A damping force adjustable shock absorber in2cludes an electromagnetic damping force adjustment device (17) having a damping force adjustment valve (18), and a solenoid (33) configured to variably adjust the damping force. The solenoid includes a coil (39) configured to generate a magnetic force by power supply, a movable iron core (43) located on an inner peripheral side of the coil, an anchor member (40) configured to attract the movable iron core. The movable iron core includes a thick cylindrical portion (43A) and a taper cylindrical portion (43B). The thick cylindrical portion includes a fixation hole (43A1) in which a shaft portion (44) is fixed. The taper cylindrical portion has an inner peripheral surface flaring so as to define a taper shape. A recessed portion (43A2) is formed around the fixation hole. The recessed portion allows hydraulic fluid to flow in an axial direction of the movable iron core.

A hydraulic damper including a tube defining a chamber. The tube has a main section and a narrowed section. A main piston assembly is disposed in the main section and connected to a piston rod. A resisting mechanism is fixed to the piston rod. A secondary piston is moveable into the narrowed section. An inner surface of the secondary piston defines at least one radially internal channel. The piston rod defines an annular recess. The secondary piston includes a locking mechanism axially slideable within the annular recess. The secondary piston is axially moveable between a hydraulic stop engagement stroke wherein the secondary piston engages the resisting mechanism and restricts the flow of fluid through the radially internal channel, and a hydraulic stop disengagement stroke wherein the secondary piston is spaced from the resisting mechanism and allows the flow of fluid through radially internal channel.

A hydraulic damper including a tube defining a chamber. The tube has a main section and a narrowed section. A main piston assembly is disposed in the main section and connected to a piston rod. A resisting mechanism is fixed to the piston rod. A secondary piston is moveable into the narrowed section. An inner surface of the secondary piston defines at least one radially internal channel. The piston rod defines an annular recess. The secondary piston includes a locking mechanism axially slideable within the annular recess. The secondary piston is axially moveable between a hydraulic stop engagement stroke wherein the secondary piston engages the resisting mechanism and restricts the flow of fluid through the radially internal channel, and a hydraulic stop disengagement stroke wherein the secondary piston is spaced from the resisting mechanism and allows the flow of fluid through radially internal channel.

A prosthetic joint and a method of controlling dorsiflexion and plantarflexion of the hydraulic prosthetic ankle joint. The method includes generating ground reaction forces with a hydraulic prosthetic ankle, wherein the prosthetic hydraulic ankle comprises a first chamber and a second chamber, and the ankle is connected to a prosthetic foot; rotating the prosthetic foot in response to the ground reaction force; transferring fluid between the forward and rear chambers in response to rotation of the foot; providing a feature to occlude or partially occlude the fluid transfer between chambers; providing a non-electronic mechanism for controlling the flow responsive to both a position of the joint and a rate of change of position of the joint, and wherein the mechanism is arranged such that a dwell at a particular joint location or locations will occlude the flow path.

A shock absorber is provided that includes a shock body and a shaft assembly. The shock body has an inner chamber. The inner chamber is defined by a cylindrical interior surface. At least one groove is formed in the interior surface within at least one select length of the shock body. A piston of the shaft assembly is received within the inner chamber of the shock body. The piston includes valving to allow dampening matter that is received within the inner chamber to pass through the piston to allow the piston to move within the inner chamber. The at least one groove that is formed within the interior surface is configured to allow at least some of the dampening matter to bypass the valving of the piston to allow the piston to move through the at least one select length with less resistance.

A shock absorber is provided that includes a shock body and a shaft assembly. The shock body has an inner chamber. The inner chamber is defined by a cylindrical interior surface. At least one groove is formed in the interior surface within at least one select length of the shock body. A piston of the shaft assembly is received within the inner chamber of the shock body. The piston includes valving to allow dampening matter that is received within the inner chamber to pass through the piston to allow the piston to move within the inner chamber. The at least one groove that is formed within the interior surface is configured to allow at least some of the dampening matter to bypass the valving of the piston to allow the piston to move through the at least one select length with less resistance.

Provided is a shock absorber that includes a middle chamber formed by a piston, a first damping-force generating device that is provided between an upper chamber and the middle chamber and generates a damping force, a second damping-force generating device that is provided between a lower chamber and the middle chamber and generates a damping force, and a position-based state changing device that changes a state of a passage to a state in which the upper chamber and the lower chamber communicate with each other, a state in which the upper chamber and the middle chamber communicate with each other, or a state in which the lower chamber and the middle chamber communicate with each other depending on a position of the piston.

A vibration damper for a vehicle may include an outer tube, a middle tube, and an inner tube arranged coaxially. A seal receiving element may be arranged between the inner tube and the middle tube on each side of a middle tube opening facing towards tube ends of the middle tube. A radially encircling sealing element may be arranged in the seal receiving element, and the sealing element may seal the middle tube compensation space relative to the outer tube compensation space at least with respect to damping medium. The seal receiving element may be configured at least partially as a coating element. The coating element may be disposed on the inner tube or the middle tube in a substance-to-substance bonded manner.

A vibration damper for a vehicle may include an outer tube, a middle tube, and an inner tube arranged coaxially. A seal receiving element may be arranged between the inner tube and the middle tube on each side of a middle tube opening facing towards tube ends of the middle tube. A radially encircling sealing element may be arranged in the seal receiving element, and the sealing element may seal the middle tube compensation space relative to the outer tube compensation space at least with respect to damping medium. The seal receiving element may be configured at least partially as a coating element. The coating element may be disposed on the inner tube or the middle tube in a substance-to-substance bonded manner.

A damping force adjustable shock absorber includes an electromagnetic damping force adjustment device (17) having a damping force adjustment valve (18), and a solenoid (33) configured to variably adjust the damping force. The solenoid includes a coil (39) configured to generate a magnetic force by power supply, a movable iron core (43) located on an inner peripheral side of the coil, an anchor member (40) configured to attract the movable iron core. The movable iron core includes a thick cylindrical portion (43A) and a taper cylindrical portion (43B). The thick cylindrical portion includes a fixation hole (43A1) in which a shaft portion (44) is fixed. The taper cylindrical portion has an inner peripheral surface flaring so as to define a taper shape. A recessed portion (43A2) is formed around the fixation hole. The recessed portion allows hydraulic fluid to flow in an axial direction of the movable iron core.