Patent ID: 8746370

Claim:
A steerable horizontal drill comprising a back body including an outer case, a connector threaded into the outer case at one end, a back head threaded into the outer case at a second end, the outer case, connector and back head cooperating to define a storage space, the back body further comprises a tube assembly keyed to the connector and held in place by a clamping action of the connector and back head, and a transmitter housing keyed to the tube assembly, an air powered reciprocating hammer, and a drill head including an offset drill face, the drill head moved by the air powered reciprocating hammer to work the ground to thereby form a bore, wherein the connector includes a connector body having a longitudinal axis and a stem having a longitudinal axis, the longitudinal axis of the connector body forms an acute angle with the longitudinal axis of the stem, the outer case has a longitudinal axis, the outer case is removably coupled to the connector body of the connector so that the longitudinal axis of the outer case and the longitudinal axis of the connector body are generally coaxial, the air powered reciprocating hammer has a longitudinal axis, and the air powered reciprocating hammer is removably coupled to the stem such that the longitudinal axis of the air powered reciprocating hammer and the longitudinal axis of the stem are generally coaxial, wherein the steerable horizontal drill further includes a position transmitter keyed to the transmitter housing and wherein the position transmitter, the transmitter housing, and the tube assembly are keyed such that the position transmitter is positionable in only one rotational position relative to the acute angle formed by the longitudinal axis of the connector body and the longitudinal axis of the stem so that a signal of the position transmitter is indicative of the position of the acute angle.