A damper assembly comprises a monotube damper and a twintube damper in a telescopic configuration. A first piston is connected to a rod and is slidably disposed within a first tube. A second tube and a third tube are each disposed coaxially around the monotube damper, with the third tube disposed within the second tube and defining an annular chamber therebetween. A second piston is connected to an axial end of the first tube dividing an interior of the third tube into an upper chamber and a lower chamber. The second piston defines a twintube passage providing fluid communication therethrough. A base member defines a base passage providing fluid communication between the lower chamber and the annular chamber. A seal selectively blocks fluid flow through the twintube passage or the base passage and based on an axial position of the first tube relative to the second tube.

This shock absorber has a first damping force characteristic that is exhibited when a piston speed is from a low-speed region to a high-speed region while a relative position of a piston with respect to a cylinder is in a first range during a low frequency, a second damping force characteristic greater than the first damping force characteristic is exhibited when the piston speed is from the low-speed region to the high-speed region while the relative position is in a second range different from the first range during a low frequency, and a difference in damping force characteristic between during the first range and during the second range is smaller than a difference between the first damping force characteristic and the second damping force characteristic during a high frequency. A second passage is provided with a variable orifice mechanism with a changeable orifice area based on relative position.

This shock absorber has a first damping force characteristic that is exhibited when a piston speed is from a low-speed region to a high-speed region while a relative position of a piston with respect to a cylinder is in a first range during a low frequency, a second damping force characteristic greater than the first damping force characteristic is exhibited when the piston speed is from the low-speed region to the high-speed region while the relative position is in a second range different from the first range during a low frequency, and a difference in damping force characteristic between during the first range and during the second range is smaller than a difference between the first damping force characteristic and the second damping force characteristic during a high frequency. A second passage is provided with a variable orifice mechanism with a changeable orifice area based on relative position.

A vibration damper for a vehicle, includes at least one cylinder tube forming a fluid chamber, in which a piston assembly is axially and slidingly arranged and divides the cylinder tube into two working chambers, an upper and a lower working chamber, and wherein the piston assembly has an axially moveable main piston which is axially fixed to a piston rod that can move axially relative to the cylinder tube, and which has a piston valve influencing the fluid flow between the upper and lower working chambers, and wherein a further stroke-dependent piston is arranged on an axial extension of the piston rod in the direction of the cylinder base, which operates once a determined damper stroke is achieved. The stroke-dependent piston has a smaller diameter than the main piston and only operates when plunging into a smaller diameter of an inner casing surface. The stroke-dependent piston therefore has a stroke-dependent valve, and the stroke-dependent piston also has a frequency-dependent valve in addition to the stroke-dependent valve.

A vibration damper for a vehicle, includes at least one cylinder tube forming a fluid chamber, in which a piston assembly is axially and slidingly arranged and divides the cylinder tube into two working chambers, an upper and a lower working chamber, and wherein the piston assembly has an axially moveable main piston which is axially fixed to a piston rod that can move axially relative to the cylinder tube, and which has a piston valve influencing the fluid flow between the upper and lower working chambers, and wherein a further stroke-dependent piston is arranged on an axial extension of the piston rod in the direction of the cylinder base, which operates once a determined damper stroke is achieved. The stroke-dependent piston has a smaller diameter than the main piston and only operates when plunging into a smaller diameter of an inner casing surface. The stroke-dependent piston therefore has a stroke-dependent valve, and the stroke-dependent piston also has a frequency-dependent valve in addition to the stroke-dependent valve.

An embodiment of the present disclosure relates to a shock absorber. A shock absorber which is divided into a compression chamber and a rebound chamber by a piston valve in a tube having an interior filled with a fluid includes a first elastic member disposed in the compression chamber, a second elastic member disposed in the compression chamber to be spaced apart from the first elastic member, and a mid-guide member disposed between the first elastic member and the second elastic member and movable along a longitudinal direction of the compression chamber.

A body weight adjustment mechanism for automatic adjustment to a balanced point is provided to improve vibration absorption characteristics and impact absorption characteristics. A torsion angle of a lower frame-side torsion bar when an upper frame is at a balanced point is found in advance, a torsion angle of the lower frame-side torsion bar in a state in which a person is seated is detected, the detected torsion angle is compared with the aforesaid balanced point torsion angle, a control signal is sent to an elastic force adjusting unit, and torsion angles of upper frame-side torsion bars are adjusted so that the torsion angle of the lower frame-side torsion bar becomes equal to the balanced point torsion angle. The upper frame can be set to an appropriate position in an initial state and a static state in which a person is seated and vibration and impact absorption characteristics are improved.

A method and apparatus for a damper. The damper comprises a fluid chamber having a piston dividing the chamber into a compression and rebound sides, a reservoir in fluid communication with the compression side of the chamber, and an isolator disposed between the compression side and the reservoir, whereby the isolator obstructs fluid flow between the compression side and the reservoir. In one embodiment, a bypass provides a fluid path between the compression side and the isolator.

A method and apparatus for a damper. The damper comprises a fluid chamber having a piston dividing the chamber into a compression and rebound sides, a reservoir in fluid communication with the compression side of the chamber, and an isolator disposed between the compression side and the reservoir, whereby the isolator obstructs fluid flow between the compression side and the reservoir. In one embodiment, a bypass provides a fluid path between the compression side and the isolator.

A damper assembly comprises a main tube defining a fluid chamber. The main tube includes a first section, a second section, and an intermediate portion. A sleeve is disposed about the main tube. An external tube is disposed about the main tube and the sleeve. The external tube defines a compensation chamber between the sleeve and the external tube. A main piston divides the fluid chamber into a rebound chamber and a compression chamber. A piston rod couples to the main piston for moving the main piston between a compression stroke and a rebound stroke. The sleeve is in an abutment relationship with the second section of the main tube, radially spaced apart from the first section of the main tube, defining a compartment extending between the sleeve and the first section of the main tube. A housing for the damper assembly is also disclosed herein.