Patent · US Expired

Solenoid valve

US4768555A · kind A · utility

10Cited by
2References
4Claims
0Family size

Assignee

Inventor

Key dates

Filing dateApr 30, 1987
Grant dateSep 6, 1988
Priority date
Expiry dateApr 30, 2007

Classification

  • Technology area (CPC Y)Emerging Cross-Sectional Technologies
  • CPC primaryY10T137/87225
  • WIPO fieldMechanical elements
  • WIPO sectorMechanical engineering

Abstract

A two way closed-center solenoid valve provides effective areas upon the valve members which result in static pressure balancing of these members. Additional feedback areas are provided and exposed to fluid pressure which approximates a first time derivative of fluid pressure at an outlet port of the solenoid valve. Accordingly, an input signal is opposed dynamically approximately as a first time derivative of fluid pressure delivered to the output port. The feedback areas are larger in effective area than the effective areas upon the valve members to provide a favorable margin of feedback forces over static and dynamic frictions.

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