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EP-4122785-B1 - HYDRAULIC REGULATION UNIT FOR BRAKING SYSTEM IN AUTOMOBILE, BRAKING SYSTEM AND CONTROL METHOD

EP4122785B1EP 4122785 B1EP4122785 B1EP 4122785B1EP-4122785-B1

Inventors

  • YANG, Weimiao
  • ZHANG, YONGSHENG
  • LIU, Donghao
  • ZHANG, WEI

Dates

Publication Date
20260506
Application Date
20210222

Claims (9)

  1. A hydraulic adjustment unit of a brake system in a vehicle, comprising a first fluid reservoir (29), a second fluid reservoir (2), a first oil return pipe (110), and a second oil return pipe (120), wherein: the first fluid reservoir (29) and the second fluid reservoir (2) are a same fluid reservoir, or the first fluid reservoir (29) and the second fluid reservoir (2) are different fluid reservoirs; the first oil return pipe (110) is configured to connect to wheel cylinders (151, 152) of the vehicle, so that brake fluid in the wheel cylinders (151, 152) of the vehicle is delivered to the first fluid reservoir (29), to depressurize wheel cylinders (151, 152) of the vehicle; the second oil return pipe (120) is configured to connect to the wheel cylinders (151, 152) of the vehicle through oil inlet pipes (130, 140) of the brake system, so that the brake fluid in the wheel cylinders (151, 152) of the vehicle is delivered to the second fluid reservoir (2) through the oil inlet pipes (130, 140) of the brake system, to depressurize the wheel cylinders (151, 152) of the vehicle; and, oil inlet pipes of the hydraulic adjustment unit comprise a first oil inlet pipe (130) and a second oil inlet pipe (140); characterized in that the second oil return pipe (120) is connected to the first oil inlet pipe (130) by using a first reducing valve (10); if the first reducing valve (10) is in a closed state, the second oil return pipe (120) is connected to the first oil inlet pipe (130); and if the first reducing valve (10) is in an open state, the second oil return pipe (120) is disconnected from the first oil inlet pipe (130); and the second oil return pipe (120) is connected to the second oil inlet pipe (140) by using a second reducing valve (11); if the second reducing valve (11) is in a closed state, the second oil return pipe (120) is connected to the second oil inlet pipe (140); and if the second reducing valve (11) is in an open state, the second oil return pipe (120) is disconnected from the second oil inlet pipe (140).
  2. The hydraulic adjustment unit according to claim 1, wherein the hydraulic adjustment unit comprises a master cylinder (3) and a pressure providing apparatus (18); the master cylinder (3) provides braking force to a first wheel (25) of the vehicle through a first oil inlet pipe branch (131) of the first oil inlet pipe (130), and the master cylinder (3) provides braking force to a second wheel (26) of the vehicle through a second oil inlet pipe branch (132) of the first oil inlet pipe (130); the master cylinder (3) provides braking force to a third wheel (27) of the vehicle through a third oil inlet pipe branch (141) of the second oil inlet pipe (140), and the master cylinder (3) provides braking force to a fourth wheel (28) of the vehicle through a fourth oil inlet pipe branch (142) of the second oil inlet pipe (140); the pressure providing apparatus (18) provides braking force to the first wheel (25) and the second wheel (26) through a third oil inlet pipe (150), the first oil inlet pipe branch (131), and the second oil inlet pipe branch (132); the third oil inlet pipe (150) is connected to the first oil inlet pipe branch (131); and the third oil inlet pipe (150) is connected to the second oil inlet pipe branch (132); and the pressure providing apparatus (18) provides braking force to the third wheel (27) and the fourth wheel (28) through a fourth oil inlet pipe (160), the third oil inlet pipe branch (141), and the fourth oil inlet pipe branch (142); the fourth oil inlet pipe (160) is connected to the third oil inlet pipe branch (141); and the fourth oil inlet pipe (160) is connected to the fourth oil inlet pipe branch (142).
  3. The hydraulic adjustment unit according to claim 2, wherein the first oil inlet pipe (130) is connected to the first oil inlet pipe branch (131) and the second oil inlet pipe branch (132) by using a first isolation valve (12); and if the first isolation valve (12) is in an open state, brake fluid in the first oil inlet pipe (130) is blocked by the first isolation valve (12), and cannot flow into wheel cylinders for the first wheel (25) and the second wheel (26) through the first oil inlet pipe branch (131) and the second oil inlet pipe branch (132); and the second oil inlet pipe (140) is connected to the third oil inlet pipe branch (141) and the fourth oil inlet pipe branch (142) by using a second isolation valve (13); and if the second isolation valve (13) is in an open state, brake fluid in the second oil inlet pipe (140) is blocked by the first isolation valve (12), and cannot flow into the first wheel (25) and the second wheel (26) through the third oil inlet pipe branch (141) and the fourth oil inlet pipe branch (142).
  4. A brake system in a vehicle, comprising a hydraulic adjustment unit according to any one of claims 1 to 3 and a plurality of wheel cylinders (151, 152).
  5. A vehicle, comprising the brake system according to claim 4.
  6. A control method for a brake system according to claim 4 in a vehicle, comprising: controlling, by a controller of a brake system, first control valves (16, 17) to be in a closed state, to connect a first oil return pipe (110) of the brake system to a wheel cylinder of the brake system, so that brake fluid in the wheel cylinder of the brake system flows into a first fluid reservoir (29) of the brake system through the first oil return pipe (110), to depressurize wheel cylinders (151, 152) of a vehicle; and characterized by controlling, by the controller, second control valves (10, 11) to be in a closed state, to connect oil inlet pipes (130, 140) of the brake system to a second oil return pipe (120) of the brake system, so that the brake fluid in the wheel cylinder of the brake system flows into a second fluid reservoir (2) of the brake system through the oil inlet pipes (130, 140) of the brake system and the second oil return pipe (120).
  7. The control method according to claim 6, wherein the controlling, by the controller, second control valves (10, 11) to be in a closed state comprises: if a depressurization rate of the brake system is less than a preset depressurization rate threshold, controlling, by the controller, the second control valves (10, 11) to be in a closed state.
  8. The control method according to claim 7, wherein the oil inlet pipes of the brake system comprise a first oil inlet pipe (130) and a second oil inlet pipe (140); the second oil return pipe (120) is connected to the first oil inlet pipe (130) by using a first reducing valve (10), and the second oil return pipe (120) is connected to the second oil inlet pipe (140) by using a second reducing valve (11); and the controlling, by the controller, second control valves (10, 11) to be in a closed state comprises: controlling, by the controller, the first reducing valve (10) in the second control valves (10, 11) to be in a closed state, to connect the second oil return pipe (120) to the first oil inlet pipe (130) in the oil inlet pipes of the brake system; and controlling, by the controller, the second reducing valve (11) in the second control valves (10, 11) to be in a closed state, to connect the second oil return pipe (120) to the second oil inlet pipe (140) in the oil inlet pipes of the brake system.
  9. The control method according to claim 8, wherein a master cylinder (3) of the brake system provides braking force to a first wheel (25) of the vehicle through a first oil inlet pipe branch (131) of the first oil inlet pipe (130), and provides braking force to a second wheel (26) of the vehicle through a second oil inlet pipe branch (132) of the first oil inlet pipe (130); and the master cylinder (3) provides braking force to a third wheel (27) of the vehicle through a third oil inlet pipe branch (141) of the second oil inlet pipe (140), and provides braking force to a fourth wheel (28) of the vehicle through a fourth oil inlet pipe branch (142) of the second oil inlet pipe (140); and the method further comprises: controlling, by the controller, a pressure providing apparatus (18) of the brake system to provide braking force to the first wheel (25) and the second wheel (26) through a third oil inlet pipe (150) of the brake system, the first oil inlet pipe branch (131), and the second oil inlet pipe branch (132), wherein the third oil inlet pipe (150) is connected to the first oil inlet pipe branch (131), and the third oil inlet pipe (150) is connected to the second oil inlet pipe branch (132); and controlling, by the controller, the pressure providing apparatus (18) to provide braking force for the third wheel (27) and the fourth wheel (28) through a fourth oil inlet pipe (160) of the brake system, the third oil inlet pipe branch (141), and the fourth oil inlet pipe branch (142), wherein the fourth oil inlet pipe (160) is connected to the third oil inlet pipe branch (141), and the fourth oil inlet pipe (160) is connected to the fourth oil inlet pipe branch (142).

Description

TECHNICAL FIELD This application relates to the field of vehicles, and more specifically, to a hydraulic adjustment unit of a brake system in a vehicle, a brake system in a vehicle, a vehicle, and a control method for a brake system in a vehicle. BACKGROUND A brake system in a vehicle is a system that implements forced braking on wheels of the vehicle by applying specific braking force to the wheels of the vehicle. A function of the brake system is to enable a traveling vehicle to forcibly decelerate or even stop according to a requirement of a driver or a controller, or enable a stopped vehicle to park stably under various road conditions (for example, on a ramp), or keep a speed of a vehicle traveling downhill stable. As a popular brake system, an electro-hydraulic brake (Electro-Hydraulic Brake, EHB) system usually includes a fluid reservoir configured to accommodate brake fluid. When the brake system needs to provide braking force to the wheels of the vehicle, the brake fluid in the fluid reservoir may be delivered to a supercharging device. The supercharging device pressurizes the brake fluid, to provide braking force to the wheels through an oil inlet pipe. When the brake system needs to depressurize the wheels of the vehicle, a pressure difference between pressure of the brake fluid in the fluid reservoir and pressure of brake fluid in a wheel cylinder may be used, so that the brake fluid in the wheel cylinder is delivered to the fluid reservoir through an oil return pipe, to provide braking force to the wheels next time. At present, with development of vehicle electrification and intelligence, a vehicle poses an increasingly high requirement on the brake system. After some issues such as brake-by-wire characteristic and redundancy backup are considered, the brake system also needs to meet a control requirement on high depressurization efficiency. Therefore, to meet the control requirement on the high depressurization efficiency of the brake system, a brake system with high depressurization efficiency is urgently needed. CN 102 975 706 A discloses an automobile brake boosting and controlling device, comprising a liquid storage tank (, a high-pressure gas tank, an electronic control unit and a boosting and controlling unit, wherein the boosting and controlling unit has a piston mechanism and four wheel control hydraulic pipelines; the piston mechanism is in communication with the liquid storage tank, the high-pressure gas tank and the four wheel control hydraulic pipelines, respectively; and the electronic control unit is connected to the piston mechanism and the four wheel control hydraulic pipelines by means of a circuit. US 2019/217834 A1 discloses a hydraulic control apparatus and a brake system capable of improving responsiveness in terms of increasing a pressure in a wheel cylinder. The hydraulic control apparatus includes a connection fluid passage connected to a wheel cylinder of a wheel, a first hydraulic source, and a second hydraulic source. The first hydraulic source includes a first discharge port connected to the connection fluid passage and a first intake port connected to a reservoir storing brake fluid therein. The second hydraulic source includes a second discharge port connected to the connection fluid passage and a second intake port connected to the reservoir. SUMMARY This application provides a hydraulic adjustment unit of a brake system in a vehicle, a brake system in a vehicle, a vehicle, and a control method for a brake system in a vehicle, to improve depressurization efficiency when the brake system depressurizes a wheel cylinder. According to a first aspect, a hydraulic adjustment unit of a brake system in a vehicle is provided, including a first fluid reservoir 29, a second fluid reservoir 2, a first oil return pipe 110, and a second oil return pipe 120. The first oil return pipe 110 is configured to connect to wheel cylinders 151 and 152 of a vehicle, so that brake fluid in the wheel cylinders 151 and 152 of the vehicle is delivered to the first fluid reservoir 29, to depressurize wheels of the vehicle. The second oil return pipe 120 is configured to connect to the wheel cylinders 151 and 152 of the vehicle through oil inlet pipes 130 and 140 of a brake system, so that the brake fluid in the wheel cylinders 151 and 152 of the vehicle is delivered to the second fluid reservoir 2 through the oil inlet pipes 130 and 140 of the brake system, to depressurize the wheels of the vehicle. In an embodiment of this application, the brake fluid is simultaneously delivered from the wheel cylinders 151 and 152 to the fluid reservoirs through the first oil return pipe 110 and the second oil return pipe 120, to depressurize the wheels of the vehicle. This helps improve depressurization efficiency of the brake system in depressurizing the wheel cylinders. In addition, this avoids low braking efficiency of an existing brake system, in which the wheels of the vehicle can be depressurized thr