Abstract: An anchoring device for anchoring a floating object to an anchor structure, including a first attachment suitable for being secured to the floating object; a second attachment for being secured to the anchor structure; a damping member for damping the relative motion between the attachments for securing the first attachment to the second attachment and including a slide chamber, a piston for sliding in the slide chamber according to a relative motion between the attachments and a damper for damping the sliding of the piston in the slide chamber; and a control unit including a measurement sensor for measuring the sliding of the piston; and a control board for varying the damping of the damper according to the sliding of the piston detected by the measurement sensor.

Abstract: A tip-over prevention system for dumping vehicles includes a tilt detector operably coupled to one of a cargo body and a chassis of a dumping vehicle. At least a portion of the cargo body is configured to be raised by a piston, and the tilt detector is configured to detect a current tilt. The system includes a fluid release valve placed in fluid communication with the piston which is activated in response to the tilt detector detecting a current tilt that exceeds a preset tilt limit. Activation of the fluid release valve releases a pressure in the piston causing the cargo body of the vehicle to lower.

Abstract: A hydraulic system (600) and method for reducing boom dynamics of a boom (30), while providing counter-balance valve protection, includes a hydraulic cylinder (110), first and second counter-balance valves (300, 400), and first and second control valves (700, 800). A net load (90) is supported by a first chamber (116, 118) of the hydraulic cylinder, and a second chamber (118, 116) of the hydraulic cylinder may receive fluctuating hydraulic fluid flow from the second control valve to produce a vibratory response (950) that counters environmental vibrations (960) on the boom. The first control valve may apply a holding pressure and thereby hold the first counter-balance valve closed and the second counter-balance valve open.

Abstract: A monitoring device includes a first pressure sensor that detects a first pressure value of a pressurized fluid in a first pipe, a second pressure sensor that detects a second pressure value of a pressurized fluid in a second pipe, and a detector that determines, on the basis of the first pressure value and the second pressure value, whether or not a piston has reached one end or the other inside a cylinder body.

Abstract: A microcomputer of a detector that constitutes part of a monitoring device calculates differential pressures (first differential pressure, second differential pressure) between a first pressure value detected by a first pressure sensor provided in a first tube and a second pressure value detected by a second pressure sensor provided in a second tube, and on the basis of the calculated differential pressure, determines whether or not a reciprocating motion operation of the piston is in an intermediate state between a normal state and an abnormal state.

Abstract: The present disclosure relates to a method for the control and/or the data acquisition of a crane, wherein at least one measuring device at the crane supplies one or more measured values for determining the position of at least one load lifting device, in particular a crane hook, wherein a calculation of the position of the load lifting device is effected on the basis of the one or more measured values of at least one measuring device and one or more data characterizing the stiffness of the crane. The present disclosure also relates to a crane controller and a crane for carrying out the method according to the present disclosure.

Abstract: An actuator includes a ram structure slidably mounted within a cylinder structure bore and defines with the cylinder structure a gap therebetween. A fluid passageway structure in the ram structure defines a path for fluid to flow through the ram structure and includes an outlet in a sidewall of the ram structure. A cushioning seal located between the ram structure and the cylinder structure can engage the ram structure and a cylinder cap during ram structure extension such that the seal substantially closes off a first portion of the gap extending from the seal toward an open end of the cylinder structure. The cushioning seal can move during ram structure retraction in a direction of ram structure retraction such that fluid flowing out of the ram structure sidewall outlet, when the outlet is in the gap first portion, flows between the seal and the cylinder cap.

Abstract: An electro-pneumatic actuator for a waste gate includes an electric actuator to impart linear motion to an actuator shaft, and a pneumatic chamber defining a passage extending therethrough, the actuator shaft extending through the passage, the pneumatic chamber being sealed with respect to the actuator shaft. A piston is disposed in the pneumatic chamber and arranged for movement in the pneumatic chamber, the piston being affixed to the actuator shaft such that the actuator shaft and the piston move together as a unit. There is a port into the pneumatic chamber for feeding a gas into the pneumatic chamber or exhausting the gas therefrom so as to exert a pressure force on the piston and thereby provide a pneumatic assist to the force exerted on the actuator shaft.

Abstract: The invention relates to an energy-efficient apparatus driven by compressed air and equipped with a dual piston function for tensioning, or clamping, or centering, or punching, or welding, or clinching, for use in body construction in the automotive industry. The apparatus is driven by a pressurized fluid, in particular by compressed air. It is shown how a significant amount of operating costs can be saved while, at the same time, conserving the environment and consuming a low amount of pressurized fluid, in particular compressed air. In addition, the pivoting angle of a toggle joint assembly and thus of an apparatus connected thereto, for example, a tensioning arm of a toggle tensioning apparatus, can be continuously adjusted in both directions while, at the same time, adjusting a sampling device using sensors, for example, microswitches, or inductive switches, or pneumatic switches, or limit switches.

Abstract: A pneumatic booster (40) disposed between a brake pedal (5) and a master cylinder (7) includes a cylindrical member (60) provided on an outer circumferential side of an output rod (58). A seal member (62) seals between an outer circumferential side of the cylindrical member and a cylindrical portion of a front shell, and an O-ring seals between the cylindrical member and the output rod. The cylindrical member causes a differential pressure between a negative pressure chamber (A) and an atmosphere chamber (C) to be applied to a valve body (46). One axial side of the cylindrical member is configured to cause an atmosphere pressure to be applied to the valve body by abutting against a cylindrical protruding portion of the valve body, thereby pushing the valve body with the aid of the differential pressure in the direction as a biasing direction of a return spring.

Abstract: An actuator displacement measuring system in an electro-hydraulic system for a construction machine is disclosed, which can detect an actuator displacement using the characteristics of an electro-hydraulic system. The actuator displacement measuring system includes controlling driving of an electric motor, determining whether the electric motor is driven, determining whether a set pressure value of a relief valve is larger than or equal to a measured pressure value of the hydraulic system if a displacement value of an actuator that is always detected deviates from a zero value of a reference position, setting the actuator displacement value to a previous value if a pressure value of the hydraulic system is larger than or equal to a pressure value of a relief valve and calculating the actuator displacement value using a rotating speed of the electric motor.

Abstract: An apparatus for compensating for fluid contraction in a hydraulic powered telescoping boom may include a monitor determining the elevation angle of the telescoping boom, a supply of hydraulic fluid, and a fluid control responsive to the monitor. The fluid control provides the hydraulic fluid from the supply to a hydraulic cylinder controlling extension of the telescoping boom when the elevation angle exceeds a predetermined threshold angle to compensate for thermal contraction of hydraulic fluid and thus prevent uncommanded boom retraction. A method in accordance with the invention is also disclosed.

Abstract: A hydraulic control system for a machine is disclosed. The hydraulic control system may have a tank, a pump, and a fluid actuator. The hydraulic control system may further have an accumulator configured to selectively receive pressurized fluid discharged from the fluid actuator and selectively supply pressurized fluid to the fluid actuator. The hydraulic control system may also have a pressure sensor configured to generate a signal indicative of a pressure of the accumulator, a charge valve, a discharge valve, and a controller in communication with the control valve, the charge valve, and the discharge valve. The controller may be configured to detect stall of the fluid actuator, to make a comparison of the pressure of the accumulator with a threshold pressure, and to selectively move the charge valve to charge the accumulator or move the discharge valve to discharge the accumulator during the stall based on the comparison.

Abstract: An oil control valve is disposed in fluid communication between an oil supply gallery and an oil control gallery of an oil control system. The oil control valve has a first position that prevents flow of oil from the oil supply gallery to the oil control gallery and permits flow of oil from the oil control gallery to a downstream drain line, and a second position that permits flow of oil from the oil supply gallery to the oil control gallery and prevents flow of oil from the oil supply gallery to the drain line. An oil bypass passage is disposed in fluid communication between the oil supply gallery and the oil control gallery, and is disposed to bypass the oil control valve. The oil bypass passage has first and second oil flow constriction regions, and an intermediate volume disposed between the first and second oil flow constriction regions.

Abstract: An apparatus for compensating for fluid contraction in a hydraulic powered telescoping boom may include a monitor determining the elevation angle of the telescoping boom, a supply of hydraulic fluid, and a fluid control responsive to the monitor. The fluid control provides the hydraulic fluid from the supply to a hydraulic cylinder controlling extension of the telescoping boom when the elevation angle exceeds a predetermined threshold angle to compensate for thermal contraction of hydraulic fluid and thus prevent uncommanded boom retraction. A method in accordance with the invention is also disclosed.

Abstract: A method for calibrating pneumatic actuators comprising a containment structure (2) in which a diaphragm (4) is mounted which delimits a variable-volume chamber (5) whose internal pressure may be varied, and a rigid rod (8) able to slide through the containment structure (2) and connected to the diaphragm (4). At least one connecting head (11) can be mounted on an external second end (10) of the rigid rod (8) for connecting to an element to be controlled, such as a crank of a turbo-compressor.

Abstract: A compressed-gas motor has a cylindrical inner chamber closed gas-tight at a first base surface, and a piston arranged so as to be movable along the cylinder axis in the cylindrical inner chamber. A first opening feeds a compressed gas into the inner chamber, and a second opening discharges a gas from inside the inner chamber. The openings are arranged in the cylinder casing of the cylindrical inner chamber, wherein the first opening is arranged between the second opening and the closed first base surface. The first opening is closable by a first piston part and the second opening by a second piston part. The compressed-gas motor has a resetting device which exerts a force on the piston in the direction of the first base surface of the cylindrical inner chamber if the second piston part does not completely close the second opening.

Abstract: An electronically controlled hydraulic system for variable actuation of the valves of an internal combustion engine is constructed for fast filling of the high pressure side of the system.

Abstract: An actuator assembly includes a housing, a piston disposed within a portion of the housing. The piston has a movable range along a working-axis, and separates a first volume and a second volume within the housing. The assembly also includes a biasing feature disposed within the second volume, where the piston is configured to engage the biasing feature within a first portion of the movable range, and configured to not engage the biasing feature within a second portion of the movable range.

Abstract: The invention demonstrates how energy saving working cylinders are loaded with fluid under pressure in order, for example, to power devices for tensioning (toggle joint tensioning apparatus), and/or compressing and/or jointing and/or stamping and/or embossing and/or punching and/or welding, if necessary, under the interposition of gearing parts such as guides, parallelogram gears, toggle joint articulations or the like, with the fluid supply being controlled in such a way during the no-load stroke (idle stroke) of the piston (4) that only the forces of inertia and/or weight and/or the forces of friction of moveable parts are overcome and pressure is not applied from the fluid until the power stroke of the piston (4).

Abstract: A method for controlling a boom assembly includes providing a boom assembly having an end effortor. The boom assembly includes an actuator in fluid communication with a flow control valve. A desired coordinate of the end effector of the boom assembly is converted from Cartesian space to actuator space. A deflection error of the end effector based on a measured displacement of the actuator is calculated. A resultant desired coordinate of the end effector is calculated based on the desired coordinate and the deflection error. A control signal for the flow control valve is generated based on the resultant desired coordinate and the measured displacement of the actuator. The control signal is shaped to reduce vibration of the boom assembly. The shaped control signal is transmitted to the flow control valve.

Abstract: The invention relates to a piston pump for a motor vehicle braking system having a housing section and a piston guided displaceably in the housing section. The invention further has an intake valve having a valve seat arranged on the piston. The valve seat is configured as a circular sealing edge. A spherical valve body of the intake valve seals against the spherical sealing edge.

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: Apparatus and methods for hydraulic valve actuation of engine valves are disclosed. An exemplary embodiment of the present invention may include a plurality of slave piston assemblies that impart motion to the engine valves, wherein the motion is operable to open and close the engine valves. A dual diameter master piston assembly may be used to drive the plurality of slave pistons. The dual diameter master piston assembly may be divided into two or more elements with, for example, a spring bias or a button and T-slot assembly to hold the two elements together.

Abstract: A power generating turbine includes a rotary shaft having an axis of rotation, a magnet supported by and spaced outwardly from the rotary shaft and a conductive coil. The coil located outwardly from the magnet and surrounds the magnet and the shaft, but is sufficiently close to the magnet such that rotary movement of said magnet induces current flow in the coil.

Abstract: In an actuator control device that controls an expansion/contraction operation of a hydraulic cylinder, when a main spool 52 is switched to a discharge position for discharging working fluid in the hydraulic cylinder, a back pressure chamber 7 communicates with a tank passage 13 via a first port 14, thereby opening an operate check valve 51, and as a result, the working fluid in the hydraulic cylinder flows into a return passage 4 from an actuator port 1 and into a pilot chamber 20 through a second port 15. A pilot spool 53 is maintained in a balanced position by the pressure of the pilot chamber 20, which is caused to act by a front-rear differential pressure of a control throttle 25, and the biasing force of a spring 22 housed in a spring chamber 21, and therefore the opening area of the first port 14 is controlled to and maintained at a fixed level.

Abstract: An electrohydrostatic actuator including an unbalanced area actuator whereby movement of an actuator piston causes a greater change in displacement on a first side of the actuator piston having a first area than on a second side of the actuator piston having a second area. The actuator includes a four-port, dual displacement hydraulic pump having a first pair of ports and a second pair of ports. If an axial piston pump is used, the pistons may be arranged in first and second rings of pistons arranged concentrically about a central axis. The pump has a port plate with a first pair of ports associated with the first ring of pistons and a second pair of ports associated with the second ring of pistons. At least one of the first pair of ports and at least one of the second pair of ports are connected to the first side of the actuator piston. At least one of the first pair of ports is connected to the second side of the actuator piston.

Abstract: The invention relates to a hydrostatic piston machine with a cylinder drum which is rotatably mounted in a housing. A plurality of cylinder bores are disposed in the cylinder drum, which bores can be connected via cylinder openings provided in the cylinder drum (6) to a first control opening (12) and a second control opening (15). The first control opening (12) is connected to a low-pressure line and the second control opening (15) to a high-pressure line. The first control opening (12) is connected via a first connection (38) and a second connection (39) to a channel (37), wherein the first connection (38) and, lying opposite, the second connection (39) are disposed at the first control opening (12).

Abstract: An actuator system including a receiving body defining a mounting bore, a inlet fluid channel, an outlet fluid channel and a connecting channel between the inlet fluid channel and the outlet fluid channel, a valve seat disposed within the connecting channel, and an actuator assembly connected to the receiving body, the actuator assembly including a sealing tip extending into the mounting bore, the sealing tip being adapted to sealingly engage the valve seat.

Abstract: A positioning system includes an actuator, valve (preferably pneumatic), position sensor and an electronic valve controller, integrated in a single unit. Continuously variable setpoints are possible within the range of operation. A preferred control circuit includes a signal converter, a ramp generator to smooth the shape of the command or target value signal applied, a position feedback sensor to report the actual position of the actuator, a controller, and a driver, containing an H-bridge, for controlling the pneumatic valve which feeds air into the actuator mechanism. Integration of all these components into a single unit shortens signal paths, improves resistance to electrical noise, and permits faster response time.

Abstract: An method for estimating actuator position includes the steps of receiving fluid pressure data signals from a plurality of fluid pressure sensors (31), receiving spool position signals from at least one spool position sensor (33), and receiving actuator position data signals from at least one actuator position sensor (35). Corrected flow rates to and from an actuator (21) are determined with each corrected flow rate being based on fluid pressure data signals, the spool position signals, and an error-correction factor, wherein the error-correction factor is a function of the fluid pressure data signals and the spool position signals. An estimated actuator position is determined wherein the estimated position includes a kinematic component and a dynamic component. Adaptive gain factors are applied to calibrate the estimated actuator position to the actuator position data signals from the actuator position sensor.

Abstract: A position control system is used for controlling a fluid operated cylinder having at least one fluid chamber defined by a piston located within a housing for movement between first and second end limits of travel. The system includes at least two electrically actuated proportional flow control valves connected to each port of the cylinder for selectively and proportionally controlling fluid flow into and out of the at least one chamber. At least one pressure sensor is provided for measuring fluid pressure with respect to each chamber. At least one discreet position sensor is located adjacent a midpoint of the cylinder for sensing a discreet centered position of the piston. A controller includes a program and is operably connected for controlling actuation of the at least two valves in response to pressure measured by the at least one pressure sensor and location measured by the at least one position sensor.

Abstract: A hydraulic valve actuation system has a hydraulic actuator connected with a valve in an engine. The hydraulic actuator has a boost pin enclosing a drive pin in a casing. The drive pin connects with and defines a valve lash with a valve stem of the valve. The hydraulic actuator applies and releases an actuating force through the drive pin to the valve stem that selectively opens and closes the valve during engine operation. The hydraulic actuator adjusts the valve lash during one or more rest periods. By adjusting the valve lash during the rest periods, the hydraulic actuator essentially adjusts the valve lash in response to one or more of the actual physical parameters of the valve during engine operation.

Abstract: A valve that keeps a electro-hydraulic servo valve (EHSV) controlled device such as a fuel metering valve or actuator at the last commanded position upon loss of input command in the EHSV is described. The valve fixes the position of the positioning device within a tolerance of the position the positioning device was at prior to the loss of the position command. Upon loss of the input position command, the valve moves from its spring-biased default position to a position that keeps the positioning device at a position within a tolerance band of its last commanded position as a result of the differential pressure created when the EHSV loses its input position command.

Abstract: Improved actuators and valve control systems, and methods for controlling actuators and/or engine valves, are disclosed. In addition to the inherent capability of timing control, the ability to provide continuous valve lift or stroke control greatly improves engine achieve fuel economy, emission and performance. The power-off state of the actuator is at the minimum stroke, from which an easy start-up can be directly executed. The minimum stroke is also very beneficial to achieve efficient low load operation. Even with continuous lift variation, the present invention is able to keep the spring force neutral or zero point in the center of a stroke, thus maintaining an efficient scheme of energy conversion and recovery through the pendulum action. When in compression braking or other high engine cylinder air pressure working mode, the invention is able to supply necessary force to open the engine valve.

Abstract: Actuators, and corresponding methods and systems for controlling such actuators, provide independent lift and timing control with minimum energy consumption, while supplying sufficient supplemental energy to overcome friction. In an exemplary embodiment, an actuation cylinder in a housing defines a longitudinal axis and having first and second ends in first and second directions. An actuation piston in the cylinder, with first and second surfaces, is moveable along the longitudinal axis. First and second actuation springs bias the actuation piston in the first and second directions, respectively. A first fluid space is defined by the first end of the actuation cylinder and the first surface of the actuation piston, and a second fluid space is defined by the second end of the actuation cylinder and the second surface of the actuation piston.

Abstract: A large-size manipulator comprises a boom made up of several segments and arranged on a vehicle frame. The boom is foldable and has a slewing track ring rotated about a vertical axis of rotation. The boom segments can be swiveled with respect to each other and with respect to the slewing track ring. A distant steering system includes a steering organ to operate the driving units and to set a desired position of the driving units and/or the boom segments and the slewing track ring. A control system includes a monitoring unit to ascertain a parameter that describes a disturbance condition of at least one boom segment. A determination unit determines the load that acts on a driving unit in opposition to the position set by the steering organ. The control system assures that the driving unit is controlled to minimize the deviation from the set position of the boom segments. Vibration of the boom segments will therefore be damped.

Abstract: A position determining system may include a hydraulic cylinder and a flow control device operatively connected to the hydraulic cylinder. A controller may be configured to supply an actuating signal to the flow control device. The controller may be configured to monitor a characteristic associated with the actuating signal, determine a hydraulic fluid flow rate in the hydraulic cylinder based on stored information relating the hydraulic fluid flow rate to the characteristic associated with the actuating signal, calculate a position of a component associated with the hydraulic cylinder based on the hydraulic fluid flow rate, and update the stored information when the determined position deviates from an actual position of the component.

Abstract: A swing cushion system of a work machine includes a directional flow device having a directional control member, a control device coupled to the directional flow device that outputs a signal to the directional flow device to shift the directional control member to dissipate energy in the fluid.

Abstract: A threaded nipple (26) at the closed end of a linear hydraulic motor (12) is received within a recess (82) in a frame member (78). Single clamp members, or individual clamp members (88), have recesses (92) that receive lower portions of the nipples (26). Bolts (94) extend through the clamp members (88) and screw into threaded openings in the frame member (78). This clamps the nipples (26) between the frame member (78) and the removable clamp members (88). End members (22) at the rod ends of the cylinders (12) include keys (66) that are received within recesses (80) formed in another frame member (76). Bolts (76) extend through the end member (22) and screw into threaded openings (84) in the member (76). A mounting frame has transverse mounting frame members (74, 102, 74?, 102?) that are used for mounting the drive assembly in an installation. The mounting frame members (74?, 102?) may have end portions (208, 210, 212, 214, 240, 242) that serve as cells in a trailer installation.

Abstract: A pressure releasing valve structure 36? is provided for a fluid operated device 10. The device has an orifice 42 constructed and arranged to be in fluid communication with a pressure chamber C. The valve structure includes a body 49 having first and second ends. A valve member 40 is provided at the first end of the body and is constructed and arranged to seal the orifice 42. A first spring 38 is associated with the first end of the body and is constructed and arranged to cause the valve member 40 to seal the orifice 42 under first pressure conditions in the pressure chamber C. A second spring 50 is associated with the second end of the body and is constructed and arranged to compress thereby reducing a force exerted by the first spring 38, permitting the valve member 40 to move to a non-sealing position to open the orifice under pressure conditions in the pressure chamber C lower than would be required absent the provision of the second spring.

Abstract: A hydraulic control circuit of a boom cylinder for a work machine, which, when controlling the supply and discharge of pressurized oil with respect to a boom cylinder, improves fuel efficiency, work efficiency in combined operations, and work efficiency and operationality in work of difficult boom operations, such as debris raking-up work and bumping work, etc. The hydraulic control circuit of a boom cylinder is provided with a first change valve for holding the boom control valve in the neutral position, a communication line for causing the head side oil chamber and the rod side oil chamber to communicate with each other, an opening and closing valve for opening and closing the communication line, and a pilot operation check valve that is changed to an unidirectional state where, although an oil flow from the head side oil chamber to the rod side oil chamber is permitted, a reverse flow is hindered, and a bi-directional state is permitted where the oil flows in both directions.

Abstract: A material eject system includes an ejector mounted to a bed of a vehicle which is movable between a rear end and a forward end of the bed for ejecting material from the bed. The ejector is powered by a cylinder having different fluid volumes depending on the direction of motion of the cylinder. A control circuit operates with the ejector motor to automatically move the ejector through eject and return cycles. Further, the control circuit detects different positions of the cylinder and automatically operates the cylinder at different speeds to maintain a constant motor and ejector speed throughout the material eject cycle.

Abstract: A threaded nipple (26) at the closed end of a linear hydraulic motor (12) is received within a recess (82) in a frame member (78). Single clamp members, or individual clamp members (88), have recesses (92) that receive lower portions of the nipples (26). Bolts (94) extend through the clamp members (88) and screw into threaded openings in the frame member (78). This clamps the nipples (26) between the frame member (78) and the removable clamp members (88). End members (22) at the rod ends of the cylinders (12) include keys (66) that are received within recesses (80) formed in another frame member (76). Bolts (76) extend through the end member (22) and screw into threaded openings (84) in the member (76). A mounting frame has transverse mounting frame members (74, 102, 74′, 102′) that are used for mounting the drive assembly in an installation. The mounting frame members (74′, 102′) may have end portions (208, 210, 212, 214, 240, 242) that serve as cells in a trailer installation.

Abstract: A pneumatic actuator system is provided which includes one or more piston-cylinder type actuators (14) intended for crust breaking operations at electrolytic alumina reduction baths. Each actuator (14) includes a working piston (21), and a piston rod (22) carrying a crust breaking working implement (17). A control circuit having a directional valve (24) is arranged to operate the actuator piston (21) in alternative directions. The control circuit includes air feed flow restrictions (26, 27), end position sensors (28, 29) and air feed shut-off valves (30, 31) for minimizing the pressure air volume needed for accomplishing complete working strokes of the actuator piston (21) at varying crust layer thickness.

Abstract: At a step of pressurizing a workpiece after reducing a speed of a piston rod at an end of a forward stroke of the piston rod by restrictively allowing compressed air to flow out of an exhaust-side pressure chamber, operation of a rapid exhaust valve is triggered by reduction of internal pressure of the exhaust-side pressure chamber to lower pressure than internal pressure of a pressurizing-side pressure chamber to thereby directly open the exhaust-side pressure chamber into the atmosphere through the rapid exhaust valve and rapidly reduce back pressure of a main piston remaining in the exhaust-side pressure chamber.

Abstract: Disclosed is a cushion cylinder device allowing high accuracy setting of a cushion operation start position. At the cushion operation start position of a driving cylinder, a first engagement member provided on a piston rod of the driving cylinder abuts a second engagement member provided on a piston rod of a cushioning cylinder, whereby the driving cylinder undergoes deceleration through cushion operation of the cushioning cylinder.

Abstract: A method and apparatus for operating a load lifting device to move a load and hold the load steady is disclosed. In the conventional arts, a lifted or lowered suspended load had a tendency to move from its desired position, as hydraulic fluid in the lifting system cooled, e.g. a stick slip condition. The present invention monitors a fluid pressure in the lifting system and compensates the fluid pressure to accommodate any pressure drop due to fluid cooling. Thereby, the load can be effectively held steady at a desired position, and the stick slip condition can be avoided.

Abstract: A safety device for a moving system with a drive in which a pneumatically operated piston, by linear movement in a cylinder, moves a transported object past a stationary part in at least one direction has the aim of generating a switching signal at every point of a through-opening when an obstacle is located between the moving object and the edge of the through-opening, regardless of the movement direction of the object and the geometrical construction of the through-opening. The cylinder has, at its ends, devices for measuring the pressure of the air flowing out of the cylinder in the movement direction of the piston, wherein a drop in the otherwise substantially constant pressure below a threshold value serves as a switching signal at least for switching off the system. The device is useful for safety purposes during the transport of objects, particularly when the objects form shearing edges with neighboring objects.

Abstract: A fluid actuator attaches a hinged safety device to a vehicle and pivots the hinged safety device between retracted and extended positions. The housing of the actuator has a base and a removable cover. A sub-assembly is attached to the base. The subassembly includes a generally planar base member with integral right cylinder, lever arm pivot support and stop posts. A piston slides in the right cylinder and forms a fluid chamber between the piston and a closed end of the right cylinder that is fed through a passage through the closed end of the cylinder. A lever arm is pivotally attached to the lever arm pivot support at one end for pivotal movement between retracted and extended positions, the lever arm extending over the cylinder and having a lip at an opposite end that is spaced from the right cylinder. A pivot arm engages the top of the piston at one end and the lever arm at an opposite end to transfer motion from the piston to the lever arm.