| 摘要 |
A drill bit comprising: a shaft 103 which has a pyramidal shaped end 105 defining a drill tip with a plurality of edges defining the pyramidal shape; and one or more recesses 107 for directing away debris produced whilst drilling, the or each recess 107 having a first portion 109 extending along the shaft 103 and a second portion 111 which extends along the drill tip, wherein the second portion 111 of the or each recess 107 extends along an edge 113 of the drill tip.
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