| 摘要 |
Comprising a hollow rod (1) fitting loosely inside a tube (2) which has a blind end in which is provided a housing (3) of diameter similar to the inner diameter of the hollow rod (1), there being housed inside the tube (2) an elastic element (4) provided with conical ends (5); in such a way that these latter are partially introduced into the inside of the hollow rod (1) and of the housing (3), where they become stuck. In addition, the accessible ends of the hollow rod (1) and of the tube (2) can be fitted with stops. Figs. 1 and 2 . |
