Abstract: A shuttle valve mounted between a pneumatic piston and a ring plate in a reciprocating pneumatic motor and moved to control the passage between a shuttle compression chamber and a radial air inlet hole in the pneumatic piston, the shuttle valve having a press rod supported on a compression spring and forced out of the front end of the body of the shuttle valve for pressing against the cylinder cover of the reciprocating pneumatic motor, enabling the shuttle valve to shut off automatically at an early stage so as to extend the piston stroke when the pneumatic piston bears the load, or to shorten the piston stroke when the pneumatic piston bears no load.

Abstract: A pressure medium operated device generating to-and-fro motion to one or several pistons or a similar motion transmitting arm. The device includes a primary piston to which motion is brought in transmitting pressure medium alternately to both sides of the piston and control valves located inside the primary piston for controlling the pressure medium which moves the primary piston.

Abstract: A liquid additive injection pump has a hydraulic motor comprising a differential piston assembly reciprocable in a housing under the urging of a primary liquid into which an additive is to be injected. The piston assembly carries valves which are responsive to movement of the piston assembly to open and close to effect the transfer of a primary fluid charge from the pump motor to a discharge passage and to effect reciprocation of the piston assembly. The motor piston is connected to a central axially disposed longitudinally extending piston rod which extends into an additive injection pump cylinder and engages a floating additive injection pump piston having a stack of additive pump displacement control washers engaged therewith and disposed on the piston rod. A spring biased toggle type linkage snaps the motor valves into open and closed positions to provide positive movement of the valve members.

Abstract: A fluid pressure actuated system for axially reciprocating an element while the element is being driven in rotation. A piston is mounted within a piston chamber in a rotary shaft. The rod side of the piston head is continuously exposed to fluid under pressure supplied by a pump. A pilot valve is mounted in a chamber within the piston and is axially movable relative to the piston between opposite end limits. The valve cooperates with a ported sleeve which defines the valve chamber to apply pressure from the pump to the valve in a manner which shifts the valve from one of its end limits to the other each time the piston arrives at an end of its stroke. Shifting of the valve in turn controls the supply of fluid under pressure to the piston to cause reversal of the piston stroke. Both piston and valve are biased in one direction by fluid pressure at all times, movement of the piston and valve against the biasing pressure being accomplished by applying an overcoming fluid pressure in the opposite direction.

Abstract: A hand-operated pneumatic impact machine comprising a hollow body with an axially-reciprocating impact ram inside which forms, together with the body, variable-volume working chambers. It also comprises a distributing space communicating with the working chambers and with a source of compressed air. There also is a valve in the form of a cylindrical bushing whose inner surface covers at least one hole which admits compressed air into the distributing space, the compressed air forcing the valve to cover alternately the inlet channels of the working chambers for reciprocating the impact ram. The valve has at least one longitudinal channel which is in constant communication with the source of compressed air through a hole which connects the distributing space with the source of compressed air, the channel being intended to deliver compressed air to the inlet channels of the working chambers.

Abstract: An improved fluid motor having only two moving components, a reciprocatable piston and a fluid actuated valve spool. The piston is supported for linear movement in a piston support bore of a barrel assembly, and is moved in alternating directions by the operation of selected porting of a pressure fluid selectively admitted against differential piston pressure faces. The valve spool is disposed in an inner bore in the piston and is alternately driven in opposing directions by automatically controlled and selective application of fluid pressure. The fluid motor experiences no mechanical impact between the valve spool and the piston.