Method for reproducing a reference position

摘要

In this method, a reference position can be reproduced at any time independently of the instantaneous position of the objects (A and B) movable relative to one another. After decoupling of the objects (A or B) to be measured, either the scanning plate (8) or the measuring graduation (4) of a measuring device is pivoted until a reference mark (Ri) is overrun. The scanning of the overrun reference mark (Ri) generates in the counter (Z) a signal with which the counter (Z) is set to the value "zero" or to another prescribed value. Starting from there until the return to the instantaneous starting position, the grating lines of the graduation (4) are counted, so that subsequently the difference is known with respect to the reference mark (Ri) which represents the reference position. The measurement position is reproduced by return to the instantaneous starting position, and the operations can be continued. <IMAGE>