Brake system for motor vehicles

Patent metadata

Field	Value
Publication number	US-9834188-B2
Application number	US-201415036579-A
Country	US
Kind code	B2
Filing date	Nov 13, 2014
Priority date	Nov 21, 2013
Publication date	Dec 5, 2017
Grant date	Dec 5, 2017

Abstract

A hydraulic brake system includes a brake actuating element, a simulation device with a detector for detecting brake actuation by a driver. No mechanical and/or hydraulic operative connection between the brake actuating element and the wheel brakes is provided. A pressure medium reservoir, an electrically controllable pressure source for actuating the wheel brakes can be connected to each of the wheel brakes, electrically actuable wheel valves assigned to the wheel brakes for setting wheel brake pressures, and at least one electronic control and regulating unit for actuating the pressure source and wheel valves. The pressure source includes at least one piston which is sealed in a housing by a first sealing element and a second sealing element. In the case of a leak of the first sealing element, a pressure build-up is carried out at the wheel brakes by the pressure source with use of the second sealing element.

First claim

The invention claimed is:

1. A brake system for motor vehicles with a plurality of hydraulically actuated wheel brakes, the system comprising:
a brake actuating element,
a simulation device that works in conjunction with the brake actuating element with means for detecting a brake actuation by a driver of the vehicle, wherein the brake actuating element lacks any mechanical or hydraulic operative connection with any of the wheel brakes in any braking mode of the brake system,
a pressure medium reservoir container at atmospheric pressure,
an electrically controlled pressure source for actuation of the wheel brakes, which is or can be connected to each of the wheel brakes,
electrically actuated wheel valves associated with the wheel brakes for adjusting wheel brake pressures, and
at least one electronic control and regulation unit for actuating the pressure source and wheel valves,
wherein the pressure source comprises at least one first piston that can be actuated by an electric motor and is displaceably guided in a housing, the housing defining a pressure chamber that is sealed by a first sealing element in a first position of the at least one first piston, wherein the pressure source comprises a second sealing element which is configured to seal the pressure chamber in a second position of the at least one first piston, the second sealing element implemented such that in the event of a leak in the first sealing element a pressure build-up at the wheel brakes is carried out by the pressure source using the second sealing element.

2. The brake system as claimed in claim 1 , wherein the second sealing element has no sealing effect if the first piston is in a non-actuated state.

3. The brake system as claimed in claim 2 , wherein the pressure source comprises a first cylinder-piston arrangement with the first piston and the first sealing element and a second cylinder-piston arrangement with a second piston and the second sealing element, wherein the first and the second piston can be actuated by the electric motor, and wherein the pressure ports of the cylinder-piston arrangements are connected to each other and are or can be connected to each of the wheel brakes.

4. The brake system as claimed in 2 , wherein the pressure source comprises a pressure chamber bounded by the first piston and the housing, which pressure chamber is or can be connected to each of the wheel brakes, wherein the pressure chamber can be sealed by the first and/or the second sealing element.

5. The brake system as claimed in claim 1 , wherein the pressure source comprises a pressure chamber bounded by the first piston and the housing, which pressure chamber is or can be connected to each of the wheel brakes, wherein the pressure chamber can be sealed by the first and/or the second sealing element.

6. The brake system as claimed in claim 5 , wherein the pressure chamber is sealed by the first sealing element in a non-actuated state of the first piston and the second sealing element provides a seal following a predetermined actuation of the first piston.

7. The brake system as claimed in claim 5 , wherein the pressure source comprises a stepped bore that is disposed in the housing and the first piston is in the form of a stepped piston, a smaller diameter piston stage of which, following a predetermined actuation of the stepped piston, divides the pressure chamber into a first pressure chamber that is sealed by the second sealing element and a second pressure chamber.

8. The brake system as claimed in claim 1 , wherein the brake system comprises an electrically actuated parking brake system that comprises an electromechanically actuated brake actuator on each of at least two wheel brakes, wherein the parking brake system can be actuated by the control and regulation unit.

9. The brake system as claimed in claim 8 , wherein the control and regulation unit comprises means with which braking is performed by means of the parking brake system in the event of a mechanical fault of the pressure source.

10. The brake system as claimed in claim 1 , wherein the control and regulation unit are implemented such that a pressure build-up by the pressure source continues to be possible in the event of a single electrical fault in the pressure source.

11. The brake system as claimed in claim 1 , wherein each of the wheel brakes is connected to the pressure medium reservoir container for the purposes of pressure equalization when the brake system is in a deenergized state.

12. The brake system as claimed in claim 1 , wherein the pressure source comprises a first cylinder-piston arrangement with the first piston and the first sealing element and a second cylinder-piston arrangement with a second piston and the second sealing element, wherein the first and the second piston can be actuated by the electric motor, and wherein the pressure ports of the cylinder-piston arrangements are connected to each other and are or can be connected to each of the wheel brakes.

13. The brake system as claimed in claim 1 , wherein the pressure source and the wheel valves, and the control and regulation unit, are disposed in a pressure modulation device that is spatially separate from the simulation device.

14. The brake system as claimed in claim 1 , wherein means for actuating the electric motor, as well as the windings of the electric motor, are implemented such that a pressure build-up by the pressure source continues to be possible in the event of a single electrical fault in the pressure source.

Assignees

• Continental Teves Ag & Co Ohg

Inventors

• Feigel Hans-Jörg

Classifications

• B60T8/4018

  Pump units characterised by their drive mechanisms (B60T8/4095 takes precedence) · CPC title

• B60T8/4081

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

• B60T8/326 Primary

  Hydraulic systems · CPC title

• B60T8/4031

  Pump units characterised by their construction or mounting (pump units in combination with valve blocks B60T8/36) · CPC title

• B60T2270/82

  Brake-by-Wire, EHB · CPC title