CUTTING TOOL OF HIGH RELIABILITY

摘要

PURPOSE:To automatically exchange a tool and enable it to perform cutting in a stable condition, by providing the main tool and the plural spare tools, successively retracting their edge point by a fine distance, to be arranged in the radial direction in the periphery of a disc-shaped tool holding part. CONSTITUTION:A main tool 11 and a plurality of spare tools 12a, 12b, 12c... are arranged in the radial direction on a tool holding member 10 mounted to a main spindle, and the spare tool 12a, so that it may perform cutting action for a work when the main tool 11 is worn or broken due to its cutting, is arranged retracting from the main tool 11 by a fine distance DELTA, hereafter the tool holding member 10, successively retracting the spare tools 12b, 12c,... by a fine distance DELTA by DELTA, arranges the tools as a whole so as to line their edge points on the Archimedes spiral curve. When the main tool 11 is worn or broken, the tool 12a, being placed in the most protruding condition, performs a substantial tool exchange, and the tools 12b, 12c,... successively perform cutting.