Self-locking protection circuit

Abstract

The utility model provides a self-locking protection circuit, which comprises a level trigger input module A, a level output module B and a trigger circuit module C. The level trigger input module A acquires a protection trigger signal, outputs level locking after passing through the trigger circuit module C, and then controls an enable port level signal of an external driving module through the level output module B, so that the protection trigger signal is output. And an EN enabling pin of the pre-driving module is locked, so that the driving module cannot automatically recover the rotation function of the motor. The self-locking protection circuit is simple in structure, can effectively protect motor abnormal output or motor stalling caused by failure of the MCU main control chip of the motor, locks the enabling end of the driving module once a protection signal is triggered, prevents abnormal motor output power, enables the motor to be shut down safely, and improves the safety of the motor. Personnel injury or motor burnout caused by repeated starting is avoided, a dual hardware protection mechanism is achieved, and the safety requirement is met.

Description

Technical Field

[0001] The utility model relates to a protection circuit, in particular to a self-locking protection circuit. Background Art

[0002] At present, the variable frequency motor products on the market, such as variable frequency wall breaking machines, generally lack locked hardware protection circuits and rely too much on MCU software detection for protection. The protection is single. Once the MCU is abnormal and cannot be protected by software, and the motor has an abnormally large power output or the motor is blocked, there will be a risk of endangering personnel or burning the motor or the entire machine. Currently, some integrated IPM modules or integrated pre-driver chip modules or driver MCUs have simple over-current protection, but the protection state cannot be locked. Once the over-current state disappears, the rotation state will be restored, which increases the risk factor of the product. Utility Model Content

[0003] In view of the deficiencies of the prior art, the utility model proposes a self-locking protection circuit, which can immediately shut down and keep the closed state once an abnormality occurs, preventing the motor from re-rotating to further increase the risk factor, and the power must be cut off to restart.

[0004] In order to implement the above technical solution, the utility model provides a self-locking protection circuit, including: a level trigger input module A, a level output module B and a trigger circuit module C, wherein the level trigger input module A obtains a protection trigger signal, outputs a level lock after passing through the trigger circuit module C, and then controls the enable port level signal of the external drive module through the level output module B to lock the EN enable pin of the pre-drive module, so that the drive module cannot restore the motor rotation function by itself.

[0005] Preferably, the trigger circuit module C includes transistors Q1, Q2, resistors R2, R3 and R4, and a capacitor C1, wherein the emitter of the transistor Q1 is connected to the power supply VCC, the collector of Q1 is connected to one end of the resistor R3, the other end of the resistor R3 is connected to the resistor R4, the other end of the resistor R4 is grounded, the base of Q1 is connected to one end of the resistor R2, the other end of the resistor R2 is respectively connected to the level trigger input module A, the level output module B and the collector of the transistor Q2, the emitter of the transistor Q2 is grounded, the base of the transistor Q2 is connected to the line connecting the resistors R3 and R4, one end of the capacitor C1 is connected to the base of the transistor Q2, and the other end is grounded.

[0006] Preferably, the level-triggered input module A comprises a resistor R1, one end of the resistor R1 is connected to the input signal, and the other end of the resistor R1 is connected to a line connecting a resistor R2 and a collector of a transistor Q2.

[0007] Preferably, the level output module B includes a diode D1, one end of which is connected to the resistor R1 and then connected to the line connecting the resistor R2 and the collector of the transistor Q2, and the other end of the diode D1 is connected to the EN enable pin of the pre-drive module.

[0008] The beneficial effect of a self-locking protection circuit provided by the utility model is that the self-locking protection circuit has a simple structure and can effectively protect the motor from abnormal output or motor stall caused by failure of the motor MCU main control chip. Once the protection signal is triggered, the enable end of the drive module is locked to prevent abnormal motor output power, allowing the motor to shut down safely to avoid personal injury or repeated starting and burning of the motor; and a dual hardware protection mechanism is implemented to meet safety regulations. BRIEF DESCRIPTION OF THE DRAWINGS

[0009] Figure 1 This is a circuit diagram of the utility model. DETAILED DESCRIPTION

[0010] The following will be combined with the drawings in the embodiments of the utility model to clearly and completely describe the technical solutions in the embodiments of the utility model. Obviously, the described embodiments are only part of the embodiments of the utility model, not all of the embodiments. All other embodiments obtained by ordinary personnel in this field without creative work are within the scope of protection of the utility model.

[0011] Embodiment: A self-locking protection circuit.

[0012] Reference Figure 1As shown, a self-locking protection circuit comprises: a level trigger input module A, a level output module B and a trigger circuit module C, wherein the trigger circuit module C comprises transistors Q1, Q2, resistors R2, R3 and R4, and a capacitor C1, wherein the emitter of the transistor Q1 is connected to a power supply VCC, the collector of Q1 is connected to one end of the resistor R3, the other end of the resistor R3 is connected to the resistor R4, the other end of the resistor R4 is grounded, the base of Q1 is connected to one end of the resistor R2, the other end of the resistor R2 is respectively connected to the level trigger input module A, the level output module B and the collector of the transistor Q2, and the emitter of the transistor Q2 is connected to the ... the power supply VCC, the collector of Q1 is connected to the power supply VCC, the collector of Q1 is connected to the power supply VCC, the collector of Q1 is connected to the power supply VCC, the collector of Q1 is connected to the power supply VCC, the collector of Q1 is connected to the power supply VCC, the collector of Q1 is connected to the power supply VCC The emitter is grounded, the base of the transistor Q2 is connected to the line where the resistors R3 and R4 are connected, one end of the capacitor C1 is connected to the base of the transistor Q2, and the other end is grounded, the level trigger input module A includes a resistor R1, one end of the resistor R1 is connected to the input signal, and the other end of the resistor R1 is connected to the line where the resistor R2 and the collector of the transistor Q2 are connected, and the level output module B includes a diode D1, one end of the diode D1 is connected to the resistor R1 and then connected to the line where the resistor R2 and the collector of the transistor Q2 are connected, and the other end of the diode D1 is connected to the EN enable pin of the pre-drive module. In actual operation, the level trigger input module A (resistor R1) in this circuit obtains the protection trigger signal from the pre-drive module, outputs the level lock after passing through the trigger circuit module C, and then controls the enable port level signal of the external drive module through the level output module B (diode D1), locks the EN enable pin of the pre-drive module, and prevents the drive module from automatically restoring the motor rotation function.

[0013] The self-locking protection circuit has a simple structure and can provide effective protection against abnormal motor output or motor stall caused by failure of the motor MCU main control chip. Once the protection signal is triggered, the enable end of the drive module is locked to prevent abnormal motor output power, allowing the motor to shut down safely to avoid personal injury or repeated starting and burning of the motor. It also implements a dual hardware protection mechanism to meet safety requirements.

[0014] The above is only a preferred embodiment of the present invention, but the present invention should not be limited to the contents disclosed in the embodiment and the drawings, so any equivalent or modification completed without departing from the spirit disclosed in the present invention shall fall within the scope of protection of the present invention.

Claims

1. A self-locking protection circuit, characterized in that include: Level trigger input module A, level output module B and trigger circuit module C, where level trigger input module A obtains the protection trigger signal, outputs the level lock after passing through the trigger circuit module C, and then controls the enable port level signal of the external drive module through the level output module B, locks the EN enable pin of the pre-drive module, and makes the drive module unable to restore the motor rotation function by itself.

2. The self-locking protection circuit according to claim 1, characterized in that: The trigger circuit module C includes transistors Q1, Q2, resistors R2, R3 and R4, and a capacitor C1, wherein the emitter of the transistor Q1 is connected to the power supply VCC, the collector of Q1 is connected to one end of the resistor R3, the other end of the resistor R3 is connected to the resistor R4, the other end of the resistor R4 is grounded, the base of Q1 is connected to one end of the resistor R2, the other end of the resistor R2 is respectively connected to the level trigger input module A, the level output module B and the collector of the transistor Q2, the emitter of the transistor Q2 is grounded, the base of the transistor Q2 is connected to the line connecting the resistors R3 and R4, one end of the capacitor C1 is connected to the base of the transistor Q2, and the other end is grounded.

3. The self-locking protection circuit according to claim 2, characterized in that: The level trigger input module A comprises a resistor R1 , one end of which is connected to the input signal, and the other end of which is connected to a line connecting a resistor R2 and a collector of a transistor Q2 .

4. The self-locking protection circuit according to claim 3, characterized in that: The level output module B includes a diode D1, one end of which is connected to the resistor R1 and then connected to the line connecting the resistor R2 and the collector of the transistor Q2, and the other end of the diode D1 is connected to the EN enable pin of the pre-drive module.

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