Patent ID: 11858090
Assignee: DISCO CORPORATION
Field: Machine tools (Mechanical engineering)
Classification: CPC B | IPC B

Claim 9:
10. A grinding apparatus comprising:
a cassette rest base for placing thereon a cassette for housing a workpiece unit that includes a workpiece and a tape affixed to a surface of the workpiece;
a chuck table for holding the workpiece unit thereon;
a delivery mechanism for delivering the workpiece unit between the cassette and the chuck table;
a first measuring unit for measuring a value of a thickness of the workpiece unit held by the delivery mechanism or a value to be used to calculate the value of the thickness of the workpiece unit held by the delivery mechanism;
a second measuring unit for measuring a value of the thickness of the workpiece unit held on the chuck table or a value to be used to calculate the value of the thickness of the workpiece unit held on the chuck table;
a grinding unit for grinding the workpiece unit held on the chuck table; and
a control unit for controlling the chuck table, the delivery mechanism, the first measuring unit, and the grinding unit,
wherein the control unit includes a deciding section for deciding whether the workpiece unit is a target to be ground or not depending on the value of the thickness of the workpiece unit that is obtained from a result of the measurement performed by the first measuring unit on the workpiece unit after the workpiece unit has been delivered from the cassette and before the workpiece unit is delivered to the chuck table,
wherein the deciding section decides whether the second measuring unit is operating normally or not by comparing the value of the thickness of the workpiece unit that is obtained from a result of the measurement performed by the second measuring unit and the value of the thickness of the workpiece unit that is obtained from the result of the measurement performed by the first measuring unit with each other.