Search

EP-4448349-B1 - BRAKE SYSTEM FOR A MOTOR VEHICLE

EP4448349B1EP 4448349 B1EP4448349 B1EP 4448349B1EP-4448349-B1

Inventors

  • COURTH, CHRISTIAN
  • BILLER, HARALD
  • HITZEL, MICHAEL

Dates

Publication Date
20260513
Application Date
20221205

Claims (12)

  1. A brake system for a motor vehicle for at least four hydraulically actuatable wheel brakes (8a-8d), said brake system comprising a first electrically actuatable pressure source (5), a first electronic control device (101), a second electrically actuatable pressure source (2), an electrically actuatable inlet valve (6a-6d) for each wheel brake and an electrically actuatable outlet valve (7a-7d) for each wheel brake, a second electronic control device (201), and a pressure medium reservoir (4), wherein the first pressure source (5) and the second pressure source (2) are connected to a brake supply line (13) to which the at least four inlet valves (6a-6d) are connected, wherein an electrically actuatable circuit separating valve (40) is arranged in the brake supply line (13) in such a manner that, when the circuit separating valve (40) is closed, the brake supply line (13) is hydraulically separated into a first line section (13a) and a second line section (13b), wherein the first line section (13a) is hydraulically connected to the second pressure source (2) and at least two of the at least four inlet valves (6a, 6b), and the second line section (13b) is hydraulically connected to the first pressure source (5) and the other, in particular at least two, of the at least four inlet valves (6c, 6d), wherein the first electronic control device (101) controls the first pressure source (5), the second electronic control device (201) controls the second pressure source (2) and the inlet and outlet valves (6a-6d, 7a-7d), and the circuit separating valve (40) are controlled by the second electronic control device (201), characterized by a first structural unit (100) in which the first electrically actuatable pressure source (5) is arranged and which comprises the first electronic control device (101), and a second structural unit (200) in which the second electrically actuatable pressure source (2), the electrically actuatable inlet and outlet valves (6a-6d, 7a-7d), and the circuit separating valve (40) are arranged and which comprises the second electronic control device (201).
  2. The brake system as claimed in claim 1, characterized in that a first electrical partition (A) and a second electrical partition (B) are provided, which are electrically independent of one another, wherein the first pressure source (5) and the first electronic control device (101) are assigned to the first electrical partition (A) and the second pressure source (2), the second electronic control device (201), the inlet and outlet valves (6a-6d, 7a-7d) and the circuit separating valve (40) are assigned to the second electrical partition (B).
  3. The brake system as claimed in claim 1 or 2, characterized in that the first pressure source (5) is controlled exclusively by the first electronic control device (101) and the second pressure source (2), the inlet and outlet valves (6a-6d, 7a-7d) and the circuit separating valve (40) are controlled exclusively by the second electronic control device (201).
  4. The brake system as claimed in claim 3, characterized in that the first structural unit (100) and the second structural unit (200) are connected to one another by at most one pressure-resistant hydraulic connecting element (80).
  5. The brake system as claimed in claim 3 or 4, characterized in that the first structural unit (100) and the second structural unit (200) are connected to one another by only one hydraulic connecting element (80), wherein said connecting element is designed to be pressure-resistant.
  6. The brake system as claimed in any one of the preceding claims, characterized in that the first pressure source (5) is connected to the brake supply line (13) via an electrically actuatable first separating valve (26), wherein the separating valve (26) is controlled by the second electronic control device (201).
  7. The brake system as claimed in claim 6, characterized in that the first separating valve (26) is designed to be normally open.
  8. The brake system as claimed in any one of the preceding claims, characterized in that the first pressure source (5) is connected to the pressure medium reservoir (4) via an electrically actuatable second separating valve (23), wherein the second separating valve (23) is controlled by the first electronic control device (101).
  9. The brake system as claimed in claim 8, characterized in that the second separating valve (23) is designed to be normally open.
  10. The brake system as claimed in any one of the preceding claims, characterized in that the first pressure source (5) is connected to the pressure medium reservoir (4) via a check valve (53) which opens in the direction of the first pressure source (5).
  11. The brake system as claimed in any one of the preceding claims, characterized in that , in addition to the first and second pressure sources (2, 5), the brake system does not comprise a further pressure source for building up a brake pressure for actuating the wheel brakes.
  12. The brake system as claimed in any one of the preceding claims, characterized by an actuating unit for a vehicle operator, wherein the actuating unit is connected to at least one electronic control device (101, 201) for transmitting a driver demand signal, and wherein there is no mechanical-hydraulic connection from the actuating unit to the wheel brakes.

Description

The invention relates to a braking system for a motor vehicle for at least four hydraulically actuated wheel brakes with a first electrically actuated pressure source, a second electrically actuated pressure source, an electrically actuated inlet valve for each wheel brake, an electrically actuated outlet valve for each wheel brake and a pressure medium reservoir. From the WO 2018/130483 A1 A braking system with two electrically controlled pressure sources for a motor vehicle with four hydraulically actuated wheel brakes is known. In addition to individually controlled electrical inlet and outlet valves for each wheel, the braking system comprises an electrically controlled circuit separator valve and at least three further electrically controlled valves. The aforementioned components are arranged together in a single unit. Furthermore, two electronic control units are provided, one of which controls the second pressure source and the inlet and outlet valves, while the first pressure source and all other valves are controlled by the other electronic control unit. In the DE 10 2018 222 478 A1 A braking system is disclosed which comprises two electrically controlled pressure sources, a brake pedal-operated master brake cylinder, individually controlled electrical inlet and outlet valves for each wheel, an electrically controlled circuit isolator valve, an electrically controlled pump valve for the second electrically controlled pressure source, and a normally closed switching valve for the first electrically controlled pressure source. The second electrically controlled pressure source, its associated pump valve, and the inlet and outlet valves are located in a second module. The master brake cylinder with its associated driver isolator valve and simulator, the first electrically controlled pressure source, and its normally closed switching valve are also included. The switching valve and the circuit separation valve are arranged in a first module. In the DE 10 2019 207088A1 A braking system is described which includes a brake pedal-operated master brake cylinder, a first and a second electrically controlled pressure supply device, and a first brake circuit pressure line section for connection to the first wheel brakes and a second brake circuit pressure line section for connection to the second wheel brakes. The suction side of the second pressure supply device is connected to the first brake pressure line section, and the pressure side is connected to the inlet valves of the associated wheel brakes. A hydraulic connection with an electrically operated release valve is provided between one of the brake circuit pressure line sections and a pressure fluid reservoir. In the DE 102017 222445 A1 A brake system is disclosed comprising a first and a second electrically controllable pressure supply device. The first pressure supply device is connected to a brake supply line to which the wheel brakes are connected. A first electrical device controls the first pressure supply device, and both are assigned to a first electrical partition. A second electrical device controls the second pressure supply device and the inlet and outlet valves. These are assigned to the second partition. In the DE 10 2017 216617 A1 A braking system is described with a first electrically controlled pressure source, which is disconnectably connected via a first isolating valve to a first brake circuit supply line, which is connected to two inlet valves. A second electrically controlled pressure source is further described, which is disconnectably connected via a second isolating valve to a second brake circuit supply line, which is connected to two other inlet valves. A circuit isolating device can connect or disconnect the two brake circuit supply lines. A first electronic device actuates the first pressure source and the second The isolation valve and a second electronic device actuate the second pressure source and the first isolation valve. It is an object of the present invention to provide an improved braking system suitable for highly automated driving, which in particular offers the highest possible availability necessary for highly automated driving. Another objective of the invention is to keep the costs for the manufacture and assembly of the brake system as low as possible. This problem is solved according to the invention by a braking system according to claim 1. The invention is based on the concept that the brake system comprises a first electrically actuated pressure source, a first electronic control device, a second electrically actuated pressure source, an electrically actuated inlet valve for each wheel brake and an electrically actuated outlet valve for each wheel brake, a second electronic control device, and a hydraulic fluid reservoir. The first pressure source and the second pressure source are connected to a brake supply line to which the at least four inlet valves are connected. An electrically actuated circuit is