| 摘要 |
<p>This disclosure relates to a hole cutter comprising a spindle (10) having a rearward end (12) shaped to be engaged and rotated by a drive machine, the spindle further having a front end and an axial center bore (14). A cylindrical blade (44) is attached to the front end of the spindle. A centering pin (20) is supported in telescopic relation within the center bore (14) of the spindle, the pin engaging with the spindle to limit the forward movement of the pin relative to the spindle. A spring (28) is supported in the center bore (14) and urges the pin forwardly relative to the spindle to normally project a portion of the pin forwardly from the spindle and the blade. A center drill (60) is attached to the front end of the spindle and projects forwardly from the blade, the drill having an axial center bore (64) which receives the projected portion of the pin (20). The drill further has a bit (62) attached to its front end. <IMAGE></p> |
