Patent · US Expired

Servovalve

US4624284A · kind A · utility

9Cited by
5References
3Claims
0Family size

Assignee

Inventor

Key dates

Filing dateJan 24, 1985
Grant dateNov 25, 1986
Priority date
Expiry dateJan 24, 2005

Classification

  • Technology area (CPC Y)Emerging Cross-Sectional Technologies
  • CPC primaryY10T403/32631
  • WIPO fieldMechanical elements
  • WIPO sectorMechanical engineering

Abstract

A servovalve includes a flow-control valve connectable between a source of fluid pressure and a load and having a spool displaceable between an open position permitting fluid flow between the load and the source and a closed position axially offset therefrom and blocking such flow. A pilot valve has an impact plate and a pair of nozzles operatively axially oppositely effective on the spool and oppositely flanking the plate. Thus when the plate is closer to one of the nozzles than to the other the spool is axially displaced into one of its positions and when the plate is closer to the other nozzle the spool is urged axially oppositely. A solenoid-type servomotor is connected to the impact plate to move same between the nozzles so that when it is close to one nozzle it blocks flow therefrom and allows pressure to build up on the corresponding end of the spool, while the other nozzle is opened to reduce pressure at the corresponding spool end. A feedback spring is attached to the impact plate, extends generally radially of the spool, and has a free end projecting into a recess formed in the spool. A force-transmitting ball is fixed to the free end of the spring and fitted in the reces…

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