Abstract: An energy-efficient method of recovering carbon dioxide (CO2) in a liquid state from a high-pressure gas stream is provided. The method includes cooling, condensing, and/or separating CO2 from a high-pressure gas stream and further purifying the resulting liquid CO2 in a purification zone to thereby provide a purified CO2 product. The purified liquid CO2 product may then be pumped to a higher pressure for further utilization and/or sequestration for industrial or environmental purposes.

Abstract: An object of the present invention is to provide a fluid pressure cylinder improved in assembling performance so as to easily fix a partition wall to a cylinder main body. A plurality of pistons 15a and 15b are incorporated in a cylinder main body 11, axially aligned with each other, reciprocable in an axial direction, and respectively provided with piston rods 17a and 17b. A partition wall 14 is attached to the cylinder main body 11 so as to form pressure chambers 21a and 21b. A stopper space is formed by an engagement groove 31 provided to the partition wall 14 and a slit 32 formed so as to extend in a transverse direction of the cylinder main body 11. A stopper 34 is inserted in the stopper space in the transverse direction of the cylinder main body 11 so as to fix the partition wall 14 to the cylinder main body 11.

Abstract: A vehicle has an internal combustion engine, an automatic transmission with an electrohydraulic transmission control unit, a transmission oil pump driven by the engine, and an electronic engine start and stop system. The start and stop systems switches off the internal combustion engine in operating phases, in which the vehicle is temporarily stopped, if predefined operating parameters are present, and starts the internal combustion engine if a restart signal is present. A purely mechanical pressure accumulator device provides stored hydraulic pressure to the electrohydraulic transmission control unit in a time period following the starting of the internal combustion engine, in which time period, the transmission oil pump is still building-up pressure.

Abstract: A valve for use with a turbocharger is disclosed. The valve may have a valve element movable to selectively direct a flow of fluid. They valve may also have a control portion connected to move the valve element, and a cooling portion configured to receive a pressurized cooling medium from the turbocharger.

Abstract: An apparatus comprising a downhole tool having a body defining an outer surface, a plurality of standoffs distributed about the outer surface, and a hydraulic circuit operatively coupled to the standoffs. The hydraulic circuit includes a plurality of hydraulically actuated pistons, each of which is operatively coupled to a respective one of the standoffs to extend and retract the respective standoff. The pistons are hydraulically coupled and sized to extend or retract the respective standoffs at substantially the same rate in response to a hydraulic control signal.

Abstract: The present system provides a mechanism which provides mechanical locking of an apparatus, with fluid pressure-driven unlocking and an actuating force when an intended level of such pressure has been reached. The present system thus mechanically locks an apparatus against premature actuation caused by, for example, shock or vibration, until it is subjected to a level of pressure intended to actuate it. The present system is suitable for incorporation in any apparatus taking advantage of its ability to utilize fluid pressure to remove a mechanical block at an intended level of pressure and impart an actuating force.

Abstract: The invention relates to a clamping device for a rod which moves in an axial translatory or rotating manner. Said clamping device comprises a housing, a clamping sleeve which is axially fixed therein, a tensioning piston which can be displaced in the housing embodied as a cylinder, and a spring device for pre-tensioning the piston in the direction of the clamping sleeve in the locking state. Said spring device includes at least one helical plate spring which, in the event of a fracture, maintains the holding force and the dynamic course of the same. In one embodiment, the at least one helical plate spring is coaxially arranged in relation to the rod. In another embodiment, a plurality of helical plate springs are arranged on the circumference of the rod such that they are parallel with the axis thereof, for distribution of a pre-tensioning force acting on the spring device.

Abstract: A self-locking braking device, for rotary shafts connectable to external loads, comprises braking means which can be operated to lock, respectively to release the rotation of a drive shaft; the braking means consist of a rigid braking disk, rotating with the drive shaft, and slidingly supported in an axial direction between two clutch members, one of which is secured to a support body for the drive shaft, while the other clutch member is supported by a plate which is elastically biased against the braking disk and operatively connected to a pneumatic cylinder for releasing the brake.

Abstract: A fluid pressure cylinder can apply a fastening force to an axially movable reciprocating rod. A reciprocating rod 13 is mounted in a case main body 10 so as to be reciprocable in a forward direction and a backward direction, and two lock units 16a and 16b are incorporated in the case main body 10, and the lock units 16a and 16b include: lock sleeves 18a and 18b mounted axially movably and having taper surfaces 22a and 22b; and retainers 19a and 19b holding steel balls 21a and 21b that are fitted in the reciprocating rod 13 axially movably and engaged with the taper surfaces. A fastening cylinder 41 that contains a fastening rod so as to be reciprocable in a fastening direction and a fastening release direction is attached to the case main body 10, a fastening surface 44 contacting with the lock sleeves 18a and 18b being formed in the fastening rod, and the reciprocating rod 13 is fastened by the two lock units 16a and 16b.

Abstract: The invention relates to a supporting device for supporting substrates in a component placement machine including a housing (1), a piston rod (5) arranged in the housing so as to be movable in its longitudinal direction in the housing (1) by pressurized fluid and having one end extending outside the housing (1) and a locking mechanism (7 to 9) by which displacement of the piston rod (5) in its longitudinal direction can be prevented. The locking mechanism (7 to 9) includes clamp (8) movable by an adjuster (7) in a direction transverse to the longitudinal direction of the piston rod (5) between an active position for blocking the piston rod (5) and an idle position in which the piston rod (5) is movable in its longitudinal direction. The clamp (8) have been arranged in the housing (1) so that in the active position said clamping means (8) directly engage the piston rod (5).

Abstract: The locking device comprises a plurality of rolling wedging members consisting of diablo-shaped rollers with two cylindrical end portions and an intermediate portion which is concave according to a generatrix in the form of an arc of circle whose radius corresponds to the half-diameter of a cylindrical rod of the actuator to which the device is associated. The rollers are adapted to be wedged between the rod and convergent surfaces which are formed in a fixed body of the device. The convergent wedging surfaces are convex surfaces having cross-sections in the shape of an arc of circle whose radius of curvature corresponds to the radius of curvature of the arched longitudinal profile of the concave intermediate portions of each of the rollers, as well as to the half-diameter of the rod. Each of the convex surfaces is in engagement with the concave intermediate portion of one of the rollers.

Abstract: A pneumatic or hydraulic cylinder (10) having a bore (12) cooperating with a piston (18). Extending from the piston (18) is a piston rod (37). There is further provided a pawl (26) which is engageable with the piston (18) to retain the piston (18) at a desired location. The pawl (26) is moved from engagement with the piston (18) upon fluid under pressure being delivered to one end of the cylinder (10).

Abstract: A pressure medium activated piston-cylinder device comprises a cylinder with two end walls both having pressure medium communication ports, a piston movably guided in the cylinder and connected to a piston rod which extends out of the cylinder through a sealed-off passageway in a first one of the end walls, and a piston rod locking device located in the passageway and including a clamping element axially locked to the first end wall, and an activating member which is continuously spring biased toward a clamping element activating position and shiftable by pressure medium toward a release position, against the spring bias force, wherein a manually operable release mechanism comprises a tubular thrust element movable in the first end wall between a rest position and an activating member releasing position, and a maneuver spindle having a cam surface for co-operation with a cam surface on the thrust element for moving the thrust element between its rest position and the activating member releasing position as th

Abstract: A fluid circuit for raising and lowering an implement including a quick drop valve member movable between at least a first position and a second position, the first position corresponding to a non-quick drop hydraulic fluid flow path of the fluid circuit and the second position corresponding to a quick drop hydraulic fluid flow path of the fluid circuit, the quick drop valve member being movable between at least the first and second positions based on pressures in the fluid circuit produced by hydraulic fluid. The fluid circuit further including a control system configured to selectively apply a biasing force against the quick drop valve member biasing the quick drop valve in the first position, the control system providing the biasing force independent of pressures in the fluid circuit produced by the hydraulic fluid.

Abstract: The locking device comprises a plurality of rolling wedging members consisting of diablo-shaped rollers with two cylindrical end portions and an intermediate portion which is concave according to a generatrix in the form of an arc of circle whose radius corresponds to the half-diameter of a cylindrical rod of the actuator to which the device is associated. The rollers are adapted to be wedged between the rod and convergent surfaces which are formed in a fixed body of the device. The convergent wedging surfaces are convex surfaces having cross-sections in the shape of an arc of circle whose radius of curvature corresponds to the radius of curvature of the arched longitudinal profile of the concave intermediate portions of each of the rollers, as well as to the half-diameter of the rod. Each of the convex surfaces is in engagement with the concave intermediate portion of one of the rollers.

Abstract: A pneumatic or hydraulic cylinder (10) having a bore (12) cooperating with a piston (18). Extending from the piston (18) is a piston rod (37). There is further provided a pawl (26) which is engageable with the piston (18) to retain the piston (18) at a desired location. The pawl (26) is moved from engagement with the piston (18) upon fluid under pressure being delivered to one end of the cylinder (10).

Abstract: In a brake (53) for a hydraulic motor (10), a braking piston (66) is added that can move toward and away from fixed friction discs (54) and rotating friction discs (55). A braking passage (73) leads a high-pressure fluid into the braking piston (66) to press the braking piston (66) to the friction discs (54, 55).

Abstract: A pivot-chuck actuator has a housing extending along an axis and formed centered on the axis with a piston chamber and a vane chamber offset and separate from the piston chamber. A piston axially displaceable in the piston chamber is axially fixed to a shaft extending from the housing on the axis. A vane element on the shaft angularly subdivides the vane chamber into a pair of angularly offset compartments and formations rotationally couple the vane element to the shaft for joint rotation therewith while permitting relatively axial movement of the vane element and shaft. The compartments cam be alternately pressurized to rotate the vane element and shaft about the axis. A pair of counterweights angularly fixed on the shaft axially flank the vane element. Formations rotationally couple the counterweights to the shaft for joint rotation therewith while permitting relative axial movement of the counterweights and shaft.

Abstract: An automotive suspension-locking device mounted to a shock absorber having a cylinder and a piston rod, the suspension-locking device includes a brake band provided around the piston rod of the shock absorber for locking and unlocking the shock absorber, structure for controlling the brake band, the control structure being connected to both end portions of the brake band, and an actuator connected to the control structure by a piston rod thereof for actuating the control structure.

Abstract: The locking device comprises resilient repulsion means (58) which react between a fixed body (16) and one or more rolling members (42) and which tend to urge these members in the direction of wedging between two wedging surfaces (34, 36) associated with the body (16) and with the rod (12) of the actuator (10), respectively. A control piston (48) is arranged so as to engage the rolling members (42) in order to urge them in the release direction under the effect of a thrust exerted on the piston in the opposite direction to the force exerted by the resilient means (54).

Abstract: This fluid pressure cylinder with a lock mechanism is adapted to provide, on the lock mechanism cover, an area where valves for controlling the cylinder and lock mechanism can be installed. In the cylinder, a brake shoe grips a piston rod 6 via balls held by a retainer inside a lock mechanism cover 21 using a tapered ring which is driven by a brake spring and returned to its original position by a release piston. A cylinder port 8 that supplies or discharges compressed air to drive the piston is provided on the side of a cylinder 1 inside the lock mechanism cover 21. On the opposite side an unlocking port 34 which leads to a pressure chamber driving a release piston is disposed and a manual opening actuator 45 is provided. This arrangement is intended to ensure a flat area 48 where valves can be installed to control compressed air fed through the ports.

Abstract: A brake for linear movement devices comprising a device. The brake means includes a bar which extends parallel with the path of movement of the device and which accommodates a pressurizable hose-like element that extends along the bar. The invention is characterized by a slat spring accommodated in the bar and extending on one side of the hose-like element, a brake disposed along the slat spring and movable transversely to the longitudinal direction of the hose-like element and the spring and located adjacent one longitudinally extending edge of the spring, for movement transversely to the longitudinal direction and essentially in the plane of the spring when the hose-like element is placed under pressure and the spring is flexed outwardly. The brake also includes a slide shoe which is guided in the rail and connected to the device and actuable by the brake device that is movable towards the slide shoe.

Abstract: A rod clamp device having a rod clamp sleeve with a frusto-conical outer surface and an annular cam with a frusto-conical inner surface and an annular ball guide cage arranged to equalize movement of the bearing balls in circumferentially spaced paths along the clamp sleeve so that the annular cam applies pressure through the bearing balls uniformly around the rod clamp sleeve when the cam is moved axially in one direction to a rod clamp position, and the annular cam uniformly releases pressure on the bearing balls when the cam is moved axially in an opposite direction to a release position. The rod clamp sleeve has slots and the ball guide cage is keyed to the clamp sleeve to maintain a preset angular relation therebetween while allowing relative axial movement.

Abstract: A securement assembly for reliably locking a vehicle component such as a wheel or a body panel to a vehicle. The securement assembly includes a slotted sleeve that is engageable with an opening of the vehicle component, to lock the component in place. The slotted sleeve incorporates a number of deflectable fingers, and a mandrel can be reciprocated along the sleeve's central longitudinal axis, between an extended position and a retracted position. When the mandrel is in its extended position, the sleeve's deflectable fingers are moved to a position that allows the vehicle component to be removed and replaced, whereas when the mandrel is in its retracted position, the fingers are moved into engagement with the vehicle component, to positively lock the component in place. A compression device, e.g.

Abstract: A method and apparatus for operating a fluid actuated actuator between one and another alternate positions provides different forces for locking and unlocking the actuator. The actuator may use the same fluid pressure to operate a primary piston within a cylinder and to operate the locking mechanism. Actuator fluid is communicated to unlock the lock member and to move the piston back to its open or unactuated position. A sequencing valve determines the proper sequence of actuating the primary piston before the locking mechanism is driven in place, and clearing the locking mechanism prior to reciprocating the piston back to its unactuated position. Different forces for locking and unlocking the locking mechanism is provided by a free-floating piston mounted on a guide rod. The invention may also be applied to a BOP or the like where different opening and closing forces are desired.

Abstract: A safety, fluid-actuated cylinder-and-piston mechanism for use with an article which is movable between first and second positions. The mechanism comprises a conventional, fluid-actuated cylinder-and-piston mechanism and an automatic locking bar. The piston rod of the cylinder-and-piston mechanism has one end attached to the movable article, and is movable between a fully retracted position in which the article is in its first position and a fully extended position in which the article is in its second position. The locking bar has a pivot end proximate the attachment between the piston rod and the movable article, and an opposite, nonpivot end. The locking bar is pivotable between a lowered and fully raised position and has a plurality of partially raised positions between its lowered and fully raised positions.

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: A fluid pressure operated braking device for a piston rod. The braking device includes a clamp sleeve and a cam member spring biased axially in a direction to actuate the clamp sleeve to a clamp condition, and a fluid pressure operator that provides a hydraulically amplified force for moving the cam member in opposition to the spring to release the clamp sleeve. The fluid pressure operator includes a first piston operated in response to fluid pressure applied thereto to produce a force correlative with fluid pressure and the first piston is connected to a second piston that pressurizes a non-compressible fluid in a closed pressure chamber communicating with a third piston, and a third piston actuates the cam ring in opposition to the spring to release the clamp ring.

Abstract: A pneumatic piston-cylinder unit has a cylinder (1) in which an air piston (4) with a tubular piston rod (5) is reciprocably actuated by compressed air from two main air channels (18, 19). The air cylinder (1) includes an integrated hydraulic control system (6) having an actuation device (8) which is fixedly mounted in the air cylinder (1) for creating a flow of hydraulic fluid through hydraulic control system (6) when compressed air is present in the main air channels (18, 19) and for stopping the flow of hydraulic fluid and thereby preventing the air piston from moving when there is no compressed air in the main channels (18, 19). A piston (34) and a cylinder (28) of the hydraulic control system (6) are displaceable an adjustably long distance in relation to each other to make it possible to open and close, respectively, a larger or smaller hydraulic fluid passageway thereby controlling the moving speed of the air piston (4) while maintaining the air pressure.

Abstract: A motor or pump includes a stator and a rotor supported for rotation with respect to the stator by a bearing arrangement. The rotor has a cylinder block thereon having radial cylinder bores equipped with radially reciprocable pistons. Rollers on the pistons abut a cam ring fixed to the stator so that the pistons to reciprocate radially to displace fluid when the rotor turns relative to the stator. The stator includes a control device fixed thereon having a pair of fluid passages therein. One side of the control device constitutes a distribution face with outlets therein connecting the fluid passages to the cylinder bores as the rotor rotates. A counterpart fastens to the rotor adjacent the opposite side of the control device so as to define an annular chamber therebetween. A shuttle valve operatively interposed between the passages and chamber ensures that the chamber remains in connection with the passage having the higher pressure.

Abstract: A method is provided for locking jet engine exhaust nozzle position in a hydraulic system having nozzle actuators connected by a synchronization cable. The synchronization cable engages with a conical brake locking mechanism to prevent cable rotation in the event of a hydraulic failure. The nozzle is locked in position at the time of the hydraulic failure. This prevents a significant decrease in usable thrust.

Abstract: A forward-moving inching unit and a backward-moving inching unit are built in a casing (1) which is slidable relative to a guide member (b).

Abstract: A hydraulically controlled ram actuating mechanism 10 for a blowout preventer controls the opening and closing of a ram block 12 interconnected with a ram 14 movable within a ram housing 26 along ram axis 16. The ram piston 24 and a locking piston 62 are each movable within the ram housing in response to fluid pressure. The locking piston includes a plurality of substantially planar tapered locking piston surfaces 72 circumferentially arranged on the exterior of the locking piston and inclined at an acute positive cam angle. A plurality of locking rods 40 are each secured to the ram housing 26 and are circumferentially spaced about the locking piston, with each locking rod including a substantially planar tapered locking rod surface 82 thereon inclined at an acute negative cam angle.

Abstract: A device for clamping an axially movable rod comprising a housing having a cylindrical inner wall and end walls that slidably support the rod. A pair of annular rod clamp rings in the housing having inner clamping surfaces for engaging the rod and frusto-conical outer surfaces, and a pair of annular pistons in the cylinder having an inner surface engaging the outer surface on the annular rod clamp rings and an outer surface slidable in the cylindrical inner wall of the housing. The pistons have spring receiving cavities radially intermediate the inner and outer surfaces thereof and the springs disposed in the cavities for moving the pistons axially in a direction to clamp the rod. A fluid pressure chamber is provided in the cylinder for actuating the pistons in a direction to release the rod.

Abstract: An improved welding apparatus and method of use including a pair of opposed electrodes mounted on arms which are fixed against outward displacement during the application of the welding current. One of the arms includes a pneumatic cylinder for moving an electrode to and away from the work piece. The cylinder includes a piston rod attached to a clutch by a ball screw mechanism. A brake assembly is connected to the unidirectional clutch to prevent outward displacement of the electrodes during expansion of a weld nugget and permitting inward movement of the electrodes to provide indentation of the weld after the nugget softens.

Abstract: A pressure-discharged type retaining system is designed so that supplying and discharging of a high-pressure fluid permits the relative movement of an annular outer member and an inner member inserted and fitted therein in either or both of axial and circumferential directions and retains the outer and inner members stationary. In the prior art, to insure the smoothness and safety of the operation, a high processing accuracy, a measuring accuracy and the like have been required in the production of such a system, resulting in an increased cost. According to the present invention, either one of the adjacent inner and outer members is formed, on its outer or inner surface, with a metal layer which has a predetermined difference in hardness from that of the other member, thereby solving the above subject.

Abstract: An actuator lock is provided to prevent movement of an actuator until the actuator lock is released. A first member of the lock is movable in response to fluid pressure within a chamber to move from a locked position to an unlocked position allowing the actuator to move. The first member is held at the unlock position by a latching member so that the lock cannot return to the locked position. During testing of the actuator, a test member is operable to reversibly move the first member from the locked position to an unlocked and unlatched position.

Abstract: A linear drive is disclosed comprising a single-acting pneumatic piston cylinder unit, at least one spring which acts against the pneumatic force and loads the piston rod in the direction of one end position, and one form-locking pneumatic locking mechanism respectively for each of the two end positions of the piston rod.

Abstract: A method for locking a hydraulic actuator in a predetermined position and a locking hydraulic actuator are provided. The method includes the steps of supplying hydraulic fluid to a forward chamber in the hydraulic actuator, transferring the hydraulic fluid from the forward chamber into a forward moiety of the rearward chamber in the hydraulic actuator, and sealing the hydraulic fluid in the forward moiety of the rearward chamber to accomplish the locking function. Conversely, the actuator lock is released by the application of fluid supply pressure to the rearward variable chamber.

Abstract: A piston-cylinder unit for pressure fluids includes a housing bounded by a head piece at each end thereof; a cylinder disposed within the housing; a piston reciprocatingly movable within the cylinder; a pulley having a circumferential outer surface is mounted for rotation about an axis within each of the head pieces; a pull belt is secured to the piston and looped around the outer surface of the pulleys; a power pick-up is attached to the pull belt; a braking device for the pull belt is disposed within the head piece and juxtaposed with at least one of the pulleys and has a shape which is complementary to at least a portion of the circumferential surface of the pulley; and a feed conduit connected to the head piece for feeding the pressure fluid to the braking device.

Abstract: A pressure intensifier drive unit has walls that form a cylinder with an intermediate divider plug separating a working chamber and a pressure intensifying chamber aligned in the cylinder. The working chamber has a working piston and a working piston rod extending from an end of the cylinder. A carrier piston is located between the working piston and the divider plug and has a cylindrical recess receiving the working piston, a hydraulic fluid chamber, and a bore. A locking piston is movably mounted on the carrier piston and locks the carrier piston in place when the working piston rod initially contacts a workpiece. A pressure intensifier piston in the pressure intensifying chamber has a pressure intensifier piston rod extending through a bore in the divider plug and through the bore in the carrier piston into the hydraulic fluid chamber.

Abstract: A power cylinder of the type in which the piston may be locked to maintain am associated tool or clamp in a fixed position. A nut is provided in an end wall of the cylinder and the piston rod of the piston passes through the nut. The initial portion of the forward stroke of the piston is accomplished by the introduction of fluid pressure into the cylinder and, as the piston approaches the final portion of its stroke, the threaded portion of the piston rod engages the nut whereupon the nut is rotated to threadably advance the piston through the final portion of its stroke. The rotation of the nut is accomplished by pressurized fluid acting against a piston rack which rotates a gear which in turn rotates the nut. The center line of the piston rod is offset from the center line of the piston to preclude rotation of the piston and of the piston rod.

Abstract: The braking device (2) is formed between a force collector (3) and a cylinder casing (1) by way of slider tracks (5) and counter slider tracks (6) and by sliding bodies (7) guiding the slider tracks and counter slider tracks in a working cylinder without piston rod. The adjusting elements (12) for the setting of a sliding or a braking play can be set according to the sliding bodies (7). In order to achieve a compact construction, a low construction height, as well as a lowest possible number of parts, the braking device (2) is disposed symmetrically to a slider plane and a casing center longitudinal plane (19), respectively. The braking device is furnished with a force member (20) acting in the region (21). The lever element (22) engages centrally in each case with the lever arms (22a, 22b) on the adjusting element (12). A press-on force generating the braking force centrally engages the lever elements (22).

Abstract: A lock cylinder for a backhoe slide frame which provides for a positive lock of the slide frame in selected positions is described. The slide frame is supported on two generally horizontal rails that are vertically spaced, and the lock cylinders mount between the vertically spaced rails. The lock cylinders each have a piston that acts to hold the slide frame seated against the upper one of the rails. The piston also provides a wedging action on at least one rail to hold the slide frame from fore and aft movement relative to the rail.

Abstract: A hydraulic lock cylinder in which a cross bore is provided in an end structure of the cylinder housing which intersects the hydraulic fluid inlet passage to the central bore of the cylinder; a control piston is reciprocally mounted in the control bore; and pressurized fluid is admitted to the opposite ends of the control bore to shuttle the control piston within the control bore between a closed position in which the inlet passage is blocked and an open position in which the passage is open. The control piston includes a flat surface and a control port opening in the flat surface and an annular fitting screws into the inlet passage housing and includes a seal on its lower end for sealing coaction with the flat surface on the control piston to seal the inlet passsage.

Abstract: A piston sealing arrangement for pressure-fluid-operated systems is disposed in an annular recess of a piston (5) or an associated housing (4) and is composed of a sealing ring element (1A, 1B) as well as an elastic element (2, 3) acting on one side in opposition to the direction of the pressure force (A). Herein the elastic element is dimensioned such that the sealing ring element (1) moves against its elastic element (2, 3) at a pressure smaller than the force against which the piston (6) is moving and by which it is kept on its stop, a pressure-fluid film being formed as a result which safeguards a uniform initial movement of the piston to a largest possible degree.

Abstract: A quick-change arrangement for an excavator is provided for the exchange of tools which are detachably fastened by way of locking elements to an adapter of a bending arm and held on the bending arm so that the tool can be swivelled around a horizontal axis. The locking elements comprise a piston, which is coaxially arranged in a housing and has end-side locking pins which, by way of an interposed pressure spring, can be adjusted into a moved-out operative position and, by way of a pressure admission controlled by the control unit, can be adjusted into a moved-in inoperative position inside the adapter. By this construction of the device, it is achieved that the locking pins are subjected to the tension of the pressure spring in the operative position.

Abstract: A hydraulic cylinder that locks into position has a housing (1) with at least one pressure connection (7) and a piston (3) and rod (6) that travel tight in an out of the housing. The locking mechanism comprises a piston (11) that rests against a spring (35) and a barrier mechanism (23) with a cage of balls (25) that roll radially into a locking position in a locking groove (26) and back into an unlocking position in an unlocking groove (22). The primary piston communicates with a hollow space (18) and acts on a primary participating surface (19) and the locking piston communicates with an unlocking space (13) and acts on an unlocking surface (14) by way of the pressure connection. There is a variable choke (17), which disengages after a while, beween the pressure connection and the primary space (18) in the primary piston (3).

Abstract: A main tail lock for a hydraulic tail trailer comprising a pair of spaced-apart locks which are pivotally secured to the frame of the tail and which are pivoted between locked and unlocked positions by a lock cylinder. When the locks are in their unlocked position, the tail cylinders for the tail may raise or lower the tail of the trailer. When the locks are in their locked position, the tail cylinders are prevented from retracting thereby preventing the lowering of the tail with respect to the main frame of the trailer.

Abstract: A power cylinder assembly including means to positively lock the piston rod of the assembly in the forward extended position of the cylinder assembly. The locking means includes a pair of cam plates that are moved radially outwardly into locking engagement with lock slots defined by inserts positioned in the wall of the cylinder with the radially outward movement of the locking plates being generated by a lost motion connection between the piston and the piston rod in the form of a pin and slot connection. The pin is carried by the piston rod and coacts with cam slots in the cam plates to move the cam plates radially outwardly at the end of the forward stroking movement of the piston assembly so that the final forward movement of the piston generates the radially outward movement of the lock plates.