Patent ID: 7849936

Claim:
A directional drilling device for use in drilling boreholes, the device having a singular axis of rotation and being positionable between a drill bit and associated drill collar of a drill string having a longitudinal drilling axis; the device comprising: at least one cutting member movably mounted with respect to a body member, the at least one cutting member being moveable between a first extended position for engagement with the wall of a bore hole and a second position in which it is retracted from engagement with said wall; directional control means for synchronizing the movement of the at least one cutting member between said respective extended and retracted positions in accordance with the rotational position of the body member in the bore hole being drilled to cut a void to create an eccentric channel about the longitudinal drilling axis; and a stabilizing means extending around the body member and having a larger radial diameter than the at least one cutting member when in the second position and operable to contact with the bore hole to steer the drilling device in the direction of the eccentric channel.