Novel standby unlocking system for vehicle door lock

Abstract

The utility model discloses a novel vehicle door lock standby unlocking system which comprises a standby power supply, the standby power supply is connected with a main power supply through a charging switch module and connected with a door lock unit through a discharging switch module, and the main power supply is further connected with the door lock unit. The charging switch module adopts a circuit structure combining a Buck switch controller and an MOSEFT tube, the enabling end of the Buck switch controller is connected with the ignition unit, the grid electrode of the MOSEFT tube is connected with the Buck switch controller, the source electrode of the MOSEFT tube is connected with the main power supply, and the drain electrode of the MOSEFT tube is connected with the standby power supply; the discharge switch module adopts a circuit structure combining an Oring controller and a back-to-back MOSEFT geminate transistor, the enabling end of the Oring controller is connected with the door emergency switch, one end of the MOSEFT geminate transistor is connected with the standby power supply, the other end of the MOSEFT geminate transistor is connected with the door lock unit, the control end of the MOSEFT geminate transistor is connected with the Oring controller, and the door emergency switch is used for generating an unlocking signal.

Description

Technical Field

[0001] This utility model belongs to the technical field of automotive door locks, specifically relating to a novel vehicle door lock backup unlocking system. Background Technology

[0002] Currently, most automobiles still use traditional low-voltage power supply networks, with a single power source powering the load. During driving, if a collision occurs, the entire vehicle may lose power. The door lock control unit may not have enough energy to unlock the doors, leaving them locked and preventing rescuers from opening the doors, thus compromising safety. This phenomenon occurs frequently in reality, and door unlocking after a collision is a crucial certification item in national standard crash tests. To reduce the risk of doors failing to unlock after a collision, a backup power source can be used to power the door lock control unit. When the main power source fails, the backup power source provides power to unlock the doors, allowing for successful rescue of the occupants.

[0003] An existing patent with application number CN115912602A, entitled "A Connection Method for a Backup Power Supply with Single Power Input," discloses that the backup power supply automatically outputs energy to unlock the car door during a collision, such as controlling the backup power supply to output energy when the main power supply fails. However, it does not consider whether the vehicle's condition is suitable for unlocking at this time. For example, if the car door is successfully unlocked during a violent collision that causes the vehicle to roll over, it may open due to accidental touch or system failure, thereby causing further injury or death to the people inside the vehicle. Utility Model Content

[0004] This utility model provides a novel vehicle door lock backup unlocking system, which solves the technical problem that existing technologies output door unlocking signals as long as the load line is disconnected, which can easily lead to accidental activation and further injury or death if the vehicle is in a rollover state.

[0005] This utility model can be achieved through the following technical solutions:

[0006] A novel vehicle door lock backup unlocking system includes a door lock unit and a backup power supply. The backup power supply is connected to the main power supply through a charging switch module and to the door lock unit through a discharging switch module. The main power supply is also connected to the door lock unit.

[0007] The charging switch module adopts a circuit structure combining a PFET Buck switch controller and a MOSEFT transistor. The enable terminal of the PFET Buck switch controller is connected to the ignition unit, the gate of the MOSEFT transistor is connected to the PFET Buck switch controller, its source is connected to the main power supply, and its drain is connected to the backup power supply.

[0008] The discharge switch module adopts a circuit structure combining an Oring controller and a back-to-back MOSEFT pair. The enable terminal of the Oring controller is connected to the door emergency switch, one end of the MOSEFT pair is connected to the backup power supply, the other end is connected to the door lock unit, and the control terminal is connected to the Oring controller. The door emergency switch is used to generate an unlocking signal.

[0009] Furthermore, the drain of the MOSEFT transistor is connected to the backup power supply via an ideal diode, which is used to limit the current flow from the main power supply to the backup power supply.

[0010] Furthermore, the MOSEFT pair includes a pair of back-to-back NMOS transistors, namely a first NMOS transistor and a second NMOS transistor, both of which have body diodes. The source of the first NMOS transistor is connected to the backup power supply, its gate is connected to the Oring controller, and its drain is connected to the drain of the second NMOS transistor. The source of the second NMOS transistor is connected to the door lock unit, and its gate is connected to the Oring controller.

[0011] Furthermore, the main power supply is also connected to the door lock unit through an anti-backflow module, which ensures that current can only flow from the main power supply to the door lock unit and prevents reverse flow.

[0012] Furthermore, the door emergency switch is configured as a push-button switch, which is located on the vehicle door or dashboard.

[0013] The beneficial technical effects of this utility model are as follows:

[0014] When the main power fails and a backup power source is needed, the backup power source can be controlled to supply power to the door lock unit by manually operating the emergency door switch to generate an unlocking signal. This provides a feasible channel for occupants to open the door for self-rescue or for rescue personnel to open the door from the outside to carry out rescue operations. It ensures the safe unlocking of the door in crisis situations and guarantees the smooth implementation of subsequent rescue operations. At the same time, the unlocking signal can be selectively generated by occupants / rescue personnel according to actual needs, rather than being generated at the beginning of the collision, the failure of the main power source, or the disconnection of the load circuit. This reduces the possibility of the door opening during vehicle rollover and causing more serious injuries, making it more practical and applicable to a wider range of situations. Attached Figure Description

[0015] Figure 1 This is a block diagram of the overall circuit structure of this utility model;

[0016] Figure 2 This is a schematic diagram of the circuit structure of the anti-backflow module of this utility model;

[0017] Figure 3This is a schematic diagram of the circuit structure of the charging switch module of this utility model;

[0018] Figure 4 This is a schematic diagram of the circuit structure of the discharge switch module of this utility model. Detailed Implementation

[0019] The specific embodiments of this utility model are described in detail below with reference to the accompanying drawings and preferred embodiments.

[0020] like Figure 1 As shown, this utility model provides a specific embodiment of a novel vehicle door lock backup unlocking system, including an anti-backflow module, a charging switch module, a backup power supply such as an overcapacitor, a door emergency switch, and a discharge switch module. The anti-backflow module is connected in series between the main power supply KL30 and the load Load_KL30 (such as the door lock unit) in the main circuit. The overcapacitor is connected to the output terminal of the anti-backflow module through the charging switch module. The control terminal of the charging switch module is connected to the vehicle's ignition unit, and its output terminal is connected to the backup power supply. The input terminal of the discharge switch module is connected to the backup power supply, its output terminal is connected to the door lock unit, and its control terminal is connected to the door emergency switch. Thus, if the main power supply voltage is normal, the main power supply supplies power to the load through the anti-backflow module. Simultaneously, as long as the vehicle is started, the ignition unit outputs an ignition signal, and the charging switch module closes, allowing the main power supply to charge the overcapacitor. If a collision or other event causes an abnormality in the main power supply, as long as the door emergency switch outputs an unlocking signal, the discharge switch module closes, and the backup power supply such as the overcapacitor can supply power to the load Load_KL30, the door lock unit starts working, and the door can be opened.

[0021] The emergency door switch can be an emergency button switch installed on the door or dashboard, either inside or outside the door. It can be equipped with a protective housing to prevent accidental operation. Passengers or rescue personnel can manually press the emergency door switch at appropriate times to trigger the discharge switch module to close, thereby enabling the backup power supply to power the door lock unit. This prevents the backup power supply from being triggered immediately upon a collision or failure of the main power supply, effectively reducing the possibility of further injury to passengers due to the door being opened at the wrong time.

[0022] Specifically as follows:

[0023] like Figure 2As shown, the reverse current protection module consists of an ideal diode controller chip and an N-channel MOSEFT transistor connected to it. This achieves a forward voltage drop as low as 20mV and ensures unidirectional current flow from the main power supply KL30 to the load Load_KL30, preventing reverse current and thus avoiding the release of overcapacitated energy. Furthermore, when a short circuit occurs in the load Load_KL30, the current in the N-channel MOSEFT transistor must be greater than the fuse's trip current; the reverse current protection module must not be damaged before the fuse trips. The ideal diode controller chip, namely the Oring controller chip LM74700, is connected to the source, drain, and gate of the N-channel MOSEFT transistor. It controls the conduction and turn-off of the N-channel MOSEFT transistor based on the voltage between the source and gate, achieving low-loss reverse protection.

[0024] like Figure 3 As shown, the charging switch module uses a PFET Buck switch controller. The enable terminal EN is connected to the output of the ignition signal KL15 via a diode or an ideal diode, providing reverse polarity protection. After KL15 is powered on, the charging circuit controlled by the PFET Buck switch controller operates in overcapacitance charging mode. Its input terminal VIN is connected to the output of the reverse current protection module. Low-loss reverse protection is achieved through the reverse current protection module's Oring controller and a high-power MOSFET. The PGATE pin of the PFET Buck switch controller is connected to the gate of a MOSFET. The source of the MOSFET and the input terminal VIN of the PFET Buck switch controller are both connected to the output of the reverse current protection module, i.e., connected to the main power supply. Its drain is connected to the backup power supply.

[0025] During charging, the PFET Buck switch controller uses the feedback signal FB to achieve constant on-time control. When the PFET is off, the load current is provided by the inductor and output capacitor. As the output voltage drops, the voltage at the feedback input pin FB also drops. When the voltage drops to a threshold, the PFET immediately turns on. During the PFET's on-time, the inductor current rises, causing the voltage at the feedback input pin FB to rise until it exceeds the feedback comparison threshold, thus achieving the target output voltage Vout. Additionally, an ideal diode is connected in series at the output to ensure that, during a mains power failure, the backup power supply will not output energy to the load Load_KL30 through the charging control module if no unlock signal is received.

[0026] like Figure 4As shown, the discharge switch module uses a combination switch consisting of a pair of back-to-back NMOS transistors and an Oring controller chip. The door emergency switch generates an unlocking signal, and the Oring controller chip controls the switching on and off of the transistors. The Oring controller chip is a switching chip of model LM74720-Q1. The input terminal of the transistors is connected to the output terminal of the backup power supply, and its output terminal is connected to the output terminal of the anti-backflow module, and then connected to the door lock unit to prevent the main circuit from directly charging the backup power supply, which would cause overcurrent or overcapacity damage to the charging circuit.

[0027] Specifically, the discharge switch module includes a pair of back-to-back NMOS transistors, namely a first NMOS transistor and a second NMOS transistor, both of which have body diodes. The source of the first NMOS transistor is connected to the backup power supply, its gate is connected to the GATE pin of the Oring controller, and its drain is connected to the drain of the second NMOS transistor. The source of the second NMOS transistor is connected to the door lock unit, and its gate is connected to the PD pin of the Oring controller. A capacitor C2 and an inductor L1 are connected in parallel between the drains of the first and second NMOS transistors. One pin of the capacitor C2 is connected to the CAP pin of the Oring controller, and one pin of the inductor L1 is connected to the LX pin of the Oring controller. The enable pin of the Oring controller, i.e., the EN pin, is connected to the door emergency switch.

[0028] With the transistor in the on state, a forward voltage drop as low as 17mV can be achieved, reducing energy loss during overcapacitance power supply. When the door emergency switch is not closed (i.e., no unlocking signal is input), the Oring controller controls the back-to-back NMOS combination switch to open, preventing the overcapacitance from outputting energy to the load Load_KL30. If the system is short-circuited or open-circuited, and the main power supply fails and requires backup power to discharge, once the door emergency switch is closed, an unlocking signal is generated. The enable terminal of the Oring controller operates, controlling the back-to-back NMOS combination switch to close, allowing the overcapacitance to immediately discharge to the load Load_KL30, thereby unlocking the door.

[0029] When using the novel vehicle door lock backup unlocking system of this utility model for unlocking control, when the main power supply is working normally, it supplies power to the load Load_KL30, such as the door lock unit, via the anti-backflow module. At this time, the vehicle starts, the ignition unit works and outputs an ignition signal, which acts on the enable terminal of the PFET Buck switch controller of the charging switch module. The PFET Buck switch controller starts working and controls the MOSEFT transistor to close, so the main power supply can charge the backup power supply. At this time, the discharge switch module is in the open state. Once a collision or other event causes the main power supply to fail or the load line to disconnect, and the backup power supply is needed to power the door lock unit, as long as the door emergency switch is closed, an unlocking signal is generated, which can trigger the Oring controller of the discharge switch module to work, control the transistor to close, and thus control the backup power supply to power the door lock unit, unlocking the door.

[0030] While specific embodiments of the present invention have been described above, those skilled in the art should understand that these are merely illustrative examples. Various changes or modifications can be made to these embodiments without departing from the principles and essence of the present invention. Therefore, the scope of protection of the present invention is defined by the appended claims.

Claims

1. A novel vehicle door lock backup unlocking system, characterized in that: It includes a door lock unit and a backup power supply. The backup power supply is connected to the main power supply through a charging switch module and to the door lock unit through a discharging switch module. The main power supply is also connected to the door lock unit. The charging switch module adopts a circuit structure combining a PFET Buck switch controller and a MOSEFT transistor. The enable terminal of the PFET Buck switch controller is connected to the ignition unit, the gate of the MOSEFT transistor is connected to the PFET Buck switch controller, its source is connected to the main power supply, and its drain is connected to the backup power supply. The discharge switch module adopts a circuit structure combining an Oring controller and a back-to-back MOSEFT pair. The enable terminal of the Oring controller is connected to the door emergency switch, one end of the MOSEFT pair is connected to the backup power supply, the other end is connected to the door lock unit, and the control terminal is connected to the Oring controller. The door emergency switch is used to generate an unlocking signal.

2. The novel vehicle door lock backup unlocking system according to claim 1, characterized in that: The drain of the MOSEFT transistor is connected to the backup power supply via an ideal diode, which limits the current flow from the main power supply to the backup power supply.

3. The novel vehicle door lock backup unlocking system according to claim 2, characterized in that: The MOSEFT pair includes a pair of back-to-back NMOS transistors, namely a first NMOS transistor and a second NMOS transistor, both of which have body diodes. The source of the first NMOS transistor is connected to the backup power supply, its gate is connected to the Oring controller, and its drain is connected to the drain of the second NMOS transistor. The source of the second NMOS transistor is connected to the door lock unit, and its gate is connected to the Oring controller.

4. The novel vehicle door lock backup unlocking system according to claim 1, characterized in that: The main power supply is also connected to the door lock unit through an anti-backflow module, which ensures that current can only flow from the main power supply to the door lock unit and prevents reverse flow.

5. The novel vehicle door lock backup unlocking system according to claim 1, characterized in that: The door emergency switch is a push-button switch, which is located on the door or dashboard.

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