A rotary damper comprising a fixed structure, a rotor configured to rotate about an axis (R-R), and two opposing bellows. The bellows each extend between the rotor and the fixed structure and are attached thereto. The bellows each define a chamber for holding hydraulic fluid and are configured to expand and contract as the rotor rotates. The damper further comprises a damping orifice extending through the rotor or the fixed structure. The bellows are sealingly engaged around the damping orifice and the damping orifice permits fluid communication between the chambers defined by the bellows.

An air spring assembly having pressure relief capability, where the air spring assembly includes a single air volume, or a multi-chamber air volume. When the air spring assembly is operating at a stiffer spring rate in combination with a setting to increase ground clearance, during certain road events, the air spring assembly is compressed, and the pressure in the air spring assembly increases. In order to not exceed the safe mechanical limits of the air spring assembly, the pressure is limited to a maximum value when full compression is achieved. The air spring assembly includes at least one valve, which is opened based on a cracking pressure, which is determined based on the mechanical limits of the air spring assembly. This facilitates the operation of the air spring assembly at settings to increase ground clearance of the vehicle, while allowing for pressure relief when the mechanical limit is reached.

A damper includes a first passage and a second passage in parallel, a first damping force generation mechanism of the first passage, a case member in which a portion of the second passage is formed, an annular disc disposed to face a bottom part in the case member to be able to be bent by a working fluid in the case member, a first chamber communicating with a first cylinder chamber and a second chamber communicating with a second cylinder chamber which are provided by the disc partitioning the inside of the case member, a first through hole provided in the bottom part of the case member to communicate with the second chamber, a bypass passage provided in parallel to the first through hole and configured to allow communication between the first chamber and the second cylinder chamber, and a second damping force generation mechanism provided in the bypass passage.

An industrial gas spring with a pressure chamber in a casing with an end wall, a piston rod received at least in part in the casing for reciprocation between extended and retracted positions and a pressure relief assembly carried by the end wall. The pressure relief assembly may have a membrane communicating with the pressure chamber and a plunger configured to breach the membrane when engaged and moved by the piston rod when it overtravels its design intended retracted position.

In accordance with one aspect of the present disclosure, a suspension strut for use on a work machine is provided. The suspension strut may have a forged one piece cylindrical inner housing that includes a hollow rod which forms a circumferential piston at an open end and a lower clevis at a closed end of the hollow rod. The suspension strut may further have a forged one piece cylindrical outer housing that includes a hollow barrel having an interior and an exterior surface, a closed end that forms an upper clevis, an open end, and a port on an outside surface of the hollow barrel. Further, the inner and outer housing may be coupled by a disk shaped end cap attached to the open end of the hollow barrel having an inner diameter that is slideably engaged with an outer surface of hollow rod.

A shock absorber according to the present invention includes a shock absorber main body in which an internal air pressure is set to a pressure exceeding an atmospheric pressure, a relief valve configured to open when the air pressure in an air chamber of the shock absorber main body reaches a valve opening pressure, and a lock device capable of maintaining the relief valve in a closed state, and the air pressure in the shock absorber main body can be adjusted to the valve opening pressure of the relief valve.

A method for servicing a dual-stage, separated gas/fluid shock strut may comprise measuring a servicing temperature, charging a secondary gas chamber with compressed gas, wherein a secondary chamber pressure corresponds to the servicing temperature, pumping oil into the shock strut, and charging a primary gas chamber with compressed gas.

An industrial gas spring with a pressure chamber in a casing with an end wall, a piston rod received at least in part in the casing for reciprocation between extended and retracted positions and a pressure relief assembly carried by the end wall. The pressure relief assembly may have a membrane communicating with the pressure chamber and a plunger configured to breach the membrane when engaged and moved by the piston rod when it overtravels its design intended retracted position.

An air spring includes: an upper surface plate; a lower surface plate opposing the upper surface plate; an elastic film airtightly coupling a peripheral portion of the upper surface plate and a peripheral portion of the lower surface plate to each other to form an air chamber inside the air spring; the air chamber connected to the lower surface plate; and an exhaust passage forming body at which an exhaust passage is formed. The exhaust passage includes an exhaust passage inlet and an exhaust passage outlet. The exhaust passage inlet is open to an outside of the air chamber when a clearance between the upper surface plate and the lower surface plate in an upward/downward direction falls within a predetermined allowable range and is open to an inside of the air chamber when the clearance exceeds an upper limit of the predetermined allowable range.

Included are: a first supporting member; a second supporting member arranged to be spaced away from the first supporting member in a main load direction; an elastically deformable diaphragm forming a closed space by connecting the first supporting member and the second supporting member; a detection unit detecting a change of a relative distance between the first supporting member and the second supporting member, and producing a mechanical output of the change of the relative distance; and a controlling member capable of discharging air in an inside of the closed space S to an outside of the closed space S in response to the mechanical output from the detection unit. Thereby, an air spring having a mechanism for suppressing an abnormal rise of a vehicle height without deteriorating the diaphragm can be provided.