Hydraulic shock absorber and method for manufacturing same

A front fork comprising:

• an inner tube formed in a tubular shape and having an oil flowing therein;
• a damper cylinder that is a tube body provided inside the inner tube body and configured to relatively move along an axis of the inner tube, the damper cylinder having the oil flowing therein, and having the oil flowing in an oil passage formed between the inner tube and the damper cylinder;
• a fixed partition member fixed to an inner periphery of the damper cylinder and partitioning one end of an oil chamber;
• a rod extending along an axial direction of the damper cylinder through the fixed partition member, being supported by a support member that supports one end of the inner tube, and being configured to move relative to the fixed partition member, an outer periphery of the rod having a plurality of dimple portions that are formed in a staggered manner, each of the dimple portions being formed in an elongated shape along a circumferential direction of the rod and recessed toward a center of the rod, a boundary between each of the dimple portions and an outer peripheral surface of the rod being formed in cross section by a curved surface;
• and
• a piston provided at a distal end of the rod and allowing the oil to pass.

A front fork comprising:

• an outer tube formed in a tubular shape and having an oil flowing therein;
• a damper cylinder that is a tube body provided inside the outer tube and having one end fixed to one end of the outer tube, the damper cylinder having the oil flowing therein, and having the oil flowing in an oil passage formed between the outer tube and the damper cylinder;
• a movable partition member provided on an inner periphery of the damper cylinder in a movable manner and partitioning one end of an oil chamber;
• a rod extending along an axial direction of the damper cylinder through the movable partition member, being supported by a fork bolt that closes one end of the damper cylinder, and being configured to move relative to the movable partition member, an outer periphery of the rod having a plurality of dimple portions that are formed in a staggered manner, each of the dimple portions being formed in an elongated shape along a circumferential direction of the rod and recessed toward a center of the rod, a boundary between each of the dimple portions and an outer peripheral surface of the rod being formed in cross section by a curved surface;
• and
• a piston provided at a distal end of the rod and allowing the oil to pass.