Patent ID: 8672306

Claim:
A vehicle shock absorber comprising: a vehicle body side tube and an vehicle axle side tube forming a telescopic shock absorber; a cylinder which is provided in one of the vehicle body side tube and the vehicle axle side tube and one end thereof is attached to a bottom of the one of the tubes and axially extends, and a cap is mounted on the other end thereof; a rod which is provided in the other one of the vehicle body side tube and the vehicle axle side tube and one end thereof is attached to a bottom of the other tube and axially extends, and the other end slidably penetrates through the cap of the cylinder into the cylinder; a piston which is attached to the other end of the rod and slides in the cylinder with a contraction and elongation of a shock absorber body to generate a damping force by a flow resistance of oil in the cylinder; a suspension spring which energizes a spring holder fixed on the cylinder in an elongation direction of the shock absorber body; a first oil chamber which is formed outside the cylinder and acts as an oil reservoir in the shock absorber body; and a second oil chamber which is formed inside the cylinder, wherein the vehicle shock absorber further includes: a plurality of first oil communication holes axially provided side by side in a peripheral wall of the cylinder; a second oil communication hole; and a third oil chamber provided outside the cylinder and communicating with the second oil chamber via the plurality of first oil communication holes and the second communication hole, and wherein the plurality of first oil communication holes are sequentially closed according to a moving position of the piston in the cylinder during a contraction action of the shock absorber body and thereby a flow volume of a working oil from the cylinder gradually decreases; and wherein the vehicle shock absorber has a tubular member which is fixed to an outer circumference of the cylinder to form a double tube structure and a space between an inner circumference of the tubular member and the outer circumference of the cylinder is the third oil chamber.