| 摘要 |
<p>A bit for drilling a hole. The bit includes a support member, the support member having a passageway extending substantially longitudinally therethrough; a substantially annular crown defining a crown distal end and a crown proximal end, a radially inwardly located crown inner surface and a radially outwardly located crown outer surface, the crown extending from the support member; a slot extending between the crown inner and outer surfaces from the crown distal end substantially longitudinally towards the crown proximal end, the slot defining a slot first side wall, a substantially circumferentially opposed slot second side wall and a slot proximal wall extending therebetween substantially opposed the crown distal end; and a reinforcing member extending substantially circumferentially across the slot between the slot first and second walls; wherein the slot includes a slot proximal segment extending between the reinforcing member and the slot proximal wall and a slot distal segment extending between the reinforcing member and the crown distal end.</p> |
