Abstract: A control valve unit (10) disclosed includes a slide mechanism (14) mounted on a base (40) of the unit, a control member (18) driven by a hydraulic linear actuator (12) controlled by the unit, and a control valve (22) that feeds hydraulic fluid to the actuator and has a deactivator (24) that is engaged and moved by a pair of slides (16a,b) of the slide mechanism under the impetus of the control member movement in order to terminate driving of the actuator at its limits of movement. The slide mechanism includes a slideway on the base and a pair of fixed stops (62a,b) between which the movable slides are supported on the slideway and biased by a helical spring (68) against the stops. The helical spring is aligned with openings (66) in the slides and the control member (18) extends through the spring and the slide openings. Lugs (76a,b) on the control member for moving the slides are preferably adjustable so as to permit adjustment of the limits of actuator movement.

Abstract: A worm gear set (12) particularly adapted for use as a valve actuator (10) includes a stop mechanism (14) having a blocking member (32) and a stop (34) that cooperate to terminate rotation of the worm (18) thereof in order to limit the extent of rotation of the gear (22) driven by the worm while preventing lockup due to excessive torque applied to the worm. An actuator (36) on the gear preferably moves the blocking member from a nonblocking position to a blocking position as the gear approaches an extreme of rotary movement whereupon the stop which is mounted on the worm is engaged by further worm rotation with the blocking member to terminate worm rotation and thereby limit the extent of gear rotation.

Abstract: A seal assembly utilizing a floating seat principle in a fluid powered rotary actuator to seal the arcuate surfaces and the planar ends of the actuator. The seal incorporates a two piece retainer design with a peripheral O-ring and cap ring combining with a captured O-ring and shoulder bolt which give the additional sealing and floating principle to assure effective sealing of the pressure chambers.

Abstract: A mechanical feedback controlled valve regulates the fluid flow into the vane or piston compartment for controlling the direction, position, velocity, acceleration and/or deceleration of the output shaft.