Abstract: A pneumatic system includes a pneumatic motor, which may take the form of a vibrationless paving breaker utilizing a blow-striking member or hammer that is propelled to and from its force-transmitting or blow-striking position by a compressed gas. A valving arrangement provides for relatively large-ratio expansion of the compressed gas in the space under the hammer between its infeed thereinto and its exhaustion therefrom, in order to significantly utilize heat energy in the compressed gas to assist in energizing the propulsion of the hammer. Such heat energy is usually invested in the compressed gas by and during substantially adiabatic compression thereof at a gas-volume transformer, or compressor, included in the pneumatic system. It may be noted that the process of substantially adiabatic compression in the compressor is to a significant degree reversely duplicated in energizing the propulsion of the hammer.

Abstract: A cylindrical shell with a double acting piston, having a high pressure area and a low pressure area on each side thereof, is provided with a valve for alternately injecting high pressure gas to each small area to provide an initial piston drive, and valving for injecting gas under the pressure, opposite from the first high pressure end to the opposite larger area providing a secondary piston drive using expansion of the high pressure expanded gas from the opposite end of the piston. In reversing the piston, the opposite end becomes the drive end in the same manner. In one form, a two position slide valve, initially actuated by piston movement and completed by gas pressure movement, provides a transfer means for gas streams internally of the motor and for exhaust of the secondary expanded gas. The valve is arranged for an initial mechanical movement from one position toward the other position by contact with the end wall of the low pressure cylinder and then completely moved to other position by gas pressure.

Abstract: A method of and device for delivering measured quantities of liquid into a fluid in which a pressure differential is created in a fluid flow line and fluid is passed from the higher pressure side to a positive displacement fluid pump and returned therefrom to the lower pressure side and including a positive displacement liquid pump actuated from the fluid pump which feeds liquid to the fluid pump to mingle with the fluid passing back to the fluid flow line.

Abstract: A new control system is provided for a reciprocating fluid stroke motor of the type which is pressured at its rod end, reciprocation being achieved by intermittent exposure of its full blind-end face to the pressure fluid to overcome the pressure applied to its smaller rod-end face. The control means includes a valve for a passage through the piston, with adjustably-positioned trip-stops for shifting the valve between open and closed positions. The valve is biased to snap fully open when the piston movement toward its opening-stop opens it slightly and remain open until striking the closing-stop. Monostable or bistable trip-switch types of biasing means may be used, and unless one holding the valve closed with no fluid pressure is chosen, resumption of pressure supply after discontinuance will cause an initial retraction of the piston to its starting position, allowing time for the controlled apparatus to attain acceptable speed.

Abstract: A downhole, hydraulically actuated pump assembly, having an engine reciprocatingly connected to a production pump. Power fluid is conducted downhole to the engine of the pump assembly, while production fluid and spent power fluid is conducted uphole to the surface of the ground.The pump assembly includes a housing within which spaced, axially aligned, cylindrical chambers reciprocatingly receive spaced engine and pump pistons which are connected together in a manner to enable the engine to reciprocate the production pump.A mechanically actuated valve assembly is contained within the engine piston and is arranged respective to various different flow passageways so that flow of power fluid through the engine forces the engine piston to reciprocate.The valve assembly includes a control rod and a valve element concentrically arranged respective to one another and to the engine piston. The valve element is reciprocated respective to the engine piston in response to the reciprocation of the control rod.

Abstract: A positive displacement, reciprocating fluid flow meter produces a digital electrical output signal. The meter includes a piston which reciprocates within a cylinder for accurately measuring fuel flow rates over a wide range of rates. The device is particularly useful in measuring the rate of flow of fuel to an engine, and incorporates a valve for bypassing the piston to permit resetting of the meter at the end of each piston stroke.

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.

Abstract: As a drive in metal-cutting machines used for vibration cutting a hydraulic vibrator is proposed, which comprises a differential piston and a spring-balanced slide valve, which are made and arranged so as to ensure reciprocal successive communication between a pressurized chamber and discharge and inlet chambers. In said vibrator the smaller diameter d and the larger diameter D of said piston are in a relation of d = .sqroot.D.sup.2 /2, and as a result the piston reciprocates symmetrically with an equal speed in either directions. There is also provided a plurality of compensating chambers controlled by throttles of a variable section. Continuous regulation of the magnitude of the stroke of said differential piston is effected in the hydraulic vibrator over a large range.

Abstract: A fluid driven actuator for a neutron absorber in a nuclear reactor is of the piston and cylinder type. The actuator is located above the reactor core. Means are provided for alternately opening and closing a by-pass fluid flow path or passage through or across the piston within the cylinder. The flow path is closed when the piston and control rod is being raised and is subsequently opened to reduce flow resistance during insertion or scram. In the preferred embodiment, the piston is longitudinally movable relative to the piston or extension rod which connects with the neutron absorber. In one position of the piston, the by-pass path is open and in another position, it it closed.

Abstract: This invention relates to a hydraulic motor device comprising a cylinder and a piston reciprocating therein said piston being moved in one direction by means of a spring and in the other direction by means of fluid under pressure supplied against one side of the piston, said cylinder including an inlet for fluid at one end and an outlet for fluid at the other end, and said piston including an overflow aperture from one working side to the other, which aperture is controlled by a stop valve that is either completely open or completely closed depending upon its impact against two spaced apart points on the cylinder end walls.

Abstract: This invention relates to a linear hydraulic motor or actuator, more especially to a hydraulic motor in combination with a piston pump, serving to inject liquid fertilizers into a water pipe line.

Abstract: A device for injecting adjuvant into a liquid employing a stepped piston in a stepped cylinder with a valve in the piston triggered to open and close at opposite ends of the piston travel to cause a reversal of piston movement while a further piston integral with the first mentioned piston operates to pump metered quantities of adjuvant into the stepped cylinder.