Abstract

A gas-spring (1) has a hollow piston-rod (2) carrying a piston inside a first diameter cylinder (5). A variable length first annular space (8) is formed along the piston-rod (2) between the piston (3) and a first end cap (6). A second diameter cylinder (9) is arranged concentrically over the first cylinder (5). A first end (9a) is sealed by the first end cap (6) and a second end (9b) sealed by a second end cap (10). The second diameter is larger than the first diameter such that a second annular space (11) is formed along the external periphery of the first cylinder (5). The second cylinder (9) is longer than the first cylinder (5) such that a gap (12) is formed between the first cylinder (5) and the second end cap (10). A cooling fluid connection (13) to the first annular space (8) is provided. The space formed by the second annular space (11), the gap (12) and the second end cap (12), and the hollow piston-rod (2) is arranged to contain pressurised gas.

IPC Classes  ?

• F16F 9/42 - Cooling arrangements
• E02F 9/22 - Hydraulic or pneumatic drives
• F16F 9/02 - Springs, vibration-dampers, shock-absorbers, or similarly-constructed movement-dampers using a fluid or the equivalent as damping medium using gas only