| 摘要 |
<p>Coupling device serving as attachment element between the bits and the heads of drills for mining work is constituted by a shaft or cylindrical shank, the base of which is fitted with oblique driving tenons operating in conjunction with the head of the drill, and a case following the part with tenons. The case incorporates means allowing the utilisation of a tightening tool, comprising a body having a section fitting the tool and/or a thread or a drilling having a section fitting the tool and/or a thread or a combination of the two. The invention resolves the problem of providing a tightened mounting between the head of the drill, the coupling device and the bit, which it is not possible to realise in existing devices, in which the bit is screwed into the case or welded.</p> |
