DRILLING MACHINE

PROBLEM TO BE SOLVED: To efficiently construct a desired pipeline by rotatively driving a rotary table by a constant driving force through the use of a water-cooled motor, which does not cause a fluctuation in output, as a driving means for rotatively driving the rotary table. SOLUTION: This drilling machine 1 pushes in a buried pipe 25 while excavating ground, so as to form the pipeline out of the buried pipe 25 in the ground. The drilling machine 1 is equipped with a drilling unit 2 which is provided in the buried pipe 25 and composed of a leading body 3 and a holding body 15, and a propelling device which imparts a propelling force to the drilling unit 2. The leading body 3 comprises: the rotary table 5 which is rotatably provided at a propelling-direction leading end; a driving means 6 for rotatively driving the rotary table 5; and at least one of the drilling bits 10 and 11 which are provided on the rotary table 5 so as to be rotatable integrally with the rotary table 5. The driving means 6 for the rotary table 5 has the water-cooled motor 7 which does not cause the fluctuation of the output. The output of the water-cooled motor 7 is imparted to the rotary table 5, so as to rotatively drive the rotary table 5. COPYRIGHT: (C)2009,JPO&INPIT