Abstract: A control (60) that mounts in a space (52) between main vehicle parts (66, 68) that are supported one on the other by air bags (16). The control includes first and second vertical tubes (82, 106) that telescope in one another. The tubes enclose at least parts of valves (98, 111) and passages (84, 104, 101, 103) that connect the valves to inlet, exhaust and air bag ports (74, 76, 80).

Abstract: Suspension system for a vehicle, comprising two hydraulic piston-cylinder units (1) comprising a first and a second cylinder chamber (3a, 3b), connected with electro-hydraulic roll control means which are arranged to control the vehicle's roll behavior under electric control of the vehicle's computer system (C), comprising a direction valve, a pump unit and pressure control means. The direction valve is a hydraulically actuatable direction valve (6) having two first and two second switching ports (6a, 6b), interconnectable in three positions, and two hydraulic control ports (6c) which are either indirectly or directly, connected with said pump unit (5, 10). The pressure control means comprise an uni-directional pressure control module (9, 15), connected with both second switching ports of the hydraulically actuatable direction valve.

Abstract: Anti-roll system especially for a vehicle, comprising system control means, a tank (4) and a pump (3) for a hydraulic fluid, and two or more stabilizers, each stabilizer comprising an actuator (5, 6) which is arranged to control the relevant stabilizer's moment in dependency of the hydraulic pressure at the actuator's terminals. Each actuator has either one or both of its terminals (A, B) connected to a first terminal (I) of a pressure control module (8) which has a second terminal (II) connected to the tank's inlet side and a third terminal (III) to the pump's outlet side. The control means and each control module are arranged to supply a fluid pressure at its first terminal under control of said control means. The pressure control modules (8) may comprise a series connection of two pressure control valves (1, 2) e.g. pressure relief or limitation valves. As an alternative the pressure control modules (8) comprise a three-way pressure control valve (9), e.g. a three-way pressure reduction valve.

Abstract: A roll control system comprising a front torsion bar; a front first hydraulic actuator attached to the front torsion bar; a rear torsion bar; a rear first hydraulic actuator attached to the rear torsion bar; and control means connected to the hydraulic actuators and controlling the operation thereof on detection of a predetermined vehicle condition; wherein each hydraulic actuator comprises a first fluid chamber and a second fluid chamber; wherein the control means comprises a source of fluid pressure, a fluid reservoir, a pressure control valve fluidly connected between the pressure source and the reservoir, two pressure relief valves each having two positions to selectively fluidly connect the fluid chambers of the hydraulic actuators either to the pressure source or to the fluid reservoir, and a directional valve fluidly connected between the pressure relief valves and the fluid chambers of the hydraulic actuators; wherein the pressure relief valves and the directional valve are positioned on detection of

Abstract: An air suspension system includes a first transfer pipe having one end communicating with the outside, the first transfer pipe being constructed such that air flows through the first transfer pipe; a filter mounted adjacent to the one end of the first transfer pipe to filter out foreign matter from the air; a compressor mounted on the first transfer pipe, such that the compressor is located adjacent to the filter, to compress the air; a dryer mounted on the first transfer pipe, such that the dryer is located adjacent to the compressor, to dry the air; an exhaust pipe extending from the first transfer pipe between the compressor and the dryer; an exhaust valve mounted on the exhaust pipe to control the flow of the air; a second transfer pipe communicating with the other end of the first transfer pipe; a control unit connected to the second transfer pipe, the control unit being constructed such that the high and low of the control unit are controlled by the pressure of the air; and a storage unit connected to t

Abstract: An air suspension device includes a housing enclosing a compressor chamber that communicates with an air source and at least one piston chamber, optionally through internal air ports. A compressor is disposed in the compressor chamber. When the compressor is driven by a power source, such as a motor, the compressor draws air from the air source and drives the air into the piston chamber. A piston disposed in the piston chamber is cushioned by the pressurized air.

Abstract: A pneumatic proportioning system for heavy-duty vehicle air springs includes an air supply, a height control valve and a solenoid valve in fluid communication with one another and with the air springs of at least one axle/suspension systems of a heavy-duty vehicle. A proportioning means is in fluid communication with the air supply, with the height control valve, with the solenoid valve, with the air springs and with atmosphere and operates to proportion loads between the air springs of the axle/suspension systems when the solenoid valve is activated during operation of the heavy-duty vehicle.

Abstract: A valve is disclosed for use in a system and process for controlling vehicle loading on a multi-axle vehicle and improving maneuverability. The valve partially exhausts air from an axle air bag when the vehicle is maneuvering at slow speed, reduces the load on the axle, and thus reduces damaging forces that affect tire wear and suspension component wear. The valve is a normally open, pilot operated valve that delivers supply air pressure upon receiving a sustained air pressure input of a pilot signal. Using an inversion function, the valve then dumps the delivery pressure through a high capacity exhaust upon receiving the pressure input of a secondary control signal. The hold function of the valve traps a reduced amount of delivery air pressure by closing the exhaust valve, and the hold function is actuated at a predetermined delivery pressure to trap a volume of air in the associated air suspension system until the valve member is returned to a supply position.

Abstract: A hydraulic system for a vehicle suspension for a vehicle, the vehicle including a vehicle body and at least two forward and two rearward wheel assemblies, the vehicle suspension including front and rear resilient vehicle support means between the vehicle body and the wheel assemblies for resiliently supporting the vehicle above the wheel assemblies, the hydraulic system including: at least two front (11, 12) and two rear (13, 14) wheel rams respectively located between the wheel assemblies and the vehicle body, each ram (11 to 14) including at least a compression chamber (45 to 48) and a rebound chamber (49 to 52); wherein the compression chamber (45, 46) and rebound chamber (49, 50) of each said front wheel ram (11, 12) is in fluid communication with the rebound chamber (47, 48) and compression chamber (51, 52) respectively of a diagonally opposed said rear wheel ram (13, 14) to respectively provide two fluid circuits, each fluid circuit providing a front and back compression volume therein, the front compr

Abstract: An active, independent suspension system has dual piston, compressible fluid struts (22). Each of the dual piston struts (22) has an outer cylinder (24) and an outer piston rod (30), which each respectively define exterior peripheries for an outer pressure chamber (32) and an inner pressure chamber (54). Pressures applied to a compressible fluid (56) in respective ones of the outer and inner pressure chambers (32, 54) urge the outer piston to extend from within the outer cylinder (24). A control system (240) is provided for actively controlling an amount of compressible fluid (56) disposed within each of the outer and inner chambers (32, 54).

Abstract: A method and apparatus for a low-profile suspension system, which provides coarse and fine suspension control to an object supported by the low-profile suspension system. Coarse suspension is provided to adaptively control a position of the object through pneumatic support devices. Pneumatic pressure is adaptively increased in the pneumatic support devices to support an increasing weight of the object, while pneumatic pressure is adaptively decreased in the pneumatic support devices to support a decreasing weight of the object. Fine suspension control is provided through rotational actuation of a shock absorbing device through a right-angle gear drive. By rotationally actuating the shock absorbing device, a range of stroke of the shock absorbing device along a vertical direction is minimized. Position equalization control is further provided to maintain a position of the object along an axis that is orthogonal to the coarse and fine suspension axis.

Abstract: An air suspension system for a multi-axle vehicle has an air bag system including at least one air bag operatively associated with the vehicle wheels on selected wheel and axle sets to control relative movement between each of the selected wheels and a supporting frame structure of the vehicle. The system has an air-flow control arrangement to control the flow of air into each air bag to thereby control the relative movement of the wheels and vehicle frame structure. A pressurizing arrangement is provided to maintain a selected, predetermined pressure in the air bag system when the vehicle is at rest to thereby maintain a desired vehicle height. The pressurizing arrangement includes a valve to admit pressurized air to or exhaust air from the air bag system to maintain the predetermined vehicle height. The valve is actuated by a link associated with a rocker member connected to spaced axles of the vehicle.

Abstract: A hydraulic control circuit (100) comprises a source (180) of fluid pressure having a fluid inlet (201) and a fluid outlet (202); a fluid reservoir (181) fluidly connected to the fluid inlet of the pressure source; an attenuation means (111) having a fluid inlet (203) fluidly connected to the fluid outlet of the pressure source, and a fluid outlet (204); a pressure control valve (199) fluidly connected to the fluid inlet of the attenuation means and to the fluid reservoir or the fluid inlet of the pressure source; and one or more valves (82-84) fluidly connected to the fluid outlet of the attenuation means.

Abstract: An integrated trailer suspension damper assembly for a trailer or towed vehicle that includes a trailer suspension damper, an air spring concentrically attached to an upper portion of the trailer suspension damper with an end rotatably attached to a trailer frame, a yoke having an upper end fixedly attached to a lower portion of the trailer suspension damper and a lower end constructed to be rotatably attached to a lower wishbone control arm, and a controller for controlling the trailer suspension damper assembly. The integrated trailer air spring damper assembly is constructed to maintain a uniform spring rate of said integrated suspension damper assembly to provide a lateral roll stability.

Abstract: An integrated suspension damper assembly for a drive vehicle and a trailer fleet combination includes a suspension damper, an air spring concentrically attached to an upper portion of the suspension damper with an end rotatably attached to a vehicle frame, a yoke having an upper end fixedly attached to a lower portion of the suspension damper and a lower end constructed to be rotatably attached to a lower wishbone control arm. The integrated air spring damper assembly is constructed to maintain a uniform spring rate of said integrated suspension damper assembly to provide a lateral roll stability. Components of said integrated suspension damper assembly are interchangeable for use with the integrated suspension damper assembly as installed in the drive vehicle and its trailer.

Abstract: An integrated trailer suspension damper assembly for a trailer or towed vehicle that includes an integrated trailer air spring damper assembly. The integrated trailer air spring damper assembly includes a trailer suspension damper, an air spring concentrically attached to an upper portion of the trailer suspension damper with an end rotatably attached to a trailer frame, a yoke having an upper end fixedly attached to a lower portion of the trailer suspension damper and a lower end constructed to be rotatably attached to a lower wishbone control arm. The integrated trailer air spring damper assembly is constructed to travel a maximum linear articulation distance.

Abstract: A vehicle roll control system for a vehicle having a pair of front wheels and a pair of rear wheels each rotatable on an axle, comprising a front hydraulic actuator attached to the front torsion bar; a rear hydraulic actuator attached to the rear torsion bar; and control means connected to the front and rear hydraulic actuators and controlling the operation thereof on detection of a predetermined vehicle condition; wherein each front and rear hydraulic actuator comprises a housing, a piston making a sealing sliding fit inside the housing to define a first fluid chamber and a second fluid chamber, and a piston rod connected to the piston and extending through the second fluid chamber and out of the housing; wherein the control means acts on detection of the predetermined vehicle condition to apply a fluid pressure to the first fluid chambers of the front and rear hydraulic actuators and to apply a fluid pressure to the second fluid chambers of the front and rear hydraulic actuators; and wherein the control mea

Abstract: An air suspension system for a load carrying vehicle has multiple air bags associated with selected vehicle wheels to at least assist supporting the load and to control relative movement between the respective wheel and a supporting frame structure of the vehicle. A high flow-rate air tube connected to at least one air bag receives air from the connected air bag when air pressure in the air bag increases above that in the air tube. Air flows from the high flow rate air tube to a connected air bag when the air pressure in the air tube is above that of the air bag. The flow rate of air from the air tube to the air bag is controlled by the structure of the fittings between the respective air bags and the high flow-rate air tubes. A height valve maintains a predetermined pressure in the air bags when the vehicle is at rest.

Abstract: A wheel suspension includes a working cylinder, a main spring in parallel with the working cylinder, and a piston rod extending from the working cylinder and having a longitudinal axis, the piston rod having fixed thereto a piston and a mount for fixing the piston rod against movement with respect to a vehicle body. The piston is mounted with freedom of axial movement in an adjusting cylinder, the piston dividing the cylinder into a space above the piston and a space below the piston, and an additional spring is located on the longitudinal axis for supporting the adjusting cylinder against the working cylinder. A shut-off element is located in a flow connection connecting the space above the piston to the space below the piston, whereby movement of the piston in the adjusting cylinder can be blocked when the vehicle rolls.

Abstract: A composite suspension system for a vehicle includes a mechanical suspension system supporting the body of the vehicle with respect to an axle and a pneumatic suspension system to selectively provide support for the body relative to the axle. Under heavy loads, the pneumatic suspension system may be inflated to support the body relative to the axle. When not under heavy loads the pneumatic suspension system may be deflated so as not to interfere with the support provided by the mechanical suspension system. A control system regulates a compressor connected to the pneumatic suspension system to inflate the same. The control system also regulates access of the pneumatic suspension system to a vacuum source to deflate the same.

Abstract: An arrangement for a suspension for a load carrying vehicle is provided. The suspension is provided with air springs and comprises at least one front axle and at least two rear axles, and each rear axle is provided with at least one pair of corresponding suspension air springs and at least one air spring is provided for lifting one of the rear axles. The suspension air springs for at least the rearmost axle is connected to the air spring for lifting one of the rear axles by a conduit for compressed air, which conduit is provided with a controllable valve, whereby the controllable valve is arranged to open during a vehicle loading process. A vehicle provided with the arrangement, and a method for carrying out a loading operation using the arrangement, are also described.

Abstract: A hydraulic system incorporated into a vehicle is provided. The system includes a plurality of actuators for providing a desired configuration of a vehicle. A valve system is operatively coupled to the plurality of actuators for controlling a flow of pressurized fluid to the plurality of actuators to energize the actuators to produce, responsive to the desired configuration of the vehicle, a first configuration of a plurality of first configurations of the vehicle corresponding to the desired configuration of the vehicle, or a second configuration of a plurality of second configurations of the vehicle corresponding to the desired configuration of the vehicle.

Abstract: Complementary suspension device applicable between the hydro-pneumatic suspension systems of at least two wheels of a vehicle, which transfer the forces originating in said wheels to the aforementioned complementary device by means of displacement, and/or decanting, of the fluids of said suspension systems through the corresponding conduits, said device comprising two fluid distribution units connected in parallel by means of each joint conduit, between the hydro-pneumatic suspension systems of at least one pair of vehicle wheels, in such a way that for each pair of wheels the first distribution unit is capable of allowing the intake of fluid through the joint conduit with the suspension system of one of the wheels and, at the same time, lets fluid exit through the joint conduit with the suspension system of the other wheel, whereas the second unit only allows the intake of fluid through the joint conduits with the two suspension systems at the same time.

Abstract: A suspension system adaptable for cross-flow operation includes a plurality of gas springs, a transfer passage in communication between the gas springs, and a transfer valve for selectively permitting gas flow along the transfer passage. A control system selectively actuates the transfer valve. A method of operation is also described.

Abstract: In order to start vehicle height adjustment control even when an air suspension air tank is empty or sufficient air is not left therein, a vehicle height adjustment system includes a compressor which produces compressed air, a magnetic valve which controls air supply and discharge to/from air springs, a control unit which controls a valve opening/closing operation of the magnetic valve, an air passage which connects between the compressor and the magnetic valve through a main air tank bypassing the air suspension air tank, and an air suspension control pressure switch which detects an internal pressure value of the air passage. The control unit controls start and stop of air supply, namely, start and stop of vehicle height adjustment control at the magnetic valve, based on the internal pressure value detected by the air suspension control pressure switch.

Abstract: A damper system is connected between pivotal components of a vehicle suspension system to inhibit movement of the components during a condition of potential vehicle roll. The system can be actively or passively controlled. The damper system can have a single damper or multiple dampers and may be connected to work in conjunction with vehicle stabilizers including torsion bars, single compensator stabilizing systems and dual compensator stabilizing systems. In the compensator stabilizing systems, the damper can be separate from the compensators or integral with the compensators. The dampers also can be formed as integral structures with shock absorbers. The dampers can be of various types, including but not limited to linear dampers and rotary dampers.

Abstract: A height control valve for an air spring of an air-ride axle/suspension system of a heavy-duty vehicle includes a body. The valve body is pneumatically connected to an air reservoir of the vehicles an ail spring, and to atmosphere A control arm actuates the valve to direct air from the reservoir into the air spring, when air is to be added to the air spring When air is to be exhausted from the air spring, the valve, actuated by the control arm, directs air from the air spring to atmosphere The valve includes a throttle assembly that can regulate the rate of pneumatic flow from the air spring to atmosphere when the vehicle is loaded and the air spring is in an extended condition. A throttle assembly can also be used to regulate the rate of pneumatic flow from the air reservoir to the air spring.

Abstract: An active chassis system of a motor vehicle having two axles with two wheels each. Each wheel is supported via a spring element and a hydraulic piston-cylinder unit acting as a damper and as a hydraulic actuator for introducing additional force between the wheel and the body. Each of the working chambers of the actuator is supplied with hydraulic pressure from a delivery pump. The working chambers of actuators of an axle having smaller cross-sectional area are connected directly to one another, and a directional valve is used for roll control. The directional valve is a pilot-operated directional valve whose control pressure is tapped in parallel with a controllable throttle. The throttle is connected between the working chambers having larger cross-sectional area of the axle's two actuators, and adjusts the pressure drop between the working chambers, depending on the direction of rotation and/or the output of the delivery pump.

Abstract: A vehicle height adjusting apparatus includes air spring portion, an air supply source, a switching valve causing a total air volume of the air spring portion to be constituted by only a main air chamber and by a sum of the main air chamber and a sub air chamber, an auxiliary valve, operating state determining portion for determining an operating state of the vehicle, and controlling portion for controlling the adjusting valve, the switching valve and the auxiliary valve.

Abstract: Air-demand-controlled compressor arrangement, particularly for commercial vehicles, includes a motor unit for generating a rotating movement which, by way of an interposed rotational-speed-transmitting transmission unit, drives a compressor unit for generating compressed air from ambient air. A control unit triggers the generating of compressed air in the case of a compressed-air demand. The transmission unit is constructed in the manner of a transmission whose rotational speed can be varied, and the control unit interacts with the transmission unit in order to adapt the rotational speed of the transmission unit corresponding to the compressed-air demand.

Abstract: An air-suspension system for vehicles, in particular for commercial vehicles, including at least one air-bellows valve assigned to an air-spring bellows or a group of air-spring bellows of the front axle for individually aerating and venting this air-spring bellows or this group of air-spring bellows; at least one air-bellows valve assigned to an air-spring bellows or a group of air-spring bellows of the rear axle for individually aerating and venting this air-spring bellows or this group of air-spring bellows; as well as at least one central aeration valve for supplying the air-bellows valves assigned to the air-spring bellows of the front axle and the rear axle with compressed air from a compressed-air supply; and at least one central venting valve for exhausting compressed air from the air-bellows valves assigned to the air-spring bellows of the front axle and the rear axle, to an air vent.

Abstract: A vehicle subassembly includes first and second hydraulic cylinders each having an upper chamber and a lower chamber. A fluid circuit is hydraulically connected to the first and second hydraulic cylinders and includes a valve movable between a first position where the upper chamber of the first hydraulic cylinder and the lower chamber of the second hydraulic cylinder are hydraulically connected and the lower chamber of the first hydraulic cylinder and the upper chamber of the second cylinder are hydraulically connected, and a second position where the upper chamber and the lower chamber of the first hydraulic cylinder are hydraulically connected and the upper chamber and lower chamber of the second hydraulic cylinder are hydraulically connected. A control unit is operable to position the valve in at least one of the first position and the second position based on an operating variable of the vehicle.

Abstract: A vehicle air-suspension system, especially an air-suspension system designed as a partly closed system, and a method for operating the system are provided. The air-suspension system includes at least one compressed-air delivery device, a plurality of air-suspension bellows and valves constructed and arranged for control of the filling of one, several or all air-suspension bellows with compressed air discharged by the compressed-air delivery device. The method avoids an undesirably large pressure rise on the pressure-outlet side of the compressed-air delivery device as the effective delivery capacity of the compressed-air delivery device is automatically controlled as a function of the state defined by the arrangement of the valves.

Abstract: Apparatus for the active stabilization of the rolling of a vehicle that has at least two axles that each have at least two wheels. The axles are each equipped with a transverse stabilizer that is hydraulically actuated by a directional control valve. The transverse stabilizers are operated by respective hydraulic motors. A pressure supply pump applies different hydraulic pressure levels through respective pressure limiting valves. The directional control valve is actuated hydraulically by a directly controlled control valve.

Abstract: An air suspension system for a load bearing vehicle which includes a pair of air springs fluidly connected to a pair of auxiliary air reservoirs and to a main air reservoir. The system includes control valves which permit the air in the air springs to be exhausted therefrom to lower the vehicle frame without exhausting the air from the auxiliary air reservoirs.

Abstract: Anti-roll system especially for a vehicle, comprising system control means, a tank (4) and a pump (3) for a hydraulic fluid, and two or more stabilizers, each stabilizer comprising an actuator (5, 6) which is arranged to control the relevant stabilizer's moment in dependency of the hydraulic pressure at the actuator's terminals. Each actuator has either one or both of its terminals (A, B) connected to a first terminal (I) of a pressure control module (8) which has a second terminal (II) connected to the tank's inlet side and a third terminal (III) to the pump's outlet side. The control means and each control module are arranged to supply a fluid pressure at its first terminal under control of said control means. The pressure control modules (8) may comprise a series connection of two pressure control valves (1, 2) e.g. pressure relief or limitation valves. As an alternative the pressure control modules (8) comprise a three-way pressure control valve (9), e.g. a three-way pressure reduction valve.

Abstract: A valve is disclosed for use in a system and process for controlling vehicle loading on a multi-axle vehicle and improving maneuverability. The valve partially exhausts air from an axle air bag when the vehicle is maneuvering at slow speed, reduces the load on the axle, and thus reduces damaging forces that affect tire wear and suspension component wear. The valve is a normally open, pilot operated valve that delivers supply air pressure upon receiving a sustained air pressure input of a pilot signal. Using an inversion function, the valve then dumps the delivery pressure through a high capacity exhaust upon receiving the pressure input of a secondary control signal. The hold function of the valve traps a reduced amount of delivery air pressure by closing the exhaust valve, and the hold function is actuated at a predetermined delivery pressure to trap a volume of air in the associated air suspension system until the valve member is returned to a supply position.

Abstract: Disclosed is a pneumatic shock absorbing system (1) for a motor vehicle, comprising at least one pneumatic spring (18a, 18b, 18c, 18d) per motor vehicle wheel on at least one vehicle axle, at least one control device (36), at least one compressor (2), at least one pressure sensor (10), at least one on-off valve (20a, 20b, 20c, 20d), and at least one connecting pipe (8, 16a, 16b, 16c, 16d, 62, 64) which is connected to an external source (76) of compressed air. The control device (36) of the pneumatic shock absorbing system (1) receives a start signal for basic filling while at least one valve (20a, 20b, 20c, 20d) is triggered by the control device (36) in such a way that at least one component (8, 16a, 16b, 16c, 16d, 18a, 18b, 18c, 18d, 62, 64) of the pneumatic shock absorbing system (1) is basically filled.

Abstract: A pneumatic proportioning system for heavy-duty vehicle air springs includes an air supply, a height control valve and a solenoid valve in fluid communication with one another and with the air springs of at least one axle/suspension systems of a heavy-duty vehicle. A proportioning means is in fluid communication with the air supply, with the height control valve, with the solenoid valve, with the air springs and with atmosphere and operates to proportion loads between the air springs of the axle/suspension systems when the solenoid valve is activated during operation of the heavy-duty vehicle.

Abstract: A pneumatic suspension system for a vehicle includes pneumatic bellows connectable by means of a valve arrangement to at least one other component of the pneumatic suspension system in order to selectively increase or decrease the amount of compressed air therein. The other component contains at least one volume. Undesirable changes in the amount of compressed air inside the pneumatic bellows arising as a result of pressure compensation are avoided or reduced to a non-disruptive level by a return valve between the valve arrangement and the volume which prevents compressed air from flowing between the pneumatic bellows and the volume in one direction of flow.

Abstract: A roll control system comprising a front torsion bar; a front first hydraulic actuator; a front second hydraulic actuator; a rear torsion bar; a rear first hydraulic actuator; a rear second hydraulic actuator; and control means connected to the hydraulic actuators and controlling the operation thereof on detection of a predetermined vehicle condition; wherein each hydraulic actuator comprises a first fluid chamber and a second fluid chamber; wherein the control means comprises a source of fluid pressure, a fluid reservoir, a pressure control valve fluidly connected between the pressure source and the reservoir, and at least three pressure relief valves each having two positions to fluidly connect the fluid chambers of the hydraulic actuators either to the pressure source or to the fluid reservoir; wherein the pressure relief valves are positioned on detection of the predetermined vehicle condition to apply a fluid pressure to the first fluid chamber of the first front hydraulic actuator and to the second flui

Abstract: A hydraulic system for use in a motorized vehicle including a pressure source, a valve fluidly coupled to the pressure source, and an actuator fluidly coupled to the valve. The actuator includes an outer casing and a piston slidably received in the outer casing such that the piston defines a piston chamber and a rod chamber in the outer casing. The actuator includes a rod coupled to the piston on a side of the piston facing the rod chamber. The valve is configured such that when the valve is in an open position the valve provides fluid communication to the rod chamber and provides fluid communication to the piston chamber. Fluid flowing through the valve to the rod chamber passes through a restricted orifice having cross sectional area that is smaller than the cross sectional area of any orifice that would be passed through by fluid flowing through the valve to the piston chamber.

Abstract: The present invention relates to a wheelchair suspension that includes a pivoting assembly. The pivoting assembly includes at least two linkages. The pivoting assembly is structured so that the drive assists the wheelchair in traversing obstacles.

Abstract: In one embodiment, a gas spring having a travel control includes positive and negative chambers and a valve mechanism that controls the fluid communication between the chambers. The valve mechanism includes a valve bore that while only moving a small amount, allows for large changes in gas spring travel length.

Abstract: A vehicle hydraulic suspension system has front left (15), front right (16), rear left (18) and rear right (17) wheel ram. There is a mode decoupling device (100) with first (129), second (130), third (132) and fourth (131) balance chambers formed by a cylinder/piston rod assembly (124,125,126). The compression chamber (45) of the front left wheel ram (15) is in fluid communication with the first balance chamber (129), the compression chamber (46) of the front right wheel ram (16) is in fluid communication with the second balance chamber (130), the compression chamber (48) of the rear left wheel ram (18) is in fluid communication with the third balance chamber (132), and the compression chamber (47) of the rear right wheel ram (17) is in fluid communication with the fourth balance chamber (131). There are also front and rear resilient vehicle support means between vehicle body and the wheel assemblies.

Abstract: A lift system for integration with the air suspension system of a truck for raising the rear of the truck so that the trailer can be attached and the landing gear let up includes an air dump valve, two air control switch valves, one one-way valve, one air gauge rated to 100 psi., one air regulator, an on/off control switch, a safety alarm buzzer, and the appropriate number and size of fittings and airlines. The on/off control switch is located within the cab of the truck and allows the operator to manually engage or disengage the lift system. The lift system is interconnected to and powered by the truck's main battery and main air supply whereupon engagement of the lift system facilitates the alignment and connection of the rear of the truck to the trailer and removes the weight from the truck's landing gear by raising the landing gear so that the landing gear can be let up.

Abstract: A pneumatic suspension system for a vehicle includes a compressed air accumulator, a compressed air transport device, at least one pneumatic bellows and an electrically controllable reversing valve used to connect the compressed air accumulator to a suction connection of the compressed air transport device, in order to increase the amount of air in the pneumatic bellows in a first switching position, and to connect an outlet connection of the compressed air transport device to the pneumatic bellows, also used to connect the pneumatic bellows to the suction connection of the compressed air transport device and the outlet connection of the compressed air transport device to the pressure accumulator in a second switching position in order to reduce the amount of air in the pneumatic bellows. The reversing valve can be pre-controlled with the compressed air of the pneumatic suspension system.

Abstract: An air suspension system for a load bearing vehicle which includes a pair of air springs fluidly connected to a pair of auxiliary air reservoirs and to a main air reservoir. The system includes control valves which permit the air in the air springs to be exhausted therefrom to lower the vehicle frame without exhausting the air from the auxiliary air reservoirs.

Abstract: A ride control suspension control system having suspension control units with a damper and a single pressure regulator that controls dampening in both the compression and rebound chambers of the damper. The fluid control circuit may include a plurality of check valves that coordinate the flow of fluid to and from both chambers through the pressure regulator. In one embodiment, the system includes a central controller that receives input from a variety of sensors and directly controls operation the pressure regulators in each of the suspension control units without the need for any remote processors. The ride control suspension system may also include wheel position sensors that are external to the accumulator.

Abstract: The present invention relates to a solenoid valve configured to be mounted to a shock absorber of a vehicle to adjust damping force. solenoid valve of a shock absorber in which a damping force is adjusted through adjustment of back pressure against a disc valve. The solenoid valve includes a back pressure chamber for generating back pressure against the disc valve by a fluid introduced through a back pressure adjusting flow passage, and a spool moved in a spool guide by operation of a solenoid to control opening/closing or opening rate of the back pressure adjusting flow passage. The back pressure adjusting flow passage includes a variable orifice with an opening rate of the variable orifice being adjusted by the spool and the spool guide, the back pressure chamber, and a fixed orifice formed on the disc valve.