Hydraulic brake-by-wire system

Abstract

The utility model relates to the technical field of brake-by-wire systems, in particular to a hydraulic brake-by-wire system which is provided with double pressure source control, a first BSM module and a second BSM module can independently provide brake fluid, when one of the first BSM module and the second BSM module loses a hydraulic power source, the other of the first BSM module and the second BSM module still has the hydraulic power source, the pressure of the first BSM module and the pressure of the second BSM module are adjusted and controlled in a split-axis mode, and the brake fluid can be independently supplied. Compared with a traditional hydraulic braking system with four wheels controlled by the same pressure source, when a heavy-duty vehicle enters EBD control, front wheels are independently pressurized without being influenced by pressure relief of the rear wheels while pressure relief of the rear wheels, braking force loss can be reduced, the first BSM and the second BSM communicate and interact through a private CAN during normal work, and when the private CAN breaks down, the braking force loss is reduced. The first BSM transmits a pedal travel signal to the second BSM through the whole vehicle public CAN; when the first BSM breaks down, a pedal travel signal is transmitted to the second BSM through the hard wire PWM, and in addition, the liquid supply amount of brake liquid can meet the requirements for brake time and brake deceleration of a larger-tonnage automobile or truck in the mode that the two WCBSs control two wheels respectively.

Description

Technical Field

[0001] The utility model relates to the technical field of wire control braking systems, in particular to a hydraulic wire control braking system. Background Technique

[0002] In recent years, the rapid development of electric vehicles has also driven the research and application of new braking systems. The wire control braking system has been greatly pursued. At present, the wire control braking system is mainly divided into two braking structures: electro-hydraulic and electro-mechanical. However, the current wire control braking solutions are mainly concentrated in the field of small-tonnage passenger cars. For commercial vehicles with a relatively larger curb weight, due to the limitation of braking capacity, there are not many applications.

[0003] For example, Chinese Patent Publication No. CN110116718A discloses a wire-controlled hydraulic braking system. By reasonably connecting various solenoid valves, brushless motors, worm gears, rack and pinions, pedal feel simulators, master cylinders, liquid storage tanks, and brakes through a hydraulic circuit, a fully decoupled wire-controlled hydraulic braking function is realized, and the wire-controlled basic braking function, the pressure maintaining function of the anti-lock braking system, the pressure reducing function of the anti-lock braking system, the liquid supplementing function of the pressure intensifying cylinder of the anti-lock braking system, the active pressure intensifying function, and the leakage failure detection function in the self-checking detection circuit can be completed.

[0004] However, the applicant found that in the hydraulic wire control braking system disclosed in the above comparative patent, usually four braking loads (wheels) are controlled by one pressure source (pressure intensifying cylinder). Due to the limitation of the braking fluid provided by the pressure intensifying cylinder, it can only provide the required braking fluid for small-tonnage vehicles to meet the braking time and deceleration requirements, and cannot meet the fluid demand of the brake calipers of larger-tonnage vehicles, reducing the adaptability of the hydraulic wire control braking system. Summary of the Utility Model

[0005] In view of this, the purpose of the present utility model is to provide a hydraulic wire control braking system to solve the problem that in the existing hydraulic wire control braking system, usually four braking loads (wheels) are controlled by the same pressure source, and pressure shaft regulation cannot be performed. When a heavy vehicle enters EBD control, when the rear axle relieves pressure, the front wheel pressurization is easily affected by the rear wheel pressure relief, resulting in braking force loss.

[0006] For the above purposes, the present utility model provides a hydraulic line control braking system, including a hydraulic system, which is a dual-pressure source system composed of BSM one and BSM two. The BSM one and BSM two perform signal interaction through hard-wired PWM, private CAN, and public CAN. It also includes braking load one, braking load two, braking load three, braking load four, a first brake fluid flow pipeline, and a second brake fluid flow pipeline. The BSM one controls braking load one and braking load two respectively through the two first brake fluid flow pipelines, and the BSM two controls braking load three and braking load four respectively through the two second brake fluid flow pipelines.

[0007] Preferably, the BSM one includes ECU one, a first brake fluid boosting system, a master cylinder, a pedal, and a displacement sensor. The master cylinder is connected to the pedal through a piston in its cylinder body. The displacement sensor is installed on the piston in the master cylinder to achieve synchronous movement of the displacement sensor and the piston, so that the displacement sensor can detect the displacement of the input push rod of the pedal. Both of the two first brake fluid flow pipelines are connected to the first brake fluid boosting system.

[0008] Preferably, the BSM two includes ECU two and a second brake fluid boosting system. Both of the two second brake fluid flow pipelines are connected to the second brake fluid boosting system. The ECU one and ECU two perform signal interaction through private CAN and public CAN.

[0009] Preferably, a pressure sensor is arranged in the cylinder body of the master cylinder, and the pressure sensor is used to detect the pressure in the master cylinder.

[0010] Preferably, the displacement sensor performs signal interaction with ECU two through hard-wired PWM.

[0011] Preferably, when the private CAN fails, the BSM two cannot obtain the target pressure signal transmitted from the private CAN. That is, when the private CAN communication between the BSM one and BSM two fails, the BSM one can send the pedal stroke signal of the BSM one to the BSM two through the public CAN, and the BSM two establishes pressure according to the internal algorithm program.

[0012] Preferably, when the ECU one in the BSM one fails and cannot send signals to the private CAN and public CAN, the displacement sensor sends the stroke PWM signal to ECU two through hard-wired PWM, and the ECU two builds pressure according to the received PWM signal.

[0013] The beneficial effects of the present utility model are as follows: First, it has dual-pressure source control. The two modules of BSM one and BSM two in this system can independently provide brake fluid. When one module loses the hydraulic power source, the other module still has a hydraulic power source to provide hydraulic braking, and the two modules do not interfere with each other.

[0014] II. Dual CAN channel redundancy. When working normally, BSM-1 and BSM-2 exchange information through the private CAN communication. BSM-1 transmits the driver's requested target pressure to BSM-2 for execution through the private CAN. When the private CAN fails, BSM-1 transmits the brake pedal stroke signal to BSM-2 through the vehicle's public CAN, and BSM-2 performs pressure control according to the pedal stroke.

[0015] III. Hard-wired backup of the pedal stroke signal. When BSM-1 fails, the displacement sensor transmits the detected pedal stroke signal to BSM-2 in the form of hard-wired PWM, and BSM-2 performs pressure control according to the pedal stroke.

[0016] IV. Pressure axis regulation of BSM-1 and BSM-2. Compared with the traditional hydraulic braking system in which the four braking loads (i.e., the four wheels) are controlled by the same pressure source, when the heavy vehicle enters the EBD control, while the rear wheels relieve pressure, the front wheels can be independently pressurized without being affected by the rear wheel pressure relief, reducing braking force loss. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] In order to more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the following will briefly introduce the drawings required for the description of the embodiments or the prior art. Obviously, the drawings in the following description are only the embodiments of the present invention. For those of ordinary skill in the art, without creative efforts, other drawings can also be obtained based on these drawings.

[0018] Figure 1 It is a system block diagram of an embodiment of the present invention.

[0019] In the figure: 1. BSM-1; 2. BSM-2; 3. Hard-wired PWM; 4. Private CAN; 5. Public CAN; 6. Braking load 1; 7. Braking load 2; 8. Braking load 3; 9. Braking load 4; 10. Brake fluid flow pipeline 1; 11. Brake fluid flow pipeline 2; 12. ECU-1; 13. Brake fluid boosting system 1; 14. Master cylinder; 15. Pedal; 16. Displacement sensor; 17. ECU-2; 18. Brake fluid boosting system 2; 19. Pressure sensor. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0020] In order to make the purpose, technical solutions and advantages of the present invention clearer and more understandable, the following will further describe the present invention in detail with reference to specific embodiments and the accompanying drawings.

[0021] It should be noted that, unless otherwise defined, the technical terms or scientific terms used in the embodiments of the present utility model should have the ordinary meanings understood by those with ordinary skills in the field to which the present utility model belongs. The "first", "second" and similar terms used in the present utility model do not denote any order, quantity or importance, but are only used to distinguish different components. The terms such as "including" or "comprising" mean that the elements or objects appearing before this word cover the elements or objects listed after this word and their equivalents, without excluding other elements or objects. The terms such as "connected" or "linked" are not limited to physical or mechanical connections, but may include electrical connections, whether direct or indirect. The terms such as "upper", "lower", "left" and "right" are only used to indicate relative position relationships. When the absolute position of the object being described changes, the relative position relationships may also change accordingly.

[0022] As Figure 1 shown, a hydraulic line control braking system includes a hydraulic system, which is a dual-pressure source system composed of BSM-1 and BSM-2. BSM-1 and BSM-2 perform signal interaction through hard wire PWM3, private CAN4 and public CAN5. It also includes a braking load-1 6, a braking load-2 7, a braking load-3 8, a braking load-4 9, a brake fluid flow pipeline-1 10 and a brake fluid flow pipeline-2 11. BSM-1 controls the braking load-1 6 and the braking load-2 7 respectively through two brake fluid flow pipelines-1 10, and BSM-2 controls the braking load-3 8 and the braking load-4 9 respectively through two brake fluid flow pipelines-2 11.

[0023] By setting BSM-1 and BSM-2, BSM-1 can control the braking load-1 6 and the braking load-2 7 respectively by controlling two brake fluid flow pipelines-1 10, while BSM-2 can control the braking load-3 8 and the braking load-4 9 respectively by controlling two brake fluid flow pipelines-2 11, so that the two modules of BSM-1 and BSM-2 in this system can independently provide brake fluid. When one of them loses the hydraulic power source, the other still has a hydraulic power source to provide hydraulic braking, and the two modules do not interfere with each other. In addition, by controlling the braking load-1 6 and the braking load-2 7 through BSM-1, and controlling the braking load-3 8 and the braking load-4 9 through BSM-2, it is possible to provide the required brake fluid for large-tonnage vehicles or trucks, so that when the heavy-duty vehicle enters the EBD control, while the rear wheels release pressure, the front wheels can be independently pressurized without being affected by the rear-wheel pressure release, reducing the braking force loss.

[0024] In a preferred embodiment of the present utility model, BSM-1 includes ECU-12, a brake fluid boosting system-13, a master cylinder 14, a pedal 15, and a displacement sensor 16. The brake fluid boosting system-13, the displacement sensor 16, and the pressure sensor 19 are all electrically connected to ECU-12. The master cylinder 14 is connected to the pedal 15 through a piston in its cylinder body. The displacement sensor 16 is installed on the piston in the master cylinder 14 to achieve synchronous movement with the piston, so that the displacement sensor 16 can detect the displacement of the input push rod of the pedal 15. Both of the two brake fluid flow pipelines-10 are connected to the brake fluid boosting system-13. The brake fluid boosting system generally refers to a system that increases the braking force by increasing the brake fluid pressure. Such a system can be electronically controlled or mechanically assisted. The purpose of the boosting system is to make the braking response more rapid and powerful, especially in the case of emergency braking. The brake fluid boosting system belongs to the existing conventional technology.

[0025] When the system is powered on, when the driver steps on the pedal 15 and moves forward, after the displacement sensor 16 detects that the displacement of the input push rod exceeds the set threshold, ECU-12 controls the brake fluid boosting system-13 to perform pressure building for the braking load-6 or the braking load-7 according to the displacement signal of the input push rod of the pedal 15. At the same time, ECU-12 transmits the displacement signal detected by the displacement sensor 16 to BSM-2 through the private CAN4. BSM-2 performs pressure building for the braking load-8 or the braking load-9 by controlling the brake fluid flow pipeline-11 according to the received signal.

[0026] In another preferred embodiment of the present utility model, BSM-2 includes ECU-17 and a brake fluid boosting system-18. Both of the two brake fluid flow pipelines-11 are connected to the brake fluid boosting system-18. ECU-12 and ECU-17 perform signal interaction through the private CAN4 and the public CAN5.

[0027] A pressure sensor 19 is arranged in the cylinder body of the master cylinder 14, and the pressure sensor 19 is used to detect the pressure in the master cylinder 14.

[0028] Dual CAN channel redundancy. During normal operation, BSM-1 and BSM-2 communicate and interact through the private CAN4. BSM-1 transmits the driver's requested target pressure to BSM-2 through the private CAN4 for execution. When the private CAN4 fails, BSM-2 cannot obtain the target pressure signal transmitted from the private CAN4. That is, when the private CAN4 communication between BSM-1 and BSM-2 fails, BSM-1 can send the pedal stroke signal of BSM-1 to BSM-2 through the public CAN5, and BSM-2 establishes the pressure according to the internal algorithm program.

[0029] It should be noted that the displacement sensor 16 performs signal interaction with ECU-17 through the hard wire PWM3.

[0030] The hard-wired backup of the pedal stroke signal. When the ECU-12 in BSM-1 fails and cannot send signals to the private CAN4 and the public CAN5, the displacement sensor 16 sends the stroke PWM signal to the ECU-17 through the hard wire PWM3, and the ECU-17 builds pressure according to the received PWM signal.

[0031] Those of ordinary skill in the art should understand that the discussion of any of the above embodiments is merely exemplary and is not intended to imply that the scope of the present invention is limited to these examples; under the concept of the present invention, the technical features in the above embodiments or different embodiments can also be combined, the steps can be implemented in any order, and there are many other variations in different aspects of the present invention as described above, which are not provided in detail for the sake of brevity.

[0032] The embodiments of the present invention are intended to cover all such substitutions, modifications, and variations that fall within the broad scope of the appended claims. Therefore, any omissions, modifications, equivalent substitutions, improvements, etc. made within the spirit and principle of the present invention shall be included within the protection scope of the present invention.

Claims

1. A hydraulic wire control braking system, characterized in that, It includes a hydraulic system, which is a dual-pressure source system composed of BSM one (1) and BSM two (2). The BSM one (1) and BSM two (2) perform signal interaction through hard wire PWM (3), private CAN (4), and public CAN (5). It also includes brake load one (6), brake load two (7), brake load three (8), brake load four (9), brake fluid flow pipeline one (10), and brake fluid flow pipeline two (11). The BSM one (1) controls the brake load one (6) and the brake load two (7) respectively through two brake fluid flow pipelines one (10), and the BSM two (2) controls the brake load three (8) and the brake load four (9) respectively through two brake fluid flow pipelines two (11).

2. The hydraulic wire control braking system according to claim 1, wherein The BSM one (1) includes ECU one (12), brake fluid boosting system one (13), master cylinder (14), pedal (15), and displacement sensor (16). The master cylinder (14) is connected to the pedal (15) through a piston in its cylinder body. The displacement sensor (16) is installed on the piston in the master cylinder (14) to achieve synchronous movement of the displacement sensor (16) and the piston, so that the displacement sensor (16) can detect the input push rod displacement of the pedal (15). Both of the two brake fluid flow pipelines one (10) are connected to the brake fluid boosting system one (13).

3. The hydraulic wire control braking system according to claim 2, characterized in that, The BSM two (2) includes ECU two (17) and brake fluid boosting system two (18). Both of the two brake fluid flow pipelines two (11) are connected to the brake fluid boosting system two (18). The ECU one (12) and ECU two (17) perform signal interaction through private CAN (4) and public CAN (5).

4. A hydraulic wire control braking system according to claim 2, characterized in that, A pressure sensor (19) is arranged in the cylinder body of the master cylinder (14), and the pressure sensor (19) is used to detect the pressure in the master cylinder (14).

5. The hydraulic wire control braking system according to claim 3, wherein The displacement sensor (16) performs signal interaction with the ECU two (17) through hard wire PWM (3).

6. A hydraulic wire control braking system according to claim 1, characterized in that, When the private CAN (4) fails, the BSM two (2) cannot obtain the target pressure signal transmitted from the private CAN (4). That is, when the private CAN (4) communication between the BSM one (1) and BSM two (2) fails, the BSM one (1) can send the pedal stroke signal of the BSM one (1) to the BSM two (2) through the public CAN (5), and the BSM two (2) establishes pressure according to the internal algorithm program.

7. A hydraulic wire control braking system according to claim 3, characterized in that, When the ECU one (12) in the BSM one (1) fails and cannot send signals to the private CAN (4) and the public CAN (5), the displacement sensor (16) sends the stroke PWM signal to the ECU two (17) through the hard wire PWM (3), and the ECU two (17) builds pressure according to the received PWM signal.

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