| 摘要 |
PROBLEM TO BE SOLVED: To form a pressure buffer device which changes a damping force generated thereby with a simple structure.SOLUTION: A hydraulic shock absorber 1 includes: a cylinder 11; a piston ring 44 which divides a space in the cylinder 11 into a first oil chamber Y1 and a second oil chamber Y2; a first valve seat 41 forming an expansion side oil passage 411; an expansion side damping valve 42 which opens or closes the expansion side oil passage 411 of the first valve seat 41; a second valve seat 51 which forms an inner passage 511 in which an oil flows separately from an oil flow used by the expansion side damping valve 42 to open the expansion side oil passage 411; a second valve 52 which opens and closes the inner passage 511; a spool 62 which is provided so as to move contacting with the second valve 52 and presses the second valve 52 toward the inner passage 511; a base member 61 which holds the spool 62; and a free piston 64 which forms a back pressure chamber 60C, which communicates with the inner passage 511 and stores the oil, between the spool 62 and the base member 61 and is provided so as to move relative to the spool 62 and the base member 61 in an axial direction.SELECTED DRAWING: Figure 2 |
