| 摘要 |
PURPOSE:To decrease the effect to a machined diameter, by providing a step difference in a mounting surface of a headstock to a bed in a horizontal bed lathe, equalizing minimum distances, from the center of a spindle to each mounting surface tightening position, and arranging a direction of the thermal displacement of the spindle to a direction at a right angle with the cutting direction of a tool. CONSTITUTION:A tool 7 in a horizontal bed lathe is sloped to a same direction for a horizontal level. A mounting surface of a headstock 5 to a bed 1 is formed by the first and second mounting surfaces 1a, 1b having a step difference, and the first lower mounting surface 1a is arranged below a spindle 2, while the second mounting surface 1b higher than the former is successively arranged to a cutting line direction of a tool 6. Minimum distance from the center of the spindle 2 to tightening points A, B of bolts 8a, 8b for these mounting surface 1a, 1b are equalized, further bolts 8c, for providing tightening strength, are arranged in positions on the mounting surfaces 1a, 1b farther from the center O than for the tightening points A, B, then the thermal displacement to a direction Y-Y is generated to the direction at a right angle with the cutting direction of the tool 6. |
