摘要 |
In a U-cup based seal of a rod, the basic body of the U-cup 3 is recessed relative to a square cross-sectional shape in the region of a radially inner outer edge 18 on the low pressure side in order to obtain a space 17 between the U-cup 3 and the opening, i.e. the passage opening 16 of a sealing gap 15, leading into a rectangular groove 4 guiding the U-cup 3. This space 17 remains at least partially also upon pressurization such that the U-cup 3 complete remains in the groove 4 upon pressurization and is not extruded into the sealing gap 15. This considerably reduces wear of the U-cup 3. An inner surface 24 of the U-cup shows liquid dragging bore reliefs formed as recesses 25 in the inner surface 24 of the U-cup 3 for transferring hydraulic liquid, disposed on a surface of the translatory movable machine part 1, from a low-pressure side N of the U-cup to a high-pressure side H of the U-cup 3 upon translatory movement of the movable machine part 1. The recesses 25 each extend in an axial direction from the low pressure side N of the U-cup towards the inner sealing lip 7 and each recess is radially confined by side walls 26 which converge in the direction of the inner sealing lip such as to form an imaginary intersection located beyond the inner sealing lip 7 on the high-pressure side of the U-cup 3. |