PIPELINE UNDERMINING MACHINE AND CATERPILLAR-TRACKED UNDERCARRIAGE Russian patent published in 1998 - IPC

FIELD: mechanical engineering. SUBSTANCE: undermining machine has frame, drive undercarriage mounted on frame, identical left-hand and right-hand working tools. Working tool has tine mounted on frame for forced rotation about vertical shaft, cylindrical drive auger-type cutter, cylindrical blade disposed behind cutter in axial alignment with it and annular cutter positioned in front of blade. Auger-type cutter is mounted on lower end of tine laterally of it and auger-type cutter axis of rotation is in horizontal position. Tine vertical shaft is offset relative to axis of rotation of auger-type cutter and disposed opposite to blade. Annular cutter and blade are fixed on tine. Undercarriage has frame and caterpillar track including plated chains mounted on frame by means of tensioner and drive sprockets, rigid cross-pieces disposed in planes perpendicular to longitudinal axis of undercarriage, brackets rigidly connected with cross-pieces ends and flexible supporting members. Cross-pieces are secured on inner and outer plates of pulling chains. Brackets project outside outer surface of mid portion of caterpillar track. Flexible supporting members are connected with brackets so as to prevent these members from linear movement, and their length is sufficient for stretching about outer contour of pipeline section. EFFECT: increased efficiency, simplified construction and enhanced reliability in operation. 5 cl, 14 dwg