| 摘要 |
<p>The position indicating arrangement for machines, e.g. numerically controlled machines, showing the relative positions of two parts moving longitudinally w.r.t. each other can replace the glass rule type with optical sensing and the cam and switch type. An information carrier is fixed on one of the two parts and a corresp. scanner is attached to the other. The scanner detects the difference between two successive regions of a magnetic tape information track both essentially the same distance from the scanner. The regions have different magnetic characteristics, e.g. there are magnetised and unmagnetised regions. The data is read by a Hall Generator magnetic reading head and may be contained on several parallel tracks forming a single tape.</p> |
