| 摘要 |
<p>An attachment for an automatic lathe ( 10 ) and which is capable of carrying out threading operations without the need for purpose made cams; the attachment having a pair of quills ( 30, 34 ), one ( 30 ) holding a drill bit ( 32 ) and the other ( 34 ) a threading bit ( 36 ), with means such as cams ( 52, 90 ), for interchanging the quills ( 30, 34 ) precisely with respect to a work piece. ( 14 ). The interchange of the quills ( 30, 34 ) and operation of the threading bit ( 36 ) are predetermined</p> |
