| 摘要 |
PURPOSE:To permit a rotary tool to increase its eccentric distance simplifying constitution, by removably mounting the rotary tool to a rotary tool holding shaft through an offset tool having a predetermined eccentric distance. CONSTITUTION:A rotary tool 20 is set to an offset tool 11 in a condition that the tool 20 is eccentrically positioned by the eccentric distance OFT1 from the main spindle center CT1, and the offset tool 11 is mounted to a main spindle 3A. The main spindle 3A, if it is rotated in directions E, F, rotates the rotary tool 20 through a connecting shaft 11b and gears 11d, 11f, and milling is performed by moving a tool rest 2. While rotating a tool turning shaft 21 by the predetermined amount, a casing 11a of the offset tool 11 is also rotated through a gear 21a and a turning gear 11i, and milling is performed in a prede termined angular position. By this constitution, a machine tool, eliminating the necessity for providing a particular eccentric device in a side of the main spindle 3A and for forming a spindle head part in a large size, enables machin ing to be performed in a condition that the rotary tool increases its eccentric distance. |
