Abstract: In order to avoid pressure and volume compensation as much as possible during measurement of the pressures of air spring units, the pressure in the air spring units (5, 6, 7, 8) is estimated prior to measurement of the pressures of the air spring units (5, 6, 7, 8) and is compared to the pressure in the air pressure accumulator (3). The higher of the two pressures determines the position of a 3/2 directional control valve (11) which separates the collector line (25) connecting all air spring units (5, 6, 7, 8) from the air pressure accumulator (3) or which connects it to as small a chamber volume of the supply system as possible.

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: In order to simplify air flow control in a self-contained air supply system, an average control speed is calculated on the basis of a defined movement of the air springs (3, 4) and compared with an optimum control speed. The result of the comparison of the control speeds is used to determine the need for or the excess of an amount of compressed air. There are at least three possibilities for calculating the average control speed.

Abstract: An articulated loader has an articulated chassis and two A-frames. The points of the A-frames face each other. The articulated chassis includes a front portion and a rear portion. Likewise, there is a front or first A-frame and a rear or second A-frame. The A-frames are connected to the overall chassis at points close to but offset from the point of vehicle articulation via ball joints and via hydraulic suspension cylinders toward the wider portions of the “A”s. The vehicle is propelled along the ground by tracks that are independently suspended. The invention includes a suspension lockout feature to, effectively lockout the suspension system, i.e., render it rigid. One or more valves may are used to prevent hydraulic flow from and two the hydraulic suspension cylinders.

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 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: A significant advantage of this system is that it captures and utilizes a distinctive amount of energy that normally is lost. Also, it is a system that the vehicle manufacturers can easily build into their ‘ready for market’ models or it may be offered to vehicle owners as a DIY attachment to their vehicles. While it should be apparent to those knowledgeable in the art of hydraulics, this system may be adaptable to other applications, hydraulic or not, where energy is being lost or wasted to conserve that energy. Most of the vehicle references in this specification have been made to automobiles, but it should be pointed out that the applicability of the proposed system to trucks is very sound and worthwhile. With worldwide emphasis now on energy conservation, this system provides a realistic cost-saving means.

Abstract: A shock absorber includes a dynamic vibration absorber which is designed to suppress the vibrations of the piston rod of the shock absorber. The dynamic vibration absorber includes a damping mass which is formed as a dirt shield to protect the shock absorber from contaminants.

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: In a suspension system (20) for use in a vehicle including a body, left and right front wheels (10), and left and right rear wheels (12), a front-wheel-associated cylinder device (52) which controls a relative displacement of the left and right front wheels, and a rear-wheel-associated cylinder device (62) which controls a relative displacement of the left and right rear wheels are associated with each other with a working fluid. A first-chamber-associated valve (190) is provided in a first-chamber-associated passage (90) which connects between respective first chambers (74) of the front-wheel-associated cylinder device and the rear-wheel-associated cylinder device, such that the first-chamber-associated valve is located between the first chamber of the front-wheel-associated cylinder device and a first fluid accommodating device (200).

Abstract: Four shock absorbers are connected to a control cylinder. The control cylinder includes a housing body portion having two cylinder chambers which are divided by a partition wall portion; and a piston assembly which is formed by coupling two pistons with each other using a coupling rod. Two outer side control chambers and two inner side control chambers are connected to respective absorber chambers. Pressure receiving areas of outer side pressure-receiving surfaces and inner side pressure-receiving surfaces of the pistons and damping characteristics of the shock absorbers are set such that a direction in which the piston assembly moves in a region where an operation speed is low is opposite to a direction in which the piston assembly moves in a region where the operation speed is high.

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 being hydraulically connected to one another in a cross connection, so that a piston-side chamber of the one hydraulic cylinder is connected to the piston rod-side chamber of the other hydraulic cylinder and vice versa, in each case one hydraulic accumulator assigned to a hydraulic cylinder, a hydraulic source, a hydraulic tank, a control valve device, an electronic control init, electrically switchable switch valves which are arranged in the cross connection between the hydraulic accumulators and the hydraulic cylinders, and a first and second supply line, which supply lines connect the control vale device to the cross connection.

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: 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 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 for vehicles. The invention relates to both double axle vehicles and single axle vehicles. Feasible areas of use are: prams, carts (pulled manually or by a vehicle), walkers, wheel chairs, skateboards, luggage carts and motor vehicles. It is significant for the wheel suspension that the centre axles (15a, 15b) of wheels (11a, 11b) of a set of wheels are connected to elements (14a, 14b) that extend in the travelling direction of the vehicle, that these elements (14a, 14b) are hingedly/pivotally connected to a frame (1?) of the vehicle, that the centre axles (15a, 15b) for adjacent wheels (11a, 11b) are located at a certain distance from each other in the longitudinal direction/travelling direction (2) of the vehicle.

Abstract: A vehicle suspension system of a motor vehicle includes a plurality of suspension devices mounted on the vehicle with respect to right and left wheels of the vehicle, respectively, a first behavior controller that controls the motion of each of the suspension devices when a vehicle body undergoes a first behavior, and a second behavior controller that controls the motion of each of the suspension devices when the vehicle body undergoes a second behavior, independently of the first behavior controller.

Abstract: An articulated loader has an articulated chassis and two A-frames. The points of the A-frames face each other. The articulated chassis includes a front portion and a rear portion. Likewise, there is a front or first A-frame and a rear or second A-frame. The A-frames are connected to the overall chassis at points close to but offset from the point of vehicle articulation via ball joints and via hydraulic suspension cylinders toward the wider portions of the “A”s. The vehicle is propelled along the ground by independently driven tracks. The invention includes a feature to limit the motion of the suspension system based on the load applied to the suspension cylinders, i.e., the pressure experienced by the head end of the suspension cylinders. This is accomplished via pilot operated check valves.

Abstract: A suspension system for a vehicle for use on any terrain. The suspension system (70) includes a plurality of fluid-operated cylinders (6, 7, 8, 9) which are each configured to interconnect wheels (1, 2, 3, 4) of the vehicle to the chassis (5). Fluid flow communication between the fluid-operated cylinders (6, 7, 8, 9) is achieved via tubes (15, 16, 17, 19) which extend between operative upper or lower chambers of fluid-operated cylinders (6, 7, 8, 9).

Abstract: In a suspension system (20) for use in a vehicle including a body, left and right front wheels (10), and left and right rear wheels (12), a front-wheel-associated cylinder device (52) which controls a relative displacement of the left and right front wheels, and a rear-wheel-associated cylinder device (62) which controls a relative displacement of the left and right rear wheels are associated with each other with a working fluid. A first-chamber-associated valve (190) is provided in a first-chamber-associated passage (90) which connects between respective first chambers (74) of the front-wheel-associated cylinder device and the rear-wheel-associated cylinder device, such that the first-chamber-associated valve is located between the first chamber of the front-wheel-associated cylinder device and a first fluid accommodating device (200).

Abstract: A suspension system, in particular for a working machine, such as a tractor or similar device, with a suspension cylinder (10) is subjected to various load pressures (m). The piston slide (12) and rod side (14) of the system may each be connected to a suspension reservoir (16, 18). A locking device (20) locks the suspension and, with an equalization device (28) having a switching valve (48) within the supply device, controls the piston side (12) of the suspension cylinder (10). A pressure supply (P) supplies the system pressure necessary for the suspension system. A pressure equalization of the system to the relevant load pressure can be performed before renewed operation by the equalization device. The equalization device (28) includes a further switching valve (50) within the supply device (30) for control of the rod side (14) of the suspension cylinder (10). A load monitoring device (LS) is connected to parts of the stop device (20).

Abstract: A roll control system for a motor vehicle comprising a torsion bar (16); a first hydraulic actuator (12) connected to one end (20) of the torsion bar and connectable to an axle (34) of the vehicle; a second hydraulic actuator (14) connected to the other end (28) of the torsion bar and connectable to the axle of the vehicle; a hydraulic control system (62) connected to the hydraulic actuators and including a source of fluid pressure (66), a fluid reservoir (68), at least one supply valve (74, 76), and a pressure control valve (70); and an electrical control system (64) controlling the hydraulic system dependent on sensed vehicle conditions; wherein each hydraulic actuator comprises a rebound chamber (42, 52) and a compression chamber (40, 50) separated by a piston (38, 48), and a piston rod (18, 26) attached to the piston and extending through and out of the rebound chamber; wherein, during straight line motion of the vehicle, the electrical control system actuates the supply valve or valves to isolate the reb

Abstract: A suspension system for a vehicle, having at least first and second shock absorbers. The first shock absorber has a first main piston, and the second shock absorber has a second main piston. The shock absorbers are motively linked such that when the first main piston retracts, the second main piston is also caused to retract. The first and second shock absorbers may be hydraulic shock absorbers, wherein the first shock absorber defines a first hydraulic chamber therein, and the second shock absorber defines a second hydraulic chamber therein, the first and second hydraulic chambers being connected with a hydraulic line, so that causing the first main piston to retract reduces the size of the first hydraulic chamber, which increases the size of the second hydraulic chamber, which then causes the second main piston to retract. The suspension system may include an adjustor for convenient adjusting of the suspension system.

Abstract: A hydraulic tilting device for tilting a cab mounted on the chassis of a vehicle between a driving and a tilted position comprises a reservoir for hydraulic fluid, a pump connected to the reservoir, and a double-acting hydraulic tilting cylinder. A lost-motion conduit is provided between ports opening into a push chamber and a pull chamber in the cylinder space of the tilting cylinder when the piston/piston rod assembly is in a lost-motion range defined by the ports. When under the influence of the movements of the piston/piston rod assembly within the lost-motion range, the pull connection of the tilting cylinder causes suction of hydraulic fluid out of the reservoir, forcing hydraulic fluid from the reservoir into the pull chamber, and moving hydraulic fluid from the pull chamber to the reservoir through the lost-motion conduit. Hydraulic fluid therefore circulates when the cab is carrying out spring movements.

Abstract: A suspension system including a pneumatic leveling system adapted to selectively receive and expel a fluid and a spare tire in communication with the leveling system, wherein the spare tire is adapted to provide the fluid to the leveling system.

Abstract: A method and apparatus is provided for estimating the mean pressure in a compressible fluid strut. A database is employed containing values for mean pressure variation corresponding to a specific combination of motor speed and flow demand, and may also account for strut temperature. The flow demand and the speed of the motor are determined, and the mean variation corresponding to the determined combination of motor speed and flow demand is selected. The estimation of strut mean pressure is updated with the selected mean pressure variation. In this way, costly pressure sensors are eliminated as well as the complicated control algorithms which are used therewith.

Abstract: The present technique provides a stabilizer system comprising a plurality of piston cylinder assemblies, which have multiple interconnected chambers to provide cross compensation between suspension members coupled to those piston cylinder assemblies. The piston cylinder assemblies may have two or more chambers separated by pistons, which move in response to a load imposed on the suspension member coupled to that piston cylinder assembly. As the piston moves in response to movement of the corresponding suspension member, a fluid pressure is transmitted to another suspension member to distribute the load between the two suspension members.

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: A method and apparatus for adaptively damping relative motion between the wheels and the frame of a heavy duty truck having a frame suspended on wheels by a suspension system. An air spring is disposed between the frame and at least one of the wheels having a primary reservoir for holding air and a piston adapted to act upon the air in the reservoir to compress the air and thereby provide support for the frame. An auxiliary reservoir holds air and can be placed in fluid communication with the primary reservoir to increase an effective volume of air upon which the piston acts. A control valve selectively places the auxiliary reservoir in communication with the primary reservoir based on vehicle operating parameters. The control valve can be actuated mechanically by forces acting on the wheels or by a controller that controls the valve based on wheel torque and road roughness.

Abstract: The wheeled work vehicle according to the present invention comprises a link 4 that links at least either one of axles 1 and 1′ provided at the front and the rear of the vehicle to a body 70, suspension hydraulic cylinders 2 provided at the left side and the right side of the chassis 70 to link the axle 1 to the body 70 in conjunction with the link 4 and an accumulator 7 that is made to communicate with oil chambers 2b and 2c of the hydraulic cylinders 2 via restrictors 5a, 5b and 6a.

Abstract: The invention relates to a vehicle for carrying persons and/or cargo. This vehicle comprises an automotive frame having at least two wheels (2), which are disposed on opposite sides of the vehicle with reference to the longitudinal axis, or substanntially aligned along the longitudinal axis of the vehicle, and are provided with elastic suspensions, which are driven by any type of kinematic system, composed by at least one elastic element (103, 105) of any type. The vehicle is characterized in that the suspensions of the individual wheels are connected with each other by means of any mechanical, hydraulic, pneumatic, electrical or magnetic system or any combination thereof, at least one elastic element (105) acting thereon, and in that the reaction to the stress exerted by one of the connected wheels transfers, at least partly, a stress on the corresponding connected wheel/s and in that elastic opposing elements (103) are provided on each wheel.

Abstract: An air suspension for a vehicle includes at least one air spring per wheel at at least one vehicle axle, one pump, at least one accumulator, and one circuit arrangement for connecting these units, the pressure side of the pump being connected to the accumulator or the air springs. To form a closed compressed-air system, the intake side of the pump is connected via at least one valve to the accumulator or the air springs, and at least the air-guiding interior pump chambers between the intake side and the pressure side of the pump have a pressure-tight design. The air suspension system requires comparably low energy consumption and small unit volume at a high level of efficiency.

Abstract: A number of embodiments of four-wheeled vehicle suspension systems have interrelated front and rear shock absorbers so as to provide good control under normal suspension travel as well as resistance toward leaning, pitching, diving and squatting. In each embodiment, the normal fluid dampers having only a single shock absorber valve therein are interrelated with pressure controls that comprise four hydraulic cylinder portions which communicate with each other through various paired arrangements so as to provide this control and simplification of damping.

Abstract: A vehicle suspension has one or more hydraulic cylinders connecting an axle to a frame of the vehicle and each cylinder has a first and second chambers. The suspension operates in either a regeneration mode, in which a fluid path is provided between the first and second chambers, and a double acting mode, in which the first and second chambers are isolated from each other and fluid flows between each chamber and a separate accumulator. The selection between the regeneration and double acting modes is made in response to the pressure level in the cylinder as determined by a pressure sensor of a closed loop control system or by the pressure versus current characteristics of a electrically operated valve in the suspension for a loop control system. The hydraulic system also is able to raise and lower the suspension as necessary due to changes in the load carried by the vehicle.

Abstract: Suspension system for a vehicle is disclosed and claimed. The suspension system includes a compressible fluid, a suspension strut, a hydraulic cavity, a reservoir, 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 compressible fluid. The hydraulic cavity and the compressible fluid supply 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 modulating the suspending spring force.

Abstract: An anti-roll suspension system for a motor vehicle includes a plurality of double-acting cylinders coupling the unsprung and sprung portions of the vehicle. The upper fluid chamber of each cylinder is exclusively connected to the lower fluid chamber of the laterally opposite cylinder to create a fluid circuit having first and second portions which hydraulically link the cylinders. When the vehicle is subjected to a centrifugal force, the position of the sprung portion rotates relative to the position of the unsprung portion of the vehicle. This relative rotation is resisted by the tendency to substantially equalize the forces acting on pistons of the first and second cylinders, thereby reducing the tendency of the sprung portion of the vehicle to roll. An alternate embodiment includes a valve which is operable in either of a recirculating mode and cross-flow mode.

Abstract: A suspension control system includes a load support member, a base member and a moveable element attached to the base member and the load support member. The load support member is moveable relative to the base member through the moveable element. A accumulator is in fluid communication with the moveable element. A locking circuit is disposed between the moveable element and the accumulator and is selectively activatable to sustain said load support member in a fixed position. The locking circuit includes a pressurized fluid supply and a flow blocking mechanism operably engaged with the pressurized fluid supply. The flow blocking mechanism is urged to block fluid communication between the moveable element and the accumulator when the locking circuit is selectively activated.

Abstract: A vehicle suspension system including a first and second hydraulic damper is provided. Each hydraulic damper is provided with a cylinder and a piston connected to one end of a hollow piston rod, such that the pistons freely slide in the cylinder. The system also includes a pressure regulator, which has a first and second oil chamber connected to the first and second hydraulic dampers, respectively. The system additionally comprises a sub-piston and another piston connected to the sub-piston, which slidably engage in the hollow piston rod, forming an oil chamber.

Abstract: A device to control the dynamic stability of an industrial vehicle, where the chassis of the aforesaid vehicle is fitted with a pair of axles (10′, 10″), extending from each of which are booms (12, 13, 12′, 13′), fitted to the ends of which are articulated steering pivots (14, 15, 14′15′) of the wheels of the aforesaid vehicle and where interposed between the axle (11) and the frame (16) of the aforesaid industrial vehicle are hydraulic cylinders (17, 17′, 18, 18′), said control device providing that each hydraulic cylinder (17, 17′, 18, 18′) is associated with pressure transducers capable of indicating the loads weighing instantaneously on each wheel hub, thus permitting, by means of appropriate data processing, detection of the condition of stability of the vehicle, said pressure transducers (31-34) being associated with hydraulic cylinders (17, 17′, 18, 18′) so as to operate in real time to provide the initial data to process the condi

Abstract: An apparatus (12) for use in a vehicle suspension (10) comprises an anti-roll bar (28) having opposite first and second end portions (30 and 32). An intermediate portion (34) is interposed between the first and second end portions (30 and 32) and is subjected to torsional forces when the first and second end portions (30 and 32) move relative to one another. The apparatus (12) further comprises an actuator (48) for attaching at least one of the first and second end portions (30 and 32) to a part of the vehicle suspension (10). The actuator (48) comprises a cylinder (52) for retaining fluid (54) and a piston assembly (56) for dividing the cylinder into two chambers (81 and 83). The piston assembly (56) is movable axially within the cylinder (52). The piston assembly (56) includes structure forming orifices (144) for interconnecting the two chambers (81 and 83) of the cylinder (52).

Abstract: A vehicle suspension control system that allows substantially vertical motion of each wheel relative to the vehicle body includes front and rear resilient support means for supporting the body, a front roll stabilization assembly interconnecting at least one forward pair of wheels and a rear roll stabilization assembly interconnecting at least one rearward pair of wheels. Each roll stabilization assembly includes at least one lateral torsion bar (2) and a double-acting hydraulic actuator (3) interconnected to the at least one lateral torsion bar (2), the front and rear hydraulic actuators (3) being interconnected by first and second fluid conduits (5). Roll moments applied to the vehicle body generate pressure within the fluid conduits (5) thereby transmitting the roll moment into each lateral torsion bar (2).

Abstract: The invention relates to a system which includes an air spring (2) which, in turn, encloses an air volume (16). The system also includes a controllable shock absorber (4) connected in parallel to the air volume. Furthermore, the system includes an ancillary volume (22) with which the air volume (16) of the air spring (2) is connected via a controllable throttle (20). The stiffness and the total damping of the system can be pregiven via a control of the throttle (20) and of the controllable shock absorber (4) independently of each other.

Abstract: A trailing arm suspension, alone or in combination with a vehicle having a vehicle frame supported by an axle with ground engaging wheels. The trailing arm suspension comprises a pair of spaced trailing arm assemblies, each of which includes a trailing arm pivotally mounted to a the vehicle frame and a spring operably coupling the trailing arm to the frame to resist the pivotal movement of the trailing arm. A pneumatic lift mechanism is provided to selectively raise the trailing arm relative to the frame. The axle has at least a portion of which that is hollow and defines a pressurized air reservoir, which is coupled to the spring and/or the pneumatic lift mechanism to provided pressurized air for altering the resistance of the spring and/or actuating the pneumatic lift mechanism to selective lift the trailing arm.

Abstract: A hydraulic circuit controls a doubling acting cylinder of a vehicle suspension to provide load leveling and shock absorption functions. A set of solenoid valves control the application of pressurized hydraulic fluid from a supply line to the cylinder and from the cylinder to a tank return line to raise and lower the vehicle for load leveling. The chambers of the cylinder are interconnected by a parallel arrangement of a check valve, orifice and a relief valve. Another parallel arrangement of a check valve, orifice and a relief valve couples the cylinder to an accumulator. These parallel arranged components enable the doubling acting cylinder to function as a passive shock absorber. A lock-out valve is provided in the preferred embodiment a to defeat the shock absorber operation and provide a very stiff suspension.

Abstract: A vehicle suspension system includes a hydraulic anti-roll mechanism in which a pair of suspension arms (10a, 10b), on opposite sides of the vehicle, are mounted to the vehicle body pivots (16a, 16b). A pair of hydraulic struts (22a, 22b) are connected between the suspension arms and the body (14). The struts are asymmetrically mounted so that one is inboard of its suspension arm pivot and the other is outboard of its suspension arm pivot. The two lower chambers of the struts (22a, 22b), through which the connecting rods (32) of the pistons extend, are hydraulically interconnected, and so are the two upper chambers.

Abstract: A hydraulic suspension system for a crop sprayer includes a first damping cylinder and a second damping cylinder. The suspension system also includes a first leveling cylinder which is fluidly coupled to the first damping cylinder via a first leveling fluid line and a second leveling cylinder which is fluidly coupled to the second damping cylinder via a second leveling fluid line. The suspension system further includes a first accumulator which is fluidly coupled to the first damping cylinder via a first damping fluid line and a second accumulator which is fluidly coupled to the second damping cylinder via a second damping fluid line. The first damping fluid line possesses a first diameter, whereas the first leveling fluid line possesses a second diameter. The second damping fluid line possesses a third diameter, whereas the second leveling fluid line possesses a fourth diameter. The first diameter is greater than the second diameter and the third diameter is greater than the fourth diameter.

Abstract: The invention relates to a level control arrangement for vehicles having air springs (6a) to (6d) and a pneumatically controllable directional valve (26). A residual pressure holding function and an overpressure function are integrated into the directional valve (26). The directional valve (26) is controlled by the air pressure in the air springs (6a) to (6d). The air pressure can be applied via a control line (20) to a control input (24) of the directional valve (26). The air from the air springs (6a) to (6d) is released with the aid of the venting line (28). The venting line (28) is guided separately from the control line (20) through the directional valve (26). In this way, a large air flow can be conducted through the venting line (28) without the static air pressure in the control space (50) of the directional valve (26) being reduced. The venting line is blocked by a stepped piston (44) of the directional valve when no air is to be released from the air springs.

Abstract: A suspension system for a vehicle tandem axle has air springs positioned adjacent the ends of the trailing and lead axles of the tandem axle. Pairs of air springs on each side of the vehicle are pneumatically connected to form a common reservoir. Displacement of the ends of the lead and trailing axles of the tandem axle are averaged to provide a controlling input to air spring pressurization controllers provided for each pair of air springs.

Abstract: A load distribution unit is utilized in a vehicle suspension system having at least one pair of laterally adjacent forward wheel assemblies, and at least one pair of laterally adjacent rear wheel assemblies. A wheel ram is associated with each of the wheel assemblies, each wheel ram including a major chamber therein. The load distribution unit includes a plurality of fluid chambers, each fluid chamber being divided into at least two control chambers by at least one piston supported therein. Two pairs of the control chambers which vary in volume proportionally and in opposite senses therein with piston motion are system chambers, and at least two of the remaining control chambers are bump chambers. The pistons are interconnected by at least one connection device. The major chamber of each wheel ram is in fluid communication with a respective system chamber. The vehicle suspension system provides a roll stiffness and a pitch stiffness while providing minimum cross-axial articulation stiffness.

Abstract: A suspension system for a vehicle includes a first hydraulic circuit, a second hydraulic circuit and a connection between the first hydraulic and the second hydraulic circuit. The first hydraulic circuit is operatively coupled to a first side of the vehicle, and is selectively controllable to move the first side of the vehicle. The second hydraulic circuit is operatively coupled to a second side of the vehicle, and is selectively controllable to move the second side of the vehicle. The first hydraulic circuit and the second hydraulic circuit operate together in a first mode when the connection between the first hydraulic circuit and the second hydraulic circuit is opened to move the first and second sides of the vehicle in a same direction. The first hydraulic circuit and the second hydraulic circuit operate independently of each other in a second mode when the connection is closed.