Hydraulic brake release system
US4989703A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Nov 10, 1988 |
| Grant date | Feb 5, 1991 |
| Priority date | — |
| Expiry date | Nov 10, 2008 |
Classification
- Technology area (CPC B)Performing Operations; Transporting
- CPC primaryB60W2710/18
- WIPO fieldTransport
- WIPO sectorMechanical engineering
Abstract
An all-hydraulic brake release system is disclosed for use on a vehicle having a transmission fluid pressure source, a brake fluid pressure source and a spring-applied, fluid pressure-released vehicle brake. The system has a control valve block which is hydraulically connected to the transmission fluid pressure source, the brake fluid pressure source and the brake. A first, transmission clutch pressure-responsive valve in the block controls the fluid connection between the brake fluid pressure source and the vehicle brake. A second, brake fluid pressure-responsive valve in the block controls the communication of brake fluid pressure to a pilot end of the first valve. If either brake fluid pressure or transmission clutch pressure falls below respective predetermined values, the first valve closes to cut off the supply of brake fluid pressure to the brake such that the brake is applied to stop vehicle movement.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.