Abstract: The invention is therefore directed to a rotary valve actuating system coupled to a pipeline for a pressurized fluid, the actuating system being coupled to the rotary valve to selectively cause operation of the valve. The valve actuating system comprises at least two reservoirs having an amount of an operating liquid in a first portion being coupled to an external source of pressurized fluid in a second portion thereof. A slideable piston is positioned within each of the reservoirs to isolate the first and second portions, and upon application of pressure from the external pressurized fluid against the slideable piston, operating liquid is supplied to actuate the rotary valve. In this manner, the operating liquid is isolated from the external source of pressurized fluid, such as supplied from the pipeline.

Abstract: The invention is therefore directed to a rotary valve actuating system coupled to a pipeline for a pressurized fluid, the actuating system being coupled to the rotary valve to selectively cause operation of the valve. The valve actuating system comprises at least two reservoirs having an amount of an operating liquid in a first portion being coupled to an external source of pressurized fluid in a second portion thereof. A slideable piston is positioned within each of the reservoirs to isolate the first and second portions, and upon application of pressure from the external pressurized fluid against the slideable piston, operating liquid is supplied to actuate the rotary valve. In this manner, the operating liquid is isolated from the external source of pressurized fluid, such as supplied from the pipeline.

Abstract: A rotary actuator of the rack and pinion type having a two-piece rack and piston assembly. This rack and piston assembly comprises a rack insert and a one-piece piston member, which includes a piston at each end, a connecting strut extending from one piston to the other and means for retaining the rack insert in such manner that the rack is free to float in any direction except longitudinally but is constrained from longitudinal movement.

Abstract: A rotary actuator having a piston travel adjustment mechanism and a cushioning mechanism associated in a single attached unit, with side porting for fluid pressure, thus having a more compact structure that is lighter in weight and yet completely adjustable.

Abstract: Rotary actuator of the rack and pinion type. The rotary actuator has a rack with a generally cylindrical outer surface having a recess which receives a rack bearing and an arcuate rack bearing which is received in that recess. The rack bearing has an arcuate, convex outer bearing surface and an arcuate concave inner surface which abuts the rack and the rack has a recessed outer surface which conforms in shape to the inner surface of the rack bearing. The rotary actuator may have two racks as shown. The rotary actuator has a pair of floating pistons associated with each rack.

Abstract: A drive ring for a rotary expansible chamber hydraulic motor has driving gear teeth on its inner periphery and is constrained against other than planetating motion by a series of angularly spaced eccentric bearings rotatably mounted in fixed port plates between which the drive ring is sandwiched. The eccentric bearings are hydorstatically balanced against peak loads with high pressure fluid. Vanes sliding in radial slots in the drive ring are maintained in engagement against a surrounding cylindrical chamber wall by leaf springs whose opposite ends slide in grooves in the port plates.

Abstract: A fluid-operated actuator for rotatable valve stems and the like includes a double ended piston reciprocally carried in a sealed housing. The housing has a pair of sleeves threaded into a central body. The sleeves support opposite end regions of the piston and provide adjustable stops to limit the piston stroke. A stem is journaled for rotation in the body. The stem and piston are interconnected by a lever slidably received in the stem and pivotally coupled to the piston. The lever rotates the stem in response to reciprocation of the piston. The sliding connection between the lever and the stem provides a thrust connection between the lever and the stem and permits the lever-arm through which torque forces are applied to the stem to increase as the piston nears opposite ends of its stroke. An adapter bushing is removably connected to one end region of the stem.