Patent ID: 7028790
Filing Date: 2006-04-18
Classification: E01C,E21B,Y10T

Abstract:
1. A drill bit comprising: a body having a distal end with a closed face and a proximal end, the body defining an axis and comprising a first portion adjacent to the proximal end, a second portion adjacent to the distal end, and an intermediate ring wherein a coupling at the proximal end, the coupling adapted for connection with a rotary driver, a depth stop adjustably secured to the first portion by a plurality of adjusting screws wherein the adjusting screws are substantially parallel to the axis, the depth stop being adjustably located between the first portion and the distal end circumferentially around the second portion in a manner to limit penetration of the bit, a plurality of springs located between and biasing the first portion from the depth stop, each spring of the plurality of springs being located circumferentially about one of the plurality of adjusting screws; a primary cutting surface substantially located on the closed face, comprising a plurality of outer diamond cutter segments spaced around a circumference of the closed face and at least one inner diamond cutter segment extending across the closed face, a secondary cutting surface substantially located on the intermediate ring; and a pilot drill extending axially from the distal end of the body wherein the pilot drill is tipped by a cutter tip.