Detection system, household electrical appliance and detection method of household electrical appliance

Abstract

The embodiment of the invention discloses a detection system, a household appliance and a detection method of the household appliance. The system comprises a power supply circuit, a first thermal circuit breaker, a first resistor, a first voltage detection circuit, a power conversion circuit and a control circuit. The power supply circuit comprises a zero line and a live line. The first thermal circuit breaker is connected in series with a zero line or a live line; the first resistor is connected in parallel with the first thermal circuit breaker; the first voltage detection circuit is connected with the output end of a zero line or a live line connected in series with the first thermal circuit breaker; the power conversion circuit is connected with the live wire and the zero line; the control circuit controls the electric load to run for a preset time after being powered on, the first voltage detection circuit obtains a corresponding first voltage detection signal, and the control circuit judges whether the plug has a spark discharge phenomenon or not based on the first voltage detection signal. The system is simple in structure, relatively small in size and relatively high in integration level, and not only can detect the spark discharge phenomenon of the plug, but also can protect the circuit under the spark discharge phenomenon.

Description

Technical Field

[0001] This application relates to the field of household appliance technology, and more particularly to a testing system, a household appliance, and a testing method for a household appliance. Background Technology

[0002] Household appliances are usually equipped with plugs to connect to sockets. However, the metal parts of the plug are prone to aging, which may lead to poor contact when they come into contact with the socket. Poor contact may cause spark discharge (i.e., arcing) in the plug, which poses a certain safety hazard.

[0003] Related technologies typically include additional anti-burn detection equipment to detect spark discharge phenomena in the plug. However, the anti-burn detection equipment in these technologies is complex in design and occupies a large area, making it unsuitable for miniaturization. Summary of the Invention

[0004] This application provides a detection system, a household appliance, and a method for detecting household appliances, aiming to improve the problems of large size and large area occupied by anti-burn detection equipment in related technologies, as well as complex design.

[0005] In a first aspect, embodiments of this application provide a detection system applied to a household appliance. The household appliance includes an electrical load and a plug. The detection system includes a power supply circuit, a first thermal circuit breaker, a first resistor, a first voltage detection circuit, a power conversion circuit, and a control circuit. The power supply circuit includes a neutral wire and a live wire, both of which are connected to the plug and the electrical load. The neutral wire and the live wire are used to supply power to the electrical load. The first thermal circuit breaker is connected in series with either the neutral wire or the live wire. The first resistor is connected in parallel with the first thermal circuit breaker and is also disposed inside the plug. The first voltage detection circuit is connected to the output terminal of the neutral wire or the live wire connected in series with the first thermal circuit breaker. The power conversion circuit is connected to the live wire and the neutral wire. The control circuit is connected to the neutral wire, the first voltage detection circuit, the electrical load, and the power conversion circuit. The control circuit is used to control the electrical load to run for a preset time after power-on. The first voltage detection circuit is used to acquire a corresponding first voltage detection signal and output it to the control circuit. The control circuit is used to determine whether there is a spark discharge phenomenon in the plug based on the first voltage detection signal.

[0006] Based on the detection system provided in this application, when spark discharge occurs in the plug, a large voltage drop is generated across the first resistor, which can promptly shut down the electrical load and control circuit, reducing the risk of damage to the electrical load and control circuit caused by spark discharge, and extending the service life of the electrical load, control circuit, and other circuits on the line. Simultaneously, the first voltage detection circuit can promptly detect voltage fluctuations on the live or neutral wire and generate a corresponding first voltage detection signal to the control circuit. This allows the control voltage to promptly detect the plug's status based on the first voltage detection signal to determine whether spark discharge occurs, resulting in high reliability and accuracy. If spark discharge is detected, it is immediately reported for repair. Secondly, the detection system has a simple circuit, requiring no additional anti-burn detection equipment, resulting in lower cost, smaller size, and smaller footprint. Furthermore, both the first resistor and the first thermal circuit breaker are integrated into the plug, resulting in high integration, suitable for the miniaturization of household appliances. In short, the small-volume, highly integrated detection system provided in this application not only reliably detects spark discharge in the plug but also protects the circuit under spark discharge conditions.

[0007] In some exemplary embodiments, the control circuit has a preset voltage threshold. When the first voltage detection signal is equal to the voltage threshold, the control circuit determines that there is no spark discharge phenomenon in the plug; when the first voltage detection signal is not equal to the voltage threshold, the control circuit determines that there is a spark discharge phenomenon in the plug.

[0008] In the above technical solution, when the first thermal circuit breaker is turned on, the control circuit can obtain the first voltage detection signal of the electrical load during operation through the first voltage detection circuit. If the first thermal circuit breaker is turned off while the electrical load is in operation, there will be a significant difference between the first voltage detection signal collected and output to the control circuit by the first voltage detection circuit and the preset voltage threshold. This makes it easy for the control circuit to distinguish between the first voltage detection signal and the voltage threshold, and thus determine whether there is a spark discharge phenomenon in the plug. In other words, by comparing the first voltage detection signal and the voltage threshold, the control circuit can accurately determine whether there is a spark discharge phenomenon in the plug, resulting in high detection reliability and accuracy.

[0009] In some exemplary embodiments, the household appliance further includes a thermostat connected to the neutral and live wires. The detection system further includes a second thermal circuit breaker, a second resistor, and a second voltage detection circuit. The second thermal circuit breaker is connected in series with the neutral or live wire and is located between the first thermal circuit breaker and the power conversion circuit. The second resistor is connected in parallel with the second thermal circuit breaker and is also located within the thermostat. The second voltage detection circuit is connected to the output terminal of the neutral or live wire connected in series with the second thermal circuit breaker. After the electrical load has been running for a preset period of time, the second voltage detection circuit is used to acquire the corresponding second voltage detection signal and output it to the control circuit. The control circuit is also used to determine whether the thermostat has tripped based on the second voltage detection signal.

[0010] In the above technical solution, the control circuit can detect not only the spark discharge phenomenon of the plug based on the first voltage detection signal, but also the tripping phenomenon of the temperature limiter based on the second voltage detection signal. This means the control system can achieve dual detection, improving detection reliability and accuracy. Secondly, the control circuit detects the spark discharge phenomenon of the plug through the first thermal circuit breaker, the first resistor, and the first voltage detection signal corresponding to the first voltage detection circuit. Simultaneously, it detects the tripping phenomenon of the temperature limiter through the second thermal circuit breaker, the second resistor, and the second voltage detection signal corresponding to the second voltage detection circuit. In other words, the control circuit uses two different voltage detection signals to detect both the plug and the temperature limiter, avoiding the risk of false alarms when using the same voltage detection signal, further improving detection accuracy and reliability.

[0011] In some exemplary embodiments, when the first voltage detection signal is equal to the second voltage detection signal and the voltage threshold, the control circuit determines that there is no spark discharge phenomenon in the plug and the temperature limiter does not trip; when the second voltage detection signal is equal to the first voltage detection signal and the second voltage detection signal is less than the voltage threshold, the control circuit determines that there is a spark discharge phenomenon in the plug and the temperature limiter does not trip; when the second voltage detection signal is less than the first voltage detection signal and the first voltage detection signal is equal to the voltage threshold, the control circuit determines that there is no spark discharge phenomenon in the plug and the temperature limiter trips; when the second voltage detection signal is less than the first voltage detection signal and the first voltage detection signal is less than the voltage threshold, the control circuit determines that there is a spark discharge phenomenon in the plug and the temperature limiter trips.

[0012] In the above technical solution, when the first or second thermal circuit breaker is open and the electrical load is in operation, there is a significant difference between the first voltage detection signal and the second voltage detection signal collected and output to the control circuit by the first and second voltage detection circuits and the preset voltage threshold V. This allows the control circuit 24 to easily distinguish between the first voltage detection signal VD1, the second voltage detection signal VD2, and the voltage threshold V, thereby determining whether there is a spark discharge phenomenon in the plug 12 and whether the temperature limiter 14 has tripped. In other words, by comparing the first voltage detection signal VD1, the second voltage detection signal VD2, and the voltage threshold V, the control circuit 24 can accurately determine whether there is a spark discharge phenomenon in the plug 12 and whether the temperature limiter 14 has tripped. Comparing the three voltage values ​​avoids the risk of false alarms, resulting in high detection reliability and accuracy.

[0013] In some exemplary embodiments, the power conversion circuit includes an AC-DC converter, the input of which is connected to the live wire, and the output of which is connected to the control circuit. The AC-DC converter is used to convert the AC power supplied by the live wire into DC power and output it to the control circuit.

[0014] In the above technical solution, the AC-DC converter can convert the AC power output from the live wire into DC power, so that DC power can be used to power the DC load (i.e., the control circuit), thereby ensuring the reliability of the power supply to the control circuit and thus ensuring the operational reliability of the control circuit.

[0015] In some exemplary embodiments, the power conversion circuit further includes a first rectifier module, a first filter module, and a second filter module; the first rectifier module is connected to the live wire; the first filter module is connected to the first rectifier module, the neutral wire, and the input terminal of the AC-DC converter; the second filter module is connected to the output terminal of the AC-DC converter, the neutral wire, and the control circuit, and is connected to the power supply voltage.

[0016] In the above technical solution, the first rectifier module converts the AC power supplied by the live wire into pulsating DC power, providing a preliminary DC signal for the subsequent first filter module and AC-DC converter. The first filter module significantly reduces the ripple of the voltage output by the first rectifier module, thereby improving the purity of the DC output. Simultaneously, the first filter module also suppresses high-frequency noise, preventing it from entering the AC-DC converter and affecting its operational stability, thus improving the input adaptability and stability of the AC-DC converter, and consequently improving its conversion stability. The second filter module filters the supply voltage generated by the AC-DC converter to improve the purity of the supply voltage output to the control circuit, thereby improving the stability and reliability of the control circuit operating based on this supply voltage.

[0017] In some exemplary embodiments, the first rectifier module includes a first diode, and the first filter module includes a first capacitor, an inductor, and a second capacitor; the positive terminal of the first diode is connected to the live wire, the negative terminal of the first diode is connected to the first plate of the first capacitor and one end of the inductor, the second plate of the first capacitor is connected to the neutral wire, the other end of the inductor is connected to the first plate of the second capacitor and the input terminal of the AC-DC converter, and the second plate of the second capacitor is connected to the neutral wire.

[0018] In the above technical solution, the first diode converts the AC power supplied by the live wire into pulsating DC power, providing a preliminary DC signal for the subsequent first filter module and AC-DC converter. The "π" filter, composed of the first capacitor, inductor, and second capacitor, has the following characteristics: the first capacitor filters out high-frequency ripple; the inductor, connected in series in the main power supply line, prevents high-frequency signals from passing through; and the second capacitor further filters out residual AC components, significantly reducing the voltage ripple of the first rectifier module's output voltage, thereby improving the purity of the DC output. Simultaneously, it suppresses high-frequency noise, preventing it from entering the AC-DC converter and affecting its operational stability, thus improving the input adaptability and stability of the AC-DC converter, and ultimately enhancing its conversion stability.

[0019] In some exemplary embodiments, the first voltage detection circuit includes a voltage divider module and a current limiting module; the first end of the voltage divider module is connected to the output end of the neutral or live wire connected in series with the first thermal circuit breaker, and the second end of the voltage divider module is grounded; one end of the current limiting module is connected to the third end of the voltage divider module, and the other end of the current limiting module is connected to the control circuit.

[0020] In the above technical solution, the voltage divider module can divide the acquired voltage before outputting it to the subsequent circuit (e.g., the control circuit), preventing voltage signals exceeding the rated voltage of the control circuit from entering the control circuit. The current limiting module can limit current signals exceeding the rated current of the control circuit from entering the control circuit, thereby reducing the probability of damage to the control circuit, improving the reliability of the control circuit, and enabling the control circuit to have a longer service life, which in turn enables the detection system to have a longer service life.

[0021] In some exemplary embodiments, the voltage divider module includes a plurality of third resistors connected in series; wherein, the end of the first third resistor that is not connected to any third resistor serves as the first end of the voltage divider module and is connected to the output end of the neutral or live wire connected in series with the first thermal circuit breaker; the end of the last third resistor that is connected to the adjacent third resistor serves as the third end of the voltage divider module and is connected to one end of the current limiting module; and the other end of the last third resistor that is not connected to any third resistor serves as the second end of the voltage divider module and is grounded.

[0022] And / or,

[0023] The current limiting module includes a fourth resistor. One end of the fourth resistor serves as one end of the current limiting module and is connected to the third end of the voltage divider module. The other end of the fourth resistor serves as the other end of the current limiting module and is connected to the control circuit.

[0024] In the above technical solution, multiple third resistors can divide the acquired voltage before outputting it to the subsequent circuit, preventing voltage signals exceeding the rated voltage of the control circuit from entering the control circuit. The fourth resistor can limit current signals exceeding the rated current of the control circuit from entering the control circuit, thereby reducing the probability of damage to the control circuit, improving its reliability, and extending its service life. This, in turn, extends the service life of the detection system.

[0025] In some exemplary embodiments, the first voltage detection circuit further includes a second rectifier module and a clamping module; one end of the second rectifier module is connected to the output terminal of the neutral or live wire connected in series with the first thermal circuit breaker, and the other end of the second rectifier module is connected to the first terminal of the voltage divider module; one end of the clamping module is connected to the third terminal of the voltage divider module and one end of the current limiting module, and the other end of the clamping module is connected to the power supply voltage; wherein, when the voltage output by the voltage divider module is greater than or equal to the rated voltage of the clamping module, the clamping module is turned on.

[0026] In the above technical solution, the second rectifier module can convert the AC power supplied by the live wire into DC power, improving the input adaptability and stability of the control circuit, thereby improving the reliability of the first voltage detection signal connected to the control circuit. When the voltage output by the voltage divider module is greater than or equal to the rated voltage of the clamping module, the clamping module is turned on to stabilize the voltage at the output of the voltage divider module at the rated voltage, thereby reducing the probability of damage to the control circuit and thus enabling the control circuit to have a longer service life, which in turn enables the detection system to have a longer service life, improving the reliability of the control circuit in detecting the plug based on the first voltage detection signal.

[0027] In some exemplary embodiments, the second rectifier module includes a second diode, the positive terminal of the second diode serving as one end of the second rectifier module and connected to the output terminal of the neutral or live wire connected in series with the first thermal circuit breaker, and the negative terminal of the second diode serving as the other end of the second rectifier module and connected to the first end of the voltage divider module.

[0028] And / or,

[0029] The clamping module includes a third diode. The positive terminal of the third diode serves as one end of the clamping module and is connected to the third terminal of the voltage divider module and one end of the current limiting module. The negative terminal of the third diode serves as the other end of the clamping module and is connected to the power supply voltage.

[0030] In the above technical solution, the second diode can convert the AC power supplied by the live wire into DC power, improving the input adaptability and stability of the control circuit, thereby improving the reliability of the first voltage detection signal connected to the control circuit. When the voltage at the output terminal of the voltage divider module is greater than or equal to the sum of the power supply voltage and the forward conduction voltage of the third diode, the positive and negative terminals of the third diode conduct, so that the voltage of the third diode is stabilized at the voltage value corresponding to the sum of the power supply voltage and the forward conduction voltage of the third diode. This reduces the probability of damage to the control circuit, thereby allowing the control circuit to have a longer service life, and thus allowing the detection system to have a longer service life.

[0031] In some exemplary embodiments, the first voltage detection circuit further includes a third filtering module and a fourth filtering module; one end of the third filtering module is connected to one end of the clamping module, the third end of the voltage divider module, and one end of the current limiting module, and the other end of the third filtering module is connected to the second end of the voltage divider module. One end of the fourth filtering module is connected to the other end of the current limiting module and the control circuit, and the other end of the fourth filtering module is grounded.

[0032] In the above technical solution, after the voltage divider module divides the DC power, it can be filtered by the third filter module to improve the stability and reliability of the signal input to the control circuit. The fourth filter module then filters the signal output by the current limiting module again. That is, through the dual filtering effect, the reliability of the first voltage detection signal output to the control circuit can be improved, thereby improving the accuracy and reliability of the control circuit in detecting the plug status based on the first voltage detection signal.

[0033] In some exemplary embodiments, the third filtering module includes a third capacitor. The first plate of the third capacitor serves as one end of the third filtering module and is connected to one end of the clamping module, the third end of the voltage divider module, and one end of the current limiting module. The second plate of the third capacitor serves as the other end of the third filtering module and is connected to the second end of the voltage divider module.

[0034] And / or,

[0035] The fourth filter module includes a fourth capacitor. The first plate of the fourth capacitor serves as one end of the fourth filter module and is connected to the other end of the current limiting module and the control circuit. The second plate of the fourth capacitor serves as the other end of the fourth filter module and is grounded.

[0036] In the above technical solution, the DC power after voltage division by the voltage divider module can be filtered by the third capacitor to improve the stability and reliability of the signal input to the control circuit. The fourth capacitor further filters the signal output by the current limiting module. This dual filtering improves the reliability of the first voltage detection signal output to the control circuit, thereby enhancing the accuracy and reliability of the control circuit's detection of the plug status based on this first voltage detection signal. Furthermore, the filter module composed of the third and fourth capacitors has a simple structure and small size.

[0037] Secondly, embodiments of this application provide a household appliance, including the detection system and plug described in any optional manner of the first aspect, the electrical load including a fan and / or a heating element; the plug is connected to the live wire and the neutral wire, and a first thermal circuit breaker and a first resistor are both disposed inside the plug.

[0038] In some exemplary embodiments, the household appliance also includes a thermostat connected to both the neutral and live wires.

[0039] Thirdly, embodiments of this application provide a method for detecting household appliances, applicable to any of the optional embodiments of the second aspect, the method comprising:

[0040] Powering on household appliances;

[0041] Preset operating time for electrical loads;

[0042] Acquire the first voltage detection signal;

[0043] When the first voltage detection signal is equal to the voltage threshold, it is determined that there is no spark discharge phenomenon in the plug;

[0044] When the first voltage detection signal is not equal to the voltage threshold, it is determined that there is a spark discharge phenomenon in the plug.

[0045] In the above technical solution, when spark discharge occurs in the plug, the detection method can promptly detect voltage fluctuations on the live or neutral wire and generate a corresponding first voltage detection signal to the control circuit. This allows the control voltage to promptly detect the plug's state based on the first voltage detection signal, thus determining whether spark discharge occurs. The detection reliability and accuracy are high. If spark discharge is detected, it is immediately reported for repair.

[0046] In some exemplary embodiments, after controlling the electrical load to operate for a preset time, the method further includes:

[0047] Acquire the second voltage detection signal;

[0048] When the first voltage detection signal is equal to the second voltage detection signal and the voltage threshold, it is determined that there is no spark discharge phenomenon in the plug and no tripping phenomenon in the temperature limiter.

[0049] When the second voltage detection signal is equal to the first voltage detection signal and the second voltage detection signal is less than the voltage threshold, it is determined that there is a spark discharge phenomenon in the plug and the temperature limiter does not trip.

[0050] When the second voltage detection signal is less than the first voltage detection signal and the first voltage detection signal is equal to the voltage threshold, it is determined that there is no spark discharge phenomenon in the plug and the temperature limiter trips.

[0051] When the second voltage detection signal is less than the first voltage detection signal, and the first voltage detection signal is less than the voltage threshold, it is determined that there is a spark discharge phenomenon in the plug and the temperature limiter trips.

[0052] In the above technical solution, the detection method can not only detect the spark discharge phenomenon of the plug based on the first voltage detection signal, but also detect the tripping phenomenon of the temperature limiter based on the second voltage detection signal. That is, the detection method can achieve dual detection, thereby improving detection reliability and accuracy. Secondly, the control circuit detects the spark discharge phenomenon of the plug through the first thermal circuit breaker, the first resistor, and the first voltage detection signal corresponding to the first voltage detection circuit. Simultaneously, it detects the tripping phenomenon of the temperature limiter through the second thermal circuit breaker, the second resistor, and the second voltage detection signal corresponding to the second voltage detection circuit. In other words, the control circuit uses two different voltage detection signals to detect both the plug and the temperature limiter, avoiding the risk of false alarms when using the same voltage detection signal, further improving detection accuracy and reliability. Attached Figure Description

[0053] To more clearly illustrate the technical solutions in the embodiments of this application, the accompanying drawings used in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0054] Figure 1 This is a schematic diagram of the modular structure of a household appliance in one embodiment of this application;

[0055] Figure 2 This is a schematic diagram of the circuit structure of the plug, electrical load, and detection system in one embodiment of this application;

[0056] Figure 3 This is a schematic diagram of the circuit structure of the plug, electrical load, and detection system in another embodiment of this application;

[0057] Figure 4 This is a schematic diagram of the circuit structure of the plug, electrical load, and detection system in another embodiment of this application;

[0058] Figure 5 This is a schematic diagram of the circuit structure of the plug, temperature limiter, electrical load and detection system in one embodiment of this application;

[0059] Figure 6 This is a schematic diagram of the circuit structure of the plug, thermostat, electrical load and detection system in another embodiment of this application;

[0060] Figure 7 This is a schematic diagram of the circuit structure of the plug, temperature limiter, electrical load and detection system in another embodiment of this application;

[0061] Figure 8 This is a schematic diagram of the circuit structure of the plug, temperature limiter, electrical load and detection system in another embodiment of this application;

[0062] Figure 9 This is a schematic diagram of the circuit structure of the plug, electrical load, and detection system in another embodiment of this application;

[0063] Figure 10 This is a schematic diagram of the circuit structure of the plug, electrical load, and detection system in another embodiment of this application;

[0064] Figure 11 This is a schematic diagram of the circuit structure of the plug, temperature limiter, electrical load and detection system in another embodiment of this application;

[0065] Figure 12 This is a schematic diagram of the module structure of the first voltage detection circuit in one embodiment of this application;

[0066] Figure 13 This is a schematic diagram of the circuit structure of the first voltage detection circuit in one embodiment of this application;

[0067] Figure 14 This is a flowchart of a method for testing household appliances in one embodiment of this application;

[0068] Figure 15 This is a flowchart of a method for testing household appliances in another embodiment of this application.

[0069] Explanation of reference numerals in the attached figures:

[0070] 1. Household appliance; 11. Body; 12. Plug; 13. Electrical load; 14. Temperature limiter; 2. Detection system; 21. Power supply circuit; 22. First voltage detection circuit; 221. Voltage divider module; 222. Current limiting module; 223. Second rectifier module; 224. Clamping module; 225. Third filter module; 226. Fourth filter module; 23. Power conversion circuit; 231. AC-DC converter; 232. First rectifier module; 233. First filter module; 234. Second filter module; 24. Control circuit; 25. Second voltage detection circuit;

[0071] ACN, Neutral wire; ACL, Live wire; K1, First thermal circuit breaker; K2, Second thermal circuit breaker; R1, First resistor; R2, Second resistor; R3, Third resistor; R4, Fourth resistor; VD1, First voltage detection signal; VD2, Second voltage detection signal; V, Voltage threshold; VDD, Power supply voltage; D1, First diode; D2, Second diode; D3, Third diode; C1, First capacitor; C2, Second capacitor; C3, Third capacitor; C4, Fourth capacitor; C5, Fifth capacitor; L, Inductance. Detailed Implementation

[0072] To make the objectives, technical solutions, and advantages of this application clearer, the following detailed description is provided in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the scope of this application.

[0073] Household appliances typically have plugs for electrical connection to sockets. For example, a heater is a high-powered small appliance. When connected, the plug draws electricity from the mains, allowing the heater to function properly. However, the heater plug has a metal part. After prolonged use, this metal part can age. An aged plug increases contact resistance with the socket, leading to poor contact and sparking (i.e., arcing).

[0074] Related technologies typically include additional anti-sparking detection equipment to detect spark discharge in the plug. This equipment detects sparking in the plug and prevents the heater from continuing to operate. Simultaneously, the heater emits audible and visual signals to alert the user that the plug has sparked and needs replacement. However, these anti-sparking detection devices suffer from significant size, footprint, and complex design issues.

[0075] Therefore, embodiments of this application provide a detection system, a household appliance, and a detection method for the household appliance. The detection system has a simple structure, small size, and high integration. It can not only detect the spark discharge phenomenon of the plug, but also protect the circuit under the spark discharge phenomenon.

[0076] The following description, in conjunction with the accompanying drawings, provides an exemplary description of the testing system, household appliance, and testing method for the household appliance provided in this application.

[0077] like Figure 1 As shown in the figure, this application embodiment provides a household appliance 1, which includes a body 11 and a plug 12 connected to the body 11. The plug 12 is used to connect to a socket. When the plug 12 is connected to the socket, the plug 12 is connected to the mains power to supply power to the body 11, so that the household appliance 1 can work normally.

[0078] To prevent spark discharge caused by poor contact between plug 12 and socket due to aging of plug 12, such as... Figure 2 As shown in the embodiment of this application, the household appliance 1 is equipped with a detection system 2. The detection system 2 can detect the spark discharge phenomenon of the plug 12 to determine whether the plug 12 has a spark discharge phenomenon. If it does, the detection system 2 can control the electrical load 13 in the household appliance 1 to stop working, so as to reduce the probability of damage to the household appliance 1 caused by the spark discharge phenomenon. Moreover, the detection system 2 is partially integrated into the plug 12, with a small size and small footprint, which is suitable for miniaturization.

[0079] In one example, such as Figure 2 As shown, the detection system 2 includes a power supply circuit 21, a first thermal circuit breaker K1, a first resistor R1, a first voltage detection circuit 22, a power conversion circuit 23, and a control circuit 24.

[0080] The power supply circuit 21 includes an Alternating Current Neutral (ACN) wire and an Alternating Current Live (ACL) wire. Both the ACN and ACL wires are connected to the plug 12 and the electrical load 13. The ACN wire is typically grounded, and the ACL wire is connected to the mains power supply. The ACN wire and ACL wires are used to supply power to the electrical load 13. A first thermal circuit breaker K1 is connected in series with either the ACN wire or the ACL wire. A first resistor R1 is connected in parallel with the K1 wire, and both are housed within the plug 12. A first voltage detection circuit 22 is connected to the output terminal of either the ACN wire or the ACL wire connected in series with the K1 wire. A power conversion circuit 23 is connected to both the ACL wire and the ACN wire. A control circuit 24 is connected to the ACN wire, the first voltage detection circuit 22, the electrical load 13, and the power conversion circuit 23.

[0081] It is worth noting that when poor contact occurs between plug 12 and socket, resulting in spark discharge, the voltage on the live wire ACL will fluctuate or drop momentarily. Correspondingly, the voltage on the neutral wire ACN will also fluctuate. For example, a drop in the voltage on the live wire ACL will cause a relative increase or fluctuation in the voltage on the neutral wire ACN. That is, when spark discharge occurs, both the voltage on the live wire ACL and the voltage on the neutral wire ACN will change. Therefore, by detecting the voltage fluctuation on either the live wire ACL or the neutral wire ACN, the presence of spark discharge can be detected. For this purpose, the first thermal circuit breaker K1 provided in this application can be connected in series with the live wire ACL or with the neutral wire ACN.

[0082] For example, such as Figure 2 As shown, the first thermal circuit breaker K1 can be connected in series with the live wire ACL. Correspondingly, the first resistor R1 is connected in parallel with the first thermal circuit breaker K1, that is, both ends of the first resistor R1 are also connected to the live wire ACL. At this time, the electrical energy on the live wire ACL is output to the power conversion circuit 23 through the first thermal circuit breaker K1 or the first resistor R1. That is, the output terminal of the live wire ACL faces the power conversion circuit 23. For this reason, the first voltage detection circuit 22 is set as shown in the figure. Figure 2 The location shown. At this time, the first voltage detection circuit 22 detects the voltage fluctuation on the live wire ACL. Or, as... Figure 3 As shown, the first thermal circuit breaker K1 in this application can be connected in series with the neutral line ACN. Correspondingly, the first resistor R1 is connected in parallel with the first thermal circuit breaker K1, that is, both ends of the first resistor R1 are also connected to the neutral line ACN. At this time, the first voltage detection circuit 22 is set as follows: Figure 3 The position is shown. At this time, the first voltage detection circuit 22 detects the voltage fluctuation on the neutral wire ACN. That is, whether the first thermal circuit breaker K1 is connected in series with the live wire ACL or the first thermal circuit breaker K1 is connected in series with the neutral wire ACN, the function of the first voltage detection circuit 22 is to detect the voltage signal and output it to the control circuit 24. The only difference is that the source of the signal is different; one is to collect the voltage fluctuation on the live wire ACL, and the other is to collect the voltage fluctuation on the neutral wire ACN. Therefore, the setting position of the first thermal circuit breaker K1, as well as the corresponding first resistor R1 and the first voltage detection circuit 22, can be selected according to actual needs.

[0083] When the first thermal circuit breaker K1 is connected in series with the neutral wire ACN, the only differences compared to when the first thermal circuit breaker K1 is connected in series with the live wire ACL are the placement of the first thermal circuit breaker K1, the first resistor R1, and the first voltage detection circuit 22, as well as the source of the signals collected and detected by the first voltage detection circuit 22. All other detection logic and processes are the same as when the first thermal circuit breaker K1 is connected in series with the live wire ACL. This application only uses the example of the first thermal circuit breaker K1 being connected in series with the live wire ACL to illustrate the detection system 2 provided in this application.

[0084] Meanwhile, the household appliance 1 in this application may include at least one of a heater, electric fan, rice cooker, air conditioner, refrigerator, and clothing handling device. In this embodiment, the household appliance 1 is explained using a heater as an example. When the household appliance 1 is a heater, the heater includes a housing and an electrical load 21 disposed within the housing. The electrical load 21 may include at least one of an AC load and a DC load. For example, the AC load may include at least one of an AC fan and an AC positive temperature coefficient (PTC) heating element. The DC load may include at least one of a DC fan and a DC heating element.

[0085] Correspondingly, the casing can have an air inlet and an air outlet, and an air duct is provided inside the casing, connecting the air inlet and the air outlet. The heating element and the fan are disposed within the air duct, with the fan positioned closer to the air inlet than the heating element, and the heating element positioned closer to the air outlet than the fan. When the fan is running, it draws air into the air duct from the air inlet and blows it out through the air outlet. If the heating element is in a heated state, it can heat the air in the air duct before blowing it out through the air outlet, thereby providing heating to the user.

[0086] It is understood that the shell material can be at least one of metal and plastic; however, in this embodiment, the material of the shell is not specifically limited. It is also understood that the shell shape can be at least one of cylinder or disk. In this embodiment, the shape of the shell is not specifically limited.

[0087] The following example illustrates the detection system 2 provided in this application, using the first thermal circuit breaker K1 connected in series with the live wire ACL and the household appliance 1 as a heater.

[0088] After the detection system 2 provided in this application is powered on, the control circuit 24 will control the electrical load 13 (e.g., a fan and / or a heating element) to run for a preset time. The preset time can be greater than or equal to 1 second and less than or equal to 4 seconds. Specifically, the first preset time can be 1 second, 2 seconds, 3 seconds, or 4 seconds. In this embodiment, the duration of the preset time is not specifically limited. After the electrical load 13 has run for the preset time, the first voltage detection circuit 22 will acquire the corresponding first voltage detection signal VD1 and output it to the control circuit 24. The control circuit 24 can determine whether there is a spark discharge phenomenon in the plug 12 based on the first voltage detection signal VD1.

[0089] Understandably, in the initial state, such as Figure 2 As shown, the first thermal circuit breaker K1 is in the closed state. The first thermal circuit breaker K1 has an internal metal spring to sense the current in its branch. When the current exceeds the rated value but does not reach the short-circuit current, the metal spring will bend due to the heat generated by the current. For example, the first thermal circuit breaker K1 can be a bimetallic thermal circuit breaker; in other embodiments, the first thermal circuit breaker K1 can also be of other forms. In this application embodiment, the specific form of the first thermal circuit breaker K1 is not limited. When there is a spark discharge phenomenon at the plug 12, the metal spring will spring open due to the heat generated by the current, causing the first thermal circuit breaker K1 to open the circuit (e.g., ...). Figure 4 (As shown). After the first thermal circuit breaker K1 is tripped, the first resistor R1 connected in parallel with it will be connected to the main power supply line. That is, at this time, the electrical energy on the live wire ACL will be output to the subsequent circuit (such as the power conversion circuit 23) through the first resistor R1.

[0090] A high-power electrical load 13, namely a fan and / or a heating element, is also connected to the live wire ACL and the neutral wire ACN. During the connection of this high-power load 13, the current flowing through the first resistor R1 will continuously increase. According to the formula U = IR (where U is the voltage, I is the current flowing through the first resistor R1, and R is the resistance of the first resistor R1), as the current flowing through the first resistor R1 continuously increases, since the resistance of the first resistor R1 remains constant, the voltage drop across the first resistor R1 will also continuously increase. When the voltage drop across the first resistor R1 increases, the voltage output to the power conversion circuit 23 through the first resistor R1 will also decrease.

[0091] The power conversion circuit 23 converts the AC power on the live wire ACL into DC power to supply the control circuit 24. For example, assuming the voltage output from the live wire ACL is 220V, after the voltage drop across the first resistor R1, the voltage may drop to 200V or even lower. When the voltage connected to the power conversion circuit 23 decreases, the corresponding voltage output from the power conversion circuit 23 to the control circuit 24 will also decrease. Since the voltage output from the power conversion circuit 23 to the control circuit 24 is the supply voltage for the control circuit 24, when the supply voltage decreases, the control circuit 24 cannot be powered normally and will lose power.

[0092] When the control circuit 24 loses power, the electrical load 13 under its control will also shut down accordingly. After the electrical load 13 shuts down, the AC load will become very small, and correspondingly, the voltage drop across the first resistor R1 will also become very small. At this time, the voltage connected to the power conversion circuit 23 will increase, and the voltage output by the power conversion circuit 23 to the control circuit 24 based on this voltage will also increase until the voltage output by the power conversion circuit 23 to the control circuit 24 returns to the supply voltage, causing the control circuit 24 to reset and restart based on the supply voltage and enter standby mode.

[0093] Thus, when spark discharge occurs at plug 12, the first thermal circuit breaker K1 will automatically trip, connecting the first resistor R1 to the main power supply line. Combined with the fact that the electrical load 13 will operate for a preset time after power-on, a significant voltage drop will occur across the first resistor R1, reducing the supply voltage to the control circuit 24 and causing it to shut down, putting the electrical load 13 into standby mode. At this time, because the electrical load 13 is in standby mode, its voltage will rise again to supply power to the control circuit 24. In other words, when spark discharge occurs at plug 12, the detection system 2 can promptly shut down the electrical load 13 and the control circuit 24, reducing the risk of damage to these components due to spark discharge and extending their service life.

[0094] After the control circuit 24 controls the electrical load 13 to run for a preset time after power-on, the first voltage detection circuit 23 will also acquire the corresponding first voltage detection signal VD1 and output it to the control circuit 24. The control circuit 24 can determine whether there is a spark discharge phenomenon in the plug 12 based on the first voltage detection signal VD1, so as to realize the detection of the plug 12.

[0095] In summary, when spark discharge occurs in plug 12, a significant voltage drop is generated across the first resistor R1, which promptly shuts off the electrical load 13 and control circuit 24, reducing the risk of damage to these components and extending their lifespan. Simultaneously, the first voltage detection circuit 23 can promptly detect voltage fluctuations on the live wire ACL or neutral wire ACN, generating a corresponding first voltage detection signal VD1 to the control circuit 24. This allows the control circuit 24 to promptly detect the state of plug 12 based on the first voltage detection signal VD1, determining whether spark discharge is present. The detection reliability and accuracy are high. If spark discharge is detected, it is immediately reported for repair. Furthermore, the detection system 2 has a simple circuit, requiring no additional anti-burn detection equipment, resulting in lower cost, smaller size, and smaller footprint. Moreover, both the first resistor R1 and the first thermal circuit breaker K1 are integrated within plug 12, demonstrating high integration and suitability for the miniaturization of household appliances. The small-sized, highly integrated detection system 2 provided in this application can not only reliably detect the spark discharge phenomenon of the plug, but also protect the circuit under the spark discharge phenomenon.

[0096] To enable the control circuit 24 to determine whether spark discharge exists in the plug 12 based on the first voltage detection signal VD1, specifically, in one example, the control circuit 24 presets a voltage threshold V. When the first voltage detection signal VD1 equals the voltage threshold V, it means that the first thermal circuit breaker K1 is connected to the main power supply line, and the control circuit 24 determines that there is no spark discharge in the plug 12. When the first voltage detection signal VD1 is not equal to the voltage threshold V, it means that the first resistor R1 is connected to the main power supply line, and the control circuit 24 determines that there is spark discharge in the plug 12.

[0097] The voltage threshold V can be the voltage at which the electrical load 13 operates normally, which is obtained by the control circuit 24 in advance through the first voltage detection circuit 23. In other embodiments, the voltage threshold V can also be a preset voltage. In this embodiment, the form of the voltage threshold V is not specifically limited.

[0098] In this example, when the first thermal circuit breaker K1 is on, the control circuit 24 can obtain the first voltage detection signal VD1 of the electrical load 13 during operation through the first voltage detection circuit 23. If the first thermal circuit breaker K1 is off, but the electrical load 13 is in operation, there will be a significant difference between the first voltage detection signal VD1 collected and output to the control circuit 24 by the first voltage detection circuit 23 and the preset voltage threshold V. This makes it easy for the control circuit 24 to distinguish between the first voltage detection signal VD1 and the voltage threshold V, and thus determine whether there is a spark discharge phenomenon in the plug 12. That is, by comparing the first voltage detection signal VD1 and the voltage threshold V, the control circuit 24 can accurately determine whether there is a spark discharge phenomenon in the plug 12, with high detection reliability and accuracy.

[0099] like Figure 5 As shown, a thermostat 14 is typically installed in the heater, connected to the live wire ACL and the neutral wire ACN. When the internal temperature of the heater is too high, the thermostat 14 will trip, its working principle being similar to that of the plug 12. Because the working principle of the thermostat 14 inside the heater is similar to that of the plug 12, the ignition of the plug 12 may generate a signal similar to an overheating signal. However, detection equipment in related technologies cannot distinguish whether this signal is a genuine overheating signal or interference caused by the ignition of the plug 12, easily leading to false detections. The detection system 2 provided in this application can accurately detect the tripping phenomenon of the thermostat 14, that is, it can detect both the ignition of the plug 12 and the high-temperature tripping of the thermostat 14, thus avoiding false alarms from both detection methods and improving detection accuracy and reliability.

[0100] Therefore, in one example, such as Figure 5 As shown, the household appliance 1 also includes a temperature limiter 14, which is connected to the neutral wire ACN and the live wire ACL. The detection system 2 also includes a second thermal circuit breaker K2, a second resistor R2, and a second voltage detection circuit 25. The second thermal circuit breaker K2 is connected in series with the neutral wire ACN or the live wire ACL and is located between the first thermal circuit breaker K1 and the power conversion circuit 23. Both the second thermal circuit breaker K2 and the second resistor R2 are located inside the temperature limiter 14. The second voltage detection circuit 25 is connected to the output terminal of the neutral wire ACN or the live wire ACL connected in series with the second thermal circuit breaker K2.

[0101] Understandably, the second thermal circuit breaker K2 needs to be connected in series with the first thermal circuit breaker K1 on the same line. That is, when the first thermal circuit breaker K1 is connected in series with the live wire ACL, the second thermal circuit breaker K2 is also connected in series with the live wire ACL. Correspondingly, the two ends of the second resistor R2 are also connected to the live wire ACL. At this time, the electrical energy on the live wire ACL is output to the power conversion circuit 23 through the second thermal circuit breaker K2 or the second resistor R2. That is, the output terminal of the live wire ACL faces the power conversion circuit 23. For this reason, the second voltage detection circuit 25 is set as follows: Figure 5 The positions are shown. Alternatively, when the first thermal circuit breaker K1 is connected in series with the neutral line ACN, the second thermal circuit breaker K2 is also connected in series with the neutral line ACN accordingly. The positions of the second resistor R2 and the second voltage detection circuit 25 are set in the same way, and will not be described in detail here.

[0102] The following example, using the case where both the first thermal circuit breaker K1 and the second thermal circuit breaker K2 are connected in series with the live wire ACL, will be used to further illustrate the detection system 2 provided in this application.

[0103] After the electrical load 13 (such as the fan and heating element of a heater) has been running for a preset time, the second voltage detection circuit 25 is used to obtain the corresponding second voltage detection signal VD2 and output it to the control circuit 24. The control circuit 24 is also used to determine whether the temperature limiter 14 has tripped based on the second voltage detection signal VD2.

[0104] Understandably, in the initial state, both the first thermal circuit breaker K1 and the second thermal circuit breaker K2 are in the closed state. The second thermal circuit breaker K2 also has an internal metal spring to sense the current in its branch. When the current exceeds the rated value but does not reach the short-circuit current, the metal spring will bend due to the heat generated by the current. For example, the second thermal circuit breaker K2 can be a bimetallic thermal circuit breaker; in other embodiments, the second thermal circuit breaker K2 can also be of other forms. In this application embodiment, the specific form of the second thermal circuit breaker K2 is not limited. When the temperature limiter 14 trips, the second thermal circuit breaker K2 will open. After the second thermal circuit breaker K2 opens, the second resistor R2 connected in parallel with it will be connected to the main power supply line. That is, at this time, the electrical energy on the live wire ACL will be output to the subsequent circuit (e.g., the power conversion circuit 23) through the second resistor R2.

[0105] A high-power electrical load 13, namely a fan and / or a heating element, is also connected to the live wire ACL and the neutral wire ACN. During the connection of this high-power load 13, the current flowing through the second resistor R2 continuously increases, and correspondingly, the voltage drop across the second resistor R2 also continuously increases. As the voltage drop across the second resistor R2 increases, the voltage output to the power conversion circuit 23 via the second resistor R2 also decreases. Because the voltage connected to the power conversion circuit 23 decreases, the voltage output by the power conversion circuit 23 to the control circuit 24 based on this voltage also decreases. Since the voltage output by the power conversion circuit 23 to the control circuit 24 is the supply voltage for the control circuit 24, when the supply voltage decreases, the control circuit 24 cannot be powered normally, and thus the control circuit 24 will lose power.

[0106] When the control circuit 24 loses power, the electrical load 13 it controls will also shut down. With the load 13 off, the AC load becomes very small, and consequently, the voltage drop across the second resistor R2 becomes very small. At this time, the voltage connected to the power conversion circuit 23 will increase, and the voltage output from the power conversion circuit 23 to the control circuit 24 based on this voltage will also increase until the voltage output from the power conversion circuit 23 to the control circuit 24 returns to the supply voltage. This causes the control circuit 24 to reset and restart based on the supply voltage and enter standby mode. In other words, when the temperature limiter 14 trips, the detection system 2 can promptly shut down the electrical load 13 and the control circuit 24, further reducing the risk of damage to the electrical load 13 and the control circuit 24, thereby extending their service life.

[0107] Thus, when the temperature limiter 14 trips, the second thermal circuit breaker K2 will automatically disconnect, allowing the second resistor R2 to connect to the main power supply line. The subsequent implementation process is the same as that of the first thermal circuit breaker K1, the first resistor R1, and the first voltage detection circuit 22 described above. For details, please refer to the descriptions of the first thermal circuit breaker K1, the first resistor R1, and the first voltage detection circuit 22; further details will not be elaborated here.

[0108] After the control circuit 24 controls the electrical load 13 to run for a preset period of time after power-on, the second voltage detection circuit 25 will acquire the corresponding second voltage detection signal VD2 and output it to the control circuit 24. The control circuit 24 can determine whether the temperature limiter 14 has tripped based on the second voltage detection signal VD2, thereby realizing the detection of the temperature limiter 14. Specifically, the second voltage detection circuit 25 can detect voltage fluctuations on the live wire ACL or the neutral wire ACN in a timely manner and generate the corresponding second voltage detection signal VD2 to the control circuit 24. This allows the control circuit 24 to detect the tripping of the temperature limiter 14 in a timely manner based on the second voltage detection signal VD2, thereby determining whether the temperature limiter 14 has tripped. The detection reliability and accuracy are high. If a tripping phenomenon is detected, it will be reported immediately for maintenance.

[0109] It is understandable that the control circuit 24 can detect not only the spark discharge phenomenon of the plug 12 based on the first voltage detection signal VD1, but also the tripping phenomenon of the temperature limiter 14 based on the second voltage detection signal VD2. That is, the control system 1 can achieve dual detection to improve detection reliability and accuracy. Secondly, the control circuit 24 detects the spark discharge phenomenon of the plug 12 through the first thermal circuit breaker K1, the first resistor R1, and the first voltage detection signal VD1 corresponding to the first voltage detection circuit 22. Simultaneously, it detects the tripping phenomenon of the temperature limiter 14 through the second thermal circuit breaker K2, the second resistor R2, and the second voltage detection signal VD2 corresponding to the second voltage detection circuit 25. In other words, the control circuit 24 detects the plug 12 and the temperature limiter 14 through two different voltage detection signals, avoiding the risk of false alarms when using the same voltage detection signal, further improving detection accuracy and reliability. Secondly, the second resistor R2 and the second thermal circuit breaker K2 are also integrated into the temperature limiter 14, further improving the integration and making it suitable for the miniaturization of household appliances 1. That is, the small-volume, highly integrated detection system 2 provided in this application can not only reliably detect and protect against spark discharge phenomena in the plug, but also reliably detect and protect against tripping phenomena in the temperature limiter 14.

[0110] In order for the control circuit 24 to determine whether there is a spark discharge phenomenon in the plug 12 based on the first voltage detection signal VD1, and at the same time, to determine whether there is a tripping phenomenon in the temperature limiter 14 based on the second voltage detection signal VD2.

[0111] For example, when both the first thermal circuit breaker K1 and the second thermal circuit breaker K2 are closed, the first voltage detection signal VD1 and the second voltage detection signal VD2 received by the control circuit 24 are equal to the voltage threshold V, that is, neither the first voltage detection signal VD1 nor the second voltage detection signal VD2 fluctuates. The control circuit 24 determines that there is no spark discharge phenomenon in the plug 12 at this time, and the temperature limiter 14 does not trip.

[0112] When the first thermal circuit breaker K1 is open and the second thermal circuit breaker K2 is closed, the second voltage detection signal VD2 received by the control circuit 24 is equal to the first voltage detection signal VD1, and the second voltage detection signal VD2 is less than the voltage threshold V. The control circuit 24 determines that there is a spark discharge phenomenon in the plug 12 and that the temperature limiter 14 does not trip.

[0113] When the first thermal circuit breaker K1 is closed and the second thermal circuit breaker K2 is open, the second voltage detection signal VD2 received by the control circuit 24 is less than the first voltage detection signal VD1, and the first voltage detection signal VD1 is equal to the voltage threshold V. The control circuit 24 determines that there is no spark discharge phenomenon in the plug 12 and that the temperature limiter 14 trips.

[0114] When both the first thermal circuit breaker K1 and the second thermal circuit breaker K2 are open, the second voltage detection signal VD2 received by the control circuit 24 is less than the first voltage detection signal VD1, and the first voltage detection signal VD1 is less than the voltage threshold V. The control circuit 24 determines that there is a spark discharge phenomenon in the plug 12 and that the temperature limiter 14 trips.

[0115] Correspondingly, when either the first thermal circuit breaker K1 or the second thermal circuit breaker K1 is open, and the electrical load 13 is in operation, there is a significant difference between the first voltage detection signal VD1 and the second voltage detection signal VD2, collected and output to the control circuit 24 by the first voltage detection circuit 23 and the second voltage detection circuit 25, and the preset voltage threshold V. This allows the control circuit 24 to easily distinguish between the first voltage detection signal VD1, the second voltage detection signal VD2, and the voltage threshold V, thereby determining whether there is a spark discharge phenomenon in the plug 12 and whether the temperature limiter 14 has tripped. In other words, by comparing the first voltage detection signal VD1, the second voltage detection signal VD2, and the voltage threshold V, the control circuit 24 can accurately determine whether there is a spark discharge phenomenon in the plug 12 and whether the temperature limiter 14 has tripped. By comparing the three voltage values, the risk of false alarms can be avoided, resulting in high detection reliability and accuracy.

[0116] Power conversion circuit 23 is used to convert the AC power supplied by the live wire ACL into the supply voltage of control circuit 24. In one example, such as Figure 6As shown, the power conversion circuit 23 includes an AC-DC converter 231. The input terminal of the AC-DC converter 231 is connected to the live wire ACL, and the output terminal of the AC-DC converter 231 is connected to the control circuit 24. The AC-DC converter 231 is used to convert the AC power provided by the live wire ACL into DC power and output it to the control circuit 24.

[0117] In this example, the AC-DC converter 231 can convert the AC power output from the live wire ACL into DC power, thereby enabling the DC power to power the DC load (i.e., the control circuit 24), ensuring the reliability of the power supply to the control circuit 24, and thus ensuring the operational reliability of the control circuit 24.

[0118] To further improve the power supply reliability of control circuit 24, in one example, such as Figure 7 As shown, the power conversion circuit 23 also includes a first rectifier module 232, a first filter module 233, and a second filter module 234. The first rectifier module 232 is connected to the live wire ACL, and the first filter module 233 is connected to the first rectifier module 232, the neutral wire ACN, and the input terminal of the AC-DC converter 231. The second filter module 234 is connected to the output terminal of the AC-DC converter 231, the neutral wire ACN, and the control circuit 24, and is connected to the power supply voltage VDD.

[0119] The FireWire ACL typically provides alternating current (AC), while the AC-DC converter 231 requires a DC input. Therefore, the first rectifier module 232 converts the AC power from the FireWire ACL into pulsating direct current (DC). This provides an initial DC signal to the subsequent first filter module 233 and the AC-DC converter 231, improving the input adaptability and stability of the AC-DC converter 231, thereby enhancing its conversion stability.

[0120] Optionally, in the embodiments of this application, such as Figure 8 As shown, the first rectifier module 232 may include a first diode D1, with the positive terminal of the first diode D1 connected to the live wire ACL and the negative terminal of the first diode D1 connected to the first filter module 233. In other embodiments, the first rectifier module 232 may also take other forms, and this application does not impose specific limitations on this.

[0121] The first filter module 233 can significantly reduce the ripple voltage of the output voltage of the first rectifier module 232, thereby improving the purity of the DC output. At the same time, the first filter module 233 can also suppress high-frequency noise, preventing high-frequency noise from entering the AC-DC converter 231 and affecting its operational stability, thereby further improving the input adaptability and stability of the AC-DC converter 231.

[0122] Optionally, in the embodiments of this application, such as Figure 8 As shown, the first filtering module 233 may include a first capacitor C1, an inductor L, and a second capacitor C2. The first plate of the first capacitor C1 is connected to the first rectifier module 232 (the negative terminal of the first diode D1) and one end of the inductor L. The second plate of the first capacitor C1 is connected to the neutral line ACN. The other end of the inductor L is connected to the first plate of the second capacitor C2 and the input terminal of the AC-DC converter 231. The second plate of the second capacitor C2 is also connected to the neutral line ACN. The first capacitor C1 is used to filter out high-frequency ripple, the inductor L is connected in series in the main power supply line to block high-frequency signals from passing through, and the second capacitor C2 is used to further filter out residual AC components. In other embodiments, the first filtering module 233 may also be in other forms, such as an LC filter consisting of a capacitor and an inductor. This application does not impose specific limitations on this.

[0123] The second filtering module 234 is used to filter the power supply voltage generated by the AC-DC converter 231 to improve the purity of the power supply voltage output to the control circuit 24, thereby improving the stability and reliability of the control circuit 24 based on the power supply voltage.

[0124] Optionally, in the embodiments of this application, such as Figure 8 As shown, the second filter module 234 may include a fifth capacitor C5. The first plate of the fifth capacitor C5 is connected to the neutral line ACN and connected to the power supply voltage VDD. The second plate of the fifth capacitor C5 is connected to the output terminal of the AC-DC converter 231 and the control circuit 24. In other embodiments, the second filter module 234 may also take other forms, which are not specifically limited in this application.

[0125] For example, please refer to Figure 9 and Figure 10 Household appliance 1 is only equipped with plug 12. When the power conversion circuit 23 includes the above-mentioned components, the specific architecture is as follows: Figure 9 and Figure 10 As shown.

[0126] To enable the first voltage detection circuit 22 and the second voltage detection circuit 25 provided in this application to reliably acquire the corresponding voltage signals, please refer to an example. Figure 11As shown, the first voltage detection circuit 22 includes a voltage divider module 221 and a current limiting module 222. The first terminal of the voltage divider module 221 is connected to the output terminal of either the neutral wire ACN or the live wire ACL connected in series with the first thermal circuit breaker K1. That is, when the first thermal circuit breaker K1 is connected in series with the live wire ACL, the first terminal of the corresponding voltage divider module 221 is connected to the output terminal of the live wire ACL; when the first thermal circuit breaker K1 is connected in series with the neutral wire ACN, the first terminal of the corresponding voltage divider module 221 is connected to the output terminal of the neutral wire ACN. The second terminal of the voltage divider module 221 is grounded. One terminal of the current limiting module 222 is connected to the third terminal of the voltage divider module 221, and the other terminal of the current limiting module 222 is connected to the control circuit 24.

[0127] It is understood that in this embodiment, the function of the second voltage detection circuit 25 is the same as that of the first voltage detection circuit 22, both being voltage acquisition. Therefore, the second voltage detection circuit 25 can use the same circuit architecture as the first voltage detection circuit 22. For this reason, this application only provides an exemplary description of the circuit architecture of the first voltage detection circuit 22; the second voltage detection circuit 25 can refer to the circuit architecture of the first voltage detection circuit 22. In other embodiments, the second voltage detection circuit 25 can use other voltage detection circuits, and this application does not impose specific limitations on this.

[0128] The voltage divider module 221 can divide the acquired voltage before outputting it to the subsequent circuit (e.g., control circuit 24), preventing voltage signals exceeding the rated voltage of control circuit 24 from entering control circuit 24, thereby reducing the probability of control circuit 24 being damaged, thus enabling control circuit 24 to have a longer service life, and consequently enabling detection system 2 to have a longer service life.

[0129] Optionally, in the embodiments of this application, such as Figure 13 As shown, the voltage divider module 221 may include multiple third resistors R3 connected in series. The first third resistor R3, whose end is not connected to any other third resistor R3, serves as the first terminal of the voltage divider module 221 and is connected to the output terminal of the neutral wire ACN or the live wire ACL connected in series with the first thermal circuit breaker K1. The last third resistor R3, whose end is connected to the adjacent third resistor R3, serves as the third terminal of the voltage divider module 221 and is connected to one end of the current limiting module 222. The other end of the last third resistor R3, which is not connected to any other third resistor R3, serves as the second terminal of the voltage divider module 221 and is grounded.

[0130] For example, the illustration shows a voltage divider module 221 comprising three third resistors R3 connected in series. The end of the first third resistor R3 not connected to the second third resistor R3 serves as the first terminal of the voltage divider module 221. The end of the third third resistor R3 connected to the second third resistor R3 serves as the third terminal of the voltage divider module 221, and the end of the third third resistor R3 not connected to the second third resistor R3 also serves as the third terminal of the voltage divider module 221. It is understood that in other embodiments, the voltage divider module 221 may include other numbers of third resistors, or the voltage divider module 221 may be in other forms. In this embodiment, the specific form of the voltage divider module 221 is not limited.

[0131] The current limiting module 222 can limit the current signal that exceeds the rated current of the control circuit 24 from entering the control circuit 24, thereby reducing the probability of damage to the control circuit 24, improving the reliability of the control circuit 24, and enabling the control circuit 24 to have a longer service life, which in turn enables the detection system 2 to have a longer service life.

[0132] Optionally, in the embodiments of this application, such as Figure 13 As shown, the current limiting module 222 may include a fourth resistor R4. One end of the fourth resistor R4 serves as one end of the current limiting module 222, connected to the third end of the voltage divider module 221 (i.e., one end of the third resistor R3). The other end of the fourth resistor R4 serves as the other end of the current limiting module 222, connected to the control circuit 24. When the current limiting module 222 uses the fourth resistor R4, only one resistor element is needed to achieve the purpose of current limiting, resulting in lower cost and easier installation. In other embodiments, the current limiting module 222 may also use other current limiting circuits or devices; this application does not impose specific limitations on this.

[0133] In one example, such as Figure 12 As shown, the first voltage detection circuit 22 also includes a second rectifier module 223 and a clamping module 224. One end of the second rectifier module 223 is connected to the output terminal of the neutral line ACN or the live line ACL connected in series with the first thermal circuit breaker K1. That is, when the first thermal circuit breaker K1 is connected in series with the live line ACL, one end of the corresponding second rectifier module 223 is connected to the output terminal of the live line ACL; when the first thermal circuit breaker K1 is connected in series with the neutral line ACN, one end of the corresponding second rectifier module 223 is connected to the output terminal of the neutral line ACN. The other end of the second rectifier module 223 is connected to the first end of the voltage divider module 221, one end of the clamping module 224 is connected to the third end of the voltage divider module 221 and one end of the current limiting module 222, and the other end of the clamping module 224 is connected to the power supply voltage VDD.

[0134] The second rectifier module 223 converts the AC power supplied by the live wire ACL into DC power, improving the input adaptability and stability of the control circuit 24, thereby enhancing the reliability of the first voltage detection signal VD1 connected to the control circuit 2. Optionally, in this embodiment, as... Figure 13 As shown, the second rectifier module 223 includes a second diode D2. The positive terminal of the second diode D2 serves as one end of the second rectifier module 223 and is connected to the output terminal of the neutral wire ACN or the live wire ACL connected in series with the first thermal circuit breaker K1. The negative terminal of the second diode D2 serves as the other end of the second rectifier module 223 and is connected to the first terminal of the voltage divider module 221. In other embodiments, the second rectifier module 223 may also use other current limiting circuits or devices; this application does not impose specific limitations on this.

[0135] When the voltage output by the voltage divider module 221 is greater than or equal to the rated voltage of the clamping module 224, the clamping module 224 is turned on to stabilize the voltage at the output of the voltage divider module 221 at the rated voltage, thereby reducing the probability of damage to the control circuit 24 and thus enabling the control circuit 24 to have a longer service life, which in turn enables the detection system 2 to have a longer service life, further improving the reliability of the control circuit 24 in detecting the plug 12 based on the first voltage detection signal VD1.

[0136] Optionally, in the embodiments of this application, such as Figure 13 As shown, the clamping module 224 includes a third diode D3. The positive terminal of the third diode D3 serves as one end of the clamping module 224, connected to the third terminal of the voltage divider module 221 and one end of the current limiting module 222. The negative terminal of the third diode D3 serves as the other end of the clamping module 224, connected to the power supply voltage VDD. When the voltage at the output terminal of the voltage divider module 221 is greater than or equal to the sum of the power supply voltage and the forward conduction voltage of the third diode D3, the positive and negative terminals of the third diode D3 conduct, thereby stabilizing the voltage of the third diode D3 at the voltage value corresponding to the sum of the power supply voltage VDD and the forward conduction voltage of the third diode D3. This reduces the probability of damage to the control circuit 24, thus extending the service life of the control circuit 24 and consequently, the service life of the detection system 2. In other embodiments, the clamping module 224 may take other forms, which are not specifically limited in this application.

[0137] To further improve the reliability of the first voltage detection signal VD1 output from the first voltage detection circuit 22 to the control circuit 24, in one example, such as Figure 12As shown, the first voltage detection circuit 22 also includes a third filter module 225 and a fourth filter module 226. One end of the third filter module 225 is connected to one end of the clamping module 224, the third end of the voltage divider module 221, and one end of the current limiting module 222. The other end of the third filter module 225 is connected to the second end of the voltage divider module 221 via a common ground connection. One end of the fourth filter module 226 is connected to the other end of the current limiting module 222 and the control circuit 24. The other end of the fourth filter module 226 is grounded.

[0138] In this example, after the voltage divider module 221 divides the DC power, it can be filtered by the third filter module 225 to improve the stability and reliability of the signal input to the control circuit 24. The fourth filter module 226 then filters the signal output by the current limiting module 222 again. That is, through the dual filtering effect, the reliability of the first voltage detection signal VD1 output to the control circuit 24 can be improved, thereby improving the accuracy and reliability of the control circuit 24 in detecting the state of the plug 12 based on the first voltage detection signal VD1.

[0139] Optionally, in the embodiments of this application, such as Figure 13 As shown, the third filter module 225 includes a third capacitor C3. The first plate of the third capacitor C3 serves as one end of the third filter module 225, connected to one end of the clamping module 224, the third end of the voltage divider module 221, and one end of the current limiting module 222. The second plate of the third capacitor C3 serves as the other end of the third filter module 225, and is grounded together with the second end of the voltage divider module 221. The fourth filter module 226 includes a fourth capacitor C4. The first plate of the fourth capacitor C4 serves as one end of the fourth filter module 226, connected to the other end of the current limiting module 222 and the control circuit 24. The second plate of the fourth capacitor C4 serves as the other end of the fourth filter module 226, grounded.

[0140] After voltage division by voltage divider module 221, the DC current can be filtered by third capacitor C3 to improve the stability and reliability of the signal input to control circuit 24. Fourth capacitor C4 further filters the signal output by current limiting module 222. This dual filtering improves the reliability of the first voltage detection signal VD1 output to control circuit 24, thereby enhancing the accuracy and reliability of control circuit 24's detection of plug 12's status based on this signal. Furthermore, the filtering module formed by third capacitor C3 and fourth capacitor C4 has a simple structure and small size. In other embodiments, third filtering module 225 and fourth filtering module 226 can also take other forms; this application does not impose specific limitations on these.

[0141] It is worth noting that the parameters of each component in the first voltage detection circuit 22 (such as the third resistor R3, the fourth resistor R4, etc.) are set based on the series connection position of the first thermal circuit breaker K1. That is, the parameter selection of each component is different depending on the series connection position of the first thermal circuit breaker K1, so as to adapt to different voltage acquisition.

[0142] In one example, the detection system 2 may further include a prompting device (not shown), connected to the control circuit 24, for issuing a prompt message. When the control circuit 24 determines, via the first voltage detection signal VD1, that there is a spark discharge in the plug 12, and / or when the control circuit 24 determines, via the second voltage detection signal VD2, that the temperature limiter 14 has tripped, the control circuit 24 can control the prompting device to issue a prompt message to remind the user that the plug 12 needs to be disconnected from the socket, or that the plug 12 needs to be replaced, or that the temperature limiter 14 is malfunctioning.

[0143] Optionally, in this embodiment, the prompt information includes at least one of display information, sound information, and light information. In other embodiments, the prompt information may take other forms, and this application does not impose specific limitations on this.

[0144] Optionally, in this embodiment, the control circuit 24 may be a microcontroller unit (MCU). In other embodiments, the control circuit 24 may be in other forms. This application does not impose specific limitations on this.

[0145] In summary, when the household appliance 1 is only equipped with a plug 12, the control circuit 24 in the detection system 1 provided in this application can detect the spark discharge phenomenon of the plug 12 based on the first voltage detection signal VD1. When the plug 12 has a spark discharge phenomenon, it can generate a large voltage drop across the first resistor R1, thereby shutting off the electrical load 13 and the control circuit 24 in time, reducing the risk of damage to the electrical load 13 and the control circuit 24 caused by the spark discharge, and extending the service life of the electrical load 13, the control circuit 24, and other circuits on the line. At the same time, the first voltage detection circuit 23 can detect the voltage fluctuation on the live wire ACL or the neutral wire ACN in time and generate the corresponding first voltage detection signal VD1 to the control circuit 24, so that the control voltage 24 can detect the state of the plug 12 in time based on the first voltage detection signal VD1 to determine whether the plug 12 has a spark discharge phenomenon. The detection reliability and detection accuracy are high. If a spark discharge phenomenon is determined to exist, it is immediately reported for repair. Secondly, the detection system 2 has a simple circuit, requiring no additional anti-burn detection equipment, resulting in lower cost, smaller size, and smaller footprint. Furthermore, both the first resistor R1 and the first thermal circuit breaker K1 are integrated within the plug 12, demonstrating high integration and suitability for the miniaturization of household appliances 1. In other words, the small-sized, highly integrated detection system 2 provided by this application can not only reliably detect spark discharge phenomena in the plug but also provide circuit protection under spark discharge conditions.

[0146] When the household appliance 1 is equipped with a plug 12 and a thermostat 14, the control circuit 24 in the detection system 1 provided in this application can not only detect the spark discharge phenomenon of the plug 12 based on the first voltage detection signal VD1, but also detect the tripping phenomenon of the thermostat 14 based on the second voltage detection signal VD2. That is, the control system 1 can achieve dual detection to improve detection reliability and accuracy. Secondly, the control circuit 24 detects the spark discharge phenomenon of the plug 12 through the first thermal circuit breaker K1, the first resistor R1, and the first voltage detection signal VD1 corresponding to the first voltage detection circuit 22. Simultaneously, it detects the tripping phenomenon of the thermostat 14 through the second thermal circuit breaker K2, the second resistor R2, and the second voltage detection signal VD2 corresponding to the second voltage detection circuit 25. In other words, the control circuit 24 detects the plug 12 and the thermostat 14 through two different voltage detection signals, avoiding the risk of false alarms when using the same voltage detection signal, further improving detection accuracy and reliability. Secondly, the second resistor R2 and the second thermal circuit breaker K2 are also integrated into the temperature limiter 14, further improving the integration and making it suitable for the miniaturization of household appliances 1. That is, the small-volume, highly integrated detection system 2 provided in this application can not only reliably detect and protect against spark discharge phenomena in the plug, but also reliably detect and protect against tripping phenomena in the temperature limiter 14.

[0147] This application also provides a method for testing household appliances. In one example, Figure 14 This is a schematic flowchart of a method for testing household appliances provided in an embodiment of this application; the method 100 includes S101 to S105; S101 to S105 are described in detail below.

[0148] The detection method is applied to the aforementioned household appliance 1, which may include, for example, Figures 1 to 13 The detection system 2 shown. For example, such as... Figure 2 As shown, the detection system 2 includes a power supply circuit 21, a first thermal circuit breaker K1, a first resistor R1, a first voltage detection circuit 22, a power conversion circuit 23, and a control circuit 24. The power supply circuit 21 includes a neutral wire ACN and a live wire ACL, both connected to the plug 12 and the electrical load 13. The first thermal circuit breaker K1 is connected in series with either the neutral wire ACN or the live wire ACL. The first resistor R1 is connected in parallel with the first thermal circuit breaker K1, and both are housed within the plug 12. The first voltage detection circuit 22 is connected to the output terminal of either the neutral wire ACN or the live wire ACL connected in series with the first thermal circuit breaker K1. The power conversion circuit 23 is connected to both the live wire ACL and the neutral wire ACN. The control circuit 24 is connected to the neutral wire ACN, the first voltage detection circuit 22, the electrical load 13, and the power conversion circuit 23.

[0149] S101. Power on household appliances.

[0150] In this embodiment of the application, when the plug 12 is connected to the socket, the mains power can supply power to the plug 12 through the socket so that the household appliance 1 can be powered on.

[0151] S102, Preset operating time of the electrical load.

[0152] In this embodiment, the preset duration can be greater than or equal to 1 second and less than or equal to 4 seconds. Specifically, the first preset duration can be 1 second, 2 seconds, 3 seconds, or 4 seconds. In this embodiment, the duration of the preset duration is not specifically limited.

[0153] S103. Obtain the first voltage detection signal.

[0154] After the electrical load 13 has been running for a preset period of time, the first voltage detection circuit 22 will acquire the corresponding first voltage detection signal VD1 and output it to the control circuit 24. The control circuit 24 can determine whether there is a spark discharge phenomenon in the plug 12 based on the first voltage detection signal VD1, with high detection reliability and accuracy. If a spark discharge phenomenon is detected, it will be reported immediately for maintenance.

[0155] Specifically, it is understandable that in the initial state, such as Figure 2 As shown, the first thermal circuit breaker K1 is in the closed state. The first thermal circuit breaker K1 has an internal metal spring to sense the current in its branch. When the current exceeds the rated value but does not reach the short-circuit current, the metal spring will bend due to the heat generated by the current. For example, the first thermal circuit breaker K1 can be a bimetallic thermal circuit breaker; in other embodiments, the first thermal circuit breaker K1 can also be of other forms. In this application embodiment, the specific form of the first thermal circuit breaker K1 is not limited. When there is a spark discharge phenomenon at the plug 12, the metal spring will spring open due to the heat generated by the current, causing the first thermal circuit breaker K1 to open the circuit (e.g., ...). Figure 4 (As shown). After the first thermal circuit breaker K1 is tripped, the first resistor R1 connected in parallel with it will be connected to the main power supply line. That is, at this time, the electrical energy on the live wire ACL will be output to the power conversion circuit 23 through the first resistor R1.

[0156] A high-power electrical load 13, namely a fan and / or a heating element, is also connected to the live wire ACL and the neutral wire ACN. During the connection of the high-power electrical load 13, the current flowing through the first resistor R1 will continuously increase, and correspondingly, the voltage drop across the first resistor R1 will also continuously increase. When the voltage drop across the first resistor R1 increases, the voltage output to the power conversion circuit 23 through the first resistor R1 will also decrease.

[0157] The power conversion circuit 23 converts the AC power on the live wire ACL into DC power to supply the control circuit 24. For example, assuming the voltage output from the live wire ACL is 220V, after the voltage drop across the first resistor R1, the voltage may drop to 200V or even lower. When the voltage connected to the power conversion circuit 23 decreases, the corresponding voltage output from the power conversion circuit 23 to the control circuit 24 will also decrease. Since the voltage output from the power conversion circuit 23 to the control circuit 24 is the supply voltage for the control circuit 24, when the supply voltage decreases, the control circuit 24 cannot be powered normally and will lose power.

[0158] When the control circuit 24 loses power, the electrical load 13 under its control will also shut down accordingly. After the electrical load 13 shuts down, the AC load will become very small, and correspondingly, the voltage drop across the first resistor R1 will also become very small. At this time, the voltage connected to the power conversion circuit 23 will increase, and the voltage output by the power conversion circuit 23 to the control circuit 24 based on this voltage will also increase until the voltage output by the power conversion circuit 23 to the control circuit 24 returns to the supply voltage, causing the control circuit 24 to reset and restart based on the supply voltage and enter standby mode.

[0159] Thus, when spark discharge occurs at plug 12, the first thermal circuit breaker K1 will automatically trip, connecting the first resistor R1 to the main power supply line. Combined with the fact that the electrical load 13 will operate for a preset time after power-on, a significant voltage drop will occur across the first resistor R1, reducing the supply voltage to the control circuit 24 and causing it to shut down, putting the electrical load 13 into standby mode. At this time, because the electrical load 13 is in standby mode, its voltage will rise again to supply power to the control circuit 24. In other words, when spark discharge occurs at plug 12, the detection system 2 can promptly shut down the electrical load 13 and the control circuit 24, reducing the risk of damage to these components due to spark discharge and extending their service life.

[0160] S104. When the first voltage detection signal is equal to the voltage threshold, it is determined that there is no spark discharge phenomenon in the plug.

[0161] In this embodiment, the control circuit 24 has a preset voltage threshold V. When the first thermal circuit breaker K1 is turned on, the first voltage detection signal VD1 connected to the control circuit 24 is equal to the voltage threshold V, indicating that the first thermal circuit breaker K1 is connected to the main power supply line at this time, and the control circuit 24 determines that there is no spark discharge phenomenon in the plug 12.

[0162] S105. When the first voltage detection signal is not equal to the voltage threshold, it is determined that there is a spark discharge phenomenon in the plug.

[0163] In this embodiment, when the first thermal circuit breaker K1 is open and the electrical load 13 is in operation, there is a significant difference between the first voltage detection signal VD1 collected and output to the control circuit 24 by the first voltage detection circuit 23 and the preset voltage threshold V. This makes it easy for the control circuit 24 to distinguish between the first voltage detection signal VD1 and the voltage threshold V, thereby determining whether a spark discharge phenomenon exists in the plug 12. In other words, by comparing the first voltage detection signal VD1 and the voltage threshold V, the control circuit 24 can accurately determine whether a spark discharge phenomenon exists in the plug 12, resulting in high detection reliability and accuracy.

[0164] In summary, when spark discharge occurs in plug 12, the first voltage detection circuit 23 can promptly detect voltage fluctuations on the live wire ACL or neutral wire ACN, and generate a corresponding first voltage detection signal VD1 to the control circuit 24. This allows the control circuit 24 to promptly detect the state of plug 12 based on the first voltage detection signal VD1 to determine whether spark discharge occurs. The detection reliability and accuracy are high. If spark discharge is detected, it is immediately reported for maintenance.

[0165] In this embodiment, the household appliance 1 may include at least one of a heater, an electric fan, a rice cooker, an air conditioner, a refrigerator, and a clothes handling device. In this embodiment, a heater is used as an example to illustrate the household appliance 1. When the household appliance 1 is a heater, the heater includes a housing and an electrical load 21 disposed within the housing. The electrical load 21 may include at least one of an AC load and a DC load. For example, an AC load may include at least one of an AC fan and a heating element. A DC load may include at least one of a DC fan and a DC heating element.

[0166] When the household appliance 1 is used as a heater, if there is a spark discharge at the plug 12, the first thermal circuit breaker K1 will trip. After the first thermal circuit breaker K1 trips, the first resistor R1 connected in parallel with it will be connected to the main power supply line. That is, at this time, the electrical energy on the live wire ACL will be output to the power conversion circuit 23 through the first resistor R1. During the process of connecting the high-power electrical load 13 (fan and heating element) in the heater, the current flowing through the first resistor R1 will continuously increase, and correspondingly, the voltage drop generated on the first resistor R1 will also continuously increase. When the voltage drop on the first resistor R1 increases, the voltage output to the power conversion circuit 23 through the first resistor R1 will also decrease. After the voltage connected to the power conversion circuit 23 decreases, the voltage output by the power conversion circuit 23 to the control circuit 24 based on this voltage will also decrease. Since the voltage output by the power conversion circuit 23 to the control circuit 24 is the supply voltage of the control circuit 24, when the supply voltage decreases, the control circuit 24 cannot be powered normally, and the control circuit 24 will lose power.

[0167] When the control circuit 24 loses power, the fan and heating element it controls will also shut down. With the fan and heating element off, the AC load becomes very small, and correspondingly, the voltage drop across the first resistor R1 also becomes very small. At this time, the voltage connected to the power conversion circuit 23 will increase, and the voltage output from the power conversion circuit 23 to the control circuit 24 based on this voltage will also increase until the voltage output from the power conversion circuit 23 to the control circuit 24 returns to the supply voltage. This causes the control circuit 24 to reset and restart based on the supply voltage and enter standby mode. Correspondingly, the heater remains in standby mode.

[0168] Heaters typically also include a thermostat 14. When the internal temperature of the heater becomes too high, the thermostat 14 trips. To ensure that the detection method provided in this application can simultaneously detect the sparking of the plug 12 and the high-temperature tripping of the thermostat 14, thus avoiding false alarms from both detection methods, in one example... Figure 15 This is a schematic flowchart of a method for testing household appliances provided in an embodiment of this application. After step S102, the method 200 includes S201 to S205; S201 to S105 are described in detail below.

[0169] The driving method is applied to the aforementioned household appliance 1 (taking a heater as an example), and the heater may include, for example, Figures 1 to 13 The detection system 2 shown. For example, such as... Figure 5 As shown, the heater also includes a temperature limiter 14, which is connected to the neutral wire ACN and the live wire ACL. The detection system 2 also includes a second thermal circuit breaker K2, a second resistor R2, and a second voltage detection circuit 25. The second thermal circuit breaker K2 is connected in series with the neutral wire ACN or the live wire ACL and is located between the first thermal circuit breaker K1 and the power conversion circuit 23. Both the second thermal circuit breaker K2 and the second resistor R2 are located inside the temperature limiter 14. The second voltage detection circuit 25 is connected to the output terminal of the neutral wire ACN or the live wire ACL connected in series with the second thermal circuit breaker K2.

[0170] S201, Obtain the second voltage detection signal.

[0171] In this embodiment, after the fan and heating element have been running for a preset time, the second voltage detection circuit 25 is used to acquire the corresponding second voltage detection signal VD2 and output it to the control circuit 24. The control circuit 24 is also used to determine whether the temperature limiter 14 has tripped based on the second voltage detection signal VD2.

[0172] When the temperature limiter 14 trips, the second thermal circuit breaker K2 will automatically disconnect, allowing the second resistor R2 to connect to the main power supply line. The subsequent implementation process is the same as that of the first thermal circuit breaker K1, the first resistor R1, and the first voltage detection circuit 22 described above. For details, please refer to the descriptions of the first thermal circuit breaker K1, the first resistor R1, and the first voltage detection circuit 22 above. These details will not be repeated here.

[0173] S202. When the first voltage detection signal is equal to the second voltage detection signal and the voltage threshold, it is determined that there is no spark discharge phenomenon in the plug and no tripping phenomenon in the temperature limiter.

[0174] In this embodiment, when both the first thermal circuit breaker K1 and the second thermal circuit breaker K2 are closed, the first voltage detection signal VD1 and the second voltage detection signal VD2 received by the control circuit 24 are equal to the voltage threshold V, meaning that neither the first voltage detection signal VD1 nor the second voltage detection signal VD2 exhibits fluctuations. The control circuit 24 determines that there is no spark discharge at the plug 12 and no tripping of the temperature limiter 14 at this time.

[0175] S203. When the second voltage detection signal is equal to the first voltage detection signal and the second voltage detection signal is less than the voltage threshold, it is determined that there is a spark discharge phenomenon in the plug and the temperature limiter does not trip.

[0176] In this embodiment of the application, when the first thermal circuit breaker K1 is open and the second thermal circuit breaker K2 is closed, the second voltage detection signal VD2 received by the control circuit 24 is equal to the first voltage detection signal VD1, and the second voltage detection signal VD2 is less than the voltage threshold V. The control circuit 24 determines that there is a spark discharge phenomenon in the plug 12 and that there is no tripping phenomenon in the temperature limiter 14.

[0177] S204. When the second voltage detection signal is less than the first voltage detection signal and the first voltage detection signal is equal to the voltage threshold, it is determined that there is no spark discharge phenomenon in the plug and the temperature limiter trips.

[0178] In this embodiment of the application, when the first thermal circuit breaker K1 is closed and the second thermal circuit breaker K2 is open, the second voltage detection signal VD2 received by the control circuit 24 is less than the first voltage detection signal VD1, and the first voltage detection signal VD1 is equal to the voltage threshold V. The control circuit 24 determines that there is no spark discharge phenomenon in the plug 12 and that the temperature limiter 14 trips.

[0179] S205. When the second voltage detection signal is less than the first voltage detection signal and the first voltage detection signal is less than the voltage threshold, it is determined that there is a spark discharge phenomenon in the plug and the temperature limiter trips.

[0180] In this embodiment of the application, when both the first thermal circuit breaker K1 and the second thermal circuit breaker K2 are open, the second voltage detection signal VD2 received by the control circuit 24 is less than the first voltage detection signal VD1, and the first voltage detection signal VD1 is less than the voltage threshold V. The control circuit 24 determines that there is a spark discharge phenomenon in the plug 12 and that the temperature limiter 14 trips.

[0181] Correspondingly, when either the first thermal circuit breaker K1 or the second thermal circuit breaker K1 is open, and the electrical load 13 is in operation, there is a significant difference between the first voltage detection signal VD1 and the second voltage detection signal VD2, collected and output to the control circuit 24 by the first voltage detection circuit 23 and the second voltage detection circuit 25, and the preset voltage threshold V. This allows the control circuit 24 to easily distinguish between the first voltage detection signal VD1, the second voltage detection signal VD2, and the voltage threshold V, thereby determining whether there is a spark discharge phenomenon in the plug 12 and whether the temperature limiter 14 has tripped. In other words, by comparing the first voltage detection signal VD1, the second voltage detection signal VD2, and the voltage threshold V, the control circuit 24 can accurately determine whether there is a spark discharge phenomenon in the plug 12 and whether the temperature limiter 14 has tripped. By comparing the three voltage values, the risk of false alarms can be avoided, resulting in high detection reliability and accuracy.

[0182] Understandably, this detection method can detect not only the spark discharge phenomenon of the plug 12 based on the first voltage detection signal VD1, but also the tripping phenomenon of the temperature limiter 14 based on the second voltage detection signal VD2. That is, this detection method can achieve dual detection, thereby improving detection reliability and accuracy. Secondly, the control circuit 24 detects the spark discharge phenomenon of the plug 12 through the first thermal circuit breaker K1, the first resistor R1, and the first voltage detection signal VD1 corresponding to the first voltage detection circuit 22. Simultaneously, it detects the tripping phenomenon of the temperature limiter 14 through the second thermal circuit breaker K2, the second resistor R2, and the second voltage detection signal VD2 corresponding to the second voltage detection circuit 25. In other words, the control circuit 24 detects both the plug 12 and the temperature limiter 14 through two different voltage detection signals, avoiding the risk of false alarms when using the same voltage detection signal, further improving detection accuracy and reliability.

[0183] In the accompanying drawings of this embodiment, the same or similar reference numerals correspond to the same or similar components. In the description of this application, it should be understood that if terms such as "upper," "lower," "left," "right," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the drawings, they are only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, the terms used to describe positional relationships in the drawings are only for illustrative purposes and should not be construed as limiting this application. For those skilled in the art, the specific meaning of the above terms can be understood according to the specific circumstances.

[0184] The above description is merely a preferred embodiment of this application and is not intended to limit this application. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of this application should be included within the protection scope of this application.

Claims

1. A detection system applied to a household appliance, said household appliance including an electrical load and a plug, characterized in that, The detection system includes: A power supply circuit, comprising a neutral wire and a live wire, wherein the neutral wire and the live wire are both connected to the plug and the electrical load, and the neutral wire and the live wire are used to supply power to the electrical load; A first thermal circuit breaker is connected in series with the neutral wire or the live wire; The first resistor is connected in parallel with the first thermal circuit breaker, and both are disposed inside the plug; A first voltage detection circuit is connected to the output terminal of the neutral wire or the live wire connected in series with the first thermal circuit breaker. A power conversion circuit, the power conversion circuit being connected to the live wire; and, The control circuit is connected to the neutral wire, the first voltage detection circuit, the electrical load, and the power conversion circuit. The control circuit is used to control the electrical load to run for a preset time after power-on. The first voltage detection circuit is used to acquire the corresponding first voltage detection signal and output it to the control circuit. The control circuit is used to determine whether there is a spark discharge phenomenon in the plug based on the first voltage detection signal.

2. The detection system according to claim 1, characterized in that, The control circuit has a preset voltage threshold. When the first voltage detection signal is equal to the voltage threshold, the control circuit determines that there is no spark discharge phenomenon in the plug. When the first voltage detection signal is not equal to the voltage threshold, the control circuit determines that there is a spark discharge phenomenon in the plug.

3. The detection system according to claim 2, characterized in that, The household appliance also includes a thermostat, which is connected to the neutral wire and the live wire. The detection system also includes: The second thermal circuit breaker is connected in series with the neutral wire or the live wire and is located between the first thermal circuit breaker and the power conversion circuit. A second resistor, which is connected in parallel with the second thermal circuit breaker and is also located within the temperature limiter; and, The second voltage detection circuit is connected to the output terminal of the neutral wire or the live wire connected in series with the second thermal circuit breaker. After the electrical load has been running for the preset time, the second voltage detection circuit is used to acquire the corresponding second voltage detection signal and output it to the control circuit. The control circuit is also used to determine whether the temperature limiter has tripped based on the second voltage detection signal.

4. The detection system according to claim 3, characterized in that, When the first voltage detection signal is equal to the second voltage detection signal and the voltage threshold, the control circuit determines that there is no spark discharge phenomenon in the plug and no tripping phenomenon in the temperature limiter. When the second voltage detection signal is equal to the first voltage detection signal and the second voltage detection signal is less than the voltage threshold, the control circuit determines that there is a spark discharge phenomenon in the plug and that the temperature limiter does not trip. When the second voltage detection signal is less than the first voltage detection signal and the first voltage detection signal is equal to the voltage threshold, the control circuit determines that there is no spark discharge phenomenon in the plug and that the temperature limiter trips. When the second voltage detection signal is less than the first voltage detection signal, and the first voltage detection signal is less than the voltage threshold, the control circuit determines that there is a spark discharge phenomenon in the plug and that the temperature limiter trips.

5. The detection system according to claim 1, characterized in that, The power conversion circuit includes: An AC-DC converter is provided, wherein the input terminal of the AC-DC converter is connected to the live wire, and the output terminal of the AC-DC converter is connected to the control circuit. The AC-DC converter is used to convert the AC power provided by the live wire into DC power and output it to the control circuit.

6. The detection system according to claim 5, characterized in that, The power conversion circuit also includes: A first rectifier module is connected to the live wire; A first filtering module is connected to the first rectifier module, the neutral wire, and the input terminal of the AC-DC converter; and, The second filtering module is connected to the output terminal of the AC-DC converter, the neutral wire, and the control circuit, and is connected to the power supply voltage.

7. The detection system according to claim 6, characterized in that, The first rectifier module includes a first diode, and the first filter module includes a first capacitor, an inductor, and a second capacitor; The positive terminal of the first diode is connected to the live wire, the negative terminal of the first diode is connected to the first plate of the first capacitor and one end of the inductor, the second plate of the first capacitor is connected to the neutral wire, the other end of the inductor is connected to the first plate of the second capacitor and the input terminal of the AC-DC converter, and the second plate of the second capacitor is connected to the neutral wire.

8. The detection system according to any one of claims 1-7, characterized in that, The first voltage detection circuit includes: A voltage divider module, wherein the first terminal of the voltage divider module is connected to the output terminal of the neutral wire or the live wire connected in series with the first thermal circuit breaker, and the second terminal of the voltage divider module is grounded; and, A current limiting module, one end of which is connected to the third terminal of the voltage divider module, and the other end of which is connected to the control circuit.

9. The detection system according to claim 8, characterized in that, The voltage divider module includes multiple third resistors connected in series; Wherein, the end of the first third resistor that is not connected to the third resistor serves as the first terminal of the voltage divider module and is connected to the output terminal of the neutral wire or the live wire connected in series with the first thermal circuit breaker; the end of the last third resistor that is connected to the adjacent third resistor serves as the third terminal of the voltage divider module and is connected to one terminal of the current limiting module; the other end of the last third resistor that is not connected to the third resistor serves as the second terminal of the voltage divider module and is grounded. And / or, The current limiting module includes a fourth resistor. One end of the fourth resistor serves as one end of the current limiting module and is connected to the third end of the voltage divider module. The other end of the fourth resistor serves as the other end of the current limiting module and is connected to the control circuit.

10. The detection system according to claim 8, characterized in that, The first voltage detection circuit further includes: A second rectifier module, one end of which is connected to the output terminal of the neutral or live wire connected in series with the first thermal circuit breaker, and the other end of which is connected to the first terminal of the voltage divider module; and, A clamping module, one end of which is connected to the third terminal of the voltage divider module and one end of the current limiting module, and the other end of which is connected to the power supply voltage; Specifically, the clamping module is turned on when the voltage output by the voltage divider module is greater than or equal to the rated voltage of the clamping module.

11. The detection system according to claim 10, characterized in that, The second rectifier module includes a second diode. The positive terminal of the second diode serves as one end of the second rectifier module and is connected to the output terminal of the neutral wire or the live wire connected in series with the first thermal circuit breaker. The negative terminal of the second diode serves as the other end of the second rectifier module and is connected to the first end of the voltage divider module. And / or, The clamping module includes a third diode. The positive terminal of the third diode serves as one end of the clamping module and is connected to the third terminal of the voltage divider module and one end of the current limiting module. The negative terminal of the third diode serves as the other end of the clamping module and is connected to the power supply voltage.

12. The detection system according to claim 10, characterized in that, The first voltage detection circuit further includes: A third filtering module, one end of which is connected to one end of the clamping module, the third end of the voltage divider module, and one end of the current limiting module; the other end of the third filtering module is connected to a common ground with the second end of the voltage divider module; and, The fourth filtering module has one end connected to the other end of the current limiting module and the control circuit, and the other end of the fourth filtering module is grounded.

13. The detection system according to claim 12, characterized in that, The third filtering module includes a third capacitor. The first plate of the third capacitor serves as one end of the third filtering module and is connected to one end of the clamping module, the third end of the voltage divider module, and one end of the current limiting module. The second plate of the third capacitor serves as the other end of the third filtering module and is connected to the second end of the voltage divider module. And / or, The fourth filtering module includes a fourth capacitor. The first plate of the fourth capacitor serves as one end of the fourth filtering module and is connected to the other end of the current limiting module and the control circuit. The second plate of the fourth capacitor serves as the other end of the fourth filtering module and is grounded.

14. A household appliance, characterized in that, include: The detection system as described in any one of claims 1 to 13, wherein the electrical load includes a fan and / or a heating element; as well as, The plug is connected to the live wire and the neutral wire, and the first thermal circuit breaker and the first resistor are both disposed inside the plug.

15. The household appliance according to claim 14, characterized in that, The household appliances also include: A temperature limiter is connected to the neutral wire and the live wire.

16. A method for testing household appliances, characterized in that, Applied to any household appliance as described in any one of claims 14 to 15, the method comprises: The household appliance is powered on; Preset operating time for electrical loads; Acquire the first voltage detection signal; When the first voltage detection signal is equal to the voltage threshold, it is determined that there is no spark discharge phenomenon in the plug; When the first voltage detection signal is not equal to the voltage threshold, it is determined that the plug has a spark discharge phenomenon.

17. The detection method according to claim 16, characterized in that, After the controlled electrical load has been running for a preset period of time, the method further includes: Acquire the second voltage detection signal; When the first voltage detection signal is equal to the second voltage detection signal and the voltage threshold, it is determined that there is no spark discharge phenomenon in the plug and no tripping phenomenon in the temperature limiter. When the second voltage detection signal is equal to the first voltage detection signal and the second voltage detection signal is less than the voltage threshold, it is determined that there is a spark discharge phenomenon in the plug and the temperature limiter does not trip. When the second voltage detection signal is less than the first voltage detection signal and the first voltage detection signal is equal to the voltage threshold, it is determined that there is no spark discharge phenomenon in the plug and the temperature limiter trips. When the second voltage detection signal is less than the first voltage detection signal, and the first voltage detection signal is less than the voltage threshold, it is determined that the plug has a spark discharge phenomenon and the temperature limiter has a tripping phenomenon.

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