Parker-Hannifin Corporation
Return to neutral mechanism for hydrostatic transmission

Abstract:

A return-to-neutral mechanism for a hydrostatic transmission configured to return a control member of a pump to neutral after the control member has been moved toward a forward or reverse position. The return-to-neutral mechanism includes a stop member mountable to a housing, a control arm for moving the control member, and a spring for engaging the control arm and stop member to bias and return the control arm to neutral after being released from forward or reverse positions. The stop member may have an opening for receiving a fastener for mounting to the housing, and the opening may be configured to permit adjustment of the stop member along at least two transverse directions to preload the spring at the neutral position. The control arm may have abutments for moving legs of the spring, and the abutments may have recessed and protruding portions for receiving and containing the spring legs.