Linear action fluid motor - has piston screwed onto rod with threads formed to compensate for manufacture tolerance

摘要

A linear fluid motor comprises a cylinder member, a piston of circular cross section being movable reciprocally within the cylinder in sealing relation with it. A piston rod is secured to the piston by a screw connection, the two sets of threads being proportioned and dimensioned to allow pivotal movement of the piston rod relative to the piston during reciprocation through a pivot angle sufficient to exceed a predetermined crookedness angle between the piston and rod. A retainer is located in mating grooves in the piston and the rod for preventing unscrewing movement of the piston on the rod.