Patent ID: 7845435

Claim:
An earth-boring bit comprising: a bit body configured at its upper extent for connection into a drillstring, the bit body having a central axis and a radially outermost gage surface; at least one fixed blade extending downward from the bit body in the axial direction, the at least one fixed blade having a leading edge and a trailing edge; at least one rolling cutter mounted for rotation on the bit body, the at least one rolling cutter having a leading side and a trailing side, and wherein the at least one rolling cutter is next to and leading the at least one fixed blade with respect to a direction of rotation of the bit; at least one nozzle mounted in the bit body proximal the central axis, the at least one nozzle arranged to direct a stream of pressurized drilling fluid between the leading edge of the at least one fixed blade and the trailing side of the at least one rolling cutter; a plurality of rolling-cutter cutting elements arranged on the at least one rolling cutter and radially spaced apart from the central axis of the bit body; a plurality of fixed-blade cutting elements arranged on the leading edge of the at least one fixed blade, at least one of the plurality of fixed-blade cutting elements being located proximal the central axis of the bit body; and a junk slot formed between the trailing side of the at least one rolling cutter, the leading edge of the at least one fixed blade, and a portion of the bit body, the junk slot providing an area for removal of disintegrated formation material, the junk slot being equal to or larger in at least an angular dimension than a space between the leading side of the at least one rolling cutter and a trailing edge of a next leading fixed blade with respect to the direction of rotation of the bit.