Abstract: In a hydraulically blockable gas spring a hydraulic chamber and a gas chamber are provided one behind the other within a cylinder. The chambers are separated from each other by a separating wall. A first section of a piston rod is sealingly guided through one end of the hydraulic fluid chamber and is connected with a separating piston within the hydraulic fluid chamber. The separating piston divides the hydraulic fluid chambers into two hydraulic fluid compartments. The fluid compartments are interconnected by a hydraulic flow path. The hydraulic flow path can be selectively opened and closed by a valve. A second piston rod section extends from the separating piston through the separating wall and sealingly enters into the gas chamber. The pressurized gas within the gas chamber provides a biasing action onto the second piston rod section. The hydraulic chamber is completely filled with a hydraulic fluid.

Abstract: The invention relates to a control device for a gas spring which can be locked as desired by displacement of a sliding control finger. Two axially elongated, diametrically opposed windows (14), at least one of which is larger at the end nearest to the gas spring, pass through a tubular connector (1) coaxial with the control finger (6). A lever (2) which has thinner parts (25, 26) flanking a wide part (24) engages in these windows. Devices (7) are provided so that, after mounting on the gas spring, the wide part (24) is unable to reach the wide section of the window, thus preventing the lever from being dislodged. The edges of the windows (14) form bearing points for the pivoting movement of the leaver and the actuation of the control finger (6).

Abstract: A gas spring is provided in an illustrational example between a framework and a trunk cover of a motor vehicle for compensating for the weight of the trunk cover during movement of said trunk cover. The gas spring is hinged to the framework and to the trunk cover. For eliminating the spring force action on the hinge between the trunk cover and the gas spring in the closed position of the trunk cover, the part of the gas spring hinged to the trunk cover is supported on the framework, when the trunk cover is in its closed position. Alternately, the gas spring is locked when the trunk cover is in its closed position.

Abstract: A hydraulic damper has an oil lock mechanism for preventing bottoming when the hydraulic damper is fully compressed. The hydraulic damper also includes an outer tube, an inner tube, a cylinder movable with the inner tube, a piston rod movable with the outer tube, a piston fixed to a distal end of the piston rod, and a coil spring disposed in the inner tube. The oil lock mechanism comprises an oil lock piece mounted on an upper end of the cylinder, and an oil lock tube disposed concentrically between the cylinder and the inner tube and having a larger-diameter portion which can be spaced from the oil lock piece when the hydraulic damper is extended and a smaller-diameter portion which can be held in sliding contact with the oil lock piece when the hydraulic damper is compressed.

Abstract: A longitudinally controllable adjustment device, in particular a gas spring partially filled with a fluid has a piston disposed on a piston rod. In order to achieve simple manufacture and assembly and high operational safety, a valve housing for receiving a valve is provided on the piston rod. Further, the piston axially covers to total valve. The piston is secured to the piston rod by deformation, which simultaneously results in a pre-stressing of a seal sealing in four directions. The piston rod with the valve is compressed against a seal in the piston, which seal sealingly abuts on an annular bottom of a receptacle, on the receptacle, on the valve and on the valve body.

Abstract: The invention consists of a novel tilt damper equipped with two oil chambers; one in the piston-rod extended position and the other in the piston-rod retracted position, which are respectively connected to a gas chamber through an oil passage where a relief valve and a check valve are provided. These valves are alternatively disengaged from the closed condition by an external operator. When these valves are open, oil flows freely into and out of them to allow gas pressure to drive the piston rod in the direction of extension. When only the check valve on the piston-rod oil chamber in the extended position is open, the tilt damper does not move in the direction of retraction. When overload is applied in the direction of extension of the piston rod, the tilt damper extends by applying a negative pressure to the oil chamber on the retraction part. When the overload is removed, the tilt damper automatically returns to the original position.

Abstract: A door closer is set forth having a housing, a plunger rod in the housing with a plunger at the inner end of the rod, and a main spring around the rod between the plunger and a housing end for urging the rod into the housing. An actuator carried at the housing end with an opening for the rod and mounted for transverse sliding motion relative to the rod, with a spring for urging the actuator into a latch space in the rod is utilized. With the door closer connected to a door, the actuator slides into the latch space when the door has been opened, to hold the door open. A further opening movement raises the actuator out of the latch space and a sleeve maintains the actuator raised, permitting closing of the door.

Abstract: A composite hydraulic cylinder apparatus which has a pneumatic cylinder mechanism, a braking oil hydraulic cylinder mechanism associated concentrically with the pneumatic cylinder mechanism, an oil passage for communicating between the front chamber and the rear chamber of the oil hydraulic cylinder mechanism, and a control valve provided in the oil passage for controlling the flow of the oil. Thus, the apparatus provides high positioning accuracy, a large holding force, economy and small size as a movable element control system, and can be applied as a buffer for the movable element.

Abstract: In a firing weapon with an elevatable weapon barrel, it must be possible to fix or lock the weapon barrel in each desired position. For this purpose, known firing weapons are equipped with braking devices in which large frictional forces occur, thereby making it necessary to use servo-mechanisms. In accordance with the invention, the elevation of the weapon barrel is fixed or locked by means of a cylinder and a piston. The piston comprises a closeable through-passage opening through which a pressure medium flows, as long as the through-passage opening is open between a chamber located on one side or face of the piston into an other chamber located on the other side or face of the piston. The through-passage opening is closeable for fixing or locking the weapon barrel at a predeterminate elevation.

Abstract: Apparatus applicable to the piston rod of a control cylinder inherently operable to selectively limit and control the extent of its retraction. A preferred illustrative embodiment, as applied in use, conforms to a generally L-shaped structure the long leg of which is slim, substantially uniform in width, at least in part transversely arcuate along the length of its inner operative surface, highly resistant to compression and has its base end pivotally connected to the short leg of said structure. Springs interposed between these legs in the pivotal interconnection thereof are established in a secure and stable relation thereto in a manner to positively apply in continuing bias on the long leg which induces it to incline to and over the length of the short leg to inherently form therewith an acute angle. These legs are so formed to lend the minimal amount of material of which they are comprised a very high degree of load bearing strength for their size.

Abstract: A clamping device for use with a gas spring in the form of a cylinder containing a gas, and a piston and piston rod movable within the cylinder. The clamping device is secured to the end of the cylinder through which the piston rod passes, and includes a clamping portion that engages and clamps around the piston rod to provide resistance to movement of the piston rod relative to the cylinder. The clamping device is a U-shaped structure having clamping legs that can be moved toward each other by a bolt and nut arrangement. The clamping device can be made from an injection molded plastic material, and the device permits continued use of the gas spring after the gas pressure has diminished to a level at which replacement of the spring would otherwise be required.

Abstract: A static hydraulic continuously variable transmission includes a cylinder block which is secured to an output shaft and comprises a pump cylinder of a hydraulic pump and a motor cylinder of a hydraulic motor, these cylinders being connected to each other, wherein, a number of pump cylinder bores and a number of motor cylinder bores are annularly arranged respectively in the pump cylinder and the motor cylinder and the transferring of a working oil between the group of the pump cylinder bores and the group of the motor cylinder bores is conducted through the medium of a pair of oil chambers which are concentrically provided around the output shaft communincation between these cylinder bores is controlled by a number of first and second dispensing valves extending between both the oil chambers and adapted to be reciprocally radially moved.

Abstract: A fluted piston for a volume-compensated pressurized adjustable length positioner. The cylinder is charged through the charging/discharging valve so that the opposed fluid chambers defined inside the cylinder bore by the slidably movable piston are filled with compressible fluid at elevated pressure. An actuating rod in the piston operates a valve in the piston to open communication between the opposed chambers and allow selective extension and retraction of the piston rod. The large-diameter piston rod has an elongated head configuration formed by flute ribs. These ribs provide bearing support for the extended piston rod and create a volume compensating space in the piston head to account for the large ratio of extended-rod cylinder volume to retracted rod cylinder volume.

Abstract: The invention discloses a lifting telescoping tube which comprises a first tube receiving a pressure liquid, a second tube filled with a pressure gas, a first piston affixed to one open end of the second tube having a first through-passage and a second through-passage intercommunicating the first and second tubes, a check valve disposed in the second through-passage for preventing the pressure liquid from flowing into the first tube from the second tube, a second piston provided in the second tube dividing the second tube into a variable-volume liquid chamber and a variable-volume gas chamber.

Abstract: A fluid-pressure elevator comprising an elevator frame for supporting a cage; a fluid pressure cylinder attached to the elevator frame and adapted to vertically move the cage by controlling the rate of charge or discharge of pressure fluid; a rope means for connecting the cage and the plunger of the fluid pressure cylinder to each other while being supported by pulleys attached to upper portions of the elevator frame.

Abstract: The adjusting mechanism is used for exerting a force on two components moveable relative to one another and comprises a cylinder, a piston and a piston rod. A guide rod is also provided on the piston and is guided in a guide connection of a bottom cylinder casting. A control piston is displaceably guided in a longitudinal bore of the piston and in a further longitudinal bore of the guide rod. The piston contains transfer ducts, which are either obturated by the control piston or are freed or exposed by a smaller diameter portion of the control piston. An inner cylinder chamber is completely filled with a flowable or fluid grease. As a result, the piston rod can be locked in position by the control piston closing the transfer ducts and, on releasing or opening the latter, the piston rod can be moved. The locking of the adjusting mechanism in a specific position, as is particularly required in the case of tiltable chairs, is consequently facilitated in comparison to known adjusting mechanisms.

Abstract: A flexible tool bar apparatus including a first tool bar adapted to have earth working implements attached thereto and a second tool bar also adapted to have earth working implements attached thereto. Two tool bars are pivotally attached at the inner ends thereof. A hydraulic cylinder mechanism is operatively attached at one end thereof to the first tool bar and is operatively attached at the other end thereof to the second tool bar. A fluid device is provided for selectively supplying fluid under pressure to a hydraulic cylinder mechanism for causing the hydraulic cylinder mechanism to hold the tool bar from flexing. The tool bar can flex when the fluid pressure is released.

Abstract: A gas cylinder for applications requiring height adjustments such as found in chairs, stools, or like structures supported by columns. The cylinder has an elongated rechargeable unit of double-wall construction provided with a springless check valve inside a fluid port thereof preferably all of molded plastic. A single-piece sealed plunger assembly includes a single actuating rod with velocity controls incorporated therein which permit vertical extension from collapsed to fully-extended positions. Depression of the actuating rod allows circulation of the pressurized fluid between the chambers, with pressure force acting to extend the plunger when the unit is unloaded. When the unit is loaded, the plunger can be retracted.

Abstract: An add-on mechanical support assembly is used for supporting failed gas struts or as a safety device in combination with operational gas struts. The support assembly includes a generally tubular support having a slot extending lengthwise. The tubular support has different lengths on different sides. An upper end on a shorter side is used for engaging part of the cylinder of a gas strut in order to block the gas strut from retraction. An upper end of the longer side provides a thumb tab area such that one may push the support out of its blocking position without placing ones hand or fingers in a position where one might be pinched by the retraction of the piston rod of the gas strut to within the gas cylinder. A slotted tab extends downwardly from the bottom of the support and allows a screw to attach a locking block or collar with split ends to the piston rod of the gas strut. Breakaway sections are used on the support to allow adjustment for different lengths.

Abstract: The adjusting device possesses a hydraulic cylinder in whose cylinder tube there are housed a main piston equipped with a piston rod, an auxiliary piston and a force-exerting spring. The cylinder tube is closed off at both of its ends by an associated end flange. The outer surface of the cylinder tube simultaneously constitutes the guide surface of a guide tube which is fixedly connected by means of a connecting flange with the piston rod. Since the cylinder tube possesses an essentially constant or uniform inner diameter and outer diameter, the guide tube can be constructed to be so long that the adjusting device is stable enough to serve as a supporting column or pillar, e.g. for a chair or other seat structure.

Abstract: A gas spring for supporting a cab enclosure pivotably mounted to the body of a skid-steer vehicle. A stop tube is mounted to a piston rod and is telescopically cooperable with a cylinder body. Two parallel slots extend in a transverse direction through the stop tube. A stop slide has a pair of legs which are adapted to slide within the slots of a stop tube. A release portion of the stop slide is sized to permit the cylinder body to pass between the legs, while a stop portion is sized to prevent the cylinder body from passing between the legs. A spring urges the stop slide toward a stop position at which the stop portion of the stop slide is aligned with the cylinder body when the piston rod is extended. The cab enclosure is thereby latched to a tilt-back position.

Abstract: A pneumatic spring having a cylinder piston and piston rod biased toward extended condition by compressed gas in the cylinder, an elongated cover tube severed at one of its ends to the outer end of the rod, extending over the length of the rod to define an annular space therebetween, and always in axial alignment with and extending over portions of the cylinder. A transversely shiftable plunger lock assembly on the cover tube near its open end includes a fixed body and a lock plunger movable transversely of the piston axis into the annular space when the rod and cylinder are extended, to abut the annular end of the cylinder to securely retain the assembly in one position, preferably a substantially extended condition.

Abstract: Lockable piston-cylinder assembly to be mounted between two parts being movable relative to each other such as a frame and top or foot end of a bed structure. The two chambers resulting from the division of the cylinder in a piston are interconnected by a hollow piston rod provided with openings. At least one of these openings can be closed by valve member arranged in said piston rod and so fluid communication between these chambers is controlled. Valve member is actuatable from one end of the piston rod outside cylinder. For obviating undesired pressure build up in space or for controlling the pressure in this space a connection is provided to the exterior of cylinder.

Abstract: In a hydraulic positioning device a piston divides the cavity within a cylinder into two working chambers. The piston is connected with a piston rod passing through one end of the device and with a volume compensating rod through the other end of the device. The piston rod is provided with a passage which can be opened and closed by a valve so as to allow optional adjustment and blocking of the piston rod. The hydraulic liquid within the working chambers is subjected to volume variation in response to varying temperatures. With the aim of compensating such volume variations a partition at one end of the cylinder is supported by an abutment of the cylinder through an axially deformable compensating body having preferably a deformation force--deformation path characteristic which is responsive to temperature.

Abstract: A hydropneumatic spring usable as steplessly blockable setting device comprises a by-pass connection in its piston. In this by-pass connection there is arranged a shut-off valve actuatable from the exterior. Furthermore the by-pass connection can be opened by excess pressure in each of the two working chambers. In this way the setting of length of the hydropneumatic spring can be altered by predetermined inward and/or outward thrust forces even when the shut-off valve is closed.

Abstract: In the illustrative embodiment of the invention as described an engine bonnet is articulated to the framework of a motor car. A gas spring is articulated to both the framework and the bonnet. The gas spring balances part of the weight of the bonnet when the bonnet is to be opened by hand. In case of an accident the framework and/or the bonnet may be crushed in longitudinal direction of the car. In such case the piston rod of the gas spring is pushed inward of the cylinder beyond the normal innermost operational position and a retaining device becomes effective so as to prevent the piston rod from returning towards its outermost operational position.

Abstract: An adjustable-length gas spring has a compressed gas-filled housing in which a piston with a piston rod is sealingly guided. At one end of the housing is provided a valve with a valve pin for connecting or separating two housing chambers, the valve pin being movable into the housing against the force exerted thereon by the gas pressure with the valve in the open position. The pin is movable against such force when the valve is in the closed position. There is also a permanent release mechanism for securing the valve pin when the valve is in the open position. In order to permit a particularly simple operation of the gas spring, the permanent release mechanism is formed by a bi-stable locking mechanism constructed in the manner of a mechanical flip-flop and which is coupled to the valve pin, being operated by the insertion thereof into the housing.

Abstract: In a fluid-operated device such as a gas spring a piston rod is axially movably guided through a passage in an end wall of the gas spring. A sealing disc of elastomeric material is axially compressed between two supporting faces and engages the piston rod with a convex radially inner edge. The apex of the edge is substantially midway of the axial thickness of the sealing disc. Preferably the sealing disc has also a radially outwardly convex sealing edge which is in sealing engagement with a stationary face surrounding the sealing disc.

Abstract: A switching valve device provided in an oil passage in which the flow of oil pressure is supposed to occur in both directions, the switching valve device having two check valves provided in the oil passage so as to allow a flow of oil pressure in respective directions opposite to each other, the check valves being biased by means of springs in their respective closing direction, and means is provided for forcibly open the check valves against the bias of the springs. Thereby the switching valve device selectively assumes a first state which allows a flow of oil pressure in one direction, a second state which allows the flow in the other direction, and a third state which does not allow such flow in any direction.

Abstract: An apparatus for setting and maintaining a predetermined projected relation of a piston rod of a gas strut or like device with reference to the cylinder unit of which it forms a part having particular application to the support of a hatchback or rear deck closure panel, trunk lid or hood of an automotive vehicle in its open condition comprises a generally L-shaped structure formed to be firm and resistant to deformation save for the longer leg thereof and a limited portion of its shorter leg being provided with a limited capability of lateral flexing. The longer leg of this structure is normally inclined inwardly to and slightly over the shorter leg thereof.

Abstract: A tie-down clip is described which is adapted for retaining the rod of a pressurized suspension unit in a retracted position within the suspension unit cylinder thereby protecting the rod from damage during shipping and handling and also reduces the size of the necessary packaging for the suspension unit. The tie-down clip has a hook-shaped end which engages the cylinder of the suspension unit and a top plate which receives the piston rod and engages a stop formed by the rod to retain the rod from extension. Two embodiments are described having differing shapes of apertures in the tie-down clip top plate.

Abstract: In a steplessly adjustable hydropneumatic device the spring chamber of which is arranged at the piston rod exit end and which works with a liquid locking, a very simple hydraulic locking is obtained even for high traction stressing upon the piston rod in that both an annular separator piston and the partition are arranged in the inner chamber of the container, which is penetrated by the piston rod. For the hydraulic traction locking in the case of traction forces exerted suddenly upon the piston rod a valve device is provided which cooperates with the piston rod.

Abstract: A re-chargeable self-contained servo cylinder for the control of force with variable piston positions under load includes an elongated cylinder housing having a tubular body with open receiver end and closed opposite end by a cap which includes a central port provided with integral directional check valve for supply of working fluid under pressure during cylinder charging, a piston and rod assembly slidably received inside the cylinder including a rod end closure with seals slipped over piston rod and secured inside the open receiver end so as to protrude an end portion of the piston rod for attaching to a load carrying platform, an integral flow control valve with control rod inside an elongated central bore of the piston rod for control of working fluid communication between the sides of the piston via a fluid opening provided therein when cylinder becomes pressurized by the working fluid and for maintaining a given piston position inside cylinder fixed when the flow control valve is closed thereby also fix

Abstract: Gas springs are frequently used for assisting the movement of a movable construction unit, e.g. a boot lid with respect to a stationary construction unit, e.g. a motor car frame. In view of facilitating the closing operation of the boot lid, the pressure in the gas spring is sometimes selected such that the gas spring cannot fully overcome the gravitational forces acting onto the boot lid. In such cases the gas spring cannot fulfill the function of maintaining the boot lid in the upper terminal, i.e. the fully opened position without additional provision. In order to enable the gas spring to maintain the boot lid in the upper terminal position, the gas spring is constructed such that in the outer terminal position of the piston rod with respect to the cylinder an increased resistance is exerted by the gas spring against pushing the piston rod inwards of the cylinder. A simple and economic hydraulic circuit is proposed in view of achieving such increased resistance.

Abstract: In a cylinder piston device two working chambers on both sides of a piston are interconnected by a fluid passage. This fluid passage includes in series a first passage section and a second passage section. The first passage section comprises a first bore and a second bore in parallel. The first bore is always open. The second bore is opened and closed by a throttling valve body in response to the direction of axial movement of the piston. The second passage section is opened or closed selectively by a closure body controlled from outside the cylinder.

Abstract: The piston cylinder type damper comprises a cylinder connected to either member of the pair of a main body and an openable object, and a piston connected to the other member of the pair and adapted to fit into the cylinder and the piston incorporates therein a check valve adapted to allow the air in the cylinder to escape from the cylinder interior while the piston is driven into the cylinder by the movement of the openable object.

Abstract: A mechanical locking device for restraining the piston rod of a gas spring n an extended position comprises a lock tube mounted on the piston rod coaxially with the cylinder and adapted to ride telescopingly over the cylinder during normal inward and outward movement of the piston rod. Apparatus is provided on the piston rod whereby the piston rod can be overextended, beyond its normal fully extended position, to permit the lock tube to move out of coaxial alignment with the cylinder; the end of the lock tube thereby abuts the end face of the cylinder and prevents inward movement of the piston rod.

Abstract: A suspension and steerage system is disclosed for a wheel supported vehicle. A suspension arm assembly of parallelogram configuration is pivotally attached to one side of the main frame and freely supports a wheel spindle. The piston rod of a hydraulic motor interconnects opposite wheels, and a lever structure is provided which, in response to pivotal oscillation of one wheel, axially activates the piston rod to transfer reactive forces to the opposite side of the main frame, and serves to level the plane of the main frame. The hydraulic motor can further be equallized to lock out further movement of the wheels, thereby stabilizing the vehicle in a static condition.

Abstract: A fluid-operated actuating device of the type including an actuating cylinder member, an axially movable actuating piston rod member, and actuating fluid connection means for introducing actuating fluid to and removing actuating fluid from the actuating cylinder member so as to adjust the relative axial position of the actuating cylinder and piston members and including structure for damping the movement of the piston rod member with respect to the cylinder member.

Abstract: A tilt-lock mechanism for a vertically tiltable outboard stern drive on a marine vessel preferably includes a hydraulic cylinder device dampingly connecting the drive unit and the vessel. The mechanism preferably includes apparatus allowing the operator to selectively prevent or allow the drive unit to freely tilt under various operating conditions.

Abstract: An anti-surge valve for installation in a cylindrical chamber permits a fluid to flow at low velocity into and out of a port that opens into the cylindrical chamber and is located on the concave wall of the cylindrical chamber, the valve preventing a high velocity flow of the fluid from the cylindrical chamber into the port. The valve includes a sealing tube that is positioned within the cylindrical chamber in juxtaposition with the port and coaxial with but spaced radially inward from the portions of the concave wall that surround the port. The sealing tube is maintained in this position by spacers surrounding the sealing tube and extending radially outwardly to the inner surface of the cylindrical chamber. The anti-surge valve is a unitary structure molded of rubber.

Abstract: A gas spring comprising a cylinder, a rod slidably extending from the cylinder, and a novel locking mechanism. The mechanism comprises first and second axially contiguous recesses in the circumference of the rod, a locking member normally located in the first recess and snappingly and rockingly movable between two recesses, and axially spaced first and second actuating members cooperating with the locking member. The first actuating member comprises an engaging portion and a releasing portion being circumferentially spaced therefrom. The releasing portion acts to displace the locking member to the second recess. The second actuating member comprises an engaging portion for locking the rod and also for displacing the locking member to the first recess, and axially and circumferentially inclined guide walls for circumferentially displacing the locking member thereby guiding the same between the releasing portion and engaging portions in response to the movement of the rod.

Abstract: Full extension locking device which securely maintains the fully extended state of the stay damper, etc. for closing and opening of the back door of a car and which assures smooth contraction of the damper when an external force is added. An elastic cover along the cylinder is fixed to the piston rod and this cover is deformed and blocked by the stopper provided on the cylinder at the time of full extension of the damper, and the locking is released at the time of contraction. It is possible to see whether the lock is working or not at the time of full extension locking, and there is no danger of hands being caught or hurt when the lock is released, and also the structure is simplified.

Abstract: A gas spring for height adjustment of drawing-tables or the like includes an arrangement for hydraulically locking the gas spring against sudden collapse due to overloading or loss of internal gas pressure. The hydraulic locking mechanism includes a pressure responsive valve which operates, in response to an excess pressure differential between the gas spring cavity and the pressurized gas chamber, either to prevent flow of the hydraulic locking medium out of the cylinder cavity or to restrict such flow to a slow, safe rate.

Abstract: An extensible strut such as a gas spring and having a cylinder, a rod guided by the cylinder and slidably extending through one end of the cylinder to the outside, and a locking mechanism for locking the rod at an extended position.

Abstract: A lengthwise adjustable gas spring consists of a housing containing gas under pressure, which is formed by an outer tube 2 and a coaxially disposed inner tube 3 with an annular channel 4 therebetween. A closed piston 5 sealed against the inner tube and axially movable within same, is connected to a piston rod 9, which extends through a seal formed by a plug 10 at one end of the housing. A valve 23 is disposed at the other end of the housing and is used for the regulated connection via the annular channel 4 of two partial housing chambers 20a and 20b disposed on either side of the piston within the inner area of the housing. A valve lifter 22 is embodied within the valve body and is sealed against the valve body and opens or closes gas transfer ports. The valve body 23 and the plug 10 are axially supported against the inner tube 3 and are sealed against the inner surface of the outer tube 2. In order to avoid use of separate seals, the valve body e.g.

Abstract: A lock-out apparatus for shock absorbing draft gear on a railway car which draft gear has a housing adapted to be fixed to one end of the railway car, a shock absorber is provided in the housing to cushion shock on the coupler of a railway car at the one end. The shock absorber includes at least one movable shock absorbing member operatively connected to the coupler and a cushion cooperating with the movable member to cushion shock. The lock-out apparatus has a locking member slidably mounted in the housing for movement between a locking and an unlocking position. There is a fluid motor for moving the locking member, and a conduit connecting the fluid motor to a brake line on the railway car whereby a change in the pressure of the fluid in the brake line will operate the fluid motor to move the locking member to a locking position to prevent movement of the movable shock absorbing member and to thus lock out the draw gear.

Abstract: A pneumatic spring for use, for example, as a lifting device or support strut for a chair or the like with provision for the adjustment of axial extent. The pneumatic spring is substantially composed of a telescoping cylinder-piston assembly containing a gas and/or fluid under compression. A releasable valve assembly permits the relative position of the piston with respect to the housing to be adjusted arbitrarily. In order to provide for a terminal spring stiffening in the position of near full insertion of the piston rod, the invention provides that a pin extending from the main piston enters a central volume which is thereby sealed off from the remainder of the internal volume. Accordingly, the gas in the remaining available volume is compressed more highly and exerts an increased opposing force on the primary piston during its final insertion.

Abstract: In the illustrative embodiments of the invention described, a gas spring useful as a height-adjustment and weight-compensation device, as, for example, in a height-adjustable table, includes structure that is responsive to the drop in gas pressure within the primary cylinder below a predetermined level to lock or brake the piston rod against abrupt movement with respect to the primary cylinder if a compressive load is thereafter applied to the gas spring. The pressure-responsive structure preferably includes a sealed auxiliary cylinder-piston unit carried by the piston rod internally of the gas spring. The auxiliary unit contains a separate pressurized body of gas, and either the auxiliary cylinder or piston is axially movable, in response to the greater internal pressure within the auxiliary unit when gas pressure within the primary cylinder drops too low, to engage the locking or braking device.

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.