| 摘要 |
A sheet metal drill bit for drilling burrless round holes in thin products. The drill bit is formed by a solid drill body having a drill head and a connecting shaft. The drill head has two diagonally opposed outer cutting edges in a front face thereof each defining a flute geometry. A stabilizing central drill bit extends from the front face and beyond the outer cutting edge. The cutting edge has an elevated leading edge portion and a downward sloping trailing portion. A concave well is defined between the outer cutting edge and the central drill bit. The trailing portion tapers to at least the front face from which the central drill bit extends and to an angulated web portion. The concave well retains undrilled product pieces about the central drill bit whereas the web portion permits evacuation of loose drilled material.
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