| 摘要 |
A puncher comprising two drills held on chucks attached on shafts combined with gears provided in two front seats and a rear seat able to be changed in their position so as to change the distance between the two drills, the front seats and the rear seat being connected with a main seat which is possible to be moved up and down by means of a vertical threaded rod and a support rod so as to lower down the two drills to punch holes in one of many distances adjustable in papers placed on a bottom base and pinched immovable in a pincher on the base.
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