Electronic brake system based on photovoltaic output optocoupler

Abstract

The electronic brake system based on the photovoltaic output optocoupler comprises an MCU module, a driving circuit, a brake circuit, a driving motor and a motor power source, the motor power source is connected with the motor to form a power source circuit, and the input end of the driving circuit and the input end of the brake circuit are both electrically connected with the MCU module. The output end of the driving circuit is arranged on the power supply circuit, the output end of the brake circuit is connected with the two ends of a power supply of the driving motor in parallel, the input end of the brake circuit is provided with a photovoltaic output optocoupler device, the output end of the brake circuit is provided with an MOS (Metal Oxide Semiconductor) tube, the MCU module switches on the photovoltaic output optocoupler device by outputting a brake signal, so that the MOS tube is switched on, and the driving motor is short-circuited. And the driving motor is stopped. Compared with the prior art, the electronic brake system can be started for a long time under the condition that an external power supply is not needed, the cost is lower, the circuit structure is simple, and the miniaturization design of the circuit is facilitated.

Description

Technical Field

[0001] The utility model relates to the field of industrial robots, and in particular to an electronic brake system based on photovoltaic output optical coupling. Background Art

[0002] With the vigorous development and widespread application of AGV handling robot technology, AGV is increasingly used in various factory scenarios. Among them, the drive of the hook lifting motor is also increasingly widely used. The common hook lifting motor drive is a high-power open-drain output drive type that works with a limit switch. A typical drive diagram is shown below: Figure 3 As shown, in order to avoid the motor state vibrating to an unexpected position during the operation of the AGV, they need to add a braking function to enhance controllability when they are stationary. Existing braking methods all have their own disadvantages. For example, the motor with its own brake coil will increase the cost and volume of the motor, and it is also more complicated to apply. Although the electronic brake system improved to a relay can simplify the circuit and reduce the submission, it will also bring problems such as spark interference and contact wear, and the durability is not good. Although the bootstrap drive method drives the MOS tube without the problem of spark interference and contact wear, it cannot maintain the upper arm conduction for a long time 100% because of the need to charge the bootstrap capacitor, and loses the meaning of long-term braking. Finally, through the isolation optocoupler drive MOS tube + isolated power supply method, although it can be turned on for a long time, because of the application of isolated power supply, the circuit is complex and the cost is high, which is not conducive to the miniaturization of the control circuit.

[0003] Based on the above, if a brake control circuit can be designed that can be turned on for a long time but does not require an isolated power supply, it can effectively reduce costs and facilitate circuit miniaturization design. Summary of the invention

[0004] The invention aims to solve the problems of various drawbacks in the existing AGV braking methods and to provide an electronic braking system based on photovoltaic output optocouplers.

[0005] In order to achieve the above invention objectives, the utility model adopts the following technical solutions:

[0006] The electronic brake system based on photovoltaic output optocoupler includes an MCU module, a drive circuit, a brake circuit, a drive motor and a motor power supply. The motor power supply is connected to the motor to form a power supply circuit. The input ends of the drive circuit and the brake circuit are electrically connected to the MCU module. The output end of the drive circuit is arranged on the power supply circuit. The output end of the brake circuit is connected in parallel with the two ends of the power supply of the drive motor. The input end of the brake circuit is provided with a photovoltaic output optocoupler device, and the output end is provided with a MOS tube. The MCU module turns on the photovoltaic output optocoupler device by outputting a brake signal to turn on the MOS tube, and the drive motor is short-circuited, so that the drive motor stops moving.

[0007] The utility model adopts a photovoltaic output optocoupler device. When the MCU module outputs a brake signal, the input end of the photovoltaic output optocoupler device emits light. When the photovoltaic output end is irradiated, it is turned on due to the photovoltaic effect and generates a voltage that turns on the MOS tube, turning on the MOS tube and short-circuiting the two ends of the drive motor. Compared with the prior art, the photovoltaic output optocoupler device of the utility model can provide a conduction voltage for the MOS tube. Therefore, the output end of the brake circuit does not need an external power supply. In the absence of an external power supply, it can be turned on for a long time, with lower cost and simple circuit structure, which is conducive to the miniaturization design of the circuit.

[0008] Furthermore, the brake circuit is a high-side drive output circuit.

[0009] Furthermore, the brake circuit includes a 3.3V power supply, which is connected in parallel with the current input interface of the input end of the photovoltaic output optocoupler device. The MCU module drives the input end of the photovoltaic output optocoupler device to conduct by outputting a low-level signal to the current output interface of the photovoltaic output optocoupler device, and vice versa. In this solution, when the MCU module outputs a high-level signal, the voltages at both ends of the light-emitting diode at the input end of the photovoltaic output optocoupler device are equal, causing it to be non-conductive; when the MCU module outputs a low-level signal, the voltage at the input end of the photovoltaic output optocoupler device is higher than the current output end, so that it is conductive.

[0010] Furthermore, a first current limiting resistor is connected in series between the MCU module and the current output terminal of the photovoltaic output optocoupler device.

[0011] Furthermore, the driving circuit is a low-side open-drain output driving circuit.

[0012] Furthermore, the brake circuit is also provided with a switching diode, a bipolar junction transistor, a first voltage-dividing resistor and a second voltage-dividing resistor. The current input interface of the output end of the photovoltaic output optocoupler device is electrically connected to the electrode of the MOS tube through the switching diode, the two ends of the first voltage-dividing resistor are connected in parallel with the switching diode, the second voltage-dividing resistor is connected in parallel with the output end of the photovoltaic output optocoupler device, the base of the bipolar junction transistor is connected in parallel between the current input interface of the output end of the photovoltaic output optocoupler device and the switching diode, the emitter is connected in parallel between the switching diode and the MOS tube, and the collector is connected in parallel between the source of the MOS tube. When the photovoltaic output end of the optocoupler is irradiated, due to the photovoltaic effect, a power source output of not less than 7V / 12uA can be generated. By connecting the external shunt resistor R23 in parallel, a voltage source and a pull-down effect are generated, and then the upper arm Q4 is directly driven to be turned on through D6, which has both isolation and isolated power supply. The floating ground can be superimposed on the D pole of Q6, so Q4 can be maintained in the on state for a long time; at this time, R21 and Q5 are inverted PN junctions, and Q5 is not turned on; 5. When the output end of the optocoupler is not irradiated, there is no irradiated power output at the output end of U6, and the voltage divider resistor composed of R23 and R21 makes the PN junction of Q5 forward biased, Q5 is turned on, and the charge charged at the gs end of Q4 is quickly released through the ce junction of Q5, thereby achieving the effect of quickly shutting down Q4.

[0013] Furthermore, the bipolar junction transistor is of N type.

[0014] Furthermore, the MOS tube is an N-channel MOS tube.

[0015] Furthermore, the output current of the photovoltaic output optocoupler device is greater than 7V / 12uA.

[0016] Furthermore, the photovoltaic output optocoupler device is of TLP3906 type. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 It is a schematic diagram of the principle of the electronic brake system;

[0018] Figure 2 It is the circuit diagram of the electronic brake system;

[0019] Figure 3 It is a schematic diagram of the principle of the existing electronic brake system.

[0020] Description of labels:

[0021] MCU module, drive circuit 2, brake circuit 1, drive motor M, motor power supply B, first current limiting resistor R22, switch diode D6, bipolar junction transistor Q5, first voltage dividing resistor R22, second voltage dividing resistor R23, MOS tube Q5. DETAILED DESCRIPTION

[0022] The technical solution of the utility model is further described below according to the accompanying drawings:

[0023] See also Figure 1-2 As shown, the electronic brake system based on photovoltaic output optocoupler includes an MCU module, a drive circuit 2, a brake circuit 1, a drive motor M and a motor power supply B. The motor power supply B is connected to the motor to form a power supply circuit. The input ends of the drive circuit 2 and the brake circuit 1 are electrically connected to the MCU module. The output end of the drive circuit 2 is arranged on the power supply circuit. The output end of the brake circuit 1 is connected in parallel with the two ends of the power supply of the drive motor M. The input end of the brake circuit 1 is provided with a photovoltaic output optocoupler device, and the output end is provided with a MOS tube Q5. The MCU module turns on the photovoltaic output optocoupler device by outputting a brake signal, so that the MOS tube Q5 is turned on, and the drive motor M is short-circuited, so that the drive motor M stops moving.

[0024] Furthermore, the brake circuit 1 is a high-side drive output circuit.

[0025] Furthermore, the brake circuit includes a 3.3V power supply, which is connected in parallel with the current input interface of the input end of the photovoltaic output optocoupler device. The MCU module drives the input end of the photovoltaic output optocoupler device to conduct by outputting a low-level signal to the current output interface of the photovoltaic output optocoupler device, and vice versa. In this solution, when the MCU module outputs a high-level signal, the voltages at both ends of the light-emitting diode at the input end of the photovoltaic output optocoupler device are equal, causing it to be non-conductive; when the MCU module outputs a low-level signal, the voltage at the input end of the photovoltaic output optocoupler device is higher than the current output end, so that it is conductive.

[0026] Furthermore, a first current limiting resistor R22 is connected in series between the MCU module and the current output end of the photovoltaic output optocoupler device.

[0027] Furthermore, the driving circuit 2 is a low-side open-drain output driving circuit 2.

[0028] Furthermore, the brake circuit 1 is also provided with a switching diode D6, a bipolar junction transistor Q5, a first voltage-dividing resistor R22 and a second voltage-dividing resistor R23. The current input interface of the output end of the photovoltaic output optocoupler device is electrically connected to the electrode of the MOS tube Q5 through the switching diode D6. The two ends of the first voltage-dividing resistor R22 are connected in parallel with the switching diode D6, and the second voltage-dividing resistor R23 is connected in parallel with the output end of the photovoltaic output optocoupler device. The base of the bipolar junction transistor Q5 is connected in parallel between the current input interface of the output end of the photovoltaic output optocoupler device and the switching diode D6, its emitter is connected in parallel between the switching diode D6 and the MOS tube Q5, and the collector is connected in parallel between the source of the MOS tube Q5.

[0029] Furthermore, the bipolar junction transistor Q5 is of N type.

[0030] Furthermore, the MOS transistor Q5 is an N-channel MOS transistor Q5.

[0031] Furthermore, the output current of the photovoltaic output optocoupler device is greater than 7V / 12uA.

[0032] Furthermore, the photovoltaic output optocoupler device is of TLP3906 type.

[0033] The utility model adopts a photovoltaic output optocoupler device. When the MCU module outputs a brake signal, the input end of the photovoltaic output optocoupler device emits light. When the photovoltaic output end is irradiated, it is turned on due to the photovoltaic effect, and a voltage is generated to turn on the MOS tube Q5, so that the MOS tube Q5 short-circuits the two ends of the motor. The photovoltaic output optocoupler device of the utility model can provide a conduction voltage for the MOS tube Q5. Therefore, the output end of the brake circuit 1 does not need an external power supply. In the absence of an external power supply, it can be turned on for a long time, the cost is lower, the circuit structure is simple, and it is conducive to the miniaturization design of the circuit.

[0034] In this specification, each embodiment is described in a progressive manner, and each embodiment focuses on the differences from other embodiments, and the same and similar parts between the embodiments can be referred to each other. According to the disclosure and teaching of the above specification, technicians in the field to which the utility model belongs can also change and modify the above implementation. Therefore, the utility model is not limited to the specific implementation methods disclosed and described above, and some modifications and changes to the utility model should also fall within the scope of protection of the claims of the utility model. In addition, although some specific terms are used in this specification, these terms are only for the convenience of description and do not constitute any limitation to the utility model.

Claims

1. An electronic brake system based on photovoltaic output optocoupler, characterized in that: It includes an MCU module, a driving circuit, a brake circuit, a driving motor and a motor power supply. The motor power supply is connected to the driving motor to form a power supply circuit. The input ends of the driving circuit and the brake circuit are electrically connected to the MCU module. The output end of the driving circuit is arranged on the power supply circuit. The output end of the brake circuit is connected in parallel with the two ends of the power supply of the driving motor. The input end of the brake circuit is provided with a photovoltaic output optocoupler device, and the output end is provided with a MOS tube. The MCU module turns on the photovoltaic output optocoupler device by outputting a brake signal to turn on the MOS tube, and the driving motor is short-circuited, so that the driving motor stops moving.

2. The electronic brake system according to claim 1, characterized in that: The brake circuit is a high-side drive output circuit.

3. The electronic brake system according to claim 2, characterized in that: The brake circuit includes a 3.3V power supply, which is connected in parallel with the current input interface of the input end of the photovoltaic output optocoupler device. The MCU module drives the input end of the photovoltaic output optocoupler device to be turned on by outputting a low-level signal to the current output interface of the photovoltaic output optocoupler device, and vice versa.

4. The electronic brake system according to claim 3, characterized in that: A first current limiting resistor is connected in series between the MCU module and the current output end of the photovoltaic output optocoupler device.

5. The electronic brake system according to claim 2, characterized in that: The driving circuit is a low-side open-drain output driving circuit.

6. The electronic brake system according to claim 5, characterized in that: The brake circuit is also provided with a switching diode, a bipolar junction transistor, a first voltage-dividing resistor and a second voltage-dividing resistor. The current input interface at the output end of the photovoltaic output optocoupler device is electrically connected to the electrodes of the MOS tube through the switching diode. The two ends of the first voltage-dividing resistor are connected in parallel with the switching diode, and the second voltage-dividing resistor is connected in parallel with the output end of the photovoltaic output optocoupler device. The base of the bipolar junction transistor is connected in parallel between the current input interface at the output end of the photovoltaic output optocoupler device and the switching diode, the emitter is connected in parallel between the switching diode and the MOS tube, and the collector is connected in parallel between the source of the MOS tube.

7. The electronic brake system according to claim 6, characterized in that: The bipolar junction transistor is of N type.

8. The electronic brake system according to claim 5, characterized in that: The MOS tube is an N-channel MOS tube.

9. The electronic brake system according to claim 5, characterized in that: The output current of the photovoltaic output optocoupler device is greater than 7V / 12uA.

10. The electronic brake system according to claim 5, characterized in that: The photovoltaic output optocoupler device is of TLP3906 type.

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