| 摘要 |
PURPOSE:To prevent the excessive grinding of abrasive grains on a polishing surface by providing a contact display unit which is operated by the signal from the contact detecting unit being attached on a polishing surface restoring device, so that the abutting end of a fitting member can be positioned in such a state as it is properly brought into contact with the polishing surface of an endless sanding belt. CONSTITUTION:In the condition that an endless sanding belt 13 is running, a handle is turned to press the abutting edge 31 of a grinding board 30 on the polishing surface of the belt 13. In this case, the contacting edge 55 of a contact detecting unit 40 is also brought into contact with the polishing surface, and as the belt 13 runs, a detector rod 53 vibrates. This vibration is detected by a vibration sensor 54, and the positioning display is shown on a contact display unit 56. And at this point of time the turning operation of the handle is set at the center. Thus, the abutting edge 31 is properly brought into contact with the polishing surface, thereby the abrasive grains on the belt 13 are ground by the grinding material layer thereof as much as a proper quantity, and an optimum restoring treatment can be carried out. |
