Patent ID: 7341501
Filing Date: 2008-03-11
Classification: B23F,Y10S

Abstract:
1. A gear grinding machine, comprising: a moving mechanism on which a threaded grinding wheel having a thread spirally formed on an outer peripheral surface thereof is rotatably mounted, the moving mechanism being arranged to move the threaded grinding wheel along an X-direction being a direction in which the threaded grinding wheel moves toward and away from a work grinding position, a Z-direction being a vertical direction, and a Y-direction being a direction perpendicular to the X-direction and the Z-direction, and being also arranged to turn the threaded grinding wheel in a Y-Z plane; an NC device for NC-controlling movement of the moving mechanism in order to control a position of the threaded grinding wheel mounted on the moving mechanism; and a rotary dressing device having a disk-shaped dressing tool, and arranged such that when the dressing tool is set at the work grinding position, the dressing tool contacts flanks of the thread of the threaded grinding wheel, while being rotationally driven, to perform dressing, wherein the NC device exercises control in such a manner as to adjust positions of the threaded grinding wheel in the X-direction, the Y-direction and the Z-direction, and a turning position of the threaded grinding wheel in the Y-Z plane such that the dressing tool contacts the flanks of the thread of the threaded grinding wheel, move the threaded grinding wheel in the Y-direction by a distance corresponding to a lead of the spiral thread during one rotation of the threaded grinding wheel while keeping a state of contact of the dressing tool with the flanks of the thread of the threaded grinding wheel, and progressively change the positions of the threaded grinding wheel in the X-direction and the Z-direction such that a position of contact of the dressing tool with the flanks of the thread of the threaded grinding wheel progressively moves along a circumferential surface of the threaded grinding wheel in accordance with the rotation of the threaded grinding wheel, while keeping the state of contact of the dressing tool with the flanks of the thread of the threaded grinding wheel.