Patent ID: 9604342
Date: 2017-03-28
CPC Classifications: B24B

Claim:
1. An eyeglass lens processing apparatus for processing a periphery of an eyeglass lens, the eyeglass lens processing apparatus comprising: a lens rotating unit configured to rotate a lens chuck shaft for holding the eyeglass lens; a tool rotating unit configured to rotate a tool spindle to which a roughing tool for roughing the periphery of the eyeglass lens is attached; a moving unit configured to move the lens chuck shaft relative to the tool spindle; a controller configured to control the lens rotating unit and the moving unit based on a roughing path, which includes a finishing margin relative to a target lens shape, for roughing the periphery of the eyeglass lens by the roughing tool, such that the roughing tool cuts the periphery of the eyeglass lens up to the roughing path without rotating the eyeglass lens in a first stage and the roughing tool moves along the roughing path while rotating the eyeglass lens in a second stage; and a calculating unit configured to calculate control data of the lens rotating unit at the second stage, wherein the calculating unit is configured to determine a first load torque to be applied to the lens chuck shaft at every rotation angle of the lens based on condition data including the roughing path, thickness at a radial position of the lens around a chuck center of the lens chuck shaft and a diameter of the roughing tool, and obtains a rotation speed of the lens at which the first load torque per unit time becomes equal to or lower than a reference value, and wherein after the roughing tool cuts the periphery of the eyeglass lens up to the roughing path in the first stage, the processing controller is configured to change from the first stage to the second stage and the roughing tool starts roughing the periphery of the eyeglass lens from a position where the roughing tool has cut the periphery of the eyeglass lens up to the roughing path in the first stage.