CN217509419U

CN217509419U - Self-locking circuit and lawn mower

Info

Publication number: CN217509419U
Application number: CN202221204923.5U
Authority: CN
Inventors: 王志; 卢朝杰
Original assignee: Shenzhen Topband Co Ltd
Current assignee: Shenzhen Topband Co Ltd
Priority date: 2022-05-18
Filing date: 2022-05-18
Publication date: 2022-09-30
Anticipated expiration: 2032-05-18

Abstract

The utility model is suitable for an electrical equipment technical field provides a self-locking circuit and lawn mower, and the circuit includes drive control module, load drive module, load detection module, voltage regulation module, feedback self-locking module and auto-lock release module. This application detects the operating condition of load and exports to voltage regulation module through load detection module, voltage regulation module can adjust drive control module's input voltage, and then make auto-lock feedback module with voltage regulation module auto-lock when the control signal of drive control module output satisfies the preset condition at the target state, realize the auto-lock function, can also feed back auto-lock module and withdraw from the target state through auto-lock release module when loosening starting switch, thereby awaken load work once more, thereby avoid taking place load or circuit damage and the like unexpected condition that leads to taking place load or circuit under load takes place abnormal conditions and continue to control load work, protect load and circuit safety.

Description

Self-locking circuit and lawn mower

Technical Field

The utility model belongs to the technical field of electrical equipment, especially, relate to a self-locking circuit and lawn mower.

Background

The mower is a mechanical tool for trimming lawns, vegetations and the like, and consists of a cutter head, an engine, traveling wheels, a traveling mechanism, blades, handrails and a control part, and the blades are driven by a sender to rotate at a high speed to quickly trim plants, so that the operation time of weeders is saved, and a large amount of manpower resources are reduced.

In the working process of the mower, if an accident occurs, there is a risk of causing the motor or other driving circuits to work under the condition of recognizing the abnormality, for example, the starting switch continuously presses the motor to work, and when the controller or the motor has the abnormal conditions of overcurrent, overvoltage, undervoltage or high temperature, the controller chip still outputs the PWM signal to cause the motor to continuously work abnormally, which causes the circuit or the motor to be abnormal or damaged.

SUMMERY OF THE UTILITY MODEL

The utility model provides a self-locking circuit aims at solving among the prior art lawn mower's controller and presses starting switch after, has motor or other drive circuit to continue work under discernment abnormal conditions and leads to unusual or damaged problem.

The embodiment of the present invention is implemented as follows, and a self-locking circuit includes:

the driving control module is connected with the main control chip and receives the driving signal output by the main control chip to output a control signal;

the load driving module is connected with the driving control module, the normally open end of the starting switch and the load and receives a control signal to switch on or off the connection between the normally open end of the starting switch and the load;

the load detection module is connected with the load driving module and used for detecting the working state of the load and outputting a detection signal;

the voltage regulation module is connected with the drive control module and the load detection module and receives the detection signal to regulate the input voltage of the drive control module;

the feedback self-locking module is connected with the drive control module and the voltage regulation module, receives the control signal output by the drive control module, and outputs a self-locking signal to the voltage regulation module when the control signal meets a preset condition so as to enable the voltage regulation module to be in a target state;

and the self-locking release module is connected with the normally closed end of the starting switch and the feedback self-locking module, receives the normally closed signal output by the normally closed end to output a release signal to the feedback self-locking module, so that the feedback self-locking module stops outputting the self-locking signal.

Optionally, the self-locking circuit further comprises:

and the voltage detection module is connected with the main control chip and the load driving module, receives a voltage division signal of the voltage division resistor in the load driving module and outputs the voltage division signal to the main control chip so as to enable the main control chip to stop outputting the level of the driving signal.

Optionally, the driving control module includes a driving chip, a first resistor, a second resistor, a third resistor, a first capacitor, a second capacitor, and a first diode;

the driving chip comprises a chip voltage pin, a first input pin, a second input pin, a high-end floating power supply voltage pin, a high-end floating power supply offset voltage pin, a high-end output pin, a low-end output pin and a grounding pin;

the chip voltage pin is grounded through a first capacitor, the chip voltage pin is also connected with the anode of a first diode through a first resistor, and the cathode of the first diode is connected with the high-end floating power supply voltage pin;

the first input pin is connected with a first signal output end of the main control chip through a second resistor;

the second input pin is connected with a second signal output end of the main control chip through a third resistor;

a high-end floating power supply offset voltage pin, a high-end output pin, a low-end output pin and a load driving module;

the high-end output pin is also connected with the feedback self-locking module;

the high-end floating power supply voltage pin is connected with the high-end floating power supply offset voltage pin through a second capacitor;

the power connection pin is grounded.

Optionally, the load driving module includes a first switch tube, a second switch tube, a fourth resistor, a fifth resistor, a sixth resistor, a seventh resistor, an eighth resistor, a ninth resistor, a tenth resistor, a third capacitor, a fourth capacitor, a fifth capacitor, a second diode, a third diode, a fourth diode, and a fifth diode;

a first pole pin of the first switch tube is connected with a normally-open end of the starting switch, a second pole pin is connected with one end of the fourth resistor, and a third pole pin is connected with the driving control module, a first pole pin of the second switch tube and a first end of the load;

one end of a fourth resistor is connected with one end of the third capacitor, the anode of the second diode and the cathode of the third diode, and the other end of the fourth resistor is connected with the driving control module;

the cathode of the second diode is connected with the other end of the fourth resistor through a fifth resistor;

the other end of the third capacitor and the anode of the third diode are both connected with a third pin of the first switch tube;

the sixth resistor is connected with the third capacitor in parallel;

the first end of the load is connected with the second end of the load through a fourth capacitor, and the second end of the load is grounded through a seventh resistor;

a second diode pin of the second switch tube is connected with one end of an eighth resistor, one end of a fifth capacitor, the anode of a fourth diode and the cathode of a fifth diode, and a third diode pin is grounded;

the other end of the eighth resistor is connected with the driving control module;

the cathode of the fourth diode is connected with the other end of the eighth resistor through a ninth resistor;

the other end of the fifth capacitor and the anode of the fifth diode are connected with a third pin of the second switch tube;

and the tenth resistor is connected with the fifth capacitor in parallel.

Optionally, the load detection module includes a third switching tube, an eleventh resistor, a twelfth resistor, a thirteenth resistor, a fourteenth resistor, a sixth capacitor, a seventh capacitor, a sixth diode, and a seventh diode;

a first pole pin of the third switching tube is connected with the load driving module, a second pole pin of the third switching tube is connected with one end of the eleventh resistor and one end of the twelfth resistor, and a third pole pin of the third switching tube is connected with one end of the thirteenth resistor and one end of the fourteenth resistor;

the other end of the eleventh resistor is connected with the first voltage end;

the other end of the twelfth resistor is grounded;

the other end of the thirteenth resistor is connected with the second voltage end;

the other end of the fourteenth resistor is connected with one end of the sixth capacitor, the anode of the sixth diode and the anode of the seventh diode;

the other end of the sixth capacitor is grounded;

the cathode of the sixth diode is connected with the first voltage end;

the cathode of the seventh diode is connected with the voltage regulating module;

and the seventh capacitor is connected with the twelfth resistor in parallel.

Optionally, the voltage regulation module includes a fourth switching tube, a fifteenth resistor, a sixteenth resistor and an eighth capacitor;

a first pole pin of the fourth switch tube is connected with the driving control module, a second pole pin is connected with one end of a fifteenth resistor and one end of a sixteenth resistor, and a third pole pin is grounded;

the other end of the fifteenth resistor is connected with the load detection module and the feedback self-locking module;

the other end of the sixteenth resistor is grounded;

the eighth capacitor is connected in parallel with the sixteenth resistor.

Optionally, the feedback self-locking module includes a fifth switch tube, a sixth switch tube, a seventeenth resistor, an eighteenth resistor, a nineteenth resistor, a twentieth resistor, a twenty-first resistor, a ninth capacitor, a tenth capacitor, an eighth diode, a ninth diode, and a twelfth diode;

a first pole pin of the fifth switch tube is connected with the load driving module, a second pole pin of the fifth switch tube is connected with one end of a seventeenth resistor, and a third pole pin of the fifth switch tube is connected with one end of an eighteenth resistor;

the other end of the seventeenth resistor is connected with the anode of the eighth diode, and the cathode of the eighth diode is connected with the normally-open end of the starting switch;

the other end of the eighteenth resistor is connected with the second pole pin of the sixth switching tube, one end of the nineteenth resistor and the cathode of the ninth diode;

a first pole pin of the sixth switching tube is connected with the self-locking release module, one end of the twentieth resistor, one end of the twenty-first resistor and one end of the ninth capacitor, and a third pole pin is grounded;

the other end of the nineteenth resistor, the anode of the ninth diode and the other end of the ninth capacitor are grounded;

the other end of the twentieth resistor is connected with the second voltage end;

the other end of the twenty-first resistor is connected with the anode of a twelfth pole tube, and the cathode of the twelfth pole tube is connected with the voltage regulating module;

and the tenth capacitor is connected with the nineteenth resistor in parallel.

Optionally, the self-locking release module includes a seventh switch tube, a twenty-second resistor, a twenty-third resistor, a twenty-fourth resistor, a twenty-fifth resistor, a twenty-sixth resistor, a twenty-seventh resistor, a twenty-eighth resistor, an eleventh capacitor, an eleventh diode, and a twelfth diode;

a first pole tube pin of the seventh switch tube is connected with the feedback self-locking module through a twelfth resistor, a second pole tube pin is connected with one end of a twenty-third resistor and one end of a twenty-fourth resistor, and a third pole tube pin is grounded;

the other end of the twenty-third resistor is grounded;

the other end of the twenty-fourth resistor is connected with one end of the twenty-fifth resistor, one end of the eleventh capacitor and the anode of the eleventh diode;

the other end of the twenty-fifth resistor is connected with one end of the twenty-sixth resistor and the other end of the twenty-seventh resistor;

the other end of the eleventh capacitor and the other end of the twenty-sixth resistor are grounded;

the cathode of the eleventh diode is connected with the first voltage end;

the other end of the twenty-seventh resistor is connected with the cathode of the twelfth diode;

the anode of the twelfth diode is connected with one end of the twenty-eighth resistor;

the other end of the twenty-eighth resistor is connected with the normally-closed end of the starting switch.

Optionally, the voltage detection module includes an operational amplifier, a twenty-ninth resistor, a thirty-th resistor, a thirty-first resistor, a thirty-second resistor, and a twelfth capacitor;

the non-inverting input end of the operational amplifier is connected with one end of the twenty-ninth resistor and one end of the twelfth capacitor, the inverting input end of the operational amplifier is connected with one end of the thirty-first resistor, one end of the thirty-first resistor and the other end of the twelfth capacitor, and the output end of the operational amplifier is connected with the other end of the thirty-first resistor and one end of the thirty-second resistor;

the other end of the twenty-ninth resistor is connected with one end of the divider resistor;

the other end of the thirtieth resistor is connected with the other end of the divider resistor;

and the other end of the thirty-second resistor is connected with the main control chip.

In a second aspect, the present application also provides a lawn mower comprising a self-locking circuit as described above.

The embodiment of the utility model provides an output drive signal to the drive control module through the main control chip, so that the drive control module outputs control signal to the load drive module to turn on or off the connection between the normally open end of the start switch and the load, simultaneously detect the working state of the load through the load detection module and output to the voltage regulation module, the voltage regulation module can regulate the input voltage of the drive control module, further make the self-locking feedback module output self-locking signal when the control signal output by the drive control module meets the preset condition, so as to self-lock the voltage regulation module in the target state, realize the self-locking function, can also output release signal after receiving the normally closed signal through the self-locking release module, so that the feedback self-locking module stops outputting self-locking signal, thereby awakening the load work again, thereby avoiding the load work under the abnormal condition of the load and causing the unexpected conditions such as load or circuit damage, protecting the load and the circuit safety.

Drawings

FIG. 1 is a schematic block diagram of a self-locking circuit according to an embodiment of the present application;

FIG. 2 is a schematic block diagram of another embodiment of a self-locking circuit of the present application;

FIG. 3 is a schematic circuit diagram of an embodiment of a self-locking circuit of the present application;

fig. 4 is a schematic circuit diagram of another embodiment of the self-locking circuit of the present application.

Detailed Description

In order to make the objects, technical solutions and advantages of the present invention more clearly understood, the present invention is further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the invention and are not intended to limit the invention.

The load protection method and the load protection device can avoid the unexpected situations that the load or a circuit is damaged and the like caused by the fact that the load is continuously controlled to work under the abnormal situation of the load, and protect the safety of the load and the circuit.

Example one

In some alternative embodiments, as shown in fig. 1-4, the present application provides a self-locking circuit comprising:

the drive control module 100 is connected with the main control chip U1 and receives the drive signal output by the main control chip U1 to output a control signal;

the load driving module 200 is connected with the driving control module 100, the normally-open end NO of the starting switch U2 and the load U3, and receives a control signal to turn on or off the connection between the normally-open end NO of the starting switch U2 and the load U3;

the load detection module 300 is connected with the load driving module 200, and is used for detecting the working state of the load U3 and outputting a detection signal;

a voltage adjusting module 400 connected to the driving control module 100 and the load detecting module 300, for receiving the detection signal to adjust the input voltage of the driving control module 100;

the feedback self-locking module 500 is connected with the driving control module 100 and the voltage regulating module 400, receives the control signal output by the driving control module 100, and outputs a self-locking signal to the voltage regulating module 400 when the control signal meets a preset condition, so that the voltage regulating module 400 is in a target state;

the self-locking release module 600 is connected to the normally closed end NC of the start switch U2 and the feedback self-locking module 500, and receives a normally closed signal output by the normally closed end NC to output a release signal to the feedback self-locking module 500, so that the feedback self-locking module 500 stops outputting a self-locking signal.

In implementation, the main control chip U1 is a single chip, and the main control chip U1 can output a PWM signal to the driving control module 100 to control the load U3 to operate, optionally, the load U3 refers to a functional element or a component in the electrical equipment, for example, the load U3 includes but is not limited to a motor, a resistor, a coil, or the like, and is not limited herein. When receiving the driving signal output by the main control chip U1, the driving control module 100 outputs a corresponding control signal to the load driving module 200 according to the driving signal.

Optionally, the load driving module 200 is connected to the output end of the driving control module 100 to receive the control signal output by the driving control module 100, and turns on or off the connection between the normally open end NO of the starting switch U2 and the load U3 according to the control signal; optionally, the start switch U2 includes a normally open end NO, a normally closed end NC and a common end COM, where the common end COM is connected to the bus voltage VCC, and when the start switch U2 is pressed, the normally open end NO is connected to the common end COM, the start switch U2 is in a normally open state, and the normally open end NO may output the voltage of the bus voltage VCC; when the starting switch U2 is released, the normally closed terminal NC is connected to the common terminal COM, the starting switch U2 is in a normally closed state, and the normally closed terminal NC can output the voltage of the bus voltage VCC.

In operation, when the device presses the start switch U2, the start switch U2 enters a normally open state to output voltage to the load U3 through a normally open end NO to drive the load U3 to operate.

The load driving module 200 may turn on the connection between the normally open end NO and the load U3 to operate the load U3, and in other embodiments, the load driving module 200 may turn off the connection between the normally open end NO and the load U3 to stop the load U3.

In general, the main control chip U1 outputs a PWM signal to the driving control module 100, so that the driving control module 100 outputs a control signal for normal operation to the load driving module 200, and the load driving module 200 controls the load U3 to operate according to the control signal. Then, the load detection module 300 detects the operating state of the load U3, and outputs a detection signal corresponding to the operating state of the load U3 to the voltage regulation module 400, optionally, the operating state of the load U3 includes a normal operating state and an abnormal operating state, so that the voltage regulation module 400 can regulate the input voltage of the drive control module 100 according to the detection signal output by the load detection module 300, for example, taking the PWM signal output by the main control chip U1 as a high level signal, at this time, the input end of the drive control module 100 is at a high level, so as to output a control signal for controlling the normal operation of the load U3. In some embodiments, for example, the control signal for controlling the normal operation of the load U3 may be set to be a high level signal, the load driving module 200 turns on the connection between the normally open end NO and the load U3 after receiving the high level control signal output by the driving control module 100, the load U3 starts to operate normally, the load detecting module 300 detects the operating state of the load U3 and outputs a detection signal to the voltage regulating module 400, the voltage regulating module 400 maintains the input end of the driving control module 100 at a high level, and the load U3 continues to operate normally.

When the load U3 works abnormally, the load detection module 300 outputs a detection signal indicating that the load U3 works abnormally to the voltage regulation module 400, so that the voltage regulation module 400 sets the input voltage of the driving control module 100 low, and further, the driving control module 100 outputs a low-level control signal for controlling the load U3 to stop working, and cuts off the connection between the normally open end NO and the load U3, so as to control the load U3 to stop working, and simultaneously, the feedback self-locking module 500 detects the control signal output by the driving control module 100 and compares the control signal with a preset electrical signal, wherein the preset electrical signal is a low-level signal, that is, when the feedback self-locking module 500 detects that the control signal output by the driving control module 100 is a low-level signal, a preset condition is satisfied, the feedback self-locking module 500 outputs a self-locking signal to the voltage regulation module 400 to self-lock the voltage regulation module 400 in a target state, optionally, the target state is a state of setting the input voltage of the driving control module 100 to be low, and at this time, even though the main control chip U1 still outputs the PWM signal of the high level to the input end of the driving control module 100, the input end of the driving control module 100 is still set to be low under the action of the voltage adjusting module 400, so that the driving control module 100 continuously outputs the control signal of the low level, thereby continuously controlling the load U3 to stop working, and implementing the self-locking function.

In other embodiments, after the user releases the start switch U2, the start switch U2 enters a normally closed state, and the normally closed end of the start switch U2 outputs a voltage, so that the self-locking release module 600 outputs a release signal to the feedback self-locking module 500 after receiving the normally closed signal output by the normally closed end, so that the feedback self-locking module 500 stops outputting the self-locking signal, and the voltage regulation module 400 exits the target state to release the state where the input voltage to the driving control module 100 is low, when the user presses the start switch U2 again, the main control chip U1 outputs a PWM signal to the driving control module 100, so that the input voltage to the driving control module 100 is at a high level, and the driving control module 100 outputs a high-level control signal, thereby controlling the load U3 to operate normally.

It should be noted that, the control signal and the preset electrical signal are at a high level or a low level as an example of an embodiment of the present application, and in implementation, the control signal and the preset electrical signal may be specifically set according to circuit parameters, and are not specifically limited herein.

The embodiment of the present invention outputs a driving signal to the driving control module 100 through the main control chip U1, so that the driving control module 100 outputs a control signal to the load driving module 200 to turn on or turn off the connection between the normally open end NO of the start switch U2 and the load U3, and simultaneously, the load detection module 300 detects the working state of the load U3 and outputs the working state to the voltage regulation module 400, the voltage regulation module 400 can adjust the input voltage of the driving control module 100, so that the self-locking feedback module 500 outputs a self-locking signal when the control signal output by the driving control module 100 meets the preset condition, so as to self-lock the voltage regulation module 400 in a target state, thereby realizing the self-locking function, and further, the self-locking release module 600 can output a release signal after receiving the normally closed signal, so as to make the feedback self-locking module 500 stop outputting the self-locking signal, thereby waking up the load U3 to work again, therefore, accidents such as load U3 or circuit damage caused by continuous control of the load U3 under the abnormal condition of the load U3 are avoided, and the load U3 and the circuit are protected from being damaged.

Example two

In some optional embodiments, as shown in fig. 2, the self-locking circuit provided by the present application further includes:

the voltage detection module 700 is connected to the main control chip U1 and the load driving module 300, and receives a voltage division signal of the voltage division resistor in the load driving module 300 and outputs the voltage division signal to the main control chip U1, so that the main control chip U1 stops outputting the driving signal.

In implementation, when the load U3 works abnormally, the current of the load driving module 300 changes, for example, taking the load U3 as a motor as an example, when the motor is locked, the current of the load driving module 300 increases, so that the divided voltage of the voltage dividing resistor increases, the voltage detection module 700 detects that the divided voltage of the divided voltage increases and outputs the voltage to the main control chip U1, the main control chip U1 determines that the load U3 is abnormal, so as to stop outputting the driving signal, for example, the main control chip U1 stops outputting the PWM signal, at this time, the input end of the driving control module 100 is at a low level, so that the driving control module 100 outputs a low level to the load driving module 200, so that the load driving module 200 cuts off the connection between the normally open end NO and the load U3, and further controls the load U3 to stop working. Meanwhile, when the feedback self-locking module 500 detects that the driving control module 100 outputs a low-level control signal, the feedback self-locking module enters a self-locking mode to self-lock the voltage regulation module 400 in a target state where the input voltage of the driving control module 100 is set low, so that the input end of the driving control module 100 is continuously set low, and the driving control module 100 continuously outputs a low-level control signal to continuously control the load U3 to stop working, thereby implementing a self-locking function.

EXAMPLE III

In some alternative embodiments, as shown in fig. 3, the driving control module 100 includes a driving chip U4, a first resistor R1, a second resistor R2, a third resistor R3, a first capacitor C1, a second capacitor C2, and a first diode D1;

the driving chip U4 includes a chip voltage pin Vcc, a first input pin HIN, a second input pin LIN, a high-side floating power supply voltage pin VB, a high-side floating power supply offset voltage pin VS, a high-side output pin HO, a low-side output pin LO, and a ground pin Com;

the chip voltage pin Vcc is grounded through a first capacitor C1, the chip voltage pin Vcc is also connected with the anode of a first diode D1 through a first resistor R1, and the cathode of the first diode D1 is connected with a high-end floating power supply voltage pin VB;

the first input pin HIN is connected with a first signal output end PWM _ H of the main control chip U1 through a second resistor R2;

the second input pin LIN is connected with a second signal output end PWM _ L of the main control chip U1 through a third resistor R3;

a high side floating supply offset voltage pin VS, a high side output pin HO, a low side output pin LO, and a load driving module 200;

the high-end output pin HO is also connected with the feedback self-locking module 500;

the high-end floating power supply voltage pin VB is connected with the high-end floating power supply offset voltage pin VS through a second capacitor C2;

the power connection pin Com is grounded.

Optionally, the load driving module 200 includes a first switch Q1, a second switch Q2, a fourth resistor R4, a fifth resistor R5, a sixth resistor R6, a seventh resistor R7, an eighth resistor R8, a ninth resistor R9, a tenth resistor R10, a third capacitor C3, a fourth capacitor C4, a fifth capacitor C5, a second diode D2, a third diode D3, a fourth diode D4, and a fifth diode D5;

a first pole pin of the first switch Q1 is connected to the normally open end NO of the start switch U2, a second pole pin of the first switch Q1 is connected to one end of the fourth resistor R4, and a third pole pin of the first switch Q1 is connected to the drive control module 100, the first pole pin of the second switch Q2, and the first end Uj1 of the load U3;

in implementation, the third pin of the first switch Q1 is connected to the high-side floating power offset voltage pin VS;

one end of a fourth resistor R4 is connected to one end of the third capacitor C3, the anode of the second diode D2 and the cathode of the third diode D3, and the other end of the fourth resistor R4 is connected to the driving control module 100;

in implementation, the other end of the fourth resistor R4 is connected to the high-side output pin HO;

the cathode of the second diode D2 is connected to the other end of the fourth resistor R4 through a fifth resistor R5;

the other end of the third capacitor C3 and the anode of the third diode D3 are both connected to the third pin of the first switch Q1;

the sixth resistor R6 is connected with the third capacitor C3 in parallel;

a first end Uj1 of the load U3 is connected with a second end Uj2 of the load U3 through a fourth capacitor C4, and a second end Uj2 of the load U3 is grounded through a seventh resistor R7; in practice, the seventh resistor R7 is a voltage dividing resistor of the load driving module 200;

a second pole pin of the second switch tube Q2 is connected to one end of the eighth resistor R8, one end of the fifth capacitor C5, an anode of the fourth diode D4, and a cathode of the fifth diode D5, and a third pole pin of the second switch tube Q2 is grounded;

the other end of the eighth resistor R8 is connected to the drive control module 100;

in implementation, the other end of the eighth resistor R8 is connected to the low-side output pin LO;

a cathode of the fourth diode D4 is connected to the other end of the eighth resistor R8 through a ninth resistor R9;

the other end of the fifth capacitor C5 and the anode of the fifth diode D5 are connected to the third pin of the second switch Q2;

a tenth resistor R10 is connected in parallel with the fifth capacitor C5.

Optionally, the load detection module 300 includes a third switching tube Q3, an eleventh resistor R11, a twelfth resistor R12, a thirteenth resistor R13, a fourteenth resistor R14, a sixth capacitor C6, a seventh capacitor C7, a sixth diode D6, and a seventh diode D7;

a first pole pin of the third switching tube Q3 is connected to the load driving module 200, a second pole pin of the third switching tube Q3 is connected to one end of an eleventh resistor R11 and one end of a twelfth resistor R12, and a third pole pin of the third switching tube Q3 is connected to one end of a thirteenth resistor R13 and one end of a fourteenth resistor R14;

in implementation, a first pole pin of the third switching tube Q3 is connected to one end of the seventh resistor R7;

the other end of the eleventh resistor R11 is connected with the first voltage end V1;

the other end of the twelfth resistor R12 is grounded;

the other end of the thirteenth resistor R13 is connected with the second voltage end V2;

the other end of the fourteenth resistor R14 is connected to one end of the sixth capacitor C6, the anode of the sixth diode D6, and the anode of the seventh diode D7;

the other end of the sixth capacitor C6 is grounded;

the cathode of the sixth diode D6 is connected to the first voltage terminal V1;

the cathode of the seventh diode D7 is connected to the voltage regulation module 400;

the seventh capacitor C7 is connected in parallel with the twelfth resistor R12.

Optionally, the voltage regulating module 400 includes a fourth switch Q4, a fifteenth resistor R15, a sixteenth resistor R16 and an eighth capacitor C8;

a first pole pin of the fourth switching tube Q4 is connected to the driving control module 100, a second pole pin of the fourth switching tube Q4 is connected to one end of a fifteenth resistor R15 and one end of a sixteenth resistor R16, and a third pole pin of the fourth switching tube Q4 is grounded;

in implementation, a first pole pin of the fourth switching tube Q4 is connected to the first input pin HIN;

the other end of the fifteenth resistor R15 is connected to the load detection module 300 and the feedback self-locking module 500;

in practice, the other end of the fifteenth resistor R15 is connected to the cathode of the seventh diode D7;

the other end of the sixteenth resistor R16 is grounded;

the eighth capacitor C8 is connected in parallel with the sixteenth resistor R16.

Optionally, the feedback self-locking module 500 includes a fifth switch Q5, a sixth switch Q6, a seventeenth resistor R17, an eighteenth resistor R18, a nineteenth resistor R19, a twentieth resistor R20, a twenty-first resistor R21, a ninth capacitor C9, a tenth capacitor C10, an eighth diode D8, a ninth diode D9, and a twelfth diode D10;

a first pole pin of the fifth switch Q5 is connected to the load driving module 200, a second pole pin of the fifth switch Q5 is connected to one end of a seventeenth resistor R17, and a third pole pin of the fifth switch Q5 is connected to one end of an eighteenth resistor R18;

in implementation, the first pole pin of the fifth switch tube Q5 is connected to the high-side output pin HO;

the other end of the seventeenth resistor R17 is connected to the anode of the eighth diode D8, and the cathode of the eighth diode D8 is connected to the normally open end NO of the start switch U2;

the other end of the eighteenth resistor R18 is connected to the second pole pin of the sixth switching tube Q6, one end of the nineteenth resistor R19, and the cathode of the ninth diode D9;

a first pole pin of a sixth switching tube Q6 is connected with the self-locking release module 600, one end of a twentieth resistor R20, one end of a twenty-first resistor R21 and one end of a ninth capacitor C9, and a third pole pin of the sixth switching tube Q6 is grounded;

the other end of the nineteenth resistor R19, the anode of the ninth diode D9 and the other end of the ninth capacitor C9 are grounded;

the other end of the twentieth resistor R20 is connected with the second voltage end V2;

the other end of the twenty-first resistor R21 is connected with the anode of a twelfth diode D10, and the cathode of the twelfth diode D10 is connected with the voltage regulating module 400;

in practice, the cathode of the twelfth diode D10 is connected to the other end of the fifteenth resistor R15;

a tenth capacitor C10 is connected in parallel with the nineteenth resistor R19.

Optionally, the self-locking releasing module 600 includes a seventh switch Q7, a twenty-second resistor R22, a twenty-third resistor R23, a twenty-fourth resistor R24, a twenty-fifth resistor R25, a twenty-sixth resistor R26, a twenty-seventh resistor R27, a twenty-eighth resistor R28, an eleventh capacitor C11, an eleventh diode D11, and a twelfth diode D12;

a first pole pin of the seventh switch Q7 is connected to the feedback self-locking module 500 through a twelfth resistor R22, a second pole pin of the seventh switch Q7 is connected to one end of a twenty-third resistor R23 and one end of a twenty-fourth resistor R24, and a third pole pin of the seventh switch Q7 is grounded;

in implementation, the first pole tube leg of the seventh switch tube Q7 is connected to the first pole tube leg of the sixth switch tube Q6 through the twelfth resistor R22;

the other end of the twenty-third resistor R23 is grounded;

the other end of the twenty-fourth resistor R24 is connected to one end of the twenty-fifth resistor R25, one end of the eleventh capacitor C11 and the anode of the eleventh diode D11;

the other end of the twenty-fifth resistor R25 is connected with one end of a twenty-sixth resistor R26 and the other end of a twenty-seventh resistor R27;

the other end of the eleventh capacitor C11 and the other end of the twenty-sixth resistor R26 are grounded;

the cathode of the eleventh diode D11 is connected to the first voltage terminal V1;

the other end of the twenty-seventh resistor R27 is connected with the cathode of a twelfth diode D12;

an anode of the twelfth diode D12 is connected to one end of the twenty-eighth resistor R28;

the other end of the twenty-eighth resistor R28 is connected to the normally-closed end NC of the start switch U2.

Optionally, as shown in fig. 4, the voltage detection module 700 includes an operational amplifier U5, a twenty-ninth resistor R29, a thirty-third resistor R30, a thirty-first resistor R31, a thirty-second resistor R32, and a twelfth capacitor C12;

a non-inverting input end of the operational amplifier U5 is connected to one end of a twenty-ninth resistor R29 and one end of a twelfth capacitor C12, an inverting input end of the operational amplifier U5 is connected to one end of a thirty-first resistor R30, one end of a thirty-first resistor R31 and the other end of a twelfth capacitor C12, and an output end of the operational amplifier U5 is connected to the other end of the thirty-first resistor R31 and one end of a thirty-second resistor R32;

the other end of the twenty-ninth resistor R29 is connected with one end of the voltage dividing resistor;

the other end of the thirtieth resistor R30 is connected with the other end of the divider resistor;

in implementation, the other end of the twenty-ninth resistor R29 is connected to one end of the seventh resistor R7, and the other end of the thirty-third resistor R30 is connected to the other end of the seventh resistor R7;

the other end of the thirty-second resistor R32 is connected with the main control chip U1.

In implementation, the other end of the thirty-second resistor R32 is connected to the signal input terminal Vin of the main control chip U1.

Optionally, each of the switching tubes may adopt a MOS tube, a triode, or another switching element, which is not limited herein. For example, taking the switching tube as an MOS tube as an example, the first pole pin, the second pole pin, and the third pole pin of the switching tube are respectively a drain, a gate, and a source of the MOS tube. And when the switch tube is a triode, the first electrode pin, the second electrode pin and the third electrode pin of the switch tube are respectively an emitting electrode, a base electrode and a collector electrode of the triode. As shown in fig. 3 and 4, the first switching tube Q1, the second switching tube Q2, the fourth switching tube Q4, the sixth switching tube Q6 and the seventh switching tube Q7 are NMOS transistors, and the third switching tube Q3 and the fifth switching tube Q5 are NPN transistors.

In the working process, when the start switch U2 is pressed, the first signal output terminal PWM _ H and the second signal output terminal PWM _ L of the main control chip U1 output PWM signals to the first input pin HIN and the second input pin LIN of the driving chip U4, wherein the first input pin HIN of the driving chip U4 is at a high level, at this time, the high-end output pin HO of the driving chip U4 outputs a high level to the gate of the first switch tube Q1, the first switch tube Q1 is turned on, and the normally open end NO of the start switch U2 outputs a level to the load U3 so that the load U3 normally works.

When the current of the load driving module 200 is increased due to the abnormal operation of the load U3, a large current flows through the seventh resistor R7, the voltages of the first voltage terminal V1 and the second voltage terminal V2 can be specifically set according to circuit parameters, in some embodiments, taking the example that the first voltage terminal V1 outputs 3.3V and the second voltage terminal V2 outputs 15V, since the voltage of the first pole leg of the third diode Q3 is raised, so that the third diode Q3 is turned off, the voltage of the anode terminal of the sixth diode D6 is pulled up by the second voltage terminal V2 and clamped by the sixth diode D6 at about 3.3V, and the voltage of the cathode terminal of the seventh diode D7 is also about 3.3V, so that the fourth diode Q4 is turned on to pull down the first input pin n of the driving chip U4, the output pin of the high-side output pin of the driving chip hiu 4 is also low, so that the voltage of the fifth diode Q5 is turned off, and the sixth diode Q6 is turned off, the second voltage end V2 charges a ninth capacitor C9 through a twentieth resistor R20, the ninth capacitor C9 feeds back a high level to a second-stage pin of a fourth switch tube Q4 after being charged for a period of time, the fourth switch tube Q4 is maintained to be conducted, the first input pin HIN of the driving chip U4 is pulled down to form positive feedback, and the self-locking function is achieved.

Similarly, when the load U3 works abnormally to increase the current of the load driving module 200, the main control chip U1 detects that the voltage division of the seventh resistor R7 increases, thereby determining that the load U3 is abnormal, at this time, the main control chip U1 actively pulls down the first input pin HIN for a period of time, so that the output of the high-end output pin HO of the driving chip U4 is also low, which causes the fifth switching tube Q5 to be turned off, thereby causing the sixth switching tube Q6 to be turned off, the second voltage end V2 charges the ninth capacitor C9 through the twentieth resistor R20, the ninth capacitor C9 charges for a period of time and then feeds back the high level to the second-stage pin of the fourth switching tube Q4, the fourth switching tube Q4 is maintained to be turned on, and the first input pin HIN of the driving chip U4 is pulled down to form positive feedback, thereby implementing the self-locking function.

When the starting switch U2 is released, the normally-closed end NC of the starting switch U2 outputs a bus voltage to turn on the seventh switch tube Q7, so as to discharge the ninth capacitor C9 to release the self-locking mode, which results in turning off the fourth switch tube Q4, when the starting switch U2 is pressed again, the first input pin HIN of the driving chip U4 is at a high level, so that the high-end output pin HO of the driving chip U4 outputs a high-level driving signal, the driving signal is faster than the time of charging the ninth capacitor C9, so that the load U3 is successfully driven, and at the same time, the fifth switch tube Q5 is turned on, so that the sixth switch tube Q6 is also turned on, and further, the ninth capacitor C9 is discharged without self-locking.

Example four

In a second aspect, the present application further provides a lawn mower comprising the self-locking circuit as described above.

When the self-locking mower is implemented, the main control chip U1 is arranged in the mower, the main control chip U1 can be a single chip microcomputer, the self-locking circuit comprises a driving control module 100, a load driving module 200, a load detection module 300, a voltage regulation module 400, a feedback self-locking module 500 and a self-locking release module 600, wherein the driving control module 100 is connected with the main control chip U1 and receives a driving signal output by the main control chip U1 to output a control signal; the load driving module 200 is connected with the driving control module 100, the normally open end NO of the start switch U2 and the load U3, and receives a control signal to turn on or off the connection between the normally open end NO of the start switch U2 and the load U3; the load detection module 300 is connected to the load driving module 200, and is configured to detect a working state of the load U3 and output a detection signal; the voltage adjusting module 400 is connected to the driving control module 100 and the load detecting module 300, and receives the detection signal to adjust the input voltage of the driving control module 100; the feedback self-locking module 500 is connected with the driving control module 100 and the voltage regulating module 400, receives the control signal output by the control module 100, and outputs a self-locking signal to the voltage regulating module 400 when the control signal meets a preset condition, so that the voltage regulating module 400 is in a target state; the self-locking release module 600 is connected to the normally closed end NC of the start switch U2 and the feedback self-locking module 500, and receives the normally closed signal output by the normally closed end NC to output a release signal to the feedback self-locking module 500, so that the feedback self-locking module 500 stops outputting the self-locking signal.

In practice, the main control chip U1 may output a PWM signal to the driving control module 100 to control the operation of the load U3, and optionally, the load U3 refers to a functional element or a component in the lawn mower, for example, the load U3 includes, but is not limited to, a motor, a resistor, a coil, or the like, and is not limited herein. When receiving the driving signal output by the main control chip U1, the driving control module 100 outputs a corresponding control signal to the load driving module 200 according to the driving signal.

Optionally, the load driving module 200 is connected to the output terminal of the driving control module 100 to receive the control signal output by the driving control module 100, and turns on or off the connection between the normally open terminal NO of the start switch U2 and the load U3 according to the control signal; optionally, the start switch U2 includes a normally open end NO, a normally closed end NC and a common end COM, where the common end COM is connected to the bus voltage VCC, and when the start switch U2 is pressed, the normally open end NO is connected to the common end COM, the start switch U2 is in a normally open state, and the normally open end NO may output the voltage of the bus voltage VCC; when the starting switch U2 is released, the normally closed terminal NC is connected to the common terminal COM, the starting switch U2 is in a normally closed state, and the normally closed terminal NC can output the voltage of the bus voltage VCC.

In operation, when the device presses the start switch U2, the start switch U2 enters a normally open state to output voltage to the load U3 through a normally open end NO to drive the load U3 to operate. The load driving module 200 may turn on the connection between the normally open end NO and the load U3 to operate the load U3, and in other embodiments, the load driving module 200 may turn off the connection between the normally open end NO and the load U3 to stop the load U3.

When the load U3 works abnormally, the load detection module 300 outputs a detection signal indicating that the load U3 works abnormally to the voltage regulation module 400, so that the voltage regulation module 400 sets the input voltage of the driving control module 100 low, and further, the driving control module 100 outputs a low-level control signal for controlling the load U3 to stop working, and cuts off the connection between the normally open end NO and the load U3, so as to control the load U3 to stop working, and simultaneously, the feedback self-locking module 500 detects the control signal output by the driving control module 100 and compares the control signal with a preset electrical signal, wherein the preset electrical signal is a low-level signal, that is, when the feedback self-locking module 500 detects that the control signal output by the driving control module 100 is a low-level signal, a preset condition is satisfied, the feedback self-locking module 500 outputs a self-locking signal to the voltage regulation module 400 to self-lock the voltage regulation module 400 in a target state, optionally, the target state is a state of setting the input voltage of the driving control module 100 to be low, and at this time, even though the main control chip U1 still outputs the PWM signal of high level to the input terminal of the driving control module 100, the input terminal of the driving control module 100 is still set to be low under the action of the voltage adjusting module 400, so that the driving control module 100 continuously outputs the control signal of low level, thereby continuously controlling the load U3 to stop working, and implementing the self-locking function.

The embodiment of the present invention outputs a driving signal to the driving control module 100 through the main control chip U1, so that the driving control module 100 outputs a control signal to the load driving module 200 to turn on or turn off the connection between the normally open end NO of the start switch U2 and the load U3, and simultaneously, the load detection module 300 detects the working state of the load U3 and outputs the working state to the voltage regulation module 400, the voltage regulation module 400 can adjust the voltage at the input end of the driving control module 100, so that the self-locking feedback module 500 outputs a self-locking signal when the control signal output by the driving control module 100 meets the preset condition, so as to self-lock the voltage regulation module 400 at the target state, thereby realizing the self-locking function, and further, the self-locking release module 600 can output a release signal after receiving the normally closed signal, so as to make the feedback self-locking module 500 stop outputting the self-locking signal, thereby waking up the load U3 to work again, therefore, accidents such as load U3 or circuit damage caused by continuous control of the load U3 under the abnormal condition of the load U3 are avoided, and the load U3 and the circuit are protected from being damaged.

The above description is only exemplary of the present invention and should not be construed as limiting the present invention, and any modifications, equivalents and improvements made within the spirit and principles of the present invention are intended to be included within the scope of the present invention.

Claims

1. A self-latching circuit, comprising:

the driving control module is connected with the main control chip and used for receiving the driving signal output by the main control chip so as to output a control signal;

the load driving module is connected with the driving control module, the normally-open end of the starting switch and the load and receives the control signal to switch on or off the connection between the normally-open end of the starting switch and the load;

the voltage adjusting module is connected with the driving control module and the load detection module, and receives the detection signal to adjust the input voltage of the driving control module;

and the self-locking release module is connected with the normally closed end of the starting switch and the feedback self-locking module, receives the normally closed signal output by the normally closed end and outputs a release signal to the feedback self-locking module so as to enable the feedback self-locking module to stop outputting the self-locking signal.

2. The self-locking circuit of claim 1, further comprising:

and the voltage detection module is connected with the main control chip and the load driving module, receives a voltage division signal of a voltage division resistor in the load driving module and outputs the voltage division signal to the main control chip so as to enable the main control chip to stop outputting the driving signal.

3. The self-locking circuit of claim 1, wherein the driving control module comprises a driving chip, a first resistor, a second resistor, a third resistor, a first capacitor, a second capacitor, and a first diode;

the chip voltage pin is grounded through the first capacitor, the chip voltage pin is also connected with the anode of the first diode through the first resistor, and the cathode of the first diode is connected with the high-end floating power supply voltage pin;

the first input pin is connected with a first signal output end of the main control chip through the second resistor;

the second input pin is connected with a second signal output end of the main control chip through the third resistor;

the high-side floating power supply offset voltage pin, the high-side output pin and the low-side output pin and the load driving module;

the high-end floating power supply voltage pin is connected with the high-end floating power supply offset voltage pin through the second capacitor;

the power connection pin is grounded.

4. The self-locking circuit of claim 1, wherein the load driving module comprises a first switch tube, a second switch tube, a fourth resistor, a fifth resistor, a sixth resistor, a seventh resistor, an eighth resistor, a ninth resistor, a tenth resistor, a third capacitor, a fourth capacitor, a fifth capacitor, a second diode, a third diode, a fourth diode, and a fifth diode;

one end of the fourth resistor is connected with one end of the third capacitor, the anode of the second diode and the cathode of the third diode, and the other end of the fourth resistor is connected with the driving control module;

the cathode of the second diode is connected with the other end of the fourth resistor through the fifth resistor;

the sixth resistor is connected with the third capacitor in parallel;

the first end of the load is connected with the second end of the load through the fourth capacitor, and the second end of the load is grounded through the seventh resistor;

a second diode pin of the second switch tube is connected with one end of the eighth resistor, one end of the fifth capacitor, an anode of the fourth diode and a cathode of the fifth diode, and a third diode pin is grounded;

the cathode of the fourth diode is connected with the other end of the eighth resistor through the ninth resistor;

the tenth resistor is connected in parallel with the fifth capacitor.

5. The self-locking circuit of claim 1, wherein the load detection module comprises a third switch tube, an eleventh resistor, a twelfth resistor, a thirteenth resistor, a fourteenth resistor, a sixth capacitor, a seventh capacitor, a sixth diode, and a seventh diode;

the other end of the eleventh resistor is connected with a first voltage end;

the other end of the twelfth resistor is grounded;

the other end of the thirteenth resistor is connected with a second voltage end;

the other end of the sixth capacitor is grounded;

the cathode of the sixth diode is connected with the first voltage end;

the seventh capacitor is connected in parallel with the twelfth resistor.

6. The self-locking circuit of claim 1, wherein the voltage regulation module comprises a fourth switching tube, a fifteenth resistor, a sixteenth resistor, and an eighth capacitor;

a first pole pin of the fourth switch tube is connected with the driving control module, a second pole pin of the fourth switch tube is connected with one end of the fifteenth resistor and one end of the sixteenth resistor, and a third pole pin of the fourth switch tube is grounded;

the other end of the sixteenth resistor is grounded;

the eighth capacitor is connected in parallel with the sixteenth resistor.

7. The self-locking circuit of claim 1, wherein the feedback self-locking module comprises a fifth switch tube, a sixth switch tube, a seventeenth resistor, an eighteenth resistor, a nineteenth resistor, a twentieth resistor, a twenty-first resistor, a ninth capacitor, a tenth capacitor, an eighth diode, a ninth diode, and a twelfth diode;

a first pole pin of the fifth switch tube is connected with the load driving module, a second pole pin of the fifth switch tube is connected with one end of the seventeenth resistor, and a third pole pin of the fifth switch tube is connected with one end of the eighteenth resistor;

the other end of the twentieth resistor is connected with a second voltage end;

the other end of the twenty-first resistor is connected with the anode of the twelfth pole tube, and the cathode of the twelfth pole tube is connected with the voltage regulating module;

the tenth capacitor is connected in parallel with the nineteenth resistor.

8. The self-locking circuit of claim 1, wherein the self-locking release module comprises a seventh switch tube, a twenty-second resistor, a twenty-third resistor, a twenty-fourth resistor, a twenty-fifth resistor, a twenty-sixth resistor, a twenty-seventh resistor, a twenty-eighth resistor, an eleventh capacitor, an eleventh diode, and a twelfth diode;

a first pole tube pin of the seventh switch tube is connected with the feedback self-locking module through the twenty-second resistor, a second pole tube pin is connected with one end of the twenty-third resistor and one end of the twenty-fourth resistor, and a third pole tube pin is grounded;

the other end of the twenty-third resistor is grounded;

the cathode of the eleventh diode is connected with the first voltage end;

an anode of the twelfth diode is connected with one end of the twenty-eighth resistor;

9. The self-locking circuit of claim 2, wherein the voltage detection module comprises an operational amplifier, a twenty-ninth resistor, a thirty-th resistor, a thirty-first resistor, a thirty-second resistor, and a twelfth capacitor;

a non-inverting input end of the operational amplifier is connected with one end of the twenty-ninth resistor and one end of the twelfth capacitor, an inverting input end of the operational amplifier is connected with one end of the thirty-first resistor, one end of the thirty-first resistor and the other end of the twelfth capacitor, and an output end of the operational amplifier is connected with the other end of the thirty-first resistor and one end of the thirty-second resistor;

the other end of the twenty-ninth resistor is connected with one end of the voltage dividing resistor;

the other end of the thirty-second resistor is connected with the main control chip.

10. A lawnmower comprising a self-locking circuit according to any one of claims 1 to 9.