Variable displacement pump
US7128542B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Dec 3, 2001 |
| Grant date | Oct 31, 2006 |
| Priority date | — |
| Expiry date | Aug 24, 2022 |
Classification
- Technology area (CPC F)Mechanical Engineering; Lighting; Heating
- CPC primaryF04C14/226
- WIPO fieldEngines, pumps, turbines
- WIPO sectorMechanical engineering
Abstract
In a hydraulic pump, a cam ring is provided in a cylindrical adaptor for movement in a radial direction, and a differential pressure control valve is provided to control internal pressure and load pressure at the front and back sides of a variable orifice to be introduced into action chambers and formed at the opposite sides of the cam ring for controlling a discharge amount of the pump in accordance with the rotation speed of the pump. The differential pressure control valve is operated under the internal pressure and load pressure respectively introduced into action chambers and the load of a thrust spring biasing the differential pressure control valve toward the internal pressure chamber. The load of the thrust spring is increased or decreased in accordance with an increase or a decrease of the load pressure. The increase or decrease of the load pressure is effected by a load pressure responsive piston loaded by a thrust spring and engaged with the differential pressure control valve at one end thereof in the internal pressure chamber.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.