Patent ID: 8235147

Claim:
An apparatus for forming a borehole in an earthen formation, comprising: a drill bit having a distal cutting end and a proximal end configured for coupling; a side cutting apparatus comprising; a first end configured for coupling to the drill bit and a second end configured for coupling to a drill stern; a first cam structure having at least one groove formed therein, the at least one groove being laterally radially offset relative to the first cam structure; at least one cutting element having a base portion disposed at least partially within the at least one groove and a cutting portion depending from the base portion and radially extending from the first cam structure; a second cam structure positioned adjacent the first cam structure for retaining the at least one cutting element within the at least one groove; a sleeve rotatably coupled to one of the first cam structure and the second cam structure and fixedly coupled to the other of the first cam structure and the second cam structure; and an outer sleeve positioned over at least one of the first cam structure and the second cam structure and having at least one aperture formed in a side wall thereof, the cutting portion of the cutting element extending through the aperture at least when in the second extended position; whereby rotation of the drilling stem in a first direction causes the at least one cutting element to be in a first retracted position relative to the sleeve and rotation of the drilling stem in a second direction causes the first cam structure to rotate relative to the second cam structure to thereby force the at least one cutting element to move along the at least one groove to a second extended position.