A spring-damper system includes at least a differential cylinder (4), a hydraulic accumulator (26) and a control valve device (1, 2). By at least one motor-pump unit (22), pressure fluid can be supplied to the annular end (6) or both the annular end (6) and the piston end (8) of the differential cylinder (4) in a closed circuit using the control valve device (1, 2).

A shock-absorbing front fork assembly of a motorcycle includes a front fork, a pressure buffering cylinder and a control valve disposed between the front fork and the pressure buffering cylinder and electrically connected with a brake system to control the communication between the front fork and the pressure buffering cylinder according to the operation of the brake system. When the brake system is not actuated, the control valve is open to make the front fork communicate with the pressure buffering cylinder, thereby making the spring supporting force relatively smaller. When the brake system is actuated, the control valve is close to make the front fork not communicate with the pressure buffering cylinder, thereby making the spring supporting force relatively larger. Therefore, the spring supporting force is adjusted by the brake operation, that raises the riding comfort and safety.

An electric height control device may include: an oil storage part configured to store oil therein; a motor driving part inserted into the oil storage part and driven when power is applied thereto; a hydraulic block part coupled to the motor driving part, connected to the oil storage part, and configured to amplify oil; and a control part coupled to the hydraulic block part, and configured to control the motor driving part and the hydraulic block part.

A suspension system for controlling movement of a vehicle wheel may include a spring and damper assembly coupling the wheel to the vehicle chassis for movement of the wheel relative to the vehicle chassis. The spring and damper assembly may include a spring coupled to a damper member configured to extend and retract the wheel relative to the vehicle chassis. The suspension system may further include a damper actuator located remotely from the spring and damper assembly and configured to modify an amount of damping and/or wheel extension. The suspension system may also include a spring actuator integrated with the damper actuator and configured to control an amount of deflection of the spring and/or to alter a spring rate. The damper actuator may be provided at a location in the vehicle separated from the spring and damper assembly.

Methods and systems for vehicle suspension are provided. A leveling manifold includes, in one example, a plurality of electrically-activated valves arranged between, on a first end, a rod-side and a piston-side of one or more hydraulic cylinders, and on a second end, a pressure source and a tank, wherein the plurality of electrically-activated valves include a first valve, a second valve, a third valve, and a fourth valve. The leveling manifold further includes a first flow path extending through the first and second valves and from the rod-side to the second end and a second flow path extending through the third and fourth valves and from the piston-side to the second end, the leveling manifold is designed to manage operation of the first, second, third, and/or fourth valves to independently adjust a position and a stiffness of the one or more hydraulic cylinders.

An air suspension apparatus includes a compressor configured to compress air, a tank configured to store the air, a tank-side suction conduit configured to supply the compressed air in this tank to an intake side of the compressor, a tank conduit connecting a discharge side of the compressor and the tank, an air suspension connected to the discharge side of the compressor via an air drier, an intake electromagnetic valve provided in the tank-side suction conduit, a return electromagnetic valve provided in the tank conduit, and a discharge conduit provided so as to branch off from between the discharge side of the compressor and the air drier and configured to be connected to an atmosphere by opening a discharge electromagnetic valve.

Methods and systems for vehicle suspension are provided. A leveling manifold includes, in one example, a plurality of electrically-activated valves arranged between, on a first end, a rod-side and a piston-side of one or more hydraulic cylinders, and on a second end, a pressure source and a tank, wherein the plurality of electrically-activated valves include a first valve, a second valve, a third valve, and a fourth valve. The leveling manifold further includes a first flow path extending through the first and second valves and from the rod-side to the second end and a second flow path extending through the third and fourth valves and from the piston-side to the second end, the leveling manifold is designed to manage operation of the first, second, third, and/or fourth valves to independently adjust a position and a stiffness of the one or more hydraulic cylinders.

Methods and systems for hydraulic vehicle suspension are provided. A hydraulic suspension system, in one example, includes a first manifold including a piston-side interface and a rod-side interface fluidically coupled to a piston chamber and a rod chamber, respectively, for each of a first hydraulic cylinder and a second hydraulic cylinder. In the system, the first manifold includes a first electrically activated valve fluidically coupled to the piston-side interfaces, a first damping device, and a second damping device, the first electrically activated valve is configured to lock and unlock vertical motion of the first and second hydraulic cylinders and, while vertical motion of the first and second hydraulic cylinders is locked, the first electrically activated valve permits fluidic communication between the first and second hydraulic cylinders to permit free roll motion in the hydraulic suspension system.

An air management system for a vehicle. The air management system includes at least one air spring. A compressor is provided for filling the air spring. A central air line is fluidly connected to the air spring and the compressor. At least one spring air line extends between the central air line and the air spring. At least one suspension valve is disposed along the spring air line. At least one auxiliary air line extends between the spring air line and the central air line. At least one high flow exhaust valve is disposed along the auxiliary air line. At least one isolation check valve is disposed in series with the high flow exhaust along the spring air line. The isolation check valve allows air to pass through therethrough from the air spring to the central air line while preventing air from passing therethrough from the central air line to the air spring.

A vehicle-height control system includes: a vehicle-height control actuator; a pressure-medium supply and discharge device configured to supply and discharge a pressure medium; and a vehicle height controller configured to control a vehicle height by controlling the pressure-medium supply and discharge device. The pressure-medium supply and discharge device includes a compressor and a tank configured to contain a pressure medium supplied from the compressor. The vehicle height controller includes a down controller configured to operate the compressor to discharge and supply the pressure medium from the vehicle-height control actuator to the tank to lower the vehicle height when a tank pressure is less than a set pressure. The down controller is configured to discharge the pressure medium from the vehicle-height control actuator to an outside to lower the vehicle height when the tank pressure is greater than or equal to the set pressure.