Abstract: An air-suspension device for vehicles, e.g., commercial vehicles, includes a valve block that is assigned to a rear axle and contains a central valve for aerating and venting air-spring bellows of the rear axle, and a valve block assigned to a front axle for aerating and venting air-spring bellows of the front axle. The central valve of the valve block assigned to the rear axle selectively connects: a) a compressed-air supply to the air-spring bellows of the rear axle and to a supply-pressure connection of the valve block assigned to the front axle; or b) the supply-pressure connection of the valve block assigned to the front axle and the air-spring bellows of the rear axle to an air vent. The valve block assigned to the front axle has a pneumatic pilot-operation connection for pneumatic-electric pilot operation.

Abstract: A hydraulic pressure control apparatus for stabilizers controls hydraulic fluid in a hydraulic communication path hydraulically connecting cylinders each operatively connected to each stabilizer of a vehicle. The apparatus includes a spool valve provided in the hydraulic communication path. The spool valve includes a housing, a spool accommodated in the housing, first and second spool chambers defined by the spool and the housing, and a biasing member for biasing the spool.

Abstract: A vehicle suspension system that includes a cylinder, a rod inserted within the cylinder, a piston coupled to the rod and a piston valve which has an input piston current. The suspension system further includes a base coupled to the cylinder, a base valve which has an input base current, and a controller coupled to the piston valve and the base valve. The controller is adapted to generate the input piston current and the input base current based on a generated virtual current.

Abstract: A suspension system for an agricultural or construction industry vehicle is described. The suspension system comprises two hydraulic cylinders, which support a frame in relation to an axle of the vehicle, the hydraulic cylinders each having a piston-side chamber and a piston rod-side chamber and each of the chambers of the hydraulic cylinders being connectable to one another via connecting lines provided with a switch valve, a first supply line, which can be connected via a switch valve to the piston-side connecting line of the first hydraulic cylinder, a second supply line, which can be connected via a switch valve to the piston-side connecting line of the second hydraulic cylinder, a hydraulic accumulator, in each case connectable to the supply lines via proportionally adjustable orifices, a hydraulic source, a hydraulic tank, a control valve device, and an electronic control unit.

Abstract: A vehicle suspension system for a vehicle, including: (a) a plurality of suspension cylinders each disposed between a chassis-side member and a corresponding one of a plurality of wheel-side members; (b) a controller cylinder including a housing and at least one piston slidably mounted in the housing, such that the housing and the at least one piston cooperate to define a plurality of chambers each having a volume that is variable upon slide movement of the at least one piston relative to the housing; (c) individual conduits each communicating a corresponding one of the plurality of chambers of the controller cylinder and a chamber of a corresponding one of the plurality of suspension cylinders; and (d) a suspension-cylinder operation facilitator operable to facilitate an operation of each of the plurality of suspension cylinders for permitting displacement of each of the plurality of wheel-side members relative to the chassis-side member after the at least one piston of the controller cylinder has reached it

Abstract: A hydropneumatic suspension having at least one suspension cylinder (10) and at least one hydraulic accumulator configured as a suspension accumulator (18) has a pilot-actuated valve (20) for opening or blocking a fluid-carrying connection between the suspension cylinder (10) and the suspension accumulator (18). The pilot-actuated valve (20) can be moved into the blocked position by a hydraulic actuating assembly (22). The hydraulic actuating assembly (22) taps the fluid pressure between suspension accumulator (18) and the suspension cylinder (10), and forwards it by a switching valve (24) to an operating side (26) of the pilot-actuated valve (20) through a pilot-actuated line (38). Another proportional valve (50), or such valve connected to the respective associated pilot-actuated line (38), can be between one switching valve (24) and the pilot-actuated valve (20).

Abstract: The invention relates to a method for controlling air flow in a level control system for a motor vehicle. Two air flow intervals are indicated for controlling air flow. The first air flow interval I1 is located entirely within air flow interval I2. If the air flow in the level control system is located outside air flow interval I2, an automatic adjustment is made in air flow interval I2. If the air flow is still located outside air flow interval I1 and within second air flow interval I2, the air flow is adjusted to the first air flow interval I1 exclusively when the motor vehicle is in operation.

Abstract: The invention relates to a vehicle air suspension system and an air suspension unit (10) therefor. The air suspension system comprises a plurality of suspension elements, wherein each element includes at least one air suspension unit (10). The air suspension unit (10) consists of an integrated assembly mountable between the chassis and the axle of a vehicle, and includes: an air spring (14); a height sensor (33) for providing a tide height signal; a valve (32); and an electronic controller (36). The electronic controller (36) controls the valve (32) to adjust a volume of air in the air spring (14) in response to the ride height signal from the height sensor (33).

Abstract: A compressed air processing apparatus includes a pressure controller, an air dryer, a multi-circuit protection valve and an electronic control unit. A switching valve is designed and arranged to supply compressed air to an air suspension system and to deaerate the air suspension system. The electronic control unit is designed and arranged to control the pressure controller, the air dryer and the multi-circuit protection valve. The electronic control unit is designed and arranged to also control the switching valve of the air suspension system.

Abstract: An active roll stabilization system of a vehicle having an axle with at least two wheels, wherein the axle is provided with a roll stabilizer that is actuated by means of a hydraulic device. The hydraulic device is actuated and controlled by at least one pressure control valve with a preselected pressure level by a pressure supply device, such as a pump. In order to reduce the costs for producing such an active roll stabilization system, the pressure control valve is pilot-operated by a pressure control pilot valve.

Abstract: A skid steer vehicle has a chassis with four drive wheels suspended from the chassis that are damped by four damping cylinders. An electronic controller varies the damping of the cylinders in an automatic mode, based on certain operational parameters of the vehicle, and in a manual mode in response to operator selection of a desired degree of suspension damping.

Abstract: A vehicular suspension system having a fluid circuit including two fluid cylinders provided on respective front-wheel and rear-wheel sides, and two fluid passage systems one of which connects one of two fluid chambers of the fluid cylinder on the front-wheel side to the corresponding one of the two fluid chambers of the fluid cylinder on the rear-wheel side, and the other of which connects the other fluid chamber of the front-wheel side fluid cylinder to the other fluid chamber of the rear-wheel side fluid cylinder, the suspension system including a diagnosing device operable to diagnose the fluid circuit for any abnormality, on the basis of at least one of fluid pressures in the two fluid passage systems.

Abstract: A sensor for a height control system uses a transducer to detect changes in position of an arm relative to a vehicle and sends a proportional signal to a microprocessor that, in turn, actuates a pneumatic valve operably connected to an air spring between the arm and the vehicle. The transducer includes an optical bridge, a variable capacitor, or a flexible variable resistor.

Abstract: A height control valve linkage assembly for an air suspension system, including an air bag and a height control valve controlling the supply of air to the air bag. A telescopic linkage is positioned between the arm of the height control valve and the suspension. The linkage is extended to alter the ride height setting of the height control valve, thereby selectively providing additional clearance.

Abstract: A vehicle roll control system for a vehicle has a hydraulic actuator attached to a torsion bar. The system includes first and second pressure control valves fluidly connected in series between a pressure source and a reservoir, and a directional valve fluidly connected between the pressure control valves and the hydraulic actuator. The control valves are actuated to control the fluid pressure within the hydraulic actuator to either extend or compress the hydraulic actuator based on the detection of a predetermined vehicle condition for controlling vehicle roll.

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: An air suspension system includes an air tank, an air drier, a compressor, and an air spring, which are sequentially provided in a first line. The air suspension system further includes a second line, a third line, an intake line, and a discharge line, which are connected to the first line. The first line, the second line and the third lines can be switched by a 4-port/2-position solenoid valve, and the first line is selectively connected to the intake line by a 3-port/2-position solenoid valve.

Abstract: A valve system controls which air bags on a tractor trailer are in fluid communication with a pressurized air supply source. If one of the air bags develops a leak, an air bag may be taken out of fluid communication with the remaining air bags and pressurized air source. A pressure gauge monitors the air pressure within the valve system and air bags. A dump valve allows the air pressure within the system to be decreased.

Abstract: An Active Roll Control System for a motor vehicle that utilizes small valves to control large flows. Flow is supplied by a hydraulic pump which is powered in some fashion by the motor vehicle. Flow is directed to the actuators by a three-position-four-way valve that is controlled by two pairs of small ABS style solenoid valves. This allows for a minimum of power to be supplied by the vehicle to operate the system. Also, this valve arrangement allows a desirable failure mode whereby hydraulic fluid is locked into the hydraulic actuators, there by locking in the anti-roll bar in case of a system failure.

Abstract: A system for sensing relative position between chassis (5a, 5b) and axle (3) on a vehicle, which vehicle is provided with a so-called V-rod (1) mounted between the chassis (5a, 5b) and the axle (3) where the pointed end of the V is connected by a ball joint (2) to the axle (3) of the vehicle and the opposite ends (1a, 1b) of the V-rod (1) are connected to the chassis (5a, 5b) of the vehicle, which ball joint (2) comprises a partly ball-shaped body (8) permanently fixed to the axle or the v-rod, encircled by a complementarily shaped collar (9) arranged round the whole or parts of the ball-shaped body (8) which ball joint (2) is covered by a cap or housing.

Abstract: A control system, primarily for use with a vehicle, which increases ride stability and minimizes cycling of the control system during normal operation of the vehicle by utilization of a restriction valve to restrict the fluid introduced into or exhausted from a fluid bag in response to a received control signal.

Abstract: A system is provided for use on large vehicles of the type wherein the vehicle frame (12) is supported on vehicle axle assemblies (14, 20, 22) through air bags (26, 30, 32), and each air bag has a lower end coupled to the lower end of an arm such as a swing arm (112) whose upper end is pivotally mounted on the frame. The height of the air bag is sensed by a pair of tilt sensors (50, 52), one on a tilt arm such as the swing arm (112), that has one end pivotally connected to the vehicle frame and an opposite end at least pivotally connected to the vehicle axle assembly. The other sensor senses tilt of the vehicle frame about an axis parallel to the axes of pivoting of the tilt arm. Each tilt sensor senses tilt of its location with respect to gravity, and the difference in tilt indicates air bag height.

Abstract: A wheel bracket mechanism for an electric wheelchair equipped with auxiliary wheels, which comprises a frame, a pair of drive wheel brackets, four pedestal assemblies, a pair of caster brackets, a pair of oscillating assembly and a pair of anti-tipping brackets. The frame is provide with a pair of castor brackets at the front end and a pair of anti-tipping brackets at the rear end thereof, a pair of drive wheel brackets are secured to the frame with a front end stretching ahead of it and located between the castor brackets and the anti-tipping brackets, and between the castor brackets and the drive wheel bracket disposed an oscillating assemblies, four pedestal assemblies equipped with cushioning blocks are disposed at both sides of the front and rear end of the frame respectively in pairs with located opposite to each other.

Abstract: A lower arm assembly comprises a lower arm, a front fluid-filled bushing, a rear fluid-filled bushing, and a fluid transferring pipe extending between the bushings. Each of the front and rear bushings has an outer pipe, an inner pipe, and a shock absorbing member. A fluid chamber is formed within the shock absorbing member. The fluid transferring pipe connects the fluid chambers of the front and rear bushings together such that the fluid can transfer between the fluid chambers. Therefore, with the lower arm assembly according to the embodiment of the present invention, riding comfort and cornering stability can be simultaneously improved.

Abstract: The wheeled work vehicle according to the present invention has a link that links at least either one of the axles and provided at the front and the rear of the vehicle to a body, suspension hydraulic cylinders provided at the left side and the right side of the chassis to link the axle to the body in conjunction with the link and an accumulator that is made to communicate with oil chambers and of the hydraulic cylinders via restrictors.

Abstract: In addition to the consumers of a closed loop, known air supply systems also can supply an external consumer with fresh pressurized air. These systems are very complex with respect to apparatus and furthermore have the disadvantage that already improved pressurized air can escape from the pressurized air store during the supply of the external consumer. A switchable 3/2-directional valve (31) is arranged in the first consumer pressure line (19) of the drive unit (1) and a switchable 3/2-directional valve (32) is mounted in the store pressure line (11) of the drive unit (1) and a switchable check valve is mounted in the bypass line (16) of the store pressure line (11). This check valve disables the throttle function of the bypass throttle (17).

Abstract: A suspension system for a vehicle includes a frequency dependent damper (FDD) or shock absorber defining a first pressurized working chamber and an air spring assembly defining a second pressurized working chamber. A booster enables pressure communication between the first pressurized working chamber and the second pressurized working chamber. The booster includes a resilient member that effects booster performance.

Abstract: The suspension and level control system for vehicles includes, so as to independently control inflation and deflation of left and right front and rear air-springs, corresponding left and right front and rear pneumatic circuits in fluid communication with a pressurized air source. Each air-spring may have at least one air ride cushion reservoir mounted in a parallel pneumatic circuit in parallel fluid communication with the air-spring. Each pneumatic circuit includes a selectively actuable valve for selectively passing pressurized air from the air source into the corresponding parallel pneumatic circuit to selectively inflate the corresponding air-spring thereby raising a corresponding corner of the vehicle; and for selectively venting pressurized air from the corresponding parallel pneumatic circuit to selectively deflate the corresponding air-spring, thereby lowering a corresponding corner of the vehicle.

Abstract: A skid steer vehicle has a suspension that includes a control arm pivotally coupled to the vehicle chassis that is supported by a hydraulic cylinder connected to an accumulator to provide springing. A hydraulic circuit coupled to the cylinder and accumulator permit the operator to raise and lower the chassis, to lock the suspension while the vehicle is loaded, and to automatically charge or discharge the accumulator to match the cylinder pressure during loading and unloading. In this manner, when the suspension is unlocked after loading, the vehicle chassis neither rises nor falls.

Abstract: In a closed level control system for vehicles, a vehicle body is suspended relative to at least one vehicle axle. The level control system includes pressurized medium chambers, a compressor, an air dryer and a pressurized medium supply vessel which is partitioned into first and second pressurized medium spaces. The two pressurized medium spaces have no direct connection. Either the first pressurized medium space or the second pressurized medium space can be connected to the compressor input or the compressor output via at least one common controllable directional valve so that the pressurized medium from the pressurized medium chambers can be transferred into the first or into the second pressurized medium space or pressurized medium can be transferred from the first or the second pressurized medium space into the pressurized medium chambers.

Abstract: A sensor for a height control system in a trailing arm suspension uses a transducer to detect changes in position of a trailing arm relative to a vehicle and sends a proportional signal to a microprocessor that, in turn, actuates a pneumatic valve operably connected to an air spring between the trailing arm and the vehicle. The transducer includes an optical bridge, a variable capacitor, or a flexible variable resistor.

Abstract: An air suspension control system, primarily for use with a vehicle, which increases ride stability and minimizes air losses to the air suspension control system during normal operation of the vehicle by utilization of an air restriction valve to restrict the air introduced into or exhausted from an air spring in response to a received control signal.

Abstract: A device for converting electrical energy to mechanical energy is disclosed and claimed. The device includes a housing, a shaft, at least two coil assemblies, at least two magnets, and at least two electrical connectors. The shaft is supported by the housing and rotatable therein. The at least two coil assemblies are mounted to one of the housing and the shaft. The at least two magnets are mounted to the other of the housing and the shaft. The at least two electrical connectors are in communication with the at least two coil assemblies, wherein each of the at least two electrical connectors provide electrical energy to each of the at least two coil assemblies independently to generate a magnetic field in same, wherein the magnetic field interacts with the at least two magnets to produce an output torque on the shaft.

Abstract: A system is provided for use on large vehicles of the type wherein the vehicle frame (12) is supported on vehicle axle assemblies (14, 20, 22) through air bags (26, 30, 32), and each air bag has a lower end coupled to the lower end of an arm such as a swing arm (112) whose upper end is pivotally mounted on the frame. The height of the air bag is sensed by a pair of tilt sensors (50, 52), one on a tilt arm such as the swing arm (112), that has one end pivotally connected to the vehicle frame and an opposite end at least pivotally connected to the vehicle axle assembly. The other sensor senses tilt of the vehicle frame about an axis parallel to the axes of pivoting of the tilt arm. Each tilt sensor senses tilt of its location with respect to gravity, and the difference in tilt indicates air bag height.

Abstract: A hydraulic suspension strut (30) has a first on-off valve (58) connecting the first and second chambers (42 and 44), and a second on-off valve (62) connected to chamber (42) only. Suspension arm (3) of wheel (1) can be retracted beyond normal road travel, or protracted to road travel mode, by use of pump (9) and valves (58 and 62). The space in the strut above port (56) may be used as a hydraulic bump stop. An accumulator (50) may be included, as a hydraulic spring. Alternatively, strut (70) (FIG. 6; note alternative accumulator position) allows suspension to be raised above normal road travel. Strut (100) (FIG. 8) may be operated in roadgoing, raised, or retracted mode. These struts may be applied to reconfigurable suspensions; particularly for amphibious vehicles, which may require wheels to be withdrawn above the hull water line to reduce drag on water, particularly during cornering.

Abstract: Suspension system for a vehicle is disclosed and claimed. The suspension system includes a fluid, a suspension strut, a hydraulic cavity, an accumulator, and a volume modulator. The hydraulic cavity is at least partially defined by the suspension strut and is adapted to contain a portion of the fluid. The hydraulic cavity supplies a suspending spring force that biases a wheel of a vehicle toward the road surface. The volume modulator selectively pushes the compressible fluid into the hydraulic cavity and vents the compressible fluid from the hydraulic cavity, thereby actively modulating the suspending spring force.

Abstract: A method for controlling the storage pressure of a pressurized air store (4) of a closed level control system for a motor vehicle includes a compressor (6), a pressurized air store (4) (which can be filled with air from the atmosphere and which can be discharged into the atmosphere) and at least one air spring (2a to 2d). The air springs (2a to 2d) are connected via the compressor (6) to the pressurized air store (4) so that pressurized air from the air springs (2a to 2d) can be transferred into the pressurized air store (4) and can be transferred in the opposite direction. The storage pressure of the pressurized air store (4) is controlled indirectly via the air quantity in the level control system in that this air quantity is determined. The pressurized air store (4) is filled with air from the atmosphere when the air quantity lies below a lower limit and the pressurized air store (4) is discharged into the atmosphere when the air quantity lies above an upper limit.

Abstract: A suspension system that restricts side-to-side airflow between air springs on opposite sides of a vehicle or trailer. In one embodiment, active airflow discs in suspension ports of a valve operate in two modes; restrictive and non-restrictive. A disc attains a non-restrictive mode when air is exhausted from an air spring. A disc attains a restrictive mode when air is injected into the suspension port from the valve toward an air spring. Airflow discs in opposing suspension ports both attain a non-restrictive state to rapidly dump air from the springs and lower vehicle ride height. In another embodiment, a pneumatic circuit includes one-way check valves, in fluid communication with opposing air springs, aligned to restrict airflow between the opposing springs under uneven loading conditions. A pair of electronic solenoids acts in concert with the check valves to selectively inflate or deflate the air springs.

Abstract: In a process for controlling the quantity of air in a closed, chargeable and estimable pneumatic level control system of a vehicle, which level control system comprises at least one pressure sensor, one pump, an actuator, a storage reservoir and pressure lines interconnecting these components, at least one vehicle body level sensor, and a temperature sensor, which measures the ambient temperature, from the values measured an air mass of the level control system is calculated on the basis of the air pressures in the components, the level of the vehicle and the ambient temperature. Furthermore, the level of the vehicle, the ambient temperature and a maximum possible change in level from a particular vehicle level are used to calculate a vehicle-specific desired air mass and a desired air pressure in the system. The air mass is increased if the actual air pressure drops below the desired air pressure, and the air mass is reduced if the actual air pressure exceeds the desired air pressure.

Abstract: A lift-type axle/suspension system of a heavy-duty vehicle includes ride air springs for providing vehicle load support when the system is lowered, and one or more lift air springs for selectively raising the system when such additional load support is unnecessary or when greater vehicle maneuverability is desired. An apparatus integrates and simultaneously controls the operating systems for the lift and ride air springs. The control apparatus includes a plurality of conduits and valves which enable pressurized air from the lift air springs to be rapidly provided to the ride air springs when the system is being lowered. The additional air supplements the normal source of air from the vehicle compressed air source to ensure sufficient and timely air for smooth and efficient operation of the ride air springs without excessive buckling or folding, thus maintaining adequate overall vehicle air pressure needed for operating other vehicle components.

Abstract: A pneumatic switching valve (1) for systems for lifting and lowering the body of a vehicle including air suspension includes a mechanical actuation element (33) for adjusting a lifting position, a lowering position, a driving position and a stop position associated with respective positions of the vehicle. An inlet valve (11), an outlet valve (12) and a locking valve (13) each include a valve body (24), a tappet (26) and a closing spring (27). The inlet valve (11) and the outlet valve (12) are arranged in one common plane to face in opposite directions. The closing springs (27) of the inlet valve (11) and of the outlet valve (12) also serve to move the actuation element (33) from the lifting position or from the lowering position to the stop position when the operator releases the actuation element (33).

Abstract: In a method of making a cross member for a twist-beam axle of a motor vehicle, a band-shaped metal blank is shaped in a profiling unit in a continuous operation to a V-shaped or U-shaped double-walled hollow section having an outer wall and an inner wall, such that the outer wall of the hollow section extends, at least in an apex area thereof, at a distance to the inner wall of the hollow section, and that confronting longitudinal edges of the hollow section extend in the apex area of the outer wall. The confronting longitudinal edges of the hollow section are then joined by a longitudinal weld seam which is then smoothed. Subsequently the welded hollow section is cut to size to form a cross member.

Abstract: A method of controlling the roll stiffness and roll moment distribution of a vehicle suspension system of a vehicle, the vehicle suspension system including front and rear vehicle support means for supporting the vehicle and any load carried by the vehicle, and at least one roll moment reaction means for providing a variable roll stiffness for the vehicle suspension system;

Abstract: An air suspension system for a vehicle wherein a valve means for varying the resilience of an air spring in response to changes of vehicle height is integrally formed with an air spring to be mounted on the vehicle frame such that the installation space of the air suspension system can be minimized. As a result, cumbersome processes involved with the manufacture of the vehicle can be eliminated to provide an improved convenience for workers. A conventional lever used for connecting a leveling valve and an air spring is dispensed with to reduce the number of parts constituting the air suspension system and lower the manufacturing cost.

Abstract: The invention relates to a level adjusting system for motor vehicles, with a compressed air reservoir (26) and a tire inflation connector (28), in which a spare wheel can be connected. The spare wheel can be inflated from the compressed air reservoir (26) with the aid of the controllable distribution valve (36), the pneumatically controllable distribution valve (18), which bridges the non-return valve (10), the air dryer (6) and the pneumatically controllable valve (20) which also connects the compressed air line (22). The spare wheel may also be inflated with the aid of the compressor (2) and the pneumatically controllable distribution valve (20). During the inflation process the compressed air line (22) is closed with the aid of the controllable distribution valve (24) so that no compressed air escapes into the atmosphere.

Abstract: The invention relates to a suspension system, in particular for a working machine, such as a tractor or similar, with a suspension cylinder (10) subject to various load pressures (m), the piston-(12) and rod-side (14) of which may each be connected to a suspension reservoir (16, 18), by means of a stop device (20), which locks the suspension and with an equalization device (28) which comprises a switching valve (48) within the supply device, for controlling the piston side (12) of the suspension cylinder (10) and with a pressure supply (P) for supplying the system pressure necessary for the suspension system.

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 vehicular roll stabilizer used in a vehicle with an air suspension system, comprises roll sensing valve units traversely and centrally mounted on a vehicular body for receiving compressed air from an air tank to adjust the state of the compressed air respectively supplied to left and right air springs. Left and right roll sensing rods connect the roll sensing valve and axles, such that air inside the air springs can be directly controlled without using leveling valves and without enlarging the size of the stabilizer to actively obtain good resistance to rolling, thereby improving the performance 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: A lift axle suspension system to be mounted under a vehicle for selectively raising a tire wheel assembly out of engagement with a road surface which vehicle includes a lift axle mounted to a hanger bracket via a pivot connector. The hanger bracket is rigidly attached to a vehicle frame and has articulating arms pivotally connected thereto. These arms connect at their opposite ends to the axle. A pair of diaphragm chambers such as brake chambers each include upper and lower chambers separated by a flexible bladder that moves under pressurization causing a push rod affixed thereto to translate. The diaphragm chambers and push rods extending therefrom are connected in different embodiments to the hanger bracket or other rigid structures as well as the articulating arm such that movement of the push rods causes movement of the articulating arms and thus movement such as lifting of the axle.