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