Laundry machine door detection circuit and laundry machine

Abstract

The application provides a washing machine door detection circuit and a washing machine. The circuit comprises a door switch module, a control module and a detection module. The door switch module is connected with a first power supply and the control module, and is configured to output a signal of the first power supply to the control module when the door switch module is closed. The control module comprises a plurality of parallel control branches. Each control branch comprises a first control switch. A first end of the first control switch is connected with a second power supply. First control switches of adjacent control branches are connected in a head-to-tail manner. A second end of the first control switch in the last control branch is connected with the detection module. The first control branch is configured to control the corresponding first control switch to be turned on in response to the signal of the first power supply. The detection module is configured to output a first signal in response to the signal of the second power supply. The first signal represents that the door of the washing machine is closed. Through the design of the plurality of parallel control branches, the single-point failure problem of the circuit can be effectively prevented.

Description

TECHNICAL FIELD

[0001] The application belongs to the technical field of electronics, and particularly relates to a washing machine door detection circuit and a washing machine. BACKGROUND

[0002] The strong electric door lock or door switch of a washing machine is an important component related to the safety of the washing machine, which is manually or automatically turned on when the door of the washing machine is closed. The strong electric door lock generally refers to a safety device that needs to be connected to alternating current mains, and the door switch generally refers to a safety device that is connected to direct current weak electricity. The state detection of the door of the washing machine is a key step to ensure the safety of the washing machine. When the door of the washing machine is detected to be safely closed, that is, the strong electric door lock or the door switch is turned on, the motor of the washing machine can normally work.

[0003] However, in the existing washing machine door state detection scheme, if some components in the circuit fail to cause a short circuit, a false detection problem may be caused, that is, a washing machine door that is not closed is identified as being normally closed, which causes a false action problem of the washing machine and constitutes a safety hazard.

[0004] Therefore, a washing machine door state detection circuit capable of preventing single-point failure of the circuit is needed. SUMMARY

[0005] The application provides a washing machine door detection circuit and a washing machine to solve the problem of single-point failure of the circuit in the washing machine door state detection process.

[0006] In a first aspect, the application provides a washing machine door detection circuit, comprising: a door switch module, a control module, and a detection module; wherein,

[0007] The door switch module is connected with a first power supply and the control module, and is configured to output a signal of the first power supply to the control module when the door switch module is closed;

[0008] The control module comprises a plurality of parallel control branches, wherein the control branch comprises a first control switch, a first end of the first control switch is connected with a second power supply, a second end of the first control switch in the control branch is connected with a first end of a first control switch in an adjacent control branch, and a second end of the first control switch in the last control branch is connected with the detection module. The first control branch is configured to control the first control switch to be turned on in response to the signal of the first power supply.

[0009] The detection module is configured to output a first signal in response to a signal of the second power supply, and the first signal represents that the door of the washing machine is closed.

[0010] Optionally, the door switch module comprises a first door switch module, and the first door switch module comprises a door switch, a first impedance, and a second impedance.

[0011] The first end of the door switch is connected with a third power supply, and the second end of the door switch is connected with the first end of the first impedance and the first end of the second impedance; the second end of the first impedance is connected with the control module and the ground, and the second end of the second impedance is grounded.

[0012] Optionally, the door switch module comprises a second door switch module, and the second door switch module comprises a door lock switch, a first optocoupler module and a second optocoupler module.

[0013] The positive emission end of the first optocoupler module is connected with an AC power supply live wire, the negative emission end of the first optocoupler module is connected with the positive emission end of the second optocoupler module, the negative emission end of the second optocoupler module is connected with the first end of the door lock switch, and the second end of the door lock switch is connected with an AC power supply ground wire.

[0014] The positive receiving end of the first optocoupler module is connected with a fourth power supply, the negative receiving end of the first optocoupler module is connected with the positive receiving end of the second optocoupler module, and the negative receiving end of the second optocoupler module is connected with the control module.

[0015] Optionally, the second door switch module further comprises a third impedance, a first diode, a fourth impedance and a second diode.

[0016] The anode of the first diode is connected with the AC power supply live wire, and the cathode is connected with the first end of the third impedance; the second end of the third impedance is connected with the positive emission end of the first optocoupler module.

[0017] The first end of the fourth impedance is connected with the negative receiving end of the second optocoupler module, the second end of the fourth impedance is connected with the anode of the second diode, and the cathode of the second diode is connected with the control module.

[0018] Optionally, the control branch further comprises a second control switch, a third diode, a fifth impedance and a sixth impedance.

[0019] The anode of the third diode is connected with the door switch module, the cathode of the third diode is connected with the first end of the fifth impedance, the second end of the fifth impedance is connected with the first end of the sixth impedance and the control end of the second control switch, and the second end of the sixth impedance is grounded.

[0020] The first end of the second control switch is connected with the control end of the first control switch and the second power supply, and the second end of the second control switch is grounded.

[0021] Optionally, the control branch further comprises a seventh impedance and an eighth impedance.

[0022] The first end of the seventh impedance is connected to the first end of the second control switch, and the second end of the seventh impedance is connected to the control end of the first control switch and the first end of the eighth impedance; and the second end of the eighth impedance is connected to the first end of the first control switch.

[0023] Optionally, the control branch further comprises a ninth impedance, a tenth impedance and an eleventh impedance.

[0024] The first end of the ninth impedance is connected to the first end of the second control switch and the second end of the tenth impedance, and the first end of the tenth impedance is connected to the second power supply.

[0025] The second end of the ninth impedance is connected to the control end of the first control switch and the first end of the eleventh impedance, and the second end of the eleventh impedance is connected to the first end of the first control switch.

[0026] Optionally, the control module further comprises a first capacitor.

[0027] The first end of the first capacitor is connected to the anode of the third diode in each control branch, and the second end of the first capacitor is grounded.

[0028] Optionally, the detection module comprises a plurality of detection branches, and each detection branch comprises a detection switch; wherein the control ends of the detection switches in adjacent detection branches are connected and connected to a relay power supply.

[0029] The control end of the detection switch in the detection branch is connected to the control module, the first end of the detection switch is connected to a corresponding detection signal and a fourth power supply, and the second end of the detection switch is grounded.

[0030] Optionally, the detection branch further comprises a voltage reduction resistor, a first shunt resistor and a second shunt resistor.

[0031] The first end of the voltage reduction resistor is connected to the control module, the second end of the voltage reduction resistor is connected to the first end of the first shunt resistor and the first end of the second shunt resistor; the second end of the first shunt resistor is connected to the control end of the detection switch; and the second end of the second shunt resistor is connected to the second end of the detection switch.

[0032] Optionally, the detection branch further comprises a second pull-up resistor, a fourth current limiting resistor and a second capacitor.

[0033] The first end of the second pull-up resistor is connected to the fourth power supply, and the second end of the second pull-up resistor is connected to the first end of the detection switch; the first end of the fourth current-limiting resistor is connected to the second end of the second pull-up resistor, the second end of the fourth current-limiting resistor is connected to the first end of the second capacitor and the corresponding detection signal of the detection switch, and the second end of the second capacitor is grounded.

[0034] In a second aspect, the application provides a washing machine, comprising: the washing machine door detection circuit, the microprocessor and the overload protection module according to the first aspect; wherein the overload protection module comprises a protection switch and a system main relay.

[0035] The microprocessor is connected to the washing machine door detection circuit; the control end of the system main relay is connected to the first end of the protection switch, the second end of the protection switch is grounded; and the control end of the protection switch is connected to the microprocessor.

[0036] Optionally, the overload protection module further comprises a twelfth impedance and a thirteenth impedance.

[0037] The first end of the twelfth impedance is connected to the microprocessor, the second end of the twelfth impedance is connected to the control end of the protection switch and the first end of the thirteenth impedance, and the second end of the thirteenth impedance is grounded.

[0038] The application provides a washing machine door detection circuit and a washing machine, the circuit comprising: a door switch module, a control module and a detection module; wherein the door switch module is connected to a first power supply and the control module, and is configured to output a signal of the first power supply to the control module when the door switch module is closed; the control module comprises a plurality of parallel control branches, wherein the control branch comprises a first control switch, the first end of the first control switch is connected to a second power supply, the second end of the first control switch in the control branch is connected to the first end of the first control switch in the adjacent control branch, and the second end of the first control switch in the last control branch is connected to the detection module, the first control branch is configured to control the first control switch to be turned on in response to the signal of the first power supply; and the detection module is configured to output a first signal in response to the signal of the second power supply, the first signal representing that the door of the washing machine is closed. The switching signal is transformed and responded by the control module, and the transmission of the switching signal is completed by the detection module, so that the microprocessor can identify and detect the switching signal, and meanwhile, the design of the plurality of parallel control branches can effectively prevent single-point failure of the circuit. BRIEF DESCRIPTION OF DRAWINGS

[0039] The accompanying drawings, which are incorporated herein and form a part of the specification, illustrate embodiments consistent with the present application and, together with the description, further serve to explain the principles of the application. The embodiments of this application will be described with reference to the drawings in which:

[0040] Figure 1 A schematic diagram of a washing machine door state detection application scenario is shown;

[0041] Figure 2 A schematic diagram of a washing machine door detection circuit structure provided by Embodiment One of the present application is shown;

[0042] Figure 3 A schematic diagram of a washing machine door detection circuit structure provided by Embodiment Two of the present application is shown;

[0043] Figure 4 A schematic diagram of a washing machine door detection circuit structure provided by Embodiment Three of the present application is shown;

[0044] Figure 5 A schematic diagram of another washing machine door detection circuit structure provided by Embodiment Three of the present application is shown;

[0045] Figure 6 A schematic diagram of a washing machine door detection circuit structure provided by Embodiment Four of the present application is shown;

[0046] Figure 7 A schematic diagram of another washing machine door detection circuit structure provided by Embodiment Four of the present application is shown;

[0047] Figure 8 A schematic diagram of another washing machine door detection circuit structure provided by Embodiment Four of the present application is shown;

[0048] Figure 9 A schematic diagram of another washing machine door detection circuit structure provided by Embodiment Four of the present application is shown;

[0049] Figure 10 A schematic diagram of a washing machine door detection circuit structure provided by Embodiment Five of the present application is shown;

[0050] Figure 11 A schematic diagram of another washing machine door detection circuit structure provided by Embodiment Five of the present application is shown;

[0051] Figure 12 A schematic diagram of another washing machine door detection circuit structure provided by Embodiment Five of the present application is shown;

[0052] Figure 13 A schematic diagram of a washing machine structure provided by Embodiment Six of the present application is shown;

[0053] Figure 14 A schematic diagram of another washing machine structure provided by Embodiment Six of the present application is shown;

[0054] Figure 15 Another washing machine structure diagram is provided for the sixth embodiment of the present application.

[0055] The specific embodiments of the present application have been shown through the above-described drawings, and will be described in more detail hereinafter. The drawings and the written description are not intended to limit the scope of the present application in any way, but to explain the concept of the present application to those skilled in the art by referring to specific embodiments. DETAILED DESCRIPTION

[0056] Exemplary embodiments will be described in detail with reference to the drawings, of which examples are shown. Unless otherwise noted, the same numbers in different drawings indicate the same or similar elements. The embodiments described in the following exemplary embodiments are not meant to represent all implementations consistent with the present application. Rather, they are merely examples of apparatus and methods consistent with some aspects of the present application as detailed in the appended claims.

[0057] Figure 1 A washing machine door state detection application scenario diagram is provided to illustrate the washing machine door state mis-detection phenomenon caused by single-point failure of the circuit.

[0058] As shown in Figure 1 1000 is a washing machine with a door state detection function, 101 is the door cover of the washing machine, and the door cover is in an open state at this time. In theory, the load part of the washing machine, such as the motor, should not be powered on at this time. 102 is the door lock or door switch of the washing machine, 103 is the motor of the washing machine, 104 is the microprocessor of the washing machine, and 105 is the status display screen of the washing machine. The door lock or door switch 102, the motor 103, and the status display screen 105 are all connected to the microprocessor 104. When the door cover 101 is opened, the door lock or door switch 102 is not turned on at this time, but due to the short circuit phenomenon caused by the failure of individual components in the processing circuit, the microprocessor 104 receives the wrong 102 closed signal, and sends a signal to make the control circuit power on the motor 103. The status display screen 105 displays that the washing machine is in a state where the door lock is turned on and the motor is ready. At this time, due to the occurrence of single-point failure in the circuit, the microprocessor 104 has misdetected and incorrectly powered on the motor 103 and other loads. If the start switch is accidentally touched and misstarted, it will cause great safety hazards. At the same time, 102 can be a strong door lock or a weak door switch. When 102 adopts different devices, the corresponding detection circuit structure will be quite different, and cannot be compatible. Therefore, it is necessary to design a washing machine door detection circuit that is compatible with various door cover switches and can prevent single-point failure phenomenon.

[0059] The technical solutions of the present application and the technical solutions of the present application will be described in detail below with specific examples. The following specific examples can be combined with each other, and the same or similar concepts or processes may not be described again in some examples. In the description of the present application, unless otherwise explicitly specified and limited, each term should be understood broadly in the art. The embodiments of the present application will be described below with reference to the accompanying drawings.

[0060] Embodiment one

[0061] Figure 2 A structural schematic diagram of a washing machine door detection circuit provided by the present application is shown in Figure 2 The circuit includes a door switch module 11, a control module 12, and a detection module 13; wherein,

[0062] The door switch module 11 is connected with the first power supply and the control module 12, and is used to output the signal of the first power supply to the control module 12 when the door switch module 11 is closed;

[0063] The control module 12 includes a plurality of parallel control branches, wherein the control branch includes a first control switch 101, the first end of the first control switch is connected with the second power supply, the second end of the first control switch in the control branch is connected with the first end of the first control switch in the adjacent control branch, and the second end of the first control switch in the last control branch is connected with the detection module, and the first control branch is used to control the first control switch to be turned on in response to the signal of the first power supply;

[0064] The detection module 13 is used to output a first signal in response to the signal of the second power supply, and the first signal represents that the washing machine door is closed.

[0065] The present embodiment will be described in detail in combination with a specific application scenario: the door switch module 11 is connected with the first power supply, which can be an alternating current mains or a direct current power supply for driving the door switch, so the present application is applicable to strong electric door locks and weak electric switches. The door switch module 11 is used to output the signal of the first power supply to the control module 12 when the door switch module 11 is closed, that is, to make the control module 12 able to receive the information that the door is closed.

[0066] As shown in the figure, the control module 12 includes a plurality of parallel control branches, wherein the control branch includes a first control switch 101. It should be noted that only the key element of the control branch, the first control switch 101, is shown in the figure, and in actual application, a series of other elements should be used in cooperation, otherwise the first control switch 101 may not function normally in some cases. The first control switch 101 is usually a triode, and the example shown in the figure shows a case of selecting a PNP type triode. The first end of the first control switch 101 is connected to the second power supply, the second end is connected to the first end of the first control switch 101 in the adjacent control branch, and the first control switches 101 corresponding to the plurality of parallel control branches are connected end to end in accordance with this rule, and the second end of the first control switch 101 in the last control branch is connected to the detection module. The first control branch is used to control the first control switch 101 to conduct in response to the signal of the first power supply, at this time, the detection module 13 can output a first signal representing that the door of the washing machine is closed in response to the signal of the second power supply, and the detection of the door switch state is completed.

[0067] The embodiment provides a washing machine door detection circuit, which comprises a door switch module, a control module and a detection module; wherein the door switch module is connected with a first power supply and the control module, and is used to output a signal of the first power supply to the control module when the door switch module is closed; the control module comprises a plurality of parallel control branches, wherein the control branch comprises a first control switch, the first end of the first control switch is connected to a second power supply, the second end of the first control switch in the control branch is connected to the first end of the first control switch in the adjacent control branch, and the second end of the first control switch in the last control branch is connected to the detection module, and the first control branch is used to control the first control switch to conduct in response to the signal of the first power supply; the detection module is used to output a first signal in response to the signal of the second power supply, and the first signal represents that the door of the washing machine is closed. The switching signal is transformed and responded through the control module, and the transmission of the switching signal is completed through the detection module, so that the microprocessor can identify and detect the switching signal, and at the same time, the design of the plurality of parallel control branches can effectively prevent the single point failure of the circuit.

[0068] Embodiment two

[0069] Figure 3 A structure schematic diagram of a washing machine door detection circuit provided for the second embodiment of the application is shown in the figure, which is based on any one of the other embodiments, and as shown in the figure, the door switch module 11 specifically comprises: Figure 3

[0070] The first door switch module 21 comprises a door switch 201, a first impedance 202 and a second impedance 203.

[0071] ​The first end of the door switch 201 is connected to the third power supply, and the second end of the door switch 201 is connected to the first end of the first impedance 202 and the first end of the second impedance 203; the second end of the first impedance 202 is connected to the control module 12 and the ground, and the second end of the second impedance 203 is grounded.

[0072] The first door switch module 21 is a weak current switch, and the third power supply is a direct current power supply, that is, a VCC. The third power supply can also be the same as the second power supply, but Figure 3 Only a case where the third power supply and the second power supply are designed separately is shown. In the first door switch module 21, the first impedance 202 and the second impedance 203 are further included, the first end of the door switch 201 is connected to the third power supply, the second end of the door switch 201 is connected to the first end of the first impedance 202 and the first end of the second impedance 203; the second end of the first impedance 202 is connected to the control module 12 and the ground, and the second end of the second impedance 203 is grounded. The first impedance 202 is a current-limiting resistor that limits the current flowing into the control module to prevent damage to the components in the control module, and the second impedance 203 is a pull-down resistor to clamp the potential at the first end of the second impedance to a low potential when the circuit is not connected to an external power supply.

[0073] The embodiment provides a washing machine door detection circuit, and the door switch module includes: a first door switch module, the first door switch module includes: a door switch, a first impedance and a second impedance; the first end of the door switch is connected to a third power supply, and the second end of the door switch is connected to the first end of the first impedance and the first end of the second impedance; the second end of the first impedance is connected to the control module and the ground, and the second end of the second impedance is grounded. Through the design of the weak current door switch module matching circuit, the control module can receive the conduction information of the door switch, and the detection module can make a corresponding response.

[0074] Embodiment three

[0075] Figure 4 A structure diagram of a washing machine door detection circuit provided for the third embodiment of the application is shown in FIG. 11, which is based on any one of the other embodiments, and specifically includes: Figure 4

[0076] The second door switch module 31 includes a door lock switch 301, a first optocoupler module 302 and a second optocoupler module 303.

[0077] ​The positive electrode of the transmitting end of the first optocoupler module 302 is connected with the live wire of the AC mains, the negative electrode of the transmitting end of the first optocoupler module 302 is connected with the positive electrode of the transmitting end of the second optocoupler module 303, the negative electrode of the transmitting end of the second optocoupler module 303 is connected with the first end of the door lock switch 301, and the second end of the door lock switch 301 is connected with the ground wire of the AC mains.

[0078] The positive electrode of the receiving end of the first optocoupler module 302 is connected with the fourth power supply, the negative electrode of the receiving end of the first optocoupler module 302 is connected with the positive electrode of the receiving end of the second optocoupler module 303, and the negative electrode of the receiving end of the second optocoupler module 303 is connected with the control module.

[0079] The second door switch module 31 is a switch module applied to a strong electric door lock, which comprises the door lock switch 301, the first optocoupler module 302 and the second optocoupler module 303. The optocoupler module can be used for signal transmission and isolation between the strong and weak electric circuits.

[0080] The positive electrode of the transmitting end of the first optocoupler module 302 is connected with the live wire of the AC mains, the negative electrode of the transmitting end of the first optocoupler module 302 is connected with the positive electrode of the transmitting end of the second optocoupler module 303, the negative electrode of the transmitting end of the second optocoupler module 303 is connected with the first end of the door lock switch 301, and the second end of the door lock switch 301 is connected with the ground wire of the AC mains.

[0081] The positive electrode of the receiving end of the first optocoupler module 302 is connected with the fourth power supply, the fourth power supply is a direct current power supply, and is used for driving the photosensitive triode to work. The negative electrode of the receiving end of the first optocoupler module 302 is connected with the positive electrode of the receiving end of the second optocoupler module 303, and the negative electrode of the receiving end of the second optocoupler module 303 is connected with the control module. It should be noted that the optocoupler module can also complete the corresponding function if only one optocoupler module is arranged. The embodiment provides an example of two optocoupler modules connected in series, which is used for preventing single-point failure of the optocoupler. In actual application, the number of optocoupler modules connected in series can be selected according to the requirements of power consumption and other parameters.

[0082] An example, Figure 5 A structure schematic diagram of another washing machine door detection circuit provided by the embodiment three of the application is shown in Figure 5 The second door switch module 31 further comprises a third impedance 304, a first diode 305, a fourth impedance 306 and a second diode 307.

[0083] The anode of the first diode 305 is connected with the live wire of the AC mains, and the cathode is connected with the first end of the third impedance 304. The second end of the third impedance 304 is connected with the positive electrode of the transmitting end of the first optocoupler module 302.

[0084] The first end of the fourth impedance 306 is connected to the negative pole of the receiving end of the second optical coupling module 303, and the second end of the fourth impedance 306 is connected to the anode of the second diode 307; the cathode of the second diode 307 is connected to the control module 12.

[0085] The diode is used to limit the current direction of the circuit, and the third impedance 304 and the fourth impedance 306 are current limiting resistors, which prevent the elements after the current limiting resistors from being damaged. Specifically, the third impedance 304 is used to limit the current of the strong current side circuit, and the fourth impedance 306 prevents the current flowing into the control module 12 from being too large. Among them, the third impedance 304 and the first diode 305 can be interchanged in position, as long as they are in series; the fourth impedance 306 and the second diode 307 are the same.

[0086] The embodiment provides a washing machine door detection circuit, and the door switch module comprises: a first door switch module, the first door switch module comprising: a door switch, a first impedance and a second impedance; the first end of the door switch is connected to a third power supply, and the second end of the door switch is connected to the first end of the first impedance and the first end of the second impedance; the second end of the first impedance is connected to the control module and the ground, and the second end of the second impedance is grounded. Through the design of the weak current door switch module matching circuit, the control module can receive the conduction information of the door switch, and the detection module can make a corresponding response.

[0087] Embodiment four

[0088] Figure 6 A structure schematic diagram of a washing machine door detection circuit provided by the fourth embodiment of the application is shown in FIG. 4, which is based on any one of the other embodiments. Figure 6 As shown in FIG. 4, the control branch further comprises:

[0089] a second control switch 401, a third diode 402, a fifth impedance 403 and a sixth impedance 404;

[0090] The anode of the third diode 402 is connected to the door switch module 11, and the cathode of the third diode 402 is connected to the first end of the fifth impedance 403; the second end of the fifth impedance 403 is connected to the first end of the sixth impedance 404 and the control end of the second control switch 401, and the second end of the sixth impedance 404 is grounded;

[0091] The first end of the second control switch 401 is connected to the control end of the first control switch 101 and the second power supply, and the second end of the second control switch 401 is grounded.

[0092] The embodiment is described in detail in combination with a specific application scenario: Figure 6Only the structure of one control branch is shown to illustrate the operating principle, and in actual applications, each control branch can be configured in a similar structure to prevent single-point failure. The third diode 402 is used to limit the unidirectional conduction of current, the fifth impedance 403 is used for current limiting, and the sixth impedance 404 is a pull-down resistor of the control end of the second control switch 401 in the control branch. The second control switch 401 can be an N-enhanced field effect transistor as shown, and in actual applications, the model should be selected as appropriate.

[0093] An example, Figure 7 A structure diagram of another washing machine door detection circuit provided in Embodiment Four of the present application is shown in FIG. 4, which is similar to the structure diagram shown in FIG. 3, and the difference is that the control module 12 further includes: Figure 7

[0094] The first end of the first capacitor 405 is connected to the anode of the third diode 402 in each control branch, and the second end of the first capacitor 405 is grounded. The first capacitor 405 is used to delay the turn-off of the second control switch 401 to prevent damage to the control branch components caused by voltage mutation.

[0095] An example, Figure 8 A structure diagram of another washing machine door detection circuit provided in Embodiment Four of the present application is shown in FIG. 4, which is similar to the structure diagram shown in FIG. 3, and the difference is that the control module 12 further includes: Figure 8

[0096] The seventh impedance 406 and the eighth impedance 407;

[0097] The first end of the seventh impedance 406 is connected to the first end of the second control switch 401, the second end of the seventh impedance 406 is connected to the control end of the first control switch 101 and the first end of the eighth impedance 407, and the second end of the eighth impedance 407 is connected to the first end of the first control switch 101. The seventh impedance 406 is a bias resistor that provides a bias current for the normal operation of the first control switch, and the eighth impedance 407 is a load resistor to achieve the function of voltage amplification. This embodiment is used in the first control branch in the parallel control branch, that is, the first end of the first control switch corresponding to the branch is directly connected to the power supply, rather than being connected to the second end of the other first control switch.

[0098] An example, Figure 9 A structure diagram of another washing machine door detection circuit provided in Embodiment Four of the present application is shown in FIG. 4, which is similar to the structure diagram shown in FIG. 3, and the difference is that the control module 12 further includes: Figure 9

[0099] The ninth impedance 408, the tenth impedance 409, and the eleventh impedance 410;

[0100] ​​​The first end of the ninth impedance 408 is connected to the first end of the second control switch 401 and the second end of the tenth impedance 409, and the first end of the tenth impedance 409 is connected to the second power supply;

[0101] The second end of the ninth impedance 408 is connected to the control end of the first control switch 101 and the first end of the eleventh impedance 410, and the second end of the eleventh impedance 410 is connected to the first end of the first control switch 101.

[0102] Correspondingly, the ninth impedance 408 functions similarly to the seventh impedance 406 in the foregoing embodiments, the eleventh impedance 410 functions similarly to the eighth impedance 407 in the foregoing embodiments, and the tenth impedance 409 functions as a pull-up resistor for the first end of the second control switch 401. This embodiment shows a feasible solution for a control branch other than the first control branch in a plurality of parallel control branches, which is embodied as the structure of the last control branch in the figure. In fact, if the number of parallel control branches exceeds two, the structure can be applied to other control branches except for the uppermost control branch as described in the last embodiment.

[0103] The control branch further includes a second control switch, a third diode, a fifth impedance, and a sixth impedance. The anode of the third diode is connected to the door switch module, and the cathode of the third diode is connected to the first end of the fifth impedance. The second end of the fifth impedance is connected to the first end of the sixth impedance and the control end of the second control switch, and the second end of the sixth impedance is grounded. The first end of the second control switch is connected to the control end of the first control switch and the second power supply, and the second end of the second control switch is grounded. Through the design of a plurality of parallel control branches with two control switches, the single-point failure prevention function of the washing machine door detection circuit can be realized.

[0104] Embodiment Five

[0105] Figure 10 A structure schematic diagram of a washing machine door detection circuit provided by Embodiment Five of the present application is shown in FIG. 13, which is based on any one of the other embodiments. As shown in FIG. 13, the detection module 13 includes a plurality of detection branches, and each detection branch includes a detection switch 501. The control ends of the detection switches 501 in adjacent detection branches are connected and connected to a relay power supply. Figure 10

[0106] The control end of the detection switch 501 in the detection branch is connected to the control module 12, the first end of the detection switch 501 is connected to the corresponding detection signal and the fourth power supply, and the second end of the detection switch 501 is grounded.

[0107] ​The embodiment is described in detail in combination with a specific application scene: the detection module 13 includes a plurality of detection branches, the detection branch includes a detection switch 501, and a double detection branch embodiment is shown in the figure, two detection switches are connected to two detection signals respectively, which are actually different pins of the microprocessor, and the fourth power supply simultaneously supplies power to the microprocessor. The relay power supply is a network symbol for indicating the information output by the control module. The detection switch 501 selects an NPN triode in this embodiment, and the selection should be made according to the specific situation in actual application.

[0108] An example, Figure 11 Another structure diagram of a washing machine door detection circuit provided by the fifth embodiment of the application is shown in FIG. 5, which is similar to the structure diagram shown in FIG. 4, and the difference is that the detection branch further includes a second pull-up resistor 505, a fourth current limiting resistor 506 and a second capacitor 507. Figure 11

[0109] The first end of the voltage reduction resistor 502 is connected with the control module 12, the second end of the voltage reduction resistor 502 is connected with the first end of the first shunt resistor 503 and the first end of the second shunt resistor 504, the second end of the first shunt resistor 503 is connected with the control end of the detection switch 501, and the second end of the second shunt resistor 504 is connected with the second end of the detection switch 501. The voltage reduction resistor 502, the first shunt resistor 503 and the second shunt resistor 504 ensure that the signal output by the control module will not damage the components in the detection module, and the detection switch 501 can work normally. Only the structure of one detection branch is shown in the figure, and all the detection branches can select this structure in application.

[0110] An example, Figure 12 Another structure diagram of a washing machine door detection circuit provided by the fifth embodiment of the application is shown in FIG. 5, which is similar to the structure diagram shown in FIG. 4, and the difference is that the detection branch further includes a second pull-up resistor 505, a fourth current limiting resistor 506 and a second capacitor 507. Figure 12

[0111] The first end of the second pull-up resistor 505 is connected with the fourth power supply, the second end of the second pull-up resistor 505 is connected with the first end of the detection switch 501, for limiting the high potential of the first end of the detection switch 501, the first end of the fourth current limiting resistor 506 is connected with the second end of the second pull-up resistor 505, the second end of the fourth current limiting resistor 506 is connected with the first end of the second capacitor 507 and the detection signal corresponding to the detection switch 501, the second end of the second capacitor 507 is grounded, and the fourth current limiting resistor 506 is used for limiting the electrical signal input into the microprocessor and constitutes a filter circuit with the second capacitor 507. Only the structure of one detection branch is shown in the figure, and all the detection branches can select this structure in application.

[0112] ​​The embodiment provides a washing machine door detection circuit, and the detection module comprises: a plurality of detection branches, the detection branch comprises a detection switch; wherein the control ends of the detection switches in adjacent detection branches are connected and connected to a relay power supply; the control end of the detection switch in the detection branch is connected with the control module, the first end of the detection switch is connected with a corresponding detection signal and a fourth power supply, and the second end of the detection switch is grounded. Through the design of the plurality of detection branches, the single-point failure prevention function on the detection branch is realized.

[0113] Embodiment six

[0114] Figure 13 A washing machine structure schematic diagram provided by the embodiment six of the application is shown in the figure, and on the basis of any one of the other embodiments, the washing machine comprises the washing machine door detection circuit, the microprocessor 61 and the overload protection module 62 as described above; wherein the overload protection module comprises a protection switch 601 and a system main relay 602. Figure 13

[0115] The microprocessor 61 is connected with the washing machine door detection circuit; the control end of the system main relay 602 is connected with the first end of the protection switch 601, the second end of the protection switch 601 is grounded, and the control end of the protection switch 601 is connected with the microprocessor 61. The protection switch can be a triode, and the system main relay is used for executing an action, controlling the load such as a motor in the washing machine, and after the microprocessor receives the normally closed switch signal transmitted by the detection module, the main relay can be controlled to perform an action.

[0116] An example, Figure 14 Another washing machine structure schematic diagram provided by the embodiment six of the application is shown in the figure, Figure 14 The overload protection module 62 further comprises a twelfth impedance 603 and a thirteenth impedance 604.

[0117] The first end of the twelfth impedance 603 is connected with the microprocessor 61, the control end of the protection switch 601 and the first end of the thirteenth impedance 604 are connected with the second end of the twelfth impedance 603, and the second end of the thirteenth impedance 604 is grounded. Similar to the description in the previous embodiment, the twelfth impedance 603 is used for current limiting, and the thirteenth impedance 604 is used for pull-down.

[0118] An example, Figure 15 Another washing machine structure schematic diagram provided by the embodiment six of the application is shown in the figure, Figure 15 The washing machine is an example combined with each embodiment.

[0119] (1) When the system is connected with the strong electric door lock

[0120] ​SW2 is a strong electric door lock internal switch, when the door lock is attracted, SW2 is closed. The live wire L passes through diode D2, resistor R11, optocoupler O1, O2, SW2 to return to the neutral wire N. After the optocoupler is turned on, VCC charges capacitor C3 through the optocoupler, resistor R17, and diode D3. At this time, MOS1 and MOS2 are turned on, Q2 and Q3 are turned on. At this time, VCC_relay has power, providing power for the system main relay, and Q1 and Q4 are turned on. The main chip detects the door lock signal and performs corresponding actions.

[0121] When the door lock is opened, SW2 is opened, and after C3 capacitor is discharged, MOS1 and MOS2 are cut off, Q2 and Q3 are cut off. VCC_relay is powered off, the system main relay is powered off, all loads are cut off, and the purpose of opening the load when the door is opened is achieved.

[0122] (2) When the system is connected to a weak electric door switch

[0123] SW1 is a door switch, when the door switch is closed, SW1 is closed. VCC passes through SW1 through resistor R8, D1, D4, at this time, MOS1 and MOS2 are turned on, Q2 and Q3 are turned on. At this time, VCC_relay has power, providing power for the system main relay, and Q1 and Q4 are turned on. The main chip detects the door lock signal and performs corresponding actions.

[0124] When the door switch SW1 is opened, C3 capacitor is discharged, MOS1 and MOS2 are cut off, Q2 and Q3 are cut off. VCC_relay is powered off, the system main relay is powered off, all loads are cut off, and the purpose of opening the load when the door is opened is achieved.

[0125] In this embodiment, MOS tube and triode are designed in double circuit to prevent single point failure when the door lock or door switch is opened. For example, the short circuit of points H and I is shown, although VCC reaches point I, the door lock is opened, and Q3 cannot be turned on, thereby avoiding the potential false detection problem of the circuit when Q2 fails.

[0126] The embodiment provides a washing machine, which comprises a washing machine door detection circuit, a microprocessor and an overload protection module according to any one of the embodiments; wherein the overload protection module comprises a protection switch and a system main relay; the microprocessor is connected with the washing machine door detection circuit; the control end of the system main relay is connected with the first end of the protection switch, and the second end of the protection switch is grounded; and the control end of the protection switch is connected with the microprocessor. The system main relay is connected with a load, and the on-off of the system main relay is controlled through the protection switch, so that the single point failure prevention function of the washing machine door detection circuit can be realized in an actual application scenario.

[0127] So far, the technical solution of the present application has been described in combination with the embodiments shown in the drawings, but it is easy for those skilled in the art to understand that the protection scope of the present application is obviously not limited to these specific embodiments. Those skilled in the art can make equivalent changes or replacements to the related technical features without departing from the principles of the present application, and the technical solutions after the changes or replacements will all fall within the protection scope of the present application.

Claims

1. A washing machine door detection circuit, characterized by, The door switch module, the control module and the detection module; wherein The door switch module is connected with the first power supply and the control module, and is used for outputting a signal of the first power supply to the control module when the door switch module is closed; The control module includes a plurality of parallel control branches, wherein the control branch includes a first control switch, the first end of the first control switch is connected with the second power supply, the second end of the first control switch in the control branch is connected with the first end of the first control switch in the adjacent control branch, and the second end of the first control switch in the tail control branch is connected with the detection module, and the control branch is used for controlling the first control switch to be turned on in response to the signal of the first power supply; The detection module is used for outputting a first signal in response to the signal of the second power supply, and the first signal represents that the washing machine door is closed; The door switch module includes a second door switch module, the second door switch module includes a door lock switch, a first optocoupler module and a second optocoupler module; The positive emission end of the first optocoupler module is connected with the live wire of the alternating mains power supply, the negative emission end of the first optocoupler module is connected with the positive emission end of the second optocoupler module, the negative emission end of the second optocoupler module is connected with the first end of the door lock switch, and the second end of the door lock switch is connected with the ground wire of the alternating mains power supply; The positive receiving end of the first optocoupler module is connected with the fourth power supply, the negative receiving end of the first optocoupler module is connected with the positive receiving end of the second optocoupler module, and the negative receiving end of the second optocoupler module is connected with the control module. The door switch module includes a first door switch module, the first door switch module includes a door switch, a first impedance and a second impedance; 2. The washing machine door detection circuit according to claim 1, characterized in that, The first end of the door switch is connected with the third power supply, the second end of the door switch is connected with the first end of the first impedance and the first end of the second impedance, the second end of the first impedance is connected with the control module and the ground, and the second end of the second impedance is grounded. The second door switch module further includes a third impedance, a first diode, a fourth impedance and a second diode; 3. The washing machine door detection circuit according to claim 1, characterized in that, The anode of the first diode is connected with the live wire of the alternating mains power supply, and the cathode is connected with the first end of the third impedance; the second end of the third impedance is connected with the positive emission end of the first optocoupler module; The first end of the fourth impedance is connected with the negative receiving end of the second optocoupler module, the second end of the fourth impedance is connected with the anode of the second diode; and the cathode of the second diode is connected with the control module. The control branch further includes a second control switch, a third diode, a fifth impedance and a sixth impedance; 4. The washing machine door detection circuit according to claim 1, characterized in that, The anode of the third diode is connected with the door switch module, the cathode of the third diode is connected with the first end of the fifth impedance; the second end of the fifth impedance is connected with the first end of the sixth impedance and the control end of the second control switch, and the second end of the sixth impedance is grounded; The first end of the second control switch is connected with the control end of the first control switch and the second power supply, and the second end of the second control switch is grounded. The control branch further includes a seventh impedance and an eighth impedance; 5. The washing machine door detection circuit according to claim 4, characterized in that, ​ The first end of the seventh impedance is connected to the first end of the second control switch, and the second end of the seventh impedance is connected to the control end of the first control switch and the first end of the eighth impedance; and the second end of the eighth impedance is connected to the first end of the first control switch.

6. The washing machine door detection circuit according to claim 4, characterized in that, The control branch further comprises a ninth impedance, a tenth impedance and an eleventh impedance. The first end of the ninth impedance is connected to the first end of the second control switch and the second end of the tenth impedance, and the first end of the tenth impedance is connected to the second power supply. The second end of the ninth impedance is connected to the control end of the first control switch and the first end of the eleventh impedance, and the second end of the eleventh impedance is connected to the first end of the first control switch.

7. The washing machine door detection circuit according to claim 4, characterized in that, The control module further comprises a first capacitor. The first end of the first capacitor is connected to the anode of the third diode in each control branch, and the second end of the first capacitor is grounded.

8. The washing machine door detection circuit according to any one of claims 1-7, characterized in that, The detection module comprises a plurality of detection branches, and each detection branch comprises a detection switch; wherein the control ends of the detection switches in adjacent detection branches are connected and connected to a relay power supply. The control end of the detection switch in the detection branch is connected to the control module, the first end of the detection switch is connected to a corresponding detection signal and a fourth power supply, and the second end of the detection switch is grounded.

9. The washing machine door detection circuit according to claim 8, characterized in that, The detection branch further comprises a voltage reduction resistor, a first shunt resistor and a second shunt resistor. The first end of the voltage reduction resistor is connected to the control module, the second end of the voltage reduction resistor is connected to the first end of the first shunt resistor and the first end of the second shunt resistor; the second end of the first shunt resistor is connected to the control end of the detection switch; and the second end of the second shunt resistor is connected to the second end of the detection switch.

10. The washing machine door detection circuit according to claim 8, characterized in that, The detection branch further comprises a second pull-up resistor, a fourth current limiting resistor and a second capacitor. The first end of the second pull-up resistor is connected to the fourth power supply, and the second end of the second pull-up resistor is connected to the first end of the detection switch; the first end of the fourth current limiting resistor is connected to the second end of the second pull-up resistor, the second end of the fourth current limiting resistor is connected to the first end of the second capacitor and the corresponding detection signal of the detection switch, and the second end of the second capacitor is grounded.

11. A laundry machine characterized by It comprises: The washing machine door detection circuit, the microprocessor and the overload protection module according to any one of claims 1-9; wherein the overload protection module comprises a protection switch and a system main relay; The microprocessor is connected to the washing machine door detection circuit; the control end of the system main relay is connected to the first end of the protection switch, the second end of the protection switch is grounded; and the control end of the protection switch is connected to the microprocessor.

12. A laundry washing machine according to Claim 11, characterized in that The overload protection module further comprises a twelfth impedance and a thirteenth impedance. The first end of the twelfth impedance is connected to the microprocessor, the second end of the twelfth impedance is connected to the control end of the protection switch and the first end of the thirteenth impedance, and the second end of the thirteenth impedance is grounded.

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