Abstract: An air driven double diaphragm pump has two opposed pumping cavities with diaphragms extending thereacross. A shaft extends between the diaphragms and through an actuator housing. The housing includes a control valve assembly having a control valve to direct pressurized air to one or the other of the dual pumping cavities and two relief valves which cooperate with the pump shaft position to release air from one end or the other of the control valve for the shifting thereof. Shuttle valve elements are positioned between the control valve and the pumping chambers. The shuttle valve elements are slidably positioned within the valve cavities to move between extreme positions under the pressures within the input and the pumping cavity. In one extreme position, the pumping cavity is in communication with an exhaust having a tapered passage. In the other, the exhaust is cut off and pressurized air is able to pass through a one-way valve in a passageway through the shuttle valve element to charge the pumping chamber.

Abstract: An air driven double diaphragm pump has two opposed pumping cavities with diaphragms extending thereacross. A shaft extends between the diaphragms and through an actuator housing. The housing includes a control valve assembly having a control valve to direct pressurized air to one or the other of the dual pumping cavities and two relief valves which cooperate with the pump shaft position to release air from one end or the other of the control valve for the shifting thereof. Shuttle valve elements are positioned between the control valve and the pumping chambers. The shuttle valve elements are slidably positioned within the valve cavities to move between extreme positions under the pressures within the input and the pumping cavity. In one extreme position, the pumping cavity is in communication with an exhaust having a tapered passage. In the other, the exhaust is cut off and pressurized air is able to pass through a one-way valve in a passageway through the shuttle valve element to charge the pumping chamber.

Abstract: A hydraulic drive (10) for the adjustment, feed and return movements of a tool head of a machine tool comprises a hydraulic motor (11) and an after-running adjustment valve (12). The reference value of the position is set and the actual value indicated by means of a threaded spindle (39) and spindle nut (37) in the form of a hollow shaft. One of these two elements can be driven by an electric motor (41) in order to set the reference value of the position. The other of these two elements can be driven in order to indicate the value of the actual position. A rotational and angular position indicator system (68, 74, 75 and 69, 77) produces an output which is a direct measure of the total number of revolutions executed by the preset reference value shaft and of the azimuthal position of the preset reference value shaft within each revolution. An electronic position sensor system (71, 78 and 71', 78'; 71") produces an output which is a measure of the contouring error S.

Abstract: An electromagnetically operated mechanism produces an unstable first controlled pressure which, under a given condition, is saturated quickly to a degree slightly lower than a target value determined in accordance with an information signal issued from a brake pedal force detecting device. A servo-motor type actuator produces a stable second controlled pressure which, under a given condition, is saturated slowly to the target value. A control mechanism applies only the first controlled pressure to a work chamber of a pneumatic brake booster when the first controlled pressure is higher than the second controlled pressure, and applies only the second controlled pressure to the work chamber after the second controlled pressure becomes higher than the first controlled pressure.

Abstract: A low capital investment system for irrigating a relatively large area field, comprising a mobile base, and a sprinkler mounted on the base and adapted to accumulate water from a water supply and to intermittently discharge accumulated water in an irrigating stream over the field. Apparatus is provided for propelling the base in a back and forth movement traversing a field, and for generally reversing the water discharge direction each time the direction of travel is reversed. The sprinkler includes a novel, resiliently expandable reservoir construction for accumulating relatively large volume, intermittent bursts, and a drive system which also provides relatively short range, continual irrigation. Separate sprinkler units can be used on a field concurrently, or a single unit can be moved over successive areas of a field until the whole field has been covered.

Abstract: A hydraulically operated reciprocating piston and a differential force operated valve are both in continuous fluid contact with a pressurized cushion chamber as well as the piston chamber pressure. The valve position is a function of the cushion chamber pressure. The cushion chamber pressure is a function of the axial position of the piston. The values of these functions are such that the piston is reciprocated when the machine is operated. The valve is a sleeve coaxial with the piston.

Abstract: A hydraulically operated reciprocating piston and a differential force operated valve are both in continuous fluid contact with a pressurized cushion chamber as well as the piston chamber pressure. The valve position is a function of the cushion chamber pressure. The cushion chamber pressure is a function of the axial position of the piston. The values of these functions are such that the piston is reciprocated when the machine is operated. The valve may, for example, be a sleeve coaxial with the piston or a valve transversely spaced from the piston.

Abstract: In a fluid-flow pulsator, a housing has a chamber with an inlet and an outlet. Within the housing is a piston assembly having first and second pistons with the first having a working area less than that of the second. A valve associated with the assembly closes the outlet on movement of the assembly. The assembly is resiliently urged in a direction effecting closure of the outlet with the first and second pistons effectively being disposed in the chamber on opposite sides of the inlet. The introduced fluid pressure, the urging strength and the piston areas are correlated so as to produce pulses of fluid from the outlet in response to a supply of fluid to the inlet.

Abstract: A hauling device, for example for a mining machine, has two clamping elements which grip on ramps each of which elements is attached to an operating rod of a hauling jack. The jacks are operated alternately, in conjunction with the clamping elements to advance or retract the machine, and the hauling jacks are hydraulically interconnected in a manner to avoid hunting.