output by the processing unit; the output circuit is electrically connected to the processing unit, and outputs a detection pulse signal to the processing unit; the processing unit judges the state of the heater according to the detection pulse signal output by the output circuit. Thus, the detection principle of the heater detection device is simple, and the judgment is convenient and simple. The detection device uses a resistor as the main component, the circuit structure is simple, the cost is low, the resistor is relatively stable under different temperature conditions, the stability is high, and the reliability of the detection is improved, so that the heater can be heated according to the normal control logic of the processing unit to meet the washing needs. This can solve the problem that the existing processor cannot detect the state of the washing machine heater, causing the heater to be unable to heat according to the normal control logic of the processor and unable to meet the washing demand. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] One or more embodiments are exemplarily described by pictures in the corresponding drawings, and these exemplified descriptions do not constitute limitations on the embodiments. Elements with the same reference numerals in the drawings represent similar elements, and unless otherwise stated, the figures in the drawings do not constitute proportional limitations.

[0023] Figure 1 It is a structural schematic diagram of a heater detection device provided by the utility model;

[0024] Figure 2 It is another structural schematic diagram of a heater detection device provided by the utility model;

[0025] Figure 3 It is a circuit diagram of a heater detection device provided by the utility model;

[0026] Figure 4 It is a schematic diagram of a heater detection device provided by the utility model detecting a pulse signal when a relay is disconnected or a heater is in an abnormal state;

[0027] Figure 5 It is a schematic diagram of a heater detection device provided by the utility model detecting a pulse signal when a relay is energized;

[0028] Figure 6 It is a structural schematic diagram of a circuit board provided by the utility model;

[0029] Figure 7 It is a structural schematic diagram of a washing machine provided by the utility model;

[0030] Figure 8 It is another structural schematic diagram of a washing machine provided by the utility model.

[0031] Description of main component symbols:

[0032] Heater detection circuit 1 Heater T1

[0033] Detection resistor R1 Voltage drop element R2

[0034] Relay RL1 Output circuit S1

[0035] Processing unit U1 Protector B1

[0036] Fuse F1 First capacitor C1

[0037] The second capacitor C2 and the third resistor R3

[0038] Fourth resistor R4 Circuit board 10

[0039] Washing Machine 100 DETAILED DESCRIPTION

[0040] In order to facilitate the understanding of the utility model, the utility model is described in more detail below in conjunction with the accompanying drawings and specific embodiments. It should be noted that when an element is described as "fixed to" another element, it can be directly on another element, or there can be one or more centered elements therebetween. When an element is described as "connected" to another element, it can be directly connected to another element, or there can be one or more centered elements therebetween. The orientation or positional relationship indicated by the terms "upper", "lower", "inner", "outer", "bottom" and the like used in this specification is based on the orientation or positional relationship shown in the accompanying drawings, only for the convenience of describing the utility model and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the utility model. In addition, the terms "first", "second", "third" and the like are only used for descriptive purposes and cannot be understood as indicating or implying relative importance.

[0041] Unless otherwise defined, all technical and scientific terms used in this specification have the same meaning as those commonly understood by technicians in the technical field of the present invention. The terms used in this specification are only for the purpose of describing specific embodiments and are not used to limit the present invention. The term "and / or" used in this specification includes any and all combinations of one or more related listed items.

[0042] In addition, the technical features involved in different embodiments of the present invention described below can be combined with each other as long as they do not conflict with each other.

[0043] In one embodiment, Figure 1 As shown, the utility model provides a heater detection device 1, which is used to detect a washing machine heater T1. The heater detection device 1 includes: a relay RL1, a detection resistor R1, a live wire L, a neutral wire N, an output circuit S1 and a processing unit U1; wherein:

[0044] The live wire L is electrically connected to the output of the washing machine door lock. When the heater T1 is connected, the live wire L is electrically connected to the first end of the heater T1 and the first end of the detection resistor R1 respectively, and the detection resistor R1 is connected in parallel with the heater T1;

[0045] The first end of the relay RL1 is electrically connected to the neutral line N, the second end of the relay RL1 is electrically connected to the second end of the detection resistor R1 and the output circuit S1 respectively, and the control end of the relay RL1 is electrically connected to the processing unit U1, and is used to be attracted or disconnected according to the control signal output by the processing unit U1;

[0046] The output circuit S1 is electrically connected to the processing unit U1 and outputs a detection pulse signal to the processing unit;

[0047] The processing unit U1 is used to determine the state of the heater according to the detection pulse signal output by the output circuit S1.

[0048] In this embodiment, a heater detection device is provided, which is applied to detect the heater of a washing machine, and includes a relay, a detection resistor, a live wire, a neutral wire, an output circuit and a processing unit; wherein: the live wire is electrically connected to the output of the door lock of the washing machine, and when the heater is connected, the live wire is electrically connected to the first end of the heater and the first end of the detection resistor respectively, and the detection resistor is connected in parallel with the heater; the first end of the relay is electrically connected to the neutral wire, the second end of the relay is electrically connected to the second end of the detection resistor and the output circuit respectively, and the control end of the relay is electrically connected to the processing unit, and is used to be attracted or disconnected according to the control signal output by the processing unit; the output circuit is electrically connected to the processing unit, and outputs a detection pulse signal to the processing unit; the processing unit judges the state of the heater according to the detection pulse signal output by the output circuit. Thus, the detection principle of the heater detection device is simple, the judgment is convenient and simple, and the detection device uses a resistor as the main component, the circuit structure is simple, the cost is low, the resistor is relatively stable under different temperature conditions, the stability is high, and the reliability of the detection is improved, so that the heater can be heated according to the normal control logic of the processing unit to meet the washing needs. This can solve the problem that the existing processor cannot detect the state of the washing machine heater, causing the heater to be unable to heat according to the normal control logic of the processor and unable to meet the washing demand.

[0049] In one embodiment, Figures 1 to 3 As shown, the first end of the detection resistor R1 is electrically connected to the first end of the heater T1, the second end of the detection resistor R1 is electrically connected to the second end of the heater T1, and the detection resistor R1 and the heater T1 are in parallel; the live wire L is electrically connected to the first end of the heater T1 and the first end of the detection resistor R1, respectively.

[0050] Specifically, the live wire L is electrically connected to the output of the washing machine door lock. When the washing machine is powered on, the washing machine door lock is locked, the relay RL1 is energized under the control signal output by the processing unit U1, the live wire L and the neutral wire N are loaded on the heater T1, and the heater T1 is connected to the heater detection device 1. At this time, the live wire L is electrically connected to the first end of the heater T1, and at the same time, the live wire L is also electrically connected to the first end of the detection resistor R1; the second end of the detection resistor R1 is electrically connected to the second end of the heater T1, so that the detection resistor R1 and the heater T1 are in parallel.

[0051] Among them, the resistance value of the detection resistor R1 is relatively large, for example, the resistance value of the detection resistor R1 is 100K ohm level. In this way, when the detection resistor R1 and the heater T1 are in parallel state, and the state of the heater T1 is normal (i.e., not damaged), the current output in the parallel state is relatively large, so that the current reaching the output circuit S1 is also relatively large. After passing through the output circuit S1, the output circuit S1 outputs a detection pulse signal with a relatively high voltage, so that the processing unit 2 can determine that the state of the heater T1 is normal, so that the heater T1 can be heated according to the normal control logic of the processing unit to meet the washing requirements. However, when the state of the heater T1 is abnormal (i.e., damaged), the detection resistor R1 is not in parallel with the heater T1, and the current output in the non-parallel state is smaller, so that the current reaching the output circuit S1 is also correspondingly smaller. After passing through the output circuit S1, the output circuit S1 outputs a detection pulse signal with a lower voltage, so that the processing unit 2 can determine that the state of the heater T1 is abnormal, so that the heater T1 cannot be heated according to the normal control logic of the processing unit, and cannot meet the washing requirements.

[0052] Therefore, by detecting the current flowing through the detection resistor R1 and the heater T1 in parallel, and then detecting the voltage of the output circuit, the processing unit can determine the state of the heater T1 and whether the heater T1 is damaged. When the output circuit voltage is detected to be low, it can be determined that the state of the heater T1 is normal and the heater T1 is not damaged; when the output circuit voltage is detected to be high, it can be determined that the state of the heater T1 is abnormal and the heater T1 is damaged. This makes the detection principle of the heater detection device simple, and the judgment is convenient and simple.

[0053] In one embodiment, Figure 2 and Figure 3 As shown, the heater detection device 1 further includes a voltage reducing element R2, a first end of the voltage reducing element R2 is electrically connected to the second end of the relay RL1, and a second end of the voltage reducing element R2 is electrically connected to the output circuit S1, for reducing the voltage from the live wire L.

[0054] For example, Figure 3 As shown, the voltage-dropping element R2 is a voltage-dropping resistor, and the resistance value of the voltage-dropping resistor is relatively large. For example, the resistance value of the voltage-dropping resistor is at the level of 100K ohms.

[0055] In one embodiment, Figures 1 to 3 As shown, the output circuit S1 is electrically connected to the second end of the detection resistor R1, the second end of the relay RL1 and the processing unit U1 respectively, and the output circuit is used to output a detection pulse signal to the processing unit.

[0056] Specifically, the output circuit S1 outputs the detection pulse signal Heat_FB to the processing unit U1 for processing according to the current in the parallel state of the detection resistor R1 and the heater T1, so that the processing unit U1 determines the state of the heater according to the detection pulse signal Heat_FB.

[0057] like Figure 2 As shown, the output circuit S1 is electrically connected to the second end of the relay RL1 through the voltage-reducing element R2 , and the output circuit S1 is electrically connected to the processing unit U1 .

[0058] like Figure 3 As shown, the output circuit includes: a bidirectional diode D1, a first capacitor C1, a second capacitor C2, a third resistor R3 and a fourth resistor R4.

[0059] The first end of the first capacitor C1 is electrically connected to the reference voltage end, and the second end of the first capacitor C1 is electrically connected to the second end of the voltage-reducing element R2. The first capacitor C1 is a filter capacitor, which is used to filter the noise generated on the reference voltage of the reference voltage end when the reference voltage of the reference voltage end is interfered by external interference (for example, interference or discharge by electrostatic discharge (ESD)). For example, the reference voltage of the reference voltage end is +5V.

[0060] The second end of the bidirectional diode D1 is electrically connected to the reference voltage end, the third end of the bidirectional diode D1 is electrically connected to the second end of the voltage-reducing element R2, and the first end of the bidirectional diode D1 is grounded. The bidirectional diode D1 acts as a clamp to prevent the signal line from being easily disturbed by ESD or discharge from damaging the output circuit, thereby achieving the purpose of ESD protection. For example, the bidirectional diode D1 is a BAV99 diode.

[0061] The first end of the third resistor R3 is electrically connected to the second end of the voltage-reducing element R2 , and the second end of the third resistor R3 is electrically connected to the processing unit U1 , and outputs the detection pulse signal Heat_FB to the processing unit U1 .

[0062] The first end of the fourth resistor R4 is electrically connected to the reference voltage end, the second end of the fourth resistor R4 is electrically connected to the second end of the third resistor R3, and the second end of the fourth resistor R4 is grounded through the second capacitor C2. The fourth resistor is a voltage dividing resistor, which divides the reference voltage of the reference voltage end.

[0063] The first end of the second capacitor C2 is electrically connected to the second end of the third resistor R3 and the second end of the fourth resistor R4, respectively, and the second end of the second capacitor C2 is grounded. The second capacitor C2 is a filter capacitor, which is used to filter the noise generated by the ground terminal when the ground terminal is subject to external interference (for example, interference or discharge of electrostatic discharge).

[0064] In one embodiment, Figures 1 to 3 As shown, the processing unit U1 is electrically connected to the output circuit S1 and is used to determine the state of the heater according to the detection pulse signal output by the output circuit S1.

[0065] Specifically, the processing unit U1 uses the detection pulse signal output by the output circuit S1 to determine the state of the heater, including: when the detection pulse signal Heat_FB is a lower voltage, it can be determined that the state of the heater T1 is normal and the heater T1 is not damaged; when the output circuit voltage is detected to be higher, it can be determined that the state of the heater T1 is abnormal and the heater T1 is damaged.

[0066] The processing unit U1 has data processing capabilities and signal processing capabilities, and can be an integrated circuit chip. For example, the processing unit U1 can be a general-purpose processor, DSP (Digital Signal Processor), FPGA (Field Programmable Gate Array) or other programmable logic devices, etc. The general-purpose processor can be a microprocessor, MCU (Microcontroller Unit) or any conventional processor, etc.

[0067] In one embodiment, Figure 2 and Figure 3 As shown, the heater detection device 1 also includes a protector B1, a first end of the protector B1 is electrically connected to the live wire L, and a second end of the protector B1 is electrically connected to the first end of the heater T1. The protector is used to protect the heater T1 from being damaged due to excessive voltage when the heater T1 is connected to the heater detection device.

[0068] In one embodiment, Figure 2 and Figure 3 As shown, the heater detection device 1 also includes a fuse F1, a first end of the fuse F1 is electrically connected to the second end of the heater T1, and a second end of the fuse F1 is electrically connected to the second end of the relay RL1. The fuse is used to automatically blow when the current flowing through the heater T1 exceeds a current threshold when the heater T1 is connected to the heater detection device, so as to avoid damage to the heater T1 due to excessive current.

[0069] The utility model provides a heater detection device 1, which is used to detect a washing machine heater T1. When working, the detection principle is as follows:

[0070] (1) When the washing machine is powered on and the door lock is unlocked, since the live wire L is electrically connected to the output of the door lock, no AC current passes through the live wire L, and the detection pulse signal Heat_FB reaches the reference voltage +5V of the reference voltage terminal through the fourth resistor R4.

[0071] (2) When the washing machine is powered on and the door is locked, AC current flows through the live wire L. When the relay RL1 is not energized, the voltage of the live wire L passes through the detection resistor R1 and the large resistance of the voltage-reducing element R2, and the voltage reaching the third resistor R3 of the output circuit S1 is low, close to 0V. The waveform of the detection pulse signal Heat_FB output by the output circuit S1 is as follows: Figure 4 As shown, the low level of the waveform is close to 0V, the high level is close to 5V, and the signal frequency is consistent with the input AC power frequency.

[0072] (3) When the washing machine is powered on and the door is locked, AC current passes through the live wire L. When the relay RL1 is energized by the control signal output by the processing unit U1, the live wire L and the neutral wire N are loaded onto the heater T1, and the heater T1 is connected to the heater detection device 1.

[0073] When the heater T1 is in a normal state, the waveform of the detection pulse signal Heat_FB output by the output circuit S1 is as follows: Figure 5 As shown, the low level of the waveform is close to 2.5V, the high level is close to 5V, and the signal frequency is consistent with the input AC power frequency.

[0074] When the heater T1 is in an abnormal state, the waveform of the detection pulse signal Heat_FB output by the output circuit S1 is as follows: Figure 4 As shown, the low level of the waveform is close to 0V, the high level is close to 5V, and the signal frequency is consistent with the input AC power frequency.

[0075] The processing unit U1 can determine the state of the heater T1 and whether the heater T1 is damaged according to the waveform of the detection pulse signal Heat_FB output by the output circuit S1. When the voltage detection pulse signal Heat_FB of the output circuit is detected to be between 2.5V and 5V, it can be determined that the state of the heater T1 is normal and the heater T1 is not damaged; when the voltage detection pulse signal Heat_FB of the output circuit is detected to be between 0V and 5V, it can be determined that the state of the heater T1 is abnormal and the heater T1 is damaged. This makes the detection principle of the heater detection device simple, and the judgment is convenient and simple.

[0076] Based on the same concept, in one embodiment, Figure 6 As shown, an embodiment of the utility model further provides a circuit board 10, and the circuit board 10 includes the heater detection device 1 described in any of the above embodiments.

[0077] In this embodiment, the heater detection device 1 is consistent with the heater detection device 1 described in any of the above embodiments. The specific structure and function can refer to the heater detection device 1 described in any of the above embodiments, and will not be repeated here.

[0078] The circuit board 10 can be one piece or a plurality of pieces spliced ​​together.

[0079] In this embodiment, a circuit board is provided, including a heater detection device, which is used to detect the heater of a washing machine, including a relay, a detection resistor, a live wire, a neutral wire, an output circuit and a processing unit; wherein: the live wire is electrically connected to the output of the washing machine door lock, and when the heater is connected, the live wire is electrically connected to the first end of the heater and the first end of the detection resistor respectively, and the detection resistor is connected in parallel with the heater; the first end of the relay is electrically connected to the neutral wire, the second end of the relay is electrically connected to the second end of the detection resistor and the output circuit respectively, and the control end of the relay is electrically connected to the processing unit, and is used to be attracted or disconnected according to the control signal output by the processing unit; the output circuit is electrically connected to the processing unit, and outputs a detection pulse signal to the processing unit; the processing unit judges the state of the heater according to the detection pulse signal output by the output circuit. Thus, the detection principle of the heater detection device is simple, the judgment is convenient and simple, and the detection device uses a resistor as the main component, the circuit structure is simple, the cost is low, the resistor is relatively stable under different temperature conditions, the stability is high, and the reliability of the detection is improved, so that the heater can be heated according to the normal control logic of the processing unit to meet the washing needs. This can solve the problem that the existing processor cannot detect the state of the washing machine heater, causing the heater to be unable to heat according to the normal control logic of the processor and unable to meet the washing demand.

[0080] It should be noted that the above-mentioned washing machine embodiment and the heater detection device embodiment belong to the same concept, and the specific implementation process is detailed in the heater detection device embodiment, and the technical features in the heater detection device embodiment are correspondingly applicable in the above-mentioned washing machine embodiment, which will not be repeated here.

[0081] Based on the same concept, in one embodiment, Figure 7 and Figure 8As shown, the embodiment of the utility model further provides a washing machine, the washing machine 100 comprises the heater detection device 1 and the heater T1 as described in any of the above embodiments, the heater detection device 1 is electrically connected to the heater T1, and is used to detect the state of the heater T1.

[0082] Alternatively, the washing machine 100 includes the circuit board 10 and the heater T1 described in any of the above embodiments, and the circuit board 10 is electrically connected to the heater T1 for detecting the state of the heater T1.

[0083] In this embodiment, the heater detection device 1 is consistent with the heater detection device 1 described in any of the above embodiments. The specific structure and function can refer to the heater detection device 1 described in any of the above embodiments, which will not be repeated here.

[0084] The circuit board 10 is consistent with the circuit board 10 described in any of the above embodiments. The specific structure and function can refer to the circuit board 10 described in any of the above embodiments, and will not be repeated here.

[0085] In this embodiment, a washing machine is provided, comprising a heater detection device and a heater, the heater detection device is electrically connected to the heater and used to detect the state of the heater; or comprising a circuit board and a heater, the circuit board is electrically connected to the heater and used to detect the state of the heater. The circuit board comprises a heater detection device, the heater detection device is used to detect the heater of the washing machine, and comprises a relay, a detection resistor, a live wire, a neutral wire, an output circuit and a processing unit; wherein: the live wire is electrically connected to the output of the washing machine door lock, and when the heater is connected, the live wire is electrically connected to the first end of the heater and the first end of the detection resistor respectively, and the detection resistor is connected in parallel with the heater; the first end of the relay is electrically connected to the neutral wire, the second end of the relay is electrically connected to the second end of the detection resistor and the output circuit respectively, and the control end of the relay is electrically connected to the processing unit, and is used to be attracted or disconnected according to the control signal output by the processing unit; the output circuit is electrically connected to the processing unit, and outputs a detection pulse signal to the processing unit; the processing unit determines the state of the heater according to the detection pulse signal output by the output circuit. As a result, the detection principle of the heater detection device is simple, and the judgment is convenient and simple. The detection device uses resistors as the main components, with a simple circuit structure and low cost. The resistors are relatively stable under different temperature conditions and have high stability, which improves the reliability of detection, so that the heater can be heated according to the normal control logic of the processing unit to meet the washing needs. This can solve the problem that the existing processor cannot detect the state of the washing machine heater, causing the heater to be unable to heat according to the normal control logic of the processor and unable to meet the washing needs. It should be noted that the above-mentioned washing machine embodiment and the heater detection device or circuit board embodiment belong to the same concept, and the specific implementation process is detailed in the heater detection device or circuit board embodiment, and the technical features in the heater detection device or circuit board embodiment are applicable to the above-mentioned washing machine embodiment, which will not be repeated here.

[0086] It should be noted that, in this article, the terms "include", "comprises" or any other variations thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or device. In the absence of further restrictions, an element defined by the sentence "comprises a ..." does not exclude the existence of other identical elements in the process, method, article or device including the element.

[0087] The above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit them. Under the concept of the present invention, the technical features in the above embodiments or different embodiments can also be combined, the steps can be implemented in any order, and there are many other changes in different aspects of the present invention as described above, which are not provided in detail for the sake of simplicity. Although the present invention has been described in detail with reference to the aforementioned embodiments, a person of ordinary skill in the art should understand that the technical solutions described in the aforementioned embodiments can still be modified, or some of the technical features can be replaced by equivalents. These modifications or replacements do not deviate the essence of the corresponding technical solutions from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. A heater detection device, used for detecting a washing machine heater, characterized in that: The heater detection device comprises a relay, a detection resistor, a live wire, a neutral wire, an output circuit and a processing unit; wherein: The live wire is electrically connected to the output of the washing machine door lock. When the heater is connected, the live wire is electrically connected to the first end of the heater and the first end of the detection resistor respectively, and the detection resistor is connected in parallel with the heater; The first end of the relay is electrically connected to the neutral line, the second end of the relay is electrically connected to the second end of the detection resistor and the output circuit respectively, and the control end of the relay is electrically connected to the processing unit, and is used to be attracted or disconnected according to the control signal output by the processing unit; The output circuit is electrically connected to the processing unit and outputs a detection pulse signal to the processing unit; The processing unit is used to determine the state of the heater according to the detection pulse signal output by the output circuit.

2. The heater detection device according to claim 1, characterized in that: The heater detection device further includes a voltage-reducing element, a first end of the voltage-reducing element is electrically connected to a second end of the relay, and a second end of the voltage-reducing element is electrically connected to the output circuit.

3. The heater detection device according to claim 2, characterized in that: The output circuit includes a bidirectional diode, a third resistor and a fourth resistor; The second end of the bidirectional diode is electrically connected to the reference voltage end, the third end of the bidirectional diode is electrically connected to the second end of the voltage-reducing element, and the first end of the bidirectional diode is grounded; The first end of the third resistor is electrically connected to the second end of the voltage-dropping element, and the second end of the third resistor is electrically connected to the processing unit, outputting a detection pulse signal to the processing unit; A first end of the fourth resistor is electrically connected to the reference voltage end, and a second end of the fourth resistor is electrically connected to the second end of the third resistor.

4. The heater detection device according to claim 3, characterized in that: The output circuit further includes a first capacitor, a first end of the first capacitor is electrically connected to the reference voltage end, and a second end of the first capacitor is electrically connected to the second end of the voltage-reducing element.

5. The heater detection device according to claim 3, characterized in that: The output circuit further includes a second capacitor, a first end of the second capacitor is electrically connected to the second end of the third resistor and the second end of the fourth resistor respectively, and a second end of the second capacitor is grounded.

6. The heater detection device according to claim 1, characterized in that: The heater detection device further includes a protector, a first end of the protector being electrically connected to the live wire, and a second end of the protector being electrically connected to the first end of the heater.

7. The heater detection device according to claim 1, characterized in that: The heater detection device further includes a fuse, a first end of the fuse is electrically connected to a second end of the heater, and a second end of the fuse is electrically connected to a second end of the relay.

8. A circuit board, characterized in that: The circuit board includes the heater detection device according to any one of claims 1 to 7.

9. A washing machine, characterized in that: The washing machine comprises the heater detection device according to any one of claims 1 to 7 and a heater, wherein the heater detection device is electrically connected to the heater and is used to detect a state of the heater.

10. A washing machine, characterized in that: The washing machine comprises the circuit board and a heater according to claim 8, wherein the circuit board is electrically connected to the heater and is used to detect a state of the heater.

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