Present disclosure A hydraulic stopping damper includes a cylinder in which a work fluid is stored, a piston rod coupled such that one side of the piston rod is to be inserted into an inner space of the cylinder, and a rod guide through which the piston rod passes and coupled to one side of the cylinder. The hydraulic stopping damper includes a rebound spring surrounding the piston rod and disposed in an inner space of the cylinder, and a shock mitigator between the rod guide and the rebound spring, the shock mitigator configured to generate a damping force by a hydraulic pressure of the work fluid when one side of the rebound spring compressed in response to a rebound stroke of the piston rod is inserted into the rod guide.

Disclosed herein is a hydraulic jounce bouncer comprising a damper body, a shaft telescopically engaged with the damper body, a piston slidably disposed within the damper body and threadedly coupled to a first end of the shaft, wherein the piston has at least one compression port therethrough, and a negative spring disposed between the shaft and the damper body.

A hydraulic damper comprises a main tube, a piston assembly, a base valve assembly, and a compression stop assembly. The compression stop assembly includes an insert defining an inner chamber, and a sleeve displaceable along with the main piston assembly and configured to be slidably introduced inside the inner chamber. The sleeve has a diameter lower than the diameter of the main tube defining a first external flow channel between the sleeve and the main tube; the sleeve is attached to the piston assembly by a spring disposed within the sleeve; and the insert is provided with a plurality of axially-spaced holes and has an annular flange adjoining the inner wall of the main tube and separating the compression chamber from a second external flow channel between the radially external outlets of the holes and the base valve assembly.

A linear actuator comprising a housing with first and second ends, and defining a central cavity extending axially therethrough; a tube having first and second portions, the first portion arranged to slide within the central cavity of the housing, and the second portion extending outwardly from the second end of the housing; a first elongated rotatable screw positioned axially within the central cavity and coaxial with the tube; a first nut mounted about the first elongated rotatable screw and configured to move axially as the first elongated rotatable screw rotates; a second elongated rotatable screw positioned axially within the central cavity; a second nut mounted about the second elongated rotatable screw and configured to move axially within the central cavity as the second elongated rotatable screw rotates; and a spring positioned around the second elongated rotatable screw between the second nut and the second end of the housing.

A shock absorber includes a suction passage permitting flow only from a reservoir toward a compression-side chamber, a rectification passage permitting flow only from the compression-side chamber toward an extension-side chamber, and a variable valve permitting flow only from the extension-side chamber toward the reservoir. A large chamber as a compression-side pressure chamber communicating with the compression-side chamber and an outer periphery chamber as an extension-side pressure chamber communicating with the extension-side chamber are partitioned in the shock absorber by a free piston that moves slidably within a bottom member serving as a housing. A compression-side pressure-receiving area of the free piston is larger than an extension-side pressure-receiving area. Therefore, even in the uniflow shock absorber with the extension-side chamber and the compression-side chamber at equal pressures during the contraction operation, the damping force is reduced under conditions in which high frequency is input since the free piston moves downward.

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 vehicle height adjustment apparatus according to one embodiment include a spring, a spring-length changing unit, a first valve, a control valve and a second valve. The spring-length changing unit changes a length of the spring in accordance with an amount of oil in a jack chamber that accommodates the oil. The first valve opens and closes a first communication path in which the oil supplied from a pump is oriented toward a reservoir chamber that stores the oil. The control valve opens and closes a discharge flow path oriented toward the reservoir chamber from a chamber that accommodates the oil to close the first valve. The second valve opens and closes a second communication path in which the oil supplied from the pump is oriented toward the jack chamber when the first valve is closed.

A shock absorber includes at least one of an expansion-side sensitive unit and a contraction-side sensitive unit. The expansion-side sensitive unit has an expansion-side actuating chamber that communicates with an expansion-side chamber and a contraction-side chamber, an expansion-side free piston that partitions the expansion-side actuating chamber into a first expansion-side pressure chamber and a second expansion-side pressure chamber, and an expansion-side spring element configured to bias the expansion-side free piston to compress the first expansion-side pressure chamber. The contraction-side sensitive unit has a contraction-side actuating chamber that communicates with a contraction-side chamber and a reservoir, a contraction-side free piston that partitions the contraction-side actuating chamber into a first contraction-side pressure chamber and a second contraction-side pressure chamber, and a contraction-side spring element configured to bias the contraction-side free piston to compress the first contraction-side pressure chamber.

A damper for a rotor hub for a rotorcraft can include a housing, a piston resiliently coupled to the housing with a first elastomeric member and a second elastomeric member, a plurality of conical members, a fluid, and an orifice.

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.