Abstract: An isolator for a drill assembly that is mountable to a drill is presented. The isolator comprises an elongated outer member with an elongated inner member inserted within the outer member. An elastomer is interposed in the space between said inner member and said outer member. The isolator is connectable to a drill assembly at one end through the outer member and at the other end through the inner member. The isolator is capable of providing sound and vibration isolation when the drill assembly is mounted to a drill.

Abstract: A chuck isolator for the chuck of a drill comprising a base plate mountable to the chuck, a drive plate connectable to a drill bit, and a first elastomeric member interposed between the base plate and the drive plate. The base plate and the drive plate are wider than the drill bit. The chuck isolator is connectable to the chuck of the drill and capable of providing sound and vibration isolation when the chuck isolator is connected to the drill.

Abstract: A rotary drill bit insert that includes an elongate body that is rotatable about a central axis wherein the elongate body has a pair of symmetrical halves symmetrical about the central axis. The elongate body contains a central notch disposed between the symmetric halves of the elongate body. Each symmetrical half includes a leading face and a top surface that has a leading surface and a trailing relief surface wherein the leading surface and the trailing relief surface are contiguous and non-coplanar. Each half also has a leading cutting edge at the intersection of the leading face and the leading surface of the top surface. The leading surface is inclined at a constant angle of inclination in a radial direction with respect to a first radial line projecting from the central axis, and the leading surface being inclined downwardly and rearwardly from the leading cutting edge.

Abstract: A rotary drill bit insert that includes an elongate body that is rotatable about a central axis wherein the elongate body has a pair of symmetrical halves symmetrical about the central axis. The elongate body contains a central notch disposed between the symmetric halves of the elongate body. Each symmetrical half includes a leading face and a top surface that has a leading surface and a trailing relief surface wherein the leading surface and the trailing relief surface are contiguous and non-coplanar. Each half also has a leading cutting edge at the intersection of the leading face and the leading surface of the top surface. The leading surface is inclined at a constant angle of inclination in a radial direction with respect to a first radial line projecting from the central axis, and the leading surface being inclined downwardly and rearwardly from the leading cutting edge.