Abstract: A device capable of comparing the travel position of an output shaft of a diaphragm actuator or cylinder with the current level of an electronic input signal and further being capable of manipulating the pressure of a separate air signal piped to a diaphragm actuator or cylinder in order to correct any imbalance between such a shaft position and a given electronic signal level, including the ability of varying its dynamic response through built in adjustments.

Abstract: A valve used to control the flow of a magnetorheological fluid, in which the mechanical properties of the magnetorheological fluid are varied by applying a magnetic field, is described. The valve can comprise a magnetoconducting body with a magnetic core that houses an induction coil winding, and an hydraulic channel located between the outside of the core and the inside of the body connected to a fluid inlet port and an outlet port, in which magnetorheological fluid flows from the inlet port through the hydraulic line to the outlet port. Devices employing magnetorheological valves are also described.

Abstract: A controller (11) and a system for controlling the flow of fluid to a fluid pressure operated device (C) are disclosed. The controller is of the type including a rotatable spool valve (35) and a relatively rotatable sleeve valve (37). Relative rotation between the spool and sleeve define a main fluid path (MFP) and relative axial movement therebetween defines an auxiliary fluid path (AFP). An actuator (65) generates a mechanical output (71) in response to an electrical input signal (CS) to move the sleeve (37) between its neutral axial position (FIG. 6) and an axial operating position (FIG. 7). Axial movement of the sleeve is controlled by a joystick (J). The system includes various sensors (S,PS,G,P), which can sense a predetermined condition and generate an interrupt signal to interrupt or change the gain of the electrical input signal (CS).

Abstract: A position-controlled actuator including a double acting pneumatic actuator, a selector valve which causes function of the actuator, a comparator which controls the action of the selector valve in response to a comparison between an input signal and a signal indicative of the position of the actuator, and a feedback link which provides the comparator with a signal indicative of the position of the actuator. The actuator would have oscillation damping seals such as seals of VITON brand fluorocarbon rubber.

Abstract: An improved fluid controller (15) is provided having both rotary valving (47) actuated by the steering wheel (17), and axial valving (49) controlled by an electro-hydraulic valve (113) in response to a correction signal (31). In one embodiment, both the rotary valving and the axial valving are achieved by a primary valve member (63) and a follow-up valve member (65), and both the rotary and axial valving can be actuated simultaneously. Also disclosed is a logic control system for closed-loop control of the electro-hydraulic valve, whereby performance problems such as self-steering wander, drift, and others are substantially eliminated.

Abstract: A linear actuator comprising a linear motor, more especially in the form of a pneumatic motor, which has a housing containing an axially moving piston which is connected with an actuating rod extending out of the motor housing at a working end thereof, a control device, for instance in the form of valve means, for operation of the motor, and a sensor means responsive to certain positions of the actuating rods. In order to simplify and cheapen production of such an actuator while facilitating and speeding up installation of the linear motor, the control device and sensor device are permanently connected to form a readily handled working unit, and the control device and the sensor device are arranged on the control end, opposite to the working end, of the linear motor.

Abstract: A hydraulic steering apparatus for a construction vehicle, which has been developed for the purpose of improving the steering control performance of an apparatus of this kind by preventing the occurrence of nonsynchronousness between a steering wheel and a knuckle arm or some other pivotable member, and eliminating a dead zone ascribed to an operation of a link mechanism. This steering apparatus has a pilot valve (2) connected directly to a steering wheel, a main control valve (7) provided separately from the pilot valve and adapted to be operated by a pressure oil sent from a pilot pump (9) which is controlled by the pilot valve, a steering cylinder (6) to which a pressure oil is supplied from a main pump (8) via the main control valve, and a feedback line (4) connected between a pivotable member (5), such as a knuckle arm connected pivotably to a piston rod in the steering cylinder and a spool in the pilot valve.

Abstract: The invention relates to the control of a hydraulic jack which can be used, for example, for controlling the orientation of the rear wheels of a vehicle with front guiding wheels. In the event of a failure in the supply of fluid under pressure to the chambers (3, 4) of the jack, these chambers are isolated and the piston (2) is maintained in the position which it occupied when the failure occurred, by means of non-return valves (12). However, when certain conditions are satisfied, for example a sufficiently low speed, the electronic control member (20) activates an auxiliary circuit (30 to 39) in order to return the piston to its middle position and allow driving of the conventional kind with the rear wheels in line.

Abstract: For converting a stepwise translation movement into a continuous translation movement and arrangement and a method is provided which have at least two fluid-operated cylinder-piston units with cylinders are rigidly mechanically connected with one another and pistons movable in the cylinders between end positions and having piston rods, removably arranging clamping mechanisms on the pistons of the cylinder-piston units, arranging end position sensors in the regions of the end positions of the piston of a respective one of the cylinder-piston units, arranging end position pre-signal sensors so that they are axially spaced relative to the end position sensors, connecting the sensors with electronic a control unit, and producing by the electronic control unit signals for supplying a working fluid to the cylinders of the cylinder-piston units in an alternating manner.

Abstract: An optical actuator position demand signal through optic fiber 14 is focused on one side 32 of optical fluidic interface 16. A second optical signal through optic fiber 56 is attentuated 50 in proportion to actuator 38 position and focused on a second side 34 of the interface 16. Amplified fluidic signals 68, 70 drive the actuator until the demand signal 14 and actual signal 58 are in balance.

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: An apparatus for controlling the flow of a pressure fluid in a motor includes an arm which cooperates with a locking device to regulate the flow of the pressure fluid through a shut-off member or valve. The arm is connected to a lever which is pivotable about the same axis as the arm. Through resilient means, the arm and the lever are prestressed so that upon movement of the lever into a predetermined position, the arm which is locked in its end positions by a respective lock pawl is released and impelled from one end position into the other. During the movement of the arm, the shut-off valve is actuated so as to regulate the pressure fluid.

Abstract: A single-lever hydraulic control system for marine applications which controls both engine throttle and the transmission engaged therewith, and which allows for multiple control stations.

Abstract: A portable hydraulic tool, such as a hydraulic secateurs, is of the kind having a single acting ram including a driving piston with its piston rod connected to at least one movable operating member such as a cutting element of the tool, the piston being movable in fluid tight manner in a bore under the thrust of hydraulic fluid acting on a working face of the piston, the improvement being that there is provided a return chamber the volume of which decreases when the driving piston is displaced in its working stroke, the return chamber containing a compressible fluid under pressure such that, when the thrust exerted on the piston by the hydraulic fluid becomes less than the thrust exerted on the piston by the compressible fluid, the piston is caused to carry out a return stroke by the expansion of the compressible fluid.

Abstract: A closed center four-way poppet actuator control device is incorporated into a pneumatic actuation system for controlling the movement of flight surfaces. The closed center four-way poppet actuator control device has a housing, a pair of two-way poppet valves in the housing, a rocker arm assembly mounted on the housing and connected to the pair of two-way poppet valves, and a diaphragm assembly also mounted in the housing and in contact with the two-way valves. A torque motor-driver assembly connected to the diaphragm assembly actuates the two-way valves as determined by control signals. The rocker arm causes the two-way valves to function oppositely each other: one allows high pressure gas to be input to a lobe motor actuator while the other allows gas to be output from the lobe motor actuator. Each two-way valve has a cylindrical poppet valve for inletting the gas to the actuator and a disk poppet valve for outputting the gas from the actuator to a vent.

Abstract: A power steering system for motor vehicles, wherein a steering nut, connected to a steering worm in such a manner that the steering worm is driven thereby, is rotatably and axially non-displacably mounted in a working piston and is also provided with a control arm passing through both a radial recess in a working piston and a radial opening in a cylinder housing that receives the working piston. An end of the control arm which is radially outermost with respect to an axis of the piston actuates a spool valve for adjusting the working pressure. Two corresponding followers are provided for defining the end stroke positions of the working piston. The followers are mutually engagable to lower or shut off a working pressure in the system. One of the followers is disposed opposite the working piston relative to the piston axis and the other is located opposite the cylinder housing relative to the cylinder axis with a zero motion.

Abstract: An adjusting mechanism (92) is provided between a valve spool (62) and a valve actuating lever (26) whereby with the lever (26) locked in a selected position, the mechanism (92) is manipulated to move an element (99) carried by the valve spool (62) into alignment with an indicator (110) that has been predetermined to be the selected setting of the valve. With the element (99) aligned with the indicator (110), the mechanism (92) is locked so that the valve spool (62) is in the selected setting when the lever (26) is in the selected position. A lock-down apparatus (70) is provided for use in locking the lever (26) in the selected position while the adjusting mechanism (92) is being manipulated.

Abstract: A load relief device for a power steering system of a vehicle. The load relief device provides release of loads from a hydraulic pressure supply pump of the power steering system when the output member of the system is near the end of its stroke by short-circuiting between a hydraulic pressure source and an oil reservoir of the power steering system. The load relief device includes an assembly for detecting the end of a stroke being executed by the power steering system, and upon detection of the end of the stroke, the assembly operates to bring a four-way valve of an open center type to a neutral position thereof, regardless of the steering torque being applied to the power steering system.

Abstract: An actuator system is disclosed which modulates a linear output shaft associated with a working control valve or the like in response to a control signal input. The system includes a feedback control link, a pneumatic positioner, a pneumatically controlled hydraulic valving system and a hydraulic cylinder and piston assembly controlled by the hydraulic valving system. The hydraulic valving system includes a three-position, four-way valve actuated by pneumatic binary output signals from a signal conditioner which is in turn controlled by the positioner. Hydraulic flow to the three-position, four-way valve may also be controlled from the signal conditioner in response to positioner output for most effective actuation of the hydraulic cylinder and piston assembly. Failure modes are also disclosed with the present system. The resulting system exhibits extremely rapid response times and high accuracy with dynamic stability.

Abstract: A torque control for a fluid operated motor includes a first gear to be driven through operation of the motor and a second gear in driving engagement with said motor and maintained in a generally stationary position during normal operation thereof. The torque control further includes a drive mechanism connected to the first gear and to a load to be rotationally driven through operation of the motor. A valve is provided in the fluid supply to the motor to open and close the supply of fluid thereto. Disconnect means is operatively connected to the second gear and the valve to maintain said valve in an open position to permit supply of fluid to said motor when the second gear is stationary. The second gear rotates when the torque required from the motor to rotate the load exceeds a predetermined magnitude to move the disconnect means relative to the valve to close the valve to terminate the supply of fluid to the motor.

Abstract: A control valve unit (10) disclosed includes a slide mechanism (14) mounted on a base (40) of the unit, a control member (18) driven by a hydraulic linear actuator (12) controlled by the unit, and a control valve (22) that feeds hydraulic fluid to the actuator and has a deactivator (24) that is engaged and moved by a pair of slides (16a,b) of the slide mechanism under the impetus of the control member movement in order to terminate driving of the actuator at its limits of movement. The slide mechanism includes a slideway on the base and a pair of fixed stops (62a,b) between which the movable slides are supported on the slideway and biased by a helical spring (68) against the stops. The helical spring is aligned with openings (66) in the slides and the control member (18) extends through the spring and the slide openings. Lugs (76a,b) on the control member for moving the slides are preferably adjustable so as to permit adjustment of the limits of actuator movement.

Abstract: A valving system for regulating the pressure of the fluid within a hydraulic actuator of the type having a hydraulic cylinder and movable piston therein that separates the cylinder into a first and second chamber comprises sensing apparatus in fluid communication with the first chamber of the hydraulic actuator cylinder. The sensing apparatus senses the differences in pressure between the fluid within the first chamber and the fluid in the second chamber. The valving system further includes a pressure regulator for regulating the pressure within the first chamber in response to the sensed pressure difference. Apparatus is also included for communicating the magnitude of the sensed pressure difference to the pressure regulator.

Abstract: A control valve unit (10) disclosed supplies hydraulic fluid to an actuator (12) in a manner that controls both acceleration and deceleration of the actuator movement. A supply valve (14, 22) of the unit is movable from a central closed position in opposite directions to open positions and back to the closed position by a servomechanism (16) and a control circuit (18) that operates the servomechanism to cooperatively control the supply of the hydraulic fluid to the actuator in a manner which controls both acceleration and deceleration of the actuator movement. A control member (62) of the servomechanism operates the supply valve and is moved in a controlled manner by cooperative operation of a pair of hydraulically operated pilot pistons (88a, b), a pair of acceleration control pistons (90a, b), and a pair of deceleration cams (84a, b). Directional and flow control valves (89, 92) of the control circuit operate the pilot pistons and the acceleration control pistons in cooperation with each other.

Abstract: A hydraulic control arrangement with a feedback device for positioning an implement comprises a positioner including a fluid operated cylinder and piston unit, the piston of which is connected by a plurality of linkage elements to the implement. A first pump delivers through a pressure line fluid under pressure into the cylinder. A two-port three-position valve is interposed in the pressure line movable from a neutral position in which the fluid fed by the first pump is directed to a reservoir, to two operating positions to opposite sides of the neutral position, and in which one of the operating positions fluid fed by the first pump passes into the cylinder and in the other of the operating positions fluid from the cylinder can flow to the reservoir. A pair of pilot chambers are arranged at opposite ends of the valve for moving the latter from the neutral to either of the working positions. A second pump provides fluid under pressure for operating the valve.

Abstract: The invention relates to a positioner device for positioning the piston and piston rod of a double-acting, pneumatic operating cylinder at a preselected position for setting the position of a device connected thereto, such as the lever of a throttle valve, for example, with the positioner device having a locking device connected to the piston rod which can be controlled by a control valve for securing and maintaining the piston and rod in the selected position, without variance, until deliberately changed.

Abstract: A steering control with a hydraulic follow-up wherein a movable valve member of a control valve is automatically brought back to a nonsteering disposition as a result of the movement of the device being steered to the desired steering position. Movement of the device is effected by a pair of steering cylinders. Control of the movable valve member is effected by a variable volume storage device which receives hydraulic fluid from the control valve and returns the fluid to the control valve as a function of the relationship of the steering mechanism and device to be steered.

Abstract: A hydraulically actuated control valve normally includes a hydraulic cylinder which has an internal piston connected through a shaft to the actuating mechanism in the control valve. Ports are provided on each side of the piston through which fluid flows to move the piston axially inside the cylinder. The piston can be controlled electrically by an electro-hydraulic servo-controlled valve which includes an electrical input, a mechanical feedback input, and first and second outputs. The outputs are connected to the two ports in the cylinder, a mechanical feedback is coupled to the shaft and the mechanical feedback input of the control valve, and an electrical circuit is coupled to the electrical input of the servo-controlled valve to signal the hydraulic portion of the valve to either move the shaft in a manner to close the valve or move the shaft in a manner to open the valve.

Abstract: A hydraulic drive mechanism for a chucking device on a workpiece spindle on a gear hobbing machine. A chucking piston is movable back-and-forth in the chucking cylinder and rotates with the workpiece spindle. Pressure medium is fed through a nonrotating supply member, for example, a connecting sleeve. The chucking cylinder is secured to the face plate so that the cylinder end plate which seals off the connecting piece forms a planar surface with the surface of the face plate. Pressure medium is supplied to the chucking cylinder through flexible hoses.

Abstract: A cable is connected between the dump body of a dump truck and the movable control member of an hydraulic valve to automatically shift the valve from its "raise" position to its "neutral" position when the dump body approaches its uppermost raised position. There is means to prevent inadvertent transmission of forces from the cable to the movable control member to thereby prevent accidental lowering of the dump body due to an inadvertent pull on the cable.

Abstract: A hydraulic control circuit for the steering system of an articulated vehicle is provided having a first pump means for delivering fluid under pressure and directional control valve means in fluid communication with the first pump means for controlling the direction of flow of the pressurized fluid. A second pump means, responsive to a steering input signal, develops an output indicative of a desired change in vehicle direction. An actuator means is connected to the directional control valve means for controlling the position of the directional control valve means, and said actuator means is in fluid communication with the second pump means so as to receive the output therefrom. A feedback means is placed in fluid communication with the actuator means for developing a feedback signal to counteract the effect of the second pump output, and a means is placed in fluid communication with the feedback means for varying the feedback signal to thereby vary the rate of counteracting the second pump output.

Abstract: Control arrangement including an actuator, such as an air motor, for operating the jet deflector flaps of a thrust reverser, and a pilot valve and a control valve for operating the actuator. The pilot valve controls flow of high pressure air from the jet engine to the control valve. The air flows through a first port in the control valve to the actuator. Air leaving the actuator flows through a second port in the control valve and then back to the pilot valve through which it is exhausted. A pilot valve member initially limits air flow through the second port, but as the flaps are deployed, the second port is gradually opened and the first port gradually closed. The operation is reversed to retract the flaps. The pilot valve may be operated by a switch responsive to contact of the nosewheel of the aircraft with a runway. The pilot and control valve may be included in a single cylindrical body with their valve members rotatable about the axis of the body.