Grinding apparatus and grinding method

Abstract

A grinding apparatus grinds a workpiece by rotating the workpiece held by main spindles and a grinding wheel held by a wheel spindle, and by relatively moving the grinding wheel toward and away from the workpiece. The grinding apparatus includes a first detection unit that detects a rotational phase of the workpiece; a second detection unit that detects a grinding resistance moment at a grinding point between the grinding wheel and the workpiece, or detects a drive current of a rotary drive unit of the workpiece or a rotary drive unit of the grinding wheel; a storage unit that stores the grinding resistance moment or the drive current in a manner associated with the rotational phase; and a determination unit that determines a slip between the workpiece and the main spindles based on the grinding resistance moment or the drive current at a current rotational phase, and on the grinding resistance moment or the drive current at the same phase as the current rotational phase of a previous time.

Dependencies are inferred from the claim text.