A method and apparatus for a shock absorber having a damping fluid compensation chamber with a gas charge. In one aspect, a partition separates a first chamber portion from a second chamber portion, wherein the first portion of the chamber is at a first initial gas pressure and the second portion of the chamber is at a second initial pressure. A valve separates the first and second chamber portions and opening the valve comingles the first and second chamber portions so that the combined chamber portions are at a third pressure. In another aspect, a piston disposed through a wall is in pressure communication with the gas charge and is biased inwardly toward a pressure of the charge, whereby an indicator is movable by the piston in response to the pressure.

To provide a solenoid, a solenoid valve, and a damper in which when the amount of current supplied to the solenoid is small, the thrust of the solenoid to bias an object in one direction can be made small, and at the same time, even when the solenoid is not energized, the object can be biased in the same direction as that of the thrust. The solenoid includes a coil, a first movable iron core and a second movable iron core that are attracted in a direction away from each other by energizing the coil, a coil spring that biases the first movable iron core toward the second movable iron core, and a leaf spring that restricts the approach of the first movable iron core and the second movable iron core.

A hydraulic shock-absorber comprises an outer cylindrical tube, an inner cylindrical tube defining with the outer cylindrical tube an annular chamber, a main piston slidably mounted in the inner cylindrical tube and dividing the inner volume of the inner cylindrical tube into an extension chamber and a compression chamber, both containing an incompressible damping fluid, a valve assembly mounted on a bottom wall of the inner cylindrical tube and comprising a first compression valve and a first intake valve, a cup-shaped body mounted in the inner cylindrical tube, inside the compression chamber, and an auxiliary piston rigidly connected to the main piston and configured to slide in the cup-shaped body at least during a final section of the compression phase of the shock-absorber. The shock-absorber further comprises a second compression valve configured as a non-return valve allowing the flow of the damping fluid only in the direction from a working chamber of the cup-shaped body towards a lower portion of the compression chamber.

A vehicle suspension system comprising a hydropneumatic strut comprising a fluid interface, where supply of hydraulic fluid to the strut via the fluid interface causes the overall length of the strut to increase, and withdrawal of hydraulic fluid via the fluid interface causes the overall length of the strut to decrease, a first displacement system in fluid communication with the fluid interface, capable of supplying and withdrawing fluid to and from the strut as well as measuring the volume of fluid supplied or withdrawn from the strut, a second displacement system in fluid communication with the fluid interface, and a hydraulic fluid source for selectively supplying or withdrawing hydraulic fluid from the hydropneumatic strut via either of the first or second displacement systems.

A suspension strut for a vehicle comprises: a first connector for connecting to a first point on the vehicle; a second connector for connecting to a second point on the vehicle; and a damper assembly adapted to provide a damping force as fluid flows through the damper assembly during relative compression between the first point and the second point, wherein the damper assembly comprises a side wall and a damper aperture in the side wall, wherein the damper aperture is open throughout operation of the strut to allow fluid to flow through the damper assembly.

The actuator comprises a cylinder and a rod. The cylinder comprises an inner cylindrical tube and an outer cylindrical tube which extend coaxially to each other along a longitudinal axis (z). The inner cylindrical tube accommodates a plunger which is rigidly connected to the rod and separates an inner volume of the inner cylindrical tube into a compression chamber and an extension chamber, wherein at least the compression chamber contains oil. The inner cylindrical tube and the outer cylindrical tube enclose with each other a reservoir chamber which is permanently in fluid communication with the extension chamber via at least one first passage provided in the inner cylindrical tube and contains a pressurized gas in a first portion thereof and oil in a remaining portion thereof. The cylinder further comprises an intermediate cylindrical tube which extends along the longitudinal axis (z) between the inner cylindrical tube and the outer cylindrical tube and encloses, along with the inner cylindrical tube, an intermediate chamber permanently in fluid communication with the compression chamber via at least one second passage provided in the inner cylindrical tube. The actuator further comprises a check valve associated to the inner cylindrical tube to allow the oil to flow in the direction from the reservoir chamber to the compression chamber only, and an electrically-operated flow control valve which is associated to the intermediate cylindrical tube for controlling the flow of the oil between the intermediate chamber and the reservoir chamber. The flow control valve is movable between a first operating position, in which it allows the oil to flow between the intermediate chamber and the reservoir chamber, and a second operating position, in which it prevents the oil from flowing between the intermediate chamber and the reservoir chamber.

In a suspension system in which the oil chambers of two dampers are connected, the responsiveness of the dampers can be adjusted. A suspension system has a left damper, a right damper, and an intermediate unit. A case of the intermediate unit has an intermediate oil chamber connected to an oil chamber of the left damper and the oil chamber of the right damper and an intermediate gas chamber. The intermediate oil chamber and the intermediate gas chamber are partitioned by a diaphragm. The intermediate unit has a capacity adjustment mechanism including a movable portion of which the position can be changed. The capacity adjustment mechanism adjusts the capacity of the intermediate gas chamber by changing the position of the movable portion.

The invention relates to a vibration damper for a motor vehicle comprising an inner tube, an outer tube and at least one compensating chamber, which is formed between the inner tube and the outer tube and comprises at least one gas bag, which is arranged in the compensating chamber, wherein the compensating chamber is fluidically connected to at least one working area of the inner tube filled with a hydraulic fluid, wherein at least one guide element is provided, which deflects a flow of the hydraulic fluid during a rebound stage or a compression stage in such a way that the gas bag is indirectly subjected to flow. Furthermore, the invention relates to a motor vehicle.

An adjustable vibration damper for a vehicle may include an outer tube, an intermediate tube, and an inner tube arranged coaxially. A concentric compensation chamber between the outer tube and the intermediate tube may receive a hydraulic fluid and a gas. A piston rod may include a piston disposed movably in the inner tube and dividing an interior of the inner tube into first and second working chambers. The adjustable vibration damper may also include first and second damper valves arranged on an outer wall. The first working chamber may be fluidically connected to the compensation chamber by the first damper valve for adjustment of a pressure stage, and the second working chamber may be fluidically connected to the compensation chamber by the second damper valve for adjustment of a traction stage.

A shock absorber includes: a first passage through which a working fluid flows from a chamber inside a cylinder; a second passage which communicates with the chamber; a damping force generation mechanism which is provided in the first passage, a communication hole which is provided with at least a part of a passage of the second passage and is formed in a piston rod communicating with at least the chamber; a housing which has a passage of least a part of the second passage; a free piston which is movably provided inside the housing and defines the second passage into an upstream side and a downstream side of a flow of the working fluid when the piston moves in one direction, and an elastic body which is provided between the free piston and the housing. The free piston is formed of a resin material.