Abstract: An active shock-absorbing boat seat system has a seat system mounted to the boat deck through an active shock absorber. Sensors monitor both the shock to be passed from the deck to the seat as well as the shock actually received by the seat after passing through the shock absorbing system. A controller monitors the shock levels and provides a continuing control signal to the shock-absorbing unit to control the response of the shock-absorbing unit during the duration of the shock. The control system can provide for adjustment of various operating parameters for the system, including initial position of the seating system, overall ride stiffness, maximum allowable shock, and other parameters.

Abstract: A pneumatic seat suspension assembly including upper and lower support members with scissors linkages extending therebetween, a pneumatic spring operatively attached between one set of opposing parallel scissors arms, a height adjuster in communication with the pneumatic spring, a dump valve in communication with the pneumatic spring and a safety rollover valve in communication with the pneumatic spring. The scissors linkage provides the mechanical connection between the seat bottom and the seat support while the pneumatic spring provides the structure to raise and lower the seat bottom by use of compressed air which causes the parallel scissors linkages to be pushed upward causing the seat to rise.

Abstract: According to the present invention, a ride zone protection device is provided for use with a pneumatic seat suspension, comprising a cam in communication with the air suspension actuation means to alternatively allow and prevent actuation of the air suspension based on the positioning of the vehicle seat.

Abstract: A snowmobile seat suspension includes a seat support member pivotally connected at its front end to the chassis of a snowmobile, a yieldable support member supporting the rear of the seat support member and at least one air cylinder yieldable in a downward direction but damping in the upward direction. The air cylinder is connected to an inlet hose having a length of 1 to 6 inches, the hose containing a one-way valve which allows air to enter the cylinder without restriction but restricts outflow of air from the cylinder.

Abstract: A rollover vent valve for use in a pneumatic seat mounted in a vehicle. The rollover vent valve allows air to vent from the air bag(s) in the pneumatic seat in the event the vehicle in which the seat is mounted is severely tilted or overturned. The rollover vent valve includes a housing enclosing a pressure chamber and a valve member. The interior of the pressure chamber is in fluid connection with the air bag(s). The rollover vent valve also includes a vent port that connects the interior of the chamber to the ambient environment. The valve member is located within the pressure chamber above the vent port and forms a seal with the vent port when the pneumatic seat in which the valve is mounted is in an upright position. The valve member includes a weight cage in which a spherical weight is movably mounted. One end of the weight cage includes a valve seal that forms a seal on the valve seat of the vent port.

Abstract: An orientation-sensitive pressure release for the airbag (15) of a vehicular pneumatic seat (11) that includes a rollover valve (21) mounted in the air inlet line of the pneumatic seat is disclosed. The valve (21) releases air from the pneumatic seat (11) when the valve is tilted or overturned, which occurs when the vehicle is tilted or overturned. The valve includes a spring-loaded poppet (43) that encloses an exhaust port (41). Attached to the poppet is a downwardly extending whisker (65) that extends into an inverted conical cup (64). A conically shaped element (78) is affixed to the lower end of the whisker (65). Housed in the inverted conical cup is a relatively heavy ball (67). When the valve (21) is tilted or overturned, the ball (67) hits the side of the conically shaped element (78) causing the whisker (65) to tilt and the spring-loaded poppet (43) to open the exhaust port. Opening the exhaust port (41) releases air from the air bag (15).

Abstract: An energy-absorbing apparatus for a bicycle frame maintains critical spatial relationships by allowing the seat and the pedal assembly to move slightly, together as a unit, relative to the bicycle frame proper. A telescoping portion of the apparatus has an inner tube housed inside an outer tube. The inner tube has a seat post connected to its top end and a pedal crank axle housing connected to the bottom end. The outer tube is in a fixed, integral relationship with the other frame members. Any of a number of combinations and variations of adjustable spring/damper means isolate the inner tube from the outer tube. Numerous features, including dust boots and a rider-activated keyway lock, can be incorporated into the frame design. The telescoping design reduces impact forces without causing undesirable changes in frame geometry or undesirable changes in the distance between the seat and pedals.

Abstract: An active seat suspension system for equipment that transfers vibration to a human operator provides human body vibration control and, thus, a more comfortable environment for the operator. The system utilizes a "man in a loop" control strategy, where both the equipment and human operator model are analyzed as a dynamic system. The seat suspension parameters are evaluated through optimization, which assumes, under normal stochastic conditions, that the vibratory inputs to the system are unknown. A controller estimates their values in real time, and a preferred characteristic force between the seat and machinery is determined. The characteristic force determined minimizes a cost function. Using an output from the controller, an actuator (which may be either active or semi-active) substantially applies the characteristic force between the seat and machinery, resulting in reduced vibration being transmitted to the human operator.

Abstract: A bicycle seatpost with an integrated pivotal suspension system. The seatpost has a lower piece and an upper piece joined by a pivot pin which allows the upper piece to rotate in a rearward and downward direction. A spring is interposed between the upper piece and the lower piece to provide resilient suspension.

Abstract: A shock absorbing seat is provided in a personal watercraft or boat. The seat has an elongated configuration and is mounted at the front end thereof to the hull or other structural member of the watercraft for limited pivoting motion relative to the hull or structural member. A shock absorber assembly which includes a fluid filled cylinder, a piston therein, and a coil spring externally mounted to the cylinder piston combination, or an elastic envelope filled with pressurized air, is mounted for limited motion relative to the hull or other structural member of the watercraft, and to the seat so as to support at least a substantial portion of the weight of the seat and occupant thereof, and to absorb forces generated between the hull and the seat while the watercraft is in motion.

Abstract: A seat suspension system for supporting a seat support member on a base member includes support arms which cooperate with a spring suspension so as to suspend loads imposed on the seat. The support arms are connected to one of the seat support member and base member by a support mechanism. A cam element acts upon at least one of the seat support member and the base member and presents a cam surface offering a resistance to the motion of the accompanying cam follower which varies depending upon the height of the seat support member. The system preferably includes a height adjust mechanism for adjusting the unloaded distance between the seat support member and the base member. The height adjust mechanism may be either a ratchet mechanism which is operated by lifting the seat support member, or a spring assisted mechanism which is operable independently of the main suspension springs and which automatically biases an unloaded seat support member upwardly.

Abstract: A seat suspension is provided that has a damper unit which is connected between the seat and the chassis on which the seat is mounted. The damper can be switched between soft and hard settings. The damper switching is controlled based on the relative position of the seat and one of the relative or absolute velocity of the seat. When the seat and the chassis are moving in the same direction the damper is set to soft, (producing a low damping effect), while when the seat and chassis are moving in opposite directions the damper is switched to hard (producing a high damping effect).

Abstract: A shock absorbing seat is provided in a personal watercraft or boat. The seat has an elongated configuration and is mounted at the front end thereof to the hull or other structural member of the watercraft for limited pivoting motion relative to the hull or structural member. A shock absorber assembly which includes a fluid filled cylinder, a piston therein, and a coil spring externally mounted to the cylinder piston combination, is mounted for limited motion relative to the hull or other structural member of the watercraft, and to the seat so as to support at least a substantial portion of the weight of the seat and occupant thereof, and to absorb forces generated between the hull and the seat while the watercraft is in motion.

Abstract: A seat suspension device for an automotive seat, in which an upper frame is movably connected with a lower frame via an X-shaped link in a vertically movable manner, with the arrangement that an upwardly curved section is formed at the frontal part of the upper frame whereas a downwardly curved section is formed at the frontal part of the lower frame, and that a damper is interposed vertically between those upwardly and downwardly curved sections.

Abstract: A vibration dampening suspension device for isolating a truck cab from the force vibrations of a vehicle frame, which includes an impact plate mounted to the truck cab, and a support plate mounted to the vehicle suspension. The device further includes a link member pivotally interconnected at one end with the support plate at a support pivot, and a lever member with a first end pivotally interconnected with the impact plate at a main pivot. The link member is pivotally interconnected with the lever member for rotation of the lever member with respect to the main pivot during compression of the shock absorber when the supporting body, suspended body and device are in a dynamic condition. A hydraulic shock absorber is provided with a first end pivotally interconnected with the lever member second end at a shock pivot and the second end pivotally interconnected with the impact plate at a pivot spaced from the main pivot.

Abstract: A pneumatic spring for damping the relative motion between a vehicle seat and a base upon which the seat is mounted utilizes a rolling lobe sleeve, a plug secured within one end of the sleeve and a piston secured within the other end of the sleeve for movement toward and away from the plug as the sleeve rolls along the outside surface of the piston. The piston, sleeve and plug provide the surfaces of a variable-volume chamber, and the piston includes an internal piston cavity of a fixed size and shape. The variable-volume chamber and piston cavity contain a pneumatic fluid, and an orifice is provided within the piston which permits flow communication between the variable-volume chamber and the piston cavity.

Abstract: A vehicle seat suspension unit has a base frame mountable in a vehicle and seat support frame on which is mounted a vehicle seat. A scissor-arm assembly, with primary links and secondary links, interconnect the frames overlapping cam tracks, with cam profiles engaged by rollers attached to main springs anchored on the base frame. As the frames move towards each other, the main springs are extended as the rollers move along the cam tracks to apply a restoring force to the frames. A preload assembly has rocker arms, pivotally mounted on the cam tracks, with rollers bearing on the seat support frame and provided with preload springs. By adjustment of the cam tracks relative to the base frame, the preload and the main spring rate can be varied to suit the operator's weight.

Abstract: In a lockable elevating mechanism for the continuous adjustment of chair seats a guide tube is provided, to the bottom plate of which is secured a piston rod of a longitudinally adjustable gas spring. The guide tube is provided with an additional tube, which can be exited telescopically and and which is guided in a guide bush arrested in the guide tube. The housing of the gas spring is in turn guided in a guide bush arrested in the additional tube. A mechanical spring is provided between the guide tube and the additional tube and acts upon the additional tube in a direction out of the guide tube.

Abstract: An adjustable rocker spring apparatus for adjustably positioning a rocker block of a rocking chair relative to a stationary base of the chair. The apparatus generally comprises an L-shaped upper bracket and an L-shaped lower bracket each having forward, central and rearward portions. Each such forward, central and rearward portion include a plurality of apertures therein. A pair of independent coil springs are disposed between portions of the upper and lower brackets and secured thereto by tabs. The independent coil springs are alignably maintained and positioned by slot openings in lip portions of each of the L-shaped upper and lower brackets. The plurality of independent apertures in each of the forward, central and rearward portions of the upper and lower brackets enable the apparatus to be adjustably secured with conventional fasteners to a rocker block and stationary base of a rocking chair.

Abstract: A controller is provided for seating, and the like, such as chairs of the type that have a stationary base or support, and a back which tilts about a generally horizontal axis with respect to the support. The controller includes an adjustable tension device, and a shared-load arrangement, which readily adapt the chair for different users and various applications. The adjustable tension device comprises a spring, having one end operably connected with a support, and the other end operably engaging the back at selected locations spaced apart from the tilt axis, such that rearward tilting of the chair back deflects the spring, and thereby generates a torque or back tension which resists further tilting. A shifter moves the other end of the spring between the selected back locations to vary the lever arm at which the spring acts, and thereby adjusts back tension.

Abstract: A mechanical seat suspension inside a housing comprises parallel scissor arms and a support arm with a cam connected to suspension springs. The support arm, which carries the substantial majority of the seat load, has a height adjustment mechanism and a cam with two arcuate surfaces that define an imaginary pivot point. The use of the cam with the imaginary pivot point permits a more compact structure. Various embodiments of the support arm with a cam end and devices using the support arm are also disclosed. A shock absorber attached to the outside of the scissor arms dampens the stroke of the suspension springs connected to the cam. The ratio of the shock stroke travel to the vertical movement of the seat remains generally linear and constant, thus producing a more comfortable ride. Also included is a height adjustment mechanism on the support arm that interlocks with the cam by a pivoting pawl and biasing spring.

Abstract: A longitudinally controllable adjustment device comprises a cylindrical housing, in which a piston rod with a piston is slidable and sealingly extending outwards. Furthermore it comprises a valve for controlling length adjustment of the device. In order to avoid a destruction of seals preventing a flow to the outside of pressure medium at least two seals are provided between the housing and the piston rod whereby a seal between the outer end of the housing and a further seal prevents an inflow of gas and in particular of liquid from the outside into the housing.

Abstract: A device for adjusting and locking the inclination of the backrest of a seat, for example an aircraft seat, comprises a gas compression spring which acts between the back rest and the frame of the seat and which is of the type which has a locking and release member, which, when pressed frees the spring to expand or to be compressed and when released locks the spring in any position in which it is set to lock the back rest. The locking and release member is operated by a button fitted in an arm rest of the seat. To enable the button to operate the locking and release member entirely mechanically, the button is connected to one end of a Bowden cable through a first lever and the other end of the Bowden cable is connected to the locking and release member through a second lever. The two levers together provide a mechanical advantage of 8:1 between the force applied to the button and that acting on the locking and release member.

Abstract: A controller is provided for seating, and the like, such as chairs of the type that have a stationary base or support, and a back which tilts about a generally horizontal axis with respect to the support. The controller includes an adjustable tension device, and a shared-load arrangement, which readily adapt the chair for different users and various applications. The adjustable tension device comprises a spring, having one end operably connected with a support, and the other end operably engaging the back at selected locations spaced apart from the tilt axis, such that rearward tilting of the chair back deflects the spring, and thereby generates a torque or back tension which resists further tilting. A shifter moves the other end of the spring between the selected back locations to vary the lever arm at which the spring acts, and thereby adjusts back tension.

Abstract: A vehicle seat mounting structure includes a base, a seat mount, and a mechanism operably interposed between the base and mount for controlling relative motion thereof. The mechanism includes a platform, air springs to cushion roadway induced shock, and linkage arms to couple the base, seat mount and platform. The mechanism produces a rearward tilting of a seat which is mounted on the structure when vehicle movement tends to throw the seat toward the front of the mounting structure.

Abstract: A device for adjusting the inclination of the backrest and/or seat of chairs, particularly office chairs, has a gas spring, a head member connectable to the gas spring, an L-shaped lever member pivotally connected to the head member and including a first arm, a second arm, and a rod acting on the first arm so as to cause rotation of the L-shaped member and consequent pushing action of the second arm on the driving shaft of the valve of the gas spring.

Abstract: An air suspension device for a vehicle seat which is capable of automatic adjustment of the height of the seat at a given neutral position. In the device, an air spring is adjusted in flow of air thereinto or therefrom via a directional control valve which is actuated responsive to the vertical movements of link members, so as to adjust the height of the seat. A play is provided in the interlocking relation between the control valve and link members to avoid unnecessary actuation of the valve. Further, a manual control valve is disposed between an air source and the air spring, with a check or shuttle valve provided therein, thereby forming a direct air exhaust circuit, whereby operating the manual valve effects a rapid exhaust of air from the air spring, not via the directional control valve.

Abstract: A mechanical seat suspension inside a housing comprises parallel scissor arms and a support arm with a cam connected to suspension springs. The support arm, which carries the substantial majority of the seat load, has a height adjustment means and a cam with two arcuate surfaces that define an imaginary pivot point. The use of the cam with the imaginary pivot point permits a more compact structure. Various embodiments of the support arm with a cam end and devices using the support arm are also disclosed. A shock absorber attached to the outside of the scissor arms dampens the stroke of the suspension springs connected to the cam. The ratio of the shock stroke travel to the vertical movement of the seat remains generally linear and constant, thus producing a more comfortable ride. Also included is a height adjustment mechanism on the support arm that interlocks with the cam by a pivoting pawl and biasing spring.

Abstract: Herein disclosed is a shock absorbing device for a vehicular seat. The device comprises a link mechanism having lower and upper base members which are movable toward and away from each other; and a shock damper interposed between the lower and upper base members to damp shocks or vibrations applied to the same. The shock damper includes an axially expandable housing having lower and upper parts which are respectively secured to the lower and upper base members of the link mechanism; a diaphragm disposed in the housing to partition an interior of the housing into an air-filled part and a liquid-filled part; a partition wall disposed in the liquid-filled part to partition the same into first and second chambers, the partition wall having an aperture formed therethrough; and an orifice member axially movably disposed in the aperture of the partition wall, the orifice member having an orifice formed therethrough.

Abstract: A multi-purpose patient support and transport apparatus is provided which includes a Trendelenburg mechanism and a novel guard rail assembly. The Trendelenburg mechanism is actuated by turning a handle in one direction. This allows a pneumatic spring connected between the seat and backrest assemblies to be fully contracted, thereby moving the backrest assembly to a Trendelenburg position. When the handle is turned in the opposite direction, the backrest may also be rotated downwardly, but is precluded from moving beyond the reclining position by a stop member which prevents the pneumatic spring shaft from moving entirely within the spring casing. The guard rail is mounted to the frame of the apparatus by a pair of pivot arms extending at an oblique angle with respect to the plane of the rail. This allows the rail to be stored under the frame when in the lowered position.

Abstract: A mechanical seat suspension inside a housing includes parallel scissor arms and a support arm with a cam connected to suspension springs. The support arm, which carries the substantial majority of the seat load, has a height adjustment assembly and a cam with two arcuate surfaces that define an imaginary pivot point. The use of the cam with the imaginary pivot point permits a more compact structure. A shock absorber attached to the outside of the scissor arms dampens the stroke of the suspension springs connected to the cam. The ratio of the shock stroke travel to the vertical movement of the seat remains generally linear and constant, thus producing a more comfortable rids. Also included is a height adjustment mechanism on the support arm that interlocks with the cam by a pivoting pawl and biasing spring. The height of the seat is adjusted by the relative movement of the top portion of the housing to the lower portion. No external levers, triggers, or other structures are necessary for seat adjustment.

Abstract: A damper assembly, for supporting a seat of a vehicle such as a small-sized motor boat, comprises a lower bracket adapted to be attached to a floor of the vehicle, an upper bracket adapted to be attached to the seat, and a damper mounted between the upper and lower brackets. The damper includes an outer tube extending upwardly from the lower bracket, an inner tube extending downwardly from the upper bracket and telescopically inserted in the outer tube, and a guide tube secured to the lower bracket and telescopically inserted in the inner tube. The inner and guide tubes are connected together so as to allow the inner tube to slide longitudinally on the guide tube but so as to prevent the inner tube from rotation or turning about the guide tube.

Abstract: A fluid pressure actuated assembly includes a casing made of a flexible resilient material, such as rubber or polyurethane, a coiled tension spring sleeved on the casing for biasing the casing to move toward a retracted position, and a coiled spacing spring interposed between the tension spring and the casing for preventing any wall of the casing from being clamped between any two adjacent turns of the tension spring. When a compressed fluid is applied to the interior of the casing, the casing extends.

Abstract: A positioning device is used for the positioning of a chair seat as to its inclination, or for positioning a back-rest member of a chair. The positioning device is constructed such as usual hydropneumatic springs which can be locked by closing a passage connected to working chambers on both sides of a piston. The working chambers are filled with an operating liquid. In order to adapt the biasing force of such a positioning device, one of the working chambers is conneced with a force-measuring device, which force measuring device is provided within the force transmission path of the respective chair column. The force measuring device comprises a measuring space filled with operating liquid, and this operating liquid is in liquid connection with one of the working chambers.

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 support column for height-adjustable seats is described, in which the tubular support element housing the guide bush of the seat raising element and the relative control mechanism is formed from a plastic coupling element which is provided externally with a Morse taper for fixing the column to the seat support base, and is connected in an axially rigid manner to the guide bush so as to fix it into the support element, and from a strengthening element in the form of an unworked tube mounted surrounding the coupling element.

Abstract: A seat suspension for resiliently attaching a seat assembly to a support frame on a vehicle so as to cushion the ride for the seat occupant comprises: main biasing springs operatively connected between the seat assembly and support frame to initially absorb energy and limit descent as the seat assembly is forced downward; auxiliary biasing springs, including a "hard" spring and a "soft" spring, to subsequently absorb energy and further limit descent after the main springs have been compressed a predetermined amount; and a shock absorber connected between the seat assembly and support frame to dampen vertical motion. A preloading apparatus is provided for adjusting or preloading the main biasing springs to take into account the weight of the seat occupant. A height adjusting apparatus is provided to adjust the height of the seat assembly and associated biasing springs relative to the support frame.

Abstract: A device for monitoring the operation of pneumatic seats for vehicles, the seats being supported by a pneumatically-operated spring to give a resilient seat mounting.The monitoring device operates at the commencement of use of the seat and also during use of the seat in case of possible leaks of air.Sensing elements are located at positions above and below a rated central position and are actuated according to movements of the seat from the centralposition. Actuation the sensing elements provides signals for a counter device which when an upper or lower limiting value is reached automatically resets itself to a starting value between the two limiting values and emits a control signal corresponding to the limiting value reached. The control signal operates an air valve for a predetermined length of time to supply air to or discharge air from the pneumatic spring.

Abstract: A hydropneumatic spring in which a casing filled with fluid under pressure is selectively movable with respect to a piston contained within the casing and mounted on a stationary hollow support rod. The piston divides the casing into an upper and lower chamber. When the fluid path is unlocked or opened and the casing is subjected to axial pressure, fluid passes from one chamber to the other through the hollow support rod and axially through the piston.

Abstract: In a gas pressure spring for a chair, a locking device is provided, which includes a safety sleeve formed of two semi-circular halves which are clamped on an outer tube of the gas pressure spring by clamping bolts. The outer tube is formed with an end portion of a reduced diameter and a transition zone. The two halves of the safety sleeve are formed each with an inner collar matching the transition zone of the outer tube. One of the halves is formed with a through opening for passing a height-adjusting lever towards the outer tube.

Abstract: A system for resiliently supporting a load at a reference height includes a hydraulic cylinder for resiliently supporting a load about a reference height and an accumulator which cooperates with the cylinder for flowing hydraulic fluid therebetween in response to varying loads imposed on the cylinder. A valve is provided for dampening the rate of fluid flowing between the cylinder and the accumulator and a metering valve coacts with the cylinder for adjusting the reference height about which the load is supported.

Abstract: A power unit for medical and like stools and chairs, the first disclosed power unit comprising a post assembly comprising a cylinder, a ram or piston tube which telescopes within the cylinder and a reservoir containing oil under pressure of compressed air, which reservoir is carried by and wrapped slenderly and cylindrically around the lower part of the ram. A dip tube in the reservoir accommodates oil flow across a two piece interiorly and exteriorly sealed plastic control valve disposed in the hollow of the ram, adjacent the top of the reservoir, by which (a) the effective length of the power unit is extended and retracted depending on whether the weight of the user is imposed on a seat carried by the upper end of the ram tube when the control valve is caused to be opened by manual manipulation of a lever pivotally secured to the ram tube above the control valve and (b) any selected length is retained when the control valve is closed.

Abstract: A vehicle seat having a seat base frame (10) mounted on cross rails (12) is provided with a height adjustment mechanism comprising a pair of generally U-shaped leaf springs (14) which constitute the sole support for the seat on the crossrails (12). The leaf springs each have a pair of oppositely inclined upstanding tongues (18) connected to the seat base frame through pin and slot connections (32, 34) and, adjacent their upper ends, each pair of tongues (18) is connected by a rod (37) which serves both to stiffen the tongues (18) and also to effect adjustment of their inclination so as to vary the height of the seat base (10) above the rails (12).

Abstract: A device for supporting a chair at a selected height, comprising a hydraulic cylinder operative to support the chair, the cylinder being contractable to lower the chair under the weight of the chair occupant and being subject to a spring bias which extends the cylinder to raise the chair when unoccupied. The cylinder comprises two fluid-filled chambers separated by a valve. The fluid flows between the chambers via the open valve during expansion and contraction of the cylinder, and the valve when closed blocks the fluid flow whereby to hydraulically lock the cylinder. The hydraulic fluid is preferably a grease.

Abstract: An improved crashworthy helicopter seat primarily for combat aircraft includes at least upper, intermediate and lower pairs of energy absorbers attached between the seat bucket and the frame of the aircraft and operable in both tension and compression. The energy absorbers comprise a plurality of telescoped tubes interfitted into one another and having coils of wire frictionally engaged between adjoining tubes such that energy is dissipated by motion of the tubes relative to one another through the plastic deformation of the coils of wire. The energy absorbers are adjustable to optimize safety parameters of occupants of the seat under a range of potential crash conditions including the most probable crash condition, for occupants having a substantial range of weight and size.

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 hydraulic seat cushioning device comprising a cylinder body and a piston has a concentric post-like upward projection in the cylinder body with a cylindrical surface in which there are a pressure fluid port and a vent port. An annular valving element closely slidably surrounding the post-like portion covers those ports when in a normal position but uncovers the vent port when above that position and uncovers the pressure fluid port when below it. The piston is so connected with the valving element as to move independently thereof in a lower portion of its stroke, but through the remainder of the piston stroke the valving element is constrained to move with the piston.

Abstract: A gas spring includes a cylinder receiving pressurized gas and liquid therein, a piston slidably disposed in the cylinder, a piston rod secured to the piston and extending to the outside of the cylinder through a first end thereof, a valve mechanism disposed in the cylinder for controlling movement of the fluid in the cylinder, thereby controlling movement of the piston in the cylinder, and a valve actuating element projecting to the outside of the cylinder through a second end thereof. The cylinder has a generally cylindrical portion extending from the second end thereof, and a valve operating member is pivotally supported on the extending portion of the cylinder.

Abstract: A device for adjusting the length of a gas spring is disclosed. This device includes an operating lever pivotally supported on a bracket rigid with the outer peripheral surface of the body proper of a gas spring. The operating lever has an outer end portion suited for operation, and an inner end portion inserted in the body proper of the gas spring. The device further includes a length-adjusting valve for the gas spring, which valve is actuated by the inner end portion of the operating lever, when the operating lever is operated by moving its outer end portion.

Abstract: The gas spring suspension comprises a gas-tight container capable of longitudinal expansion and contraction and on which the seat is supported, a valve system for connecting the container selectively to a compressed gas source or to exhaust to raise or lower the vehicle seat, a telescopically slidable coupling connected at one end to one end of the gas spring and including a detent which locks the slidable parts of the coupling together at a selected relative position corresponding to a selected vehicle seat height and a mechanical spring coupling connected between the other end of the slidable coupling and the other end of the gas spring, the spring coupling being expandible and contractable between end stops which thereby limit the resilient expansion and contraction of the gas spring, at any selected seat height, means for releasing the detent prior to operation of the valve system, and means fo automatically terminating the inlet of compressed gas into the gas spring in response to the slidable coupling b