Patent · US Expired

Electro-hydraulic actuator or positioning drive for continuous control or regulation operations

US4648245A · kind A · utility

4Cited by
5References
10Claims
0Family size

Assignee

Inventor

Key dates

Filing dateApr 30, 1985
Grant dateMar 10, 1987
Priority date
Expiry dateApr 30, 2005

Classification

  • Technology area (CPC F)Mechanical Engineering; Lighting; Heating
  • CPC primaryF15B15/18
  • WIPO fieldMechanical elements
  • WIPO sectorMechanical engineering

Abstract

A piston sealed by a rolling membrane is arranged in a cylindrical housing comprising two components and this piston translates against the force of a return spring. A vibrating armature pump driven via two wires by a variable alternating voltage serves for operating the positioning drive. The vibrating armature pump draws hydraulic fluid from a reservoir chamber through an inlet opening and transports the hydraulic fluid through a return valve and through a first orifice into a pressure chamber. The piston is displaced downwardly conjointly with a piston rod. The pressure generated by the vibrating armature pump is dependent upon the applied voltage. A state of equilibrium between this pressure and the counterpressure of the spring arises such that the positioning drive is suitable for continuous control or regulation operations. The return valve comprises a membrane valve which decisively influences the intended working characteristics of the positioning drive, since it responds to small differences in pressure.

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