| 摘要 |
<p>DRIVER FOR HELICAL THREAD INSERTS The present invention is directed to an improved driving mandrel for insertion of spiral thread inserts into complementally tapped bores. The mandrel comprises a generally cylindrical structure having a drive tooth at one end for engagement with the tang of an insert, the device being characterized by its being formed of a resilient polymeric material having rigidifying means located at a zone adjacent the drive end, whereby the body portion of the mandrel beyond the zone is subject to limited deflection under torsional and lateral displacing forces. In accordance with a preferred embodiment, the mandrel includes a readily compressible zone in registry with the trailing end of the insert, whereby the insert may be supported against elongation and yet be free to contract as it is driven into the bore, greatly reducing the possibility of cross threading.</p> |
