Patent · US Expired

Graduated release valve

US6227521A · kind A · utility

5Cited by
8References
13Claims
0Family size

Assignee

Inventors

Key dates

Filing dateDec 30, 1999
Grant dateMay 8, 2001
Priority date
Expiry dateDec 30, 2019

Classification

  • Technology area (CPC B)Performing Operations; Transporting
  • CPC primaryB60T15/54
  • WIPO fieldTransport
  • WIPO sectorMechanical engineering

Abstract

An apparatus incrementally reduces pressure in a first volume in response to an increase in pressure in a second volume. A valve body defines a bore that houses a piston and supply and return passages that communicate with first and second ends of the bore, respectively. The valve body also defines a release passage that connects the bore with the first volume and an exhaust passage that connects the bore with atmosphere. An inlet valve opens when pressure in the second volume increases relative to pressure in the supply passage. An outlet valve opens when pressure in the second volume decreases relative to pressure in the return passage. The piston is biased in a closed position against the first end and defines a passageway through which the first and the second ends communicate. When pressure increases in the second volume, the inlet valve opens causing the first end to pressurize and move the piston to an open position in which the release and exhaust passages communicate. This allows the first volume to vent gradually to atmosphere. As the pressure gradually equalizes between the first and second ends via the passageway, the piston returns to its closed position thereby discon…

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