Braking system with two pressure sources, and method for operating a braking system with two pressure sources

Patent metadata

Field	Value
Publication number	US-11999326-B2
Application number	US-201917054672-A
Country	US
Kind code	B2
Filing date	May 15, 2019
Priority date	May 24, 2018
Publication date	Jun 4, 2024
Grant date	Jun 4, 2024

Abstract

A braking system including four hydraulically actuatable wheel brakes. A normally closed outlet valve is assigned to each wheel brake and a normally open inlet valve is assigned to each wheel brake. Two pressure supply devices are provided for active pressure build-up in the wheel brakes. A first and a second brake circuit are hydraulically configured with two wheel brakes respectively, wherein in each brake circuit a respective pressure supply device is hydraulically connected to two wheel brakes. A first and a second control and regulating unit are provided, wherein the first control and regulating unit electrically controls the pressure supply device of the first brake circuit, and wherein the second control and regulating unit hydraulically controls the pressure supply device of the second brake circuit, and the two control and regulating units are connected together via a data interface.

First claim

The invention claimed is:

1. A braking system comprising four hydraulically actuatable wheel brakes, wherein one normally closed outlet valve is assigned to each wheel brake and one normally open inlet valve is assigned to each wheel brake, wherein two pressure supply devices are provided for active pressure build-up in the wheel brakes, wherein a first brake circuit and a second brake circuit are hydraulically configured with two wheel brakes of the four hydraulically actuatable wheel brakes, respectively, wherein a first pressure supply device is hydraulically connected to the two wheel brakes of the first brake circuit and a second pressure supply device is hydraulically connected to the two wheel brakes of the second brake circuit, wherein a first and a second control and regulating unit are provided, wherein the first control and regulating unit electrically controls the pressure supply device of the first brake circuit, and wherein the second control and regulating unit electrically controls the pressure supply device of the second brake circuit, wherein the two control and regulating units are connected together via a data interface, and wherein the two brake circuits are connected in hydraulically isolatable fashion by way of two normally closed circuit switch-on valves, wherein a first normally closed circuit switch-on valve of two normally closed circuit switch-on valves is configured to be controlled by the first control and regulating unit, and wherein a second normally closed circuit switch-on valve of the two normally closed circuit switch-on valves is configured to be controlled by the second control and regulating unit, and wherein precisely one normally closed outlet valve of the normally closed outlet valves in the second brake circuit is configured to be controlled by the first control and regulating unit, and wherein precisely one normally closed outlet valve of the normally closed outlet valves in the first brake circuit is configured to be controlled by the second control and regulating unit.

2. The braking system as claimed in claim 1 , wherein a pedal feel simulator is provided.

3. The braking system as claimed in claim 2 , wherein the pedal feel simulator can be actuated by a brake pedal.

4. The braking system as claimed in claim 3 , wherein the brake pedal is coupled by a coupling rod to an axially movable simulator piston, and wherein two redundantly designed travel sensors are provided which measure the piston travel and/or pedal travel respectively.

5. The braking system as claimed in claim 4 , wherein a first of the two travel sensors is connected to the first control and regulating unit on the signal input side, and wherein a second of the two travel sensors is connected to the second control and regulating unit on a signal input side.

6. The braking system as claimed in claim 1 , wherein the two pressure supply devices are configured as linear actuators.

7. The braking system as claimed in claim 1 , wherein one pressure supply device of the two pressure supply devices is configured as a linear actuator, and wherein the other pressure supply device of the two pressure supply devices is formed as a pump.

8. The braking system as claimed claim 1 , wherein two separate on-board networks are provided, and wherein each pressure supply device of the two pressure supply devices is powered by a respective one of the two on-board networks.

9. The braking system as claimed in claim 1 , wherein the wheel brakes are hydraulically divided between the two brake circuits by axle.

10. The braking system as claimed in claim 1 , wherein a master brake cylinder is connected to the wheel brakes in hydraulically isolatable fashion.

11. A method for operating the braking system as claimed in claim 1 , wherein the two normally closed circuit switch-on valves are arranged in a hydraulic path between the first brake circuit and the second brake circuit and wherein on electrical failure of one brake circuit of the first brake circuit and the second brake circuit, in a failed brake circuit a pressure is controlled by actuation of one of the two normally closed circuit switch-on valves and an outlet valve of the at least one normally closed outlet valve in the first brake circuit or in the second brake circuit by the control and regulating unit in an electrically intact brake circuit, and wherein the pressure in the electrically intact brake circuit is controlled by two inlet valves of the at least one normally open inlet valve and one outlet valve of the at least one normally closed outlet valve in the first brake circuit or in the second brake circuit.

12. The method as claimed in claim 11 , wherein to build up pressure in the failed brake circuit, a pre-pressure is built up by an intact pressure supply unit in the electrically intact brake circuit, and wherein one of the two normally closed circuit switch-on valves is opened so that brake fluid flows into the failed brake circuit.

13. The method as claimed in claim 11 , wherein to dissipate pressure in the failed brake circuit, an outlet valve of the at least one normally closed outlet valve in the failed brake circuit is opened by an intact control and regulating unit.

14. The method as claimed in claim 11 , wherein to build up pressure in the intact brake circuit, brake fluid from a pressure chamber of the pressure supply device is conducted through the at least one inlet valve into one wheel brake of the two wheel brakes.

15. The method as claimed in claim 11 , wherein to dissipate pressure in the intact brake circuit, an outlet valve of the at least one normally closed outlet valve in the first brake circuit or in the second brake circuit is actuated by the control and regulating unit of the intact brake circuit, and wherein the inlet valve is opened of the wheel brake, to which an intact outlet valve is assigned.

16. The method as claimed in claim 15 , wherein in addition, the inlet valve of the wheel brake is opened which is assigned to the wheel brake of the two wheel brakes with a failed outlet valve.

17. The method as claimed in claim 15 , wherein at least one pressure supply device of the two pressure supply devices is configured as a linear actuator and wherein an actuator piston position is maintained during pressure dissipation.

Assignees

• Continental Teves Ag & Co Ohg

Inventors

• Besier Marco
• Drumm Stefan

Classifications

• B60T13/58 Primary

  Combined or convertible systems · CPC title

• B60T8/17

  Using electrical or electronic regulation means to control braking {(detecting or indicating faulty operation B60T8/885)} · CPC title

• B60T15/028

  in hydraulic systems · CPC title

• B60T7/042

  by electrical means, e.g. using travel or force sensors · CPC title

• B60T8/4081 Primary

  Systems with stroke simulating devices for driver input (B60T8/4077 takes precedence) · CPC title