Water inlet valve control circuit for washing machine and washing machine

Abstract

The application discloses a washing machine water inlet valve control circuit and a washing machine. The washing machine water inlet valve control circuit comprises: a water inlet valve driving circuit, which has a relay; a surge protection circuit, which is connected to the input end of the relay of the water inlet valve driving circuit; and a door lock power supply circuit, which is connected to the water inlet valve power supply positive pole of the water inlet valve driving circuit and the output end of the relay. When the surge protection circuit fails, the door lock power supply circuit is disconnected with the failure of the surge protection circuit. The application can disconnect the door lock power supply circuit when the surge protection circuit fails, thereby cutting off the power supply of the water inlet valve, preventing the water inlet valve from being mistakenly started, and greatly reducing the water leakage rate of the washing machine in the standby state.

Description

Technical Field

[0001] This application relates to the field of washing machine technology, and more specifically, to a washing machine inlet valve control circuit and a washing machine. Background Technology

[0002] There is a close electrical and logical connection between the washing machine's water inlet valve and door lock. This design aims to ensure the safety and sequence of the washing process. Typically, when the washing machine starts, the control system will first check the door lock status. If the washing machine door is not closed or locked, the door lock switch is in the open state, and the control system will cut off the drive circuit of the water inlet valve, causing the water inlet valve to be unable to open. The purpose of this safety interlock mechanism is to prevent users from accidentally opening the door during the washing process, which could lead to water splashing or electric shock risks, while also preventing the washing machine from leaking water when the door is not closed.

[0003] Currently, when washing machines are in standby mode, surges in the power grid can easily cause the inlet valve to activate erroneously, leading to water leaks, property damage, and safety hazards. The main reason for this is that existing surge protection features primarily focus on the relay itself or the MCU control module, failing to cover the inlet valve drive circuit. Simultaneously, the door lock relies on software logic, which cannot disconnect the power supply circuit when the relay fails, allowing the inlet valve to remain powered and erroneously activate. This causes the safety interlock mechanism to fail, resulting in a higher leakage rate in the washing machine's standby mode. Utility Model Content

[0004] The purpose of this application is to provide a washing machine inlet valve control circuit and a washing machine. The washing machine inlet valve control circuit can disconnect the door lock power supply circuit when the surge protection circuit fails, thereby cutting off the power supply to the inlet valve, preventing the inlet valve from being accidentally started, and greatly reducing the water leakage rate of the washing machine in standby mode.

[0005] To achieve the above objectives, in a first aspect, this application provides a washing machine inlet valve control circuit, comprising:

[0006] A water inlet valve drive circuit, wherein the water inlet valve drive circuit has a relay;

[0007] A surge protection circuit, wherein the surge protection circuit is connected to the input terminal of the relay of the water inlet valve drive circuit;

[0008] A door lock power supply circuit, wherein the door lock power supply circuit is connected to the positive terminal of the water inlet valve power supply and the output terminal of the relay of the water inlet valve drive circuit;

[0009] When the surge protection circuit fails, the door lock power supply circuit is disconnected along with the surge protection circuit.

[0010] In the implementation of the above technical solution, the surge protection circuit of the washing machine's water inlet valve control circuit is connected to the input terminal of the relay in the water inlet valve drive circuit, and the door lock power supply circuit is connected to the positive terminal of the water inlet valve power supply and the output terminal of the relay in the water inlet valve drive circuit. When the surge protection circuit fails, the relay hardware fails (such as the relay contacts being welded), causing the door lock power supply circuit to disconnect, and the door lock to be independently powered off, thereby cutting off the power supply to the water inlet valve and preventing the water inlet valve from being accidentally started, greatly reducing the water leakage rate of the washing machine in standby mode. The washing machine's water inlet valve control circuit constructs a dynamic safety closed loop of "surge protection failure → automatic door lock power-off", which completely solves the technical contradiction of "surge protection is effective but the safety interlock mechanism fails", providing a new technical paradigm for washing machine safety control and possessing significant application and industrial value.

[0011] In a preferred embodiment of this application, the door lock power supply circuit includes a door lock switch, the door lock switch having two normally closed contacts, namely a main contact A and a backup contact B.

[0012] The main contact A is connected to the positive terminal of the water inlet valve power supply and the output terminal of the relay in the water inlet valve drive circuit, and the backup contact B is connected in series with the main contact A in the electrical path.

[0013] In the implementation of the above technical solution, the door lock power supply circuit is directly integrated into the positive power supply path of the water inlet valve through a physical hard series connection of the two normally closed contacts (main contact A and backup contact B) of the door lock switch. This enables physical power cut-off at the hardware level when the surge protection circuit fails. This design concept of door lock power supply circuit abandons the traditional door lock software control logic, requires no software intervention, and ensures that the door lock can still be independently powered off when the relay fails (such as when the relay contacts are welded), which significantly improves safety and reliability.

[0014] In a preferred embodiment of this application, the backup contact B and the main contact A are connected in series in the electrical path, in the following manner:

[0015] The main contact A is routed on the top layer of the PCB, and the backup contact B is routed on the bottom layer of the PCB. The main contact A and the backup contact B are electrically connected through vias.

[0016] In the implementation of the above technical solution, the main contact A is routed on the top layer of the PCB, and the backup contact B is routed on the bottom layer of the PCB. The main contact A and the backup contact B are electrically connected through vias, so that the two normally closed contacts of the door lock switch are connected in series on the electrical path. This allows the backup contact B to be routed in series with the main contact A but independently (using different PCB routing layers), avoiding the risk of contact adhesion and further improving safety and reliability.

[0017] In a preferred embodiment of this application, the surge protection circuit includes a voltage divider branch and a surge protector.

[0018] The voltage divider branch is connected to the input terminal of the relay of the inlet valve drive circuit and the surge protector, and the voltage divider branch and the surge protector are connected in parallel.

[0019] In the implementation of the above technical solution, when subjected to power grid surge impact, the surge protector can clamp the voltage to a specific voltage value under the power grid surge impact, while the voltage divider branch can reduce the load of the surge protector and absorb part of the power grid surge energy through voltage division. The two work together to effectively suppress the power grid surge voltage. For example, the original effective value of 788V is suppressed to 540V, which not only protects the relay from overvoltage damage, but also avoids the surge protector from overload breakdown, and can better ensure the safety and reliability of the water inlet valve drive circuit.

[0020] In a preferred embodiment of this application, the voltage divider branch is a resistor-capacitor voltage divider branch.

[0021] In the implementation of the above technical solution, the voltage divider branch adopts the RC voltage divider branch. The RC voltage divider branch can play a good voltage dividing role, thereby effectively reducing the load of the surge protector and absorbing part of the power grid surge energy.

[0022] In a preferred embodiment of this application, the RC voltage divider branch includes a voltage divider resistor and a voltage divider capacitor, wherein the voltage divider resistor and the voltage divider capacitor are connected in series and are connected in parallel with the surge protector.

[0023] In the implementation of the above technical solution, although the structure of this RC voltage divider branch is simple, it is actually a targeted design for surge protection. It can avoid the mechanism of the RC voltage divider branch being too complex and redundant, and can ensure that the RC voltage divider branch has a good voltage dividing effect and voltage dividing function.

[0024] In a preferred embodiment of this application, the voltage divider resistor is a 100Ω / 1W metal film resistor, and the voltage divider capacitor is a 0.1μF / 250V high-voltage ceramic capacitor.

[0025] In the implementation of the above technical solution, the use of the above-mentioned specific components for the voltage dividing resistor and voltage dividing capacitor enables the RC voltage dividing branch to achieve a more ideal voltage dividing effect and voltage dividing function, thereby better reducing the load of the surge protector and absorbing some of the power grid surge energy.

[0026] In a preferred embodiment of this application, the surge protector employs a transient voltage suppression diode.

[0027] In the implementation of the above technical solution, the surge protector adopts transient voltage suppression diodes. Transient voltage suppression diodes can quickly conduct when the voltage is abnormal, limiting the overvoltage to a safe range, and have good voltage suppression effect and performance.

[0028] In a preferred embodiment of this application, the clamping voltage of the transient voltage suppressor diode is 10V.

[0029] In the implementation of the above technical solution, the clamping voltage of the transient voltage suppression diode is 10V. 10V is a reasonable choice based on the relay withstand voltage, the coordination of the voltage divider branch and cost optimization, and it has high reliability.

[0030] Secondly, this application provides a washing machine equipped with the aforementioned washing machine inlet valve control circuit.

[0031] This application discloses a water inlet valve control circuit for a washing machine and a washing machine, which, compared with the prior art, have at least the following advantages:

[0032] The washing machine inlet valve control circuit of this application includes an inlet valve drive circuit, a surge protection circuit, and a door lock power supply circuit. The inlet valve drive circuit includes a relay. The surge protection circuit is connected to the input terminal of the relay in the inlet valve drive circuit. The door lock power supply circuit is connected to the positive terminal of the inlet valve power supply and the output terminal of the relay in the inlet valve drive circuit. When the surge protection circuit fails, the relay hardware fails (e.g., the relay contacts are welded), causing the door lock power supply circuit to disconnect. The door lock can then be independently powered off, thereby cutting off the power supply to the inlet valve and preventing accidental activation of the inlet valve. This significantly reduces the leakage rate of the washing machine in standby mode. This washing machine inlet valve control circuit constructs a dynamic safety closed loop of "surge protection failure → automatic door lock power-off," completely resolving the technical contradiction of "effective surge protection but failed safety interlock mechanism." It provides a new technical paradigm for washing machine safety control and has significant application and industrial value.

[0033] The washing machine of this application is equipped with the aforementioned washing machine inlet valve control circuit, which can disconnect the door lock power supply circuit when the surge protection circuit fails, allowing the door lock to be independently powered off, thereby cutting off the power supply to the inlet valve, preventing the inlet valve from being accidentally started, greatly reducing the water leakage rate of the washing machine in standby mode, and improving the practicality and user experience of the washing machine. Attached Figure Description

[0034] To more clearly illustrate the technical solutions of the embodiments of this application, the accompanying drawings used in the embodiments of this application will be briefly introduced below. It should be understood that the following drawings only show some embodiments of this application and should not be regarded as a limitation of the scope. For those skilled in the art, other related drawings can be obtained based on these drawings without creative effort.

[0035] Figure 1 This is a first structural block diagram of the washing machine water inlet valve control circuit provided in the embodiments of this application;

[0036] Figure 2 This is a second structural block diagram of the washing machine water inlet valve control circuit provided in the embodiments of this application;

[0037] Figure 3 This is one of the electrical schematic diagrams of the door lock power supply circuit of the washing machine water inlet valve control circuit provided in the embodiments of this application;

[0038] Figure 4 This is the second electrical schematic diagram of the door lock power supply circuit of the washing machine water inlet valve control circuit provided in the embodiments of this application.

[0039] Figure reference numerals: 11. Inlet valve drive circuit; 12. Surge protection circuit; 121. Voltage divider branch; 122. Surge protector; 13. Door lock power supply circuit. Detailed Implementation

[0040] The technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, and not all embodiments. The components of the embodiments of this application described and shown in the accompanying drawings can be arranged and designed in various different configurations. Therefore, the following detailed description of the embodiments of this application provided in the accompanying drawings is not intended to limit the scope of the claimed application, but merely represents selected embodiments of this application. All other embodiments obtained by those skilled in the art based on the embodiments of this application without inventive effort are within the scope of protection of this application.

[0041] In this application, the terms "upper," "lower," "left," "right," "front," "rear," "top," "bottom," "inner," "outer," "middle," "vertical," "horizontal," "lateral," and "longitudinal" indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. These terms are primarily for the purpose of better describing this application and its embodiments, and are not intended to limit the indicated device, element, or component to having a specific orientation, or to be constructed and operated in a specific orientation.

[0042] Furthermore, in addition to indicating location or positional relationship, some of the aforementioned terms may also have other meanings. For example, the term "above" may also be used in some cases to indicate a certain dependency or connection relationship. Those skilled in the art can understand the specific meaning of these terms in this application based on the specific circumstances.

[0043] Furthermore, the terms "installation," "setup," "equipped with," "connection," and "linked" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral structure; they can refer to a mechanical connection or a point connection; they can refer to a direct connection or an indirect connection through an intermediate medium, or an internal connection between two devices, components, or parts. Those skilled in the art can understand the specific meaning of these terms in this application based on the specific circumstances.

[0044] Furthermore, the terms "first," "second," etc., are primarily used to distinguish different devices, elements, or components (which may be the same or different in specific type and construction), and are not intended to indicate or imply the relative importance or quantity of the indicated devices, elements, or components. Unless otherwise stated, "a plurality of" means two or more.

[0045] Currently, when washing machines are in standby mode, surges in the power grid can easily cause the inlet valve to activate erroneously, leading to water leaks, property damage, and safety hazards. The main reason for this is that existing surge protection features primarily focus on the relay itself or the MCU control module, failing to cover the inlet valve drive circuit. Simultaneously, the door lock relies on software logic, which cannot disconnect the power supply circuit when the relay fails, allowing the inlet valve to remain powered and erroneously activate. This causes the safety interlock mechanism to fail, resulting in a higher leakage rate in the washing machine's standby mode.

[0046] To address the problems in the prior art, this application provides a washing machine inlet valve control circuit and a washing machine. The washing machine inlet valve control circuit can disconnect the door lock power supply circuit when the surge protection circuit fails, thereby cutting off the power supply to the inlet valve, preventing the inlet valve from being accidentally started, and greatly reducing the water leakage rate of the washing machine in standby mode.

[0047] Example 1

[0048] See Figure 1 , Figure 1 This is a structural block diagram of the washing machine water inlet valve control circuit provided in the embodiments of this application.

[0049] The washing machine inlet valve control circuit of this application embodiment includes:

[0050] Inlet valve drive circuit 11, the inlet valve drive circuit 11 has a relay;

[0051] Surge protection circuit 12, which is connected to the input terminal of the relay of the inlet valve drive circuit 11;

[0052] The door lock power supply circuit 13 is connected to the positive terminal of the water inlet valve power supply and the output terminal of the relay in the water inlet valve drive circuit 11.

[0053] When surge protection circuit 12 fails, door lock power supply circuit 13 is disconnected along with surge protection circuit 12.

[0054] In this embodiment, the washing machine inlet valve control circuit is used to control the power supply to and from the inlet valve.

[0055] In this embodiment, the water inlet valve drive circuit 11 is the core circuit that controls the action of the water inlet solenoid valve of the washing machine. The water inlet valve drive circuit 11 has a relay. The water inlet valve drive circuit 11 can adopt the structure of the conventional water inlet valve drive circuit 11 of the washing machine in the prior art. Here, the other circuit structures of the conventional water inlet valve drive circuit 11 of the washing machine in the prior art will not be described in detail.

[0056] The surge protection circuit 12 has a surge protector. The surge protection circuit 12 is connected to the input terminal of the relay of the water inlet valve drive circuit 11. The core function of the surge protection circuit 12 is to suppress transient overvoltage, prevent voltage surges caused by lightning strikes, power grid fluctuations or equipment start-up and shutdown from damaging the internal electronic components of the washing machine, extend the equipment life and ensure safe use.

[0057] The door lock power supply circuit 13 is a key circuit that ensures the washing machine door is safely closed and locked, and provides protection when powered on. The core components of the door lock power supply circuit 13 include an electric door lock, a power switch, a control board (or program controller), a door hook, and a contact switch. In this embodiment, the door lock power supply circuit 13 is connected to the positive terminal of the water inlet valve power supply of the water inlet valve drive circuit 11 and the output terminal of the relay.

[0058] In this embodiment of the washing machine inlet valve control circuit, the surge protection circuit 12 is connected to the input terminal of the relay in the inlet valve drive circuit 11, and the door lock power supply circuit 13 is connected to the positive terminal of the inlet valve power supply and the output terminal of the relay in the inlet valve drive circuit 11. Under this circuit structure, when the surge protection circuit 12 fails (for example, the surge protector is broken down), the relay hardware fails (such as the relay contacts are welded), causing the door lock power supply circuit 13 to disconnect, and the door lock can be independently de-energized, thereby cutting off the power supply to the inlet valve and preventing the inlet valve from being accidentally started, greatly reducing the leakage rate of the washing machine in standby mode. This washing machine inlet valve control circuit constructs a dynamic safety closed loop of "surge protection failure → automatic door lock power-off", which completely solves the technical contradiction of "surge protection is effective but the safety interlock mechanism fails", providing a new technical paradigm for washing machine safety control and having significant application and industrial value.

[0059] Example 2

[0060] See Figure 2 , Figure 2 This is a structural block diagram of the washing machine water inlet valve control circuit provided in the embodiments of this application.

[0061] Based on the above embodiment one, the surge protection circuit 12 of the washing machine inlet valve control circuit of this application embodiment includes a voltage divider branch 121 and a surge protector 122.

[0062] The voltage divider branch 121 and the surge protector 122 are connected to the input terminal of the relay of the inlet valve drive circuit 11, and the voltage divider branch 121 and the surge protector 122 are connected in parallel.

[0063] In this embodiment, the voltage divider branch 121 is used to divide the voltage and absorb part of the power grid surge energy; the surge protection device (SPD) 122 is a device used to protect power systems and electronic equipment from the effects of lightning and overvoltage. Its core function is to limit the instantaneous overvoltage that enters the power line or signal transmission line to the range that the equipment or system can withstand, or to discharge the powerful lightning current into the ground, thereby protecting the protected equipment or system from damage caused by the impact.

[0064] In the above structure, when subjected to a power grid surge, the surge protector 122 can clamp the voltage to a specific voltage value under the power grid surge impact, while the voltage divider branch 121 can reduce the load of the surge protector 122 and absorb part of the power grid surge energy through voltage division. The two work together to effectively suppress the power grid surge voltage. For example, the original effective value of 788V is suppressed to 540V, which not only protects the relay from overvoltage damage, but also avoids the surge protector 122 from overload breakdown, and can better ensure the safety and reliability of the water inlet valve drive circuit 11.

[0065] Example 3

[0066] See Figure 2 Based on the above embodiment 2, the water inlet valve control circuit of the washing machine in this embodiment adopts a resistive-capacitive voltage divider branch 121.

[0067] Specifically, a resistor-capacitor voltage divider is a circuit that uses a combination of resistors and capacitors to achieve voltage division. It combines the stability of resistor voltage division with the frequency response characteristics of capacitor voltage division. A resistor-capacitor voltage divider is usually composed of a resistor (R) and a capacitor (C) connected in series. The input voltage is applied across the two ends of the series circuit, and the output voltage is taken from the two ends of the resistor or capacitor.

[0068] It should be noted that in other embodiments, the voltage divider branch 121 can also be implemented using other voltage divider circuits. Here, other possible voltage divider circuits will not be listed.

[0069] In the above structure, the voltage divider branch 121 adopts a resistive-capacitive voltage divider branch, which can play a good role in voltage division, thereby effectively reducing the load of surge protector 122 and absorbing part of the power grid surge energy.

[0070] Furthermore, in this embodiment, the RC voltage divider branch includes a voltage divider resistor and a voltage divider capacitor, which are connected in series and in parallel with the surge protector 122.

[0071] Understandably, in other embodiments, the RC voltage divider branch can also be implemented using other RC voltage divider circuit structures, that is, the number of voltage divider resistors and voltage divider capacitors used can be more than one. Here, other RC voltage divider circuits that can be used will not be listed.

[0072] In the above structure, although the RC voltage divider branch has a simple structure, it is actually a targeted design for surge protection. It can avoid the mechanism of the RC voltage divider branch being too complex and redundant, while ensuring that the RC voltage divider branch has a good voltage dividing effect and function.

[0073] Preferably, in this embodiment, the voltage divider resistor is a 100Ω / 1W metal film resistor, and the voltage divider capacitor is a 0.1μF / 250V high-voltage ceramic capacitor.

[0074] By using the aforementioned specific components for the voltage divider resistors and capacitors, the voltage divider branch can achieve a more ideal voltage dividing effect and function, thereby better reducing the load on surge protector 122 and absorbing some of the power grid surge energy.

[0075] Furthermore, in this embodiment, the surge protector 122 employs a transient voltage suppression diode.

[0076] Specifically, a transient voltage suppressor diode (TVS) is an electronic component used for circuit protection, mainly used to suppress transient overvoltages (such as lightning strikes, power grid surges, etc.) and protect subsequent circuits from damage. The introduction of the transient voltage suppressor diode (TVS) enables the surge protection circuit 12 to effectively suppress voltage peaks during power grid surge (e.g., 4kV) tests. At the same time, through cooperation with the RC voltage divider branch, it avoids overload breakdown of the transient voltage suppressor diode (TVS) and ensures that the relay operates reliably in surge environments.

[0077] For example, a transient voltage suppressor diode (TVS) of the SMBJ10A type can be used.

[0078] In the above structure, the surge protector 122 adopts a transient voltage suppression diode. The transient voltage suppression diode can quickly conduct when the voltage is abnormal. The response time of the transient voltage suppression diode is <1ns, which limits the overvoltage within a safe range and has a good voltage suppression effect and performance.

[0079] It should be noted that in other embodiments, surge protector 122 may also be other surge protectors 122. Here, other surge protectors 122 that can be used will not be listed.

[0080] Preferably, in this embodiment, the clamping voltage of the transient voltage suppression diode is 10V.

[0081] Specifically, the clamping voltage of the transient voltage suppressor diode (TVS) is not fixed at 10V, but exists in a voltage range (such as 9.5V-10.5V), depending on factors such as device model, current and temperature. In this embodiment, 10V is a reasonable choice based on relay withstand voltage, RC voltage divider branch coordination and cost optimization. However, in practical applications, the clamping voltage can be adjusted according to specific needs, and its reliability can be verified through testing.

[0082] In the above structure, the clamping voltage of the transient voltage suppressor diode is 10V. 10V is a reasonable choice based on the relay withstand voltage, the coordination of the voltage divider branch 121, and cost optimization, and its high reliability has been verified through testing.

[0083] Example 4

[0084] See Figure 3 and Figure 4 , Figure 3 and Figure 4 This is a schematic diagram of the electrical principle of the door lock power supply circuit 13 of the washing machine water inlet valve control circuit provided in this embodiment of the application.

[0085] Based on any of the embodiments one to three above, the washing machine inlet valve control circuit and the door lock power supply circuit 13 of this embodiment include a door lock switch. The door lock switch has two normally closed contacts, namely the main contact A and the backup contact B.

[0086] Among them, the main contact A is connected to the positive terminal of the water inlet valve power supply and the output terminal of the relay in the water inlet valve drive circuit 11, and the backup contact B is connected in series with the main contact A in the electrical path.

[0087] In the above structure, the door lock power supply circuit 13 is directly integrated into the positive power supply path of the water inlet valve through the physical hard series connection of the two normally closed contacts (main contact A and backup contact B) of the door lock switch. It can realize physical power cut-off at the hardware level when the surge protection circuit 12 fails. This design concept of door lock power supply circuit 13 abandons the traditional door lock software control logic, without software intervention, and ensures that when the relay fails (such as the relay contact welding), the door lock can still be independently powered off (if any contact of the main contact A and backup contact B is stuck, the other contact can still be disconnected), which significantly improves safety and reliability.

[0088] After testing and verification, it was found that when the relay output is continuously at a high level (simulating a fault state), the water inlet valve of the washing machine will not have water entering the valve for 24 hours after the control circuit is triggered, the false start rate is 0%, and the leakage rate is 0%.

[0089] Furthermore, in this embodiment, the backup contact B and the main contact A are connected in series in the electrical path, in the following manner:

[0090] The main contact A is routed on the top layer of the PCB, and the backup contact B is routed on the bottom layer of the PCB. The main contact A and the backup contact B are electrically connected through vias.

[0091] The PCB consists of a top layer and a bottom layer. The main contact A and the backup contact B are electrically connected through vias to form a dual-contact redundant path, achieving physical isolation.

[0092] Specifically, for an explanation of how the backup contact B and the main contact A are connected in series in the electrical path, please refer to the following table:

[0093]

[0094] In the above structure, the main contact A is routed on the top layer of the PCB, and the backup contact B is routed on the bottom layer of the PCB. The main contact A and the backup contact B are electrically connected through vias, so that the two normally closed contacts of the door lock switch are connected in series on the electrical path. This allows the backup contact B to be routed in series with the main contact A but independently (using different PCB routing layers), avoiding the risk of contact sticking and further improving safety and reliability.

[0095] Example 5

[0096] See Figures 1 to 4 This application provides a washing machine that is equipped with a washing machine inlet valve control circuit of any one of the embodiments 1 to 4 described above.

[0097] The washing machine of this application embodiment is equipped with a washing machine inlet valve control circuit of any of the above embodiments one to four. When the surge protection circuit 12 fails, the door lock power supply circuit 13 is disconnected, the door lock can be independently de-energized, and the power supply to the inlet valve is cut off, preventing the inlet valve from being accidentally started. This greatly reduces the water leakage rate of the washing machine in standby mode and improves the practicality and user experience of the washing machine.

[0098] In all the above embodiments, "large" and "small" are relative terms, "more" and "less" are relative terms, and "upper" and "lower" are relative terms. The embodiments of this application will not elaborate further on the expression of such relative terms.

[0099] It should be understood that phrases such as "in one embodiment," "in this embodiment," "in this application embodiment," or "as an optional implementation" throughout the specification mean that a specific feature, structure, or characteristic related to an embodiment is included in at least one embodiment of this application. Therefore, phrases such as "in one embodiment," "in this embodiment," "in this application embodiment," or "as an optional implementation" appearing throughout the specification do not necessarily refer to the same embodiment. Furthermore, these specific features, structures, or characteristics can be combined in any suitable manner in one or more embodiments. Those skilled in the art should also understand that the embodiments described in the specification are all optional embodiments, and the actions and modules involved are not necessarily essential to this application.

[0100] In the various embodiments of this application, it should be understood that the sequence number of each process does not necessarily imply the order of execution. The execution order of each process should be determined by its function and internal logic, and should not constitute any limitation on the implementation process of the embodiments of this application.

[0101] The above description is merely a specific embodiment of this application, but the scope of protection of this application is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the scope of the technology disclosed in this application should be included within the scope of protection of this application. Therefore, the scope of protection of this application should be determined by the scope of protection of the claims.

Claims

1. A water inlet valve control circuit for a washing machine, characterized in that, include: A water inlet valve drive circuit, wherein the water inlet valve drive circuit has a relay; A surge protection circuit, wherein the surge protection circuit is connected to the input terminal of the relay of the water inlet valve drive circuit; A door lock power supply circuit, wherein the door lock power supply circuit is connected to the positive terminal of the water inlet valve power supply and the output terminal of the relay of the water inlet valve drive circuit; When the surge protection circuit fails, the door lock power supply circuit is disconnected along with the surge protection circuit.

2. The washing machine water inlet valve control circuit according to claim 1, characterized in that, The door lock power supply circuit includes a door lock switch, which has two normally closed contacts, namely, a main contact A and a backup contact B. The main contact A is connected to the positive terminal of the water inlet valve power supply and the output terminal of the relay in the water inlet valve drive circuit, and the backup contact B is connected in series with the main contact A in the electrical path.

3. The washing machine water inlet valve control circuit according to claim 2, characterized in that, The backup contact B and the main contact A are connected in series in the electrical path, in the following manner: The main contact A is routed on the top layer of the PCB, and the backup contact B is routed on the bottom layer of the PCB. The main contact A and the backup contact B are electrically connected through vias.

4. The washing machine water inlet valve control circuit according to claim 1, characterized in that, The surge protection circuit includes a voltage divider branch and a surge protector. The voltage divider branch is connected to the input terminal of the relay of the inlet valve drive circuit and the surge protector, and the voltage divider branch and the surge protector are connected in parallel.

5. The washing machine water inlet valve control circuit according to claim 4, characterized in that, The voltage divider branch adopts a resistor-capacitor voltage divider branch.

6. The washing machine water inlet valve control circuit according to claim 5, characterized in that, The RC voltage divider branch includes a voltage divider resistor and a voltage divider capacitor. The voltage divider resistor and the voltage divider capacitor are connected in series and in parallel with the surge protector.

7. The washing machine water inlet valve control circuit according to claim 6, characterized in that, The voltage divider resistor is a 100Ω / 1W metal film resistor, and the voltage divider capacitor is a 0.1μF / 250V high-voltage ceramic capacitor.

8. The washing machine water inlet valve control circuit according to any one of claims 4-7, characterized in that, The surge protector uses transient voltage suppression diodes.

9. The washing machine water inlet valve control circuit according to claim 8, characterized in that, The clamping voltage of the transient voltage suppressor diode is 10V.

10. A washing machine, characterized in that, The washing machine is equipped with a water inlet valve control circuit as described in any one of claims 1-9.

Images