Patent attributes
A spool valve includes a housing having a spring-enclosing portion and a spool-enclosing portion aligned along a longitudinal axis. A spool is mounted for reciprocal axial movement in the housing and a piston is fixed to one end of the spool. The spool-enclosing portion supports a stationary bushing having a bore receiving an opposite control end of the spool, the bushing formed with a first plurality of radially-oriented passages opening into an annular groove formed in the bore, the groove having sloped side edges. The spool supports plural ring-seals arranged to engage the sloped side edges of the annular groove and thereby seal off the radially-oriented passages when the spool is in a neutral position. Movement of the spool is adjustably limited in one direction and dampened in both axial directions.
