A distributed full hydraulic electro-hydraulic brake system

Abstract

The present invention discloses a distributed full-hydraulic electro-hydraulic brake system and method, which consists of a fluid storage tank, an accumulator, a pressure sensor, a pressure control valve, a simulation cylinder, a two-position three-way solenoid valve, a pedal stroke sensor, a manual cylinder, a brake line, a wheel brake, a one-way valve, an electric hydraulic pump and a brake controller. Since the present invention has an accumulator, it has a redundant backup function and high safety. When the brake controller fails, as long as the electric hydraulic pump can work normally, the braking force can be output and controlled normally. Once the controller of an ordinary electro-hydraulic brake fails, the brake can only be applied by manpower. Since the electric hydraulic pump can work continuously, the brake can be used not only for passenger cars with small displacement, but also for commercial vehicles with large displacement. The present invention can achieve anti-lock braking (ABS) and vehicle stability control (ESC) by simply adjusting the thrust of the electromagnet, without the need for complex solenoid valve opening or PWM control, and has the advantages of simple control and low cost.

Description

Technical Field

[0001] The present invention relates to the technical field of automobile active safety, and in particular to a distributed full-hydraulic electro-hydraulic brake system. Background Art

[0002] In terms of braking systems, intelligent driving requires vehicles to have autonomous braking capabilities—that is, braking all or some of the wheels without the driver manipulating the brake controls. Currently, devices capable of autonomous braking include electronic hydraulic brakes (EHBs), electronic mechanical brakes (EMBs), and various electro-hydraulic servo brake systems. Distributed EHB and EMB systems, which can independently control and adjust the braking force of each wheel, are considered the next generation of braking systems. Distributed EHB systems offer broader application prospects due to their convenient human backup design and similarity to traditional car architecture.

[0003] Most of the current mainstream EHB solutions use solenoid valve groups for pressure increase and pressure relief control. For example, Chinese patent CN203753122U discloses an automatic hydraulic braking system for intelligent driving. A solenoid valve group controlled by a brake control computer is added between the brake master cylinder and the HCU of the ESC. After the solenoid valve group is installed in the original vehicle hydraulic braking system, it meets the braking requirements of manual driving and unmanned driving, and the two states of manual braking and autonomous braking can be switched. However, due to the long brake line, it is not conducive to quickly building up braking pressure and the braking response is slow. In the autonomous braking mode, the structure does not support slow pressure relief. The solenoid valve group can only achieve stepped pressure control through the opening. Therefore, the pressure regulation accuracy of the braking system is not high, and the vehicle's movement stability during autonomous braking is poor. At the same time, the solenoid valve will accumulate heat when working for a long time, which cannot meet the precise autonomous braking needs of intelligent driving vehicles at any time.

[0004] Most current mainstream EHB solutions use piston electric cylinders as the brake booster. A motor compresses the piston, pumping brake fluid into the wheel cylinder to generate braking pressure. The compression is linearly proportional to the generated braking pressure. Braking pressure is maintained by stalling the motor. Larger vehicles often require larger pistons, greater torque, or multiple motors to boost the wheel cylinders to achieve braking performance similar to that of a small family car. For example, the brake disclosed in Chinese patent application CN 111301385 A utilizes dual motors and dual master cylinders to boost the two wheel cylinders, reducing the workload of a single motor while providing mutual redundancy. To meet this goal, the weight, size, and motor cost of the piston electric cylinder are all significant constraints, meaning this design is only suitable for family sedans and small to medium-sized SUVs.

[0005] To facilitate motor-assisted reverse energy recovery during braking, more advanced electric-hydraulic brakes in electric vehicles utilize decoupled braking. This means that during normal braking, the brake pedal is connected to a simulated cylinder, outputting only a braking signal and no brake hydraulic pressure. Braking force is generated by the vehicle's drive motor, the brake's electronically controlled motor, and valves. The driver's pedal stroke is proportional to the braking force, but not necessarily to the actual compression of the brake cylinder. This design maximizes energy recovery during high-speed braking via the vehicle's motor, thereby increasing the vehicle's range. In the event of a brake controller failure, regulations require that the driver can also apply a certain amount of braking force by depressing the brake pedal to activate the wheel cylinders. Current mainstream EHB solutions employ manual backup, essentially connecting the brake pedal directly to the wheel cylinder calipers via a connecting rod and hydraulic piston, amplifying the driver's foot force to the calipers for braking. For example, in the system disclosed in Chinese patent application CN 104136291A, in the event of a controller failure, valves connect the pedal pistons directly to the wheel cylinders, allowing the driver to directly transmit pedal force to the calipers. The human backup braking force that can be achieved by this method is small and is related to the driver's leg strength, and cannot apply effective braking for a long time. Summary of the Invention

[0006] In view of the deficiencies in the prior art, the present invention aims to provide a distributed full-hydraulic electro-hydraulic brake system.

[0007] In order to achieve the above object, the present invention adopts the following technical solutions:

[0008] A distributed full-hydraulic electro-hydraulic brake system, consisting of a fluid reservoir, an accumulator, a pressure sensor, a pressure control valve, a simulation cylinder, a two-position three-way solenoid valve, a pedal travel sensor, a manual cylinder, a brake line, a wheel brake, a one-way valve, an electric hydraulic pump, and a brake controller; wherein the fluid reservoir is connected to the oil return holes of the electric hydraulic pump, the manual cylinder, and the pressure control valve, respectively; the electric hydraulic pump is connected to the oil inlet holes of the accumulator and the pressure control valve via a one-way valve and can continuously output high-pressure hydraulic oil; the oil outlet hole of the pressure control valve is connected to the wheel brake via a hydraulic line; the two-position three-way valve is connected to the manual cylinder and the simulation cylinder; the pressure sensor is used to detect the output pressure of the accumulator; and the manual cylinder is connected to the pedal travel sensor.

[0009] and an oil outlet is located in the oil pumping station, and an oil pumping station is located in the oil pumping station. The oil pumping station is located in the oil pumping station, and an oil outlet is located in the oil pumping station.

[0010] The bottom of the reaction piston is provided with a return spring, and the return spring is respectively against the bottom of the reaction piston and the inner cavity wall of the valve body; the bottom of the oil inlet valve is connected to a balance piston and is provided with a compression spring, and the two ends of the compression spring are respectively against the bottom of the oil inlet valve and the inner cavity wall of the valve body; the top of the reaction piston can extend out of the valve body and is connected to the pressure rod; the push block, pressure balance spring and mechanical brake piston are arranged in a housing, the mechanical brake piston is located above the push block, and the pressure balance spring is located between the mechanical brake piston and the push block between; one end of the shell close to the mechanical brake piston is connected to the two-position three-way valve through a hydraulic pipeline; one end of the pressure rod is connected to the electromagnet, and the other end is connected to the lower end of the push rod; the upper end of the push rod extends into the shell from the opening at the bottom of the shell and is connected to the push block, the limit ring is provided on the push rod and is located outside the shell, and the outer diameter of the limit ring is larger than the inner diameter of the opening; when the reaction piston is not subjected to downward force, the return spring exerts an upward force on it; the compression spring exerts an upward force on the oil inlet valve so that the channel between the oil inlet hole and the oil outlet hole is closed.

[0011] The present invention also provides a distributed full hydraulic electro-hydraulic braking method using the above system, the specific process is as follows:

[0012] After the brake system is powered on, the pressure sensor detects the output pressure of the accumulator and transmits it to the brake controller. If the output pressure is lower than the set value, the brake controller activates the electric hydraulic pump, pressurizing the brake fluid in the reservoir and pumping it into the accumulator until the accumulator's output pressure exceeds the set value. At this time, the pressure control valve closes, no hydraulic pressure is output, and the braking force of the wheel brake is 0.

[0013] Under the condition of wire control braking, the two-position three-way solenoid valve connects the simulation cylinder and the manual cylinder; the driver steps on the brake pedal to push the manual cylinder; at this time, the hydraulic oil in the manual cylinder flows into the simulation cylinder through the two-position three-way solenoid valve, forming a braking foot feel; at the same time, the pedal travel sensor generates an electrical signal and transmits it to the brake controller; the brake controller controls the thrust of the electromagnet of the pressure control valve according to the pedal travel signal; the electromagnet pushes the pressure rod downward, and because the limit ring presses against the bottom of the shell, the push block cannot be pushed up; then the pressure rod uses the push block as a fulcrum to press down the reaction piston; after the reaction piston is pressed down, it contacts the oil inlet valve, isolating the oil outlet hole and the oil return hole; then the oil inlet valve is pressed down, and the high-pressure hydraulic oil in the oil inlet hole flows into the oil outlet hole, and then flows to the wheel brake through the brake pipe, thereby generating braking force;

[0014] As the oil pressure at the oil outlet increases, the upward hydraulic pressure on the reaction piston increases; when the hydraulic pressure is equal to the downward pressure generated by the electromagnet pushing the pressure rod, the reaction piston is pushed upward, and the oil inlet valve moves upward, closing the channel between the oil inlet and oil outlet holes; at the same time, the reaction piston remains in contact with the oil inlet valve, and the oil outlet and oil return holes remain isolated; at this time, the brake fluid in the oil inlet hole cannot flow into the oil outlet hole, and the brake fluid in the oil outlet hole cannot flow into the oil return hole, thereby maintaining the hydraulic pressure of the oil outlet hole; by adjusting the thrust of the electromagnet, the hydraulic pressure of the oil outlet hole can be adjusted, thereby adjusting the braking force of the wheel brake;

[0015] When the driver releases the brake pedal to reduce the braking force, the brake controller reduces the thrust of the electromagnet according to the signal of the pedal travel sensor, so that it is less than the liquid pressure of the reaction piston; then the reaction piston is pushed upward, and a gap is created between it and the oil inlet valve; the brake fluid in the oil outlet hole flows into the oil return hole through the gap between the reaction piston and the oil inlet valve, and the pressure drops; until the liquid pressure of the reaction piston is balanced with the downward pressure generated by the electromagnet, the reaction piston is pressed down again and re-contacts the oil inlet valve, thereby isolating the oil outlet hole and the oil return hole and maintaining the braking force; if the driver completely releases the brake pedal, the thrust of the electromagnet is 0, and the reaction piston is completely pushed to the bottom by the reaction piston return spring, and there is always a gap between it and the oil inlet valve; then the high-pressure brake fluid in the wheel brake flows back to the fluid reservoir 1 through the oil return hole, and the braking force is 0.

[0016] Furthermore, when the brake controller receives an instruction from the vehicle controller to generate braking force, the brake controller controls the thrust of the electromagnet according to the instruction of the vehicle controller, thereby controlling the braking force of the wheel brake; the braking force at this time is completely controlled by the received external instruction, that is, external instruction braking.

[0017] Furthermore, when the brake controller fails and loses power, the two-position three-way valve connects the pressure control valve and the manual cylinder. The driver then steps on the brake pedal, and the brake fluid in the manual cylinder pushes the mechanical brake piston, which in turn pushes the push block via the pressure-balancing spring, thereby pushing the pressure rod downward. The pressure rod then uses the electromagnet as a fulcrum to depress the reaction piston. After being depressed, the reaction piston contacts the oil inlet valve, isolating the oil outlet from the oil return hole. The oil inlet valve is then depressed, and high-pressure hydraulic oil flows from the oil inlet hole into the oil outlet hole, and then flows through the brake pipe to the wheel brake, thereby generating braking force.

[0018] As the oil pressure at the oil outlet hole increases, the upward liquid pressure on the reaction piston increases, and the reaction piston is pushed upward, compressing the pressure balance spring; at the same time, the oil inlet valve moves upward; when the liquid pressure is equal to the downward pressure generated by the pressure balance spring pushing the pressure rod, the reaction piston contacts the oil inlet valve, closing the channel between the oil inlet and the oil outlet, and isolating the oil outlet from the oil return hole; at this time, the brake fluid in the oil inlet hole cannot flow to the oil outlet hole, and the brake fluid in the oil outlet hole cannot flow to the oil return hole, thereby maintaining the hydraulic pressure of the oil outlet hole; the driver can adjust the hydraulic pressure of the oil outlet hole by adjusting the force of pressing the brake pedal, thereby adjusting the braking force of the wheel brake. The working condition at this time is mechanical braking, and the braking force is controlled by the pressure of the manual cylinder and the mechanical brake piston; at this time, as long as the electric hydraulic pump and pressure sensor can work normally, the brake can maintain normal working condition.

[0019] Furthermore, when the thrust of one or more electromagnets is independently controlled, the output pressure of each pressure regulating valve can be independently controlled, thereby making the braking force of each wheel brake different, realizing ABS and ESC functions.

[0020] Furthermore, after multiple braking operations, when the pressure in the accumulator drops, the electric hydraulic pump restarts to pump high-pressure brake fluid into the accumulator to restore the pressure in the accumulator.

[0021] Furthermore, when the braking system is damaged or the power is lost, the two-position three-way valve connects the mechanical brake piston and the manual cylinder; when the driver steps on the brake pedal, the high-pressure brake fluid in the accumulator can be used to perform several braking operations, which is emergency braking.

[0022] The beneficial effects of the present invention are as follows: compared with ordinary electro-hydraulic brakes and ABS and ESC systems, the system of the present invention has a redundant backup function and high safety due to the accumulator. When the brake controller fails, as long as the electric hydraulic pump can work normally, the braking force can be output and controlled normally. However, once the controller of an ordinary electro-hydraulic brake fails, braking can only be performed by manpower. Since the electric hydraulic pump of the present invention can work continuously, the brake can be used not only for passenger cars with small displacement, but also for commercial vehicles with large displacement. Compared with ordinary ABS and ESC systems, the present invention can achieve anti-lock braking (ABS) and vehicle stability control (ESC) by simply adjusting the thrust of the electromagnet, without the need for complex solenoid valve opening or PWM control, and has the advantages of simple control and low cost. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] Figure 1 Schematic diagram of the overall distributed full hydraulic electro-hydraulic brake system in Example 1 of the present invention;

[0024] Figure 2 Schematic diagram of the structure of the pressure control valve in Example 1 of the present invention;

[0025] Figure 3 Schematic diagram of the distributed full hydraulic electro-hydraulic brake system in brake-by-wire mode in the second embodiment of the present invention;

[0026] Figure 4 This is a schematic diagram of the distributed full hydraulic electro-hydraulic brake system in brake-by-wire mode in state 2 of the second embodiment of the present invention;

[0027] Figure 5 Schematic diagram of the distributed full hydraulic electro-hydraulic brake system in brake-by-wire mode in state 3 of the second embodiment of the present invention;

[0028] Figure 6 This is a schematic diagram of the operation of the distributed full-hydraulic electro-hydraulic brake system when the brake controller fails and loses power in Example 2 of the present invention. DETAILED DESCRIPTION

[0029] The present invention will be further described below in conjunction with the accompanying drawings. It should be noted that this embodiment is based on the technical solution and provides a detailed implementation method and specific operation process, but the protection scope of the present invention is not limited to this embodiment.

[0030] Example 1

[0031] This embodiment provides a distributed full hydraulic electro-hydraulic brake system, such as Figure 1As shown, it consists of a fluid storage tank 1, an accumulator 2, a pressure sensor 3, a pressure control valve 4, a simulation cylinder 5, a two-position three-way solenoid valve 6, a pedal stroke sensor 7, a manual cylinder 8, a brake line 9, a wheel brake 10, a one-way valve 11, an electric hydraulic pump 12 and a brake controller (not shown in the figure); wherein the fluid storage tank 1 is respectively connected to the electric hydraulic pump 12, the manual cylinder 8 and the return oil hole 47 of the pressure control valve 4; the electric hydraulic pump 12 is connected to the oil inlet hole 41 of the accumulator 2 and the pressure control valve 4 through the one-way valve 11, and can continuously output high-pressure hydraulic oil; the oil outlet hole 415 of the pressure control valve 4 is connected to the wheel brake 10 through the hydraulic line 9; the two-position three-way valve 6 is connected to the manual cylinder 8 and the simulation cylinder 5; the pressure sensor 3 is used to detect the output pressure of the accumulator 2; the manual cylinder 8 is connected to the pedal stroke sensor 7.

[0032] like Figure 1 As shown, four pressure control valves 4 and two accumulators 2 are provided in this embodiment.

[0033] The pressure control valve 4 is the core component of the entire brake system. Figure 2 As shown, the pressure control valve 4 is composed of a valve body, an oil inlet hole 41, a balancing piston 42, a compression spring 43, an oil inlet valve 44, a return spring 45, a reaction piston 46, an oil return hole 47, a push rod 48, a limiting ring 49, a push block 410, a pressure balancing spring 411, a mechanical brake piston 412, an electromagnet 413, a pressure rod 414 and an oil outlet hole 415. Figure 2 As shown; the balancing piston 42, the compression spring 43, the oil inlet valve 44, the return spring 45 and the reaction piston 46 are all arranged in the inner cavity of the valve body, and the reaction piston 46 is located above the oil inlet valve 44 and can be separated from or contacted with the oil inlet valve 44 by moving up and down; the oil inlet hole 41, the oil return hole 47 and the oil outlet hole 415 are arranged on both sides of the valve body and communicate with the inner cavity of the valve body, wherein the oil outlet hole 415 and the oil return hole 47 are respectively located on both sides of the reaction piston 43, and the oil inlet hole 41 and the oil outlet hole 415 are located on the same side of the valve body, and the oil inlet hole 41 is located lower than the oil outlet hole 415;

[0034] A return spring 45 is provided at the bottom of the reaction piston 46, which respectively abuts against the bottom of the reaction piston 46 and the inner wall of the valve body. A balancing piston 42 is connected to the bottom of the oil inlet valve 44, and a compression spring 43 is provided. The two ends of the compression spring 43 respectively abut against the bottom of the oil inlet valve 44 and the inner wall of the valve body. The top of the reaction piston 46 can extend out of the valve body and is connected to the pressure rod 414.

[0035] The push block 410, the pressure balance spring 411, and the mechanical brake piston 412 are arranged in a housing, the mechanical brake piston 412 is located above the push block 410, and the pressure balance spring 411 is located between the mechanical brake piston 412 and the push block 410; the end of the housing close to the mechanical brake piston 412 is connected to the two-position three-way valve 6 through a hydraulic pipeline; one end of the pressure rod 414 is connected to the electromagnet 413, and the other end is connected to the lower end of the push rod 48; the upper end of the push rod 48 extends into the housing from the opening at the bottom of the housing and is connected to the push block 210, the limit ring 49 is provided on the push rod 48 and is located outside the housing, and the outer diameter of the limit ring 49 is larger than the inner diameter of the opening; when the reaction piston 46 is not subjected to downward force, the return spring 45 exerts an upward force on it; the compression spring 43 exerts an upward force on the oil inlet valve 44 so that the channel between the oil inlet hole 41 and the oil outlet hole 415 is closed.

[0036] It should be noted that when the reaction piston 46 is no longer under downward force, the reaction piston return spring 45 pushes it upward to its limit position. At this point, the brake fluid in the wheel brake 10 can flow through the gap between the reaction piston 46 and the inlet valve 44 into the oil return hole 47, thereby returning to the fluid reservoir 1, reducing the braking force to zero. Simultaneously, the inlet valve 44's compression spring 43 pushes the inlet valve 44 upward, closing the passage between the inlet hole 41 and the outlet hole 415. At this point, no matter how high the pressure in the inlet hole 41 is, brake fluid will not flow from the inlet hole 41 into the outlet hole 415. The high-pressure brake fluid in the inlet hole 41 exerts an upward force on the inlet valve 44 and a downward force on the balancing piston 42. These two forces are equal in magnitude and cancel each other out. Therefore, as long as the force of the compression spring 43 is overcome, the inlet valve 44 can be opened.

[0037] Example 2

[0038] This embodiment provides a distributed full-hydraulic electro-hydraulic braking method using the system described in Example 1. The method includes five operating conditions: wire control braking, external command braking, mechanical braking, anti-lock braking (ABS), electronic stability control (ESC), and emergency braking. The specific process is as follows:

[0039] When the brake system is powered on, pressure sensor 3 detects the output pressure of accumulator 2 and transmits it to the brake controller. If the output pressure falls below a set value, the brake controller activates electric hydraulic pump 12, which pressurizes the brake fluid in reservoir 1 and pumps it into accumulator 2 until the output pressure of accumulator 2 exceeds the set value. At this point, pressure control valve 4 closes, no hydraulic pressure is output, and the braking force of wheel brake 10 is zero.

[0040] Under brake-by-wire conditions, the two-position, three-way solenoid valve 6 connects the simulated cylinder 5 and the manual cylinder 8. The driver presses the brake pedal, pushing the manual cylinder 8. The hydraulic oil in the manual cylinder 8 then flows through the two-position, three-way solenoid valve 6 into the simulated cylinder 5, creating a braking feel. Simultaneously, the pedal travel sensor 7 generates an electrical signal, which is transmitted to the brake controller. The brake controller controls the thrust of the electromagnet 413 of the pressure control valve 4 based on the pedal travel signal. Figure 3 As shown, electromagnet 413 pushes down on pressure rod 414. Because stop ring 49 abuts the bottom of the housing, push block 410 cannot be pushed upward. Consequently, pressure rod 414, using push block 410 as a fulcrum, depresses reaction piston 46. Once depressed, reaction piston 46 contacts oil inlet valve 44, isolating oil outlet 415 from oil return port 47. Oil inlet valve 44 is then depressed, allowing high-pressure hydraulic oil in oil inlet 41 to flow into oil outlet 415 and then through brake line 9 to wheel brake 10, generating braking force.

[0041] As the oil pressure at the oil outlet 415 increases, the upward liquid pressure on the reaction piston 46 increases. When the liquid pressure is equal to the downward pressure generated by the electromagnet 413 pushing the pressure rod 414, the reaction piston 46 is pushed upward, and the oil inlet valve 44 moves upward, closing the channel between the oil inlet 41 and the oil outlet 415. At the same time, the reaction piston 46 remains in contact with the oil inlet valve 44, and the oil outlet 415 and the oil return hole 47 remain isolated. At this time, the brake fluid in the oil inlet hole 41 cannot flow to the oil outlet 415, and the brake fluid in the oil outlet 415 cannot flow to the oil return hole 47, thereby maintaining the hydraulic pressure of the oil outlet 415. By adjusting the thrust of the electromagnet 413, the hydraulic pressure of the oil outlet 415 can be adjusted, thereby adjusting the braking force of the wheel brake 10. As Figure 4 shown.

[0042] When the driver releases the brake pedal and reduces the braking force, the brake controller reduces the thrust of the electromagnet 413 according to the signal of the pedal travel sensor 7, so that it is less than the liquid pressure of the reaction piston 46. Then the reaction piston 46 is pushed upward, and a gap is generated between it and the oil inlet valve 44. The brake fluid in the oil outlet hole 415 flows into the oil return hole 47 through the gap between the reaction piston 46 and the oil inlet valve 44, and the pressure drops. Until the liquid pressure of the reaction piston 46 is balanced with the downward pressure generated by the electromagnet 413, the reaction piston is pressed down again and re-contacts the oil inlet valve 44, thereby isolating the oil outlet hole 415 from the oil return hole 47 and maintaining the braking force. If the driver completely releases the brake pedal, the thrust of the electromagnet 413 is 0, and the reaction piston 46 is completely pushed to the bottom by the reaction piston return spring 45, and there is always a gap between it and the oil inlet valve 44. Then the high-pressure brake fluid in the wheel brake 10 flows back to the fluid reservoir 1 through the oil return hole 47, and the braking force is 0. Figure 5 shown.

[0043] When the brake controller receives a command from the vehicle controller to generate braking force, it controls the thrust of the electromagnet according to the command of the vehicle controller, thereby controlling the braking force of the wheel brake 10. At this time, the braking force is completely controlled by the received external command, that is, external command braking.

[0044] When the brake controller fails and loses power, the two-position, three-way valve 6 connects the pressure control valve 4 and the manual cylinder 8. The driver then depresses the brake pedal. The brake fluid in the manual cylinder 8 pushes the mechanical brake piston 412, which in turn pushes the push block 410 via the pressure-balancing spring 411, thereby pushing the pressure rod 414 downward. The pressure rod 414 then uses the electromagnet 413 as a fulcrum to depress the reaction piston 46. Once depressed, the reaction piston 46 contacts the oil inlet valve 44, isolating the oil outlet 415 from the oil return port 47. The oil inlet valve 44 is then depressed, and high-pressure hydraulic oil flows from the oil inlet 41 into the oil outlet 415, then through the brake line 9 to the wheel brake 10, generating braking force.

[0045] As the oil pressure at the oil outlet 415 increases, the upward liquid pressure on the reaction piston 46 increases, and the reaction piston 46 is pushed upward, compressing the pressure balance spring 411. At the same time, the oil inlet valve 44 moves upward. When the liquid pressure is equal to the downward pressure generated by the pressure balance spring 411 pushing the pressure rod 414, the reaction piston 46 contacts the oil inlet valve 44, closing the channel between the oil inlet 41 and the oil outlet 415, and the oil outlet 415 is isolated from the oil return hole 47. At this time, the brake fluid in the oil inlet 41 cannot flow to the oil outlet 415, and the brake fluid in the oil outlet 415 cannot flow to the oil return hole 47, thereby maintaining the hydraulic pressure of the oil outlet 415. The driver can adjust the hydraulic pressure of the oil outlet 415 by adjusting the force of pressing the brake pedal, thereby adjusting the braking force of the wheel brake 10. The working condition at this time is mechanical braking, and the braking force is controlled by the pressure of the manual cylinder 8 and the mechanical brake piston 412. At this time, as long as the electric hydraulic pump 12 and the pressure sensor 3 can work normally, the brake can maintain a normal working state. Figure 6 shown.

[0046] When the thrust of one or more electromagnets 413 is independently controlled, the output pressure of each pressure regulating valve can be independently controlled, so that the braking force of each wheel brake 10 is different, realizing the ABS and ESC functions.

[0047] After multiple braking operations, when the pressure in the accumulator drops, the electric hydraulic pump 12 is restarted to pump the high-pressure brake fluid into the accumulator to restore the pressure in the accumulator.

[0048] When the brake system is damaged or powered off, the two-position three-way valve 6 connects the mechanical brake piston 412 and the manpower cylinder 8. When the driver steps on the brake pedal, the high-pressure brake fluid of the accumulator can also be used to brake several times, which is an emergency brake.

[0049] Those skilled in the art can make various corresponding changes and modifications based on the above technical solutions and concepts, and all of these changes and modifications should be included in the scope of protection of the claims of the present invention.

Claims

1. A distributed full hydraulic electro-hydraulic brake system, characterized in that: It consists of a fluid storage tank, an accumulator, a pressure sensor, a pressure control valve, a simulation cylinder, a two-position three-way solenoid valve, a pedal travel sensor, a manual cylinder, a brake line, a wheel brake, a one-way valve, an electric hydraulic pump, and a brake controller; wherein the fluid storage tank is respectively connected to the oil return holes of the electric hydraulic pump, the manual cylinder, and the pressure control valve; the electric hydraulic pump is connected to the oil inlet holes of the accumulator and the pressure control valve through a one-way valve and can continuously output high-pressure hydraulic oil; the oil outlet hole of the pressure control valve is connected to the wheel brake through a hydraulic line; the two-position three-way valve is connected to the manual cylinder and the simulation cylinder; the pressure sensor is used to detect the output pressure of the accumulator; and the manual cylinder is connected to the pedal travel sensor; and an oil outlet is located in the oil pumping station, and an oil pumping station is located in the oil pumping station. The oil pumping station is located in the oil pumping station, and an oil outlet is located in the oil pumping station. The bottom of the reaction piston is provided with a return spring, and the return spring is respectively against the bottom of the reaction piston and the inner cavity wall of the valve body; the bottom of the oil inlet valve is connected to a balance piston and is provided with a compression spring, and the two ends of the compression spring are respectively against the bottom of the oil inlet valve and the inner cavity wall of the valve body; the top of the reaction piston can extend out of the valve body and is connected to the pressure rod; the push block, pressure balance spring and mechanical brake piston are arranged in a housing, the mechanical brake piston is located above the push block, and the pressure balance spring is located between the mechanical brake piston and the push block between; one end of the shell close to the mechanical brake piston is connected to the two-position three-way valve through a hydraulic pipeline; one end of the pressure rod is connected to the electromagnet, and the other end is connected to the lower end of the push rod; the upper end of the push rod extends into the shell from the opening at the bottom of the shell and is connected to the push block, the limit ring is provided on the push rod and is located outside the shell, and the outer diameter of the limit ring is larger than the inner diameter of the opening; when the reaction piston is not subjected to downward force, the return spring exerts an upward force on it; the compression spring exerts an upward force on the oil inlet valve so that the channel between the oil inlet hole and the oil outlet hole is closed.

2. A distributed full hydraulic electro-hydraulic braking method using the system of claim 1, characterized in that: The specific process is: After the brake system is powered on, the pressure sensor detects the output pressure of the accumulator and transmits it to the brake controller. If the output pressure is lower than the set value, the brake controller activates the electric hydraulic pump, pressurizing the brake fluid in the reservoir and pumping it into the accumulator until the accumulator's output pressure exceeds the set value. At this time, the pressure control valve closes, no hydraulic pressure is output, and the braking force of the wheel brake is 0. Under the condition of wire control braking, the two-position three-way solenoid valve connects the simulation cylinder and the manual cylinder; the driver steps on the brake pedal to push the manual cylinder; at this time, the hydraulic oil in the manual cylinder flows into the simulation cylinder through the two-position three-way solenoid valve, forming a braking foot feel; at the same time, the pedal travel sensor generates an electrical signal and transmits it to the brake controller; the brake controller controls the thrust of the electromagnet of the pressure control valve according to the pedal travel signal; the electromagnet pushes the pressure rod downward, and because the limit ring presses against the bottom of the shell, the push block cannot be pushed up; then the pressure rod uses the push block as a fulcrum to press down the reaction piston; after the reaction piston is pressed down, it contacts the oil inlet valve, isolating the oil outlet hole and the oil return hole; then the oil inlet valve is pressed down, and the high-pressure hydraulic oil in the oil inlet hole flows into the oil outlet hole, and then flows to the wheel brake through the brake pipe, thereby generating braking force; As the oil pressure at the oil outlet increases, the upward hydraulic pressure on the reaction piston increases. When the hydraulic pressure equals the downward pressure generated by the electromagnet pushing the pressure rod, the reaction piston is pushed upward, and the oil inlet valve moves upward, closing the passage between the oil inlet and oil outlet holes. At the same time, the reaction piston remains in contact with the oil inlet valve, and the oil outlet and oil return holes remain isolated. At this time, the brake fluid in the oil inlet hole cannot flow into the oil outlet hole, and the brake fluid in the oil outlet hole cannot flow into the oil return hole, thereby maintaining the hydraulic pressure of the oil outlet holes. By adjusting the thrust of the electromagnet, the hydraulic pressure of the oil outlet can be adjusted, thereby adjusting the braking force of the wheel brake; When the driver releases the brake pedal to reduce the braking force, the brake controller reduces the thrust of the electromagnet according to the signal of the pedal travel sensor, so that it is less than the liquid pressure of the reaction piston; then the reaction piston is pushed upward, and a gap is created between it and the oil inlet valve; the brake fluid in the oil outlet hole flows into the oil return hole through the gap between the reaction piston and the oil inlet valve, and the pressure drops; until the liquid pressure of the reaction piston is balanced with the downward pressure generated by the electromagnet, the reaction piston is pressed down again and re-contacts the oil inlet valve, thereby isolating the oil outlet and the oil return hole and maintaining the braking force; if the driver completely releases the brake pedal, the thrust of the electromagnet is 0, and the reaction piston is completely pushed to the bottom by the reaction piston return spring, and there is always a gap between it and the oil inlet valve; then the high-pressure brake fluid in the wheel brake flows back to the fluid reservoir through the oil return hole, and the braking force is 0.

3. The method according to claim 2, characterized in that When the brake controller receives an instruction from the vehicle controller to generate braking force, the brake controller controls the thrust of the electromagnet according to the instruction of the vehicle controller, thereby controlling the braking force of the wheel brake; the braking force at this time is completely controlled by the external instruction received, that is, external command braking.

4. The method according to claim 2, characterized in that When the brake controller fails and loses power, the two-position three-way valve connects the pressure control valve and the manual cylinder. The driver then steps on the brake pedal, and the brake fluid in the manual cylinder pushes the mechanical brake piston, which in turn pushes the push block via the pressure-balancing spring, pushing the pressure rod downward. The pressure rod then uses the electromagnet as a fulcrum to depress the reaction piston. After the reaction piston is depressed, it contacts the oil inlet valve, isolating the oil outlet from the oil return hole. The oil inlet valve is then depressed, and high-pressure hydraulic oil flows from the oil inlet hole into the oil outlet hole, and then through the brake pipe to the wheel brake, generating braking force. As the oil pressure at the oil outlet hole increases, the upward liquid pressure on the reaction piston increases, and the reaction piston is pushed upward, compressing the pressure balance spring; at the same time, the oil inlet valve moves upward; when the liquid pressure is equal to the downward pressure generated by the pressure balance spring pushing the pressure rod, the reaction piston contacts the oil inlet valve, closing the channel between the oil inlet and the oil outlet, and isolating the oil outlet from the oil return hole; at this time, the brake fluid in the oil inlet hole cannot flow to the oil outlet hole, and the brake fluid in the oil outlet hole cannot flow to the oil return hole, thereby maintaining the hydraulic pressure of the oil outlet hole; the driver can adjust the hydraulic pressure of the oil outlet hole by adjusting the force of pressing the brake pedal, thereby adjusting the braking force of the wheel brake. The working condition at this time is mechanical braking, and the braking force is controlled by the pressure of the manual cylinder and the mechanical brake piston; at this time, as long as the electric hydraulic pump and pressure sensor can work normally, the brake can maintain normal working condition.

5. The method according to claim 2, characterized in that When the thrust of one or several electromagnets is controlled independently, the output pressure of each pressure regulating valve can be controlled independently, so that the braking force of each wheel brake is different, realizing ABS and ESC functions.

6. The method according to claim 2, characterized in that After multiple braking operations, when the pressure in the accumulator drops, the electric hydraulic pump restarts and pumps high-pressure brake fluid into the accumulator to restore the pressure in the accumulator.

7. The method according to claim 2, characterized in that When the braking system is damaged or the power is lost, the two-position three-way valve connects the mechanical brake piston and the manual cylinder; when the driver steps on the brake pedal, the high-pressure brake fluid in the accumulator can be used to brake several times, which is emergency braking.

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