Brake system having two pressure-providing devices and method for operating a brake system

Patent metadata

Field	Value
Publication number	US-10988124-B2
Application number	US-201716071701-A
Country	US
Kind code	B2
Filing date	Mar 1, 2017
Priority date	Mar 4, 2016
Publication date	Apr 27, 2021
Grant date	Apr 27, 2021

Abstract

A brake installation for a motor vehicle. First and second pressure provision devices build up brake pressure in the wheel brakes. The first pressure device connected to a first wheel brake of a first brake circuit and to a second wheel brake of the first brake circuit. The second pressure device connected to a third wheel brake of a second brake circuit and to a fourth wheel brake of the second brake circuit. Each pressure device is respectively activated by an open-loop/closed-loop control unit. A first hydraulic line, with a normally open isolating valve, connects the first wheel brake line of the first brake circuit to the first wheel brake line of the second brake circuit. A second hydraulic line, with a normally open isolating valve, connects the second wheel brake line of the first brake circuit to the second wheel brake line of the second brake circuit.

First claim

The invention claimed is:

1. A brake installation for a motor vehicle, having four hydraulic wheel brakes which are assigned in each case to one vehicle wheel, comprising:
a brake pedal, which is assigned a travel sensor arrangement for identifying a braking demand, and having a first and a second pressure provision device for building up brake pressure in the wheel brakes,
wherein the first pressure provision device is hydraulically connected via a first wheel brake line to a first wheel brake of the four hydraulic wheel brakes assigned to a first brake circuit and is hydraulically connected via a second wheel brake line to a second wheel brake of the four hydraulic wheel brakes assigned to the first brake circuit, and wherein the second pressure provision device is hydraulically connected via a third wheel brake line to a third wheel brake of the four hydraulic wheel brakes assigned to a second brake circuit and is hydraulically connected via a fourth wheel brake line to a fourth wheel brake of the four hydraulic wheel brakes assigned to the second brake circuit, wherein each of the first and second pressure provision devices is respectively activated by a separate respective open-loop and closed-loop control unit,
a first hydraulic connecting line, into which an isolating valve which is open when electrically deenergized is connected, connects one of the first and second wheel brake lines of the first brake circuit to one of the third and fourth wheel brake lines of the second brake circuit, and
a second hydraulic connecting line, into which an isolating valve which is open when electrically deenergized is connected, connects another one of the first and second wheel brake lines of the first brake circuit to another one of the third and fourth wheel brake lines of the second brake circuit,
wherein when each of the isolating valves are closed, each of the first and second pressure provision devices is capable of building up pressure in the wheel brakes of only one brake circuit.

2. The brake installation as claimed in claim 1 , wherein, in a normal operating mode, in which the first and second pressure provision devices build up brake pressure, at least one of the separate respective open-loop and closed-loop control units switches the isolating valves into their isolating position, such that in each case one of the first and second pressure provision devices builds up the pressure in the wheel brakes of the only one brake circuit.

3. The brake installation as claimed in claim 1 , wherein one wheel valve, which is open when electrically deenergized, is connected into the respective wheel brake line, which wheel valve is opened by at least one of the separate respective open-loop and closed-loop control units for the purposes of a wheel-specific build-up of pressure in the respective wheel brake.

4. The brake installation as claimed in claim 1 , wherein one sequence valve which is closed when electrically deenergized is connected into each of the first, second, third and fourth wheel brake lines.

5. The brake installation as claimed in claim 4 , wherein, in the event of a failure of one of the first and second pressure provision devices, the sequence valves in the wheel brake lines by which the failed pressure provision device is connected to the wheel brakes switch, in an electrically deenergized state, into their isolating position.

6. The brake installation as claimed in claim 1 , wherein each of the first and second pressure provision devices has exactly one pressure space and one piston which is movable into said pressure space for the purposes of building up pressure.

7. The brake installation as claimed in claim 1 , wherein, in a normal operating mode, each of the first and second brake circuits is assigned two wheel brakes which impart a braking action on a same vehicle axle.

8. The brake installation as claimed in claim 1 , wherein an actuation apparatus is provided which is hydraulically connectable to each of the four hydraulic wheel brakes and by which the driver can build up pressure in the wheel brakes when he or she actuates the brake pedal by muscle force.

9. The brake installation as claimed in claim 8 , wherein the actuation unit is formed as a tandem master brake cylinder.

10. The brake installation as claimed in claim 2 , wherein one wheel valve, which is open when electrically deenergized, is connected into the respective wheel brake line, which wheel valve is opened by at least one of the separate respective open-loop and closed-loop control units for the purposes of a wheel-specific build-up of pressure in the respective wheel brake.

11. The brake installation as claimed in claim 1 , wherein the first pressure provision device is connected to the wheel brakes of the second brake circuit solely by way of at least one of the first and second hydraulic connecting lines, and the second pressure provision device is connected to the wheel brakes of the first brake circuit solely by way of at least one of the first and second hydraulic connecting lines.

12. A brake installation for a motor vehicle, having four hydraulic wheel brakes which are assigned in each case to one vehicle wheel, comprising:
a brake pedal, which is assigned a travel sensor arrangement for identifying a braking demand, and having a first and a second pressure provision device for building up brake pressure in the wheel brakes,
wherein the first pressure provision device is hydraulically connected via a first wheel brake line to a first wheel brake of the four hydraulic wheel brakes assigned to a first brake circuit and is hydraulically connected via a second wheel brake line to a second wheel brake of the four hydraulic wheel brakes assigned to the first brake circuit, and wherein the second pressure provision device is hydraulically connected via a third wheel brake line to a third wheel brake of the four hydraulic wheel brakes assigned to a second brake circuit and is hydraulically connected via a fourth wheel brake line to a fourth wheel brake of the four hydraulic wheel brakes assigned to the second brake circuit, wherein each of the first and second pressure provision devices is respectively activated by an open-loop and closed-loop control unit,
a first hydraulic connecting line, into which an isolating valve which is open when electrically deenergized is connected, connects one of the first and second wheel brake lines of the first brake circuit to one of the third and fourth wheel brake lines of the second brake circuit, and
a second hydraulic connecting line, into which an isolating valve which is open when electrically deenergized is connected, connects another one of the first and second wheel brake lines of the first brake circuit to another one of the third and fourth wheel brake lines of the second brake circuit,
wherein the respective pressure provision device has two pressure chambers, wherein each of the two pressure chambers is hydraulically connected or connectable to a different brake of the same brake circuit.

13. A method for operating a brake installation for a motor vehicle, having four hydraulic wheel brakes which are assigned in each case to one vehicle wheel,
having a brake pedal which is assigned a travel sensor arrangement for identifying a braking demand,
and having a first and a second pressure provision device for building up brake pressure in the wheel brakes,
wherein the first pressure provision device is hydraulically connected via a wheel brake line to a first wheel brake of the four hydraulic wheel brakes assigned to a first brake circuit and is hydraulically connected via a wheel brake line to a second wheel brake of the four hydraulic w

Assignees

• Continental Teves Ag & Co Ohg

Inventors

• Besier Marco
• Stauder Peter
• Jungbecker Johann
• Drumm Stefan
• Roll Georg
• Böhm Jürgen
• Linhoff Paul

Classifications

• B60T8/348 Primary

  4 Channel systems (B60T8/345 takes precedence) · CPC title

• B60T8/3645

  having more than one electromagnetic coil inside a common housing · CPC title

• B60T8/326

  Hydraulic systems · CPC title

• B60T2270/82

  Brake-by-Wire, EHB · CPC title

• B60T13/686

  in hydraulic systems or parts thereof · CPC title