Patent · US Expired

Rotary hydraulic machine

US4175472A · kind A · utility

5Cited by
1References
4Claims
0Family size

Assignee

Inventor

Key dates

Filing dateDec 9, 1977
Grant dateNov 27, 1979
Priority date
Expiry dateDec 9, 1997

Classification

  • Technology area (CPC F)Mechanical Engineering; Lighting; Heating
  • CPC primaryF04B1/2021
  • 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 valve arrangement is responsive to the pressures in the high pressure port and in successive ones of the rotor bores to provide that variation in these pressures causes variation of the position, relative to top-dead-center, at which successive rotor bores communicate with the high pressure port through by-pass passages, and thereby substantially equalize the pressures in the bores and the high pressure port. The port plate and rotor also include passages by which the pressures in the rotor bores can be increased rapidly after their respective top-dead-center positions.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.