In one aspect of the invention a rotary drag bit has a bit body intermediate a shank and a working surface. The working surface has a plurality of blades converging at a center of the working surface and diverging towards a gauge of the working surface. At least one blade has a cutting element with a...http://www.google.es/patents/US8122980?utm_source=gb-gplus-sharePatente US8122980 - Rotary drag bit with pointed cutting elements
