| 摘要 |
The invention relates to an operating device for a rotatable closing element of a valve such that, a desired angle of rotation can easily be set and maintained. This is achieved in that two guide grooves (2f), which are incorporated diametrically opposite each other, are bounded on all sides by a piston shank (2b), in that their respective courses are precisely or more or less symmetrical at all points, in that in each instance the courses have, in relation to the axis of the piston (2), a greater pitch angle in a central portion (angle b) than in their two portions on the end side (angle a) (a>b), and in that the stroke of the piston (2) is limited on one side by application of the front-end piston shank (2b) to the cover element (4) and on the other side by application of a piston base (2a) to a stop element (9; 20; 20.1) which is mounted in the housing base (1b) of the housing (1) |
