Abstract: A method to correct heat-treatment distortion of plane - generated hourglass worm is proposed, in which the distortion is corrected by producing the "pre - distorted equivalent tooth surface" before the heat treatment. The model of the "pre - distorted equivalent tooth surface" is established. From the actual heat treatment distortion of the worm tooth detected by coordinate measurement, the parameters for machining the "pre-distortion equivalent tooth surface" are obtained. The experiments of the machining and heat-treatment are carried out, and the results show that the method is quite effective in practice.

Key words: Coordinate measurement Correction, Heat-treatment distortion, Plane-generated hourglass worm