| 摘要 |
PURPOSE:To polish the body to be worked in the specified dimension with good accuracy by descending a rotary jig fitted with the body to be worked with good straightness and providing a non-contact type displacement detector detecting the descent amt. thereof. CONSTITUTION:A displacement computing element 32 detects the distance with the lower face 6a of the rotary jig inside at all times and when the body 34 to be worked is brought into contact with a rotating surface plate 2, a controller 28 stores the value of the value delta0 of the distance of this time. The rotary jig 6 guided by a radial bearing is descending by holding straightness according to the progress of working. Then when the desired working amt. deltaa input by the external part input 26 in advance is achieved, i.e. when delta1=delta0+deltaa is detected by a detector 32, an instruction signal is output from a controller 20 in order to feed a compressed air to the upper side thrust bearing 24 so as to float the rotary jig 6 from the rotating surface plate 2. Consequently, the body 34 to be worked is not processed any more and the body 24 to be worked is subjected to polishing with high accuracy. |
