| 摘要 |
At least three tubes along an axis have a pivot bearing between each two tubes and on which is a protuberance . The pivot bearing consists of an annular sleeve (1) supporting the pin (2) acting as the protuberance. The side of the pin facing the annular sleeve has a thread (3). The sleeve is screwed into the threaded hole in the annular sleeve. The pin fits into a sleeve (4) contained in a hole in the door-leaf which is fixed by at least one screw (6) which goes through a threaded hole (5) in the sleeve, and whose free end fits into a recess, preferably a groove in the pin. |
