A damper assembly includes a pressure tube defining a first chamber and a piston movable within the first chamber. The damper assembly includes a reserve tube defining a second chamber. The damper assembly includes a cylinder end attached to the pressure tube, the cylinder end defining a passage in fluid communication with the first chamber and the second chamber. The damper assembly includes an orifice disc attached to the cylinder end and defining an opening in fluid communication with the passage. The damper assembly includes a check disc attached to the cylinder end, the check disc movable from a first position spaced from orifice disc to a second position abutting the orifice disc. Movement of the piston within the first chamber causes fluid flow between the first chamber and the second chamber via the passage of the cylinder end. The check disc and the orifice disc limit a rate of such fluid flow.

The present disclosure relates to a vibration control device and a frequency-sensitive shock absorber having the same. A vibration control device includes a sub-piston rod coupled to an end of a piston rod, a pilot valve unit penetrated by and coupled to the sub-piston rod, in which pressure is formed by a fluid introduced through the sub-piston rod, and a fixing member located in a lower portion of the pilot valve unit and fastened to the sub-piston rod to fix the pilot valve unit, wherein the pilot valve unit comprises a free-piston provided to reciprocate in a vertical direction according to a change in the pressure formed by the fluid.

A head unit system for controlling motion of an object includes an environment sensor and a head unit device that include shear thickening fluid (STF) and a chamber configured to contain the STF. The chamber further includes front and back channels. 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 abate an external factor of concern associated with an external environment as sensed by the environment sensor.

A head unit system for controlling motion of 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.

A solar tracker system includes a torque tube, a solar panel assembly attached to the torque tube, a housing defining a chamber and a fluid passageway extending from the chamber, and an active lock connected to a seal configured to prevent a flow path of fluid while in a sealed state and allow the flow path of fluid in an unsealed state. The system further includes a controller in communication with the torque tube and the active lock. The controller is programmed to receive a command to place the solar panel assembly in a stowed position, instruct the torque tube to rotate the panel assembly to a stowed angle corresponding to the stowed position, monitor a current angle of the panel assembly, compare the current angle to the stowed angle, and instruct the seal to transition to the sealed state when the current angle is equal to the stowed angle.

Solar tracker systems include a torque tube, a column supporting the torque tube, a solar panel attached to the torque tube, and a damper assembly. The damper assembly includes an outer shell surrounding an inner shell. A piston is at least partially positioned within the inner shell and moveable relative thereto. An active lock of the damper assembly includes a housing positioned within the outer shell. The housing defines a cavity and a housing channel extending from the cavity to an outer fluid channel. A shaft extends into the cavity and a valve assembly is attached to the shaft. The shaft is rotatable within the cavity between an unsealed position in which the housing channel is in fluid communication with the cavity, and a sealed position in which the valve assembly is rotationally aligned with the housing channel and obstructs fluid communication between the cavity and the housing channel.

Solar tracker systems include a torque tube, a column supporting the torque tube, a solar panel attached to the torque tube, and a damper assembly. The damper assembly includes an outer shell surrounding an inner shell. A piston is at least partially positioned within the inner shell and moveable relative thereto. An active lock of the damper assembly includes a housing positioned within the outer shell. The housing defines a cavity and a housing channel extending from the cavity to an outer fluid channel. A shaft extends into the cavity and a valve assembly is attached to the shaft. The shaft is rotatable within the cavity between an unsealed position in which the housing channel is in fluid communication with the cavity, and a sealed position in which the valve assembly is rotationally aligned with the housing channel and obstructs fluid communication between the cavity and the housing channel.

A damper assembly includes a pressure tube defining a first chamber and a piston movable within the first chamber. The damper assembly includes a reserve tube defining a second chamber. The damper assembly includes a cylinder end attached to the pressure tube, the cylinder end defining a passage in fluid communication with the first chamber and the second chamber. The damper assembly includes an orifice disc attached to the cylinder end and defining an opening in fluid communication with the passage. The damper assembly includes a check disc attached to the cylinder end, the check disc movable from a first position spaced from orifice disc to a second position abutting the orifice disc. Movement of the piston within the first chamber causes fluid flow between the first chamber and the second chamber via the passage of the cylinder end. The check disc and the orifice disc limit a rate of such fluid flow.

A shock absorber includes: a cylinder; a piston slidably inserted into the cylinder; a piston rod connected to the piston and extending outside the cylinder; a main valve that generates a damping force; a pilot chamber that applies pressure to the main valve; an introduction passage that introduces the fluid into the pilot chamber; a pilot passage that communicates the pilot chamber and a downstream side of the main valve with each other; and a control valve provided in the pilot passage. In an upstream side of the pilot passage from the control valve, the pilot passage is provided with a first orifice, a first passage provided in parallel with the first orifice, a first check valve that is opened at a predetermined differential pressure and allows a flow toward the control valve through the first passage, and a second orifice.

A hydraulic shock-absorber comprises an outer cylindrical tube, an inner cylindrical tube defining with the outer cylindrical tube an annular chamber, a main piston slidably mounted in the inner cylindrical tube and dividing the inner volume of the inner cylindrical tube into an extension chamber and a compression chamber, both containing an incompressible damping fluid, a valve assembly mounted on a bottom wall of the inner cylindrical tube and comprising a first compression valve and a first intake valve, a cup-shaped body mounted in the inner cylindrical tube, inside the compression chamber, and an auxiliary piston rigidly connected to the main piston and configured to slide in the cup-shaped body at least during a final section of the compression phase of the shock-absorber. The shock-absorber further comprises a second compression valve configured as a non-return valve allowing the flow of the damping fluid only in the direction from a working chamber of the cup-shaped body towards a lower portion of the compression chamber.