Abstract: A drag bit excavating device 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 the 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.

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

Abstract: A rock boring assembly for producing a straight hole for use in a drill string above a pilot boring bit of predetermined diameter smaller than the desired final hole size. The boring assembly comprises a small conical boring bit and a larger conical boring bit, the conical boring bits mounted on lower and upper ends of an elongated spacer, respectively, and the major effective cutting diameters of each of the conical boring bits being at least 10% greater than the minor effective cutting diameter of the respective bit. The spacer has a cross-section resistant to bending and spaces the conical boring bits apart a distance at least 5 times the major cutting diameter of the small conical boring bit, thereby spacing the pivot points provided by the two conical boring bits to limit bodily angular deflection of the assembly and providing a substantial moment arm to resist lateral forces applied to the assembly by the pilot bit and drill string.

Abstract: A boring apparatus having a working member mounted for rotation on a lubricated bearing about a shaft member, the apparatus being of the type in which substantial radial and axial relative motion between said members occurs in response to radial and axial loading conditions encountered by the working member during operation in an abrasive laden external environment, including an improved seal assembly between the members for sealing the bearing from the environment while accommodating the radial and axial relative motion, the seal assembly comprising a seal carrier mounted in a space between the members, a dynamic seal element supported between the carrier and one of the members to form a dynamic seal therebetween, and a static seal element supported between the carrier and a radially extending surface of the other of the members, the dynamic seal element being axially slidable along the one member to accommodate the axial relative motion, the static seal element being deformable and radially slidable along t

Abstract: Boring apparatus having a plurality of hole-enlarging assemblies comprising shaft-mounted working members. In a convergent arrangement of the axes of the working members the assemblies are completed by insertion of the elongated shafts via a hollow space in the bottom connector, through passages in the frame. The upper ends of the shafts are shown held in holes in the frame, and the exterior upper and lower surfaces of the frame are shown as surfaces of revolution, free of wear points. The passages are shown to form cut-outs in the thread of the connector in the first preferred embodiment. In other embodiments the passages are formed through an extension of the frame preceding the connector, and a two-part connector assembly is provided, the passage entering a hollow space provided by the outer part.

Abstract: A side excavating machine comprising a rotatably driven cylindrical drum adapted to advance generally endwise along a pre-existing working face, but angled so that trailing portions of the drum project beneath the plane of the pre-existing face. The drum has a distribution of rock cutting rollers on its cylindrical surface which are freely rotatable about rolling axes which are fixed in a predetermined relation to the axis of the drum, defining a small forward skew angle. The cylindrical drum is rotatably mounted by bearings on a frame which advances along the working face, with the drum axis lying at a small acute angle to the direction of advance so that trailing portions of the drum excavate rock as the frame advances along the face. The major component of rock-cutting forces thereby applied to the drum is normal to the direction of advance of the frame, and there are means to provide side reaction force to the frame corresponding to this major component of rock-cutting forces.

Abstract: The invention is directed to a method of in situ extraction of a constituent of a rock formation, e.g., copper deposits or particular petroleum deposits as found in oil shale, and to a method of preparing the rock formation for in situ extraction of the rock constituent. Various embodiments of a side excavating machine are also disclosed for preparing the rock for in-situ extraction of a constituent therefrom. The excavating machine breaks the rock in-situ in a manner to form a narrow, horizontal flow-directing chamber in the rock-filled with fluid-permeable broken rock.

Abstract: In boring apparatus of the type having cutters mounted for rotation about respective cutter axes in a frame which is in turn rotatable about a frame axis, each cutter having a body carrying teeth which in operation sweep a surface which is oblique to the axis of advance of the apparatus, that improvement wherein each cutter has selected tooth regions, preferably of alternating high and low tooth densities, spaced along the respective cutter axis, the tooth regions of the cutters are arranged in an ordered cycle progressing along the frame axis, and regions adjacent each other in the cycle are on different cutters and overlap each other along the frame axis.