Patent ID: 8172644

Claim:
A grinding machine comprising: a first grinding wheel comprises a grinding wheel having a grinding surface formed to be plane; a second grinding wheel comprises a grinding wheel having a plurality of oblique grooves formed on a grinding surface thereof to be inclined relative to a wheel circumferential direction; and a coolant supply device configured to supply coolant to a location at which the first and second grinding wheels grind a workpiece, wherein the plurality of oblique grooves are inclined at a predetermined angle relative to the wheel circumferential direction and are formed at equiangular intervals in such an arrangement that where one side intersection point is defined as an intersection point of each oblique groove and an extension line of one side edge parallel to the wheel circumferential direction of the contact surface and the other side intersection point is defined as an intersection point of each oblique groove and an extension line of the other edge, the other side intersection point of each oblique groove overlaps the one side intersection point of an oblique groove next to each such oblique groove by a predetermined overlap amount in the wheel circumferential direction, and in grinding the workpiece with the second grinding wheel, an infeed amount of the second grinding wheel against the workpiece and at least one of the inclination angle and the intervals of the oblique grooves are set so that the length in the wheel circumferential direction of the contact surface on the grinding surface of the second grinding wheel and the workpiece becomes shorter than the overlap amount.