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An Arrangement in connection with Drilling and Boring Machines for Mining, Quarrying and like Operations, of a Nut, Crossbar or Clamp on the Feed or Driving Screw, to Effect with Withdrawal of the Drill from a Hole.
An Arrangement in connection with Drilling and Boring Machines for Mining, Quarrying and like Operations, of a Nut, Crossbar or Clamp on the Feed or Driving Screw, to Effect with Withdrawal of the Drill from a Hole.
17,662. Teakel, G. W. Feb. 1, 1912. Drilling.-In a portable drilling-machine, a back nut 6 is provided on the feed-screw to engage between the frames 7 on reversal and allow the drill to be withdrawn. The drill is positively secured to the feed-screw.
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