Rotating post activator for swinging vehicle door

In a device for activating a rotating post for moving a swinging-door panel, the post comprising a hollow cylinder rotatably mounted in mounts at both ends and accommodating a worm gear driven by bi-directional pneumatic piston-and-cylinder drive means including a piston rod attached to the worm gear and positioned with a guide rigidly fastened to one of the mounts to permit only longitudinal movement of the piston rod relative to the guide, the improvement wherein the piston-and-cylinder drive means is completely accommodated inside the hollow cylindrical post and comprises a sleeve rigidly fastened to and coaxial with one of the mounts, at least two piston-and-cylinder units aligned in the sleeve and pneumatically connected in parallel with each unit having a piston and cylinder and wherein the piston rod connects the pistons, means rigidly fastening the guide to an end of the sleeve facing the worm gear, first means receptive of a pressure medium to effect movement of the panel in one direction comprising an axial bore supplying pressure medium to one cylinder and an axial bore in the piston rod communicating with the insides of the cylinders in the vicinity of each piston face that faces the same direction, and second means receptive of a pressure medium to effect movement of the panel in the other direction comprising a supply channel with an essentially annular cross-section positioned between an outside surface of the cylinders and an inside surface of the sleeve and that communicates with the insides of the cylinders in the vicinity of each piston face opposite the piston faces of the first means.