Washing machine control device

Abstract

The present invention discloses a washing machine control device, including a detection unit and a control unit. The detection unit includes a balance detection module, a state detection module and a detection output port, and the balance detection module and the state detection module are both connected to the detection output port; the balance detection module is used to perform balance detection on the washing machine barrel and generate a balance detection signal; the state detection module is connected to the AC motor and is used to perform state detection on the AC motor and generate a state detection signal; the detection output port is used to output a detection signal, and the detection signal is one of a balance detection signal and a state detection signal; the control unit is connected to the detection output port and is used to control the working mode of the washing machine according to the detection signal and control the working state of the AC motor. The present invention can not only perform balance detection on the washing machine barrel, but also perform state detection on the AC motor and complete closed-loop control of the AC motor, thereby improving the reliability of the AC motor control and the safety of the system.

Description

Technical Field

[0001] The present invention relates to the field of electronic technology, and in particular to a washing machine control device. Background Art

[0002] AC motors are one of the most widely used devices in the electromechanical industry and are the power source for other electromechanical equipment. AC motors can be used in electronic equipment, machinery, transmission and other fields. The research on their driving technology and detection technology has never stopped. How to obtain more stable and precise control and feedback detection in the application field has always been the main research direction.

[0003] At present, AC motors are used in various household appliances, such as washing machines, range hoods, refrigerators, etc.

[0004] In the prior art, the control device of the washing machine cannot perform balance detection on the washing machine drum, and most of the AC motors used in the washing machine adopt non-closed-loop control, that is, there is no feedback link control in the control system of the AC motor, and the reliability of the AC motor control and the safety of the system are very low. Summary of the invention

[0005] Based on this, it is necessary to provide a washing machine control device that can perform balance detection on the washing machine drum and use closed-loop control on the AC motor used in the washing machine to improve the reliability of AC motor control and the safety of the system.

[0006] A technical means adopted by the present invention is: providing a washing machine control device, the control device comprising: a detection unit and a control unit;

[0007] The detection unit includes a balance detection module, a state detection module and a detection output port, and the balance detection module and the state detection module are both connected to the detection output port;

[0008] The balance detection module is used to perform a balance detection on the washing machine drum and generate a balance detection signal;

[0009] The state detection module is connected to the AC motor and is used to detect the state of the AC motor and generate a state detection signal, wherein the state detection signal is one of a forward and reverse rotation detection signal or a stall detection signal;

[0010] The detection output port is used to output a detection signal, wherein the detection signal is one of the balance detection signal and the state detection signal;

[0011] The control unit is connected to the detection output port, and is used to control the working mode of the washing machine or the working state of the AC motor according to the detection signal output by the detection output port.

[0012] Due to the adoption of the above technical solution, the washing machine control device provided by the present invention includes a detection unit and a control unit. The detection unit includes a balance detection module, a state detection module and a detection output port, and the balance detection module and the state detection module are both connected to the detection output port; the present invention combines the balance detection module and the state detection module, so that it can not only perform balance detection on the washing machine drum, but also perform state detection on the AC motor. The control unit controls the working mode of the washing machine according to the balance detection signal output by the detection output port, or controls the working state of the AC motor according to the state detection signal output by the detection output port. The structure is simple and the cost is low, and only one detection output port is needed to output the balance detection signal or the state detection signal to the control unit, thus saving the resources of the control unit. The present invention uses the detection unit to detect the state of the AC motor, and outputs the state of the AC motor to the control unit through the detection output port. The control unit controls the working state of the AC motor according to the state detection signal output by the detection output port, thereby realizing the complete closed-loop control of the AC motor. Compared with the ordinary non-closed-loop AC motor control, the reliability of the AC motor control and the safety of the system are greatly improved. BRIEF DESCRIPTION OF THE DRAWINGS

[0013] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0014] in:

[0015] Figure 1 FIG. 1 is a schematic diagram of the structure of a washing machine control device in one embodiment. Figure 1 ;

[0016] Figure 2 FIG. 1 is a schematic diagram of the structure of a washing machine control device in one embodiment. Figure 2 ;

[0017] Figure 3 FIG. 1 is a schematic diagram of the structure of a washing machine control device in one embodiment. Figure 3 ;

[0018] Figure 4 is a circuit schematic diagram of a detection unit in one embodiment;

[0019] Figure 5 is a circuit schematic diagram of a driving unit in one embodiment;

[0020] Figure 6FIG. 4 is a circuit schematic diagram of a control unit in an embodiment.

[0021] In the figure: 1. detection unit; 2. control unit; 3. drive unit; 4. AC motor; 11. balance detection module; 12. status detection module; 13. detection output port; 31. forward drive branch; 32. reverse drive branch; 111. balance detection switch; 121. isolation feedback circuit; 122. rectification circuit; 311. forward drive module; 312. forward controllable switch; 321. reverse drive module; 322. reverse controllable switch. DETAILED DESCRIPTION

[0022] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0023] The terms "first", "second", etc. (if any) in the specification and claims and the above drawings are used to distinguish similar parts, and are not necessarily used to describe a specific order or sequence. It should be understood that the terms used in this way can be interchanged where appropriate, so that the embodiments of the present application described herein can be implemented in an order other than that illustrated herein.

[0024] The present invention provides a washing machine control device. In one embodiment, Figure 1 As shown, the washing machine control device may include a detection unit 1 and a control unit 2; the detection unit 1 may include a balance detection module 11, a state detection module 12 and a detection output port 13, and the balance detection module 11 and the state detection module 12 are both connected to the detection output port 13; the balance detection module 11 may be used to perform balance detection on the washing machine drum and generate a balance detection signal; the state detection module 12 may be connected to the AC motor 4, and is used to perform state detection on the AC motor 4 and generate a state detection signal, and the state detection signal is one of a forward and reverse detection signal or a stall detection signal; the detection output port 13 may be used to output a detection signal, and the detection signal is one of the balance detection signal and the state detection signal; the control unit 2 may be connected to the detection output port 13, and is used to control the working mode of the washing machine or the working state of the AC motor 4 according to the detection signal output by the detection output port 13.

[0025] The washing machine control device provided in this embodiment can perform balance detection on the washing machine drum and state detection on the AC motor 4 by combining the balance detection module 11 and the state detection module 12, wherein the state detection can include forward and reverse rotation detection of the AC motor 4, and detection of whether a stall occurs, with a simple structure and low cost, and only needs to output the detection signal to the control unit 2 through one detection output port 13, thus saving resources of the control unit 2. In this embodiment, the detection unit 1 is used to detect the state of the AC motor 4, and the state of the AC motor 4 is output to the control unit 2 through the detection output port 13. The control unit 2 controls the working state of the AC motor 4 according to the state detection signal output by the detection output port 13, thereby realizing a complete closed-loop control of the AC motor 4. Compared with the ordinary non-closed-loop AC motor control, the reliability of the control of the AC motor 4 and the safety of the system are greatly improved.

[0026] In one embodiment, the detection unit 1 performs time-sharing detection on the washing machine drum and the AC motor 4; when the control unit 2 controls the AC motor 4 to stop rotating, the detection unit 1 performs a balance detection on the washing machine drum; the control unit 2 determines whether the washing machine drum is balanced based on the detection signal to control the balance mode of the washing machine; when the washing machine drum is balanced, the detection unit 1 performs a state detection on the AC motor 4; the control unit 2 determines whether the AC motor is in forward rotation, reverse rotation or stalled rotation based on the forward control signal and reverse control signal output by the control unit 2 and the detection signal to control the working state of the AC motor 4.

[0027] In one embodiment, the control unit 2 is used to control the washing machine to enter a normal working mode when it is determined that the washing machine drum is balanced according to the detection signal; the control unit is used to control the washing machine to enter a balance adjustment mode when it is determined that the washing machine drum is unbalanced according to the detection signal.

[0028] In one embodiment, the control unit 2 is used to control the forward rotation speed of the AC motor 4 through the forward rotation control signal when it is determined that the AC motor 4 is rotating forward according to the detection signal; the control unit 2 is used to control the reverse rotation speed of the AC motor 4 through the reverse rotation control signal when it is determined that the AC motor 4 is reversed according to the detection signal; the control unit 2 is used to control the AC motor 4 to stop rotating when it is determined that the AC motor 4 is stalled according to the detection signal.

[0029] That is to say, the control unit 2 can be used to control the washing machine to enter a normal operating mode when the detection unit 1 detects that the washing machine drum is balanced; the control unit 2 can be used to control the washing machine to enter a balance adjustment mode when the detection unit 1 detects that the washing machine drum is unbalanced; the control unit 2 can be used to control the forward rotation speed of the AC motor 4 when the detection unit 1 detects that the AC motor 4 is rotating forward; the control unit 2 can be used to control the reverse rotation speed of the AC motor 4 when the detection unit 1 detects that the AC motor 4 is reversing; the control unit 2 can be used to control the AC motor 4 to stop rotating when the detection unit 1 detects that the AC motor 4 is stalled.

[0030] Exemplarily, before the washing machine enters the normal working mode, the laundry is put into the washing machine drum. If the detection unit 1 detects that the washing machine is unbalanced, that is, the laundry put into the washing machine drum causes the washing machine drum to be unbalanced, the detection unit 1 outputs a balance detection signal to the control unit 2, and the control unit 2 controls the washing machine to enter a balance adjustment mode until the washing machine drum is balanced; if the detection unit 1 detects that the washing machine is balanced, that is, the laundry put into the washing machine drum does not cause the washing machine drum to be unbalanced, the detection unit 1 outputs a balance detection signal to the control unit 2, and the control unit 2 controls the washing machine to enter the normal working mode.

[0031] In this embodiment, before the washing machine enters the normal working mode, that is, when the control unit 2 controls the AC motor 4 to stop rotating, the detection unit 1 performs a balance detection on the washing machine drum and controls the balance mode of the washing machine, thereby ensuring that the washing machine drum is balanced before the washing machine enters the normal working mode, avoiding the washing machine being damaged when the washing machine drum enters the normal working mode of the washing machine in an unbalanced state, and greatly improving the safety and reliability of the washing machine control system.

[0032] Exemplarily, after the washing machine enters the normal working mode, the control unit 2 outputs a control signal to control the rotation of the AC motor 4, wherein the control signal includes a forward control signal and a reverse control signal. At the same time, the detection unit 1 detects the state of the AC motor 4, and outputs a detection signal to the control unit 2 through the detection output port 13. Further, when the detection unit 1 detects that the AC motor 4 is rotating forward, the control unit 2 can control the forward speed of the AC motor 4 by adjusting the control signal. When the detection unit 1 detects that the AC motor 4 is reversing, the control unit 2 can control the reversing speed of the AC motor 4 by adjusting the control signal. When the detection unit 1 detects that the AC motor 4 is blocked, the control unit 2 can control the AC motor 4 to stop rotating by adjusting the control signal.

[0033] In this embodiment, after the washing machine enters the normal working mode, that is, when the washing machine drum is balanced, the washing machine control device can detect the state of the AC motor 4 and control the working state of the AC motor 4. By controlling the forward speed and reverse speed of the AC motor 4, the AC motor 4 of the washing machine can be ensured to rotate at an appropriate speed to avoid the AC motor 4 rotating too slowly and thus failing to achieve the washing effect, or to avoid the AC motor 4 rotating too fast and thus damaging the washing machine. By performing a stall detection on the AC motor 4, the control unit controls the AC motor 4 to stop rotating when it is determined that the AC motor 4 is stalled, so as to protect the AC motor 4 and related components from being damaged, thereby greatly improving the safety and reliability of the washing machine control system and ensuring that the washing machine can achieve a good washing effect when it is working.

[0034] In one embodiment, the washing machine control device may further include a power supply, which is used to supply power to the washing machine control device. The power supply may provide a power supply voltage for the washing machine control device, such as +3.3V, +5V, +12V, and of course, the power supply voltage may also be other voltage values ​​required for adaptation. The power supply has a power supply terminal and an isolated ground terminal.

[0035] In one embodiment, Figure 6As shown, the control unit 2 uses a single-chip microcomputer U4, and the single-chip microcomputer U4 can be FREESCALE or MC9S08AC16CFGE. Of course, the single-chip microcomputer U4 can also use other models. The single-chip microcomputer U4 is powered by +5V DC. The first capacitor C11 and the second capacitor C12 are the power supply filter capacitors of the single-chip microcomputer U4. The I / O port of the single-chip microcomputer U4 outputs the forward control signal Ctrl CW, the reverse control signal Ctrl CCW, and receives the input detection signal Motor sensor. Further, the 32nd pin of the single-chip microcomputer U4 receives the detection signal Motorsensor, the 43rd pin of the single-chip microcomputer U4 outputs the forward control signal Ctrl CW, and the 40th pin of the single-chip microcomputer U4 outputs the reverse control signal Ctrl CCW. Further, when the washing machine enters the normal working mode, the I / O port of the single-chip microcomputer U4 outputs the forward control signal Ctrl CW and the reverse control signal Ctrl CCW. Of course, the control unit 2 may also adopt DSP, FPGA, etc., as well as other control modules with equivalent functions, and this application does not make any special limitation.

[0036] In this embodiment, the single-chip microcomputer U4 uses one I / O port to realize the balance detection of the washing machine drum, the forward and reverse detection of the AC motor 4, and the detection of whether it is blocked, which saves the resources of the single-chip microcomputer U4. The single-chip microcomputer U4 can control the rotation speed of the AC motor 4 by outputting the forward control signal Ctrl CW and the reverse control signal Ctrl CCW, ensuring that the AC motor rotates at a suitable speed to achieve a good washing effect, and when the AC motor 4 is detected to be blocked, the AC motor 4 is controlled to stop rotating to protect the AC motor 4 and related components from being damaged, which greatly improves the safety and reliability of the washing machine control system and ensures that the washing machine can achieve a good washing effect when it works normally.

[0037] In one embodiment, Figure 3As shown, the detection signal Motor sensor has a first state and a second state, and the level logic states of the first state and the second state are opposite; the balance detection module 11 may include a balance detection switch 111, and the balance detection switch 111 is a mechanical switch. Further, the balance detection switch 111 can be used to perform balance detection on the washing machine barrel according to the plane inclination angle and / or center of gravity change of the washing machine barrel; the balance detection switch 111 can be placed next to the washing machine barrel; when the balance detection switch 111 detects that the washing machine barrel is balanced, the balance detection switch 111 is disconnected; when the balance detection switch 111 detects that the washing machine barrel is unbalanced, the balance detection switch 111 is closed. Further, when the balance detection switch 111 is closed, the detection signal output by the detection output port 13 is in a first state, and the control unit 2 determines that the washing machine drum is in an unbalanced state based on the detection signal Motorsensor; when the balance detection switch 111 is disconnected, the detection signal Motorsensor output by the detection output port 13 is in a second state, and the control unit 2 determines that the washing machine drum is in a balanced state based on the detection signal Motorsensor.

[0038] Further, the first state is a low logic level, and the second state is a high logic level.

[0039] Specifically, the balance detection switch 111 can be placed on the side of the washing machine barrel, or on the bottom of the washing machine barrel. This application does not make any special restrictions, as long as the switch contacts of the balance detection switch 111 face the washing machine barrel. Furthermore, if the washing machine barrel shakes with a large amplitude, the washing machine barrel will hit the switch contacts of the balance detection switch 111, and the balance detection switch 111 will be closed, and then the detection unit 1 will output a balance detection signal to the control unit 2. The control unit 2 controls the washing machine to enter a balance adjustment mode according to the balance detection signal output by the detection unit 1 until the washing machine barrel is balanced.

[0040] In this embodiment, the control unit 2 can determine the state of the washing machine drum according to the detection signal Motor sensor outputted from the detection output port, and can control the balance mode of the washing machine according to the state of the washing machine drum. When it is detected that the washing machine is unbalanced, the control unit 2 controls the washing machine to enter the balance adjustment mode to ensure that the washing machine enters the normal working mode under the balanced condition, which greatly improves the safety and reliability of the washing machine control system and ensures that the washing machine can achieve good washing effects when it is working normally.

[0041] In one embodiment, reference Figure 4As shown, the balance detection module 11 may also include a current limiting resistor R70 and a clamping diode D20. In the figure, CON4 is an interface of the balance detection switch 111, which is used to connect the balance detection switch 111. The current limiting resistor R70 is a current limiting resistor from the detection signal Motor sensor to the single-chip computer U4, and the clamping diode D20 is a Schottky diode, which acts as a clamp to ensure that the signal of the detection signal Motor sensor input to the single-chip computer does not exceed the power supply voltage, thereby protecting the I / O port of the single-chip computer.

[0042] For example, reference Figure 4 As shown, the first end of the interface CON4 of the balance detection switch 111 is connected to the isolation ground terminal, the second end of the interface CON4 of the balance detection switch 111 is connected to the first end of the current limiting resistor R70, the second end of the current limiting resistor R70 is connected to the detection output port 13 and the common end of the clamping diode D20, the positive end of the clamping diode D20 is connected to the isolation ground terminal, and the negative end of the clamping diode D20 receives +5V.

[0043] Specifically, the working principle of washing machine drum balance detection is: Figure 4 and Figure 5 As shown, when the control unit 2 controls the AC motor 4 to stop rotating, that is, the forward control signal Ctrl CW and the reverse control signal Ctrl CCW output by the control unit 2 are both at low logic levels, the state detection module 12 only performs balance detection on the washing machine drum.

[0044] Specifically, Figure 4 As shown, if the balance detection switch 111 is disconnected, the balance detection module 11 is in a disconnected state. At this time, since the detection output port 13 is connected to the common end of the clamping diode D20, the potential of the detection signal Motor sensor output by the detection output port 13, that is, the balance detection signal, is forced to be pulled to +5V, that is, a high logic level. The control unit 2 determines that the washing machine drum is in a balanced state, and the control unit 2 controls the washing machine to enter a normal working mode.

[0045] Specifically, Figure 4As shown, if the balance detection switch 111 is closed, the balance detection module 11 is in the on state. At this time, since the detection output port 13 is connected to the common end of the clamping diode D20, the potential of the detection signal Motor sensor output by the detection output port 13, that is, the balance detection signal, is forced to be pulled low, that is, when it is a low logic level, the control unit 2 determines that the washing machine drum is in an unbalanced state, and the control unit 2 controls the washing machine to enter the balance adjustment mode to adjust the balance of the washing machine drum until the balance detection signal is a high logic level to balance the washing machine drum.

[0046] This embodiment can complete the balance detection of the washing machine drum by adopting a balance detection switch 111, a current limiting resistor R70 and a clamping diode D20, and the circuit is simple and the cost is low.

[0047] Furthermore, the relationship between the forward control signal Ctrl CW, the reverse control signal Ctrl CCW, the balance detection switch 111, the detection signal Motor sensor and the detection result can be seen in Table 1.

[0048] In one embodiment, Figure 2 and Figure 3 As shown, the forward control signal Ctrl CW and the reverse control signal Ctrl CCW both have a first state and a second state, and the level logic states of the first state and the second state are opposite; the control device may also include a driving unit 3, and the driving unit 3 may include a forward driving branch 31 and a reverse driving branch 32 that are independent of each other, and the forward driving branch 31 and the reverse driving branch 32 are both connected between the control unit 2 and the AC motor 4, and the forward driving branch 31 is used to drive the AC motor 4 to rotate forward according to the control signal output by the control unit, and the reverse driving branch 32 is used to drive the AC motor 4 to rotate reversely according to the control signal output by the control unit 2.

[0049] Further, the control unit 2 can be used to output a forward control signal Ctrl CW in a first state, so that the forward drive branch 31 is turned off and output a reverse control signal Ctrl CCW in a second state, so that the reverse drive branch 32 is turned on, so as to control the reverse rotation of the AC motor 4; the control unit 2 can be used to output a forward control signal Ctrl CW in a second state, so that the forward drive branch 31 is turned on and output a reverse control signal Ctrl CW in a first state, so that the reverse drive branch 32 is turned off, so as to control the forward rotation of the AC motor 4; the control unit 2 is used to output a forward control signal Ctrl CW and a reverse control signal Ctrl CCW in a first state, so that both the forward drive branch 31 and the reverse drive branch 32 are turned off, so as to control the AC motor 4 to stop rotating. Further, the first state is a low logic level, and the second state is a high logic level.

[0050] This embodiment controls the on and off of the forward drive branch 31 and the reverse drive branch 32 according to the forward control signal Ctrl CW and the reverse control signal Ctrl CCW, thereby controlling the forward or reverse rotation of the AC motor 4, and when the AC motor 4 is blocked, the AC motor 4 is controlled to stop rotating, thereby protecting the AC motor 4 and related components from damage.

[0051] In one embodiment, Figure 3 and Figure 5 As shown, the forward drive branch 31 may include a forward drive module 311 and a forward controllable switch 312, one end of the forward drive module 311 is connected to the control unit 2, the other end of the forward drive module 311 is connected to one end of the forward controllable switch 312, and the other end of the forward controllable switch 312 is connected to the AC motor 4; when the forward control signal Ctrl CW is in the first state, the forward controllable switch 312 is turned off, so that the forward drive branch 31 is turned off, and when the forward control signal Ctrl CW is in the first state, the forward controllable switch 312 is turned off, so that the forward drive branch 31 is turned off. When CW is in the second state, the forward controllable switch 312 is turned on, so that the forward drive branch 31 is turned on; the reverse drive branch 32 may include a reverse drive module 321 and a reverse controllable switch 322, one end of the reverse drive module 321 is connected to the control unit 2, the other end of the reverse drive module 321 is connected to one end of the reverse controllable switch 322, and the other end of the reverse controllable switch 322 is connected to the AC motor 4; when the reverse control signal is in the first state, the reverse controllable switch 322 is turned off, so that the reverse drive branch 32 is turned off, and when the reverse control signal Ctrl CCW is in the second state, the reverse controllable switch 322 is turned on, so that the reverse drive branch 32 is turned on.

[0052] In this embodiment, the forward rotation or reverse rotation of the AC motor 4 is controlled by controlling the on and off of the forward rotation controllable switch 312 and the reverse rotation controllable switch 322, and the control is simple and convenient.

[0053] In one embodiment, Figure 3 and Figure 4 As shown, the state detection module 12 may include an isolation feedback circuit 121, the input end of the isolation feedback circuit 121 is connected to the AC motor 4, and the output end of the isolation feedback circuit 121 is connected to the detection output port 13; when the forward control signal Ctrl CW output by the control unit 2 is in the first state and the reverse control signal Ctrl CCW is in the second state, and the isolation feedback circuit 121 is turned on, the detection signal Motor sensor output by the detection output port 13 is in the first state, and the control unit 2 determines that the AC motor 4 is reversed; when the forward control signal Ctrl CW output by the control unit 2 is in the second state and the reverse control signal Ctrl CCW is in the first state, and the isolation feedback circuit 121 is turned off, the detection signal Motor sensor output by the detection output port is in the second state, and the control unit 2 determines that the AC motor 4 is forward; when the forward control signal Ctrl CW output by the control unit 2 is in the first state and the reverse control signal Ctrl CCW is in the second state, and the isolation feedback circuit 121 is turned off, the detection signal Motor sensor output by the detection output port is in the second state, and the control unit 2 determines that the AC motor 4 is forward; when the forward control signal Ctrl CW output by the control unit 2 is in the first state and the reverse control signal Ctrl CCW is in the second state, and the isolation feedback circuit 121 is turned off, the detection signal Motor sensor output by the detection output port is in the second state, and the control unit 2 determines that the AC motor 4 is forward. The sensor is in the second state, and the control unit 2 determines that the AC motor 4 is stalled. Further, the first state is a low logic level, and the second state is a high logic level.

[0054] In this embodiment, the control unit adopts an isolated feedback circuit 121 and determines the state of the AC motor 4 according to the states of the forward control signal CtrlCW, the reverse control signal Ctrl CCW and the detection signal Motor sensor output by the detection output port, thereby realizing the state feedback detection function of the AC motor 4, so that the motor control of the washing machine realizes a complete closed loop, greatly improving the reliability of the AC motor control and the safety of the system, and by adopting an isolation scheme, the washing machine AC motor control system is safer and more reliable.

[0055] In one embodiment, Figure 4 As shown, the isolated feedback circuit 121 may include a photocoupler OP1 , a control end of the photocoupler OP1 is connected to the AC motor 4 , and a feedback output end of the isolated feedback circuit 121 is connected to the detection output port 13 .

[0056] In one embodiment, the isolation feedback circuit 121 may also include a first resistor R20, a second resistor R23, a third resistor R11, a first transistor Q4, a fourth resistor R19 and a first filter capacitor C27. Specifically, the collector of the photosensitive transistor inside the photocoupler OP1 receives the power supply voltage, i.e., +5V, and is connected to the first end of the second resistor R23 and the collector of the first transistor Q4 through the first resistor R20, the second end of the second resistor R23 is connected to the detection output port 13, and is connected to the isolation ground terminal via the first filter capacitor C27; the emitter of the photosensitive transistor inside the photocoupler OP1 is connected to the base of the first transistor Q4 through the third resistor R11, and the base of the first transistor Q4 is connected to the emitter of the first transistor Q4 through the fourth resistor R19 and is connected to the isolation ground terminal. Among them, the third resistor R11 is the current limiting resistor of the base of the first transistor Q4, the fourth resistor R19 is the pull-down resistor of the base of the first transistor Q4, the first resistor R20 is the pull-up resistor of the first transistor Q4, and the second resistor R23 is the current limiting resistor input by the microcontroller U4.

[0057] In this embodiment, a photoelectric coupler is used to isolate the AC motor and the status output, making the washing machine AC motor control system safer and more reliable, and the forward rotation, reverse rotation and stall detection of the AC motor can be performed. The circuit is simple and the cost is low, and a complete closed-loop control of the AC motor is achieved. Compared with the ordinary non-closed-loop AC motor control, the reliability of the AC motor control and the safety of the system are greatly improved.

[0058] In one embodiment, Figure 3 As shown, the state detection module 12 may also include a rectifier circuit 122, a first end of the rectifier circuit 122 may be connected to the AC motor 4, a second end of the rectifier circuit 122 and the AC motor 4 are both connected to a first end of the isolation feedback circuit 121, and a second end of the isolation feedback circuit 121 is connected to the detection output port 13; the rectifier circuit 122 may be used to rectify the AC motor voltage signal to obtain a first rectified voltage signal; the isolation feedback circuit 121 may be used to output the state detection signal after electrically isolating and performing state feedback detection on the first rectified voltage signal and the AC motor voltage signal.

[0059] For example, reference Figure 4As shown, the rectifier circuit 122 may include a rectifier diode D12 and a fifth resistor R96. The cathode of the rectifier diode D12 is connected to the AC motor 4 for receiving the voltage signal CW of the AC motor 4, the anode of the rectifier diode D12 is connected to the first end of the fifth resistor R96, and the second end of the sixth resistor R96 is connected to the isolation feedback circuit 121. The fifth resistor R96 is a current limiting resistor. Furthermore, the anode of the light-emitting diode inside the photocoupler OP1 receives the input voltage signal CCW of the AC motor 4, and the cathode of the light-emitting diode inside the photocoupler OP1 is connected to the second end of the fifth resistor R96.

[0060] Specifically, the working principle of the reverse detection of the AC motor 4 is as follows: Figure 4 and Figure 5 As shown, when the washing machine drum is balanced, that is, when the balance detection switch 111 is disconnected, when the forward control signal Ctrl CW output by the control unit 2 is at a low logic level and the reverse control signal Ctrl CCW is at a high logic level, the emitter of the phototransistor inside the photocoupler OP1 is turned on, and at the same time, the collector and emitter of the phototransistor inside the photocoupler OP1 are turned on, so that the base of the first transistor Q4 is connected to the +5V voltage, the first transistor Q4 is turned on, and the test point TP149 becomes a low logic level, and the detection signal Motor sensor, that is, the status detection signal, becomes a low logic level and is output to the control unit 2, and the control unit 2 determines that the AC motor 4 is reversed.

[0061] Specifically, the working principle of the forward rotation detection of the AC motor 4 is as follows: Figure 4 and Figure 5 As shown, when the washing machine drum is balanced, that is, when the balance detection switch 111 is disconnected, when the forward control signal Ctrl CW output by the control unit 2 is at a high logic level and the reverse control signal Ctrl CCW is at a low logic level, the emitter of the phototransistor inside the photocoupler OP1 is cut off, and at the same time, the collector and emitter of the phototransistor inside the photocoupler OP1 are cut off, so that the +5V voltage is output through the first resistor R20 and the second resistor R23, the test point TP144 becomes a high logic level, and the detection signal Motor sensor, that is, the state detection signal, becomes a high logic level and is output to the control unit 2, and the control unit 2 determines that the AC motor 4 rotates forward.

[0062] Specifically, the working principle of the AC motor 4 stall detection is as follows: Figure 4 and Figure 5As shown, when the washing machine drum is balanced, that is, when the balance detection switch 111 is disconnected, when the forward control signal Ctrl CW output by the control unit 2 is at a low logic level and the reverse control signal Ctrl CCW is at a high logic level, if the AC motor 4 is blocked, the reverse coil of the AC motor 4 is approximately short-circuited, so that the voltage signal CW of the AC motor 4 is at a high logic level, the photocoupler OP1 does not work, the first transistor Q4 is turned off, and the test point TP144 becomes a high logic level, then the control unit 2 can determine that the forward coil of the AC motor 4 is open or the reverse coil is blocked and short-circuited. Further, the control unit 2 can set both the forward control signal Ctrl CW and the reverse control signal Ctrl CCW to a low logic level, so that the AC motor 4 stops rotating, so as to stop controlling the AC motor 4, and protect the AC motor 4, the first thyristor SCR5 and the second thyristor SCR6 from being damaged.

[0063] Furthermore, the relationship between the forward control signal Ctrl CW, the reverse control signal Ctrl CCW, the balance detection switch 111, the detection signal Motor sensor and the detection result can be seen in Table 1.

[0064] In this embodiment, the detection unit 1 detects the state of the AC motor 4, and outputs the state of the AC motor 4 to the control unit 2 through the detection output port 13. The control unit 2 controls the working state of the AC motor 4 according to the detection signal output by the detection output port 13, thereby realizing a complete closed-loop control of the AC motor 4. The reliability of the AC motor control and the safety of the system are greatly improved. In addition, the detection unit 1 combines the balance detection module 11 and the state detection module 12 to realize the balance detection of the washing machine drum and the forward, reverse and blocked rotation detection of the AC motor 4 in one circuit, and the circuit is simple and the cost is low. In addition, the detection unit 1 outputs the detection signal to the control unit 2 only through one detection output port 13, which saves the resources of the control unit 2. In addition, the state detection module 12 adopts an isolation scheme, making the washing machine control device safer and more reliable.

[0065] In one embodiment, reference Figure 5As shown, the reversing driving module 321 may include a first pull-up resistor R8, a first current limiting resistor R9, a first pull-down resistor R10, a second current limiting resistor R11, and a second triode TR1; the reversing controllable switch 322 may be a first thyristor SCR5, and of course may also be other switches that can receive a switch control signal and thus implement a switch operation. The second current limiting resistor R11 is a base current limiting resistor of the second triode TR1, the first pull-down resistor R10 is a base pull-down resistor of the second triode TR1, the first pull-up resistor R8 is a collector pull-up resistor of the second triode TR1, and the first current limiting resistor R9 is a collector current limiting resistor of the second triode TR1. Specifically, the first end of the second current limiting resistor R11 is connected to the control unit 2 for receiving the reversal control signal CtrlCCW, the second end of the second current limiting resistor R11 is connected to the base of the second transistor TR1, and is connected to the first end of the first pull-down resistor R10; the second end of the first pull-down resistor R10 is connected to the emitter of the second transistor TR1, and is connected to 0V; the collector of the second transistor TR1 is connected to the first end of the first current limiting resistor R9, the second end of the first current limiting resistor R9 is connected to the control electrode of the first thyristor SCR5, and is connected to the first end of the first pull-up resistor R8, the second end of the first pull-up resistor R8 receives 5V; the second electrode of the first thyristor SCR5 receives 5V, the first electrode of the first thyristor SCR5 is connected to the AC motor 4, and is used to output the voltage signal CCW of the AC motor 4.

[0066] This embodiment can realize the reverse drive control of the AC motor by only using one controllable switch, four resistors and one transistor. The circuit is simple, the cost is low, the control is simple and convenient, and the application field is wide.

[0067] In one embodiment, reference Figure 5As shown, the forward drive module 311 may include a second pull-up resistor R12, a third current limiting resistor R13, a second pull-down resistor R14, a fourth current limiting resistor R15 and a third triode TR2; the forward controllable switch 312 may be a second thyristor SCR6, and of course may also be other switches that can receive a switch control signal and thus implement switch operation. The fourth current limiting resistor R15 is the base current limiting resistor of the third triode TR2, the second pull-down resistor R14 is the base pull-down resistor of the third triode TR2, the second pull-up resistor R12 is the collector pull-up resistor of the third triode TR2, and the third current limiting resistor R13 is the collector current limiting resistor of the third triode TR2. Specifically, the first end of the fourth current limiting resistor R15 is connected to the control unit 2 for receiving the forward control signal Ctrl CW, the second end of the fourth current limiting resistor R15 is connected to the base of the third transistor TR2, and connected to the first end of the second pull-down resistor R14; the second end of the second pull-down resistor R14 is connected to the emitter of the third transistor TR2, and connected to 0V; the collector of the third transistor TR2 is connected to the first end of the third current limiting resistor R13, the second end of the third current limiting resistor R13 is connected to the control electrode of the second thyristor SCR6, and connected to the first end of the second pull-up resistor R12, the second end of the second pull-up resistor R12 receives 5V; the second electrode of the second thyristor SCR6 receives 5V, the first electrode of the second thyristor SCR6 is connected to the AC motor 4, and is used to output the voltage signal CW of the AC motor 4.

[0068] This embodiment can realize the forward drive control of the AC motor by only using one controllable switch, four resistors and one transistor. The circuit is simple, the cost is low, the control is simple and convenient, and the application field is wide.

[0069] Specifically, the working principle of the reverse control of the AC motor 4 is as follows: Figure 5 As shown, when the control unit 2 outputs the reverse control signal Ctrl CCW at a high logic level, the second transistor TR1 is turned on, the control pole of the first thyristor SCR5 is at a low logic level, the first thyristor SCR5 is fully turned on, and drives the AC motor 4 to reverse; and when the control unit 2 outputs the reverse control signal Ctrl CCW at a low logic level, the second transistor TR1 is turned off, the control pole of the first thyristor SCR5 is at a high logic level, the first thyristor SCR5 is turned off, and the AC motor 4 stops rotating. Further, the control unit 2 can input a required PWM signal, that is, by adjusting the duty cycle of the reverse control signal Ctrl CCW, the conduction angle of the first thyristor SCR5 can be adjusted, the speed of the AC motor 4 can be adjusted, and the reverse speed of the AC motor 4 can be controlled.

[0070] Specifically, the working principle of the forward rotation control of the AC motor 4 is as follows: Figure 5 As shown, when the control unit 2 outputs a forward rotation control signal Ctrl CW at a high logic level, the third transistor TR2 is turned on, the control pole of the second thyristor SCR6 is at a low logic level, and the second thyristor SCR6 is fully turned on to drive the AC motor 4 to rotate forward; and when the control unit 2 outputs a forward rotation control signal Ctrl CW at a low logic level, the third transistor TR2 is turned off, the control pole of the second thyristor SCR6 is at a high logic level, the second thyristor SCR6 is turned off, and the AC motor 4 stops rotating. Further, the control unit 2 can input a required PWM signal, that is, by adjusting the duty cycle of the forward rotation control signal Ctrl CW, the conduction angle of the second thyristor SCR6 can be adjusted, the AC motor 4 can be speed-regulated, and the forward rotation speed of the AC motor 4 can be controlled.

[0071] The device models and parameters in the embodiments of the present application can be appropriately adjusted according to actual needs and design requirements, and this application does not impose any limitations.

[0072] Furthermore, the washing machine control device provided in this embodiment can detect the state of the AC motor 4 and output a state detection signal to the control unit 2, and the control unit 2 controls the working state of the AC motor 4 based on the state detection signal. When the detection unit 1 detects that the AC motor 4 is rotating forward, the control unit 2 can adjust the duty cycle of the forward control signal Ctrl CW to control the forward speed of the AC motor 4, thereby realizing the forward closed-loop control of the AC motor 4. When the detection unit 1 detects that the AC motor 4 is rotating reversely, the control unit 2 can adjust the duty cycle of the reverse control signal Ctrl CCW to control the reverse speed of the AC motor 4, thereby realizing the reverse closed-loop control of the AC motor 4. Compared with the ordinary non-closed-loop AC motor control, the reliability of the AC motor control and the safety of the system are greatly improved.

[0073] Furthermore, the washing machine control device provided in this embodiment can perform balance detection on the washing machine drum and output a balance detection signal to the control unit 2. The control unit 2 controls the working mode of the washing machine based on the balance detection signal. When the detection unit 1 detects that the washing machine drum is balanced, the control unit 2 controls the washing machine to enter a normal working mode. When the detection unit 1 detects that the washing machine drum is unbalanced, the control unit 2 controls the washing machine to enter a balanced working mode until the washing machine drum is balanced, thereby realizing balance detection and control of the washing machine drum.

[0074] Furthermore, the washing machine control device provided in this embodiment can detect the forward rotation, reverse rotation and stall of the AC motor and output a state detection signal to the control unit 2. The control unit 2 determines whether the AC motor is in forward rotation, reverse rotation or stall based on the forward rotation control signal, reverse rotation control signal and state detection signal. The control unit 2 can also control the AC motor 4 according to the working state of the AC motor 4 to achieve full closed-loop control of the AC motor 4. When the detection unit 1 detects that the AC motor 4 is rotating forward, the control unit 2 can adjust the duty cycle of the forward rotation control signal Ctrl CW to control the forward rotation speed of the AC motor 4 to achieve forward closed-loop control of the AC motor 4. When the detection unit 1 detects that the AC motor 4 is rotating reversely, the control unit 2 can adjust the duty cycle of the reverse rotation control signal Ctrl CCW to control the reverse rotation speed of the AC motor 4 to achieve reverse closed-loop control of the AC motor 4. When the detection unit 1 detects that the AC motor 4 is stalled, the control unit 2 can set the forward control signal Ctrl CW and the reverse control signal Ctrl CCW to low logic levels to stop the AC motor 4 from rotating, so as to stop controlling the AC motor 4, thereby protecting the AC motor 4, the first thyristor SCR5 and the second thyristor SCR6 from damage. Compared with the ordinary non-closed-loop AC motor control, the reliability of the AC motor control and the safety of the system are greatly improved.

[0075] In the above embodiment, the relationship between the forward control signal Ctrl CW, the reverse control signal Ctrl CCW, the balance detection switch 111, the detection signal Motor sensor and the detection result is shown in Table 1.

[0076] Table 1: Truth table

[0077] Ctrl CW Ctrl CCW Balance detection switch Motor sensor Test results 0 0 disconnect H balance 0 0 closure L Non-equilibrium 0 1 disconnect L Reversal 1 0 disconnect H Forward 0 1 disconnect H Stall

[0078] The technical features of the above embodiments may be combined arbitrarily. To make the description concise, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0079] The above-mentioned embodiments only express several implementation methods of the present application, and the descriptions thereof are relatively specific and detailed, but they cannot be understood as limiting the scope of the present application. It should be pointed out that, for a person of ordinary skill in the art, several variations and improvements can be made without departing from the concept of the present application, and these all belong to the protection scope of the present application. Therefore, the protection scope of the present application shall be subject to the attached claims.

Claims

1. A washing machine control device, characterized in that: The control device comprises: a detection unit and a control unit; The detection unit includes a balance detection module, a state detection module and a detection output port, and the balance detection module and the state detection module are both connected to the detection output port; The balance detection module is used to perform a balance detection on the washing machine drum and generate a balance detection signal; The state detection module is connected to the AC motor and is used to detect the state of the AC motor and generate a state detection signal, wherein the state detection signal is one of a forward and reverse rotation detection signal and a stall detection signal; The detection output port is used to output a detection signal, wherein the detection signal is one of the balance detection signal and the state detection signal; The control unit is connected to the detection output port and is used to control the working mode of the washing machine or the working state of the AC motor according to the detection signal output by the detection output port; Wherein, when the washing machine drum is balanced, the detection unit detects the state of the AC motor; the control unit determines whether the AC motor is in forward rotation, reverse rotation or stalled rotation based on the forward rotation control signal and reverse rotation control signal output by the control unit and the detection signal, so as to control the working state of the AC motor; The forward control signal and the reverse control signal both have a first state and a second state, and the level logic states of the first state and the second state are opposite; The control device also includes: A driving unit, the driving unit comprising a forward drive branch and a reverse drive branch which are independent of each other, the forward drive branch and the reverse drive branch are both connected between the control unit and the AC motor, the forward drive branch is used to drive the AC motor to rotate forward according to a control signal output by the control unit, and the reverse drive branch is used to drive the AC motor to rotate reversely according to a control signal output by the control unit; The control unit is used to output a forward control signal of a first state to turn off the forward drive branch and output a reverse control signal of a second state to turn on the reverse drive branch to control the reverse rotation of the AC motor; The control unit is used to output a forward control signal of the second state to turn on the forward drive branch and output a reverse control signal of the first state to turn off the reverse drive branch to control the AC motor to rotate forward; The control unit is used to output a forward control signal and a reverse control signal in a first state, so that the forward drive branch and the reverse drive branch are both turned off, so as to control the AC motor to stop rotating.

2. The washing machine control device according to claim 1, characterized in that: The detection unit performs time-sharing detection on the washing machine tub and the AC motor; When the control unit controls the AC motor to stop rotating, the detection unit performs a balance detection on the washing machine tub; the control unit determines whether the washing machine tub is balanced based on the detection signal to control the balance mode of the washing machine.

3. The washing machine control device according to claim 2, characterized in that: The control unit is used to control the washing machine to enter a normal working mode when it is determined that the washing machine drum is balanced according to the detection signal; The control unit is used for controlling the washing machine to enter a balance adjustment mode when it is determined that the washing machine drum is unbalanced according to the detection signal.

4. The washing machine control device according to claim 2, characterized in that: The control unit is used to control the forward rotation speed of the AC motor through the forward rotation control signal when it is determined that the AC motor is rotating forward according to the detection signal; The control unit is used to control the reverse speed of the AC motor through the reverse control signal when it is determined that the AC motor is reversed according to the detection signal; The control unit is used for controlling the AC motor to stop rotating when it is determined that the AC motor is stalled according to the detection signal.

5. The washing machine control device according to any one of claims 2 to 4, characterized in that: The detection signal has a first state and a second state, and the level logic states of the first state and the second state are opposite; The balance detection module includes a balance detection switch; the balance detection switch is a mechanical switch, which is arranged beside the washing machine tub; When the balance detection switch is closed, the detection signal output by the detection output port is in a first state, and the control unit determines that the washing machine drum is in an unbalanced state according to the detection signal; When the balance detection switch is turned off, the detection signal output by the detection output port is in the second state, and the control unit determines that the washing machine drum is in a balanced state according to the detection signal.

6. The washing machine control device according to claim 1, characterized in that: The forward drive branch includes a forward drive module and a forward controllable switch, one end of the forward drive module is connected to the control unit, the other end of the forward drive module is connected to one end of the forward controllable switch, and the other end of the forward controllable switch is connected to the AC motor; when the forward control signal is in a first state, the forward controllable switch is turned off, so that the forward drive branch is turned off, and when the forward control signal is in a second state, the forward controllable switch is turned on, so that the forward drive branch is turned on; The reversing drive branch includes a reversing drive module and a reversing controllable switch, one end of the reversing drive module is connected to the control unit, the other end of the reversing drive module is connected to one end of the reversing controllable switch, and the other end of the reversing controllable switch is connected to the AC motor; when the reversing control signal is in a first state, the reversing controllable switch is turned off, so that the reversing drive branch is turned off, and when the reversing control signal is in a second state, the reversing controllable switch is turned on, so that the reversing drive branch is turned on.

7. The washing machine control device according to any one of claims 2 to 4, characterized in that: The state detection module comprises an isolation feedback circuit, the input end of the isolation feedback circuit is connected to the AC motor, and the output end of the isolation feedback circuit is connected to the detection output port; When the forward control signal output by the control unit is in the first state and the reverse control signal is in the second state, and the isolated feedback circuit is turned on, the detection signal output by the detection output port is in the first state, and the control unit determines that the AC motor is reversed; When the forward control signal output by the control unit is in the second state and the reverse control signal is in the first state, and the isolation feedback circuit is cut off, the detection signal output by the detection output port is in the second state, and the control unit determines that the AC motor is rotating forward; When the forward control signal output by the control unit is in the first state and the reverse control signal is in the second state and the isolation feedback circuit is cut off, the detection signal output by the detection output port is in the second state, and the control unit determines that the AC motor is stalled.

8. The washing machine control device according to claim 7, characterized in that: The isolated feedback circuit comprises a photoelectric coupler, a control end of the photoelectric coupler is connected to the AC motor, and a feedback output end of the isolated feedback circuit is connected to the detection output port.

9. The washing machine control device according to claim 8, characterized in that: The isolation feedback circuit also includes a first resistor, a second resistor, a third resistor, a first triode, a fourth resistor and a first filter capacitor; The collector of the phototransistor inside the photocoupler receives the power supply voltage, and is connected to the first end of the second resistor and the collector of the first transistor through the first resistor, the second end of the second resistor is connected to the detection output port, and is connected to the isolated ground terminal via the first filter capacitor; the emitter of the phototransistor inside the photocoupler is connected to the base of the first transistor through the third resistor, and the base of the first transistor is connected to the emitter of the first transistor through the fourth resistor and is connected to the isolated ground terminal.

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