| 摘要 |
A drill bit includes a shank at a first end of the drill bit, a boring head at a second end of the drill bit opposite the first end, and a wrenching section between the shank and the boring head. The wrenching section has a substantially different cross-section than any portion of the shank or the boring head. The wrenching section includes at least one pair of flat surfaces that are parallel to one another. In some embodiments, the wrenching section has a square or hexagonal cross section. A drill motor grips the shank for boring a hole in a workpiece. In some embodiments, the shank is cylindrical or splined, or is configured as an SDS shank, an SDS-plus shank, an SDS-Top shank, an SDS-max shank, or a Morse taper shank. A wrench is applied to the wrenching section to free the drill bit from the workpiece if jammed. |
