Patent · US Expired

Pilot valve operated pressure reducing valve

US4590968A · kind A · utility

14Cited by
6References
13Claims
0Family size

Assignee

Inventor

Key dates

Filing dateJun 18, 1984
Grant dateMay 27, 1986
Priority date
Expiry dateJun 18, 2004

Classification

  • Technology area (CPC Y)Emerging Cross-Sectional Technologies
  • CPC primaryY10T137/86614
  • WIPO fieldControl
  • WIPO sectorInstruments

Abstract

The invention refers to a pressure reducing valve including a pilot valve. The main piston of the pressure reducing valve allows to selectively connect a load port to either a port connected to a pressure source or to a port connected to the reservoir. The pilot valve is connected to a control pressure line and to the reservoir. The main piston controlled connection to the reservoir opens within the valve housing into a port connecting the pilot valve to the reservoir. This provides for a substantially simplified construction of the valve since there are only two operating ports and a reservoir port. Furthermore, the main piston is engaged by a spring which is capable of becoming activated such that dynamic stresses resulting from a change from high to low pressure values are avoided which vibrations are detrimental in generating pressure peaks as well as pressure breaks.

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