Hydraulic ratio-changing booster with hydraulic lock
US4237772A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Feb 22, 1979 |
| Grant date | Dec 9, 1980 |
| Priority date | — |
| Expiry date | Feb 22, 1999 |
Classification
- Technology area (CPC B)Performing Operations; Transporting
- CPC primaryB60T13/144
- WIPO fieldTransport
- WIPO sectorMechanical engineering
Abstract
A hydraulic power booster system in which a hydraulic power brake booster has hydraulic ratio changing mechanisms. The ratio is established by trapping hydraulic fluid in a chamber with an input piston having a larger effective area than an output piston forming movable chamber walls. A ratio piston or sleeve exposed to booster power pressure and the trapped pressure is moved upon power runout, causing the booster ratio to change as the ratio of these pressures changes, providing a smooth transition from a high ratio toward a 1:1 ratio as the booster shifts to manual operation from hydraulic power operation. A trapped hydraulic fluid link is established between the input piston and the booster output member for manual operation. These are two booster modifications shown.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.