| 摘要 |
<p>The case has a clamping unit e.g. locking collar (11), for axially holding external parts (10) and internal parts (2) of a control crown (C) in an angular position determined with respect to a longitudinal axis of a tube (3). The internal parts have first angular indexing grooves (2a), and the external parts have second angular indexing grooves (10a). The indexing grooves are shaped so as to engage axially with one another by relative axial movement between the internal parts and the external parts. The indexing grooves are maintained by the clamping unit.</p> |
