Abstract: An elongated fluid actuator arrangement includes a cylinder body comprising a first and second end portion. A piston body comprising a piston force area forming portion and a sleeve portion, which extends through said first and second end portions and exposes first and second outer section outside the cylinder body. A piston rod extends coaxially through said sleeve portion. The arrangement comprises a first and second extendable and contractible cover member each joined to the cylinder body and to the respective sleeve portion outer section.

Abstract: The double-acting pressure reducing cylinder (1) includes a cylinder shaft (71) which cooperates with a double-acting pressure reducing piston (2) connected to transmission elements (3) housed in a transmission casing (8), while a hollow pillar (13) whose ends are articulated is traversed by a rod tunnel and bears against the casing (8) to support the shaft (71), a tie rod (17) likewise articulated traversing the tunnel to clamp the cylinder shaft (71) to the hollow pillar (13), while lower centering elements of the cylinder (20) and upper centering elements of the cylinder (21) integrated with the transmission casing (8) in particular via a centering frame (22) allow the cylinder shaft (71) to move freely in parallel with its longitudinal axis but not in the plane perpendicular to the axis.

Abstract: The present invention regards an elongated fluid actuator arrangement comprising a first and second cylinder housing (3, 5) extending in a longitudinal direction (X), respective housing (3, 5) encompasses a first respective a second piston body (7, 9). The respective piston body (7, 9) divides the respective cylinder housing (3, 5) in a first and second cylinder chamber (11, 13). The arrangement (1) is adapted for connection to a valve member means (15) of a fluid supply device (17). A piston rod member (19) extending through said respective first and second piston bodies (7, 9). The first piston device (7) comprises a piston rod engagement and disengagement means (29), which is adapted to engage or disengage the first piston device (7) to/from the piston rod member (19), wherein an engagement area (A2), defined by an engagement zone between the first piston body (7) and the piston rod member (19), is larger than a cross-sectional piston area (A1) of the first piston body (7).

Abstract: The present invention provides a telescopic hoist comprising a series of telescopically arranged tubular sections wherein the tubular sections are made in nitrided steel.

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: An expansion device for doing work comprised of a housing including first and second selectively expandable sections defining an internal chamber which contains a chemical motor. Upon activation of the chemical motor, the first and second chamber are driven apart with sufficient force to allow the device to do work. The chemical motor is generally an irreversible reaction which causes the expansion device to be maintained in an expanded position.

Abstract: A plurality of drive motors are operated by fluid pressure for reciprocating the floor slats of a reciprocating floor conveyor. A switching valve alternately connects the forward and rear ends of the motors to pressure and return to reciprocate the slats. A forward and a rear control valve each has a closed position in which it blocks direct communication between the switching valve and all but one of the forward and rear ends, respectively. A four-way valve has ports communicating with pressure and return and with the pilot chambers of the control valves. The four-way valve connects one pilot chamber to pressure and the other to return to cause the conveyor to convey a load in a first direction. Reversal of the pressure and return to the pilot chambers causes a reversal of the conveying direction. At least one forward end and one rear end of the motors has an internal control valve positioned to open and close a connecting passageway between adjacent motor ends.

Abstract: An hydraulic piston and cylinder unit with a piston rod and first and second cylinders. The piston rod extends into the first cylinder, and the first cylinder extends into the second cylinder. The piston rod is connected to a first piston which divides the first cylinder into first and second chambers. A second piston, connected to the first cylinder, divides the second cylinder into first and second chambers. The second chambers of the first cylinder, and the first chamber of the second cylinder are in fluid communication such that an extension of the first cylinder causes a proportional extension of the second cylinder. A similar effect occurs during retraction of the cylinders.

Abstract: A hydraulic fluid Pressure-operated actuator comprises a first cylinder assembly having an output which operatively carries a second cylinder assembly such that an axial output force is effected from an output shaft of the second cylinder assembly, the output from the second cylinder assembly is a fast forward output stroke which is followed by a greatly increased high pressure force generated by the first cylinder assembly and effected through the output shaft of the second cylinder assembly.

Abstract: An object of the present invention is to provide a two dimensional drive system driven by fluid pressure. The drive system of the present invention comprises: a pair of X-guides; a pair of Y-guides; an X-rod whose each end is slidably attached to each Y-guide; a Y-rod whose each end is slidably attached to each X-guide; an X-piston section being provided at the midway of the X-rod; a Y-piston section being provided at the midway of the Y-rod; and a moving body having an X-chamber through which the X-rod is pierced and a Y-chamber through which the Y-rod is pierced, the X-chamber being divided into two subchambers by the X-piston section, the Y-chamber being divided into two subchambers by the Y-piston section. With this structure, the moving body is capable of moving in a plane by selectively supplying fluid to each subchamber.

Abstract: The piston rods (10, 12, 14) of three linear hydraulic motors (M1, M2, M3) are stationary and include fluid pressure passageways (40, 52, 42, 54, 44, 56) which direct fluid pressure into and out from working chambers (16, 34, 18, 36, 20, 38) on opposite sides of piston heads (22, 24, 26). Movable cylinder barrels (16, 18, 20) are connected to a load, e.g. floor members (FM1, FM2, FM3) of a reciprocating floor conveyor (FIG. 18). The outer ends of the piston rods (10, 12, 14) include balls and the balls include ports (46, 58, 48, 60, 50, 62) through which fluid pressure is delivered or removed. Associated with each port is a limit valve LV1, LV2, LV3, LV4, LV5, LV6. Limit valves (LV1, LV2, LV3) are pushed into an open position by a retraction of the motors (M1, M2, M3). Limit valves (LV4, LV 5, LV6) are pulled into an open position by extension of motors (M1, M2, M3). The limit valves (LV1, LV2, LV3, LV4, LV5, LV6) includes springs biasing them into closed positions.

Abstract: A telescopic pneumatic hoist has a flexible stationary hollow probe on its base arranged to unseat a check ball in the piston of the lowest intermediate stage when the piston is near the base. When such a condition exists, the probe closely interfits with the piston and has a radial port communicating with the underside of the piston. The probe connects at the bottom with a supply and exhaust passage which also communicates with the underside of the piston via a check valve controlled secondary passage.

Abstract: An article handling apparatus is disclosed which comprises two independently controllable fluid actuated drives. The first fluid actuated drive comprises a cylinder and a differential piston which defines a large chamber and a smaller chamber. Also, a control system is provided which maintains a differential pressure between the large and small chambers in each of several operating positions. The second fluid actuated drive is mounted to the movable member of the first drive, and the second drive is controlled by fluid lines leading respectively to the large and small chambers of the first drive.

Abstract: A plurality of piston heads (P1, P2, P3) are spaced apart along the length of a single piston rod (R). A separate traveling cylinder body (CB1, CB2, CB3) is associated with each piston head (P1, P2, P3). The traveling cylinders bodies (CB1, CB2, CB3) and the piston heads (P1, P2, P3) define first fluid chambers (1A, 2A, 3A) on a common side of the piston heads (P1, P3, P3) and a set of second fluid chambers (1B, 2B, 3B) on a common opposite side of the piston heads (P1, P2, P3). A separate fluid supply and return passageway is provided within the piston rod (R) for each of the working chambers (1A, 1B, 2A, 2B, 3A, 3B). Center members (C1, C2, C3) are secured within the hollow interior of the piston rod (R) and serve to divide the hollow interior into four axial sections (122, 124, 126, 128). The piston rod (R) includes first and second end members (RE1, RE2).

Abstract: Piston rods (60, 62) of three linear hydraulic motors (36, 38, 40) are connected at their outer ends (64, 68) to two spaced apart transverse frame members (10, 12). A cylinder housing (72) is driven back and forth along each pair of piston rods (60, 62). Three transverse drive beams (48, 50, 52) are provided. Each drive beam (48, 50, 52) is directly connected to an associated one of the cylinder housings (72). Three sets of floor slat members (1, 2, 3) are provided. Each set (1, 2, 3) is connected to an associated one of the transverse drive beams (48, 50, 52). The linear hydraulic motors (36, 38, 40) are operated for moving the floor slat members (1, 2, 3) in one direction, for advancing a load, and for retracting them in the opposite direction. Each cylinder housing (72) has four fluid chambers (82, 84, 86, 88). The first and third chambers (82, 86) are interconnected and the second and fourth chambers (84, 88) are interconnected.

Abstract: Piston rods (60, 62) of three linear hydraulic motors (36, 38, 40) are connected at their outer ends (64, 68) to two spaced apart transverse frame members (10, 12). A cylinder housing (72) is driven back and forth along each pair of piston rods (60, 62). Three transverse drive beams (48, 50, 52) are provided. Each drive beam (48, 50, 52) is directly connected to an associated one of the cylinder housings (72). Three sets of floor slat members (1, 2, 3) are provided. Each set (1, 2, 3) is connected to an associated one of the transverse drive beams (48, 50, 52). The linear hydraulic motors (36, 38, 40) are operated for moving the floor slat members (1, 2, 3) in one direction, for advancing a load, and for retracting them in the opposite direction. Each cylinder housing (72) has four fluid chambers (82, 84, 86, 88). The first and third chambers (82, 86) are interconnected and the second and fourth chambers (84, 88) are interconnected.

Abstract: Piston rods (60, 62) of three linear hydraulic motors (36, 38, 40) are connected at their outer ends (64, 68) to two spaced apart transverse frame members (10, 12). A cylinder housing (72) is driven back and forth along each pair of piston rods (60, 62). Three transverse drive beams (48, 50, 52) are provided. Each drive beam (48, 50, 52) is directly connected to an associated one of the cylinder housings (72). Three sets of floor slat members (1, 2, 3) are provided. Each set (1, 2, 3) is connected to an associated one of the transverse drive beams (48, 50, 52). The linear hydraulic motors (36, 38, 40) are operated for moving the floor slat members (1, 2, 3) in one direction, for advancing a load, and for retracting them in the opposite direction. Each cylinder housing (72) has four fluid chambers (82, 84, 86, 88). The first and third chambers (82, 86) are interconnected and the second and fourth chambers (84, 88) are interconnected.

Abstract: A servo-control system is provided for the steerable front wheels of a vehicle, particularly the steerable nose gear of an aircraft, at least the lower part of which having at least one wheel may rotate about its longitudinal axis. This system includes a high pass filter device whose input receives a signal containing at least a part representative of the oscillations about its longitudinal axis to which said lower part of said nose gear is subjected and whose output is connected to a device for subtracting the output signal of said high pass filter from said difference between said order and said signal representative of the real orientation, and the pass bank of said high pass filter covers the natural oscillation frequency of said lower part of the gear about its longitudinal axis.

Abstract: Piston rods of three linear hydraulic motors are connected at their outer ends to two spaced apart transverse frame members. A cylinder housing is driven back and forth along each pair of piston rods. Three transverse drive beams are provided. Each drive beam is directly connected to an associated one of the cylinder housings. Three sets of floor slat members are provided. Each set is connected to an associated one of the transverse drive beams. The linear hydraulic motors are operated for moving the floor slat members in one direction, for advancing a load, and for retracting them in an opposite direction. Each cylinder housing has four fluid chambers. First and third chambers are interconnected and the second and fourth chambers are interconnected. This arrangement provides adequate force producing area with a relatively small diameter cylinder housing. Fluid passageways are formed in the piston rods. Transfer valves are incorporated in end portions of some of the linear hydraulic motors.

Abstract: A piston type expander/prime mover utilizes a plurality of pairs of cylinders mounted on a rotatable cylinder support. Each cylinder has an open end and a closed end and each pair of cylinders has their open ends disposed in spaced, opposed relationship. A pair of pistons respectively cooperate with the pair of cylinders, and each piston has a connecting rod pivotally secured thereto and projecting through the open end of the respective cylinder. The two ends of the connecting rods are in turn pivotally connected to a lever arm which is secured to the movable element of a first unidirectional (over-running) clutch which has its stationary element secured to a stationary shaft. A first load transmitting element is secured to the rotatable element of the unidirectional (over-running) clutch. Valving is provided in the closed end of each cylinder to permit a charge of pressured gas to be introduced into such closed end as the respective piston approaches such closed end.

Abstract: Apparatus for producing a reciprocating oscillation of a power output shaft comprises a plurality of peripherally spaced cylinders disposed in generally tangential relationship to the periphery of a cylindrical fluid pressure chamber and connected at their inner ends to such fluid pressure chamber. The gas pressure in such chamber is regulated to maintain a selected value above ambient. Cooperating pistons in each of the cylinders are interconnected by connecting rods to a spoke-like rocker element which is freely oscillatable about the output shaft to which the housing defining the cylindrical fluid pressure chamber is secured for co-rotation. A flywheel mass is connected to the spokes of the rocker element. Inlet and exhaust valves are provided in a cylinder head mounted in the outer end of each cylinder and are operable by contact with the outer face of the respective piston.

Abstract: A piston-cylinder assembly for displacing a load through a long stroke consists of a rod, a piston slidable on the rod and by fluid pressure the piston is clamped to the rod, and a cylinder in which the piston is contained. By clamping the piston to the rod and introducing fluid into the cylinder, relative movement is caused between the piston and cylinder and the rod. When one assembly is used, the movement is intermittent but, by mounting two pistons on the rod, each piston being in a separate cylinder, and by controlling the flow of fluid, the movement is continuous.

Abstract: A pressure-medium-driven linear driving arrangement comprises a slide-shaped driving unit supported on a feed rack with a sliding curve. The driving unit comprising step-by-step elements in the form of piston-cylinder systems, which are controlled by a pressure medium via a rotary slide valve to produce a relative motion between the driving unit and the feed rack. The step-by-step elements each have a pivoted lever joined on one hand to the piston of the step-by-step element and on the other hand, joined to the slide housing, constituting self-centering feeding link driving elements.

Abstract: An improved hydraulic swing mechanism is disclosed for operation of the boom assembly of a backhoe or similar implement. The swing mechanism includes a pair of double-acting hydraulic motors pivotally interconnected between the backhoe frame and the backhoe boom assembly. A novel multi-position sequencing spool valve is disposed in fluid communication between the head ends of the hydraulic motors and a manually operated directional control valve which directs swinging movement of the boom assembly. A straight-forward valve control linkage operatively connects the sequencing spool valve with the boom assembly so that the spool valve is selectively operated as the boom assembly is pivoted through its arc of travel. An improved hydraulic cushioning circuit is provided in association with the sequencing spool valve, with the entire system providing improved operation of the boom assembly, with significant improvement in the hydraulic cushioning and torque characteristics of the system.

Abstract: Stack handling apparatus includes an input delivery section having two spaced apart conveyor segments operatively arranged to move equidistantly with respect to a centerline between the two conveyor segments. A stack formation section receives articles conveyed in a serial stream from the input delivery section and includes a carriage having a blade apparatus which is maintained at a generally constant predetermined angle as the carriage is transported in a closed loop transport movement path. Articles are assembled into batches on the blade apparatus, and each batch is transferred to door gate apparatus by relative linear movement. The door gate apparatus releases the batch for linear free fall movement to a turntable mechanism of a stack delivery section. The turntable mechanism alternately rotates 180.degree. after the receipt of each batch. Longitudinally extendable hydraulic assemblies are eccentrically connected to rotate the turntable mechanism.

Abstract: An improved hydraulic swing mechanism for a material handling implement, such as a backhoe, includes a multi-position, hydraulic sequencing valve for directing the flow of hydraulic fluid to hydraulic motors which rotate the swing tower and boom of the implement. A unique valve operating mechanism is provided for selectively repositioning the sequencing valve as the boom and swing tower are rotated in order to improve the operating characteristics of the swing mechanism. The valve operating mechanism includes a pivoted, frame mounted actuating arm connected with the sequencing valve by a lost-motion linkage, and flexible linkages connecting the actuating arm with the hydraulic motors of the swing mechanism.

Abstract: An improved hydraulic system is disclosed for a backhoe having a rotating boom operated by a hydraulic swing mechanism. The system includes a hydraulic rotary sequencing valve which is operatively connected with the swing tower which supports the rotating boom. During rotation of the swing tower and boom by the hydraulic motors of the backhoe, the rotary valve is operated to selectively direct pressurized fluid to the motors for improved torque characteristics. A hydraulic cushioning circuit is provided in association with the rotary sequencing valve so that hydraulic cushioning of the motors, and thus the boom, is effected during the approach of the boom toward its travel stops, eliminating the need for conventional cushioning mechanisms in the motors themselves, and improving overall performance of the machine.

Abstract: A unique hydraulic circuit is provided for converting rectilinear motion to rotational motion about an axis through the use of two pivotally mounted hydraulic motors. The hydraulic motors are pivotally interconnected between a pivoting member and a fixed member. A source of hydraulic fluid under pressure is directed to each hydraulic motor by a conduit system incorporating a flow control valve and a sequencing valve. The flow control valve selectively delivers fluid power to the hydraulic motors to rotate the pivoting member in one direction or the other. The sequencing valve senses the angular position of the two hydraulic motors and redirects the flow of fluid to the hydraulic motors in such a manner as to maintain the torque applied to the pivoting member relatively constant. The sequencing valve acts to redirect the flow of hydraulic fluid to the hydraulic motors so that only one of the hydraulic motors is pressurized at the end of the arc of swing of the pivoting member.

Abstract: Servoactuator includes a pair of double-acting linear actuators providing for 360.degree. controlled rotation of an output shaft. The rotary motion of the ouput shaft is employed to sequence high pressure fluid flow and return for the same to the respective ends of the respective actuators so that both actuators continuously develop output force except for end stroke points. Shimmy damping may also be obtained by a bypass-damping valve which comprises a shuttle movable to a first position by high pressure fluid for controlled operation of the servoactuator and to a second position by removal of the high pressure fluid to direct fluid flow between the respective actuators through a damping orifice.

Abstract: A rotator attachment for rotating a load handling mechanism on a lift truck includes a frame carrying an inner gear with external teeth and rotatable about a longitudinal axis of the truck. An outer gear surrounds the inner gear and has a greater number of internal teeth engaging the external teeth of the inner gear. A pair of double-acting hydraulic cylinders connected to the frame and outer gear are operated in sequence to drive the outer gear in a gyratory eccentric path with respect to such axis so as to rotate the inner gear and a connected load handling attachment about such axis. Control valving responsive to the position of the outer gear in its eccentric path is provided for operating the cylinders in the correct sequence for driving the outer gear. Relief valving is provided in conjunction with the control valving for preventing pressure-locking of the cylinders.

Abstract: A fluid operated linear actuator control system for drive arrangements of the type wherein two fluid operated linear actuators act upon a shaft at an angle with respect to each other for causing rotation thereof is disclosed. The control system includes a fluid pressure source including a reservoir means, fluid passages connecting the pressure source with each of the fluid operated linear actuators, and control means for communicating the first of the linear actuators with fluid from the pressure source and fluid from the other with the reservoir means to displace the drive arrangement through a first arc sector, and for changing-over the communication to communicate the reservoir with fluid from the one actuator and the other actuator with fluid from the pressure source causing displacement of the drive arrangement through a second arc sector, wherein one of the actuators is in a driving mode while the other actuator is in a floating mode.

Abstract: A rotator attachment for rotating a load handling mechanism on a lift truck includes a frame carrying an inner gear with external teeth and rotatable about a longitudinal axis of the truck. An outer gear surrounds the inner gear and has a greater number of internal teeth engaging the external teeth of the inner gear. A pair of double-acting hydraulic cylinders connected to the frame and outer gear are operated in sequence to drive the outer gear in a gyratory eccentric path with respect to such axis so as to rotate the inner gear and a connected load handling attachment about such axis. Control valving responsive to the position of the outer gear in its eccentric path is provided for operating the cylinders in the correct sequence for driving the outer gear. Relief valving is provided in conjunction with the control valving for preventing pressure-locking of the cylinders.

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: In a vehicle including a stick cylinder movable to change the attitude of a stick relative to a boom, and an implement cylinder movable to change the inclination of an implement relative to the stick, hydraulic circuit means are provided for serially connecting the cylinders so that as the stick cylinder moves the stick in one direction, discharge of fluid from the stick cylinder is used to actuate the implement cylinder to maintain substantially the same attitude of the implement relative to the ground. A flow divider is interposed between the cylinders to provide the desired degree of actuation of the implement cylinder in response to actuation of the stick cylinder. A dual pressure-responsive bypass valve provides a relatively high pressure relief to the implement cylinder when the implement cylinder is operated independently of the stick cylinder and provides a relatively low discharge path for the implement cylinder when operated in series with the stick cylinder.

Abstract: A compressed air-operated motor driven from a rechargeable compressed air supply tank. The motor has sets of symmetrically opposing cylinders having spring-biased air admission valves and containing drive pistons connected to a crankshaft. The supply tank is connected to the admission valves through respective pilot valves of a pair controlled by relay poppet valves alternately opened by a rotating cam driven by the crankshaft. The pilot valves control the delivery of compressed air alternately to two cylinder groups comprising alternately oppositely located cylinders, so that their pistons act to drive the crankshaft in a common direction by alternate power pulsations.

Abstract: An oscillatory electro-hydraulic system for a material handling bucket and including two hydraulic cylinder assemblies connectable with the bucket for tipping the bucket, and including a hydraulic pump and control valve and pressure relief valve and a reducing valve, all for directing flow to the respective cylinder assemblies. An electric system is interconnected with the assemblies and with one of the control valves, for controlling the flow of fluid to one of the two cylinder assemblies.

Abstract: Each of two drive wheels on a vehicle is independently driven by a wheel motor having four single acting hydraulic cylinders. Both wheel motors are supplied by a common engine driven pump. Two forward speeds are provided by a valve arrangement which can circulate the hydraulic fluid through all four, or only two, cylinders of each motor. Valves in a pair of valve units are shifted rapidly by camshafts and snap acting mechanisms to control the motor cylinders. Reverse drive is accomplished by a timing adjustment of the camshafts. The conventional gear differential, speed change gears and reversing gears are thereby eliminated.