PURPOSE: To operate a release plunger with small force by connecting a tranmission means which has a designated transmission ratio and is useful for operating the release plunger to a piston rod in the frictional connecting state and in the shape connecting state. CONSTITUTION: A male screw 13 formed on a piston rod 11 of a gas spring is fitted to a female screw 13a of an adapter casing 12 of a hydraulic operated release device 10, and a release plunger 14 for releasing a lock device is extended in the longitudinal direction of a piston rod 11. An oil pressure chamber 15 filled with hydraulic oil 16 is formed in the adapter casing 12. A first piston 17 has a diameter larger than that of a second piston 18, so that when the first piston 17 is pushed into the hydraulic chamber 15, the second piston 18 is pushed out of the hydraulic chamber 15 to be put in the operational connecting state with the release plunger 14. A seat part support receiving part 22 has a screw thread 25, and is connected to a seat support of a height adjustable furniture by the screw thread 25.
展开▼
