Drag bit excavation

Abstract

Abstract In a drag bit excavating device having a plurality of cutting elements, each element comprising a core extending along an axis; a bit carrier supported on the core; cutter bits supported by the carrier along a three dimensional spiral having constant pitch and increasing radius along at least a portion of the axis, the carrier being relieved to provide radially extending spaces between the turns of the spiral; a frame supporting the core, carrier, and bits for rotation about and advance along the axis; and a drive to provide rotation, whereby bits slot the material to be excavated while the material between portions of the resulting slot extends into the spaces to be subsequently broken away; support means for supporting the elements in an array sloping along a plane with their respective axes parallel to each other, the plane sloping in a direction transverse to the axes, the axes being spaced along the plane in the direction of slope, the elements having their drives arranged so that each core, carrier, and bit assembly rotates clockwise when viewed along its axis with the plane sloping upwardly to the right.

Inventors

• 👤 Carl R. Peterson

Bibliographic Details