| 摘要 |
An air cylinder (100) including a cylinder body (1) of a double cylinder structure, a piston (3) adapted to be moved reciprocally in the cylinder body, and a piston rod (2) connected to the piston. The cylinder body (1) comprises an inner cylinder member (1b) in which the piston (3) and piston rod (2) are slidably held, an outer cylinder member (1a) constituting the double cylinder body with the inner cylinder member, and upper and lower end walls (4, 5) for closing both ends of the inner and outer cylinder members. The piston rod (2) is passed through the upper end wall (4). The inner cylinder member is provided at the top portion thereof with an opening (6), via which the spaces in the inner and outer cylinder members communicate with each other. The lower end wall has a port (10) at which the space in the inner cylinder member is opened to the outside. When the piston rod is pulled up, the compressed air in the inner cylinder member flows into the space in the outer cylinder members, so that the pressure in the cylinder does not increase. |
