Cycloidal drill bit

Abstract

Sonic energy in a cycloidal or quadrature wave action pattern is generated in a drill stem by means of a sonic oscillator employing an eccentrically weighted rotor. The sonic energy is transmitted down the drill stem to the drill bit to cause precession of the bit around the bottom of the drill bore in a cycloidal fashion. This causes highly effective cutting action of both the bottom and the immediately adjacent side walls of the bottom portion of the bore by virtue of the cycloidal precessing action. In one embodiment of the invention, the drill stem is attached directly to the drill bit such that a nutating type action occurs. In other embodiment of the invention, the drill stem is coupled to the drill bit through an appropriate bearing, which may be a sleeve bearing or a roller bearing, which permits separate rotation of the bit on the drill stem in an orbiting cycloidal fashion.

Dependencies are inferred from the claim text.