A shock absorber includes: a bottomed cylindrical outer tube that is disposed so as to cover an inner case, and that is formed of a resin and is closed at one end by a closing part; a joint member that is embedded by insert molding in an opening end of the outer tube; and a coupling member that is coupled to the joint member.

A hydraulic damping cylinder for a prosthetic knee joint, including a housing, a cylinder chamber in the housing and filled with a hydraulic fluid, and a piston arranged in the cylinder chamber and movable by a piston rod. In the housing there are provided at least two separate receiving chambers, which are of different size and are connected to the cylinder chamber by fluid ducts, for hydraulic fluid displaced from the cylinder chamber during a piston movement. The receiving chambers are each separated, by a diaphragm, from a compression chamber filled with a compressible fluid that forms an energy store. Upstream of the larger receiving chamber, there is connected a throttle device which forms a flow resistance for the hydraulic fluid flowing into the receiving chamber so that the hydraulic fluid can be distributed to the two receiving chambers in a manner dependent on speed of the piston movement.

In a shock absorber 100, 200, an inner case 1 is biased in the axial direction relative to an outer case 2 made of resin by a spring 5, and the inner case 1 and the outer case 2 abut each other in the radial direction via ribs 2g, 8c.

A damper assembly includes an outer cylinder, an inner cylinder positioned at least partially within the outer cylinder, a cap coupled to the inner cylinder, and a plunger positioned radially inward from the inner cylinder and coupled to a rod. The plunger, the cap, and an interior of the inner cylinder at least partially define a first chamber. The suspension system further includes a passage extending through the rod and fluidly coupled with the first chamber, a piston coupled to the inner cylinder and extending radially outward toward the outer cylinder, a first port in fluid communication with the plunger through the passage, and a second port in fluid communication with the piston. The piston, an exterior surface of the inner cylinder, and the outer cylinder at least partially define a second chamber.

The hydraulic damping device includes: a cylinder storing fluid; a piston configured to form a channel through which the fluid flows along with relative movement of a rod relative to the cylinder in a specific direction; a valve having elasticity, the valve being configured to open and close the channel in the piston; a movement permitting part configured to permit the valve to move between a contact position and a spaced position, the contact position being a position where the valve contacts the piston, the spaced position being a position where the valve is spaced from the piston; a restricting part configured to restrict bending of the valve at the spaced position; and an imparting part having elasticity, the imparting part being configured to impart, to the valve, a load that is uneven in a circumferential direction of the valve and directed toward the piston.

In a suspension device, a first piston is movable in an axial direction inside of a cylinder, and an inner pipe that extends in the axial direction is provided inside of the cylinder. A first rod is coupled to the first piston and inserted into the inner pipe. A second rod is coupled to the first piston and projects outwardly from the cylinder. A second piston is movable in the axial direction while sealing a space between an outer surface of the inner pipe and an inner surface of the cylinder. A first gas chamber is located between the second piston and a closure to be arranged outside of the inner pipe. A second gas chamber is located inside of the inner pipe. The first rod includes a first inner passage that communicates with the second gas chamber, and the second rod includes a second inner passage that communicates with the first inner passage.

A damper assembly includes a tubular member including a sidewall and a shoulder. The damper assembly includes a rod and a piston coupled to the rod. A secondary piston has a second contact surface, an opposing second surface, an inner cylindrical face defining a central aperture that receives the rod, and an outer cylindrical face. The opposing second surface includes one or more surface grooves, extending between the inner cylindrical face and the outer cylindrical face along the opposing second surface, and one or more bypass orifices disposed about the body member. The bypass orifices extend along the inner cylindrical face between the second contact surface and the opposing second surface. The secondary piston defines a channel extending between the inner cylindrical face and an outer periphery of the body member. The channel and bypass orifices form a fluid flow path when the piston contacts the secondary piston.

A bearing spring/damper system of a vehicle wheel has a hydraulic vibration damper consisting of a damper cylinder and a damper piston guided therein, the piston rod of which hydraulic vibration damper is fastened to the vehicle body, whilst the damper cylinder is supported to a wheel guiding element. A pretension spring is clamped functionally between the damper piston and a pretension piston which can be displaced hydraulically in the longitudinal direction of the piston rod. The pretension piston is supported hydraulically with respect to the damper cylinder by a support chamber filled with the hydraulic medium of the vibration damper, and can be displaced by a conveying device, which conveys hydraulic medium into or out of the support chamber. The pretension spring is parallel-connected in every possible position of the pretension piston of a bearing spring ultimately clamped between the vehicle body and the wheel for force transmission.

A damper assembly comprises a main tube extending along a center axis between a first end and a second end defining a fluid chamber. A main piston is disposed in the fluid chamber dividing the fluid chamber into a compression chamber and a rebound chamber. A piston rod extends along the center axis coupled to the main piston. An external tube extends about the main tube and defines a compensation chamber therebetween. The external tube includes a protrusion extending radially inwardly from an opened end to abut the main tube. An external piston is located in the compensation chamber and coupled to the main tube, dividing the compensation chamber into a first compartment and a second compartment. The first compartment extends between the protrusion and the external piston for containing a working fluid. The second compartment extends between the closed end and the external piston for containing a gas.

A method for monitoring a dual-stage, separated gas/fluid shock strut includes receiving, by a controller, primary chamber temperature and pressure sensor readings, secondary chamber pressure and temperature sensor readings, and a shock strut stroke sensor reading, determining, by the controller, a shock strut stroke at which a secondary chamber is activated, calculating, by the controller, a volume of oil in an oil chamber of the shock strut, a primary chamber gas volume of, a number of moles of gas in, and a volume of oil leaked into, a primary gas chamber of the shock strut, a secondary chamber gas volume in, a volume of oil leaked into, and a number of moles of gas in, the secondary chamber, based upon at least one of the secondary chamber pressure sensor reading, and the secondary chamber temperature sensor reading.