Unlocking device for engine hood

Abstract

The utility model provides an engine hood unlocking device, which comprises a voltage stabilizing module, a voltage comparison module and a bridge drive chip, and is characterized in that the voltage stabilizing module is used for converting the voltage of a standby power supply into a logic voltage and outputting the logic voltage to the voltage comparison module; the voltage comparison module provides a reference voltage for the comparator after obtaining a voltage through the reference circuit, outputs a sampling voltage after sampling the voltage of the vehicle-mounted power supply through the sampling circuit and outputs the sampling voltage to the comparator, and the comparator compares the reference voltage with the sampling voltage. When the engine hood is unlocked, a control system of the automobile cannot unlock the engine hood in an existing electric drive control unlocking mode, at the moment, the comparator compares that the reference voltage is larger than the sampling voltage, the comparator outputs an enable signal to the bridge drive chip, and the bridge drive chip can drive the motor to operate according to the enable signal, so that the engine hood of the automobile is unlocked.

Description

Technical Field

[0001] The utility model relates to the technical field of automobiles, and particularly relates to a hood unlocking device. Background Art

[0002] With the development of vehicle electrification and intelligence, the mechanical unlocking function has been removed from the hoods of more and more vehicle models, and a more convenient electric drive control unlocking method is adopted instead. However, this method has the following risks: when the vehicle runs out of power or has a low battery, the hood cannot be unlocked by the electric drive control unlocking method, increasing the risk factor of the vehicle. Summary of the Utility Model

[0003] The purpose of the utility model is to provide a hood unlocking device to solve the problem that when the vehicle runs out of power or has a low battery, the hood cannot be unlocked by the electric drive control unlocking method in the prior art, increasing the risk factor of the vehicle.

[0004] To solve the above technical problems, the utility model provides a hood unlocking device, which includes:

[0005] A voltage regulation module, which is used to connect to a backup power supply and generate a logic voltage after obtaining the voltage of the backup power supply;

[0006] A voltage comparison module, which includes a comparator, a sampling circuit, a driving circuit and a reference circuit; after the reference circuit obtains the logic voltage, it forms a loop to provide a reference voltage to the comparator; after the driving circuit obtains the logic voltage, it enables the sampling circuit to form a loop, so that the sampling circuit samples the voltage of the vehicle-mounted power supply and provides a sampling voltage to the comparator; the comparator outputs an enable signal when the reference voltage is greater than the sampling voltage;

[0007] A bridge drive chip, which receives the enable signal to drive the motor to unlock the hood of the vehicle.

[0008] Optionally, the voltage regulation module includes a voltage regulation circuit, a first power switch tube and a second capacitor. One end of the voltage regulation circuit and the input end of the first power switch tube are commonly connected to the backup power supply, the other end of the voltage regulation circuit is grounded, the output end of the first power switch tube and one end of the second capacitor are commonly connected to the voltage comparison module, and the other end of the second capacitor is grounded;

[0009] The voltage regulation circuit is also connected to the driving end of the first power switch tube, and after the voltage regulation circuit obtains the voltage of the backup power supply, it forms a loop to provide a bias voltage for turning on the first power switch tube.

[0010] Optionally, the voltage stabilizing circuit includes a first resistor, a first capacitor, and a second diode. One end of the first resistor is connected to the input end of the first power switch tube, the other end of the first resistor is grounded through the first capacitor, the other end of the first resistor and the driving end of the first power switch tube are commonly connected to the cathode of the second diode, and the anode of the second diode is grounded.

[0011] Optionally, the second diode is a Zener diode; the first power switch tube is an NPN-type triode or an NMOS transistor.

[0012] Optionally, the voltage stabilization module further includes an anti-reverse connection protection circuit. The forward end of the anti-reverse connection protection circuit is used to connect to the backup power supply, and the reverse end of the anti-reverse connection protection circuit is connected to the first power switch tube and the first resistor of the voltage stabilizing circuit.

[0013] Optionally, the reference circuit includes an eighth resistor and a third diode. The third diode is a Zener diode. One end of the eighth resistor is connected to the voltage stabilization module, the other end of the eighth resistor is connected to the cathode of the third diode, the cathode of the third diode is connected to the positive input terminal of the comparator, and the anode of the third diode is grounded.

[0014] Optionally, the sampling circuit includes a third power switch tube, a sixth resistor, and a seventh resistor. The input end of the third power switch tube is used to connect to the vehicle power supply. The output end of the third power switch tube is grounded through the serially connected sixth resistor and seventh resistor. A line is led out between the sixth resistor and the seventh resistor and connected to the negative input terminal of the comparator. The driving end of the third power switch tube is connected to the driving circuit.

[0015] Optionally, the driving circuit includes a second resistor, a third resistor, a fourth resistor, a fifth resistor, and a second power switch tube; the fourth resistor is connected to the voltage stabilization module. The fourth resistor is grounded through the fifth resistor. A line is led out between the fourth resistor and the fifth resistor and connected to the driving end of the second power switch tube. The input end of the second power switch tube is connected to the vehicle power supply through the serially connected second resistor and third resistor. The output end of the second power switch tube is grounded. A line is led out between the second resistor and the third resistor and connected to the driving end of the third power switch tube.

[0016] Optionally, the second power switch tube is an NPN-type triode, and the third power switch tube is a PNP-type triode.

[0017] Optionally, the second power switch tube is an NMOS transistor, and the third power switch tube is a PMOS transistor.

[0018] Optionally, the unlocking device further includes a power supply circuit, which is configured to transmit the voltage of the backup power supply, the logic voltage, and the voltage of the vehicle power supply to the bridge drive chip.

[0019] Optionally, the power supply circuit includes a sixth diode, a seventh diode, an eighth diode, and a ninth diode; the anode terminal of the sixth diode obtains the logic voltage, and the cathode terminal of the sixth diode is connected to the bridge drive chip; the anode terminal of the seventh diode is used to connect to the vehicle power supply, and the cathode terminal of the seventh diode is connected to the bridge drive chip; the anode terminal of the eighth diode is connected to the backup power supply, and the cathode terminal of the eighth diode is connected to the bridge drive chip; the anode terminal of the ninth diode is connected to the vehicle power supply, and the cathode terminal of the ninth diode is connected to the bridge drive chip.

[0020] In summary, in the hood unlocking device provided by the present invention, the device includes a voltage regulation module, a voltage comparison module, and a bridge drive chip. The voltage regulation module converts the voltage of the backup power supply into a logic voltage and outputs it to the voltage comparison module. The voltage comparison module obtains a voltage through a reference circuit and provides a reference voltage to the comparator, and samples the voltage of the vehicle power supply through a sampling circuit and outputs a sampling voltage, and outputs it to the comparator. The comparator compares the reference voltage and the sampling voltage. When the vehicle power supply of the car runs out of power or has insufficient power, the control system of the car cannot unlock the hood through the existing electric drive control unlocking method. At this time, the comparator compares that the reference voltage is greater than the sampling voltage, and the comparator outputs an enable signal to the bridge drive chip. The bridge drive chip can drive the motor to operate according to this enable signal, so as to unlock the hood of the car. In this way, the present invention can solve the problem that the hood cannot be unlocked by the electric drive control unlocking method when the whole vehicle runs out of power or has insufficient power in the prior art, and improves the safety factor of the car. Description of the Drawings

[0021] Those of ordinary skill in the art should understand that the provided drawings are used to better understand the present invention and do not constitute any limitation to the scope of the present invention. Among them:

[0022] Figure 1 is a schematic diagram of the hood unlocking device according to an embodiment of the present invention;

[0023] Figure 2 is a schematic diagram of the voltage regulation module according to an embodiment of the present invention;

[0024] Figure 3 is a schematic diagram of the voltage comparison module according to an embodiment of the present invention;

[0025] Figure 4Schematic diagram of a power supply circuit and a bridge drive chip according to an embodiment of the present invention.

[0026] In the attached drawings:

[0027] 10 - Backup power supply; 20 - Vehicle-mounted power supply; 30 - Voltage regulator module; 31 - Voltage regulation circuit; 41 - Drive circuit; 42 - Sampling circuit; 43 - Reference circuit; U - Comparator; 50 - Bridge drive chip; 60 - Motor; 70 - Power supply circuit;

[0028] Q1 - First power switch; Q2 - Second power switch; Q3 - Third power switch;

[0029] C1 - First capacitor; C2 - Second capacitor;

[0030] D1 - First diode; D2 - Second diode; D3 - Third diode; D4 - Fourth diode; D5 - Fifth diode; D6 - Sixth diode; D7 - Seventh diode; D8 - Eighth diode; D9 - Ninth diode;

[0031] R1 - First resistor; R2 - Second resistor; R3 - Third resistor; R4 - Fourth resistor; R5 - Fifth resistor; R6 - Sixth resistor; R7 - Seventh resistor; R8 - Eighth resistor; R9 - Ninth resistor. Detailed implementation manners

[0032] To make the objectives, advantages, and features of the present invention clearer, the present invention will be further described in detail below with reference to the attached drawings and specific embodiments. It should be noted that the attached drawings are in very simplified forms and not drawn to scale, and are only used to conveniently and clearly assist in explaining the objectives of the embodiments of the present invention. In addition, the structures shown in the attached drawings are often part of the actual structures. In particular, the attached drawings need to show different focuses and sometimes use different scales.

[0033] As used in the present utility model, the singular forms "a", "an" and "the" include plural referents, the term "or" is generally used in the sense of including "and / or", the term "several" is generally used in the sense of including "at least one", the term "at least two" is generally used in the sense of including "two or more", in addition, the terms "first", "second", "third" are only used for descriptive purposes and cannot be construed as indicating or implying relative importance or implicitly indicating the quantity of the indicated technical features. Thus, the features defined with "first", "second", "third" may explicitly or implicitly include one or at least two of such features, "one end" and "the other end" as well as "proximal end" and "distal end" generally refer to two corresponding parts, which include not only the endpoints, the terms "mounted", "connected", "coupled" shall be understood in a broad sense, for example, it may be a fixed connection, a detachable connection, or integrated; it may be a mechanical connection, an electrical connection; it may be directly connected, or indirectly connected through an intermediate medium, it may be the communication inside two elements or the interaction relationship between two elements. In addition, as used in the present utility model, one element being disposed on another element generally only means that there is a connection, coupling, cooperation or transmission relationship between the two elements, and the two elements may be directly or indirectly connected, coupled, cooperated or transmitted through an intermediate element, and cannot be construed as indicating or implying the spatial position relationship between the two elements, that is, one element may be inside, outside, above, below or on one side of another element in any orientation, unless the content clearly indicates otherwise. For those of ordinary skill in the art, the specific meanings of the above terms in the present utility model can be understood according to specific circumstances.

[0034] Figure 1 is a schematic diagram of the hood unlocking device according to an embodiment of the present utility model. Refer to Figure 1, the hood unlocking device of this embodiment includes a voltage stabilizing module 30, a voltage comparison module connected to the voltage stabilizing module 30, and a bridge drive chip 50 connected to the voltage comparison module. The voltage comparison module includes a comparator U, a sampling circuit 42, a driving circuit 41, and a reference circuit 43. The sampling circuit 42 is connected to the inverting input terminal of the comparator U, the reference circuit 43 is connected to the non-inverting input terminal of the comparator U, the driving circuit 41 is connected to the sampling circuit 42, and the sampling circuit 42 is also connected to the vehicle power supply 20 (i.e., the car battery). The bridge drive chip 50 is connected to the output terminal of the comparator U. In one embodiment, the comparator U is connected to the bridge drive chip 50 through a fifth diode D5. Specifically, the anode terminal of the fifth diode D5 is connected to the output terminal of the comparator U, and the cathode terminal of the fifth diode D5 is connected to the bridge drive chip 50. The voltage stabilizing module 30 is connected to the backup power supply 10 of the car. After obtaining the voltage of the backup power supply 10, a logic voltage V1 is generated and output to the voltage comparison module, specifically output to the driving circuit 41 and the reference circuit 43. After obtaining the logic voltage V1, the reference circuit 43 forms a loop, thereby outputting a reference voltage to the non-inverting input terminal of the comparator U. After obtaining the logic voltage V1, the driving circuit 41 enables the sampling circuit 42 to form a loop, and the sampling circuit 42 forming the loop can sample the voltage of the vehicle power supply 20 and obtain a sampling voltage, and output the sampling voltage to the inverting input terminal of the comparator U. The comparator U compares the magnitudes of the reference voltage and the sampling voltage, and outputs an enabling signal to the bridge drive chip 50 when the reference voltage is greater than the sampling voltage. The bridge drive chip 50 is connected to the motor 60. The bridge drive chip 50 receives the enabling signal to drive the motor 60 to unlock the car's hood. Specifically, the bridge drive chip 50 can generate three-phase alternating current through a bridge structure to drive the motor 60 to operate. Further, the comparator U is also connected to the backup power supply 10 or the logic voltage V1, and the comparator U is powered by the backup power supply 10 or the logic voltage V1.

[0035] Thus, for the hood unlocking device of the vehicle in this embodiment, the voltage stabilizing module 30 converts the voltage of the backup power supply 10 into a logic voltage V1 and outputs it to the voltage comparison module. After obtaining the voltage through the reference circuit 43, the voltage comparison module provides a reference voltage to the comparator U, and after sampling the voltage of the vehicle-mounted power supply 20 through the sampling circuit 42, it outputs a sampled voltage and outputs it to the comparator U. The comparator U compares the reference voltage and the sampled voltage. When the vehicle-mounted power supply 20 of the vehicle runs out of power or has insufficient power, the vehicle control system cannot unlock the hood through the existing electric drive control unlocking method. At this time, the comparator U compares and finds that the reference voltage is greater than the sampled voltage, and the comparator U outputs an enabling signal to the bridge drive chip. The bridge drive chip 50 can drive the motor 60 to operate according to this enabling signal, thereby unlocking the hood of the vehicle. Thus, the utility model can solve the problem in the prior art that the hood cannot be unlocked through the electric drive control unlocking method when the whole vehicle runs out of power or has insufficient power, and improves the safety factor of the vehicle.

[0036] Figure 2 It is a schematic diagram of the voltage stabilizing module 30 according to an embodiment of the utility model. Refer to Figure 2 , the voltage stabilizing module 30 includes a voltage stabilizing circuit 31, a first power switch Q1, and a second capacitor C2. One end of the voltage stabilizing circuit 31 and the input end of the first power switch Q1 are commonly connected to the backup power supply 10, and the other end of the voltage stabilizing circuit 31 is grounded. Actually, specifically, one end of the voltage stabilizing circuit 31 and the input end of the first power switch Q1 are commonly connected to the positive pole of the backup power supply 10, and the other end of the regulated voltage is connected to the negative pole of the backup power supply 10. The output end of the first power switch Q1 and one end of the second capacitor C2 are commonly connected to the drive circuit 41 and the reference circuit 43 of the voltage comparison module, and the other end of the second capacitor C2 is grounded; the voltage stabilizing circuit 31 is also connected to the drive end of the first power switch Q1, and after the voltage stabilizing circuit 31 obtains the voltage of the backup power supply 10, a loop is formed to provide a bias voltage for turning on the first power switch Q1.

[0037] Further, the voltage stabilizing circuit 31 includes a first resistor R1, a first capacitor C1, and a second diode D2. One end of the first resistor R1 is connected to the input end of the first power switch Q1, the other end of the first resistor R1 is grounded through the first capacitor C1, and the other end of the first resistor R1 and the drive end of the first power switch Q1 are commonly connected to the cathode of the second diode D2, and the anode of the second diode D2 is grounded. Thus, it can be seen that the first capacitor C1 filters the voltage signal input by the backup power supply 10.

[0038] In one embodiment, the second diode D2 is a Zener diode. After the voltage stabilizing circuit 31 obtains the voltage of the standby power supply 10, the second diode D2 is broken down, and a bias voltage for turning on the first power switch Q1 is provided between the first resistor R1 and the second diode D2. This bias voltage is equal to the breakdown voltage of the second diode D2 itself. The first power switch Q1 is an NPN transistor. The input terminal of the first power switch Q1 is the collector, the output terminal of the first power switch Q1 is the emitter, and the drive terminal of the first power switch Q1 is the base. The first power switch Q1 can also be an NMOS transistor. The input terminal of the first power switch Q1 is the drain, the output terminal of the first power switch Q1 is the source, and the drive terminal of the first power switch Q1 is the gate. In this way, the voltage stabilizing circuit 31 provides a high-level signal for turning on the first power switch Q1 between the first resistor R1 and the second diode D2.

[0039] Preferably, continuing to refer to Figure 2 , the voltage stabilizing module 30 further includes an anti-reverse connection protection circuit. The positive terminal of the anti-reverse connection protection circuit is connected to the standby power supply 10, and the negative terminal of the anti-reverse connection protection circuit is connected to the input terminal of the first power switch Q1 and the first resistor R1. In this way, when the positive terminal of the anti-reverse connection protection circuit is connected and the positive terminal of the standby power supply 10 is connected, a path is presented between the standby power supply 10 and the voltage stabilizing module 30 to transfer the voltage normally; when the positive terminal of the anti-reverse connection protection circuit is connected to the negative terminal of the standby power supply 10, the anti-reverse connection protection circuit is turned off, and an open circuit is presented between the standby power supply 10 and the voltage stabilizing module 30 for anti-reverse connection protection. In one embodiment, the anti-reverse connection protection circuit includes a first diode D1. The anode terminal of the first diode D1 is connected to the standby power supply 10, and the cathode terminal of the first diode D1 is connected to the first resistor R1 and the first power switch Q1. Further, the voltage output after the standby power supply 10 passes through the anti-reverse connection protection circuit is V2, and the comparator U is powered by V2.

[0040] Figure 3 is a schematic diagram of the voltage comparison module according to an embodiment of the present invention. Referring to Figure 3 , the reference circuit 43 includes an eighth resistor R8 and a third diode D3. The third diode D3 is a Zener diode. One end of the eighth resistor R8 is connected to the voltage stabilizing module 30, the other end of the eighth resistor R8 is connected to the cathode terminal of the third diode D3, the cathode terminal of the third diode D3 is connected to the positive-phase input terminal of the comparator U, and the anode terminal of the third diode D3 is grounded. In this way, after the reference circuit 43 obtains the logic voltage V1, the third diode D3 is broken down, and the reference voltage provided to the comparator U is the breakdown voltage of the third diode D3 itself. It can be understood that different third diodes D3 with different breakdown voltages can be selected to adjust the value of the reference voltage.

[0041] Continuing to refer to Figure 3, the sampling circuit 42 includes a third power switch Q3, a sixth resistor R6, and a seventh resistor R7. The input terminal of the third power switch Q3 is used to connect to the vehicle power supply 20. The output terminal of the third power switch Q3 is grounded through the series-connected sixth resistor R6 and seventh resistor R7. For example Figure 3 In Figure 3 , after the sixth resistor R6 and the seventh resistor R7 are connected in series, the seventh resistor R7 is grounded. A line is drawn between the sixth resistor R6 and the seventh resistor R7 and connected to the inverting input terminal of the comparator U. The driving terminal of the third power switch Q3 is connected to the driving circuit 41. In this way, after the driving circuit 41 obtains the logic voltage V1, the third power switch Q3 is turned on, and the sampling circuit 42 forms a closed loop. The sixth resistor R6 and the seventh resistor R7 divide the voltage of the vehicle power supply 20, thereby realizing the sampling of the vehicle power supply 20. The obtained sampling voltage is the voltage on the grounded seventh resistor R7. It can be understood that different values of the sixth resistor R6 and the seventh resistor R7 can be selected to adjust the sampling ratio of the sampling circuit 42 to the voltage of the vehicle power supply 20.

[0042] It should be noted that for the selection of the third diode D3, the sixth resistor R6, and the seventh resistor R7, it should be ensured that the sampling voltage is greater than or equal to the reference voltage when the vehicle is not power-deficient, to avoid abnormal unlocking of the engine hood.

[0043] Further, continue to refer to Figure 3 , the driving circuit 41 includes a second resistor R2, a third resistor R3, a fourth resistor R4, a fifth resistor R5, and a second power switch Q2; the fourth resistor R4 is connected to the voltage regulator module 30. The fourth resistor R4 is grounded through the fifth resistor R5. A line is drawn between the fourth resistor R4 and the fifth resistor R5 and connected to the driving terminal of the second power switch Q2. The input terminal of the second power switch Q2 is connected to the vehicle power supply 20 through the series-connected second resistor R2 and third resistor R3. The output terminal of the second power switch Q2 is grounded. A line is drawn between the second resistor R2 and the third resistor R3 and connected to the driving terminal of the third power switch Q3. In this way, after the driving circuit 41 accesses the logic voltage V1, a bias voltage for turning on the second power switch Q2 is provided between the fourth resistor R4 and the fifth resistor R5. After the second power switch Q2 is turned on, a bias voltage for turning on the third power switch Q3 is provided between the second resistor R2 and the third resistor R3, so that after the third power switch Q3 is turned on, the sampling circuit 42 forms a closed loop to realize the voltage sampling of the vehicle power supply 20.

[0044] In one embodiment, the second power switch Q2 is an NPN bipolar junction transistor. The input terminal of the second power switch Q2 is the collector, the output terminal is the emitter, and the drive terminal is the base. The third power switch Q3 is a PNP bipolar junction transistor. The input terminal of the third power switch Q3 is the emitter, the output terminal is the collector, and the drive terminal is the base. In another embodiment, the second power switch Q2 is an NMOS transistor. The input terminal of the second power switch Q2 is the drain, the output terminal is the source, and the drive terminal is the gate. The third power switch Q3 is a PMOS transistor. The input terminal of the third power switch Q3 is the source, the output terminal is the drain, and the drive terminal is the gate. In this way, a high-level signal is provided between the fourth resistor R4 and the fifth resistor R5 to turn on the second power switch Q2, and a low-level signal is provided between the second resistor R2 and the third resistor R3 to turn on the third power switch Q3.

[0045] Further, referring to Figure 1 , the hood unlocking device further includes a power supply circuit 70. The power supply circuit 70 is provided between the bridge drive chip 50 and the backup power supply 10, between the bridge drive chip 50 and the voltage regulator module 30, and between the bridge drive chip 50 and the vehicle power supply 20. Thus, the voltage of the backup power supply 10, the logic voltage V1, and the voltage of the vehicle power supply 20 are transmitted to the bridge drive chip 50 through the power supply circuit 70 to supply power to the bridge drive chip 50. In this way, when the vehicle runs out of power or has a low battery (i.e., the reference voltage is greater than the sampled voltage), the bridge drive chip 50 can be powered by the backup power supply 10 or the generated logic voltage V1. When the battery of the vehicle has sufficient power (i.e., the reference voltage is less than or equal to the sampled voltage), the bridge drive chip 50 can be powered by the vehicle power supply 20, ensuring that the bridge drive chip 50 can always operate.

[0046] Figure 4 is a schematic diagram of the power supply circuit 70 and the bridge drive chip 50 according to an embodiment of the present invention. In one embodiment, referring to Figure 4 , the power supply circuit 70 includes a sixth diode D6, a seventh diode D7, an eighth diode D8, and a ninth diode D9. The anode terminal of the sixth diode D6 obtains the logic voltage V1, and the cathode terminal of the sixth diode D6 is connected to the bridge drive chip 50. The anode terminal of the seventh diode D7 is used to connect to the vehicle power supply 20, and the cathode terminal of the seventh diode D7 is connected to the bridge drive chip 50. The anode terminal of the eighth diode D8 is connected to the backup power supply 10, and the cathode terminal of the eighth diode D8 is connected to the bridge drive chip 50. The anode terminal of the ninth diode D9 is connected to the vehicle power supply 20, and the cathode terminal of the ninth diode D9 is connected to the bridge drive chip 50.

[0047] Further, referring toFigure 4 , the hood unlocking device of this embodiment further includes a fourth diode D4 and a ninth resistor R9. The anode terminal of the fourth diode D4 is connected to the control system of the vehicle. The cathode terminal of the fourth diode D4 is grounded through the ninth resistor R9, and the cathode terminal of the fourth diode D4 is also connected to the bridge drive circuit. In this way, when the battery power of the vehicle is sufficient, the control signal (MCU_MOTOR_REL) of the control system can be output to the bridge drive chip 50 through the fourth diode D4 to control the bridge drive chip 50 to unlock the hood, realizing the active unlocking of the vehicle hood.

[0048] Although the present utility model is disclosed above in preferred embodiments, the above embodiments are not intended to limit the present utility model. For any person skilled in the art, without departing from the scope of the technical solution of the present utility model, many possible changes and modifications can be made to the technical solution of the present utility model by using the technical content disclosed above, or modified into equivalent embodiments with equivalent changes. Therefore, any simple modification, equivalent change and modification made to the above embodiments based on the technical essence of the present utility model without departing from the content of the technical solution of the present utility model still belong to the scope of protection of the technical solution of the present utility model.

Claims

1. An engine hood unlocking device, characterized in that, Comprising: A voltage regulation module for connecting to a backup power supply and generating a logic voltage after obtaining the voltage of the backup power supply; A voltage comparison module, which includes a comparator, a sampling circuit, a driving circuit, and a reference circuit; After obtaining the logic voltage, the reference circuit forms a loop to provide a reference voltage to the comparator; after obtaining the logic voltage, the driving circuit causes the sampling circuit to form a loop, so that the sampling circuit samples the voltage of the vehicle power supply and provides a sampling voltage to the comparator; the comparator outputs an enable signal when the reference voltage is greater than the sampling voltage; A bridge drive chip, which is used to drive the motor to unlock the hood of the car after receiving the enable signal.

2. The hood unlocking device according to claim 1, wherein The voltage regulation module includes a voltage regulation circuit, a first power switch tube, and a second capacitor. One end of the voltage regulation circuit and the input end of the first power switch tube are commonly connected to the backup power supply. The other end of the voltage regulation circuit is grounded. The output end of the first power switch tube and one end of the second capacitor are commonly connected to the voltage comparison module, and the other end of the second capacitor is grounded; The voltage regulation circuit is also connected to the driving end of the first power switch tube, and after obtaining the voltage of the backup power supply, the voltage regulation circuit forms a loop to provide a bias voltage for turning on the first power switch tube.

3. The hood unlocking device according to claim 2, characterized in that, The voltage regulation circuit includes a first resistor, a first capacitor, and a second diode. One end of the first resistor is connected to the input end of the first power switch tube. The other end of the first resistor is grounded through the first capacitor. The other end of the first resistor and the driving end of the first power switch tube are commonly connected to the cathode of the second diode, and the anode of the second diode is grounded; The second diode is a Zener diode; the first power switch tube is an NPN-type triode or an NMOS tube.

4. The hood unlocking device according to claim 2, characterized in that, The voltage regulation module further includes an anti-reverse connection protection circuit. The forward end of the anti-reverse connection protection circuit is used to connect to the backup power supply, and the reverse end of the anti-reverse connection protection circuit is connected to the first power switch tube and the voltage regulation circuit.

5. The hood unlocking device according to claim 1, wherein, The reference circuit includes an eighth resistor and a third diode. The third diode is a Zener diode. One end of the eighth resistor is connected to the voltage regulation module. The other end of the eighth resistor is connected to the cathode of the third diode. The cathode of the third diode is connected to the positive input terminal of the comparator, and the anode of the third diode is grounded.

6. The hood unlocking device according to claim 1, characterized in that, The sampling circuit includes a third power switch tube, a sixth resistor, and a seventh resistor. The input end of the third power switch tube is used to connect to the vehicle power supply. The output end of the third power switch tube is grounded through the series-connected sixth resistor and seventh resistor. A line is led out between the sixth resistor and the seventh resistor and connected to the negative input terminal of the comparator. The driving end of the third power switch tube is connected to the driving circuit.

7. The hood unlocking device according to claim 6, characterized in that, The driving circuit includes a second resistor, a third resistor, a fourth resistor, a fifth resistor, and a second power switch; the fourth resistor is connected to the voltage regulation module, the fourth resistor is grounded through the fifth resistor, a line is led out between the fourth resistor and the fifth resistor and connected to the driving end of the second power switch, the input end of the second power switch is connected to the vehicle power supply through the series-connected second resistor and third resistor, the output end of the second power switch is grounded, and a line is led out between the second resistor and the third resistor and connected to the driving end of the third power switch.

8. The hood unlocking device according to claim 7, wherein, The second power switch is an NPN-type triode, and the third power switch is a PNP-type triode; Alternatively, the second power switch is an NMOS transistor, and the third power switch is a PMOS transistor.

9. The hood unlocking device according to claim 1, characterized in that, The hood unlocking device further includes a power supply circuit, and the power supply circuit is configured to transmit the voltage of the backup power supply, the logic voltage, and the voltage of the vehicle power supply to the bridge driving chip.

10. The hood unlocking device according to claim 9, characterized in that, The power supply circuit includes a sixth diode, a seventh diode, an eighth diode, and a ninth diode; the anode terminal of the sixth diode obtains the logic voltage, and the cathode terminal of the sixth diode is connected to the bridge driving chip; the anode terminal of the seventh diode is used to connect to the vehicle power supply, and the cathode terminal of the seventh diode is connected to the bridge driving chip; the anode terminal of the eighth diode is connected to the backup power supply, and the cathode terminal of the eighth diode is connected to the bridge driving chip; the anode terminal of the ninth diode is connected to the vehicle power supply, and the cathode terminal of the ninth diode is connected to the bridge driving chip.

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