Steering power-assistance arrangement
US4770612A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Jul 6, 1987 |
| Grant date | Sep 13, 1988 |
| Priority date | — |
| Expiry date | Jul 6, 2007 |
Classification
- Technology area (CPC F)Mechanical Engineering; Lighting; Heating
- CPC primaryF01C21/10
- WIPO fieldEngines, pumps, turbines
- WIPO sectorMechanical engineering
Abstract
A steering power-assistance pump of vane type includes a combined flow control and pressure relief valve. When the steering valve of the steering arrangement shuts off the flow of oil, the output of the pump is converted into heat within the pump which accordingly suffers a substantial rise in temperature. The rotor of the pump and the cam ring with which the rotor vanes co-operate are combined with a pressure plate and a wear plate on respective sides of the rotor to form a unit which is displaceable in the axial direction of the pump against the force of a compressible sealing means for sealing off inlet ducts relative to a pressure chamber behind the pressure plate. The unit is thus displaced against the force of the compressible sealing means, as a result of thermally induced deformation of the housing portions of the pump. The wear and pressure plates have coatings of bearing metal on their surfaces which co-operate with the rotor, to provide better anti-friction properties.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.