| 摘要 |
<p>PURPOSE:To avoid accumulation of positioning errors by setting a positioning original point at a place near a designated point on an object to be processed. CONSTITUTION:The feeding characteristics are set at 1mum/pulse and also at the front of a prescribed positioning point X, and at the same time a new positioning original point OR is set at a position with a distance MO from the home position HP. Then a precision scale 5 with a pulse signal output is set so as to start its operation just at the point OR. Then a feed stage 1 is shifted from the position HP to pass through the point OR. The scale 5 starts to deliver pulse signals as soon as the stage 1 passes through the point OR. The output characteristics of the scale 5 are also set at one pulse/mum. Hereafter other positioning points X1, X2- are decided based on the pulse signal output of the scale 5 with the point OR set as the start point and with control of the shift of the stage 5 while confirming the position of the point OR each time.</p> |
