An active seat belt control circuit

Abstract

The application relates to an active safety belt control circuit which comprises a power supply, a controller, a driver, a driving module, a switching module, an operational amplifier collection module and a motor; a voltage output end of the power supply is electrically connected to a power supply end of the controller through a system basic chip, an input and output end of the controller is electrically connected to an input end of the driver, a plurality of output ends of the driver are respectively and correspondingly electrically connected to a plurality of control ends of the driving module, a first output end of the driving module is electrically connected to a positive electrode of the motor, a second output end of the driving module is electrically connected to a negative electrode of the motor, a grounding end of the driving module is sequentially grounded through the switching module, a control end of the switching module is controlled and connected to the controller, two ends of the switching module are respectively electrically connected to a first input end and a second input end of the operational amplifier collection module, and an output end of the operational amplifier collection module is electrically connected to an input end of the controller. The application has the effect of realizing the expected safety belt pretightening force with as few components as possible.

Description

Technical Field

[0001] This application relates to the technical field of seat belt control circuits, and in particular to an active seat belt control circuit. Background Technology

[0002] With the rapid development of the automotive industry, vehicle safety performance has become one of the core areas of industry focus. In modern cars, active seat belts, as an important component of intelligent safety systems, integrate advanced sensor technology to actively tighten before a collision occurs, thereby securing occupants in a safer position and effectively reducing injury from a collision. The introduction of this technology not only improves the overall safety of vehicles but also provides crucial support for the improvement of intelligent driving assistance systems, propelling the automotive industry towards higher levels of safety standards.

[0003] In existing technologies, various methods are typically employed to control the motor-driven seatbelt tightening in order to achieve the functionality of active seatbelts. For example, complex circuit designs are used to control the motor's forward and reverse rotation, or multiple sensors and control modules work together to detect and adjust the tightening force. Additionally, some solutions add extra current sampling circuits to ensure motor stability, while using switching modules to control power supply on / off. While these methods meet the requirements to some extent, they often involve numerous components and complex circuit structures.

[0004] However, a common problem with existing technologies is that the complexity of circuit design and the large number of components can easily lead to increased system costs and reduced reliability. In particular, under unexpected circumstances, problems such as inaccurate motor current sampling or switch control failure may occur, causing abnormal tightening of the seat belt and posing unnecessary safety hazards to drivers and passengers. Utility Model Content

[0005] In order to achieve the desired seat belt pretension with as few components as possible, this application provides an active seat belt control circuit.

[0006] The active seatbelt control circuit provided in this application adopts the following technical solution: An active seatbelt control circuit includes a power supply, a controller, a driver, a drive module, a switch module, an operational amplifier acquisition module, and a motor. The voltage output terminal of the power supply is electrically connected to the power supply terminal of the controller through a system base chip. The input and output terminals of the controller are electrically connected to the input terminal of the driver. Multiple output terminals of the driver are respectively electrically connected to multiple control terminals of the drive module. The first output terminal of the drive module is electrically connected to the positive terminal of the motor, and the second output terminal of the drive module is electrically connected to the negative terminal of the motor. The ground terminal of the drive module is grounded through the switch module. The control terminal of the switch module is controlled and connected to the controller. The two ends of the switch module are respectively electrically connected to the first and second input terminals of the operational amplifier acquisition module, and the output terminal of the operational amplifier acquisition module is electrically connected to the input terminal of the controller.

[0007] By adopting the above technical solution, when the seat belt needs to be tightened, the controller controls the switch module to close, and then the driver controls the drive module to drive the motor to rotate forward or in reverse. By setting the switch module, the drive power can be disconnected when the seat belt does not need to be tightened, avoiding the generation of unexpected tightening force, thereby improving the reliability and safety of the system; by setting the operational amplifier acquisition module, the electrode current can be collected, thereby ensuring the expected effect of the seat belt pretensioning force.

[0008] Preferably, a sampling resistor is also included, the two ends of which are electrically connected to the first input terminal and the second input terminal of the driver, respectively.

[0009] By adopting the above technical solution, accurate sampling of motor current can be achieved, and by comparing the motor current collected by the operational amplifier acquisition module with the motor current collected by the sampling resistor, the accuracy of motor current sampling can be effectively confirmed.

[0010] Preferably, the driving module includes NMOS transistors Q1, Q2, Q3, and Q4. The gates of NMOS transistors Q1, Q2, Q3, and Q4 are electrically connected to multiple output terminals of the driver. The voltage output terminal of the power supply is electrically connected to the drains of NMOS transistors Q1 and Q2. The source of NMOS transistor Q1 is electrically connected to the drain of NMOS transistor Q3, and the source of NMOS transistor Q2 is electrically connected to the drain of NMOS transistor Q4. The sources of NMOS transistors Q3 and Q4 are electrically connected and set as the ground terminal of the driving module. The source of NMOS transistor Q2 is set as the first output terminal of the driving module and electrically connected to the positive terminal of the motor. The source of NMOS transistor Q1 is set as the second output terminal of the driving module and electrically connected to the negative terminal of the motor.

[0011] By adopting the above technical solution, the controller MCU can control the NMOS transistors Q1 and Q3, or NMOS transistors Q2 and Q4, by controlling the driver MOS_Drive, thereby enabling the motor to rotate in both directions and thus tightening the seat belt.

[0012] Preferably, the switching module can be a relay or an NMOS transistor.

[0013] By adopting the above technical solution, it is ensured that the motor only has current flowing through it when the switch module is closed, effectively avoiding seat belt malfunction caused by unexpected current flow.

[0014] Preferably, the system also includes a reverse polarity protection module, through which the voltage output terminal of the power supply is electrically connected to the input terminal of the drive module.

[0015] By adopting the above technical solution, the anti-reverse module can effectively prevent circuit damage or abnormal operation caused by reverse connection of motor power supply wiring, thereby improving the reliability of the circuit.

[0016] Preferably, the system base chip is also used for communication connection with an external CAN bus.

[0017] By adopting the above technical solution, the active seat belt control circuit can receive vehicle status information and other sensor data in real time, thereby more accurately determining whether the seat belt needs to be tightened in advance, and improving the safety protection level of drivers and passengers.

[0018] In summary, this application includes at least one of the following beneficial technical effects: 1. By simplifying circuit design and reducing the number of components, the control and shutdown of the motor drive circuit and the acquisition and comparison of motor current can be realized, thereby reducing system cost and improving reliability; 2. A switching module is used to control the on / off of the drive power supply to prevent the seat belt from tightening abnormally under unexpected circumstances, thus ensuring the safety of the driver and passengers; 3. The motor current is acquired through the operational amplifier acquisition module and the sampling resistor, and the motor current values ​​acquired by the two are compared to confirm the accuracy of the motor current sampling and ensure that the seat belt pretension meets the expected requirements. Attached Figure Description

[0019] Figure 1 This is a circuit diagram of an embodiment of this application.

[0020] Reference numerals: 1. Driver module. Detailed Implementation

[0021] The following is in conjunction with the appendix Figure 1This application will be described in further detail.

[0022] This application discloses an active seat belt control circuit.

[0023] Reference Figure 1 An active seatbelt control circuit includes a power supply (POWER), a controller (MCU), a system base chip (SBC), a driver (MOS_Drive), a drive module 1, a switching module, a sampling resistor (R1), an operational amplifier acquisition module, and a motor for driving the seatbelt. The voltage output terminal of the power supply (POWER) is electrically connected to the power supply terminal of the controller (MCU) through the system base chip (SBC). The input and output terminals of the controller (MCU) are electrically connected to the input terminals of the driver (MOS_Drive), and multiple output terminals of the driver (MOS_Drive) are respectively electrically connected to multiple control terminals of the drive module 1. The voltage output terminal of the power supply (POWER) is also electrically connected to the input terminal of the drive module 1. The drive module 1 has multiple control terminals, each controlled and connected to multiple output terminals of the driver (MOS_Drive). The first output terminal of the drive module 1 is electrically connected to the positive terminal of the motor, and the second output terminal of the drive module 1 is electrically connected to the negative terminal of the motor. The ground terminal of the drive module 1 is grounded sequentially through the switching module and the sampling resistor (R1), and the control terminal of the switching module is controlled and connected to the controller (MCU). The two ends of the switch module are electrically connected to the first and second input terminals of the operational amplifier acquisition module, respectively, and the output terminal of the operational amplifier acquisition module is electrically connected to the input terminal of the controller MCU.

[0024] The drive module 1 includes NMOS transistors Q1, Q2, Q3, and Q4. The gates of NMOS transistors Q1, Q2, Q3, and Q4 are electrically connected to multiple output terminals of the driver MOS_Drive. The voltage output terminal of the power supply POWER is electrically connected to the drains of NMOS transistors Q1 and Q2 through a reverse protection module. The source of NMOS transistor Q1 is electrically connected to the drain of NMOS transistor Q3, and the source of NMOS transistor Q2 is electrically connected to the drain of NMOS transistor Q4. The sources of NMOS transistors Q3 and Q4 are electrically connected and serve as the ground terminal of the drive module 1. The source of NMOS transistor Q2 is set as the first output terminal of the drive module 1 and electrically connected to the positive terminal of the motor. The source of NMOS transistor Q1 is set as the second output terminal of the drive module 1 and electrically connected to the negative terminal of the motor.

[0025] When the seatbelt needs to be controlled, the controller MCU first outputs a shut-off signal to the switching module. Then, the controller MCU controls the driver MOS_Drive to turn on NMOS transistors Q1 and Q3, or NMOS transistors Q2 and Q4, thereby enabling the motor to rotate in both directions and tightening the seatbelt. The anti-reverse module can be set as a relay or an NMOS transistor, effectively preventing reverse power supply to the motor and avoiding circuit damage caused by reverse power connection.

[0026] Specifically, the switching module can be configured as a relay or an NMOS transistor to drive the switching control circuit. Current only flows through the motor when the switching module is closed. A relay typically consists of a coil and contacts; when the coil is energized, the contacts close, and the circuit is completed. An NMOS transistor, on the other hand, achieves its switching function by controlling its gate voltage. Through the control of the switching module, the seatbelt can be disconnected when tightening is not required, thus shutting off the drive power and preventing circuit failure and unexpected tightening force.

[0027] The operational amplifier acquisition module amplifies and acquires the voltage across the switching module, enabling calculation of the first motor current value. The sampling resistor R1 is electrically connected to the first and second input terminals of the driver MOS_Drive, respectively, allowing calculation of the second motor current value. The controller MCU compares the acquired first and second motor current values ​​to verify the accuracy of the motor current sampling, ensuring the tightening force meets expectations.

[0028] The system base chip SBC provides operating voltage to the controller MCU and communicates with the external CAN bus to transmit signals. This enables the active seat belt control circuit to receive vehicle status information and other sensor data in real time, thereby more accurately determining whether the seat belt needs to be tightened in advance and improving the safety protection level of drivers and passengers.

[0029] The implementation principle of an active seatbelt control circuit according to an embodiment of this application is as follows: by simplifying the circuit structure and reducing the number of components, the system cost is reduced. Simultaneously, through precise motor current sampling and comparison, the pretensioning force of the seatbelt is ensured to meet the expected requirements. Furthermore, through reasonable switching control, unexpected tightening forces are avoided, improving system safety.

[0030] The above are all preferred embodiments of this application and are not intended to limit the scope of protection of this application. Therefore, all equivalent changes made in accordance with the structure, shape and principle of this application should be covered within the scope of protection of this application.

Claims

1. An active seatbelt control circuit, characterized in that: The system includes a power supply, a controller, a driver, a drive module (1), a switch module, an operational amplifier acquisition module, and a motor. The voltage output terminal of the power supply is electrically connected to the power supply terminal of the controller through a system base chip. The input and output terminals of the controller are electrically connected to the input terminal of the driver. The multiple output terminals of the driver are respectively electrically connected to the multiple control terminals of the drive module (1). The first output terminal of the drive module (1) is electrically connected to the positive terminal of the motor. The second output terminal of the drive module (1) is electrically connected to the negative terminal of the motor. The ground terminal of the drive module (1) is grounded through the switch module. The control terminal of the switch module is controlled and connected to the controller. The two ends of the switch module are respectively electrically connected to the first and second input terminals of the operational amplifier acquisition module, and the output terminal of the operational amplifier acquisition module is electrically connected to the input terminal of the controller.

2. The active seatbelt control circuit according to claim 1, characterized in that: It also includes a sampling resistor, the two ends of which are electrically connected to the first input terminal and the second input terminal of the driver, respectively.

3. An active seatbelt control circuit according to claim 1 or 2, characterized in that: The driving module (1) includes NMOS transistors Q1, Q2, Q3, and Q4. The gates of NMOS transistors Q1, Q2, Q3, and Q4 are electrically connected to multiple output terminals of the driver. The voltage output terminal of the power supply is electrically connected to the drains of NMOS transistors Q1 and Q2. The source of NMOS transistor Q1 is electrically connected to the drain of NMOS transistor Q3. The source of NMOS transistor Q2 is electrically connected to the drain of NMOS transistor Q4. The sources of NMOS transistors Q3 and Q4 are electrically connected and set as the ground terminal of the driving module (1). The source of NMOS transistor Q2 is set as the first output terminal of the driving module (1) and electrically connected to the positive terminal of the motor. The source of NMOS transistor Q1 is set as the second output terminal of the driving module (1) and electrically connected to the negative terminal of the motor.

4. The active seatbelt control circuit according to claim 1, characterized in that: The switching module can be configured as a relay or an NMOS transistor.

5. The active seatbelt control circuit according to claim 1, characterized in that: It also includes an anti-reverse module, through which the voltage output terminal of the power supply is electrically connected to the input terminal of the drive module (1).

6. The active seatbelt control circuit according to claim 1, characterized in that: The system's base chip is also used for communication with an external CAN bus.

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