Abstract: Self-pumping hydropneumatic spring strut includes a working cylinder divided into first and second working spaces by a working piston carried on a hollow piston rod; a high pressure chamber and a low pressure chamber partially filled with hydraulic damping medium, the high pressure chamber having a gas cushion and being connected to the second working space; and a piston pump including a pump rod extending into the hollow piston rod, the pump rod having a bore connected to the low pressure chamber, an end provided with a suction valve inside the hollow piston rod, and a deregulating opening, which is closable as a function of position of the working piston in the working cylinder. An adjustable damping valve located outside the external tube has a first flow connection connected to the first working space, and a second flow connection connected to the second working space and the high pressure chamber.

Abstract: Self-pumping hydropneumatic suspension strut unit with internal level control, with an oil-filled working cylinder subject to the pressure of gas cushions and with a damping piston, which is free to slide inside the cylinder and is mounted at the end of a hollow piston rod, the cavity of which serves as a pump cylinder for a pump rod attached to the working cylinder. Oil is drawn from a reservoir space when the piston rod travels outward, whereas the oil is conveyed into the working space when the piston rod travels inward. The pump rod passes through the end wall of the working space and is held axially in position by an end-mounted disk formed as a Belleville washer, which acts as a universal joint for the rod. The disk engages in a groove in the pump rod and is held in place by its outer circumference axially between the working cylinder and the end wall of the working cylinder.

Abstract: Methods and apparatus for accommodating vehicle suspensions that may bottom out. Some embodiments of the present invention include the secondary shock absorber placed within a primary shock absorber. Yet clear embodiments describe a shock absorber having multiple fluid flowpaths during compression, with one of the flowpaths being active near the bottoming-out condition.

Abstract: A self-pumping hydropneumatic spring strut unit includes a working cylinder filled with oil under pressure and a piston and rod unit displaceable in the cylinder so as to define two working spaces in the cylinder, and high-pressure and low pressure chambers surrounding the cylinder. The strut unit further has a piston pump operable to transport a working medium from the low-pressure chamber into the one working space which is in flow communication with the high-pressure chamber. The piston pump has a cylinder defined by the inner surface of the piston rod unit, and a hollow pump rod coupled to the working cylinder and having a flow channel in communication with the low-pressure chamber. The flow channel has a deregulating opening on the working space and a throttle in flow communication with the deregulating opening. A filter device protects the throttle from impurities carried by the oil during flow from the deregulating opening to the low pressure chamber.

Abstract: Spring strut unit for suspension systems of motor vehicles with a fastening connection on the body side and another fastening connection on the wheel side; with a helical spring supported between the body and the wheel; and with a vibration damper installed between the body-side fastening connection and the wheel-side fastening connection. The vibration damper includes a working cylinder, a damping piston attached to a piston rod, damping valves installed in the damping piston, and a compensating space. The helical spring can be pretensioned by a ring-shaped cylinder, which can be actuated by a hydraulic medium. A pump rod is mounted in a permanent axial position in the working cylinder of the vibration damper and cooperates with a cavity in the piston rod to form a pump space.

Abstract: A gas spring for suppression vibrations in payloads is provided. The gas spring comprises a piston disposed within the housing. The piston is configured to be displaced relative to the housing in response to vibrations applied to the housing. The piston has first concave or convex surface and a second surface opposing the first surface. The housing is configured to allow a first gaseous medium to apply a first gas pressure to the first concave piston surface, and a second gaseous medium to apply a second gas pressure to the second piston surface, thereby resulting in a net gas pressure force applied to the piston.

Abstract: The self-pumping hydropneumatic spring strut with an internal level control includes a cylinder having a high-pressure chamber and a low-pressure chamber, both chambers being at least partially filled with oil, the high-pressure chamber further comprising a gas cushion acting as a spring element. The spring strut also has an axially movable hollow piston rod arranged within the cylinder and carrying a working piston separating two working spaces arranged in the cylinder, one of the working spaces being connected to the high-pressure chamber, and a piston pump, which is driven by movements of the spring element, thus conveying oil from the low-pressure chamber to the working space connected to the high-pressure chamber. The piston pump includes a flow connection, which connects the high-pressure chamber to the low-pressure chamber.

Abstract: An oil-filled working cylinder is divided into first and second working spaces by a working piston, the first working space being connected to a high pressure chamber. A piston pump includes a pump rod received in a pump cylinder formed by the hollow piston rod, the pump rod having a bore connected to a low pressure chamber via a discharge valve, a distal end provided with a suction valve, and a down-regulating opening connecting the bore to the first working space as a function of the position of the working piston, the pump cylinder being connected to the first working space by an outlet valve. At least one of the valves is a check valve including a housing having a bore, a ball reciprocably guided in the bore by guide ribs, and a resilient retaining element capturing the ball in the bore and spring-loading the ball toward a valve seat.

Abstract: A gas-filled spring (1) operates using gas (13, 14) and may be intended for a motor cycle. The gas-filled spring comprises a cylinder (2) and a piston (4), said cylinder comprising a compression chamber and a return chamber (8, 9). An arrangement maintains the necessary quantities of gas and gas pressure settings or differential pressures in the chambers despite any gas leakage and temperature variations occurring. Arranged between the chambers is a passage (12), which is open only in a predetermined position of the cylinder and the piston relative to one another. In the open position gas transfer between the chambers and/or pressure equalization in or differential pressure adjustment of the gas pressures in the chambers are permitted. The invention also relates to a valve for counteracting rapid changes in leakage and temperature. The desired spring characteristic of the gas-filled spring can in this way be maintained despite leakage and temperature variations.

Abstract: The strut unit includes a piston dividing an oil-filled working cylinder into first and second working spaces, wherein the second working space is connected to a high pressure chamber having a gas cushion; a hollow piston rod defining a pump cylinder; and a pump rod received in pump cylinder. The pump rod has a bore extending between its ends, and a deregulating opening which connects the bore to the second working space when the piston rod is extended. A first check valve permits flow from the low pressure chamber into the bore; a second check valve permits flow from the bore into the pump cylinder; and a third check valve permits flow from the pump cylinder to the second working space. The check valves are formed as substantially identical modules having cylindrical valve housings which can be press fit into a recess in either of two orientations.

Abstract: A fluid-elastomeric damper assembly operable for damping relative motion between a first structure and a second structure including a housing structure grounded to the first structure and a plurality of elastomer seals coupled to the housing structure, the housing structure and the plurality of elastomer seals defining a fluid-elastomeric chamber operable for containing a fluid. The fluid-elastomeric damper assembly also including one or more piston structures disposed within the housing structure and the fluid-elastomeric chamber, the one or more piston structures grounded to the first structure and driven by the second structure, and the one or more piston structures each including a first fluid chamber and a second fluid chamber in communication via an orifice, the first substantially fluid-filled chamber and the second substantially fluid-filled chamber also in communication with the fluid-elastomeric chamber through a fluid backfiller.

Abstract: A height control valve for use in a vehicle suspension system for controlling the ride height of the trailer, the height control valve provided with a universal mounting for allowing greater flexibility in the mounting of the height control valve to a vehicle frame, the height control valve also having a position indicator to aide an installer in aligning a valve element contained within the valve according to a selected mounting position.

Abstract: A fluid-elastomeric damper assembly operable for damping relative motion between a first structure and a second structure including a housing structure grounded to the first structure and a plurality of elastomer seals coupled to the housing structure, the housing structure and the plurality of elastomer seals defining a fluid-elastomeric chamber operable for containing a fluid. The fluid-elastomeric damper assembly also including one or more piston structures disposed within the housing structure and the fluid-elastomeric chamber, the one or more piston structures grounded to the first structure and driven by the second structure, and the one or more piston structures each including a first substantially fluid-filled chamber and a second substantially-fluid-filled chamber in communication via an orifice, the first substantially fluid-filled chamber and the second substantially fluid-filled chamber also in communication with the fluid-elastomeric chamber.

Abstract: in particular for a motor vehicle, includes a high pressure chamber containing a gas cushion acting as a spring, and a working cylinder which is filled with damping medium under pressure of the gas cushion. A working piston carried by a hollow piston rod divides the working cylinder into two working spaces, wherein one of the working spaces is connected to the high pressure chamber to drive the piston under the pressure of the gas cushion, the piston having at least one non-return valve which permits flow from the one working space to the other working space.

Abstract: A suspension strut includes an outer tube having a first filling opening and a second filling opening, an intermediate wall received in the outer tube and separating a high pressure chamber from a low pressure chamber, a working cylinder located concentrically inside the outer tube in the high pressure chamber, and a gas filled separating envelope located between the working cylinder and the outer tube for pressurizing damping medium in the high pressure chamber. An axially displaceable piston divides the working cylinder into a first working space and a second working space, the first working space being connected to the high pressure chamber. A hollow piston rod passing through the second working space transports damping medium from the low pressure chamber to the first working space.

Abstract: A height control valve for controlling the relative height between a vehicle frame and a trailing arm suspension. The height control valve comprises a housing defining an interior chamber and having an inlet port fluidly connecting to a source of pressurized air. An air spring port is provided in the housing for fluidly connecting to an air spring. Additionally, an exhaust port is provided in the housing for fluidly connecting to the atmosphere. A valve is disposed within the interior chamber and is selectively operable between a fill position, an exhaust position, and a neutral position.

Abstract: Self-pumping hydropneumatic suspension strut with internal height control, in particular for motor vehicles with a work cylinder which is filled with oil and is under pressure by at least one gas cushion which is arranged in a high-pressure chamber and which acts as a spring, the work cylinder being divided into two work spaces by a work piston supported by a hollow piston rod, with a piston pump which is driven by the spring movements and conveys oil out of a low-pressure chamber into the work space connected to the high-pressure chamber and connects the work space connected to the high-pressure chamber to the low-pressure chamber by a regulating opening which is closable depending on the position of the work piston in the work cylinder, wherein a flow connection running through an intermediate wall and opening out below the surface of the oil is provided between the pump space and the low-pressure chamber, wherein the flow connection is arranged in the intermediate wall and has at least one bore hole in the

Abstract: A self-pumping, hydropneumatic suspension strut unit with an internal level control for a vehicle includes a low pressure chamber and a high pressure chamber for storing a damping medium under pressure. The high pressure chamber includes a gas cushion for displacing the damping medium therefrom when the damping medium is under less than a predetermined pressure. A working cylinder has a piston that defines a first volume of the working cylinder in fluid communication with the high pressure chamber. A piston rod is axially displaceable in inward and outward relative to the working cylinder. A pumping rod is axially mounted at one end in the working cylinder and a regulating bore is disposed at a first location of the pumping rod. The bore is closed when the first location is received in the piston rod and places the low pressure chamber in two-way fluid communication with the first volume when the regulating bore is open.

Abstract: A suspension damper comprises a cylinder tube and a control partition. The cylinder tube is disposed within a reservoir tube to define a fluid reservoir, and has at least one first hole. The control partition is disposed in the fluid reservoir, and communicates with the at least one hole.

Abstract: A fluid-elastomeric damper assembly operable for damping relative motion between a first structure and a second structure including a housing structure grounded to the first structure and a plurality of elastomer seals coupled to the housing structure, the housing structure and the plurality of elastomer seals defining a fluid-elastomeric chamber operable for containing a fluid. The fluid-elastomeric damper assembly also including one or more piston structures disposed within the housing structure and the fluid-elastomeric chamber, the one or more piston structures grounded to the first structure and driven by the second structure, and the one or more piston structures each including a first substantially fluid-filled chamber and a second substantially-fluid-filled chamber in communication via an orifice, the first substantially fluid-filled chamber and the second substantially fluid-filled chamber also in communication with the fluid-elastomeric chamber.

Abstract: Self-pumping hydropneumatic suspension strut with internal ride-height control, particularly for motor vehicles, with an outer tube with an oil-filled high-pressure work space under the pressure of at least one gas cushion acting as spring in a high-pressure chamber, a second work space on the piston rod side, and an axially displaceable piston which is supported by a hollow piston rod and is sealed in the work cylinder. The piston rod which is driven by the springing movement of the vehicle conveys oil from a low-pressure chamber to the second work space connected to the high-pressure chamber and a pump rod is received in a pump cylinder formed by the hollow piston rod.

Abstract: The invention relates to a vehicle spring apparatus comprising housing having fluid sealed therein. The housing comprises a cylinder with a slidably fitted piston and a piston rod connected at one end to said piston. The piston rod extends at the other end outside said cylinder and said cylinder is connected via a passage and a first valve to a first accumulator chamber comprising a springing medium. The cylinder is connected via a passage and a second valve to a second accumulator chamber comprising a springing medium, and said accumulator chambers is also connected with each other via at least one controllable pump. The invention also relates to a vehicle height adjusting system and a vehicle comprising the vehicle spring apparatus.

Abstract: A self-chargeable pneumatic cylinder comprises a cylinder body, a working piston disposed inside the cylinder body, and a hollow elongate shaft coupled to the working piston and extending outward from the cylinder body. The hollow interior of the shaft contains a pump mechanism for charging the pneumatic cylinder with a gas. The pump mechanism comprises a pumping piston that is axially slidable within the interior of the shaft and a pumping rod coupled to the pumping piston that is extendable out of the shaft for facilitating actuation of the pump. As the pump is manually actuated, pressurized gas flows into the cylinder body across a one-way valve to charge the pneumatic cylinder as desired.

Abstract: A suspension damper includes a reservoir housing with a piston slidably mounted therein and including a piston rod extending from the reservoir housing and attached to the vehicle by a mount assembly. An air chamber is defined by a sleeve cirucmscribing the piston rod and connected to the reservoir housing by a flexible portion. The mount assembly includes a pumping chamber which expands and contracts in response to normal road undulations to inflate the air chamber. A valve controlled by the flexible portion of the sleeve controls communication from the air chamber to ambient atmosphere to thereby control inflation of the air chamber and thereby controlling ride height.

Abstract: A self-pumping hydropneumatic spring strut with internal leveling for motor vehicles includes a working cylinder filled with damping medium. The working cylinder is under the pressure of at least one gas cushion arranged in a high-pressure chamber and acting as a spring. A piston divides the working cylinder into two working spaces and is connected to a hollow piston rod. Valves are arranged on the piston so that the two working spaces are in communiction through the valves. A piston pump is driven by the spring movements and pumps oil out of a low-pressure chamber into the working space connected to the high-pressure chamber and comprises a pump space formed by the hollow piston rod, a pump rod connected to the working cylinder. A further pressure generator acts upon the damping medium in the high-pressure chamber and/or the working space connected to the high-pressure space.

Abstract: A self-pumping hydropneumatic spring strut with internal leveling is provided for use in motor vehicles having an oil filled working cylinder, which is under the pressure of at least one gas cushion arranged in a high pressure chamber and acting as a spring. The high pressure chamber is connected to a working space, wherein a bleed opening forms a flow connection between the working space and the low pressure chamber. The bleed opening can be closed as a function of the position of the working piston in the working cylinder. The spring strut is assigned an actuator which displaces the spring strut in the vertical direction. The actuator can displace the motor vehicle to a plurality of displacement distances without requiring any electrical or electronic control, complex external leveling devices, or displacement detection systems.

Abstract: A self-chargeable pneumatic cylinder comprises a cylinder body, a working piston disposed inside the cylinder body, and a hollow elongate shaft coupled to the working piston and extending outward from the cylinder body. The hollow interior of the shaft contains a pump mechanism for charging the pneumatic cylinder with a gas. The pump mechanism comprises a pumping piston that is axially slidable within the interior of the shaft and a pumping rod coupled to the pumping piston that is extendable out of the shaft for facilitating actuation of the pump. As the pump is manually actuated, pressurized gas flows into the cylinder body across a one-way valve to charge the pneumatic cylinder as desired.

Abstract: A spring strut comprises a pneumatic spring and an oscillation damper and is fitted between a vehicle body and a wheel of a vehicle. The oscillation damper has a piston rod movable on an axis and a container concentric to the axis. The pneumatic spring has a spring chamber delimited by a rolling bellows which is firmly connected to the receptacle and to the container or a rolling-contact piston fixed to the container. An end wall that is in operative connection with the oscillation damper is acted upon on one side by the pressure in the spring chamber and has an effective area that extends obliquely to the axis of the oscillation damper and exerts a transverse force that is dependent on the pressure in the spring chamber and is perpendicular to the axis.

Abstract: A suspension unit for mounting an axle to the body of an automobile or a handle-bar to the fork of a bicycle or motorcycle. A pair of pistons (15, 29) operate in tandem in separate chambers (17, 31) having a compressible gas in spaces (21, 35) on one side of the piston and an uncompressible hydraulic fluid in spaces (19, 31) on the other side of the piston. One of the pistons (15) responds to external disturbances (caused by e.g. road bumps) to drive the other piston (29) against the compressible gas which responds resiliently to return the pistons to normal intermediate placements, thereby maintaining or recovering proper height of the automobile or′cycle parts. The hydraulic fluid spaces are communicated via constrictor passage to provide suitable dynamic dampening.

Abstract: A number of embodiments of suspension systems for vehicles having at least two wheels, each of which is independently suspended by a system including a respective shock absorber. The shock absorbers may be generally conventional in nature but are interconnected by a system that includes an accumulator and a flow control so as to provide a damping for vehicle characteristics that is independent of the individual damping of each wheel's shock absorber. The systems also provide constructions so that both the vehicle and individual wheel damping can be independently controlled to permit the use of smaller shock absorbers.

Abstract: A spring strut having a delayed bleed. The spring strut includes a non-return valve arranged parallel to the throttle such that the flow of oil can pass through the non-return valve from the low-pressure chamber in the direction of the pump cylinder.

Abstract: An apparatus and method for supporting a dynamic load relative to a foundation, such as a vehicle relative to the road, by a hydraulic system that monitors the movement of the load and adds or removes hydraulic fluid from the system to compensate for the load change. The hydraulic system is preferably one or more hydraulic cylinders that have a first chamber operably connected to the load and a second chamber operably connected to the foundation. The first and second chamber are connected by a valve. The valve is connected to the second chamber and a source of pressurized fluid with a reservoir. The first chamber senses the load change and the valve adds fluid from the pressurized fluid source to the second chamber or removes fluid from the second chamber to the reservoir to compensate for the change in the load and maintain the load in substantially the same position relative to the foundation.