| 摘要 |
1. A thrust piston device having a membrane seal (6; 84) which bridges across the gap between the piston (2; 92) and the surrounding housing (4; 70), where the piston and the housing form for the membrane (6; 84) bearing surfaces (10, 12; 98, 78) which are inclined in opposite senses and on and off which the membrane rolls during the motion of the piston relative to the housing, and these bearing surfaces run inclined with respect to the direction of motion of the piston so that through the motion of the piston the membrane gets inverted from the shape of the bearing surface (12; 78) on the housing into the shape of the bearing surface (10; 98) on the piston, characterized in that the housing (4; 70) is provided with a bearing surface (12; 78) curved to the shape of a hollow sphere and the piston (2; 92) is provided with a bearing surface (10; 98) curved to the shape of a sphere of approximately the same radius and that the membrane (6; 84) at least in the region of its rolling contact with the bearing surface (12, 10; 78, 98) exhibits in the undeformed state a curvature to the shape of a sphere of approximately the radius of the bearing surfaces. |
