Patent ID: 7306047

Claim:
A drilling machine comprising: a frame having one end; a motor fixed within the frame and having an output shaft extending toward the one end of the frame; a rotation shaft extending toward the one end of the frame and having an axis, the rotation shaft being coupled to the output shaft of the motor so as to rotate therewith, the rotation shaft including a slidable section disposed over an end portion of the rotation shaft which is configured so as to be slidable with respect to the rotation shaft and so as to prevent rotation of the slidable section with respect to the rotation shaft, the slidable section having one end provided with a drill bit attachment section and another end serving as an impact-receiving section; a piston extending in parallel with an axial direction of the axis of the rotation shaft, and slidable in a reciprocatory manner in the axial direction to impact the another end of the slidable section; a piston drive unit reciprocally driving the piston with a compressed fluid; and a compressed fluid supplying unit disposed within the frame for supplying the compressed fluid to the piston drive unit.