| 摘要 |
PURPOSE:To prevent the generation of residual cutting even if a cutting point is placed in the rotary center part of a work, by rotating a tool around the axial line at an angle with the axial line of the rotated work and controlling to relatively move the tool and the work in the both axial directions while generating an ellipsoid. CONSTITUTION:A work 20 is protrusively provided eccentrically to one end of a rotary main spindle 22 having a rotary axial line U tilted with respect to a rotary axial line T of a work W, and the work W and the tool 20 are relatively moved respectively in the direction (B-axis) of said line T and the direction (A-axis) of said line U while a rotary oval surface is cut and formed to the work W. Said relative movement is controlled by a numerical control (NC) device in accordance with the following formula. Assuming an angle theta formed by the line U of the spindle 22 and the line T of the work W for sintheta=ad/2b<2> (a: long diameter, b: short diameter, d: rotary diameter of tool) and X, Z for respectively a moving distance in the direction of each axial line, the relation is Z= b<2> 1-(a-X)<2>/(a<2>-b<2>) -d<2>/4 <1/2>. |
