| 摘要 |
PROBLEM TO BE SOLVED: To provide a drilling bit wherein a gauge function is added to a cemented carbide tip located on a peripheral side of a head 2 of the bit. SOLUTION: The drilling bit 1 is composed of the head 2 and a body 3, and an end face 2a of the head 2 is provided with a fitting hole 5 wherein the button-shaped cemented carbide tip 4 is implanted. The fitting hole 5 located on a side of an outermost periphery of the end face 2a is formed in such a manner that a peripheral edge of a peripheral part 2b of the head 2 is notched partially. A part of an implanted part 4b is protruded from the peripheral part 2b so that the gauge function for a hole wall during drilling can be added to the tip 4 inside the fitting hole 5.
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