Abstract: A hydraulic or pneumatic actuator wherein the movement of the power transfer shaft is controlled by a movable vent. The actuator is divided into two cells by a power transfer shaft to which is attached a vent follower. In an equilibrium position, the vent is closed off by the vent follower. Moving the vent location to either side of the vent follower causes fluid or gas to escape from one or the other cell. This creates a pressure difference between the cells causing the vent follower to move until it arrives at an equilibrium position. When the vent follower is caused to move the power transfer shaft also moves accordingly. In the rotary version, the vent follower operates in a wiper-type fashion. Movement of the vent follower causes the power transfer shaft to rotate. In the linear version, the power transfer shaft is attached to a piston head. The piston head is fitted into a cylinder which divides the cylinder into two hydraulic or pneumatic cells.

Abstract: A hydraulic idling-regulating valve comprising at least two mechanically operated through-flow valves which can be controlled to move alternatively into a flow position and a closure position and which are both closed in a neutral central position. An electromechanical specified-value setting system positions the piston of a hydraulic drive cylinder, which system comprises a hollow shaft that can be rotated by a number of revolutions correlated with the specified value, and an actual-value feedback system is provided which comprises a feedback spindle which is in engagement with an internal thread of the hollow shaft and which performs a number of revolutions correlated with the piston movement. The valve-actuating element is subjected to the same displacements as the specified-value setting shaft.

Abstract: A hydraulic servo actuator has an outer case, a rotatable shaft extending through the case, an input sleeve rotatably mounted on the shaft and having hydraulic fluid supply and discharge passages therein and having surface grooves communicating with the passages, an output member on the shaft and movably abutting the input sleeve and having fluid supply and discharge passages therein and having surface grooves communicating with the passages and being opposed to corresponding grooves on the input sleeve, the outer casing and the output member defining an actuating chamber therebetween into which the passages in the output member open; the actuating chamber is shaped for causing the output member and the outer case to rotate relatively and rotate the shaft and case relatively when fluid supplied into the chamber from the passages under control of relatively rotation of the input and output members creates an unbalanced pressure on parts of the actuating chamber.

Abstract: The actuating mechanism comprises a force step-up transmission with an output member (25) and an input member (17) connected to a control system via a hydraulic distributor (16), these input and output members being coaxial, the step-up transmission consisting of a coaxial train of epicyclic gears (32, 37, 38), and the double-acting power-assistance motor comprises a likewise coaxial rotor (9) with blades (10) which is connected to the output member (25) and which rotates in a cavity (7) formed by the box (4) of the mechanism.

Abstract: An assistor for operating a transmission, to be installed between the gearshift lever and the shift lever for actuating the shift jaws of the transmission, comprises a semicylindrical cylinder, a vane type piston adapted to turn slidingly within the cylinder, and a directional control valve for supplying a fluid to chambers defined by the vane of the piston. Operation of the gearshift lever opens the directional control valve to supply the fluid to one of the chambers separated by the piston vane, whereby the piston is turned and its turning output is transmitted from its boss to the shift lever.

Abstract: The actuating mechanism comprises a step-up transmission having an input member (8, 9) connected to an actuation control system (13) by means of a hydraulic distributor (12) controlling at least one double-acting hydraulic power-assistance motor, and an output member in the form of a disc-shaped body (6) rotating about an axle (5) in a box (1, 3), the body having a toothed sector (7) intermeshing directly with a pinion (8) of the input member (9) and forming, in the box, the piston means of the power-assistance motor.

Abstract: A hydraulic servo-actuator has a casing embracing therein a hydraulic fluid chamber which is divided into two hydraulic drive chambers by a vane projecting from a first shaft. To each of the divided chambers are connected an oil feeding passage provided with a variable restrictor and intended for the feeding of pressurized oil and an oil discharge passage intended for the discharging of the pressurized oil. A second shaft is coaxially disposed relative to the first shaft, and the first and second shafts are correlated with each other in such a way that the relative rotary displacement occurring between the two shafts controls the aperture of the oil discharge passages communicating with the divided chambers. The difference between the static pressures which are consequently produced within the divided chambers because of the aperture of the oil discharge passages causes the vane to swing, making it possible to control the torque even when the vane is in the neighborhood of its neutral position.

Abstract: An electrohydraulic proportional actuator for converting an electrical input signal to proportional mechanical output. Fluid power may be derived from pressurized fuel or lubricating oil of an associated engine. The actuator may be used to drive any engine function requiring modulated control. The mechanical output is proportional to the electrical input. The actuator includes mechanical feedback to linearize the response function, thus eliminating the need for closed loop operation of the system in which the actuator is used. Both linear and rotary actuators are disclosed in various embodiments. Each type is capable of operation with either a proportional solenoid and valve or a force rebalance solenoid and valve.

Abstract: A variable displacement axial piston pump has a rocker cam for controlling the output of the pump. The rocker cam is driven by a fluid motor member. A valve with a follow-up device regulates pressure fluid flow to the fluid motor member to move the rocker cam. Both the fluid motor member and a part of the follow-up device are rigidly secured to and movable with the rocker cam to provide precise positioning of the rocker cam.

Abstract: A variable displacement axial piston pump has a rocker cam for controlling the output of the pump. The rocker cam is driven by a fluid motor member. A valve with a follow-up device regulates pressure fluid flow to the fluid motor member to move the rocker cam. Both the fluid motor member and a part of the follow-up device are rigidly secured to and movable with the rocker cam to provide precise positioning of the rocker cam.

Abstract: A hydraulic guide wheel blade adjusting mechanism for the turbine and/or the compressor of an exhaust-gas turbo-supercharger of an internal combustion engine, which includes a control slide valve and servo-pistons; the adjusting mechanism is thereby accommodated within the housing of the turbo-supercharger between the turbine and the compressor.

Abstract: A rotary type hydraulic servo-mechanism constructed with a hollow-cylindrical casing, an input shaft extending through the casing, a driven output member slidably mounted on the casing, a servo-valve mechanism formed in the surface of the input shaft which slides on the driven output member, a hydraulic fluid chamber to generate a resisting torque against rotational force of the input shaft, and a passage to connect this hydraulic fluid chamber with the servo-valve mechanism, and hydraulic drive chambers defined by a space between the inner wall of the hollow cylindrical casing and the outer periphery of the driven output member.