Abstract: A device for locking a piston rod of a piston of an actuator is provided. An electrically actuatable electromagnet includes an armature rod, which is axially movable counter to a first preloading spring and on which two actuating elements are axially displaceably mounted between two stops of the armature rod. A second preloading spring is axially mounted between the two actuating elements. The actuating elements each include actuating contours, which are associated with latching mechanisms, via which the piston is mechanically fixable in a disengaged condition and in a engaged condition of the parking lock.

Abstract: The present system is directed in various embodiments to marine ladders comprising movement assistance for the transition from a deployed position to a stowed position and to assist in controlling the transition from the stowed position to the deployed position. In certain embodiments, the gas springs and associated pivot point brackets hold the deployed ladder biased in the deployed position with a biasing force that may be overcome by application of force by the user to initiate an automatic stowing process. The initial force to initiate the stowing process is provided by the force of water flowing against an aft-mounted ladder as a result of the boat moving forward. In the case of movement assistance from the stowed to deployed position, the user applies force to initiate the transition while the gas springs apply an opposing force that slows the transition for safety.

Abstract: The invention provides for a hydraulic cylinder position sensing and locking system that automatically maintains the position of a lock nut (36) that engages a plunger (16) on a hydraulic actuator such that if hydraulic pressure is lost, the lock nut prevents retraction of the plunger into the hydraulic cylinder (14). The hydraulic cylinder position sensing and locking system also provides for a position sensing feature that allows for the calculation of the axial stroke position of the plunger based on rotary movement of the lock nut. In addition, the invention provides for a synchronous hydraulic cylinder position sensing and locking system and methods of using both the hydraulic cylinder position sensing and locking system as well as the synchronous hydraulic cylinder position sensing and locking system.

Abstract: Provided is a shock absorber, which has a cylinder filled with a fluid, a piston valve dividing the cylinder into a rebound chamber and a compression chamber, and a piston rod extending to the outside of the cylinder in a state of being connected to the piston valve. The shock absorber includes: a free piston which divides the compression chamber into an upper chamber and a lower chamber in such a state that the piston rod vertically passes through the free piston, and forms a vertical passage such that the upper chamber and the lower chamber are connected to each other; and a support which is connected to the piston rod, with a larger diameter, increases a pressure of the upper chamber by locally tightly contacting and ascending the free piston from below during a rebound stroke of the piston rod, and forms a horizontal passage connected to the vertical passage.

Abstract: A device for actuating a locking mechanism, in particular for actuating a parking lock of a vehicle having an automatic transmission. The device comprises a piston which axially moves, a retaining device which is self-activating when the piston is in an axial position in which the locking mechanism is open to hold the piston in the axial position in which the locking mechanism is open, and an actuating device for actuating a release element, which deactivates the retaining device. To hold the piston in an axial position in which the locking mechanism is closed, the retaining device is self-activating, and can be deactivated to enable the piston to move, starting from the axial position in which the locking mechanism is closed, to the axial position in which the locking mechanism is open.

Abstract: The present disclosure relates to a chain drive assembly for a work machine, in particular for a crawler-mounted crane or a crawler excavator, having a drive crawler track, at least one displaceably supported sprocket wheel, in particular a guide wheel or idler wheel, and at least one tensioning device to tension the crawler track, wherein at least one abutment is provided which bounds the displacement of the displaceably supported sprocket wheel. The present disclosure further relates to a work machine, in particular to a crawler-mounted crane or a crawler excavator, having such a chain drive assembly.

Abstract: A hydraulic fluid actuated equipment leveling assembly incorporating a plenum having adjustment ports; an input channel opening the plenum; a disk valve operable for opening and closing the adjustment ports; telescoping and hydraulic ram actuated equipment support pedestals; hydraulic lines spanning between the plenum's adjustment ports, and the pedestal's hydraulic rams; and fluid displacing plungers connected operatively to the hydraulic lines for adjusting the hydraulic line's interior volumes.

Abstract: A length-adjustable piston cylinder unit comprises a casing; a guide and sealing unit; a piston rod; a piston; a first interior portion; a second interior portion which faces away from the first interior portion; an adjustment valve; a guide sleeve which is arranged for displacement on the casing, the guide sleeve being secured to the piston rod at a sleeve end and comprising at least one latch opening which is spaced from the sleeve end along the central longitudinal axis; and a latch sleeve arranged on the guide sleeve, the latch sleeve comprising a latch protrusion for engagement into the latch opening, with the latch protrusion of the latch sleeve being arrangeMc in the latch opening of the guide sleeve for arranging the piston cylinder unit in a secured position so that the displaccability of the guide sleeve connected with the piston rod relative to the casing is blocked.

Abstract: A length-adjustable piston cylinder unit comprises a casing which is filled with a fluid and has a central longitudinal axis; a guide and sealing unit which seals off the casing at a first end; a piston rod which is guided through the guide and sealing unit out of the first end of the casing in a sealed manner; a piston which is connected with the piston rod and is guided in the casing in a sealed manner; a first interior portion which is bounded between the piston and the guide and sealing unit; a second interior portion which is bounded by the piston and faces away from the first interior portion; an adjustment valve arranged in the piston for optionally connecting the two interior portions to each other; a guide sleeve which is arranged for displacement on the casing and is concentric to the central longitudinal axis, the guide sleeve being secured to the piston rod at a sleeve end and comprising at least one latch opening which is spaced from the sleeve end along the central longitudinal axis; and a latch

Abstract: A pneumatic actuator is provided for an active hood and includes, but is not limited to a cylinder and a piston, which is movable in the cylinder between a lower terminal position, in which the volume of a chamber delimited by piston and cylinder, which may be impinged using compressed gas, is minimal, and an upper terminal position, in which the volume of the chamber is maximal. The piston is lockable in the lower terminal position by a detent body engaging in first recesses of the cylinder and the piston. A slider is displaceable by impingement using the compressed gas out of an idle position, in which it fixes the detent body in the first recesses, into a triggering position, in which a second recess of the slider overlaps with one of the first recesses and is capable, together with a single one of the first recesses of accommodating the detent body.

Abstract: A pumping system and related methods involving an outer chamber and an inner chamber extending between two endplates, wherein the circumference of the inner chamber may be adjusted via a plurality of ribs and linear motors.

Abstract: Disclosed is an adjusting device for raising a hinged lid from a lowered, closed position into a raised, open position, especially for a motor vehicle, with a cylinder closed at one end, a piston, which divides the interior space of the cylinder into a first working chamber and a second working chamber, and which is installed with freedom to move axially back and forth in the cylinder, a piston rod, attached to the piston, the rod extending axially through the first working chamber and projecting through a seal to the outside, one or more flow connections connecting the first working chamber to the second working chamber, and a first adjusting element and a second adjusting element, wherein the first and second adjusting elements are designed to telescope into and out of each other and have guide devices, which make it possible to open the hinged lid into a partially opened position or into a completely opened position.

Abstract: A hydraulic actuator is provided for supporting a load. The actuator includes a cylinder, a lower end closed by a base, and an annular side wall connected between the base and the upper wall. A piston is disposed partially within the cylinder, and includes a rod extending through the upper end of the cylinder, and a piston head that defines a hydraulic chamber with the base. A cylinder chamber is disposed between the base and the piston head and communicates with a fluid source and a fluid return to correspondingly extend and retract the piston. A support member is connected to the cylinder wall, and can be raised to support a tilt saddle member between the piston rod and the load after the piston has been extended.

Abstract: The invention concerns a pneumatic and/or hydraulic actuator. The pneumatic and/or hydraulic actuator is one in which the run of a driving shaft, which is pneumatically operated by a piston, can vary on the basis of the insertion in the body of the actuator or at least one cylinder, so that the body of the cylinder forms a barrier along the run of the driving shaft causing the stoppage of the shaft itself.

Abstract: A hydraulic motor is equipped with an output shaft (2), a cylinder (4) arranged around the output shaft and receiving a plurality of pistons (6) expanding with the fluid pressure, a diagonal plate (7) that contacts the plurality of the expanding pistons (6), thereby to exert rotational force to the cylinder (4), a brake disc (21) disposed outside the cylinder (4) to rotate together therewith, a motor casing (11, 12) receiving the cylinder (4) and the brake disc (21), a brake driving device (25) that presses an outer periphery of the brake disc (21) on an inner peripheral surface of the motor casing (11, 12) to brake the brake disc. A first chamber (14) and a second chamber (15) are defined in the motor casing (11, 12) by the brake disc (21) and a communicating passage (30) formed bypassing the brake disc (21) communicates the first chamber 814) with the second chamber (15).

Abstract: A piston rod is formed in a diameter smaller than an inner diameter of a hollow cylinder. The piston rod is inserted in the cylinder so as to be relatively movable in an axial direction of the cylinder. A locking mechanism comprises a first surface provided on the inner surface of the cylinder, a plurality of second surfaces arranged in an axial direction of the piston rod and parallel to one another, and a locking member. The first surface is so inclined that the inside diameter of the cylinder gradually increases toward one end of the cylinder. Each second surface is so inclined that the diameter of the piston rod gradually increases to the one end of the piston rod. The locking member is held between the first surface and any one of the second surfaces to lock relative movement of the piston rod with respect to the cylinder.

Abstract: A handling equipment of the swingable arm type comprises a double acting cylinder within whose chamber a main piston is sealingly mounted, which is slidable owing to the selective delivery of fluid under pressure at opposite zones of the chamber, which is connected to a rod associated to the arm with a toggle joint. The equipment comprises a device for controlling the oscillation of the arm, including: a cavity of the rod having a nut screw, a screw member with a threaded shank in engagement with the nut screw, a rotatable head opposite to the rod and not slidably mounted with respect to the cylinder, and means for controlling the rotation of the screw member, associated with its head in order to brake the rotation of the screw member following to an anomalous condition in the feeding of fluid under pressure to the chamber of the cylinder.

Abstract: A linear positioning apparatus has a positioning actuator assembly including a cylinder and movable piston to be used for moving a workpiece or a moveable worktable along a rectilinear path or thrust axis. The apparatus includes at least one stop member adjustably mounted on a support such as a plate or hub. To stop the worktable at a selected stop point, each stop member can be positioned to engage an object, for convenience referred to herein as a bumper, that is connected to the moveable worktable to halt movement when the correct position has been reached. The apparatus includes means such as an actuator operatively associated to provide relative aligning movement between the stop member and bumper for placing the bumper and a selected one of the stop members in alignment with each other. The support for the stop member, e.g., a plate or hub, includes a bore or passage that extends entirely through it for each stop member so that each stop member can project out through both sides of the support.

Abstract: A self-locking cylinder capable of restraining substantially infinite force including: an angular or conical surface; a locking part; a release part; a force surface for establishing locking forces; a plurality of cylindrical or spherical parts such that the mechanism is capable of moving and locking and releasing JAW means at more than one discrete point with a maximum of one motor means operatively attached to each of said JAW means.

Abstract: A ram cylinder piston stroke stop is disclosed, including a pair of opposed piston shaft gripping members each formed in an extruded shape along an axis with an integral extruded axially open spring end receiving socket. A spring includes opposed ends that are engaged within the spring end receiving sockets.

Abstract: A fluid pressure cylinder has a lock mechanism in which its entire structure is simple. Also, its assembling operation and maintenance are easy. The lock mechanism to be assembled to a body of a cylinder includes a fulcrum pin for immovably supporting a lock plate in its axial direction. A spring biases the lock plate in its tilting direction around the fulcrum pin. A returning pressure chamber is provided on the side in which the lock plate is tilted by the biasing spring and applies a fluid pressure to the lock plate against a force of the biasing spring by supplying a pressurized fluid. A sleeve is fitted over a piston rod of the cylinder for forming an inner peripheral wall of the returning pressure chamber. A pressure receiving member for air-tightly sealing a space between the lock plate and an outer peripheral surface of the sleeve and between the lock plate and an inner peripheral surface of the returning pressure chamber is mounted to the lock plate closer to the returning pressure chamber.

Abstract: A rod clamp device having a clamp sleeve and a cam member spring biased axially in a direction to actuate the clamp sleeve to a clamp condition, and a clamp release piston that is operable through a mechanical force amplifying mechanism to move the cam member in opposition to the spring to release the clamp sleeve. The clamp release piston is operated in response to fluid pressure to produce a force correlative with the fluid pressure and the clamp release piston moves an annular ramp to force a plurality of ball elements between a thrust surface on an end of the cam ring and a stationary thrust surface and move the can ring axially in a direction to recompress the spring.

Abstract: The present invention provides an actuator controlled by an electro-hydraulic servovalve with a failfixed operation upon the loss of electrical power to the servovalve. A lock valve has apertures therethrough with friction pads therein for locking the actuator in position upon loss of the electrical power.

Abstract: The invention relates to a lockable telescopic device (1) which includes a cylindrical tube (10) and a piston rod (3). The piston rod (3) includes an expandable locking device (60) which, when active, forcibly abuts a part of the inner wall of the tube (10). The expandable locking device (60) includes two sleeves (61, 62) which accompany movement of the piston rod (3) in the longitudinal direction of the device (1). The piston rod (3) and the tube (10) are locked against relative movement by rotating the sleeves (61, 62) relative to one another with the aid of a lever (51) mounted on the piston rod. The invention also relates to the use of the lockable telescopic device in conjunction with so-called engine shelves.

Abstract: There is disclosed a shoring device for holding shoring boards against the walls of a trench. The shoring device is equipped with a locking mechanism to lock the device in an extended position in order to prevent the trench walls from collapsing. The shoring device includes a cylinder, a piston, and a piston rod with a rectangular cross-sectional geometry. The cylinder has an inlet for introducing a hydraulic fluid which upon entry into the cylinder causes the piston to slide within the cylinder, and the elongated piston rod to extend radially outwardly from the cylinder. In this extended position, the shoring device holds the shoring boards tightly against the walls of the trench. Upon retraction of the piston rod back into the cylinder, a cylinder end cap acts as a scraper, removing dirt and other particles from the surface of the rectangular piston rod.

Abstract: The invention relates to a master cylinder comprising a body (12) comprising a bore (14) in which slides, in leaktight manner, at least one piston (16, 18) movable between a rest position and at least one working position and defining at least one pressure chamber (20, 22) connected to an application fluid system, the piston (18) having a peripheral groove (44). According to the invention, a finger (42) actuated by an external mechanism (46) is capable of entering the groove (44) so as to lock the piston in one of its positions.

Abstract: The rodless cylinder includes at least a cylinder tube and a piston, but it has no piston rod that is indispensable in the conventional cylinders. The article carrier is connected via the piston yoke to the piston and movable with parts and jigs placed thereon as the piston moves along the cylinder. At least one rod is fixed relative to the cylinder tube to extend in parallel with the direction in which the piston and hence the carrier moves. The sensor is provided to be movable along the rod as the piston moves. The sensor has a moving member movable along the rod as the piston moves within the cylinder tube, for detecting a current position of the piston in accordance with relative positional relation between the moving member and the rod. With such arrangements, the rodless cylinder as a whole has a higher rigidity against heavy load, and also the piston can be accurately positioned to stop at a desired position in its stroke.

Abstract: The positively acting mechanism comprises a jack (2) with a rod (10) connected, at one of its ends, to a member whose actuation or retention it ensures, and, at its other end, to a thrust piece (16), on which a spring (18) comes to bear, in order to actuate or retain the member. An axle (25) parallel to the rod (10) of the jack is rotatably mounted in a housing (14) fixed relative to the body (3) of the jack (2) and has a threaded part (26) in engagement with a nut (34) forming an engagement fork for the thrust piece (16) of the rod (10). The axle (25) has an end part (30) engaging with a tool allowing the axle (25) to be set in rotation remotely. It is thus possible, in the event of failure of the jack, to rotate the axle (25) and displace the rod (10) of the jack (2) in the direction of release of the mechanism.

Abstract: A hydraulic actuator comprising a cylinder formed with an axial cylinder chamber, a main piston provided in the cylinder chamber and dividing the chamber into a first chamber and a second chamber and further formed with a locking chamber, an annular locking groove formed in the cylinder, a locking member cooperating with the annular locking groove to lock the main piston in a predetermined position, the locking member movable between an unlocking position and a locking position, a locking-unlocking piston for moving the locking member into the locking and unlocking positions, and a pressure introducing passageway for selecting the first or second chamber that is higher in pressure and introducing the higher pressure in the selected chamber into the locking chamber of the main piston. The locking-unlocking piston is moved by the pressure introduced by the pressure introducing passageway to move the locking member into the locking and unlocking positions.

Abstract: Provided is an improved fluid operated clutch control system having a latch member operable to lock the clutch in a selected condition of engagement or disengagement when the fluid pressure falls below a predetermined minimum value. In one embodiment a system (100) is provided in which a latch member (26) is controlled by fluid pressure in a channel (36) in a stationary wall housing (10). In another embodiment, a system (200) is provided in which a latch member (62) is controlled by the combination of fluid pressure sensed by a sensor (64) and the energization and de-energization of a solenoid (60) and, in yet another embodiment, a system (300) is provided with a latch member (62) that is controlled by the energization and de-energization of a solenoid (60).

Abstract: The locking device may either be used with a conventional liftgate support or incorporated into the design of the liftgate support, to retain a hatchback-type door of a vehicle in an open position. The locking device of the present invention is for use with a liftgate support to retain a hatchback-type door in an open position even in cold weather or after the liftgate support has worn out. The liftgate support includes a housing cylinder and an elongated piston rod. The elongated piston rod is slidably positionable relative to the housing cylinder, one end of the elongated piston rod being received within the housing cylinder. The locking device is secured to the housing cylinder by two-sided tape proximate to where the elongated piston rod is received by the housing cylinder.

Abstract: The present invention is directed to a self-adjusting servo mechanism (10). The servo pin (30) presented from the servo mechanism (10) will protract sufficiently to effect operative engagement of a friction band assembly (13) with a rotating member (18) in a planetary gear set--even though the required axial displacement of the servo pin (30) during such protraction may exceed the axial displacement through which the servo pin (30) was previously retracted. The servo mechanism (10) is incorporated in a housing (20). The housing (20) presents a socket cavity (24) within which an actuating piston (33) is received for axial displacement.

Abstract: A fluid cylinder assembly comprising a fluid cylinder having ports disposed at opposite ends thereof communicable with a source of fluid under pressure, a piston disposed in said cylinder having a first rod section extending through an end of said cylinder, extendable and retractable relative to said cylinder, the first piston rod section having an axial bore, a second piston rod section having a guide portion disposed in the axial bore of the first piston rod section and axially displaceable relative the first piston rod section, and means for detachably locking the first piston rod section to the second piston rod section.

Abstract: A brake locking mechanism of the anti-theft type for use with an automobile vehicular brake system having one or more fluid operated brakes, a master cylinder and an actuator for reciprocating a piston in the cylinder to apply and release the brakes. The locking mechanism has a housing adapted to fit between the master cylinder and the actuator, means such as a ratcheted rod within the housing for reciprocating the piston responsively to the actuator, and means such as a pawl operatively associated with the ratcheted rod for locking the reciprocating means with the piston in the brake applying position. The locking means is remotely controlled from a keyed or combination lockable control mechanism located in the driving compartment of the vehicle which may be mechanical or electronic.

Abstract: A pneumatic cylinder having an elongated cylinder member, a reciprocally movable piston, transfer means for transferring reciprocal movement of the piston to a work piece and a brake mechanism associated and movable with the transfer means for creating a braking force between the transfer means and a portion of the cylinder member. The brake mechanism includes a first brake surface connected with the transfer means, a second brake surface formed by an exterior surface portion of the cylinder member and a brake actuation mechanism for selectively causing movement of the first and second brake surfaces into braking engagement with one another.

Abstract: The invention disclosed herein is a cyclic power mechanism including means providing for a variable dwell between cycles of the mechanism. The mechanism produces energy during each cycle and stores the energy of each cycle for consumption. The variable dwell between cycles is terminated and a new cycle is initiated upon the consumption of a preestablished portion of the stored energy. A preferred embodiment of the mechanism is a free piston engine operation on an Otto cycle. The piston of the engine is restrained after each combustion cycle as the energy of that combustion is stored for use. When a preestablished portion of the stored energy has been consumed, the piston is released and forced into another compression and combustion cycle for further storage of the combustion energy.

Abstract: A hydraulic ram for use in thrust-jacking of tunnel linings comprises a cylindrical outer member, a cylindrical inner member reciprocable within the outer member, and an extension member reciprocable within the inner member. A two-part clamping ring is provided for releasably locking the extension member to the inner member. An auxiliary drive is provided for retracting the extension member rapidly within the inner member. The auxiliary drive may be a mechanical spindle drive, or a hydraulic drive having an auxiliary piston reciprocable within an axial bore formed in the extension member. The clamping ring comprises spring means for urging the parts of the clamping ring in to the closed position, and piston-and-cylinder means for urging the parts of the clamping ring apart, against the biasing force of the spring means, to open the clamping ring.

Abstract: A temperature sensitive locking mechanism is provided for a fluid pressure actuator which will hold the shaft of the actuator in a spring compressing position until the occurrence of a pre-selected temperature in the vicinity of the actuator. Locking threads are provided on the exterior of the actuator, and a latching collet, having a plurality of peripherally spaced, internally threaded, latching arms cooperates with such threads and prevent movement of the actuator shaft by abutting a surface of a stop block which is in abutment with the actuator shaft. The radial faces of the threads are sufficiently angled so as to exert an outwardly directed camming force on the collet latching arms to permit the release of the latch under the axial forces produced by the spring bias on the actuator shaft. The collet latching arms are forcably retained in locked position by an encircling spring wire, the ends of which are connected by a fusible link.

Abstract: Tractor front loaders have sometimes been provided with struts enabling them to be locked in raised position. These struts have had to be moved bodily between operative and inoperative positions. To avoid the need for bodily movement, the struts are made telescopic and are pivotable on loader support frames fixed to opposite sides of the tractor. Loader booms, and the rams of ram-and-cylinder assemblies for pivoting the booms, are pivotable on the support frames in known manner. The struts comprise inner and outer channel sections and are pivotable between retracted inoperative positions in which they are secured to the support frames and extended operative positions in which they are secured in contact with the adjacent ends of the cylinders of the extended assemblies.

Abstract: In the illustrative embodiments described, a pneumatic spring includes selectively releasable structure, located in part at the outer end of the piston rod and in part at the corresponding end of the cylinder, for retaining the piston rod at or near its innermost position within the cylinder. The retaining structure carried by the cylinder preferably constitutes a sleeve surrounding the piston rod, and the structure carried by the piston rod may include projections for coacting with shoulders on the sleeve. Alternatively, the sleeve and piston rod may be formed with cooperating recesses for receipt of an external pin-like securing bracket.

Abstract: A pneumatic spring having a cylinder and a piston rod biased axially outward of the cylinder by compressed gas in the cylinder cavity may be stopped in an axially intermediate position of the rod by engagement of respective radial faces on an abutment member mounted on the rod for axial movement and on a rigid abutment member fixedly mounted on the cylinder and projecting into the normal axial path of the other abutment member which may be deflected manually from its normal path for release of the rod.

Abstract: A disc brake comprising a caliper housing having axially aligned first and second cylinder bores; a first piston slidable within the first bore and bearing against one of the friction pads; and a second piston slidable within the second bore and having an internally threaded tubular opening into which a clearance adjuster is screwed. The threads of the adjuster are power transmission threads with a helix angle of about 15 degrees, and there is end-wise clearance between the threads sufficient to allow the first piston to move between its retracted and brakes-applied positions. At the end of the adjuster is a head having a conical clutch facing that engages a corresponding conical seat in the bottom of the first piston, so as to exert a powerful rotational clutch action. A spring urges the adjuster toward the bottom of the first piston, and causes the adjuster to unscrew and extent itself whenever there is any clearance between the clutch facing and seat.

Abstract: Locking apparatus for a ram type blowout preventer having a housing with a passageway through which a tubular member may pass; rams movable between a non-sealing position in the housing, in which the passageway is open, and a sealing position in which the passageway is sealingly closed; and an operator assembly for moving the rams between the non-sealing and sealing positions. The locking apparatus may comprise: at least one rod connected to the operator assembly reciprocable between first and second terminal positions in response to movement of the rams between their non-sealing and sealing positions, respectively; and locking means engageable with the rod when in its second terminal position to lock the rams in their sealing positions. A method of operating such a ram type blowout preventer is disclosed also.