A suspension system for a vehicle includes a knuckle defining a bore therethrough. The suspension system includes a wheel hub rotatably mounted on the knuckle. Further, the suspension system includes an axle at least partially received within the bore of the knuckle and operatively coupled to the wheel hub. The suspension system includes a pump driven by the axle and configured to generate pressurized fluid. The suspension system includes an actuator receiving pressurized fluid from the pump.

A hydraulic shock absorber includes a piston, a damper tube, a suspension spring, a plunger, a jack chamber, a pump case, a pump piston, a screw shaft, and a drive unit. Both end surfaces of the pump piston in a reciprocating direction are a first end surface demarcating the pump chamber, and a second end surface demarcating the gas chamber, the second end surface having a screw hole into which the screw shaft is screwed. The pump piston includes a space portion between a bottom plate defining the first end surface and the screw hole. The screw shaft has a through-hole connecting the gas chamber with the space portion.

A device for supplying hydraulic energy in a chassis system of a vehicle includes a first hydraulic pump and a first electric motor for driving the first hydraulic pump, a second hydraulic pump and a second electric motor for driving the second hydraulic pump, and a common electronic unit which is arranged to control the first and the second electric motor, wherein the two electric motors and the two pumps are preferably designed to be identical in structure and/or respectively form first and second motor-pump groups.

A device for supplying hydraulic energy in a chassis system of a vehicle includes a first hydraulic pump and a first electric motor for driving the first hydraulic pump, a second hydraulic pump and a second electric motor for driving the second hydraulic pump, and a common electronic unit which is arranged to control the first and the second electric motor, wherein the two electric motors and the two pumps are preferably designed to be identical in structure and/or respectively form first and second motor-pump groups.

A vehicle height adjustment device includes front forks, a rear suspension, a weight estimation unit, and a front wheel-side target movement amount determination unit. The front fork includes a front wheel-side suspension spring and a front wheel-side support member, which supports one end of the front wheel-side suspension spring, and moves toward another end of the front wheel-side spring to change the front wheel-side suspension spring length. The rear suspension includes a rear wheel-side suspension spring and a rear wheel-side support member, which supports one end of the rear wheel-side suspension spring, and moves toward another one end of the rear wheel-side spring to change the rear wheel-side suspension spring length. The weight estimation unit estimates a weight applied to a vehicle. The front wheel-side target movement amount determination unit decreases, a movement amount of the front wheel-side support member as the estimated weight increases.

A vehicle height adjustment device includes front forks, a rear suspension, a weight estimation unit, and a front wheel-side target movement amount determination unit. The front fork includes a front wheel-side suspension spring and a front wheel-side support member, which supports one end of the front wheel-side suspension spring, and moves toward another end of the front wheel-side spring to change the front wheel-side suspension spring length. The rear suspension includes a rear wheel-side suspension spring and a rear wheel-side support member, which supports one end of the rear wheel-side suspension spring, and moves toward another one end of the rear wheel-side spring to change the rear wheel-side suspension spring length. The weight estimation unit estimates a weight applied to a vehicle. The front wheel-side target movement amount determination unit decreases, a movement amount of the front wheel-side support member as the estimated weight increases.

Disclosed herein are various embodiments of a hydraulic actuator that includes one or more check valves having a dynamically varying cracking pressure. In certain embodiments, a hydraulic actuator may be configured to vary the cracking pressure of a check valve based on an operating condition of a pump of the hydraulic actuator. The check valve may be located along a bypass path in the hydraulic actuator, thereby allowing for fluid flow to bypass a pump of the hydraulic actuator by passing through the check valve. The use of such hydraulic actuators is contemplated in, for example, an active suspension system of a vehicle. Additionally, various embodiments of suitable check valves are disclosed. Additionally, methods are disclosed for operation of the check valve and the hydraulic actuator.

An air-spring assembly includes a flexible bellows extending from a top end to a bottom end and enclosing an air-spring chamber between the top end and the bottom end, a first panel partially defining the air-spring chamber and movable in response to a pressure of the air-spring chamber, an enclosure partially defining a working chamber fluidly isolated from the air-spring chamber, a second panel partially defining the working chamber and movable relative to the enclosure, and a linkage member fixed relative to the first panel and to the second panel and defining a fixed distance between the first panel and the second panel. The top and bottom ends are fixable to a frame and a wheel of a vehicle, respectively. A volume of the air-spring chamber varies with movement of the bottom end relative to the top end. Movement of the second panel changes a volume of the working chamber.

Disclosed herein is a spring preload system comprising a cylinder with an outer diameter, a body to house at least the cylinder, a piston shaft, and a main damping piston. The main damping piston is coupled to the piston shaft and configured for operation within the cylinder. The main damping piston is further configured to divide the cylinder into a compression side and a rebound side. The spring preload system further comprises a preload cylinder and a valve that is fluidly disposed between the compression side and the preload cylinder.

A vehicle height adjustment device includes a spring having one end supported on a vehicle body side and another end supported on a wheel side. An adjustor includes an accommodation chamber accommodating fluid and adjusts a length of the spring in accordance with an amount of fluid in the accommodation chamber. A storage chamber stores fluid. A guide passage guides fluid from the accommodation chamber to the storage chamber. An actuator includes an operation rod to press a push rod. A valve body closes the guide passage when seated on a seat and opens the guide passage when pressed and detached from the seat by the push rod. A press member includes a contact portion and a shaft. The press member presses and seats the valve body on the seat. An accommodation member accommodates the valve body and the contact portion. A support member supports the shaft movably.