Decoupling type electronic braking system based on redundant braking

Abstract

The invention discloses a decoupling type electronic braking system based on redundant braking. The decoupling type electronic braking system comprises a pedal integration unit; the pedal integration unit sends a control signal to the brake pressure building unit, pressure building, pressure maintaining and pressure reducing control is conducted on at least two wheels of an automobile through the brake pressure building unit, and the wheels comprise two front wheels and two rear wheels; the backup unit is used for monitoring a hydraulic pressure signal generated by the brake pressure building unit in the control process, assisting hydraulic pressure control and carrying out backup pressure building on front wheels of the automobile; the backup unit further comprises two pile-up valves and two plunger pumps, and the plunger pumps are connected with a backup voltage buildup motor. According to the system, in the working condition of long-time working of a low-attached ABS and the like, when the plunger liquid amount of the active pressure building assembly is consumed to be lower than a certain threshold value, and the plunger needs to rapidly return and supplement liquid, the system can be achieved only by closing the pressure increasing valve, and the active pressure building assembly does not need to act any more.

Description

Technical Field

[0001] The invention relates to the technical field of automobile braking, and in particular to a decoupled electronic braking system based on redundant braking. Background Art

[0002] When the existing integrated braking system is in normal working mode, the master cylinder isolation valve and the active pressure building component isolation valve will be powered on, decoupling the driver's operation on the brake pedal from the pressure building of the active pressure building component. The vehicle's braking intention can be collected and calculated by the pedal displacement sensor, or the braking target can be input to the integrated braking system through other vehicle modules such as ADAS (Advanced Driver Assistance System) for execution.

[0003] The existing integrated braking system is connected to the backup braking module. When the integrated braking system fails and enters the fail-safe backup mode, all solenoid valves are powered off and not controlled. The brake hydraulic pressure generated by the driver cannot be decoupled from the backup braking module. The hydraulic pressure generated by stepping on the brake pedal will enter the wheel cylinder. At this time, if the backup braking module performs anti-lock control, a new pressure relief path must be designed. Therefore, for this design scheme, the pressure relief valve must be retained.

[0004] If the driver has stepped on the brake pedal, one round of backup unit is required to maintain pressure, and the other round of backup unit is required to increase pressure, then the motor drives a pair of plunger pumps to work simultaneously. At this time, the single suction valve of the circuit requiring pressure maintenance must be in the valve core closed state, otherwise the hydraulic pressure of this circuit will inevitably be pressurized. At this time, since the actual pressure of the wheel cylinder exceeds the required pressure maintenance pressure, and the integrated valve cannot be used to release pressure because the driver has applied braking force, the only thing to do is to open the pressure reducing valve to reduce pressure. However, since the pressure reducing valve can only be controlled on and off and cannot control the valve core opening, it will cause a large deviation in pressure control, which will greatly affect the braking control effect. Therefore, for this design scheme, the suction valve must be retained.

[0005] In long-term working conditions such as low-attachment ABS, when the plunger fluid of the active pressure building component is consumed below a certain threshold and the plunger needs to return quickly to replenish fluid, this must be achieved by relying on the isolation valve of the active pressure building component to isolate the wheel cylinder hydraulic pressure. Summary of the invention

[0006] The purpose of the present invention is to solve the shortcomings in the prior art and to propose a decoupled electronic brake system based on redundant braking.

[0007] In order to achieve the above object, the present invention adopts the following technical solution: a decoupled electronic braking system based on redundant braking, comprising:

[0008] Pedal integrated unit;

[0009] The pedal integrated unit sends a control signal to the brake pressure building unit, and the brake pressure building unit controls the pressure building, pressure maintenance and pressure reduction of at least two wheels of the vehicle.

[0010] The wheels include two front wheels and two rear wheels;

[0011] A backup unit monitors the hydraulic pressure signal generated by the brake pressure building unit during the control process, assists in hydraulic pressure control and performs backup pressure building on the front wheels of the vehicle;

[0012] The backup unit also includes two integrated valves and two plunger pumps, and the plunger pumps are connected to the backup pressure-building motor.

[0013] As a further description of the above technical solution: the pedal integrated unit includes: a brake pedal, which is connected to a pedal simulator via a first sensor. The first sensor is provided with two for collecting displacement signals and pressure signals and sending them to the brake pressure building unit.

[0014] As a further description of the above technical solution: the brake pressure building unit includes: a fluid storage tank, the fluid storage tank is connected to an active pressure building component, the active pressure building component is connected to four boost valves, and the boost valve is connected in series with the wheel through the integrated valve.

[0015] As a further description of the above technical solution: the liquid storage tank is also connected to four pressure reducing valves, and the pressure reducing valves are connected in parallel with the boosting valves.

[0016] As a further description of the above technical solution: the backup unit is connected to the liquid storage tank, the backup unit includes a second sensor, and the second sensor is connected to any one of the front wheels.

[0017] As a further description of the above technical solution: two integrated valves are provided, a one-way valve is connected in parallel on the outside of the integrated valve, and the one-way valve is connected in series with the plunger pump.

[0018] As a further description of the above technical solution: the boost valve, the pressure reducing valve and the integrated valve are two-position two-way solenoid valves.

[0019] As a further description of the above technical solution: when the pressure reducing valve is not powered on, it is in the disconnected position.

[0020] As a further description of the above technical solution: the pedal simulator includes one or more combinations of a hydraulic damper, a spring, a reed, and rubber.

[0021] As a further description of the above technical solution: the active pressure building component includes a motor, the output end of the motor is connected to the transmission mechanism, and the piston is driven to reciprocate through the transmission mechanism.

[0022] The above technical solution has the following advantages or beneficial effects:

[0023] 1. By improving the design of the braking system, the number of solenoid valves in the system is reduced, the cost is reduced, and at the same time, redundant power-assisted braking capabilities are provided, and wheel cylinder pressure regulation can be achieved, thereby achieving redundant backup for the anti-lock braking function and body stability control function.

[0024] 2. The pedal integrated unit, brake pressure building unit and backup unit can be installed, disassembled and replaced independently. Compared with the integrated brake system, it is easier to maintain and optimizes the structural space by reducing the number of solenoid valves.

[0025] 3. The one-way valve design is cancelled for the boost valve. In long-term working conditions such as low-attachment ABS, when the plunger fluid of the active pressure-building component is consumed below a certain threshold and the plunger needs to return quickly to replenish fluid, this can be achieved by simply closing the boost valve, and the active pressure-building component no longer needs to be equipped with other solenoid valves. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] Figure 1 It is a structural diagram of the existing backup pressure building system;

[0027] Figure 2 This is a schematic diagram of the structure of the electronic braking system proposed by the present invention.

[0028] Legend:

[0029] 1. Pedal integrated unit; 2. Brake pressure building unit; 3. Backup unit; 4. Front wheel; 5. Rear wheel; 6. Pedal simulator; 7. First sensor; 8. Brake pedal; 9. Fluid reservoir; 10. Active pressure building component; 11. Boost valve; 12. Pressure reducing valve; 13. Second sensor; 14. Integrated valve; 15. Plunger pump; 16. Backup pressure building motor. DETAILED DESCRIPTION

[0030] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0031] Reference Figure 2An embodiment of the present invention provides: a decoupled electronic brake system based on redundant braking, comprising: a pedal integrated unit 1; the pedal integrated unit 1 sends a control signal to a brake pressure building unit 2, and the brake pressure building unit 2 controls at least two wheels of a car to build pressure, maintain pressure, and reduce pressure, and the wheels include two front wheels 4 and two rear wheels 5; a backup unit 3 monitors the hydraulic pressure signal generated by the brake pressure building unit 2 during the control process, assists in hydraulic pressure control and backup pressure building for the front wheels 4 of the car; the backup unit 3 also includes two integrated valves 14 and two plunger pumps 15, and the plunger pump 15 is connected to a backup pressure building motor 16.

[0032] In this embodiment, pedal braking simulation is performed by the pedal integration unit 1, and the displacement and pressure of the brake pedal 8 during the braking process are monitored by the first sensor 7, and a corresponding control signal is generated and sent to the brake pressure building unit 2. The brake pressure building unit 2 is used to respond to the braking requirements of the driver or modules such as ADAS, and to build pressure, maintain pressure, and reduce pressure on a single wheel or multiple wheels. The brake pressure building unit 2 is used to build pressure, maintain pressure, and reduce pressure on the wheels of the vehicle, and the backup unit 3 is used to assist the front wheels 4 in hydraulic pressure control and backup pressure building. The hydraulic pressure of the two front wheels 4 can be adjusted separately, and it has the backup capabilities of braking assistance, anti-lock braking function and body stability control function for the front wheels 4, and can perform braking control, anti-lock braking control, body stability control and other functions according to the needs of the driver or the needs from systems such as ADAS.

[0033] The inventor found in the research that the front wheels of the car play a dominant role in braking and stability control. Considering the cost and utility, this solution backs up the braking capacity of the front wheels. This module can realize backup power-assisted braking and wheel cylinder pressure regulation, thereby realizing redundant backup of anti-lock braking function and vehicle stability control function. Through the backup unit 3, redundant backup of brake fluid pressure failure is performed. Two integrated valves 14 are provided, which are connected in series with the boost valve 11 connected to the front wheel 4; the liquid storage tank 9 is connected to the plunger pump 15, and the plunger pump 15 is connected to the backup pressure-building motor 16.

[0034] When building pressure, the brake fluid can flow freely from the fluid storage tank 9 to the plunger pump 15. When pressure building is required, the backup pressure building motor 16 starts working, driving the plunger pump 15 to build up the fluid pressure. At the same time, the integrated valve 14 is powered on and controlled according to the required brake pressure and its changing trend. When pressure reduction is required, the integrated valve 14 can reduce the current to achieve opening control or fully open the valve core to reduce pressure. When pressure maintenance is required, the actions of the integrated valve 14 and the backup pressure building motor 16 can be coordinated and controlled to achieve constant pressure control for a single wheel.

[0035] The pedal integrated unit 1 includes: a brake pedal 8 , which is connected to a pedal simulator 6 via a first sensor 7 . Two first sensors 7 are provided for collecting displacement signals and pressure signals and sending them to the brake pressure building unit 2 .

[0036] In this embodiment, two first sensors 7 are provided, namely a displacement sensor and a pressure sensor, which are connected to the brake pedal 8 to monitor the displacement information and pressure information of the brake pedal 8, respectively, collect the driver's braking intention, collect the speed and force of the driver stepping on the brake pedal to comprehensively judge the size and speed of the required braking. In order to achieve the ability to support redundant power-assisted braking, the displacement sensor and the pressure sensor adopt two independent power supply solutions to power the displacement sensor and the pressure sensor respectively, so as to ensure that the brake pedal 8 can still have the data monitoring function in the event of a power failure.

[0037] The brake pressure building unit 2 includes: a fluid reservoir 9, the fluid reservoir 9 is connected to an active pressure building component 10, the active pressure building component 10 is connected to four boosting valves 11, and the boosting valves 11 are connected in series with the wheels through an integrated valve 14; the fluid reservoir 9 is also connected to four pressure reducing valves 12, and the pressure reducing valves 12 are connected in parallel with the boosting valves 11.

[0038] In this embodiment, the fluid storage tank 9 is used to store brake fluid, provide the brake fluid required for braking and contain the brake fluid discharged when the wheel is depressurized through the pressure reducing valve 12; the active pressure building mechanism 10 includes a motor, a transmission mechanism, and a plunger, wherein the motor is the power source, the transmission mechanism converts the rotational motion of the motor into appropriate linear motion and pushes the plunger piston to build pressure, the transmission mechanism can be a ball screw or a worm gear and a gear rack (not shown), and the plunger pressurizes the brake fluid and transmits it to each wheel to achieve braking.

[0039] By designing four boost valves 11 and four pressure reducing valves 12, the boost, pressure maintaining and pressure reducing actions of each wheel can be controlled independently, supporting the system to realize the anti-lock braking function and the vehicle body stability control function. The present application only designs the boost valve 11 without using a one-way valve. In long-term working conditions such as low-attachment ABS, when the plunger fluid volume of the active pressure building mechanism is consumed below a certain threshold and the plunger needs to return quickly to replenish fluid, this can be achieved by closing the boost valve.

[0040] The two wheel cylinders of the rear wheel 5 rely on the EPB module (electronic parking brake module, prior art, no detailed description) for backup braking, and its control instructions come from this system. After the backup pressure is built up for the front wheel 4, the corresponding control instructions are sent to the EPB module according to the braking signal of the front wheel 4. When redundant braking occurs, if the rear wheel 5 has an EPB module, the braking force of the front wheel 4 is generated by the hydraulic pressure of the redundant braking module, and the braking force of the rear wheel 5 is realized by controlling the EPB of this system; if the rear wheel 5 does not have an EPB module, the braking force of the front wheel 4 is generated by the hydraulic pressure of the redundant braking module, and the braking force of the rear wheel 5 is not controlled, so as to realize the backup of the failed braking force of the front wheel 4 and the rear wheel 5 respectively.

[0041] The backup unit 3 is connected to the fluid storage tank 9 . The backup unit 3 includes a second sensor 13 . The second sensor 13 is connected to any one of the front wheels 4 .

[0042] In this embodiment, the second sensor 13 is a pressure sensor, which is used to collect the hydraulic pressure generated by the brake pressure building unit 2 and assist in system diagnosis functions such as pressure control and hydraulic leakage.

[0043] Two integrated valves 14 are provided, and a one-way valve is connected in parallel outside the integrated valve 14 , and the one-way valve is connected in series with the plunger pump 15 .

[0044] In this embodiment, the pressure of the fluid storage tank 9 is atmospheric pressure, and the inlet of the plunger pump 15 is not affected by the pressure difference caused by braking. The requirements for the structural strength of the inlet are low, and an intake valve may not be installed. During normal operation, due to the one-way valve on one side of the outlet of the plunger pump 15, the brake pressure generated by the system will not leak into the fluid storage tank 9. When the system is in redundant backup braking, only the backup pressure-building motor 16 is needed to directly drive the plunger pump 15 to work, so as to suck the brake fluid from the fluid storage tank 9 into the plunger pump 15 and achieve the effect of boosting pressure.

[0045] The boost valve 11, the pressure reducing valve 12 and the integrated valve 14 are two-position two-way solenoid valves; when the pressure reducing valve 12 is not powered on, it is in the disconnected position.

[0046] In this embodiment, the boost valve 11 and the integrated valve 14 are in the on state when not powered on. When the brake pedal 8 is pressed and displacement and pressure signals are generated, the fluid reservoir 9 directly delivers the brake fluid to the front wheels 4 and the rear wheels 5 for braking. When backup pressure building is required, the pressure reducing valve 12 is controlled to be powered on, and the backup pressure building operation for the front wheels 3 or the rear wheels 5 is achieved through the cooperation between the pressure reducing valve 12 and the boost valve 11.

[0047] The pedal simulator 6 includes one or more combinations of hydraulic dampers, springs, reeds, and rubbers, and transmits force to the driver's feet through the pedal. It can simulate the displacement and pressure generated by pressing down the actual brake pedal during braking.

[0048] Finally, it should be noted that the above is only a preferred embodiment of the present invention and is not intended to limit the present invention. Although the present invention has been described in detail with reference to the aforementioned embodiments, it is still possible for those skilled in the art to modify the technical solutions described in the aforementioned embodiments or to make equivalent substitutions for some of the technical features therein. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims

1. A decoupled electronic braking system based on redundant braking, characterized in that: include: Pedal integrated unit (1); The pedal integrated unit (1) sends a control signal to a brake pressure building unit (2), and the brake pressure building unit (2) controls at least two wheels of the vehicle to build pressure, maintain pressure, and reduce pressure. The wheels include two front wheels (4) and two rear wheels (5); A backup unit (3) monitors the hydraulic pressure signal generated by the brake pressure building unit (2) during the control process, assists in hydraulic pressure control and performs backup pressure building on the front wheels (4) of the vehicle; The backup unit (3) further comprises two integrated valves (14) and two plunger pumps (15), wherein the plunger pumps (15) are connected to a backup pressure-building motor (16).

2. A decoupled electronic braking system based on redundant braking according to claim 1, characterized in that: The pedal integrated unit (1) comprises: a brake pedal (8), wherein the brake pedal (8) is connected to a pedal simulator (6) via a first sensor (7), wherein two first sensors (7) are provided for collecting displacement signals and pressure signals and sending them to the brake pressure building unit (2).

3. A decoupled electronic brake system based on redundant braking according to claim 1, characterized in that: The brake pressure building unit (2) comprises: a fluid storage tank (9), the fluid storage tank (9) is connected to an active pressure building component (10), the active pressure building component (10) is connected to four boost valves (11), and the boost valves (11) are connected in series with the wheels via the integrated valve (14).

4. A decoupled electronic brake system based on redundant braking according to claim 3, characterized in that: The liquid storage tank (9) is also connected to four pressure reducing valves (12), and the pressure reducing valves (12) are connected in parallel with the pressure increasing valves (11).

5. The decoupled electronic brake system based on redundant braking according to claim 3, characterized in that: The backup unit (3) is connected to the liquid storage tank (9), and the backup unit (3) comprises a second sensor (13), and the second sensor (13) is connected to any one of the front wheels (4).

6. A decoupled electronic brake system based on redundant braking according to claim 4, characterized in that: Two integrated valves (14) are provided, and a one-way valve is connected in parallel on the outside of the integrated valve (14), and the one-way valve is connected in series with the plunger pump (15).

7. A decoupled electronic brake system based on redundant braking according to claim 4, characterized in that: The pressure-boosting valve (11), the pressure-reducing valve (12) and the integrated valve (14) are two-position, two-way solenoid valves.

8. The decoupled electronic brake system based on redundant braking according to claim 7, characterized in that: When the pressure reducing valve (12) is in an unpowered state, it is in an off position.

9. The decoupled electronic brake system based on redundant braking according to claim 2, characterized in that: The pedal simulator (6) comprises one or more combinations of a hydraulic damper, a spring, a reed, and rubber.

10. The decoupled electronic brake system based on redundant braking according to claim 3, characterized in that: The active pressure building component (10) comprises a motor, the output end of which is connected to a transmission mechanism, and the transmission mechanism drives the plunger to perform reciprocating motion.

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