Shock absorber

A shock absorber comprising:

• a cylinder;
• a piston rod inserted into the cylinder so as to be movable in an axial direction;
• a piston connected to the piston rod, and inserted into the cylinder so as to movable in the axial direction to partition the inside of the cylinder into an extension side chamber and a compression side chamber filled with liquid;
• an outer tube covering an outer circumference of the cylinder to form a reservoir between the outer tube and the cylinder;
• an extension side main valve giving resistance to a flow of liquid from the extension side chamber toward the compression side chamber;
• a compression side main valve and a compression side sub valve provided in series between the compression side chamber and the reservoir, and giving resistance to a flow of liquid from the compression side chamber toward the reservoir;
• an extension side sub valve provided between the reservoir and the compression side chamber, and giving resistance to a flow of liquid from the reservoir toward the compression side chamber;
• and
• a suction check valve provided in series with the extension side sub valve between the reservoir and the compression side chamber, and allowing only a flow of liquid from the reservoir toward the compression side chamber,
• wherein a damping force is generated only by the extension side sub valve when a piston speed is in a very low speed range during an extension operation, and
• a damping force is generated only by the compression side sub valve when a piston speed is in the very low speed range during a contraction operation.