Method of forming tooth grooves

摘要

A cup-shaped grindstone for grinding an end face of an annular portion of a work to form tooth grooves in the end face includes a grinding portion provided around an outer periphery of a disk portion. Abrasive grains of CBN are electrodeposited on each of first, second and third grinding faces of the grinding portion. Cooling-liquid ejecting bores are provided in a lower end of the first grinding face. To form the tooth grooves, the following steps are carried out: a rough-finish processing step cuts the tooth grooves by intermittently feeding the cup-shaped grindstone in a predetermined amount at a time, and a finish processing step of finishing the tooth grooves by retaining the cup-shaped grindstone at a predetermined position after the rough-finish processing step. During both steps, a cooling liquid is supplied from cooling-liquid ejecting bores defined in the first grinding faces of the cup-shaped grindstone.