摘要 |
The element (26) has external housing comprising inner gear teeth that co-operate with outer gear teeth (28, 29) of a spring-loaded section (27). The element is clamped in a housing part and cooperatively equipped with the external housing. Membrane valves are provided in the housing part, and the outer gear teeth include a thread angle such that resistance against a screw of the housing parts is larger than a fixed screw. |