Fundamentals of a new absolute magnetic scale using nonrepeated codes

AbstractFor the linear displacement measurement in industrial machines, a linear scale using a magnetic phenomenon is superior to environment‐resistance. An absolute‐type magnetic scale has the feature of providing safety of a position information with high reliability. Until now, an absolute‐type magnetic scale writes a position information at plural parallel tracks. The scale becomes large‐sized for a long measuring length. Furthermore, a fine magnetic pattern of the scale is needed for a high resolution. From the practical viewpoint, however, the fine pattern makes the clearance of detecting head and scale small. For the solution of these problems, a new magnetic scale is proposed where an absolute position information is written at series on one track accompanying a parallel incremental track. The scale is expected to be small‐sized and to show a high efficiency having a long measurement range without decreasing accuracy and resolution. from the above, the new absolute‐type magnetic scale with absolute track is made where the position‐information is written in at series by using nonrepeated codes and with a parallel incremental track.Furthermore, the operation and structure, pe