Abstract: An aircraft control comprises a mobile pedal and comprises a cylinder coupled to the pedal such that a displacement of the pedal according to at least a first direction reduces the volume of a first chamber of the cylinder. A control device comprises a fluid type bus system connecting two aircraft controls. Additionally, an aircraft is equipped with such a control device.

Abstract: A hydraulic apparatus configured to supply track-setting devices for producing a cross-country skiing trail; the apparatus comprising: a first inlet configured to receive a fluid; a first outlet and a second outlet configured to release two flows of fluid; a first hydraulic coupling motor having a second inlet, a third outlet and a first shaft; and a second hydraulic coupling motor having a third inlet, a fourth outlet and a second shaft; wherein the second inlet and the third inlet are connected to the first inlet, and the first shaft and the second shaft are integrally connected to each other, the third outlet being connected to the first outlet, and the fourth outlet being connected to the second outlet.

Abstract: A system and method for automatically adjusting a pressure within a variable volume of a hydraulic feed tube while the variable volume of the hydraulic feed tube is changing. Inputs are used to determine the appropriate pressure adjustments for the hydraulic feed tube, which is adjusted by a pressure reducing valve, wherein control of the pressure reducing valve is updated continuously by a control module.

Abstract: An apparatus includes a drive mechanism, a first cylinder comprising a first piston coupled to the drive mechanism, and a second cylinder comprising a second piston. The first cylinder includes a first fluid reservoir and a second fluid reservoir, with the first piston disposed between the first fluid reservoir and the second fluid reservoir. The second cylinder includes a third fluid reservoir and a fourth fluid reservoir, with the second piston disposed between the third fluid reservoir and the fourth fluid reservoir. The apparatus further includes a first fluid line coupling the first fluid reservoir to the fourth fluid reservoir, and a second fluid line coupling the second fluid reservoir to the third fluid reservoir. The first piston comprises a threaded portion disposed in a threaded aperture of the first cylinder.

Abstract: A steering control system includes a steering circuit, a primary control circuit and a redundant control circuit. The primary control circuit includes primary proportional control valves, and a primary pilot valve having a thermal bleed of pilot fluid to warm the primary pilot valve when not operating to control the steering circuit. The redundant control circuit includes secondary proportional control valves, and a pressure reducing valve having a thermal bleed orifice allowing fluid flow to warm the pressure reducing valve when not operating to control the steering circuit. The thermal bleeds may also flow past the proportional control valves to raise their temperatures. The circuits of the steering control system are contained in a single valve group housing.

Abstract: A slave cylinder includes a first input port provided to a first slave hydraulic chamber and which is connected to a master cylinder and is selectively cut off from the master cylinder by a first shut-off valve; a second input port provided to a second slave hydraulic chamber and which is connected to the master cylinder and is selectively cut off from the master cylinder by a second shut-off valve; a first atmosphere port formed in a first back chamber disposed in rear of the first slave hydraulic chamber and which moves together with a first piston; a second atmosphere port formed in a second back chamber disposed in front of the first slave hydraulic chamber and which moves together with a second piston; and a restricting means to restrict the second piston. The second atmosphere port is disposed in the vicinity of the restricting means.

Abstract: A user interface linkage system includes first and second user interfaces that are linked by a single hydraulic circuit. The system is configured to provide compensation for relatively slow changes in hydraulic fluid pressure due, for example, to temperature variations. The system is also configured to allow the user interfaces to be selectively unlinked from each other.

Abstract: What is disclosed is a drive mechanism, in particular for blanking and nibbling machines, comprising a hydraulic force transmitting element and a spindle drive for driving the force transmitting element, wherein a pre-tensioning means for pre-tensioning the force transmitting element is provided.

Abstract: The invention relates to a hydrostatic drive comprising a first and a second hydraulic pump (11, 12) and a dual-acting hydraulic cylinder (2). The dual-acting hydraulic cylinder (2) comprises a first working chamber (7) and a second working chamber (8). The first working chamber (7) is defined by a first piston surface (4) of a working piston (3) and the second working chamber (8) is defined by a second piston surface (5) of the working piston (3). The first working chamber (7) is connected to a first connection (13) of the first hydraulic pump (11) and a first connection (14) of the second hydraulic pump (12). The second working chamber (8) is connected to a second connection (16) of the second hydraulic pump (12). A second connection (15) of the first hydraulic pump (11) is connected to a hydraulic fluid reservoir.

Abstract: A pressure intensifier for generating a relatively large force includes a plurality of pistons driven in advancing and retracting directions. The pressure intensifier includes a rod selectively drivable into a cavity to amplify the force acting on one of the pistons. A valve limits fluid flow to control the rate of movement of one of the pistons.

Abstract: An apparatus comprises first (3) and second (5) force-activated actuators, each having a fluid displacer (7, 9) and force control lever (19, 21) coupled to the fluid displacer, a conduit (15) for transporting fluid between the fluid displacers to couple motion of the fluid displacers, and a force controller (17) responsive to the pressure of the fluid for controlling a force opposing displacement of a fluid displacer.

Abstract: A servoactuator (20) is operatively arranged to control the movement of an output member (21) in either of two directions in response to a command signal. The servoactuator includes an electric motor (25); a first transmission mechanism (34); a hydrostatic second transmission mechanism (35); a transfer mechanism (36) operatively arranged to selectively couple the motor output shaft to the output member either through the first transmission mechanism to impart a high-speed low-force drive to the output member, or through the second transmission mechanism to impart a low-speed high-force drive to the output member; at least one feedback transducer (29, 32); and a servo control loop (30, 33) closed about the motor, controller, transmission mechanisms, transfer mechanism, feedback transducer and output member for selectively controlling at least one of the position, velocity or force of the output member as a function of the command signal.

Abstract: The invention relates to a device for telecontrolling a function of drives for vehicles or machines. The device consists of at least two manual gearboxes which are arranged at a distance from the drive to be controlled, the gearboxes respectively having a double acting cylinder arrangement comprising two cylinder chambers which can be actuated in counterrotation for a hydraulic flow medium, in order to control at least one function of said drive.

Abstract: A servoactuator (20) is operatively arranged to control the movement of an output member (21) in either of two directions in response to a command signal. The servoactuator includes an electric motor (25); a motor controller (24); a first transmission mechanism (34); a hydrostatic second transmission mechanism (35); a transfer mechanism (36) operatively arranged to selectively couple the motor output shaft to the output member either through the first transmission mechanism to impart a high-speed low-force drive to the output member, or through the second transmission mechanism to impart a low-speed high-force drive to the output member; at least one feed-back transducer (29, 32); and a servo control loop (30, 33) closed about the motor, controller, transmission mechanisms, transfer mechanism, feedback transducer and output member for selectively controlling at least one of the position, velocity or force of the output member as a function of the command signal.

Abstract: A fan assembly comprising two fans (4, 10) for supplying combustible gases to two burners (5, 9) respectively. The flow parts from the first and second burners are combined in a common manifold. Temperature censor (6, 11) detect the temperature of the gases passing through each fan, and the speed of a particular fan is increased if the temperature sensor detects reverse flow of combustion gases.

Abstract: An electro-hydraulic actuator system (10 or 140) includes a hydraulic actuator (27) having a pair of fluid filled chambers (29, 30) and being operable to provide an actuator output (12) as a function of fluid pressures at the chambers. An electric-hydrostatic actuator (34 or 141) includes an electric motor (35 or 142) responsive to motor control signals for providing an output to a motor shaft (40 or 150), one or more pistons (56 or 166, 170) coupled to the shaft, and one or more hydraulic housings (92 or 160, 162) mounted on the motor and cooperating with the pistons for providing a pair of fluid cylinders (54 or 164, 168) respectively coupled to the fluid chambers at the hydraulic actuator. A solenoid valve (33) is connected between the cylinders, and is responsive to valve control signals for feeding fluid between the actuator chambers and thereby short circuiting the hydrostatic actuator cylinders.

Abstract: An electro-hydraulic power steering system comprising an elongated vehicle steering linkage rack with a rotatable steering gear in mesh with rack teeth and extending within an elongated power assist cylinder of a rack housing. A rack piston separates the power assist cylinder into first and second power assist working chambers filled with hydraulic fluid. An electric/hydrostatic steering assist module includes a hydraulic actuator cylinder with a linear drive screw extending lengthwise therein and journalled for bi-directional rotation and against axial displacement. An actuator piston is reciprocable but non-rotatable within the actuator cylinder and separates it into first and second hydraulic fluid filled actuating chambers. The drive screw is threadedly engaged with the actuator piston to produce bi-directional linear movement thereof as rotationally bi-directionally driven by a servo motor carried on the module.

Abstract: A primary pipe system includes a master cylinder with corresponding pressure sensor that produces a primary electrical signal. A secondary pipe system includes a working cylinder with a pressure sensor that produces a secondary electrical signal. The secondary pipe system generates a secondary pressure on the working cylinder as a function of the primary electrical signal. A computer continuously processes the primary and secondary electrical signals to transmit an electrical signal at a fixed frequency with a period that is divided into two intervals to an electromagnetic valve. During the first interval the electromagnetic valve is kept in a first operational position and during the second interval it is kept in a second operational position. The computer varies the intervals according to an algorithm for rapid actuation of the working cylinder.

Abstract: A hydraulic synchronizing circuit includes at least one master cylinder unit including a primary chamber, a secondary chamber, a piston and at least one piston rod, the piston having a primary effective surface and a secondary effective surface. The hydraulic synchronizing circuit further includes at least one slave cylinder unit including a primary chamber, a secondary chamber, a piston and at least one piston rod, the piston having a primary effective surface and a secondary effective surface. The master cylinder unit and the slave cylinder unit are arranged to be single-acting. The secondary effective surface of the master cylinder unit and the primary effective surface of the slave cylinder unit are substantially equal. A tank at least partially formed by the secondary chamber of the slave cylinder unit and containing a fluid is provided. A pump sucks the fluid from the tank. A first conduit operatively connects the tank to the primary chamber of the master cylinder unit via the pump.

Abstract: A rotationally pivotal motion controller pivotally interconnects two adjoining elements and controls the pivotal motion of a first of the two adjoining elements with respect to a second of the two adjoining elements. The rotationally pivotal motion controller comprises a housing having a wall which defines an axial cylindrical bore through the housing. The wall is adapted for attachment to a first of the two adjoining elements and the wall also has a longitudinal aperture therethrough which communicates with the bore. A hub assembly comprises a hub which is at least partially disposed within the cylindrical bore of the housing and is axially rotatable therein. The hub has a substantially central cylindrical core and at least one lobe extending radially from the core. At least one end cap is affixed to one end of the hub to retain the hub in a fixed, fluidically sealed, axial relationship within the housing. The hub and the housing together define at least one fluid retention cavity.

Abstract: A motion control mechanism of the oil pressure cylinder comprises an oil storing cylinder, a driving rod and a reversible motor. The oil storing cylinder is in communication with the oil pressure cylinder having a piston rod and is provided therein with a piston which is provided at one end thereof with a coupling portion. The driving rod is provided at one end thereof with a connection head engageable with the coupling portion of the piston and is further provided therein axially with a threaded hole engageable with a threaded rod which is fastened at one end thereof with an output shaft of the reversible motor. The piston is actuated by the driving rod to move back and forth within the oil storing cylinder so as to control the motion of the piston rod of the oil pressure cylinder.

Abstract: A double acting hydraulic system including a master cylinder and a slave cylinder. Each of two slave cylinder spaces has a nipple boring (12, 22), for a nipple valve (40, 50), with an internal section in a form of a seat (16, 26) cooperating with an end (41, 51) of the nipple valve. A sealing section (19, 29) in each nipple boring located outside the seat slidingly and sealingly abuts a sealing section (44, 54) of the respective nipple valve. There is an annular space between each nipple valve and nipple boring, between the seat and the sealing section; and a connecting channel (35) provides communication between the annular spaces. One of the nipple valves has a nipple channel (60) with one opening (61) into the corresponding annular space and a second opening (62) to outside the nipple boring; and a device (63) that cooperates with the nipple channel to prevent fluid flow from outside the nipple boring to the annular space.

Abstract: A second pressure intensifying cylinder subchamber is employed for moving a pressure intensifying piston toward the other side, and the necessity for a control valve with a throttle is thereby eliminated. The pressure intensifying piston is incorporated integrally into a fluid cylinder, and, hence, the fluid cylinder can be installed in an even narrow space. A main cylinder chamber communicates with a pressure intensifying cylinder chamber in the interior of the fluid cylinder, and it is therefore possible to prevent such a situation that a high-pressure fluid sprouts out. A structure of the fluid cylinder is thus simplified enough to reduce the costs, and the safety is improved.

Abstract: A gear shift device for gear boxes for vehicles, comprising at least one pair of mutually connected, double-acting hydraulic cylinders (1,2), where the pair consists of a master cylinder (1) and a slave cylinder (21). The master cylinder can be operated via a gear lever and the slave cylinder moves a mechanism which is connected to gear selector carriers in the gearbox. According to the invention each end section of the master cylinder's (1) piston (4) has an outer (54 or 55) and an inner (56 or 57) piston sealing ring which are arranged at intervals, calculated in the piston's longitudinal direction, and in these end sections there is provided a drilling (52 or 53) whose first end leads into the piston surface between the respective end sections outer and inner sealing rings (54, 56 and 55, 57 respectively), and whose second ends leads into the adjacent end face of the piston (4).

Abstract: A closed loop fully self-contained actuation system for converting a mechanical input motion into a mechanical output motion, which actuates a device such as a flight control surface on an aircraft, comprises an input actuator including a first fluid pressurizing means responsive to the mechanical input motion, and an output actuator including a second fluid pressurizing means, as well as a flexible fluid line extending between the first and second fluid pressurizing means to provide fluid communication therebetween. The second fluid pressurizing means is responsive to fluid flow through the fluid line, thereby initialing the output motion. The system is advantageous because it requires no hydraulic pumps, no accumulators, no reservoirs, and no dynamic seals or mechanical joints, permitting great reliability. The actuation system may be easily folded in conjunction with the apparatus on which it is employed, for compact storage.

Abstract: A load control device applicable on agricultural machinery in general and in particular on machinery used for direct planting, so that the working components in contact with the ground will maintain the same load constantly at all times for any ground profile condition. An oil-pneumatic device is provided with a fluid compressor connectable to the tractor's power take-off by a cardan shaft and an electromagnetic clutch that can be powered from the tractor's electrical system or by an independent source, including a compressor with its associated pressurestat which governs it in order to maintain the air pressure required by the circuit. The compressor supplies a tank of compressed air, to which is connected at least one hydraulic cylinder whose upper and lower chambers are each connected to intermediate air and oil collecting reservoirs.

Abstract: A hydraulic booster for a vehicle and more particularly an improved hydraulic booster with improved brake-relieving action, among other improvements.

Abstract: A hydraulic control system comprising master and slave pressure units having pistons and which are filled with fluid. The master piston is connected to a control lever, while the slave piston is connected to an object to be controlled such as a clutch lever on a marine engine. Hoses so interconnect the master and slave pressure units that movement of the control lever moves the master piston and causes fluid to act on the slave piston to cause the piston to move and thus move the clutch lever. A port is formed in the casing of one of the master or slave pressure units. This port is formed to allow communication between a reservoir of fluid and the casing. Given that chambers are formed on either side of the pistons within their respective casings, the port is so arranged that each of these chambers is placed in fluid communication with the reservoir at least once during the stroke cycle of the master piston (i.e., from begining to end and back to the beginning of the stroke).

Abstract: Methods of and apparatus for advancing a carriage utilize a displacement pump for displacing a selected quantity of fluid. The displacement pump is driven continuously by a motor to provide a series of fluid displacements which are accumulated in a hydraulic cylinder. A ram projecting from the hydraulic cylinder is coupled to the carriage and is advanced stepwise as the individual fluid displacements are accumulated in the hydraulic cylinder. The method and apparatus is especially useful for minimizing banding effects when advancing a carriage which supports a scanning device used in laser printers.

Abstract: A novel motor and method for converting rotary input motion to axial reciprocating motion of an output shaft in which input work and energy are transferred by creating unbalanced reaction forces with a motor driven unbalanced rotating mass as it acts on a pair of first pistons in direct communication with hydraulic fluid. The reaction forces created by the spinning unbalanced mass are converted to axial reciprocating motion by constraining the motion of the mass drive shaft, the supporting structure and the first pistons. A pair of second pistons, being integral with an output shaft, transfers oscillating pulses from the first pistons to a common output shaft where it can be applied to do work on an external system.

Abstract: This invention relates to a motion multiplier for use with an extendible boom forklift vehicle wherein a light-duty fork carriage is linked to the motion multiplier attached to a heavy-duty fork carriage to allow motion of the light-duty forks to translate to a multiplication of motion of the heavy-duty forks. The motion multiplier is a cylinder, piston and rod assembly which, when utilized between a light-duty fork carriage and a heavy-duty fork carriage, allows for movement of a particular distance of the light forks to be translated into movement of twice that distance by the heavy forks. The motion multiplier allows for a heavy-duty fork carriage to be superimposed upon and operated by a light-duty fork carriage without any need for disconnecting and reconnecting hydraulic systems.

Abstract: The present invention provides a pneumatically powered actuator having hydraulic control for both locking and controlling the velocity of an output rod without any sponginess. The invention includes a double-acting pneumatic actuator having a bore, a piston slidably engaged within the bore, and a control rod connected to the piston. The double-acting pneumatic actuator is mounted to a frame. A first double-acting hydraulic actuator having a bore, a piston slidably engaged within the bore,and a follower rod mounted to the piston is mounted to the frame such that the follower rod is fixedly connected to the control rod. The maximum translation of the piston within the bore of the first double-acting hydraulic actuator provides a volumetric displacement V.sub.1. The present invention also includes a second double-acting hydraulic actuator having a bore, a piston slidably engaged within the bore, and an output rod mounted to the piston.

Abstract: A hydraulic apparatus for remotely controlling the operative mode selector of a motor vehicle automatic transmission. The apparatus comprises a master cylinder having an input member operatively connected to the transmission operative mode selection or shift lever placed at the disposal of the motor vehicle operator, and a slave cylinder mounted on or proximate the transmission casing and having an output member connected to the transmission operative mode selector, the master cylinder and the slave cylinder being placed in fluid communication through flexible conduits such that each displacement of the master cylinder piston as a result of displacement of the master cylinder input member causes a corresponding displacement of the slave cylinder piston coupled to the slave cylinder output member.

Abstract: An adjustable rear view mirror, the mirror element of which is supported by a ball-and-socket-like joint, and can be adjusted by two elements that can be actuated by pressure medium. In order to use single-acting adjustment elements, a reset spring is associated with the two elements. This reset spring is disposed on an imaginary line that bisects the angle defined by the two adjustment elements and the ball-and-socket-like joint. This reset spring is expediently a compression spring that is disposed across from the two adjustment elements.

Abstract: A hydraulic driving system for motorcycle gear shift includes a primary cylinder combination, a secondary cylinder and a set of delivery conduits for handling hydraulic fluid connected therebetween, in which two primary cylinders with different diameters are oppositely formed in a hollow portion of a motorcycle handle and the two primary cylinders are respectively fluidically communicated with the secondary cylinder to reciprocatively and linearly move a gear rack and to drive the shaft of the gear shift by rotating a twist bar, formed on the handle, having an inclined-plane tongue alternatively actuating the two primary cylinders in the handle.

Abstract: A peristaltic motor is provided comprising a reciprocating slave piston adapted to be actuated by the progressive, sequential contraction of two aligned, resiliently deformable peristaltic tubes by a weighted roller such as a wheel of a heavy vehicle. The leading ends of both tubes, that is the ends first contacted by the moving roller, are connected to the slave cylinder, one on either side of the piston and the trailing ends of the tubes are connected to one another so that movement of the roller from the leading end to the trailing end of the first tube causes the hydraulic fluid therein to move down the tube and into the slave cylinder moving the piston through half a stroke. Movement of the roller in the same direction over the second tube, forces the hydraulic fluid into the other side of the slave cylinder to move the piston through the second half of the stroke. The piston is associated with means to utilize its movement such as an air compressor or a pump.

Abstract: Centering and cooling equipment for a hydraulic vibration generator, with a pulsation generator pressurizing a cylinder containing a movable piston, composed of a feed system and a flushing system. The feed system includes spring-loaded non-return valves connecting a fluid reservoir to feed pipes connecting the pulsation generator to the cylinder chambers, and operates to supply cool pressure fluid from the reservoir when pressure in the cylinder chambers falls below a predetermined level. The flushing system includes a control bush/control plunger unit, bush and plunger of which are respectively connected to the piston and cylinder or vice versa, the plunger cooperating with channels in the bush to connect either feed pipe to a return passage according to the off-center position of the plunger in the bush. This system operates to withdraw a quantity of pressure fluid, dependent on pressure and stroke, from the cylinder chambers with each piston stroke.

Abstract: A three-cylinder hydraulic system providing position feedback for controlling powered machinery is described wherein an operator moves a control handle and the various working elements of the machinery respond to follow the path of the control handle, the freedom of movement of which is limited by the ability of the machinery to respond. The system consists of a control station comprised of an assemblage of linkages resembling the machinery to be controlled. Associated with each movable element on both the control station and machine, and with each lever or switch on the machine, are double-acting hydraulic cylinders or rotary actuators. The three cylinders thereby associated with each particular working element and its actuation are connected hydraulically so that the control station cylinder hydraulically manipulates the cylinder that moves the lever or switch that actuates that working element on the machine.

Abstract: A load-controlling piston of the double-action type, dividing an associated cylinder into two compartments, is positionable by a hydraulic servomechanism comprising a block wherein a high-pressure supply port and a low-pressure discharge port communicate with a pair of pressure cylinders occupied by respective plungers which are hydrostatically linked with the piston through conduits connecting the compartments of the piston cylinder with respective pressure chambers of variable volume formed by the two pressure cylinders. Each plunger has an axial bore accommodating a valve stem with a tapering head which is surrounded with small clearance by a valve chamber communicating at one end with the discharge port and at the opposite end via an internal passage with a gap adjacent a plunger face remote from the corresponding pressure chamber.

Abstract: A control system for connecting a manually actuated lever to an arm of a fluid translating device that forms part of the drive transmission for a skid steer vehicle is disclosed herein. The connection between the lever and the arm is in the form of a hydraulic fluid connection that includes master and slave cylinder and piston assemblies with the master cylinder and piston assembly connected to the lever and the slave cylinder and piston assembly connected to the control arm. The opposite ends of the respective cylinders on opposite sides of the respective pistons are interconnected by fluid conduits to define first and second chambers and both pistons are biased to a centered neutral position.

Abstract: A system for powering a gas-sealed, flywheel-type turbine comprises a pair of pressurized storage tanks used alternately as a source and sink of Freon. A rotary valve, in a first position, directs liquid Freon from the first storage tank, functioning as a Freon source, to a boiler to produce super-heated Freon vapor. The super-heated vapor is used to directly drive the turbine, and the turbine exhaust vapor is converted back to liquid Freon in a condenser. The high pressure outlet of the turbine is used, via a capillary tube, to supply pressure for forcing the liquid Freon from the storage tank to the boiler. The condensed Freon is then directed, through the rotary valve, to the second storage tank functioning as a Freon sink. When the liquid Freon in the first storage tank is nearly depleted, boiling of the Freon is detected by a thermostatic bulb in thermal contact with the tank bottom.