US 11,898,615 B2
Cylinder apparatus
Toshihiro Inuzuka, Ebina (JP); Urban Anta Carlos, Schwaig-Oberding (DE); Atsushi Maeda, Fujisawa (JP); Koji Minamino, Fukushima (JP); and Aakash Patwa, Canton, MI (US)
Assigned to HITACHI ASTEMO, LTD., Ibaraki (JP)
Appl. No. 17/054,943
Filed by HITACHI ASTEMO, LTD., Hitachinaka (JP)
PCT Filed May 14, 2019, PCT No. PCT/JP2019/019046
§ 371(c)(1), (2) Date Nov. 12, 2020,
PCT Pub. No. WO2019/221098, PCT Pub. Date Nov. 21, 2019.
Claims priority of application No. 2018-094513 (JP), filed on May 16, 2018.
Prior Publication US 2021/0246961 A1, Aug. 12, 2021
Int. Cl. F16F 13/00 (2006.01); B60G 15/06 (2006.01); B60G 17/08 (2006.01)
CPC F16F 13/007 (2013.01) [B60G 15/061 (2013.01); B60G 17/08 (2013.01); B60G 2202/30 (2013.01); B60G 2204/62 (2013.01); B60G 2206/41 (2013.01); B60G 2500/104 (2013.01); B60G 2600/21 (2013.01); B60G 2800/162 (2013.01); F16F 2222/12 (2013.01); F16F 2224/02 (2013.01); F16F 2228/066 (2013.01); F16F 2230/36 (2013.01); F16F 2230/42 (2013.01); F16F 2232/08 (2013.01); F16F 2234/02 (2013.01)] 6 Claims
OG exemplary drawing
 
1. A cylinder apparatus comprising:
a first cylinder sealingly containing hydraulic fluid therein;
a first piston slidably fitted in the first cylinder and defining an inside of this first cylinder into a rod-side chamber and a bottom-side chamber;
an oil passage provided at the first piston and configured to establish communication between the rod-side chamber and the bottom-side chamber;
a disk valve configured to suppress a movement of the hydraulic fluid flowing in the oil passage to generate a damping force;
a piston rod coupled with the first piston;
a closing member provided on one end side of the first cylinder and configured to close the first cylinder with the piston rod inserted therethrough; and
a stopper mechanism configured to operate when the piston rod extends and moves toward an end portion inside the first cylinder,
wherein the stopper mechanism includes:
a second cylinder provided movably relative to the piston rod, the second cylinder including a bottom portion on the one end side of the first cylinder and a cylinder portion extending from the bottom portion toward the other end side of the first cylinder, at least a portion of an outer periphery of the second cylinder being configured to be slidably moved relative to the first cylinder; and
a second piston provided so as to be able to move along with a movement of the piston rod to be fitted to the second cylinder,
wherein a spring member is provided between the second cylinder and the closing member,
wherein a first communication passage is provided at the second cylinder, the first communication passage being configured to establish communication between an inside of the second cylinder and a chamber on the closing member side, the first communication passage being provided at the bottom portion, and
wherein a passage area variable mechanism is provided in the first communication passage, the passage area variable mechanism being configured to reduce a passage area of the first communication passage during an extension stroke of the piston rod and increase the passage area of the first communication passage during a compression stroke of the piston rod.