Auxiliary coupler pressure relief hydraulic system with pump drive ignition switch relief
US4881371A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jul 26, 1988 |
| Grant date | Nov 21, 1989 |
| Priority date | — |
| Expiry date | Jul 26, 2008 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10S60/911
- WIPO fieldTransport
- WIPO sectorMechanical engineering
Abstract
An auxiliary coupler pressure relief hydraulic system for off-road vehicles including a battery, an engine, an engine ignition system, a reservoir of hydraulic fluid, and a pump for providing hydraulic fluid under pressure. Quick couplers couple hydraulic fluid to an attachment mounted to the vehicle. An electro-hydraulic spool valve is connected to a source of pilot pressure and controls the flow of hydraulic fluid to the quick couplers in response to valve actuating signals. Forward and reverse auxiliary control switches are coupled to the spool valve and provide valve actuating signals resulting in fluid flow to the quick couplers in forward and reverse directions. Also included is an ignition switch having RUN, OFF and RELIEF positions. When switched from its RUN position to its RELIEF position, the ignition switch provides pressure relief valve actuating signals which stroke the spool valve and bleed pressure trapped between the valve and the quick couplers while the engine RPM is decreasing and pilot pressure is still available.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.