Reciprocating hydraulic motor utilizing a ramped valve yoke with a tripping spring

Abstract

The ramped valve yoke is utilized in a hydraulic reciprocating motor. The uniqueness of this valve yoke is the profile of the surface on which a ball-detent mechanism rides. The profile ensures the ball-detent will always snap into a position on either end of the profile and prevents the ball-detent from stopping on the profile. This action ensures the switching valve of a hydraulic reciprocating motor will always be fully engaged in either one of two positions and will never stop half way between positions.

What is claimed is:  
     
         1 . In a hydraulic reciprocating motor having a piston, a spool sleeve moveable between first and second positions and at least two ports, the improvement comprising providing a tripping spring in conjunction with a ramped yoke to provide a reliable method of switching direction of said piston such that the tripping spring stores energy while the piston enjoys the full force provided by fully open said ports, and so that said ramped yoke prevents said spool sleeve from stopping half way between positions.