Rotary hydraulic machine having a valve responsive to rotor bore pressure and stator port pressure
US4048903A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Mar 15, 1976 |
| Grant date | Sep 20, 1977 |
| Priority date | — |
| Expiry date | Mar 15, 1996 |
Classification
- Technology area (CPC F)Mechanical Engineering; Lighting; Heating
- CPC primaryF04B1/2042
- WIPO fieldEngines, pumps, turbines
- WIPO sectorMechanical engineering
Abstract
A rotary hydraulic pump or motor has a piston-carrying rotor having a face engaging a port plate which includes a high pressure port. A number of by-pass passages enable the rotor bores to communicate with the high pressure port before being in full alignment therewith. A valve arrangement is responsive to the pressures in the high pressure port and in successive ones of the rotor bores to provide that variation of these pressures causes variation of the position, relative to top-dead-center, at which successive rotor bores communicate with the high pressure port via the by-pass passages. The arrangement is such that pressures in the rotor bores and the high pressure port, immediately before they communicate, are maintained substantially equal over a range of pressures.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.