Pneumatic spring for a height-adjustable microscope slide column comprises a spring unit arranged in a pressure cylinder, and a working piston loaded by the spring unit in the extension direction of a piston rod

摘要

Pneumatic spring comprises a pressure cylinder (1) divided into a first (5) and a second working chamber (6) by a working piston (4) and filled with a pressurized medium, a bypass line connecting the first working chamber to the second working chamber, a shut-off valve (40) blocking the connection between the first and the second working chamber, and a spring unit connected in series to the pneumatic spring and loading the pneumatic spring in the extension direction of the piston rod (35). The spring unit is arranged in the pressure cylinder and the working piston is loaded by the spring unit in the extension direction of the piston rod. The first working chamber is divided by a step piston (7) displaced in the pressure cylinder into a first pressure chamber (8) facing away from the working piston and a second pressure chamber (9) facing the working piston. The first and second pressure chambers are interconnected. The large step (17) of the step piston faces the seco nd pressure chamber and the small step (14) faces the first pressure chamber. The step piston is displaced against a spring force in the direction of the first pressure chamber. A guide piston (11) fixed in the first working chamber has a guide bore (13) through which the small step of the step piston is displaced in a tightly sealed manner.