Actuation device for an electrohydraulic braking system
US6775979B1 · kind B1 · utility
Assignee
Inventors
Key dates
| Filing date | Apr 26, 2002 |
| Grant date | Aug 17, 2004 |
| Priority date | — |
| Expiry date | Feb 4, 2023 |
Classification
- Technology area (CPC B)Performing Operations; Transporting
- CPC primaryB60T13/686
- WIPO fieldTransport
- WIPO sectorMechanical engineering
Abstract
The present invention relates to an actuation device for an electrohydraulic brake system of the ‘brake-by-wire’ type which is configured as a tandem master cylinder with a first and a second piston that are respectively biased by a resetting spring in opposition to the actuating direction. The resetting spring associated with the first piston is additionally used as a travel simulator spring which determines the pedal characteristics, and a valve device is provided which closes or opens a hydraulic connection between a pressure chamber accommodating the travel simulator spring and a pressure fluid supply reservoir.To ensure that only a small lost travel must be covered in the event of failure of the independent brake force, the present invention discloses that the valve device is adapted to be closed by the movement of the second piston in relation to the housing of the tandem master cylinder, and is formed by a sealing sleeve arranged at the second piston and a channel that is designed in the area of movement of the sealing sleeve and connected to the pressure fluid supply reservoir.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.