Abstract: Disclosed is an electro-hydraulic actuator for providing mechanical actuation. The electro-hydraulic actuator comprises a housing having a first chamber and a second chamber and a gear pump arranged within the first chamber. The gear pump is configured to pump fluid from the first chamber into the second chamber. Furthermore, the electro-hydraulic actuator comprises a piston assembly comprising a piston-head slidably arranged within the second chamber, a piston-rod coupled to the piston-head, and a rack configured as piston-rod. The rack comprises a plurality of teeth and the rack is configured to move linearly corresponding to the linear movement of the piston-rod. Moreover, the electro-hydraulic actuator comprises a shaft arranged within the first chamber and orthogonally to the piston-rod and a pinion mounted on the shaft. The pinion is configured to rotate upon linear movement of the rack to cause rotation of the shaft, for providing the mechanical actuation.

Abstract: A steam reciprocating piston engine that uses a pressurized working fluid to drive first and second pistons in reciprocating power strokes is disclosed. A piston is configured for reciprocating motion within the cylinder and traverses between bottom dead center and top dead center positions. An uppermost stop is reached wherein the working fluid is allowed to escape the cylinder through one or more exhaust ports whereby the fluid travels through a closed loop circuit ultimately directing pressurized fluid back into the cylinder inlet. Momentum causes a spring connected mass to continue upward maintaining the piston above the exhaust port so as to allow escape of the working fluid. Return of the piston and mass is caused by opposite movement of a second piston whereby another stroke is initiated. Power output may be transferred to any suitable system.

Abstract: A steam reciprocating piston engine that uses a pressurized working fluid to drive first and second pistons in reciprocating power strokes is disclosed. A piston is configured for reciprocating motion within the cylinder and traverses between bottom dead center and top dead center positions. An uppermost stop is reached wherein the working fluid is allowed to escape the cylinder through one or more exhaust ports whereby the fluid travels through a closed loop circuit ultimately directing pressurized fluid back into the cylinder inlet. Momentum causes a spring connected mass to continue upward maintaining the piston above the exhaust port so as to allow escape of the working fluid. Return of the piston and mass is caused by opposite movement of a second piston whereby another stroke is initiated. Power output may be transferred to any suitable system.

Abstract: A link has first and second ends coupled, so as to be axially shiftable, respectively to two shafts that include a reference point located in a base and cross each other. A gas actuator has an inner space that has gas pressure pressing the first end of the link toward the reference point so as to shift the first end of the link such that a distance between a first end position of the link and the reference point is equal to or more than a distance between the first and second ends in a state where the inner space has a volume equal to zero obtained by extrapolating variation of the inner space volume relative to the first end position. The second end and a lift section that is vertically shiftable with respect to the base are coupled by means of a coupling section.

Abstract: Actuator controller comprising a body (12) with an inlet port (14) coupled to a source of pressurized fluid and in flow communication with primary and secondary spool bores (16, 20); primary and secondary spools (60, 62); first and second cross flow ports (48, 52) communicating said primary and secondary spool bores, compression and expansion outlet ports (53, 54) for applying pressurized fluid to a return-biased actuator (110); and a venting outlet port (23); wherein return action of the working piston of the actuator is facilitated with aid of pressurized fluid already gained in the system.

Abstract: A load transfer device for use with tandem mounted actuators. The load transfer device includes an actuator coupling assembly and a ground connection assembly. The actuator coupling assembly connects the first actuator to the second actuator and includes a movement apparatus. The movement apparatus is configured to allow the housing of the first actuator to move relative to the housing of the second actuator. The ground connection assembly is associated with the actuator coupling assembly and movably connects the first and second actuators to a rigid support structure. During a load transfer operation, the actuator coupling assembly transfers an unequal load from the first actuator to the second actuator. In particular, the movement apparatus allows the first actuator to move relative to the second actuator. Further, the actuator coupling assembly is configured to transpose movement of the first actuator into a forced, reciprocal movement of the second actuator.

Abstract: Pressure fluid operated servo system method and apparatus including a servo valve operable by an input signal to effect a system output movement; and which servo valve is responsive to the time rate of input signal receipt to vary a gain ratio of system output magnitude compared to input signal value; and method of making such a servo valve.

Abstract: A pushbutton control system for raising and lowering the dump body of a dump vehicle. Included are "up", "hold" and "down/float" switches which are connected in circuit with "up", "down" and "float" solenoid valves. These valves on energization direct pressurized air into the "up", "down" and "float" chambers of two air cylinders included in an actuating mechanism for a hoist valve controlling the telescopic hoist cylinders of the vehicle. The dump body is raised upon depression of the "up" switch with the consequent opening of the "up" valve. The depression of the "down/float" switch, resulting in the opening of the "down" valve, causes the dump body to lower by the forced contraction of the hoist cylinders. Upon subsequent release of the "down/float" switch the "float" valve opens to allow the dump body to lower under its own weight. The depression of the "hold" switch, with the consequent closure of all the solenoid valves, makes it possible to hold the dump body against movement in any desired position.

Abstract: The invention relates to an oil well jack having a walking beam mounted on a frame for motion in a vertical plane; and a plurality of hydraulic actuators connected to move the walking beam. The amplitude of movement of the beam as well as the frequency of the stroke are adjustable through regulation and control of the hydraulic system.

Abstract: A redundant swashplate control system includes five or more actuators coupled to the swashplate. A feedback network independently controls each actuator to track a commanded position and a reference ram differential pressure that it related to the ram differential pressures sensed from all of the actuators.

Abstract: A piston-rack rotary actuator having four pistons each with an integral rack and each displaceable along a cylinder unique thereto, the racks meshing with a center gear at equiangularly spaced points and causing angular movements of a shaft about its rotational axis when said pistons are displaced along their respective cylinders, said gear being secured to said shaft. The racks are formed in respective webs which are supported by the actuator body in such a manner as to prevent piston-slewing which would otherwise occur due to the separating force generated by the meshing gear and racks when said racks are moved relatively to the gear.

Abstract: A flight control system is provided for a helicopter furnishing safety feres, and providing back up control in the event of failure of controls of the rotary head swashplate of a helicopter. The swashplate is regulated by a series of actuators which are angularly positioned at particular settings around the swashplate. In the event of a control system failure, a supplemental system controls the selected settings for the swashplate, rotary head, and spar root and blade assemblies of the helicopter.

Abstract: A high efficiency, low cost fluid pressure engine. This engine converts reciprocating piston motion to rotary output in a novel manner. The engine comprises at least two parallel pistons adapted to reciprocate in cylinders within an engine block closed by upper and lower heads. Each piston is rigidly secured to a piston rod located along the cylinder centerline and extending through substantially fluid tight packing in the lower head. The lower end of each piston rod is flexibly connected to a first connecting means which also includes an opening surrounding a first crank pin. A pair of reciprocating valve means, located within said engine block, are adapted to selectively introduce and exhaust the engine drive fluid into and out of the cylinder above and below the pistons. Valve push rods secured to said valve means are connected to a second connecting means which also has an opening surrounding a second crank pin.

Abstract: A high efficiency, low cost fluid pressure engine. This engine converts reciprocating piston motion to rotary output in a novel manner. The engine comprises at least two parallel pistons adapted to reciprocate in cylinders within an engine block closed by upper and lower heads. Each piston is rigidly secured to a piston rod located along the cylinder centerline and extending through substantially fluid tight packing in the lower head. The lower end of each piston rod is flexibly connected to a first connecting means which also includes an opening surrounding a first crank pin. A pair of reciprocating valve means, located within said engine block, are adapted to selectively introduce and exhaust the engine drive fluid into and out of the cylinder above and below the pistons. Valve push rods secured to said valve means are connected to a second connecting means which also has an opening surrounding a second crank pin.

Abstract: A high efficiency, low cost fluid pressure engine. This engine converts reciprocating piston motion to rotary output in a novel manner. The engine comprises at least two parallel pistons adapted to reciprocate in cylinders within an engine block closed by upper and lower heads. Each piston is rigidly secured to a piston rod located along the cylinder centerline and extending through substantially fluid tight packing in the lower head. The lower end of each piston rod is flexibly connected to a first connecting means which also includes an opening surrounding a first crank pin. A pair of reciprocating valve means, located within said engine block, are adapted to selectively introduce and exhaust the engine drive fluid into and out of the cylinder above and below the pistons. Valve push rods secured to said valve means are connected to a second connecting means which also has an opening surrounding a second crank pin.

Abstract: A high efficiency, low cost fluid pressure engine. This engine converts reciprocating piston motion to rotary output in a novel manner. The engine comprises at least two parallel pistons adapted to reciprocate in cylinders within an engine block closed by upper and lower heads. Each piston is rigidly secured to a piston rod located along the cylinder centerline and extending through substantially fluid tight packing in the lower head. The lower end of each piston rod is flexibly connected to a first connecting means which also includes an opening surrounding a first crank pin. A pair of reciprocating valve means, located within said engine block, are adapted to selectively introduce and exhaust the engine drive fluid into and out of the cylinder above and below the pistons. Valve push rods secured to said valve means are connected to a second connecting means which also has an opening surrounding a second crank pin.

Abstract: A high efficiency, low cost fluid pressure engine. This engine converts reciprocating piston motion to rotary output in a novel manner. The engine comprises at least two parallel pistons adapted to reciprocate in cylinders within an engine block closed by upper and lower heads. Each piston is rigidly secured to a piston rod located along the cylinder centerline and extending through substantially fluid tight packing in the lower head. The lower end of each piston rod is flexibly connected to a connector which also includes an opening surrounding a first crank pin. Swinging links are provided interconnecting each of the connector and the engine housing to constrain the movement of the piston rods and valve push rods to substantially linear motion. The crank pin is mounted on a crank plate offset from an output drive shaft so that as steam or another fluid drives the pistons, linear motion is converted to rotary output motion.

Abstract: A vibration-free hydraulic power system having an opposing pair of pistons adapted to be moved in unison with the same stroke and equal force, but in opposite directions, one of the pistons being operatively connected to an external mass to be moved, the other of the pistons being operatively connected to a reactive mass the weight of which is identical to the weight of the mass being moved, the reactive mass acting to maintain the system in an equilibrium state during its complete operating cycle, the system incorporating a pair of control valves each having a series of sequentially acting valve elements which control fluid flow to and from the system, the pistons and control valves working at all times against solid columns of fluid under positive but variable pressure.

Abstract: A high efficiency, low cost fluid pressure engine. This engine converts reciprocating piston motion to rotary output in a novel manner. The engine comprises at least two parallel pistons adapted to reciprocate in cylinders within an engine block closed by upper and lower heads. Each piston is rigidly secured to a piston rod located along the cylinder centerline and extending through substantially fluid tight packing in the lower head. The lower end of each piston rod is flexibly connected to a first connecting means which also includes an opening surrounding a first crank pin. A pair of reciprocating valve means, located within said engine block, are adapted to selectively introduce and exhaust the engine drive fluid into and out of the cylinder above and below the pistons. Valve push rods secured to said valve means are connected to a second connecting means which also has an opening surrounding a second crank pin.

Abstract: An overload relief valve for use in preventing damage to the hydraulic system for adjustably positioning a working element, such as a blade. A single relief valve permits relief of high fluid pressure developed in either of the control cylinders by providing a crossover function therebetween under such conditions, as well as to relieve the fluid to tank in the event of a high pressure condition existing in both cylinders concurrently. The crossover relief may be effected by a similar first preselected high pressure condition in either of the cylinders.

Abstract: A motion change transmission includes a rotor rotationally supported by and/or within a framing assemblage or housing. The face of the rotor is provided with alternating, axially and circumferentially extending hills and valleys. At least one rod is disposed transversely relative to the rotor and is pivotal in a given plane relative to the assemblage or housing and is operatively engageable with the face of the rotor such that when one end of the rod traverses a rotor hill, the other end of the rod simultaneously traverses a rotor valley. Either or both ends of the rod are connected to reciprocating members. When means are provided for driving the reciprocating members, the transmission provides for the conversion of reciprocating motion to rotary motion. And when means are provided for driving the rotor, the transmission provides for the conversion of rotary motion to reciprocating motion.

Abstract: The invention relates to a hydraulic control system for a vehicle steering system or the like. The system includes two hydraulic cylinders each having a piston and a piston rod extending through one end thereof with the rod side of each piston having a smaller pressure area than the opposite side thereof. The pistons are mechanically interconnected by their piston rods. Each of the cylinders has first and second ports respectively at the nonpiston and piston ends thereof. There is a source of fluid pressure and an exhaust tank and a separate valve unit for each of the cylinders. A valve operating unit includes a steering wheel for operating the valve units in unison. The valve units have passages arranged so that for turning in either direction the first and second ports of one cylinder and the second port of the other cylinder are connected to the pressure source. At the same time the first port of the other cylinder is connected to said exhaust tank.

Abstract: This invention is directed to fluid actuated apparatus for automatically restricting the flow of fluid in conduits leading to and/or from fluid actuated cylinder means for causing pivotal movement of a member, such as the turret carrying the boom and bucket of a backhoe, so that the speed of pivotal movement of the member is rapid during one portion of its pivotal movement but is automatically reduced during a predetermined portion of its subsequent pivotal movement, thereby minimizing failures of the components of the member and the fluid system and improving the braking action for reducing the speed of pivotal movement of the member. In one embodiment, both the flow of fluid to the operative fluid actuated cylinder and the flow of fluid from the inoperative fluid actuated cylinder are restricted substantially simultaneously by fluid restricting means so that the linear velocities of the rods of both cylinders are reduced substantially simultaneously by the fluid restricting means.

Abstract: A device for controlling hydraulic motors as in an aircraft "fly-by-wire" system wherein redundant hydraulic motors and controls are required to protect against failure of portions of the system or device. The device includes two master valves for controlling flow of fluid to and from the motors, one controlled by electrical signals from a command station and the other controlled mechanically through manual or automatic operation. There is a transfer valve for selecting which of the master valves is to be operable and to provide for smooth transition of control from the electrically controlled valve to the mechanically controlled valve.

Abstract: A two-axis positioning servoactuator includes a support, a movable member arranged adjacent the support for independent pivotal movement relative thereto about each of two perpendicular intersecting axes, a pair of differential piston and cylinder actuators operatively interposed between the support and movable member for effecting such angular movement about each of the axes, an electrohydraulic servovalve for each of the actuators and operatively associated therewith to control the same, and means providing a position feedback signal to the corresponding servovalve for effecting controlled movement of the member about each of the axes.

Abstract: A pneumatically driven device which in the exemplary form of the invention is an air tool driven by pistons. In the exemplary form there are two pistons having racks which drive the reciprocatable shoe through pinion gears. One piston drives in each direction. Each piston at the end opposite the driven end has an annular groove in it with a sealing ring with ports for communicating air to the area behind the ring for pushing it out against the inside surface of the cylinder. During a piston stroke at this end of the piston air is compressed to provide a cushioning and braking effect which improves the overall operation, and avoids excessive wear.

Abstract: The actuator includes two piston motors interconnected in opposed driving relation with a fixed axis rotary shaft, and fluid pressure control means for controlling the piston motors so that they rotate the shaft bi-directionally at constant rotational velocity with constant resultant torque. The two piston motors preferably are of different effective cross sectional areas, the smaller motor being continuously pressurized with fluid composed solely of fluid from a fluid pressure source, and the larger motor being selectively pressurized with fluid made up of fluid from the fluid pressure source together with fluid exhausted from the smaller motor. A single valve controls fluid flow to and from the piston motors to effect bi-directional shaft rotation, or maintain the shaft in a fixed position. The valve may be operated automatically by servo control means responsive to the positions of the piston motors.

Abstract: A rock drill has a housing accommodating pistons defining working chambers. Rotary drive of a drill steel has an overrunning clutch and a screw pair. The screw pair is arranged between the pistons and is formed by outer and inner helical threads respectively provided on these pistons. One of the pistons is kinematically connected with the housing, and the other piston which cooperates, during the drilling, with a chuck receiving the drill steel shank is in force transmitting connection with the rotary drive of the drill steel.The invention is aimed at lowering vibration of the rock drill housing by arranging the screw pair of the rotary drive between the pistons.

Abstract: A hydraulic system for use in engines having reciprocating pistons and rotary piston rods wherein hydraulic fluid is supplied to each cylinder to not only lubricate the piston and cylinder but also to facilitate the movement of the piston to the top dead center position.

Abstract: A hydraulic swivel drive with two adjusting cylinder-piston systems the connecting rods of which are pivotally connected to a pivotally mounted member to be actuated by the hydraulic swivel drive. The cylinder-piston units are mounted on a base member, e.g. a base plate, which base member is provided with a servo-valve controlling the supply of actuating fluid to the cylinder-piston units which are arranged in V-formation and are hooked up with the pivotally mounted member so as to be symmetrically arranged with regard to the pivot axis of the pivotally mounted member. The cylinder-piston units are directly connected to the base member and their connecting rods are pivotable relative to the axis of their pertaining cylinder.

Abstract: A pneumatic actuator having a double-acting piston separating two pressure chambers, spring means to urge the piston in one direction; and valve means adapted to admit compressed air to one of the chambers and thus to load the spring means, then to transfer some of said air into the other of the chambers at a selected phase-position of said piston, and then to open the one chamber to atmosphere so that the combined forces of the spring means and of the compressed air acting on the piston in said other chamber complete the power stroke of the actuator.

Abstract: An adaptive actuator system comprising a rotatable shaft operatively coupled to a torque biasing means for biasing the rotational direction of the shaft, and also operatively coupled to a counter torque developing means for sensing the rotational bias of the shaft and providing a counter torque proportional to the rotational bias.