摘要 |
A vacuum operated lifting apparatus includes a piston having a pressure side and a suction side, respectively, and being movably received in a cylinder, wherein a piston shaft projects through a bottom of the cylinder from the pressure side of the piston and having a through passage for connecting the piston pressure side with the atmosphere. An axially compressible space is connected to a vacuum source for evacuation of the chamber and sealed in air-tight attachment to the piston suction side, the space being confined within the wall of a flexible bellows. |