An active suspension system is configured in a strut arrangement. The active suspension system comprises a hydraulic actuator and a hydraulic pump/electric motor assembly, wherein the actuator movement is preferably in lockstep with the hydraulic motor-pump and electric motor-generator combination. Torque in the electric motor is instantaneously controlled by a controller to create an immediate force change on the hydraulic actuator. The hydraulic actuator is configured so that it can be used as a strut whereby the actuator has sufficient structural rigidity to carry the applied suspension loads while capable of supplying damper forces in at least three quadrants of the force velocity graph of the suspension actuator operation. Embodiments disclosed include low cost active suspension systems for a MacPherson strut application.

A hydraulic level-adjustment device has a reservoir, a reversible hydraulic unit with a hydraulic pump, and a single-acting hydraulic linear actuator. To lift a vehicle chassis, the working space of the linear actuator can be pressurized by the hydraulic pump operated in its first pumping direction via its first pump connection and a fill line with a fill-check valve arranged therein. To lower the chassis, via its second pump connection, the hydraulic pump, operated in the reverse pumping direction, pumps hydraulic fluid into the reservoir via an outflow line with a throttle unit arranged therein. The pressure present upstream of the throttle unit acts on the control connection of a lockable, drainage-check valve via a control line and opens same, so that, under the weight of the motor vehicle, hydraulic fluid is forced out of the working space of the hydraulic linear actuator into the reservoir via the drainage line.

A suspension device includes an actuator device provided with an extensible/contractible actuator body interposed between a sprung member and an unsprung member of a vehicle, a pump that supplies fluid to the actuator body to extend or contract the actuator body, and a controller that controls a rotation number of the pump. The controller has a road surface state index obtainment unit that obtains a road surface state index and a target rotation number determination unit that determines a target rotation number of the pump on the basis of the road surface state index.

The invention relates to a vehicle seat or a vehicle cab with a suspension system comprising an upper closing part and a lower closing part which is deflectable in relation to the upper closing part, which closing parts are operatively connected to each other in a resilient manner by means of a suspension element, and with a damping system for damping vibrations acting on at least one of the two closing parts, wherein an electromagnetically acting damping and height-levelling unit is provided which is arranged between the two closing parts in such a manner that said damping and height-levelling unit acts on the upper of the two closing parts in the vertical direction of the vehicle both in a vibration-insulating and also height-levelling manner.

Provided is a damper with which the energy efficiency for attenuating input vibration corresponding to the unsprung resonance frequency and the sprung resonance frequency can be improved. Also provided is a method for manufacturing this damper. In this damper the electrical resonance frequency, as specified by the inductance of an electromagnetic motor and the capacitance of a capacitor, is set within ±20% of the unsprung resonance frequency, thereby enabling the input vibration corresponding to the sprung resonance frequency as well as the input vibration corresponding to the unsprung resonance frequency to be reduced.

An adjustable vibration damper has at least one adjustable damping valve, a piston at a piston rod that divides a cylinder into a work chamber on the piston rod side and a work chamber on the side remote of the piston rod. A hydraulic device is connected via a first line to the at least one adjustable damping valve connected to one of the work chambers and via a second line at least indirectly to the other working chamber.

Active suspension actuator systems including an actuator with a compression volume and an extension volume are described. In some embodiments, the system includes one or more flow control devices in fluid communication with the compression volume and/or the extension volume of the actuator. In some instances, a flow control device may include a pressure balanced blow-off valve (PBOV). In some embodiments, the system includes a high capacity bidirectional base valve. In some embodiments, two or more flow control devices cooperate to, for example, damp low amplitude oscillations in the extension and/or compression volumes, and to allow the build-up of pump generated differential pressures while discharging rapid road induced differential pressure spikes between the extension and compression volumes.

A spring-damper system consisting of at Least a differential cylinder (4), a hydraulic accumulator (26) and a control valve device (1, 2), is characterized in that by means of 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 dosed circuit using the control valve device (1, 2).

The present disclosure belongs to the technical field of two-wheel vehicles. A two-wheel automatic balance reset mechanism comprises a balance bar arranged between a frame and each front wheel support, the balance bar comprises a piston cylinder and a piston rod, the piston rod is movably arranged in a piston chamber of the piston cylinder, two ends of the piston chamber are mutually interconnected to form a first channel, a main control valve is arranged on the first channel and divides the first channel into a medium intake end and a backflow end, a medium tank is arranged at the backflow end, a pump is arranged at the medium intake end, and the pump is interconnected with the medium tank. A system comprises a main control module and an acquisition module, and the acquisition module comprises a balance sensor arranged on the frame and a speed sensor.

A motor vehicle chassis is provided having a base structure that can be hydraulically adjusted in level between a raised and a lowered position. A hydraulic adjuster is assigned to one of the two foot points of the corresponding suspension spring in each of the four wheel suspensions. At least two of the adjusters can be pressurized in parallel by a common hydraulic aggregate comprising a tank and a motor-pump unit and activated by a control unit. The at least two hydraulic adjusters that can be pressurized by the common hydraulic aggregate communicate hydraulically with the accumulator chamber of a spring-piston accumulator, which has at least one piston-position transmitter linked by signal transmission to the control unit.