PURPOSE: To contrive to enhance the surface precision of the work surface of a workpiece by a method wherein a calculating means to calculate the displacement in the direction of a rotating shaft under the rotation of a parting tool on the basis of displacements detected with a first and a second detectors is provided.
CONSTITUTION: A slicing machine 20 produces a wafers from, for example, a silicon ingot SI. A tension disc 42 having a disc-shaped blade 44 is integrally mounted in tandem to the end of a rotatingly-driven main spindle 26. The blade 44 and a shape like a doughnut having an opening at its central part and a cutting edge 46 is formed along the whole periphery of its inner rim so as to constitute a parting tool for slicing. A first and a second displacement gages 54a and 54b, which are arranged respectively opposite to both the sides of the blade 44, consist of magnetic sensors so as to allow to realize the non- contact detection of distance to the corresponding surfaces of the blade 44. Further, the outputs of the displacement gages 54a and 54b, both of which are connected to a subtracter 56, are substracted from each other so as to cancel their variation factors, resulting in disappearing from the detected value.
KAWAGUCHI KEIJI
YAMAZAKI YUKIO
Next Patent: MANUFACTURE OF BOARD FOR INFORMATION RECORDING MEDIUM