摘要 |
A mining machine including a cutting drum, a plurality of bits mounted on the cutting drum, a base, and a boom extending between the base and the cutting drum for mounting the drum on the base. The mining machine further includes a primary cutting drum turning mechanism attached to the boom and in driving connection with the cutting drum for causing cutting movement of the cutting drum at a cutting drum cutting speed, and a secondary cutting drum turning mechanism attached to the boom and in driving connection with the cutting drum for causing turning movement of the cutting drum at a speed much less than the cutting drum cutting speed. |