Drive control device for a wiper motor and vehicle wiper system comprising the device

Abstract

The utility model relates to a kind of drive control device for wiper motor, and vehicle wiper system comprising the drive control device.The drive control device includes half bridge circuit power supply, and: power switch;First drive chip;Second drive chip;Controller;And monitoring unit, wherein, the second drive chip is configured to control the power switch to keep on state when receiving any one of control signal and fail-safe signal, the first drive chip is configured to drive wiper motor forward rotation or reverse rotation based on the control signal when controller is in normal state, and drive wiper motor into safety protection state based on the fail-safe signal when controller is in fault state.The drive control device and vehicle wiper system of the utility model can realize intelligent control and fault safety protection to wiper motor, improve the reliability and functional safety level of system, meet the requirement of modern vehicle to high safety and high reliability.

Description

Technical Field

[0001] This utility model relates to the field of windshield wiper control, and more specifically, to a drive control device for a windshield wiper motor, including a vehicle windshield wiper system using the drive control device. Background Technology

[0002] In traditional vehicle wiper control systems, the wiper motor is typically powered by an electronic control unit (ECU) driving a relay. This approach uses the mechanical switch of the relay to control the on / off state of the motor's power supply, resulting in a simple structure and low cost. However, with the continuous evolution of vehicle electronic and electrical architecture (EEA), especially the increasing demands for functional safety, the limitations of traditional relay solutions in terms of intelligence, controllability, and fault diagnosis capabilities have become increasingly apparent.

[0003] The main problem with existing relay control schemes is that their mechanical structure results in low diagnostic coverage, making it impossible to achieve real-time monitoring of key parameters such as voltage and current, and difficult to respond quickly or safely shut down when a fault occurs. Furthermore, relays suffer from mechanical wear, limited lifespan, and poor vibration resistance, making them prone to becoming single points of failure in the system and affecting overall reliability. Utility Model Content

[0004] To address the problems of low diagnostic coverage, inability to achieve real-time monitoring and rapid protection, and insufficient functional safety level in traditional wiper control systems using relay solutions, this invention proposes an intelligent wiper drive and control scheme based on electronic switches. This drive and control device replaces traditional relays with electronic switches to achieve intelligent control and fault safety protection of the wiper motor, thereby improving the system's reliability and functional safety level.

[0005] The first aspect of this utility model provides a drive control device for a windshield wiper motor, the drive control device including a half-bridge circuit connected to the windshield wiper motor and a power supply for supplying power to the half-bridge circuit, the drive control device further including:

[0006] A power switch is disposed between the power source and the half-bridge circuit, and is used to connect or disconnect the power supply path from the power source to the half-bridge circuit.

[0007] The first driving chip is connected to the control terminal of the half-bridge circuit and is used to drive the half-bridge circuit to make the wiper motor rotate forward or reverse.

[0008] The second driver chip is connected to the control terminal of the power switch and is used to drive the power switch to perform on / off operations.

[0009] A controller, connected to the first and second driver chips to send corresponding control signals to the first and second driver chips respectively; and

[0010] A monitoring unit is configured to monitor the operating status of the controller in real time, and to output a fault safety signal to the first and second driver chips when the controller is detected to be in a fault state.

[0011] The second driving chip is configured to keep the power switch on when it receives either the control signal or the fault safety signal. The first driving chip is configured to drive the wiper motor to rotate forward or reverse based on the control signal when the controller is in a normal state, and to drive the wiper motor to enter a safety protection state based on the fault safety signal when the controller is in a fault state.

[0012] According to an optional embodiment, the monitoring unit is a watchdog timer configured to trigger a reset operation of the controller when a fault is detected in the controller.

[0013] According to an optional embodiment, the controller is further configured to monitor the operating status of the wiper motor in real time, and send an emergency braking signal to the first drive chip when a wiper motor failure is detected, so as to stop the wiper motor from operating.

[0014] According to an optional embodiment, the drive control device further includes a power supply unit and an enable switch for connecting the power supply unit to the second drive chip, the control terminal of which is connected to the controller.

[0015] According to an optional embodiment, the controller is further configured to monitor the operating status of the wiper motor in real time, and to cut off the enable switch when a wiper motor failure is detected, so that the second drive chip turns off the power switch.

[0016] According to an optional embodiment, the half-bridge circuit consists of a high-side switch and a low-side switch, the control terminals of which are connected to the first driver chip.

[0017] A second aspect of this utility model also provides a vehicle windshield wiper system, the vehicle windshield wiper system comprising:

[0018] Wiper motor; and

[0019] The drive control device described above is connected to the wiper motor to control its operation.

[0020] The wiper motor drive control device of this utility model adopts an electronic switch instead of a traditional relay, and combines half-bridge drive, dual-drive chip control, fault-safe signal mechanism and watchdog monitoring technologies to achieve precise control and real-time fault diagnosis of the wiper motor power supply path, significantly improving the system's monitoring capability and response speed. In the event of controller failure or abnormality, the system can automatically switch to a safe operating mode or perform emergency braking to ensure that the wiper can still run at low speed or stop safely, thereby effectively reducing the failure rate, preventing single-point failure, improving overall reliability and functional safety level, and meeting the requirements of modern vehicles, especially autonomous vehicles, for high safety and high controllability. Attached Figure Description

[0021] By incorporating the figures in this article and subsequently the appendix Figure 1 The specific embodiments used to illustrate certain principles of this utility model will make other features and advantages of the method of this utility model clearer or more specifically explained.

[0022] Figure 1 A schematic diagram of a drive control device for a wiper motor according to an exemplary embodiment of the present invention is shown. Detailed Implementation

[0023] The drive control device for a wiper motor according to the present invention will now be described with reference to the accompanying drawings and embodiments. In the following description, numerous specific details are set forth to enable those skilled in the art to gain a more complete understanding of the present invention. However, it will be apparent to those skilled in the art that implementations of the present invention may not include some of these specific details. Instead, the present invention may be conceived to be practiced with any combination of the following features and elements, regardless of whether they relate to different embodiments. Therefore, the following aspects, features, embodiments, and advantages are for illustrative purposes only and should not be construed as elements or limitations of the claims.

[0024] To address the issues of low diagnostic coverage, inability to achieve real-time monitoring and rapid protection, and insufficient functional safety level in traditional windshield wiper control systems using relay solutions, this invention proposes an intelligent windshield wiper drive and control scheme based on electronic switches. By employing a half-bridge drive motor and adding an independent fault-safe control path, it can maintain low-speed operation of the wipers even in the event of functional safety failure or software reset. Simultaneously, by introducing an enable switch and high-priority control logic, it achieves precise control and rapid shutdown of the wiper power supply, thereby improving the system's reliability and functional safety level.

[0025] Figure 1 A schematic diagram of a drive control device for a wiper motor according to an exemplary embodiment of the present invention is shown.

[0026] like Figure 1 As shown, the drive and control device includes a half-bridge circuit, a power supply, a power switch, a first drive chip, a second drive chip, a controller, and a monitoring unit.

[0027] The half-bridge circuit is connected to the wiper motor M and is used to drive the wiper motor to rotate forward or backward. This half-bridge circuit consists of a high-side switch SW1 and a low-side switch SW2, and the control terminals of the high-side and low-side switches are connected to a first driver chip. For example, the high-side and low-side switches can be N-channel or P-channel MOSFETs or IGBTs, and the wiper motor is driven by the first driver chip.

[0028] The first driver chip controls the wiper motor by switching the high-side and low-side switching transistors on and off. For example, when the wiper motor needs to rotate forward, the first driver chip controls the high-side switching transistor to turn on and the low-side switching transistor to turn off; when the wiper motor needs to rotate in reverse, the first driver chip controls the low-side switching transistor to turn on and the high-side switching transistor to turn off.

[0029] The power supply powers the half-bridge circuit, providing the electrical energy needed for the wiper motor to operate. The power supply can be the vehicle's battery or power regulated by a DC / DC converter.

[0030] A power switch is positioned between the power supply and the half-bridge circuit to connect or disconnect the power supply path from the power supply to the half-bridge circuit. The power switch can use power semiconductor devices such as MOSFETs and IGBTs, and controlling its on / off state controls the power supply to the half-bridge circuit.

[0031] The first driver chip is connected to the control terminal of the half-bridge circuit and is used to drive the half-bridge circuit to make the wiper motor rotate forward or backward. The first driver chip receives control signals from the controller and controls the on / off state of the switching transistors in the half-bridge circuit according to the control signals, thereby realizing the drive control of the wiper motor.

[0032] The second driver chip is connected to the control terminal of the power switch and is used to drive the power switch to perform on / off operations. The second driver chip receives control signals from the controller or fault-safe signals from the monitoring unit, and controls the on / off state of the power switch according to the received signals. For example... Figure 1 As shown, the control signal and fail-safe signal are connected to the second driver chip via a logic OR gate.

[0033] Controller ( Figure 1(Not shown) Connected to the first and second driver chips, the controller sends corresponding control signals to the first and second driver chips respectively. This controller can be a microcontroller (MCU), field-programmable gate array (FPGA), or application-specific integrated circuit (ASIC) chip with data processing and logic control functions. Based on the wiper control request signal received from the vehicle's electronic control unit, the controller generates corresponding control signals and sends them to the first and second driver chips to achieve drive control of the wiper motor.

[0034] The monitoring unit is configured to monitor the controller's operating status in real time and output a fail-safe signal to the first and second driver chips when a controller fault is detected. The monitoring unit can be a watchdog circuit. Under normal conditions, the controller continuously outputs a "feed the watchdog" signal to the watchdog circuit. If this "feed the watchdog" signal is not received, it indicates a potential controller fault. In this case, the watchdog circuit triggers a reset operation on the controller and outputs a fail-safe signal to the first and second driver chips, ensuring the system can still operate safely under fault conditions.

[0035] The second driver chip is configured to keep the power switch on upon receiving either a control signal or a fail-safe signal. Even in the event of a controller failure, the second driver chip can maintain the power switch on based on the fail-safe signal, ensuring the wiper motor can continue operating and improving system safety and reliability.

[0036] The first drive chip is configured to drive the wiper motor to rotate forward or reverse based on control signals when the controller is in a normal state, and to drive the wiper motor into a safety protection state based on a fail-safe signal when the controller is in a fault state. The safety protection state can be a low-speed operating state of the wiper motor, ensuring that the wipers can still maintain basic functions in the event of a fault, thereby improving driving safety.

[0037] The controller is further configured to monitor the operating status of the wiper motor in real time, and send an emergency braking signal to the first drive chip when a wiper motor malfunction is detected, so as to stop the wiper motor from operating. For example, when the controller detects a fault such as stall or overcurrent in the wiper motor, it immediately sends an emergency braking signal to the first drive chip, which then controls the switching transistor in the half-bridge circuit to turn off, stopping the wiper motor and preventing the fault from escalating.

[0038] The drive control device further includes a power supply unit ( Figure 1(Not shown) and an enable switch for controlling the on / off state of the power supply path from the power supply unit to the second driver chip, the control terminal of which is connected to the controller. The power supply unit can be the vehicle's ignition signal power supply KL15 or a power supply regulated by a DC / DC converter, used to provide operating power to the second driver chip. The enable switch can be a switching device such as a MOSFET or a relay, and its on / off state is controlled to achieve power supply control for the second driver chip.

[0039] The controller is further configured to monitor the operating status of the wiper motor in real time, and to cut off the enable switch when a wiper motor malfunction is detected, thereby causing the second drive chip to shut off its power switch. For example, when the controller detects a serious malfunction in the wiper motor, it immediately controls the enable switch to open, cutting off the power supply to the second drive chip, causing the second drive chip to stop working, and then shutting off the power switch, cutting off the power supply to the half-bridge circuit, ensuring system safety.

[0040] An exemplary embodiment of this utility model also provides a vehicle wiper system, which includes a wiper motor and the aforementioned drive control device. The drive control device is connected to the wiper motor to control its operation. The vehicle wiper system can be a front windshield wiper system or a rear windshield wiper system. The drive control device enables intelligent control of the wiper motor, improving the system's reliability and safety.

[0041] The wiper motor drive control device of this utility model adopts an electronic switch instead of a traditional relay, and combines half-bridge drive, dual-drive chip control, fault-safe signal mechanism and watchdog monitoring technologies to achieve precise control and real-time fault diagnosis of the wiper motor power supply path, significantly improving the system's monitoring capability and response speed. In the event of controller failure or abnormality, the system can automatically switch to a safe operating mode or perform emergency braking to ensure that the wiper can still run at low speed or stop safely, thereby effectively reducing the failure rate, preventing single-point failure, improving overall reliability and functional safety level, and meeting the requirements of modern vehicles, especially autonomous vehicles, for high safety and high controllability.

[0042] Those skilled in the art will understand that the steps of the method according to this utility model are not limited to being performed in the order listed above. Furthermore, in this utility model, terms such as "comprising" and "including" indicate that, in addition to the steps directly and explicitly stated in the specification and claims, the technical solution of this application does not exclude the presence of other steps not directly or explicitly stated.

[0043] Although the present invention has been disclosed above with reference to preferred embodiments, it is not limited thereto. Any modifications and alterations made by those skilled in the art without departing from the spirit and scope of the present invention should be included within the protection scope of the present invention. Therefore, the protection scope of the present invention should be determined by the scope defined in the claims.

Claims

1. A drive control device for a windshield wiper motor, the drive control device comprising a half-bridge circuit connected to the windshield wiper motor and a power supply for supplying power to the half-bridge circuit, characterized in that, The drive control device also includes: A power switch is disposed between the power source and the half-bridge circuit, and is used to connect or disconnect the power supply path from the power source to the half-bridge circuit. The first driving chip is connected to the control terminal of the half-bridge circuit and is used to drive the half-bridge circuit to make the wiper motor rotate forward or reverse. The second driver chip is connected to the control terminal of the power switch and is used to drive the power switch to perform on / off operations. A controller, connected to first and second driver chips to send corresponding control signals to the first and second driver chips respectively; and A monitoring unit is configured to monitor the operating status of the controller in real time, and to output a fault safety signal to the first and second driver chips when the controller is detected to be in a fault state. The second driving chip is configured to keep the power switch on when it receives either the control signal or the fault safety signal. The first driving chip is configured to drive the wiper motor to rotate forward or reverse based on the control signal when the controller is in a normal state, and to drive the wiper motor to enter a safety protection state based on the fault safety signal when the controller is in a fault state.

2. The drive control device for a wiper motor according to claim 1, characterized in that, The monitoring unit is a watchdog timer, which is configured to trigger a reset operation of the controller when a fault is detected in the controller.

3. The drive control device for a wiper motor according to claim 1 or 2, characterized in that, The controller is further configured to monitor the operating status of the wiper motor in real time, and send an emergency braking signal to the first drive chip when a wiper motor malfunction is detected, so as to stop the wiper motor from operating.

4. The drive control device for a wiper motor according to claim 1 or 2, characterized in that, The drive control device further includes a power supply unit and an enable switch for connecting the power supply unit to the second drive chip, the control terminal of which is connected to the controller.

5. The drive control device for a wiper motor according to claim 4, characterized in that, The controller is further configured to monitor the operating status of the wiper motor in real time, and to cut off the enable switch when a wiper motor malfunction is detected, so that the second drive chip turns off the power switch.

6. The drive control device for a wiper motor according to claim 1 or 2, characterized in that, The half-bridge circuit is composed of a high-side switch and a low-side switch, and the control terminals of the high-side switch and the low-side switch are connected to the first driver chip.

7. A vehicle windshield wiper system, characterized in that, The vehicle's windshield wiper system includes: Wiper motor; and The drive control device according to any one of claims 1 to 6, wherein the drive control device is connected to the wiper motor to control the operation of the wiper motor.

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