A shock absorber includes: a shock absorber main body that has an outer tube and a rod movably inserted into the outer tube and can extend and contract; a main passage and a sub passage that communicate in parallel two working chambers provided in the shock absorber main body; a main damping force generation element provided in the main passage; and a sub damping force generation element provided in the sub passage. The main damping force generation element has only a main valve that opens and closes the main passage. The sub damping force generation element has an orifice provided in series with the sub passage, and a sub valve that opens and closes the sub passage and has a valve opening pressure lower than that of the main valve.

A piston housing unit comprises a housing with a longitudinal axis, a piston rod that is displaceable, in particular along the and/or around the longitudinal axis, a guide/damping unit for guiding and damping the displacement of the piston rod.

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.

Providing a sealing member which can successfully scrape off foreign substances and prevent failure caused by incorporation of foreign substances. A dust seal serving as a sealing member includes a dust seal body and a lip member. The dust seal body has a predetermined elasticity and is retained in an opening of an outer tube into which an inner tube reciprocated in a projected state is inserted. The lip member is harder than the dust seal body and is attached to a distal end of the dust seal body. The lip member has a distal end which is brought into sliding contact with an outer peripheral surface of the inner tube.

A rod guide includes a housing portion and a depressed portion formed toward an outer periphery from a starting point located apart from a piston rod by ½ or more of a distance in an axial direction between a bottom surface of the housing portion and a flat portion of an oil seal in a radial direction closest to the piston rod, and a bush is disposed to be flush with the bottom surface or disposed to project.

A dynamic balance type vertical vibration isolator includes slide blocks, balance springs, mass blocks, a fixed block, rotation shafts, stiffness-adjustable springs, etc. When an earthquake force is upward, the stiffness-adjustable springs are compressed, upward forces of the stiffness-adjustable springs are increased, meanwhile, the slide blocks and the mass blocks move away from the fixed block, the balance springs are stretched to generate pull forces, and the pull forces have vertically upward components, so as to reduce compression degrees of the stiffness-adjustable springs, and further to reduce the upward forces of the stiffness-adjustable springs. Similarly, when the earthquake force is downward, the stiffness-adjustable springs are stretched, downward forces of the stiffness-adjustable springs are increased, meanwhile, the slide blocks and the mass blocks move close to the fixed block, the balance springs are compressed to generate compression forces, and the compression forces have vertical downward components.

Shock absorption assemblies are provided. A shock absorption assembly includes an air shock that has a valve body. An air spring tube defines an air spring chamber. A piston rod extends through the air spring chamber to an oil piston head. An air piston head movably coupled to the piston rod. An oil damper tube is coupled to the piston head and is movable relative to the piston rod and the air spring tube. The shock absorption assembly further includes a mechanical spring disposed radially outward from, and that annularly surrounds, at least a portion of the air shock.

A movement control device comprising a housing with an elongate push rod mounted therein for reciprocal movement along a longitudinal axis between first and second positions, wherein the push rod extends out of said housing in both the first and second positions. A spring comprising a primary axis operable to provide a biasing force on the push rod is further provided in the housing. A damping device comprising a primary axis is located in the housing, wherein the damping device is in continuous engagement with the push rod through its reciprocating movement. The primary axis of the spring and the primary axis of the damping device are not coaxial.

A head unit system for controlling an object includes a secondary object sensor and a head unit device that include shear thickening fluid (STF) and a chamber configured to contain the STF. The chamber further includes a front channel and a back channel. The head unit device further includes a piston housed at least partially radially within the piston compartment and separating the back channel and the front channel. The piston includes a first piston bypass and a second piston bypasses to control flow of the STF between opposite sides of the piston. The chamber further includes a set of fluid flow sensors and a set of fluid manipulation emitters to control the flow of the STF to cause selection of one of a variety of shear rates for the STF within the chamber to control motion of the object with regards to a secondary object.

Solar tracker systems include a torque tube, a solar panel attached to the torque tube, and a damper assembly. The damper assembly includes an outer shell, a first chamber wall and a second chamber wall within the outer shell at least partially defining a chamber, and a piston to direct fluid through the chamber. A valve is within the chamber that includes a first axial end, a second axial end, and a seal positioned on the first axial end. The damper assembly further includes a biasing assembly that biases the valve into a first position within the chamber in which the seal is spaced from the first chamber wall. The valve is moveable within the chamber from the first position to a second position in which the seal contacts and seals against the first chamber wall to prevent the flow of fluid through the chamber.