| 摘要 |
PROBLEM TO BE SOLVED: To provide a polishing device which permits a workpiece to be polished until a desired thickness is obtained surely, by detecting the change of the relative distance between upper/lower wheels with high accuracy. SOLUTION: The polishing device is provided with a displacement detecting means 17 of a non-contact type which detects a relative displacement between an upper wheel 1 for pressing the workpiece w and lower wheel 2 for supporting the workpiece w. In the displacement detecting means 17, a probe 18 having an exciting coil 23 and a detecting coil 24 is inserted into the shaft center of a hollow hole 2a which is formed in the axial direction of the lower wheel 2, and a differential transformer having a ring shape yoke 19 fixed at a position approximately opposite to each coil 23 and 24 of the probe 18, is provided on the inside surface of the hollow hole 2a; further the top of the probe 18 is connected to the upper wheel 1 to permit vertical motion integrally moving together with the upper wheel. |
