| 摘要 |
PURPOSE:To achieve a precise and stable feeding and positioning free from variations, by providing a shift carriage of a nut holder with a plurality of plate springs at right angles to the axial direction thereof to convert oscillating circular motion of the nut of a motion of displacement vertical and horizontal. CONSTITUTION:A carriage fitting seat 6 is mounted on the undersurface of a shift carriage 2. Plate springs 8 and 8 in which brackets 7 each with an L- shaped cross-section are arranged to be parallel with each other vertically in a square fashion are linked to the fitting seat 6. Moreover, a nut holder 12 for a nut 5 is linked to the brackets 7 through two plate springs 10 and 10 arranged parallel with each other horizontally in a square fashion and four corner bolts 11. With such a machanism, the brackets 7 and the fitting seat 6 can be moved in a parallel manner horizontally being kept facing one another. And the brackets 7 and the holder 12 will be at right angles to the spring 8 in the direction of working a deflection and the swing of the nut 5 makes the holder 12 alone move in a horizontal manner vertically. Thus, the circular motion of the nut 5 due to bending of a feed screw 4 is absorbed by the plate spring 8 and 10 thereby ensuring a precise and stable feeding of the carriage 2 eliminating oscillation thereof. |
