US 12,222,018 B2
Shock absorber
Kazuya Yamada, Hitachinaka (JP); Kentaro Yamada, Hitachinaka (JP); Reiji Nakagawa, Hitachinaka (JP); Hiroyasu Sato, Hitachinaka (JP); Sadatomo Matsumura, Hitachinaka (JP); and Wataru Takagi, Hitachinaka (JP)
Assigned to HITACHI ASTEMO, LTD., Ibaraki (JP)
Appl. No. 17/640,857
Filed by Hitachi Astemo, Ltd., Ibaraki (JP)
PCT Filed Sep. 25, 2020, PCT No. PCT/JP2020/036315
§ 371(c)(1), (2) Date Mar. 7, 2022,
PCT Pub. No. WO2021/065729, PCT Pub. Date Apr. 8, 2021.
Claims priority of application No. 2019-182405 (JP), filed on Oct. 2, 2019.
Prior Publication US 2022/0275847 A1, Sep. 1, 2022
Int. Cl. F16F 9/32 (2006.01); B60G 13/08 (2006.01); F16F 9/18 (2006.01)
CPC F16F 9/3214 (2013.01) [F16F 9/185 (2013.01); B60G 13/08 (2013.01); B60G 2202/24 (2013.01); B60G 2206/41 (2013.01); B60G 2800/162 (2013.01); F16F 2222/12 (2013.01); F16F 2230/30 (2013.01); F16F 2232/08 (2013.01); F16F 2234/02 (2013.01)] 11 Claims
OG exemplary drawing
 
1. A shock absorber comprising:
a bottomed cylinder-shaped cylinder in which a working fluid is enclosed;
a piston rod having a base end portion that is inserted into the cylinder, and a tip portion that protrudes out of the cylinder;
a piston that is fixed to a base end portion side of the piston rod and defines an inside of the cylinder into a one-side chamber and an other-side chamber; and
a rod guide provided on a side opposite to a bottom portion of the cylinder to guide the piston rod,
wherein the piston includes:
a piston main body that is fixed to the piston rod; and
a piston band that is provided on an outer peripheral portion of the piston main body and is in sliding contact with an inner peripheral portion of the cylinder,
wherein the piston main body has a stepped portion including a large-diameter surface portion, a stepped surface portion, and a small-diameter surface portion, at one end on a side close to the tip portion of the piston rod, of the outer peripheral portion on which the piston band is mounted,
wherein the piston band has, at an outer peripheral portion thereof, a large diameter portion that is formed on the side close to the tip portion of the piston rod, a medium diameter portion that is formed on a side far from the tip portion so as to have a smaller diameter than the large diameter portion, and a small diameter portion that is formed between the large diameter portion and the medium diameter portion so as to have a smaller diameter than the medium diameter portion, in a state before being disposed in the cylinder,
wherein, at the one end on the side close to the tip portion of the piston rod, an inner peripheral surface is inclined toward a piston main body side from the large-diameter surface portion to the small-diameter surface portion of the stepped portion,
wherein the inner peripheral surface at the one end of the piston band is separated from a stepped surface of the stepped portion, and
wherein at the one end of the piston band, both an inner peripheral surface end and an outer peripheral surface end are separated from the small-diameter surface portion.