Abstract: A column which includes an elongated guide tube receiving a pneumatic spring of the piston-and-cylinder type in its bore. A bar is fixedly fastened to the piston rod member or the cylinder member of the spring in longitudinal alignment and extends in the guide tube bore from the associated spring member toward one of the two longitudinally terminal parts of the guide tube. A spring assembly extending about the bar is interposed between spring seats on the pneumatic spring member fixedly fastened to the bar and the one terminal part of the guide tube. Cooperating abutments on the bar and on the one terminal part of the guide tube limit movement of the bar toward the other longitudinally terminal part of the guide tube.

Abstract: A gas spring includes a cylinder, filled with compressed gas, a piston rod movable axially inward and outward of the cylinder cavity, and a piston axially movable on the end of the piston rod in the cavity and resiliently biased into engagement with an abutment on the free end of the piston rod. One of two passages bounded by the piston and connecting the two compartments into which the cylinder cavity is divided by the piston is blocked when the piston engages the abutment and opened when the piston is moved away from the abutment against the resilient bias. The other passage is opened during outward movement of the piston rod from the cylinder cavity.

Abstract: A telescopic spring has an outer spring member and an inner spring member movable inward and outward of a cavity in the outer spring member. Fasteners on the spring members outside the cavity permit the spring members to be fastened to respective objects. A compressed gas in the cavity outwardly biases the inner spring member. One of the spring members carries a contact element which engages a conductive face portion of the inner spring member during one portion of the movement of the inner spring member. Insulating matter insulates the contact element from the conductive face portion during another portion of the movement. Two electrical connectors outside the cavity are conductively connected to the contact element and the conductive face portion respectively.

Abstract: A gas spring includes a cylinder having two axial portions of different cross section and two pistons mounted on a common piston rod and respectively matching the cross sections of the cylinder portions. The pistons are spaced on the piston rod so that they are either both in the wider cylinder portion or respectively received in the two portions. A first throttling passage permits flow of fluid between the two cylinder compartments separated by the larger piston, and a second throttling passage by-passes the smaller piston only during movement inward of the smaller cylinder portion to permit flow of fluid out of that cylinder portion. A valve arrangement is biased for sealing the two parts of the cylinder cavity separated by the smaller piston when the latter is in the smaller cylinder portion, but does not move inward of that portion. The valve arrangement responds to a sufficient, axially applied force for connecting the two cavity parts.

Abstract: A column in which an inner elongated member of circular cross section is partly received in the polygonal bore of an outer, tubular member and secured against angular displacement about the common axis by guide elements secured against longitudinal movement in respective recesses of the inner member open toward the outer member and engaging the outer member in respective corners of its polygonal cross section. A manually controlled arresting mechanism permits the two column members to be arrested against relative longitudinal movement in a multiplicity of relative positions.

Abstract: The piston in a gas spring of the piston-and-cylinder type is prevented from moving from one of its terminal positions under the pressure of the gas in the cylinder by a plunger on the piston projecting toward the closed cylinder end and received in an axial recess of a brake member on the cylinder by cooperating engagement elements on the plunger and brake member which may provide a friction fit or impede fluid flow into the recess.

Abstract: A pneumatic spring conductively connecting a heater on the window pane in the tail gate of a station wagon to a battery is mounted between ball-and-socket joints whose plastic socket parts are equipped with barbs permitting insertion of the ball part without tools, but preventing accidental release.

Abstract: The cylinder cavity of a pneumatic suspension element of the piston-and-cylinder type in which the escape of compressed gas from the cylinder cavity is prevented by a liquid in a portion of the cylinder cavity through which the piston rod passes is charged with compressed gas and liquid through resiliently sealed gaps about the piston rod and/or through a porous partition separating the liquid-filled cavity portion from the gas-filled portion.

Abstract: A column including a cylinder, a piston axially slidable in the cylinder cavity, a piston rod axially projecting from the cylinder, and a valve permitting selective communication between the two compartments of the cylinder cavity separated by the piston for flow of fluid between the compartments is additionally provided with a helical compression spring coiled about the piston rod and impeding axial movement of the piston on the piston rod in one direction, movement in the other direction being limited by a radial abutment flange on the piston rod. The spring favorably affects the comfort of a chair whose seat is mounted on the column.

Abstract: In a gas spring having a cylinder and a piston rod movable within the cylinder, braking elements are provided which brake or block the movement of the piston rod with respect to the cylinder when the interior pressure within the cylinder is reduced below a predetermined pressure. So the risk is eliminated that the piston rod when under load is unintentionally moved into the cylinder with a high velocity when the gas pressure within the cylinder is lowered below the predetermined pressure. The braking elements are spring loaded and are held in an inoperative position by adequate pressure within the cylinder.

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: The height of a chair and the inclination of its back support may be varied by changing the respective, effective lengths of two pneumatic springs whose assembly forms the chair leg. The cylinder of one spring is coaxially received in the cylinder or the hollow piston rod of the other spring, and relative axial movement of the received spring and the receiving element of the other spring is limited or entirely prevented. A valve connects the two compartments separated in the cylinder of each spring and may be operated by a mechanism separate from the valve operating mechanism of the other spring.

Abstract: The piston rod of a pneumatic spring is expelled from the cylinder by compressed fluid in the cylinder until a normally open channel connecting two compartments of the cylinder cavity on opposite axial sides of the piston is blocked by cooperating valve elements on the cylinder and on the piston assembly.

Abstract: A pneumatic suspension element of the piston-and-cylinder type in which the escape of compressed gas from the cylinder cavity is prevented by a liquid in a portion of the cylinder cavity through which the piston rod passes. The compressed gas and liquid are introduced into the cylinder cavity through resiliently sealed gaps about the piston rod and/or through a porous partition separating the liquid-filled cavity portion from the gas-filled portion.

Abstract: A pneumatic spring of the piston-and-cylinder type for use with the engine compartment hood or trunk lid of a motorcar and subject to explosive destruction in the event of an engine fire or a collision is provided with frangible, reduced wall portions in the cylinder and/or in the tubular piston rod which yields under excessive stresses and releases the compressed gas from the cylinder under conditions in which it cannot propel pieces of the fractured spring at high velocity.

Abstract: A gas spring of the cylinder-and-piston type having a throttling passage in the piston has a cup-shaped receptacle coaxially mounted on the piston about the piston rod and a plunger mounted on the annular end wall of the cylinder through which the piston rod passes. The plunger enters the receptacle when the piston rod approaches the outer end of its stroke, and fluid can be displaced by the plunger from the receptacle only through a narrow gap between respective walls of the plunger and receptacle for supplemental damping action.

Abstract: A pneumatic spring of the piston-and-cylinder type suitable for balancing the trunk lid of a motorcar and like applications is equipped with a stop mechanism which stops relative axial movement of the piston or piston rod and of the cylinder in response to a force axially applied to the spring, but releases the cylinder and piston or piston rod from each other in response to an applied force greater than the first-mentioned force. Cooperating stop members on the cylinder and piston rod engage each other as long as the relative axial movement of the principal spring elements is stopped.

Abstract: In a column of telescopically adjustable height, the two coaxial telescoping members may be adjusted axially after a control button in an axial bore of one member is depressed. A bracket, longitudinally split into two members, passes into the bore through a radial opening of the one column member and is anchored axially and radially by conforming engagement with the column member. The operating lever for the control button is pivoted between the bracket members outside the column bore so that a small angular movement of the exposed lever part causes the terminal part of the lever in the bore abuttingly to engage the control button and to depress the same.

Abstract: In a pneumatic spring of adjustable length, the piston rod is sealed to the cylinder by an annular sealing disc stressed in compression between the inner cylinder wall and a rigid, tubular projection on the radial end wall of the cylinder through which the piston rod extends outward of the cylinder cavity. The sealing disc is axially longer than the projection so that it extends inward of the cavity beyond the projection and carries an annular sealing lip engaging the piston rod only under the fluid pressure in the cylinder cavity, but practically fully relieved by the annular projection from the compressive stresses.