Patent ID: 11858087
Assignee: DISCO CORPORATION
Field: Machine tools (Mechanical engineering)
Classification: CPC B | IPC B

Claim 0:
1. A grinding apparatus comprising:
a chuck table configured to hold a workpiece by a holding surface;
a grinding unit in which a grinding wheel having grinding stones arranged annularly on a lower surface of a base is fitted to a mount coupled to a lower end of a spindle, the grinding unit being configured to grind the workpiece by the grinding stones;
a grinding feed mechanism configured to raise or lower the grinding unit in a direction perpendicular to the holding surface;
a control unit;
a reading unit configured to read a thickness of the base, the thickness being recorded on a recording medium on which at least the thickness of the base of the grinding wheel is recorded;
a base thickness storage unit configured to store the thickness of the base, the thickness being read by the reading unit; and
a detecting unit configured to lower the grinding unit by the grinding feed mechanism, and detect a fitting surface of the mount and a lower surface of the grinding stones of the grinding wheel fitted to the mount;
wherein the control unit is configured to:
store a height of the grinding unit when the grinding unit is lowered by the grinding feed mechanism and the detecting unit detects the fitting surface of the mount,
store a height of the grinding unit when the grinding unit is lowered by the grinding feed mechanism and the detecting unit detects the lower surface of the grinding stones after the grinding wheel is fitted to the mount, and
calculate a remaining amount of the grinding stones by subtracting the thickness of the base, the thickness being stored in the base thickness storage unit, from a difference between the height of the grinding unit when the grinding unit is lowered by the grinding feed mechanism and the detecting unit detects the fitting surface of the mount and the height of the grinding unit when the grinding unit is lowered by the grinding feed mechanism and the detecting unit detects the lower surface of the grinding stones after the grinding wheel is fitted to the mount.