Patent · US Expired

Control apparatus for an adjustable hydraulic machine driven by an adjustable driving motor

US3932993A · kind A · utility

44Cited by
3References
3Claims
0Family size

Assignee

Inventor

Key dates

Filing dateDec 11, 1974
Grant dateJan 20, 1976
Priority date
Expiry dateDec 11, 1994

Classification

  • Technology area (CPC F)Mechanical Engineering; Lighting; Heating
  • CPC primaryF16H61/465
  • WIPO fieldMechanical elements
  • WIPO sectorMechanical engineering

Abstract

Apparatus for adjusting a hydraulic machine driven by an adjustable driving motor comprises an adjustment motor which adjusts the machine in one sense under one fluid control input dependent upon actual driving motor speed and in an opposite sense under an opposing such input supplied at a control outlet of a pressure control valve device in dependence upon the position of a valve slide thereof urged by the first input against a biasing force selectively adjustable in dependence upon desired driving motor speed. When the actual speed falls sufficiently relative to the desired speed, the slide travels from one position, blocking flow from a fluid inlet of the valve device to its control outlet, to another position allowing such flow and also allowing the second input thus produced to act on the slide, in the same direction as the first does, until the slide returns to its initial position.

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