Power-on circuit for washing machine and power-on method thereof

[0015] A power-on circuit for a washing machine includes a door cover 1 hinged to a washing machine body, and a control panel that can be operated by a user, the control panel is provided with touch buttons, and the washing machine body is in contact with the door cover 1 A linkage switch is arranged at the position of the door lock or in the keyhole of the door lock. The linkage switch is connected in parallel with the main control relay 2 and is connected with the main control chip MCU 4 through the transformer 3 . For the pulsator washing machine, the linkage switch includes a safety switch assembly 6 disposed below the door cover 1 and in contact with the lower end surface of the door cover 1, and a safety switch assembly 6 disposed below the safety switch assembly 6 and in the stroke of the safety switch assembly 6 The micro switch 5 inside, the safety switch assembly 6 is linked with the micro switch 5, the micro switch 5 is connected in parallel with the main control relay 2, the micro switch 5 is connected with the main control chip MCU 4 through the transformer 3, and the micro switch 5 is normally open switch, or normally closed switch, such as figure 1 , 2 , 3 shown.

[0016] When in use, open the door cover 1, the door cover 1 presses the safety switch assembly 6, the safety switch assembly 6 moves downward, presses the micro switch 5 to close the micro switch 5, the control panel is powered on, the main control chip MCU 4 to close the main control relay 2, such as figure 2 During the washing process, close the door cover 1, close the micro switch 5, and the control panel is still electrified. That is to say, power-on means that one end of the micro switch 5 is connected to the live wire, and the other end is connected to the power input terminal of the control panel. The user needs to open the washing machine door cover 1 when using the washing machine. At this time, the micro switch 5 is blocked by the safety switch component. 6 Press to close, the control panel is powered on, the program runs normally, and then controls the main control relay 2 to close; when the door cover 1 is closed, the micro switch 5 is turned off, and the power is maintained by the closed main control relay 2. Supply, like image 3 shown.

[0017] When the user opens the door cover 1 and then closes the door cover 1, the control panel is powered on, and the main control chip MCU 4 detects whether there is a signal input on the control panel within a set time. If the detection result is no, the main control chip The MCU 4 drives the main control relay 2 to disconnect, and the control panel is powered off.

[0018] When the user opens the door cover 1 but does not close the door cover 1 and the washing machine is rinsing, the main control chip MCU 4 drives the safety switch assembly 6 to issue an alarm signal prompting the user to close the door cover 1 and stops the rinsing operation.

[0019] When the user does not close the door cover 1 after opening the door cover 1, and the washing machine is not working, the main control chip MCU 4 detects whether there is a signal input on the control panel within a set time, and if the detection result is no, it drives the The main control relay 2 is disconnected and the control panel is powered off. At this time, the micro switch 5 is still closed. When the door cover 1 is closed again, the micro switch 5 is disconnected and the control panel is powered off.

[0020] combine Figure 4 , 5 , For the front-loading washing machine, the door lock is a PTC door lock. The characteristics of the front-loading washing machine PTC door lock are as follows: First, the PTC door lock generally has three wires, the first and second wires are connected to the thermistor PTC, The third wire is for conducting power and feedback. Second, the control panel is locked after the door cover 1 is closed, and the program controls the action of the thermistor PTC. After the thermal expansion of the thermistor PTC, the internal metal linkage mechanism has two results: one is that the pin is inserted and the door hook is locked. ; Second, the internal contact of the third wire is energized after being connected to connect the heating pipe, motor, water inlet valve, etc. Third, the door cover 1 is not closed and the control panel is locked, and the program controls the action of the thermistor PTC. After the thermal expansion of the thermistor PTC, the internal metal linkage mechanism has two results: one is that the pin cannot be inserted because the door hook is not inserted. Insertion produces a lock; second, the internal contact of the third wire is not turned on. Because the detection circuit is integrated inside the computer board, it detects that the action is not completed, so the program will not continue to execute. Fourth, because the thermal expansion and cooling of the thermistor PTC takes time, it needs to wait for a period of time to recover after the pause and the program is over before the lock can be released. The thermistor PTC is always in the power-on state during the operation.

[0021] Utilizing the above-mentioned features of the PTC door lock, the linkage switch is a micro switch 5 arranged in the PTC door lock keyhole of the washing machine, and the micro switch 5 is located above the PTC door lock slide 7 and is located in the PTC door lock slide 7 The PTC door lock slide 7 is linked with the micro switch 5 within the stroke of the PTC door lock. The PTC door lock slide 7 is located on the PTC door lock frame 8. It is connected with the main control chip MCU 4.

[0022] When the door cover 1 is closed, the door hook snaps into the lock hole of the door lock to drive the PTC door lock slide 7 to move and make the micro switch 5 just in free travel, such as Figure 4 When the door cover 1 is opened, the door hook pops out from the door lock hole, and the PTC door lock slide 7 slides so that the micro switch 5 inside is just pressed and closed, as shown in the figure. Figure 5 As shown, the power-on function is the same as above. A micro switch 5 can also be provided at the position where the drum washing machine body is in contact with the door cover 1, and the action part of the micro switch 5 is extended or extended through a mechanism that relies on a spring to return, and the door cover is used. The pressure after closing 1 achieves the purpose of touching and releasing the micro switch 5. The micro switch 5 can also be designed as normally open and normally closed types, both of which can be normally energized when the door cover 1 is opened.