Filter ground protection system and variable frequency washing machine

Abstract

The utility model provides a kind of filter ground's protection system and variable frequency washing machine, the system includes first protection module, second protection module and heating pipe, one end of first protection module is connected with firewire AC-L, the current input end of heating pipe is connected with the other end of first protection module, heating pipe is arranged between inner tub and outer tub of variable frequency washing machine, the shell of heating pipe is grounded, one end of second protection module is grounded, the other end of second protection module is arranged in filter;Through the protection system and variable frequency washing machine of filter ground of the utility model, the structure of system can be optimized, the stability and reliability of system are improved, the cost of system is reduced;Enhance the protection degree of system in the process of user use, and then improve the security and reliability of user use, improve the satisfaction of user.

Description

Technical Field

[0001] This utility model relates to the field of variable frequency washing machines, and more specifically, to a protection system for filter grounding and a variable frequency washing machine. Background Technology

[0002] With the rapid development of technology, washing machines have undergone diverse changes. Unlike traditional fixed-frequency washing machines that use AC induction motors and require repeated start-stop cycles to adjust washing intensity, leading to high power consumption, noise, and water consumption, inverter washing machines are becoming increasingly common. Because they use DC brushless motors or permanent magnet synchronous motors, they achieve stepless speed regulation, reducing mechanical impact. Therefore, compared to fixed-frequency washing machines, they save energy, reduce water flow impact, minimize wear and tear on clothes, and achieve noise reduction, water conservation, and energy saving.

[0003] However, in existing inverter washing machines, the grounding device's filter typically connects the grounding wire directly to a capacitor, causing a 110V voltage drop to be applied to the inner drum via the heater. If the user's home grounding is poor, the user may experience a tingling sensation. Therefore, researching ways to improve the stability and reliability of inverter washing machines during operation and avoid the impact of poor grounding on user safety is of great significance.

[0004] Patent publication number CN106887775A mentions a grounding detection and protection plug and a washing machine, including a plug body, a flexible tube, and a circuit board. The plug body has a cavity, the circuit board is placed inside the cavity, and the flexible tube is placed at the lower end of the plug body and communicates with the cavity. The circuit board has a detection circuit and a switch K. An inlet terminal is provided on the side wall of the plug body. An outlet terminal is provided at the lower end of the flexible tube, and the outlet terminal passes through the flexible tube and the cavity via a phase wire, a ground wire, and a ground wire, connecting to the inlet terminal on the side wall of the plug body. The detection circuit is connected between the phase wire and the ground wire, and is also connected to a power filter via a circuit. The switch K is connected to the ground wire, and the circuit connects the detection circuit to the power filter. By setting up the switch K and the detection circuit, the grounding status of the socket is detected, and then the switch K is disconnected, which can improve the safety of the washing machine. However, due to its structural limitations, it cannot protect against electric shock to users when the washing machine lid is opened. Therefore, it is easy to cause problems such as poor household grounding and water in the drum, resulting in low user safety when the lid is accidentally opened. In addition, when the switch K is damaged, it can easily reduce the stability of the entire circuit. Utility Model Content

[0005] In view of this, the present invention aims to propose a filter grounding protection system and a variable frequency washing machine to solve the problems existing in the technology, such as the low safety of the filter grounding device in the existing variable frequency washing machine under poor household grounding conditions, which can easily lead to a large leakage voltage in the washing machine and cause users to feel an electric shock, and the limited protection range of the existing grounding detection plug. This aims to optimize the system structure, improve the system stability and reliability, reduce the system cost, enhance the system's protection level during user operation, thereby improving user safety and reliability and increasing user satisfaction.

[0006] To achieve the above objectives, the technical solution of this utility model is implemented as follows:

[0007] This utility model relates to a filter grounding protection system and a variable frequency washing machine. The filter grounding protection system includes a first protection module, a second protection module, and a heating element. One end of the first protection module is connected to the live wire AC-L, and the other end of the first protection module is connected to the current input terminal of the heating element. The heating element is disposed between the inner and outer tubs of the variable frequency washing machine. The outer shell of the heating element is grounded. One end of the second protection module is grounded, and the other end of the second protection module is disposed inside the filter.

[0008] Furthermore, the first protection module includes a main relay and a door relay. Pin 3 of the main relay is connected to the live wire AC-L, pin 4 of the main relay is connected to pin 3 of the door relay via a heating element, pin 1 of the door relay is connected to pin 12 of the main control chip U60, pin 1 of the main relay is electrically connected to pin 11 of the main control chip U60, pin 2 of both the main relay and the door relay are electrically connected to the DC power supply VCC, and pin 4 of the door relay is connected to the neutral wire AC-N.

[0009] Furthermore, the main control chip U60 is located on the computer board of the inverter washing machine.

[0010] Furthermore, the first protection module also includes a thyristor, one end of which is electrically connected to pin 4 of the main relay, and the other end of which is electrically connected to the current input terminal of the heating tube.

[0011] Furthermore, the second protection module includes a ground protection relay J1, a filter output circuit, and a switch control circuit. One end of the filter output circuit is connected to the live wire input terminal L and the neutral wire input terminal N of the power grid, respectively. The other end of the filter output circuit is connected to the switch control circuit and the ground wire E of the power grid through the ground protection relay J1.

[0012] Furthermore, the filter output circuit includes a first Y capacitor CY1, a second Y capacitor CY2, a common-mode inductor L1, and a fuse F. One end of the first Y capacitor CY1 is connected to the neutral line AC-N and pin 2 of the common-mode inductor L1, respectively. The other end of the first Y capacitor CY1 is connected to the switch of the ground protection relay J1 and one end of the second Y capacitor CY2, respectively. The other end of the second Y capacitor CY2 is connected to the live line AC-L and pin 3 of the common-mode inductor L1, respectively. Pin 4 of the common-mode inductor L1 is connected to the live line input L of the power grid through the fuse F, and pin 1 of the common-mode inductor L1 is connected to the neutral line input N of the power grid.

[0013] Furthermore, the filter output circuit also includes a third resistor Rx1, a fourth resistor Rx2, a fifth resistor Rx3, an X capacitor CX2, and a varistor RV1. One end of the third resistor Rx1 is electrically connected to pin 1 of the common-mode inductor L1, one end of the X capacitor CX2, one end of the varistor RV1, and the neutral input N of the power grid, respectively. The other end of the third resistor Rx1 is electrically connected to pin 4 of the common-mode inductor L1, the other end of the X capacitor CX2, the varistor RV1, and the fuse F, respectively, through the fourth resistor Rx2 and the fifth resistor Rx3.

[0014] Furthermore, the switch control circuit includes a diode D1, a first resistor R1, a second resistor R2, and a transistor V1. One end of diode D1 is connected in parallel with one end of the coil of the ground protection relay J1 and then connected to the DC power supply VCC. The other end of diode D1 is connected in parallel with the other end of the coil of the ground protection relay J1 and then connected to the collector of transistor V1. The base of transistor V1 is connected to one end of the first resistor R1 and one end of the second resistor R2. The other end of the second resistor R2 is connected in parallel with the emitter of transistor V1 and grounded. The other end of the first resistor R1 is connected to pin 6 of the main control chip U60.

[0015] Furthermore, the voltage value of the DC power supply VCC is +12V.

[0016] A variable frequency washing machine includes a protection system for grounding a filter, the system being installed inside the variable frequency washing machine.

[0017] Compared with the prior art, the filter grounding protection system and variable frequency washing machine described in this utility model have the following advantages:

[0018] By configuring the system, the system structure can be optimized, the system stability and reliability can be improved, and the system cost can be reduced; the system's protection during user operation can be enhanced, thereby improving user security and reliability and increasing user satisfaction. Attached Figure Description

[0019] The accompanying drawings, which constitute a part of this utility model, are used to provide a further understanding of the utility model. The illustrative embodiments and descriptions of the utility model are used to explain the utility model and do not constitute an undue limitation of the utility model. In the drawings:

[0020] Figure 1 This is a schematic diagram of the overall structure of a protection system for grounding a filter.

[0021] Figure 2 This is a schematic diagram of the main control chip U60 that regulates the main relay switch in the system.

[0022] Explanation of reference numerals in the attached diagram: 10, First protection module; 11, Main relay; 12, Thyristor; 13, Gate relay; 20, Second protection module; 30, Heating element. Detailed Implementation

[0023] The inventive concepts of this disclosure will be described below using terminology commonly used by those skilled in the art to convey the essence of their work to others skilled in the art. However, these inventive concepts may be embodied in many different forms and should not be construed as limited to the embodiments described herein.

[0024] It should be noted that, unless otherwise specified, the embodiments and features described in these embodiments can be combined with each other.

[0025] The present invention will now be described in detail with reference to the accompanying drawings and embodiments.

[0026] This embodiment is for a variable frequency washing machine. Similar to a conventional variable frequency washing machine, the overall structure consists of a variable frequency motor, an inner tub, an outer tub, and a transmission mechanism.

[0027] In existing technology, the grounding device of the filter in the existing inverter washing machine usually has the grounding wire directly connected to the capacitor, which will divide the 110V voltage and connect it to the inner drum through the heater. When the user's home grounding is poor, the user may feel a tingling sensation.

[0028] To address the issues of low safety and potential for high voltage leakage in existing inverter washing machines under poor household grounding conditions, which can cause electric shocks, as well as the large space requirements and high cost of existing devices, this embodiment proposes a filter grounding protection system and an inverter washing machine. The filter grounding protection system includes a first protection module 10, a second protection module 20, and a heating element 30. One end of the first protection module 10 is connected to the live wire AC-L, and the other end is connected to the current input terminal of the heating element 30. The heating element 30 is positioned between the inner and outer tubs of the inverter washing machine. The outer casing of the heating element 30 is grounded and immersed in water within the washing machine tub. One end of the second protection module 20 is grounded, and the other end is located within the filter. In this embodiment, the current input terminal of the heating element 30 is as follows: Figure 1 The AC-L' terminal is shown.

[0029] By configuring the system, the system structure can be optimized, the system stability and reliability can be improved, and the system cost can be reduced; the system's protection during user operation can be enhanced, thereby improving user security and reliability and increasing user satisfaction.

[0030] The first protection module 10 includes a main relay 11 and a door relay 13. Pin 3 of the main relay 11 is connected to the live wire AC-L, and pin 4 of the main relay 11 is connected to pin 3 of the door relay 13 via the heating element 30. Pin 1 of the door relay 13 is connected to pin 12 of the main control chip U60, used to control the door relay 13 to switch on and off accordingly after the computer board detects the open / closed state of the washing machine door. Pin 1 of the main relay 11 is electrically connected to pin 11 of the main control chip U60, and pins 2 of both the main relay 11 and the door relay 13 are electrically connected to the DC power supply VCC; pin 4 of the door relay 13 is connected to the neutral wire AC-N. The main control chip U60 is located on the CPU of the inverter washing machine's computer board and is used to adjust the switching of the main relay 11 and the door relay 13 under the control of the CPU.

[0031] Unlike existing technologies that only disconnect one side of the heating element 30 via the door relay 13 (which doesn't completely disconnect the heating element 30 and still poses a risk of electric shock to users), this application, through the coordinated arrangement of the main relay 11 and the door relay 13, effectively achieves real-time monitoring and feedback of the door opening and closing status. When the door opens, the door relay 13 immediately disconnects one end of the heating element 30, and the main relay 11 disconnects the connection between the heating element 30 and the live wire AC-L, thus achieving first-level leakage protection. This prevents the "induced" voltage from causing electric shock discomfort to some users when the user's household grounding wire E is disconnected when there is water in the tub. Furthermore, the main relay 11 contacts disconnect when the lid is opened, effectively improving user comfort and safety, and enhancing the system stability and reliability of the washing machine.

[0032] In addition, the first protection module 10 also includes a silicon controlled rectifier (SCR) 12, one end of which is electrically connected to pin 4 of the main relay 11, and the other end of which is electrically connected to the current input terminal of the heating tube 30.

[0033] By incorporating the silicon controlled rectifier (SCR) 12, the accuracy of the power output of the heating element 30 can be effectively improved. The SCR can dynamically adjust the conduction angle to control the heating duration or power level, avoiding temperature fluctuations caused by the traditional main relay 11 only being fully on / off. This improves the washing effect and energy efficiency of the washing machine. Furthermore, it extends the lifespan of the main relay 11, reduces electromagnetic interference and surge current. The coordinated design of the SCR 12 and main relay 11 effectively enhances the reliability of the first protection module 10, increases the accuracy of its control over the heating element 30, improves system stability, and reduces system maintenance costs.

[0034] The second protection module 20 includes a ground protection relay J1, a filter output circuit, and a switch control circuit. One end of the filter output circuit is connected to the live wire input terminal L and the neutral wire input terminal N of the power grid through a power plug. The other end of the filter output circuit is connected to the switch control circuit and the ground wire E of the power grid through the ground protection relay J1.

[0035] Unlike existing technologies that typically connect the ground wire directly to the filter output circuit, where the Y capacitor node voltage is 110V, potentially causing a slight tingling sensation in sensitive users without proper grounding, this invention addresses this issue. The ground protection relay J1 effectively improves the safety of the washing machine in situations with poor household grounding, preventing leakage. Furthermore, unlike the existing patent (CN106887775A) which relies solely on switch K, resulting in insufficient protection of the filter's grounding circuit, this application uses a ground protection relay J1 in conjunction with the switch control circuit. This effectively enhances the stability of the connection between the Y capacitor in the filter and the mains ground wire E, providing double leakage protection for the heating element 30, improving system safety and stability, and ensuring user safety.

[0036] The filter output circuit includes a first Y capacitor CY1, a second Y capacitor CY2, a common-mode inductor L1, and a fuse F. One end of the first Y capacitor CY1 is connected to the neutral line AC-N and pin 2 of the common-mode inductor L1, respectively. The other end of the first Y capacitor CY1 is connected to the switch of the ground protection relay J1 and one end of the second Y capacitor CY2, respectively. The other end of the second Y capacitor CY2 is connected to the live line AC-L and pin 3 of the common-mode inductor L1, respectively. Pin 4 of the common-mode inductor L1 is connected to the live line input L of the power grid through the fuse F, and pin 1 of the common-mode inductor L1 is connected to the neutral line input N of the power grid.

[0037] The filter output circuit also includes a third resistor Rx1, a fourth resistor Rx2, a fifth resistor Rx3, an X capacitor CX2, and a varistor RV1. One end of the third resistor Rx1 is electrically connected to pin 1 of the common-mode inductor L1, one end of the X capacitor CX2, one end of the varistor RV1, and the neutral input N of the power grid. The other end of the third resistor Rx1 is electrically connected to pin 4 of the common-mode inductor L1, the other end of the X capacitor CX2, the other end of the varistor RV1, and the fuse F, respectively, through the fourth resistor Rx2 and the fifth resistor Rx3.

[0038] By optimizing the components within the filter circuit, the stability and safety of the circuit can be enhanced. This effectively solves the problems of high-frequency noise and high-voltage surges, and improves the reliability and operational stability of the equipment.

[0039] The switch control circuit includes diode D1, first resistor R1, second resistor R2, and transistor V1. One end of diode D1 is connected in parallel with one end of the coil of ground protection relay J1 and then connected to the DC power supply VCC. The other end of diode D1 is connected in parallel with the other end of the coil of ground protection relay J1 and then connected to the collector of transistor V1. The base of transistor V1 is connected to one end of the first resistor R1 and one end of the second resistor R2. The other end of the second resistor R2 is connected to ground in parallel with the emitter of transistor V1. The other end of the first resistor R1 is connected to pin 6 of the main control chip U60. In this embodiment, the switch control circuit is the control circuit for ground protection relay J1. The DC power supply VCC is a positive power supply with a voltage value of +12V; the specific voltage value of the DC power supply is set as needed. Both the first resistor R1 and the second resistor R2 are fixed resistors. Preferably, the resistance of R1 is 4.7KΩ; the resistance of R2 is 10KΩ; and the model of the ground protection relay J1 is CHM-S-112DA3. The specific resistance values ​​or models of each component are selected according to the requirements.

[0040] By configuring the switch control circuit, efficient control of the ground protection relay J1 can be achieved, ensuring the safety of the ground protection relay J1 during washing machine operation and extending its service life. Furthermore, the use of two fixed resistors, R1 and R2, helps protect the circuit. The second resistor R2 also stabilizes the static operating point, preventing false triggering caused by leakage current in transistor V1. This improves the safety and stability of the device, enhancing user safety and satisfaction.

[0041] A variable frequency washing machine includes a filter grounding protection system, which is installed inside the washing machine. Specifically, the first protection module 10 and the second protection module 20 are both installed on the computer board inside the washing machine. The grounding protection relay J1 is electrically connected to the Y capacitors CY1 and CY2 in the filter output circuit via flexible wires.

[0042] By installing this device inside the inverter washing machine, a ground protection relay J1 can be added to the filter grounding wire E of the inverter washing machine. When the door is detected to be open, the filter grounding wire E is disconnected, so that the voltage drop of the filter cannot enter the heater. At the same time, the main relay 11 and the door relay 13 near the heating tube 30 are disconnected, so that the heating tube 30 is completely de-energized and cannot generate induced voltage. This ensures that the voltage and current of the inner tub to ground are less than the human body's perception value under various conditions of user grounding failure, so that the user does not feel anything and the user's safety and experience are guaranteed.

[0043] In this utility model, any variable frequency washing machine can include a filter grounding protection system structure as described in this embodiment. In addition to the relevant structures and assembly relationships of the flexible wire, relay, and transistor V1 provided in this embodiment, the variable frequency washing machine also includes conventional components such as a variable frequency motor, inner tub, outer tub, and transmission mechanism. Since these are all prior art, they will not be described in detail here.

[0044] The above description is only a preferred embodiment of the present utility model and is not intended to limit the present utility model. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present utility model should be included within the protection scope of the present utility model.

Claims

1. A protection system for filter grounding, characterized in that, It includes a first protection module (10), a second protection module (20), and a heating tube (30). One end of the first protection module (10) is connected to the live wire AC-L, and the other end of the first protection module (10) is connected to the current input terminal of the heating tube (30). The heating tube (30) is set between the inner tub and the outer tub of the variable frequency washing machine. The outer shell of the heating tube (30) is grounded. One end of the second protection module (20) is grounded, and the other end of the second protection module (20) is set inside the filter. The first protection module (10) includes a main relay (11) and a door relay (13); pin 3 of the main relay (11) is connected to the live wire AC-L, pin 4 of the main relay (11) is connected to pin 3 of the door relay (13) through the heating tube (30), pin 1 of the door relay (13) is connected to pin 12 of the main control chip U60, pin 1 of the main relay (11) is electrically connected to pin 11 of the main control chip U60, pin 2 of both the main relay (11) and the door relay (13) are electrically connected to the DC power supply VCC, and pin 4 of the door relay (13) is connected to the neutral wire AC-N. The second protection module (20) includes a ground protection relay J1, a filter output circuit and a switch control circuit. One end of the filter output circuit is connected to the live wire input terminal L and the neutral wire input terminal N of the power grid, respectively. The other end of the filter output circuit is connected to the switch control circuit and the ground wire E of the power grid through the ground protection relay J1.

2. The filter grounding protection system according to claim 1, characterized in that, The main control chip U60 is located on the computer board of the inverter washing machine.

3. The filter grounding protection system according to claim 1, characterized in that, The first protection module (10) also includes a thyristor (12), one end of which is electrically connected to pin 4 of the main relay (11), and the other end of which is electrically connected to the current input terminal of the heating tube (30).

4. The filter grounding protection system according to claim 1, characterized in that, The filter output circuit includes a first Y capacitor CY1, a second Y capacitor CY2, a common-mode inductor L1, and a fuse F. One end of the first Y capacitor CY1 is connected to the neutral line AC-N and pin 2 of the common-mode inductor L1, respectively. The other end of the first Y capacitor CY1 is connected to the switch of the ground protection relay J1 and one end of the second Y capacitor CY2, respectively. The other end of the second Y capacitor CY2 is connected to the live line AC-L and pin 3 of the common-mode inductor L1, respectively. Pin 4 of the common-mode inductor L1 is connected to the live line input L of the power grid through the fuse F, and pin 1 of the common-mode inductor L1 is connected to the neutral line input N of the power grid.

5. The filter grounding protection system according to claim 4, characterized in that, The filter output circuit also includes a third resistor Rx1, a fourth resistor Rx2, a fifth resistor Rx3, an X capacitor CX2, and a varistor RV1; one end of the third resistor Rx1 is electrically connected to pin 1 of the common-mode inductor L1, one end of the X capacitor CX2, one end of the varistor RV1, and the neutral input N of the power grid; the other end of the third resistor Rx1 is electrically connected to pin 4 of the common-mode inductor L1, the other end of the X capacitor CX2, the varistor RV1, and the fuse F in sequence through the fourth resistor Rx2 and the fifth resistor Rx3.

6. The filter grounding protection system according to claim 5, characterized in that, The switch control circuit includes a diode D1, a first resistor R1, a second resistor R2, and a transistor V1. One end of the diode D1 is connected in parallel with one end of the coil of the ground protection relay J1 and then connected to the DC power supply VCC. The other end of the diode D1 is connected in parallel with the other end of the coil of the ground protection relay J1 and then connected to the collector of the transistor V1. The base of the transistor V1 is connected to one end of the first resistor R1 and the second resistor R2 respectively. The other end of the second resistor R2 is connected in parallel with the emitter of the transistor V1 and grounded. The other end of the first resistor R1 is connected to pin 6 of the main control chip U60.

7. A filter grounding protection system according to claim 1, characterized in that, The voltage value of the DC power supply VCC is +12V.

8. A variable frequency washing machine, characterized in that, The washing machine includes a filter grounding protection system according to any one of claims 1-7, the system being installed inside the inverter washing machine.

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