Patent ID: 7677333

Claim:
A drill bit, comprising: a drill bit body; first and second blades formed on said drill bit body; a first cutting element mounted on said first blade, said first cutting element having a first cutting surface geometry corresponding to a first cutting profile; and a second cutting element mounted on said second blade, said second cutting element having a second cutting surface geometry corresponding to a second cutting profile; wherein said first and second cutting elements are positioned on said first and second blades, respectively, so that said first and second cutting profiles partially overlap each other but the first cutting profile does not completely contain the second cutting profile and the second cutting profile does not completely contain the first cutting profile, said overlap creating a high density zone in a middle region provided by both of said first and second cutting profiles and a low density zone in a peripheral region provided on both sides of the middle region solely by said second cutting profile of the second cutting element; and wherein a cutting tip end of said mounted first cutting element is at substantially a same exposure height as a cutting tip end of said mounted second cutting element.