Earth drilling machine

Claim 1

In a drilling mechanism comprising a rigid lower frame, upstanding column means rigidly connected to said lower frame, rigid cross frame means mounted for up and down travel along said column means, and drilling equipment carried by said cross frame means comprising a rotary drill head connectible to drill pipe, motor means and transmission means drivingly connecting said motor means to said drill head, the improvement of: said column means comprising a single pair of spaced apart, parallel, guide columns; said cross frame means including guide means engaging the two guide columns and guiding said cross frame means for precision movement along said guide columns; said cross frame means extending laterally from the general plane of said guide columns and overhanging said lower frame; said motor means comprising a pair of drill motors located above the overhanging portion of said lower frame; said transmission means comprising collector gearing means carried by the overhanging portion of said cross frame and comprising an output portion connected to the drill heat and two input portions, and gearing means drivingly connecting the drill motors to the input portions of said collector gearing means; at least one thrust ram comprising an upwardly directed, downwardly opening, hollow piston chamber having a normally closed upper end, a lower end mounting portion, and a downwardly directed piston slidably receivable in said chamber, said piston having a lower end mounting portion and an upper head portion, means rigidly affixing the lower end mounting portion of said chamber to said traveling cross frame means, with the remainder of said chamber extending upwardly above said traveling frame means, means affixing the lower end of the piston to said lower frame means; selectively usable means for simultaneously delivering a motive fluid between the closed upper end of the chamber and the head portion of the piston and venting the zone below the piston head; to move the traveling cross frame means and the rotary drilling equipment and chamber mounted thereon upwardly as an assembly; selectively usable means for simultaneously delivering motive fluid to the zone below the piston and venting the space above the piston head, so as to cause a downward movement of such assembly comprising the traveling cross frame means and the piston chamber and drilling equipment carried thereby; said rotary drill head including a tool joint component mounted for limited axial movement; a linear fluid motor supported above said drill head tool joint component, said motor including a piston and a fluid chamber below said piston, a connector rod interconnected between said piston and said drill head tool joint component; and means for delivering a fluid into said fluid chamber for exerting a lifting force on said piston for counterbalancing the weight of the drill head Tool joint and any drill pipe members attached thereto.