Brushless direct current motor circuit for tea-leaf picker

Abstract

The utility model discloses a brushless direct-current motor circuit for a tea-leaf picker, and the circuit comprises a power unit which outputs a plurality of direct-current voltages to respectively provide electric energy for a control chip, a drive chip, and a drive circuit; the power supply unit comprises a first PNP-type triode and a second NPN-type triode, the first PNP-type triode is conducted to output direct-current voltage, and the second NPN-type triode is connected with a base electrode of the first PNP-type triode to receive signals to control the first PNP-type triode to be cut off; the driving circuit comprises a three-phase inverter bridge formed by six MOS (Metal Oxide Semiconductor) tubes, and is used for inverting direct current into alternating current and outputting the alternating current to the brushless direct current motor; the driving chip is connected with the driving circuit to output a signal to control the on-off of the MOS tube; and the control chip outputs a control signal to the driving chip, so that the driving chip outputs a specific signal to repeatedly switch on and switch off the MOS tube. And the power supply unit is controlled by the triode to realize real-time instantaneous starting or stopping of the motor.

Description

TECHNICAL FIELD

[0001] The utility model relates to motor circuit technical field, especially a kind of brushless DC motor circuit for tea picker. BACKGROUND

[0002] Tea picker is a kind of crop harvesting machinery for picking new tender tea leaves from the top of tea tree;Now, tea picker generally uses motor drive.

[0003] Due to the production design requirement of tea picker, a brushless DC motor circuit needs to be designed, which can start or stop the rotation of motor at any time, and complete the start or stop operation quickly in an instant. SUMMARY

[0004] The utility model aims at providing a kind of brushless DC motor circuit for tea picker, adopt first PNP triode and second NPN triode and form switch tube structure control power supply unit to the conversion of power supply, to control the rotation or stop of DC motor in real time.

[0005] The above technical purpose of the utility model is realized by the following technical scheme: a kind of brushless DC motor circuit for tea picker, comprising: power supply unit, the power supply unit exports several direct current voltages and provides electric energy for control chip, drive chip and drive circuit respectively;The power supply unit includes first PNP triode and second NPN triode, the first PNP triode conduction output direct current voltage, the second NPN triode is connected the base of the first PNP triode and receives signal control the first PNP triode cut-off;Drive circuit, the drive circuit includes the three-phase inverter bridge of six MOS tubes, and direct current is converted into alternating current and is exported to brushless DC motor;Drive chip, the drive chip is connected the output signal of the drive circuit and controls the on-off of MOS tube;Control chip, the control chip exports control signal to the drive chip and makes the drive chip output specific signal repeatedly on-off MOS tube.

[0006] By adopting the above technical scheme, the first PNP triode and the second NPN triode are used to form switch tube structure to control the start or stop of power supply unit, and the control chip can output control signal to stop the circuit in real time.

[0007] The utility model further provides: the emitter of the first PNP triode is connected with direct current power supply Vbat, the collector of the first PNP triode exports direct current voltage, resistance R46 is connected between the emitter and the base of the first PNP triode, resistance R53 is connected between the base of the first PNP triode and the collector of the second NPN triode, and the emitter of the second NPN triode is connected with ground point.

[0008] The utility model discloses further provide: power unit still include third NPN triode and voltage reducing chip, the collector of third NPN triode connects the collector of first PNP triode, the emitter of third NPN triode connects voltage reducing chip.

[0009] The utility model discloses further provide: the first PNP triode output direct current voltage is Vbus, the third NPN triode output direct current voltage is VDrive, voltage reducing chip exports 5V direct current voltage.

[0010] The utility model discloses further provide: the emitter of third NPN triode connects the positive pole of stabilivolt diode DZ2, the negative pole of stabilivolt diode DZ2 connects the grounding point, and the collector and the base of third NPN triode are connected with resistance R59.

[0011] The utility model discloses further provide: the collector of second NPN triode connects resistance R55, and resistance R55 connects the positive pole of diode D5, D9 respectively, and the negative pole of diode D5, D9 connects the port respectively, and diode D5 negative pole connects diode D6 negative pole, and diode D6 positive pole connects resistance R85 and then connects control chip again, and diode D9 negative pole connects diode D10 negative pole, and diode D10 positive pole connects resistance R65 and then connects control chip again.

[0012] The utility model discloses further provide: drive chip is connected with bootstrap circuit.

[0013] The utility model discloses further provide: the MOS pipe gate of drive circuit is connected with drive chip respectively, and the MOS pipe gate and source are connected with resistance respectively.

[0014] The utility model discloses further provide: still include acquisition circuit, and acquisition circuit is connected with three-phase inverter bridge through sampling resistance CR1.

[0015] The utility model discloses further provide: acquisition circuit includes acquisition chip U5 and its accessory circuit, and acquisition circuit is connected with control chip signal.

[0016] Compared with the prior art, the utility model has the advantages that: a brushless DC motor circuit for tea picking machine adopts first PNP triode and second NPN triode to form a switching tube structure to control the conversion of the power unit, thereby controlling the rotation or stop of the DC motor in real time, and completing the start or stop operation instantaneously and quickly. BRIEF DESCRIPTION OF DRAWINGS

[0017] Figure 1 It is the principle block diagram of the brushless DC motor circuit for tea picking machine in the embodiment.

[0018] Figure 2 is the circuit diagram of the control chip in the embodiment.

[0019] Figure 3 is the circuit diagram of the power supply unit in the embodiment.

[0020] Figure 4 is the circuit diagram of the driving chip in the embodiment.

[0021] Figure 5 is the circuit diagram of the driving circuit and the collection circuit in the embodiment.

[0022] In the figure: 1, control chip; 2, power supply unit; 3, driving chip; 4, driving circuit; 5, collection circuit. DETAILED DESCRIPTION

[0023] The technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the drawings in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, rather than all the embodiments of the present application. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative labor fall within the scope of protection of the present application. It should be noted that the terms "upper", "lower", "inner", "outer", "top / bottom end" and the like indicate the orientation or positional relationship shown in the drawings, and are only used for the purpose of facilitating the description of the present application and simplifying the description, and do not indicate or imply that the devices or elements referred to must have a particular orientation, be constructed and operated in a particular orientation, and therefore cannot be understood as a limitation on the present application. In addition, the terms "first" and "second" are only used for descriptive purposes and cannot be understood as indicating or implying relative importance.

[0024] A brushless DC motor circuit for a tea picking machine is disclosed in the embodiment, which is used to drive the brushless DC motor in the tea picking machine to drive the motor to operate and drive the tea picking machine to work. Figure 1 As shown in the figure, the brushless DC motor circuit for the tea picking machine comprises a control chip 1, a power supply unit 2, a driving chip 3 and a driving circuit 4. The control chip 1 is connected to the power supply unit 2 to control the output of the DC power supply of the power supply unit 2. The power supply unit 2 outputs various DC power supplies to provide power for the control chip 1, the driving chip 3 and the driving circuit 4. The driving chip 3 is connected to the control chip 1 and the driving circuit 4, respectively, and outputs signals to turn on the driving circuit 4 to make the current output in a forward or reverse direction to drive the motor to operate.

[0025] As shown in the figure, the brushless DC motor circuit for the tea picking machine comprises a control chip 1, a power supply unit 2, a driving chip 3 and a driving circuit 4. The control chip 1 is connected to the power supply unit 2 to control the output of the DC power supply of the power supply unit 2. The power supply unit 2 outputs various DC power supplies to provide power for the control chip 1, the driving chip 3 and the driving circuit 4. The driving chip 3 is connected to the control chip 1 and the driving circuit 4, respectively, and outputs signals to turn on the driving circuit 4 to make the current output in a forward or reverse direction to drive the motor to operate. Figure 2As shown, the control chip 1 in the embodiment is chip U4, which is a 32-pin single-chip microcomputer, powered by 5V DC voltage, and each pin of the chip U4 is connected to each module for input signal and output control signal, wherein the pin 14, pin 15, pin 16, pin 17, pin 18 and pin 24 of the chip U4 are connected to the driving chip 3U6 for outputting high or low level PWM signal; the pin 20 of the chip U4 is connected to the second NPN transistor T2 in the power supply unit 2, and the output control signal controls the power supply unit 2 to start or stop.

[0026] As shown in Figure 3 , the power supply unit 2 includes a first PNP transistor T1 and a second NPN transistor T2, which together constitute a switch tube to control the DC voltage output of the power supply unit 2. The DC power supply Vbat is connected to the emitter of the first PNP transistor T1, the collector of the first PNP transistor T1 outputs DC voltage, and the base of the first PNP transistor T1 is connected to the DC power supply Vbat, while the base of the first PNP transistor T1 is connected to the collector of the second NPN transistor T2, the emitter of the second NPN transistor T2 is connected to the ground, and the base of the second NPN transistor T2 is connected to the control chip 1. The working principle is that when the DC power supply Vbat is positive power input, the first PNP transistor T1 is turned on, the power supply unit 2 is in a conducting state to output DC voltage, and when the control chip 1 outputs a signal, the second NPN transistor T2 is turned on, the voltage at the base of the first PNP transistor T1 is pulled down, the first PNP transistor T1 is cut off, and the power supply unit 2 stops outputting the DC power supply Vbat.

[0027] As shown in Figure 3 , the power supply unit 2 further includes a third NPN transistor T3 and a voltage reduction chip U7. The first PNP transistor T1 and the second NPN transistor T2 constitute a switch tube structure to control the output of DC voltage, and the output DC voltage is marked as Vbus. The first PNP transistor T1 is connected to a resistor R1. The resistor R3 and a diode D1 are connected in series between the first PNP transistor T1 and the third NPN transistor T3. The anode of the diode D1 is connected to the collector of the third NPN transistor T3, the emitter of the third NPN transistor T3 is connected to the input end Vin of the voltage reduction chip U3, and the emitter of the third NPN transistor T3 is used as an output end to output DC voltage, and the output DC voltage is marked as VDrive. The base of the third NPN transistor T3 is connected to the anode of a voltage stabilizing diode DZ2, the cathode of the voltage stabilizing diode DZ2 is connected to the ground, a resistor R59 is connected between the collector and the base of the third NPN transistor T3, and the voltage stabilizing diode DZ2 keeps the output DC voltage VDrive stable. The voltage reduction chip U7 outputs 5V DC voltage.

[0028] As shown in Figure 3 the collector of the second NPN type triode T2 is connected to the anode of diode D5 and diode D9 respectively after connecting resistor R55, the cathode of diode D5 and diode D9 is connected to the port respectively, at the same time, the cathode of diode D5 is connected to the cathode of diode D6, the anode of diode D6 is connected to the control chip 1 after connecting resistor R85, the cathode of diode D9 is connected to the cathode of diode D10, the anode of diode D10 is connected to the control chip 1 after connecting resistor R65.

[0029] As shown in Figure 4 , the driving chip 3 in this embodiment is chip U6, the pins of chip U6 are connected to the corresponding pins of control chip 1, wherein the pin corresponding numbers are MWH, MVH, MUH, MWL, MVL, MUL respectively, the pins of driving chip 3 are connected to driving circuit 4, driving chip 3 outputs high level or low level signal to control the conduction of MOS tube in driving circuit 4, the pin corresponding numbers are LOU, LOV, LOW, HOU, HOV, HOW respectively, at the same time, the direct current voltage VDrive output by power supply unit 2 supplies power to driving chip 3; at the same time, diode D2 and capacitor C19, diode D3 and capacitor C21, diode D4 and capacitor C23 are used as bootstrap circuit to raise voltage.

[0030] Driving circuit 4 includes three-phase inverter bridge, which is composed of six MOS tubes, in this embodiment, the MOS tube is an eight pin MOS tube, and the six MOS tubes form an H type bridge arm, as shown in Figure 5 , the drain of MOS tube Q1, Q3, Q5 is connected to direct current power supply Vbat, the source of MOS tube Q1, Q3, Q5 is connected to the winding U, V, W end of brushless direct current motor as output terminal respectively, the gate of MOS tube Q1, Q3, Q5 is connected to the input signal of driving chip 3 to turn on the MOS tube, the gate of MOS tube Q1, Q3, Q5 is connected to HOU, HOV, HOW respectively, at the same time, the gate of MOS tube Q1 is connected to driving chip 3 with resistor R28, the gate of MOS tube Q1 is connected to the source with resistor R30, and the other MOS tubes Q3, Q5 are also connected with resistors. As shown in the figure, the drain of MOS tube Q2, Q4, Q6 is connected to the winding U, V, W end of brushless direct current motor as input terminal respectively, the source of MOS tube Q2, Q4, Q6 is connected to the grounding point, the gate of MOS tube Q2, Q4, Q6 is connected to LOU, LOV, LOW of driving chip 3 respectively, at the same time, the gate of MOS tube Q2, Q4, Q6 is connected to driving chip 3 with resistor, and the gate is connected to the source with resistor; in this way, the conduction of MOS tube in upper bridge arm and lower bridge arm drives the movement of brushless direct current motor.

[0031] As shown in Figure 5As shown, the source of MOS tube Q2, Q4, Q6 in the lower bridge arm is connected with sampling resistor CR1, sampling resistor CR1 is connected with acquisition circuit 5 in parallel, acquisition circuit 5 acquires motor current information in acquisition circuit 5 through sampling resistor CR1; simultaneously acquisition circuit 5 connects control chip 1 to output the acquired motor current information; as Figure 5 As shown, acquisition circuit 5 includes acquisition chip U5 and its attached circuit, the input end and the output end of acquisition chip U5 are connected with control chip 1 respectively, and the acquired current signal is transmitted to control chip 1 in real time, so that control chip 1 monitors the current information in the direct current motor circuit in real time.

[0032] The above is only the preferred embodiment of the present application, therefore, equivalent changes or modifications made according to the structure, features and principles described in the patent application range of the present application are included in the patent application range of the present application.

Claims

1. A brushless DC motor circuit for a tea plucker, characterised in that: It includes: The power supply unit outputs several direct current voltages to provide power for the control chip, the drive chip and the drive circuit respectively; the power supply unit includes a first PNP type transistor and a second NPN type transistor, the first PNP type transistor outputs direct current voltage, and the second NPN type transistor is connected to the base of the first PNP type transistor to receive a signal to control the first PNP type transistor to be cut off; The drive circuit includes a three-phase inverter bridge composed of six MOS tubes, which inverts direct current into alternating current and outputs to the brushless direct current motor; The drive chip is connected to the drive circuit to output signals to control the on-off of the MOS tube; The control chip outputs control signals to the drive chip to make the drive chip output specific signals to repeatedly turn on and off the MOS tube.

2. A brushless DC motor circuit for a tea plucker as claimed in claim 1 wherein: The emitter of the first PNP type transistor is connected to the direct current power supply Vbat, the collector of the first PNP type transistor outputs direct current voltage, and the emitter and the base of the first PNP type transistor are connected with a resistor R46, the base of the first PNP type transistor and the collector of the second NPN type transistor are connected with a resistor R53, and the emitter of the second NPN type transistor is connected to the ground.

3. A brushless DC motor circuit for a tea plucker as claimed in claim 2, wherein: The power supply unit further includes a third NPN type transistor and a voltage reduction chip, the collector of the third NPN type transistor is connected to the collector of the first PNP type transistor, and the emitter of the third NPN type transistor is connected to the voltage reduction chip.

4. A brushless DC motor circuit for a tea plucker as claimed in claim 3 wherein: The first PNP type transistor outputs direct current voltage Vbus, the third NPN type transistor outputs direct current voltage VDrive, and the voltage reduction chip outputs 5V direct current voltage.

5. A brushless DC motor circuit for a tea plucker as claimed in claim 4 wherein: The base of the third NPN type transistor is connected to the positive electrode of the stabilizing diode DZ2, the negative electrode of the stabilizing diode DZ2 is connected to the ground, and the collector and the base of the third NPN type transistor are connected with a resistor R59.

6. A brushless DC motor circuit for a tea plucker as claimed in claim 2, wherein: The collector of the second NPN type transistor is connected to a resistor R55, the resistor R55 is respectively connected to the positive electrodes of diodes D5 and D9, the negative electrodes of the diodes D5 and D9 are respectively connected to ports, the negative electrode of the diode D5 is connected to the negative electrode of the diode D6, the positive electrode of the diode D6 is connected to the resistor R85 and then connected to the control chip, the negative electrode of the diode D9 is connected to the negative electrode of the diode D10, and the positive electrode of the diode D10 is connected to the resistor R65 and then connected to the control chip.

7. A brushless DC motor circuit for a tea plucker as claimed in claim 1, wherein: The drive chip is connected with a bootstrap circuit.

8. A brushless DC motor circuit for a tea plucker as claimed in claim 1, wherein: The gates of the MOS tubes in the drive circuit are respectively connected to the drive chip, and the gates and the sources of the MOS tubes are respectively connected with resistors.

9. A brushless DC motor circuit for a tea plucker as claimed in claim 1, wherein: It further includes a collection circuit connected to the three-phase inverter bridge through a sampling resistor CR1.

10. A brushless DC motor circuit for a tea plucker as claimed in claim 9 wherein: The collection circuit includes a collection chip U5 and its auxiliary circuit, and the collection circuit is connected to the control chip in signal.

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