Patent ID: 7204560

Claim:
A cutting bit comprising: a body having a front surface and a cylindrical side surface portion, the cylindrical side surface portion including a shoulder below the front surface and extending substantially perpendicular to a central axis of the body, at least a portion of the cylindrical side surface portion being disposed above the shoulder; and a ring that is harder than the body attached to the body at a front surface of the shoulder such that the entire said ring is disposed below the front surface of the body, wherein a distance between the front surface and a top of the ring divided by a distance between the front surface and a bottom surface of the body is 0.15 to 0.5., and wherein the body includes a second shoulder below the first shoulder, the body being no larger in diameter above the second shoulder than at the second shoulder, and the cutting bit comprising a second ring attached to the body at a front surface of the second shoulder, wherein a distance between the front surface and a top of the second ring divided by a distance between the front surface and a bottom surface of the body is 0.15 to 0.5.