Patent · US Expired

Pressure isolated pilot check valve

US5666993A · kind A · utility

0Cited by
4References
11Claims
0Family size

Assignee

Inventors

Key dates

Filing dateMay 3, 1995
Grant dateSep 16, 1997
Priority date
Expiry dateMay 3, 2015

Classification

  • Technology area (CPC Y)Emerging Cross-Sectional Technologies
  • CPC primaryY10T137/7782
  • WIPO fieldMechanical elements
  • WIPO sectorMechanical engineering

Abstract

An improved check valve for selectively controlling the flow of fluid through a valve seat. A spring biases a plunger against the valve seat when the fluid is stationary. Movement of the fluid pushes the valve plunger against the spring to open the aperture of the valve seat. An actuator selectively exerts a force against the plunger to close the plunger against the valve seat. In one embodiment of the invention, the actuator directs a pressurized fluid against a second end of the plunger, and a seal prevents leakage of such fluid toward the plunger first end in contact with the valve seat. A cavity between the seal and the plunger first end can be vented to the atmosphere to maintain the pressure differential created by the pressurized fluid against the plunger second end.

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