Boosted braking device with emergency valve
US6773079B2 · kind B2 · utility
Assignee
Inventor
Key dates
| Filing date | Apr 4, 2002 |
| Grant date | Aug 10, 2004 |
| Priority date | — |
| Expiry date | Nov 15, 2022 |
Classification
- Technology area (CPC B)Performing Operations; Transporting
- CPC primaryB60T13/573
- WIPO fieldTransport
- WIPO sectorMechanical engineering
Abstract
A braking device, for a motor vehicle, comprising: a master cylinder (2), a primary piston (3) mounted to slide in the master cylinder, a manual-control member (4), a booster coupled to the manual-control member, an emergency assist valve (VA) comprising a reaction piston (17a) and a rapid piston (17b), and a ratio control (T) actuated by a plunger distributor (10) driven by the manual-control member (4). The reaction piston (17a) and the rapid piston (17b) form one and the same stepped piston (17) having a part (17a) of large cross section and a part (17b) of small cross section, the large-section part (17a) determining, with a first bore (18) of the primary piston (3), a variable-volume annular chamber (27). A separation/communication assembly (28, 29, 30), controlled by the displacement of the stepped piston (17), is designed so that the pressure of the liquid is exerted effectively on the large cross section (17a) of the stepped piston when the stepped piston occupies a position of rest or is to the rear of the position of rest, and on only the small cross section (17b) when the stepped piston is displaced forward relative to the main piston under emergency braking.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.