HYDRAULIC DAMPER WITH SUB CYLINDER

PROBLEM TO BE SOLVED: To prevent the occurrence of an unexpected damping force caused by a narrow oil passage when a main cylinder and a sub cylinder are provided in a rear cushion 25 and communicated with each other by the oil passage. SOLUTION: A main cylinder 63 and a sub cylinder 40 are provided in a damper 50 of the rear cushion 25, and connected to each other at an upper part 38. The main cylinder 63 is not coaxial with the sub cylinder 40, and an oil passage 72 is formed on the inner side of the upper part 38. The diameter R1 of the main cylinder 63 and the diameter R2 of the oil passage 72 are substantially equal to each other to prevent occurrence of the damping force in the oil passage 72. A bulkhead 73 is provided on the inner side of the upper part 38 between the oil passage 72 and the sub cylinder 40, and a throttling passage 74 is formed therein. A gas chamber 76 is formed in the sub cylinder 40, and working fluid is made to flow in the oil passage 72 and the sub cylinder 40 via an elastic membrane 75. COPYRIGHT: (C)2004,JPO&NCIPI