| 摘要 |
The device (1) comprises an external casing (11) rotatably coupled to a fastening plate (3) by means of an assembly pivot (5) and provided with a substantially cylindrical cavity having a hemispherical bottom accessible from the outside of said casing (11), a substantially spherical internal casing (21) fastened to an extremity of said arm (2) and housed in said cavity of said external casing (11) and also passed through with clearance (12) by said pivot (5) so as to be inclinable with respect to said external casing (11), and a clamping collar (13) passed through with clearance by said arm (2), said collar being moreover mounted slidably in said cavity of said external casing (11) to act with pressure on said internal casing (21) and to clamp said arm (2) in a desired variable angular position with respect to the central axis of said cavity of said external casing (11). |
