Patent ID: 7370711

Claim:
A drill bit for drilling through earthen formations and forming a borehole, the bit comprising: a bit body having a bit axis; at least a first and a second cone cutter, each cone cutter being mounted on said bit body and adapted for rotation about a different cone axis, said first cone cutter comprising a backface, a heel surface adjacent to said backface, and at least one circumferential row of intermeshed cutter elements axially spaced apart from said heel surface relative to the cone axis of the first cone cutter; said first cone cutter further comprising an array of N 1 cutter elements mounted in a circumferential band axially disposed between said row of intermeshed cutter elements and said heel surface relative to the cone axis of the first cone cutter; wherein said array of N 1 cutter elements are spaced at non-uniform radial positions relative to said bit axis and include cutting surfaces that when viewed in rotated profile, provide a first composite cutting profile having width W 1 ; and wherein said N 1 cutter elements are disposed in at least P 1 , radial positions, where P 1 is at least five; and wherein at least one of said N 1 cutter elements of said array is mounted at a radial position relative to said bit axis that is different from the radial position of every other cutter element in the array.