Hydraulic shock absorber and cover member

A hydraulic shock absorber, comprising:

• a first cylinder containing a fluid;
• a second cylinder positioned outside the first cylinder and forming a fluid reserving chamber that reserves the fluid between the second cylinder and the first cylinder;
• a piston housed inside the first cylinder;
• a piston rod supporting the piston, a part of the piston rod protruding from the first cylinder;
• and
• a cover member covering one end of the first cylinder from which the piston rod protrudes, and having a through hole through which the piston rod penetrates,
• wherein at least a part of the cover member in a circumferential direction of the first cylinder is apart from the first cylinder to form an opening through which the fluid flows from inside of the first cylinder to the fluid reserving chamber,
• the cover member includes a fluid supply unit that supplies the fluid to a gap between an inner circumferential surface of the through hole and an outer circumferential surface of the piston rod,
• the fluid supply unit includes, in the gap, a flow forming passage that forms a flow of the fluid from inside to outside of the first cylinder along an axial direction of the first cylinder, and
• one end of the flow forming passage communicates with the gap and the other end of the flow forming passage is located closer to the opening than the gap.