| 摘要 |
PURPOSE:To generate a stable damping force with a simple piston main body by providing several types of expansion ports on the piston main body inserted into a cylinder and opening or closing the ports with large and small leaf valves formed on the lower end face of the piston main body. CONSTITUTION:The cylinder 1 of an hydraulic shock absorber is partitioned into the upper and lower chambers A, B by the piston main body 30 of a piston section 3 inserted into it. In this case, multiple expansion ports 30a allowing the inflow of operating oil from the upper chamber A to the piston main body 30 and multiple expansion ports 30b allowing the inflow of operating oil via a rotary valve 20 in a passage L formed on a piston rod 2 are formed. Multiple opening windows 30c, 30d, large and small, are formed on the lower end face of the piston main body 30, and the expansion ports 30b, 30a are opened on the opening windows 30c, 30d. Leaf valves 32a, 32b with large and small diameters are provided on the lower end face of the piston main body 30 to open or close the opening windows 30c, 30d. |
