A series motor control circuit and stirring device

Abstract

The present invention relates to a series motor control circuit and a stirring device, comprising: a DC power generation circuit, a switch circuit connected to the DC power generation circuit, a drive control circuit, a safety detection circuit respectively connected to the switch circuit and the drive control circuit, and a drive device respectively connected to the switch circuit; the DC power generation circuit is connected to an AC power source to rectify the received AC power and then output DC power; the safety detection circuit outputs a cut-off signal to the switch circuit and a status signal to the drive control circuit when a safety hazard occurs in the stirring device; the drive control circuit outputs a control signal to the switch circuit according to the status signal to control the switch circuit to brake the drive device according to the cut-off signal and the control signal. The present invention can realize the switching control of the operation and braking of the series motor in a low-cost and high-reliability manner, and has good safety performance.

Description

Technical Field

[0001] The present invention relates to the field of drive control, and more specifically, to a series motor control circuit and a stirring device. Background Art

[0002] Most of the existing kitchen mixing products use simple and inexpensive series motors. According to safety regulations, if the mixing cup becomes loose or moves away during mixing, the motor must reduce its speed to zero within a specified time (usually set to 2 seconds). Therefore, inertia alone cannot meet this requirement, which requires the motor to have a brake function.

[0003] For motors with braking functions, the common practice is to use relays to switch the operation and braking functions. However, if the power supply is a DC power supply, the conventional practice is to choose a high-voltage DC relay. However, high-voltage DC relays are very expensive, and their volume is many times larger than that of AC relays under the same specifications. Therefore, the existing method is costly and bulky, which is not conducive to its widespread application in mixing products. Summary of the invention

[0004] The technical problem to be solved by the present invention is to provide a series motor control circuit and a stirring device in view of the above-mentioned defects of the prior art.

[0005] The technical solution adopted by the present invention to solve the technical problem is: to provide a series motor control circuit, which is applied to a stirring device, comprising: a DC power supply generating circuit, a switch circuit connected to the DC power supply generating circuit, a drive control circuit, a safety detection circuit respectively connected to the switch circuit and the drive control circuit, and a drive device respectively connected to the switch circuit;

[0006] The DC power generation circuit is connected to the AC power source to rectify the received AC power and then output DC power;

[0007] When a potential safety hazard occurs in the stirring device, the safety detection circuit outputs a cut-off signal to the switch circuit and outputs a status signal to the drive control circuit;

[0008] The drive control circuit outputs a control signal to the switch circuit according to the state signal, so as to control the switch circuit to brake the drive device according to the cut-off signal and the control signal.

[0009] Preferably, the safety detection circuit comprises: a detection device, a second diode, a fourth capacitor and a twelfth resistor;

[0010] One end of the detection device is connected to a low-voltage DC power supply, and the other end is connected to the anode of the second diode, the cathode of the second diode is connected to the first end of the twelfth resistor, the second end of the twelfth resistor is grounded, and the fourth capacitor is connected in parallel with the twelfth resistor;

[0011] The connection end between the detection device and the anode of the second diode is connected to the switching circuit, and the connection end between the cathode of the second diode and the first end of the twelfth resistor is connected to the drive control circuit, so as to output the cut-off signal to the switching circuit and output the status signal to the drive control circuit respectively.

[0012] Preferably, the detection device comprises a micro switch or a Hall detector.

[0013] Preferably, the switch circuit includes a first switch circuit, a second switch circuit and a third switch circuit, and the control signal includes a first control signal, a second control signal and a third control signal;

[0014] The first switch circuit is connected between the AC power supply and the DC power supply generating circuit, and is respectively connected to the safety detection circuit and the drive control circuit;

[0015] The second switch circuit is connected between the DC power generation circuit and the drive device, and is respectively connected to the safety detection circuit and the drive control circuit;

[0016] The third switch circuit is connected between the safety detection circuit and the driving device, and is respectively connected to the output ends of the driving control circuit and the DC power generation circuit;

[0017] When the safety detection circuit outputs a cut-off signal and a status signal, the drive control circuit outputs a first control signal and a second control signal to the first switch circuit according to the status signal, and outputs a first control signal to the second switch circuit and a third control signal to the third switch circuit, so as to control the first switch circuit, the second switch circuit and the third switch circuit to cooperate with each other to brake the drive device.

[0018] Preferably, the first switch circuit includes a micro switch or a relay.

[0019] Preferably, it also includes: a zero-crossing detection circuit connected to the AC power supply and the drive control circuit respectively, for detecting whether the stirring device is abnormal.

[0020] Preferably, the zero-crossing detection circuit comprises: a twenty-seventh resistor, a twenty-ninth resistor, an eighth diode, a fifth optocoupler, a twenty-sixth resistor, a twenty-eighth resistor and an eighth capacitor;

[0021] The first end of the twenty-seventh resistor is connected to the first end of the AC power supply, the second end of the twenty-seventh resistor is connected to the first end of the fifth optocoupler, the cathode of the eighth diode is connected to the second end of the AC power supply, the anode of the eighth diode is connected to the first end of the twenty-ninth resistor, the second end of the twenty-ninth resistor is connected to the third end of the fifth optocoupler, the second end of the fifth optocoupler is connected to the second end of the twenty-sixth resistor and the first end of the twenty-eighth resistor, the fourth end of the fifth optocoupler is grounded, the first end of the twenty-sixth resistor is connected to the low-voltage DC power supply, the second end of the twenty-eighth resistor is connected to the drive control circuit, the first end of the eighth capacitor is connected to the second end of the twenty-eighth resistor, and the second end of the eighth capacitor is grounded.

[0022] Preferably, the first switch circuit includes: a first resistor, a photocoupler, a first transistor, a second resistor, a third resistor, a second transistor, a fourth resistor, a fifth resistor, an eighth resistor, a ninth resistor, a thyristor and a varistor;

[0023] The first end of the thyristor is connected to the first end of the AC power supply, the second end of the thyristor is connected to the second end of the ninth resistor and the first input end of the DC power supply generating circuit respectively, the varistor is connected in parallel to the first end and the second end of the thyristor, the third end of the thyristor is connected to the third end of the photocoupler through the eighth resistor, and the first end of the ninth resistor is connected to the fourth end of the photocoupler;

[0024] The first end of the photoelectric coupler is connected to the safety detection circuit through the first resistor, the second end of the photoelectric coupler is connected to the collector of the first transistor, the base of the first transistor is connected to the first control output end of the drive control circuit through the second resistor, the emitter of the first transistor is connected to the collector of the second transistor, the first end of the third resistor is connected to the base of the first transistor, and the second end of the third resistor is grounded;

[0025] The emitter of the second transistor is grounded, the base of the second transistor is connected to the second control output terminal of the drive control circuit through the fourth resistor, and the fifth resistor is connected between the base and the emitter of the second transistor.

[0026] Preferably, the second switch circuit includes a control switch, a connection circuit and a delay circuit;

[0027] The first end of the control switch is connected to a low-voltage DC power supply, and the second end of the control switch is connected to the first control output end of the drive control circuit through the connecting circuit; the first end of the delay circuit is connected to the safety detection circuit, and the second end of the delay circuit is connected to the connecting circuit.

[0028] Preferably, the control switch includes an AC relay, the connection circuit includes a third triode, a thirteenth resistor and a fourteenth resistor, and the delay circuit includes a fourth triode, a fifth triode, a fifteenth resistor, a sixteenth resistor, a capacitor EC3, a fourth diode and a seventeenth resistor;

[0029] The first end of the AC relay is connected to a low-voltage DC power supply, the second end of the AC relay is connected to the collector of the third transistor, the base of the third transistor is connected to the first control output end of the drive control circuit through the thirteenth resistor, the emitter of the third transistor is connected to the collector of the fifth transistor, the first end of the fourteenth resistor is connected to the base of the third transistor, and the second end of the fourteenth resistor is grounded;

[0030] The emitter of the fifth triode is grounded, the base of the fifth triode is connected to the emitter of the fourth triode, the collector of the fourth triode is respectively connected to the emitter of the third triode and the collector of the fifth triode, the base of the fourth triode is connected to the first end of the fifteenth resistor, the second end of the fifteenth resistor is connected to the cathode of the fourth diode, and the anode of the fourth diode is connected to the safety detection circuit;

[0031] The first end of the sixteenth resistor is connected to the base of the fourth transistor, the second end of the sixteenth resistor and the second end of the capacitor EC3 are grounded, and the first end of the capacitor EC3 is connected between the second end of the fifteenth resistor and the cathode of the fourth diode;

[0032] The third end of the AC relay is connected to the first end of the drive device, the fourth end of the AC relay is connected to the second end of the drive device, the fifth end of the AC relay is connected to the DC power supply generating circuit, the sixth end of the AC relay is connected to the third end of the drive device through the seventeenth resistor, the seventh end of the AC relay is connected to the third end of the drive device, and the eighth end of the AC relay is connected to the fourth end of the drive device.

[0033] Preferably, the third switch circuit includes: a sixth diode, a third inductor, a sixth capacitor, a twentieth resistor, a seventh diode, a seventh capacitor, a transistor, a voltage regulator, a twenty-second resistor, a twenty-fourth resistor, a fifth capacitor, an optical coupler driver, a sixth transistor, a twenty-first resistor, a nineteenth resistor, a seventh transistor, an eighteenth resistor, a twenty-third resistor, and a twenty-fifth resistor;

[0034] The cathode of the sixth diode, the first end of the third inductor and the first end of the sixth capacitor are commonly connected to the fifth end of the driving device, the anode of the sixth diode, the second end of the third inductor and the second end of the sixth capacitor are connected to the drain of the transistor, the anode of the seventh diode is connected to the drain of the transistor, the cathode of the seventh diode is grounded through the seventh capacitor, and the twentieth resistor is connected in parallel with the seventh diode;

[0035] The source of the transistor is grounded, the gate of the transistor is connected to the fifth terminal of the optocoupler driver through the twenty-second resistor, the gate of the transistor is also grounded through the twenty-fourth resistor, the voltage regulator is connected between the gate and the source of the transistor, the fourth terminal of the optocoupler driver is grounded, the sixth terminal of the optocoupler driver is connected to the output terminal of the DC power supply generating circuit, and the sixth terminal of the optocoupler driver is grounded through the fifth capacitor;

[0036] The first end of the optical coupling driver is connected to the low-voltage DC power supply and the first end of the eighteenth resistor, the third end of the optical coupling driver is connected to the emitter of the sixth transistor and the first end of the twenty-first resistor, the collector of the sixth transistor is connected to the low-voltage DC power supply and the first end of the optical coupling driver, the base of the sixth transistor is connected to the first end of the nineteenth resistor, the second end of the nineteenth resistor is connected to the third control output end of the drive control circuit, and the second end of the eighteenth resistor is connected to the second end of the nineteenth resistor;

[0037] The second end of the twenty-first resistor is connected to the collector of the seventh transistor, the emitter of the seventh transistor is grounded, the base of the seventh transistor is connected to the safety detection circuit through the twenty-third resistor, and the twenty-fifth resistor is connected between the base and emitter of the seventh transistor.

[0038] Preferably, the DC power generation circuit comprises: a rectifier output circuit and a power supply circuit;

[0039] The first input end of the rectifier output circuit is connected to the first switch circuit, the second input end of the rectifier output circuit is connected to the second end of the AC power supply, the first output end of the rectifier output circuit is connected to the second switch circuit and the first input end of the power supply circuit, the second output end of the rectifier output circuit is connected to the second input end of the power supply circuit, and the output end of the power supply circuit is connected to the third switch circuit.

[0040] Preferably, the driving device is a series motor.

[0041] The present invention also provides a stirring device, comprising the above-mentioned series-excited motor control circuit.

[0042] The implementation of the series-excited motor control circuit of the present invention has the following beneficial effects: the present invention detects potential safety hazards in the stirring device by using a safety detection circuit, and when a potential safety hazard occurs in the stirring device, immediately outputs a cut-off signal and a control signal to cut off the input of alternating current, and at the same time brakes the driving device to avoid danger. Moreover, the present invention has low cost, high reliability, and good safety performance, and can well implement switching control of the operation and braking of the series-excited motor. BRIEF DESCRIPTION OF THE DRAWINGS

[0043] The present invention will be further described below with reference to the accompanying drawings and embodiments, in which:

[0044] Figure 1 is a logic block diagram of a series-excited motor control circuit provided by an embodiment of the present invention;

[0045] Figure 2 is a schematic diagram of a part of a series motor control circuit provided by an embodiment of the present invention;

[0046] Figure 3 It is a schematic diagram of a safety detection circuit and a drive control circuit provided by an embodiment of the present invention. DETAILED DESCRIPTION

[0047] 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.

[0048] In order to solve the problem that when existing stirring products have safety hazards (such as the stirring cup is loose or moved away, etc.), the motor is required to reduce its speed to zero within a set time to avoid danger, the present invention provides a series-excited motor control circuit, which can realize switching control of the operation and braking of the motor in a low-cost, high-safety and high-reliability manner to ensure safe and reliable operation of the product.

[0049] refer to Figure 1 , is a logic block diagram of a series motor control circuit provided by an embodiment of the present invention. The series motor control circuit can be applied to mixing products, such as blenders, soybean milk machines, wall breaking machines, automatic cooking machines, etc.

[0050] like Figure 1As shown, the series-excited motor control circuit includes: a DC power supply generating circuit 30, a switching circuit connected to the DC power supply generating circuit 30, a drive control circuit 60, a safety detection circuit 70 respectively connected to the switching circuit and the drive control circuit 60, and a drive device 50 respectively connected to the switching circuit; the DC power supply generating circuit 30 is connected to an AC power supply 10 (AC Power) to rectify the received AC power and output DC power; the safety detection circuit 70 outputs a cut-off signal (P_SW) to the switch circuit and an output status signal (SW_SIGNAL) to the drive control circuit 60 when a safety hazard occurs in the stirring device; the drive control circuit 60 outputs a control signal to the switch circuit according to the status signal to control the switch 401 circuit to brake the drive device 50 according to the cut-off signal and the control signal.

[0051] Specifically, during the operation of the stirring device, the safety detection circuit 70 can detect whether there is a safety hazard in the stirring device. When a safety hazard occurs in the stirring device, the safety detection circuit 70 immediately outputs a cut-off signal to the switch circuit and an output status signal to the drive control circuit 60. After receiving the cut-off signal, the switch circuit cuts off the input of the AC power supply 10. The drive control circuit 60 also outputs a corresponding control signal to the switch circuit according to the received status signal, so that the switch circuit can realize braking control of the drive device 50 according to the cut-off signal and the control signal, even if the drive device 50 has a braking function. Therefore, when a safety hazard occurs, the drive device 50 can quickly reduce the speed to zero while the power is cut off, thereby ensuring the safe use of the stirring device, avoiding danger, and improving the safety and reliability of the stirring device.

[0052] Furthermore, the safety detection circuit 70 of the embodiment of the present invention may include a detection device and a related detection circuit, wherein the detection device may include a micro switch or a Hall detector. For example, when a potential safety hazard is detected in the stirring device, the micro switch is immediately disconnected, and the disconnection signal (i.e., the aforementioned cut-off signal) is transmitted to the switch circuit, and a corresponding state signal is output to the drive control circuit 60 at the same time.

[0053] Furthermore, if Figure 1 As shown, the switch circuit of the embodiment of the present invention may include: a first switch circuit 20, a second switch circuit 40 and a third switch circuit 80. The control signal includes a first control signal (RLY_CTRL), a second control signal (SR_CTRL) and a third control signal (MOTOR_CTRL).

[0054] Specifically, the first switch circuit 20 is connected between the AC power supply 10 and the DC power supply generating circuit 30, and is respectively connected to the safety detection circuit 70 and the drive control circuit 60; the second switch circuit 40 is connected between the DC power supply generating circuit 30 and the drive device 50, and is respectively connected to the safety detection circuit 70 and the drive control circuit 60; the third switch circuit 80 is connected between the safety detection circuit 70 and the drive device 50, and is respectively connected to the output ends of the drive control circuit 60 and the DC power supply generating circuit 30; when the safety detection circuit 70 outputs a cut-off signal and a status signal, the drive control circuit 60 outputs a first control signal and a second control signal to the first switch circuit 20 according to the status signal, and outputs a first control signal to the second switch circuit 40 and outputs a third control signal to the third switch circuit 80, so as to control the first switch circuit 20, the second switch circuit 40 and the third switch circuit 80 to cooperate with each other to brake the drive device 50.

[0055] In the embodiment of the present invention, the first switch circuit 20 is used to close or disconnect the AC power supply 10. Specifically, when the stirring device is working normally, the first switch circuit 20 closes the AC power supply 10 to ensure the normal power supply of the stirring device; when the stirring device has a safety hazard (such as the stirring cup is loose or moved away), the first switch circuit 20 disconnects the AC power supply 10 to cut off the power supply of the stirring device. Optionally, the first switch circuit 20 in the embodiment of the present invention can use a micro switch or a relay to realize the input control of the AC power supply 10, or can use a related switch switching circuit to realize it.

[0056] In the embodiment of the present invention, the DC power generation circuit 30 is used to generate DC power by rectifying the connected AC power 10, and the DC power is high voltage DC power.

[0057] In the embodiment of the present invention, the second switch circuit 40 is used to switch the operation and braking of the driving device 50, so as to cooperate with the first switch circuit 20 and the third switch circuit 80 to realize braking control of the driving device 50 and avoid danger when a safety hazard occurs in the stirring device.

[0058] The third switch circuit 80 is used to control the on and off of the driving device 50 , and can also control its rotation speed, and cooperate with the first switch circuit 20 and the second switch circuit 40 to achieve braking control of the driving device 50 .

[0059] The driving control circuit 60 includes a control chip U2, wherein I / O-1 of the control chip U2 serves as the first input terminal of the driving control circuit 60 and is used to receive status information, and I / O-2 of the control chip U2 serves as the second input terminal of the driving control circuit 60 and receives a zero-crossing detection signal; I / O-3 of the control chip U2 serves as the first control output terminal of the driving control circuit 60 and outputs a first control signal, I / O-4 of the control chip U2 serves as the second control output terminal of the driving control circuit 60 and outputs a second control signal, and I / O-5 of the control chip U2 serves as the third control output terminal of the driving control circuit 60 and outputs a third control signal.

[0060] The control chip U2 is used to output the first control signal to the first switch circuit 20 and the second switch circuit 40 according to the received state signal when a potential safety hazard occurs in the stirring device, and output the second control signal to the first switch circuit 20 and the third control signal to the third switch circuit 80, so as to control the first switch circuit 20, the second switch circuit 40 and the third switch circuit 80 to cooperate in the brake function, realize the brake control of the drive device 50, and enable the drive device 50 to stop quickly. Among them, when a potential safety hazard occurs, the first switch circuit 20 and the third switch circuit 80 are disconnected first, and then the second switch circuit 40 is disconnected after a delay, thereby ensuring that the control switch 401 in the second switch circuit 40 will not be damaged.

[0061] Figure 2 and Figure 3 A preferred embodiment of the series-excited motor control circuit provided by the present invention is shown.

[0062] like Figure 3 As shown, the safety detection circuit 70 includes: a detection device, a second diode D2, a fourth capacitor C4 and a twelfth resistor R12.

[0063] One end of the detection device is connected to a low voltage DC power supply (VDD), and the other end is connected to the anode of the second diode D2, the cathode of the second diode D2 is connected to the first end of the twelfth resistor R12, the second end of the twelfth resistor R12 is grounded, and the fourth capacitor C4 is connected in parallel with the twelfth resistor R12; the connection end of the detection device and the anode of the second diode D2 is connected to the switch circuit, and the connection end of the cathode of the second diode D2 and the first end of the twelfth resistor R12 is connected to the drive control circuit 60, so as to output a cut-off signal to the switch circuit and an output state signal to the drive control circuit 60 respectively. Optionally, the detection device may include a micro switch or a Hall detector. Among them, the anode of the second diode D2 is the first output end of the safety detection circuit 70, and the connection end of the cathode of the second diode D2 and the first end of the twelfth resistor R12 is the second output end of the safety detection circuit 70.

[0064] like Figure 2As shown, the first switch circuit 20 includes: a first resistor R1, a photocoupler U1, a first transistor Q1, a second resistor R2, a third resistor R3, a second transistor Q2, a fourth resistor R4, a fifth resistor R5, an eighth resistor R8, a ninth resistor R9, a thyristor SR1 and a varistor ZR1.

[0065] The first end of the thyristor SR1 is connected to the first end of the AC power supply 10, the second end of the thyristor SR1 is respectively connected to the second end of the ninth resistor R9 and the first input end of the DC power supply generating circuit 30, the varistor ZR1 is connected in parallel to the first end and the second end of the thyristor SR1, the third end of the thyristor SR1 is connected to the third end of the photocoupler U1 through the eighth resistor R8, and the first end of the ninth resistor R9 is connected to the fourth end of the photocoupler U1; the first end of the photocoupler U1 is connected to the safety detection circuit 70 (specifically connected to the anode of the second diode D2, such as Figure 3 As shown), the second end of the photocoupler U1 is connected to the collector of the first transistor Q1, the base of the first transistor Q1 is connected to the first control output end of the drive control circuit 60 through the second resistor R2, the emitter of the first transistor Q1 is connected to the collector of the second transistor Q2, the first end of the third resistor R3 is connected to the base of the first transistor Q1, and the second end of the third resistor R3 is grounded; the emitter of the second transistor Q2 is grounded, the base of the second transistor Q2 is connected to the second control output end of the drive control circuit 60 through the fourth resistor R4, and the fifth resistor R5 is connected between the base and the emitter of the second transistor Q2.

[0066] like Figure 2 As shown, the second switch circuit 40 includes a control switch 401, a connecting circuit and a delay circuit.

[0067] The first end of the control switch 401 is connected to a low-voltage DC power supply, and the second end of the control switch 401 is connected to the first control output end of the drive control circuit 60 through a connecting circuit; the first end of the delay circuit is connected to the safety detection circuit 70, and the second end of the delay circuit is connected to the connecting circuit.

[0068] In this embodiment, the control switch 401 includes an AC relay, the connection circuit includes a third transistor Q3, a thirteenth resistor R13 and a fourteenth resistor R14, and the delay circuit includes a fourth transistor Q4, a fifth transistor Q5, a fifteenth resistor R15, a sixteenth resistor R16, a capacitor EC3, a fourth diode D4 and a seventeenth resistor R17.

[0069] A first end of the AC relay is connected to a low-voltage DC power supply, a second end of the AC relay is connected to the collector of the third triode Q3, a base of the third triode Q3 is connected to the first control output end of the drive control circuit 60 through a thirteenth resistor R13, an emitter of the third triode Q3 is connected to the collector of the fifth triode Q5, a first end of the fourteenth resistor R14 is connected to the base of the third triode Q3, and a second end of the fourteenth resistor R14 is grounded; an emitter of the fifth triode Q5 is grounded, a base of the fifth triode Q5 is connected to the emitter of the fourth triode Q4, a collector of the fourth triode Q4 is respectively connected to the emitter of the third triode Q3 and the collector of the fifth triode Q5, a base of the fourth triode Q4 is connected to a first end of a fifteenth resistor R15, a second end of the fifteenth resistor R15 is connected to the cathode of the fourth diode D4, and an anode of the fourth diode D4 is connected to a safety detection circuit 70 (specifically connected to the anode of the second diode D2, as Figure 3 The first end of the sixteenth resistor R16 is connected to the base of the fourth transistor Q4, the second end of the sixteenth resistor R16 and the second end of the capacitor EC3 are grounded, and the first end of the capacitor EC3 is connected between the second end of the fifteenth resistor R15 and the cathode of the fourth diode D4.

[0070] The third end of the AC relay is connected to the first end of the driving device 50, the fourth end of the AC relay is connected to the second end of the driving device 50, the fifth end of the AC relay is connected to the DC power supply generating circuit 30, the sixth end of the AC relay is connected to the third end of the driving device 50 through the seventeenth resistor R17, the seventh end of the AC relay is connected to the third end of the driving device 50, and the eighth end of the AC relay is connected to the fourth end of the driving device 50.

[0071] In the embodiment of the present invention, the delay circuit can ensure that the AC relay works at a normal voltage, and the seventeenth resistor R17 can limit the current flowing through the drive device 50 (ie, the motor) when the drive device 50 is in a braking state (brake state). Preferably, the drive device 50 in the embodiment of the present invention is a series-excited motor.

[0072] like Figure 2 As shown, the third switch circuit 80 includes: a sixth diode D6, a third inductor L3, a sixth capacitor C6, a twentieth resistor R20, a seventh diode D7, a seventh capacitor C7, a transistor, a voltage regulator ZD1, a twenty-second resistor R22, a twenty-fourth resistor R24, a fifth capacitor C5, an optocoupler driver U4, a sixth transistor Q6, a twenty-first resistor R21, a nineteenth resistor R19, a seventh transistor Q7, an eighteenth resistor R18, a twenty-third resistor R23 and a twenty-fifth resistor R25.

[0073] The cathode of the sixth diode D6, the first end of the third inductor L3 and the first end of the sixth capacitor C6 are commonly connected to the fifth end of the driving device 50, the anode of the sixth diode D6, the second end of the third inductor L3 and the second end of the sixth capacitor C6 are connected to the drain of the transistor, the anode of the seventh diode D7 is connected to the drain of the transistor, the cathode of the seventh diode D7 is grounded through the seventh capacitor C7, and the twentieth resistor R20 is connected in parallel with the seventh diode D7; the source of the transistor is grounded, the gate of the transistor is connected to the fifth end of the optocoupler driver U4 through the twenty-second resistor R22, the gate of the transistor is also grounded through the twenty-fourth resistor R24, the voltage regulator ZD1 is connected between the gate and the source of the transistor, the fourth end of the optocoupler driver U4 is grounded, the sixth end of the optocoupler driver U4 is connected to the output end of the DC power supply generating circuit 30, and the sixth end of the optocoupler driver U4 is grounded through the fifth capacitor C5.

[0074] The first end of the optocoupler driver U4 is connected to the low-voltage DC power supply and the first end of the eighteenth resistor R18, the third end of the optocoupler driver U4 is connected to the emitter of the sixth transistor Q6 and the first end of the twenty-first resistor R21, the collector of the sixth transistor Q6 is connected to the low-voltage DC power supply and the first end of the optocoupler driver U4, the base of the sixth transistor Q6 is connected to the first end of the nineteenth resistor R19, the second end of the nineteenth resistor R19 is connected to the third control output end of the drive control circuit 60, the second end of the eighteenth resistor R18 is connected to the second end of the nineteenth resistor R19; the second end of the twenty-first resistor R21 is connected to the collector of the seventh transistor Q7, the emitter of the seventh transistor Q7 is grounded, and the base of the seventh transistor Q7 is connected to the safety detection circuit 70 (specifically connected to the anode of the second diode D2 (i.e., the first output end of the safety detection circuit 70) through the twenty-third resistor R23, as shown Figure 3 As shown), the twenty-fifth resistor R25 is connected between the base and the emitter of the seventh transistor Q7.

[0075] In the embodiment of the present invention, the transistor is an insulated dual-gate transistor (IGBT).

[0076] like Figure 2 As shown, the DC power generation circuit 30 includes: a rectifier output circuit and a power supply circuit.

[0077] The first input end of the rectifier output circuit is connected to the first switch circuit 20, the second input end of the rectifier output circuit is connected to the second end of the AC power supply 10, the first output end of the rectifier output circuit is connected to the second switch circuit 40 and the first input end of the power supply circuit, the second output end of the rectifier output circuit is connected to the second input end of the power supply circuit, and the output end of the power supply circuit is connected to the third switch circuit 80.

[0078] like Figure 2As shown, the rectifier output circuit includes a rectifier bridge BD1, a resistor RT1, a capacitor EC1, a third capacitor C3, a tenth resistor R10 and an eleventh resistor R11. The power supply circuit includes a power supply chip U3, a first capacitor C1, a sixth resistor R6, a seventh resistor R7, a second capacitor C2, a first diode D1, a second inductor L2, a capacitor EC2 and a diode PD1.

[0079] The first input end of the rectifier bridge BD1 is connected to the second end of the varistor ZR1 and the second end of the thyristor SR1 as the first input end of the rectifier output circuit, and the second input end of the rectifier bridge BD1 is connected to the second end of the AC power supply 10 as the second input end of the rectifier output circuit; the first output end of the rectifier bridge BD1 is connected to the fifth end of the AC relay and the first input end of the power supply circuit (i.e., the 4th pin of the power supply chip U3) through the resistor RT1 as the first output end of the rectifier output circuit, and the second output end of the rectifier bridge BD1 is connected to the anode of the diode PD1 as the second output end of the rectifier output circuit; the first end of the tenth resistor R10 is connected to the second end of the resistor RT1, the second end of the tenth resistor R10 is connected to the first end of the eleventh resistor R11, and the second end of the eleventh resistor R11 is grounded; the third capacitor C3 and the capacitor EC1 are connected in parallel to the first end of the tenth resistor R10 and the second end of the eleventh resistor R11 respectively.

[0080] The first pin of the power chip U3 is connected to its eighth pin through the first capacitor C1, the second pin of the power chip is connected to the first end of the sixth resistor R6, the second end of the sixth resistor R6 is connected to the eighth pin of the power chip U3, the first end of the sixth resistor R6 is also connected to the fifth pin of the power chip U3 through the seventh resistor R7 and the second capacitor C2 in sequence, the cathode of the diode PD1 is connected to the fifth pin of the power chip U3, the fifth pin, the sixth pin, the seventh pin and the eighth pin of the power chip U3 are short-circuited, the fifth pin of the power chip U3 is also connected to the ground through the second inductor L2 and the capacitor EC2 in sequence, the cathode of the first diode D1 is connected to the connection end of the seventh resistor R7 and the second capacitor C2, the anode of the first diode D1 is connected to the connection end of the second inductor L2 and the capacitor EC2, wherein the connection end of the second inductor L2 and the capacitor EC2 is connected to the sixth end of the optocoupler driver U4 as the output end of the power circuit, for outputting high-voltage direct current (VCC to the third switching circuit 80).

[0081] Furthermore, in another embodiment, when the first switch circuit is implemented by a micro switch or a relay, the series motor control circuit further includes: a zero-crossing detection circuit 90. The zero-crossing detection circuit 90 is connected to the AC power supply 10 and the drive control circuit 60 respectively, and is used to detect whether the stirring device is abnormal, and output a zero-crossing detection signal to the drive control circuit 60 when the stirring device is abnormal.

[0082] In a preferred embodiment, Figure 2 As shown, the zero-crossing detection circuit 90 includes: a twenty-seventh resistor R27, a twenty-ninth resistor R29, an eighth diode D8, a fifth optical coupler U5, a twenty-sixth resistor R26, a twenty-eighth resistor R28 and an eighth capacitor C8;

[0083] A first end of the twenty-seventh resistor R27 is connected to a first end of the AC power supply, a second end of the twenty-seventh resistor R27 is connected to a first end of the fifth optocoupler U5, a cathode of the eighth diode D8 is connected to the second end of the AC power supply, an anode of the eighth diode D8 is connected to a first end of the twenty-ninth resistor R29, a second end of the twenty-ninth resistor R29 is connected to a third end of the fifth optocoupler U5, a second end of the fifth optocoupler U5 is connected to a second end of the twenty-sixth resistor R26 and a first end of the twenty-eighth resistor R28, a fourth end of the fifth optocoupler U5 is grounded, a first end of the twenty-sixth resistor R26 is connected to a low-voltage DC power supply VDD, a second end of the twenty-eighth resistor R28 is connected to a second input end of the drive control circuit 60, a first end of the eighth capacitor C8 is connected to a second end of the twenty-eighth resistor R28, and a second end of the eighth capacitor C8 is grounded.

[0084] The present invention also provides a stirring device, which may include the series motor control circuit provided in the embodiment of the present invention. The stirring device includes but is not limited to stirring products such as a blender, a soybean milk machine, a wall breaking machine, and an automatic cooking machine.

[0085] The above embodiments are only for illustrating the technical concept and features of the present invention, and their purpose is to enable people familiar with the technology to understand the content of the present invention and implement it accordingly, and they cannot limit the scope of protection of the present invention. All equivalent changes and modifications made to the scope of the claims of the present invention should fall within the scope of the claims of the present invention.

[0086] It should be understood that those skilled in the art can make improvements or changes based on the above description, and all these improvements and changes should fall within the scope of protection of the appended claims of the present invention.

Claims

1. A series motor control circuit, applied to a stirring device, characterized in that: include: A DC power generation circuit, a switch circuit connected to the DC power generation circuit, a drive control circuit, a safety detection circuit connected to the switch circuit and the drive control circuit respectively, and a drive device connected to the switch circuit; The DC power generation circuit is connected to the AC power source to rectify the received AC power and then output DC power; When a potential safety hazard occurs in the stirring device, the safety detection circuit outputs a cut-off signal to the switch circuit and outputs a status signal to the drive control circuit; The drive control circuit outputs a control signal to the switch circuit according to the state signal, so as to control the switch circuit to brake the drive device according to the cut-off signal and the control signal; The switch circuit includes a first switch circuit, a second switch circuit and a third switch circuit, and the control signal includes a first control signal, a second control signal and a third control signal; The first switch circuit is connected between the AC power supply and the DC power supply generating circuit, and is connected to the safety detection circuit and the drive control circuit respectively; the second switch circuit is connected between the DC power supply generating circuit and the drive device, and is connected to the safety detection circuit and the drive control circuit respectively; the third switch circuit is connected between the safety detection circuit and the drive device, and is connected to the output end of the drive control circuit and the DC power supply generating circuit respectively; When the safety detection circuit outputs a cut-off signal and a status signal, the drive control circuit outputs a first control signal and a second control signal to the first switch circuit according to the status signal, and outputs a first control signal to the second switch circuit and a third control signal to the third switch circuit, so as to control the first switch circuit, the second switch circuit and the third switch circuit to cooperate with each other to brake the drive device.

2. The series motor control circuit according to claim 1, characterized in that: The safety detection circuit comprises: a detection device, a second diode, a fourth capacitor and a twelfth resistor; One end of the detection device is connected to a low-voltage DC power supply, and the other end is connected to the anode of the second diode, the cathode of the second diode is connected to the first end of the twelfth resistor, the second end of the twelfth resistor is grounded, and the fourth capacitor is connected in parallel with the twelfth resistor; The connection end between the detection device and the anode of the second diode is connected to the switching circuit, and the connection end between the cathode of the second diode and the first end of the twelfth resistor is connected to the drive control circuit, so as to output the cut-off signal to the switching circuit and output the status signal to the drive control circuit respectively.

3. The series motor control circuit according to claim 1, characterized in that: The detection device includes a micro switch or a Hall detector.

4. The series motor control circuit according to claim 1, characterized in that: The first switch circuit includes a micro switch or a relay.

5. The series motor control circuit according to claim 1, characterized in that: Also includes: A zero-crossing detection circuit is respectively connected to the AC power supply and the drive control circuit to detect whether the stirring device is abnormal.

6. The series motor control circuit according to claim 5, characterized in that: The zero-crossing detection circuit includes: a twenty-seventh resistor, a twenty-ninth resistor, an eighth diode, a fifth optical coupler, a twenty-sixth resistor, a twenty-eighth resistor and an eighth capacitor; The first end of the twenty-seventh resistor is connected to the first end of the AC power supply, the second end of the twenty-seventh resistor is connected to the first end of the fifth optocoupler, the cathode of the eighth diode is connected to the second end of the AC power supply, the anode of the eighth diode is connected to the first end of the twenty-ninth resistor, the second end of the twenty-ninth resistor is connected to the third end of the fifth optocoupler, the second end of the fifth optocoupler is connected to the second end of the twenty-sixth resistor and the first end of the twenty-eighth resistor, the fourth end of the fifth optocoupler is grounded, the first end of the twenty-sixth resistor is connected to the low-voltage DC power supply, the second end of the twenty-eighth resistor is connected to the drive control circuit, the first end of the eighth capacitor is connected to the second end of the twenty-eighth resistor, and the second end of the eighth capacitor is grounded.

7. The series motor control circuit according to claim 1, characterized in that: The first switch circuit includes: a first resistor, a photocoupler, a first transistor, a second resistor, a third resistor, a second transistor, a fourth resistor, a fifth resistor, an eighth resistor, a ninth resistor, a thyristor and a varistor; The first end of the thyristor is connected to the first end of the AC power supply, the second end of the thyristor is connected to the second end of the ninth resistor and the first input end of the DC power supply generating circuit respectively, the varistor is connected in parallel to the first end and the second end of the thyristor, the third end of the thyristor is connected to the third end of the photocoupler through the eighth resistor, and the first end of the ninth resistor is connected to the fourth end of the photocoupler; The first end of the photoelectric coupler is connected to the safety detection circuit through the first resistor, the second end of the photoelectric coupler is connected to the collector of the first transistor, the base of the first transistor is connected to the first control output end of the drive control circuit through the second resistor, the emitter of the first transistor is connected to the collector of the second transistor, the first end of the third resistor is connected to the base of the first transistor, and the second end of the third resistor is grounded; The emitter of the second transistor is grounded, the base of the second transistor is connected to the second control output terminal of the drive control circuit through the fourth resistor, and the fifth resistor is connected between the base and the emitter of the second transistor.

8. The series motor control circuit according to claim 1, characterized in that: The second switch circuit includes a control switch, a connection circuit and a delay circuit; The first end of the control switch is connected to a low-voltage DC power supply, and the second end of the control switch is connected to the first control output end of the drive control circuit through the connecting circuit; the first end of the delay circuit is connected to the safety detection circuit, and the second end of the delay circuit is connected to the connecting circuit.

9. The series motor control circuit according to claim 8, characterized in that: The control switch includes an AC relay, the connection circuit includes a third triode, a thirteenth resistor and a fourteenth resistor, and the delay circuit includes a fourth triode, a fifth triode, a fifteenth resistor, a sixteenth resistor, a capacitor EC3, a fourth diode and a seventeenth resistor; The first end of the AC relay is connected to a low-voltage DC power supply, the second end of the AC relay is connected to the collector of the third transistor, the base of the third transistor is connected to the first control output end of the drive control circuit through the thirteenth resistor, the emitter of the third transistor is connected to the collector of the fifth transistor, the first end of the fourteenth resistor is connected to the base of the third transistor, and the second end of the fourteenth resistor is grounded; The emitter of the fifth triode is grounded, the base of the fifth triode is connected to the emitter of the fourth triode, the collector of the fourth triode is respectively connected to the emitter of the third triode and the collector of the fifth triode, the base of the fourth triode is connected to the first end of the fifteenth resistor, the second end of the fifteenth resistor is connected to the cathode of the fourth diode, and the anode of the fourth diode is connected to the safety detection circuit; The first end of the sixteenth resistor is connected to the base of the fourth transistor, the second end of the sixteenth resistor and the second end of the capacitor EC3 are grounded, and the first end of the capacitor EC3 is connected between the second end of the fifteenth resistor and the cathode of the fourth diode; The third end of the AC relay is connected to the first end of the drive device, the fourth end of the AC relay is connected to the second end of the drive device, the fifth end of the AC relay is connected to the DC power supply generating circuit, the sixth end of the AC relay is connected to the third end of the drive device through the seventeenth resistor, the seventh end of the AC relay is connected to the third end of the drive device, and the eighth end of the AC relay is connected to the fourth end of the drive device.

10. The series motor control circuit according to claim 1, characterized in that: The third switch circuit includes: a sixth diode, a third inductor, a sixth capacitor, a twentieth resistor, a seventh diode, a seventh capacitor, a transistor, a voltage regulator, a twenty-second resistor, a twenty-fourth resistor, a fifth capacitor, an optical coupler driver, a sixth transistor, a twenty-first resistor, a nineteenth resistor, a seventh transistor, an eighteenth resistor, a twenty-third resistor and a twenty-fifth resistor; The cathode of the sixth diode, the first end of the third inductor and the first end of the sixth capacitor are commonly connected to the fifth end of the driving device, the anode of the sixth diode, the second end of the third inductor and the second end of the sixth capacitor are connected to the drain of the transistor, the anode of the seventh diode is connected to the drain of the transistor, the cathode of the seventh diode is grounded through the seventh capacitor, and the twentieth resistor is connected in parallel with the seventh diode; The source of the transistor is grounded, the gate of the transistor is connected to the fifth terminal of the optocoupler driver through the twenty-second resistor, the gate of the transistor is also grounded through the twenty-fourth resistor, the voltage regulator is connected between the gate and the source of the transistor, the fourth terminal of the optocoupler driver is grounded, the sixth terminal of the optocoupler driver is connected to the output terminal of the DC power supply generating circuit, and the sixth terminal of the optocoupler driver is grounded through the fifth capacitor; The first end of the optical coupling driver is connected to the low-voltage DC power supply and the first end of the eighteenth resistor, the third end of the optical coupling driver is connected to the emitter of the sixth transistor and the first end of the twenty-first resistor, the collector of the sixth transistor is connected to the low-voltage DC power supply and the first end of the optical coupling driver, the base of the sixth transistor is connected to the first end of the nineteenth resistor, the second end of the nineteenth resistor is connected to the third control output end of the drive control circuit, and the second end of the eighteenth resistor is connected to the second end of the nineteenth resistor; The second end of the twenty-first resistor is connected to the collector of the seventh transistor, the emitter of the seventh transistor is grounded, the base of the seventh transistor is connected to the safety detection circuit through the twenty-third resistor, and the twenty-fifth resistor is connected between the base and emitter of the seventh transistor.

11. The series motor control circuit according to claim 1, characterized in that: The DC power generation circuit comprises: a rectifier output circuit and a power supply circuit; The first input end of the rectifier output circuit is connected to the first switch circuit, the second input end of the rectifier output circuit is connected to the second end of the AC power supply, the first output end of the rectifier output circuit is connected to the second switch circuit and the first input end of the power supply circuit, the second output end of the rectifier output circuit is connected to the second input end of the power supply circuit, and the output end of the power supply circuit is connected to the third switch circuit.

12. The series motor control circuit according to claim 1, characterized in that: The driving device is a series motor.

13. A stirring device, characterized in that: A series-excited motor control circuit comprising the control circuit of any one of claims 1-12.

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