Progressive cutter size and spacing in core bit inner diameter

Abstract

A core drilling bit comprising a tubular body having an inner diameter, an outer diameter, and a leading face spanning from the inner diameter to the outer diameter; and a plurality of cutters mounted in the face; wherein cutters mounted along the inner diameter vary in configuration. For example, the cutters may be progressively larger along the inner diameter. The interior edges of the cutters along the inner diameter may be aligned in a circle with their outer edges being aligned in a spiral. The leading edges of the cutters along the inner diameter may be aligned at a constant depth, a progressively shallower depth, or a progressively deeper depth. The cutters may be spaced progressively wider or narrower along the inner diameter.

Dependencies are inferred from the claim text.