| 摘要 |
<p>A small size high precision position detector for automatically detecting a hand position which is necessary for adding a function such as automatic time setting of a timer. An identification pattern (20) where identification marks are provided discretely is made of a hard magnetic thin film. The surface of the center wheel (17) moved interlockingly with the minute hand (12) serves as an encoder face. The existence of the identification marks are sampled by a magnetic sensor (21b) at a plurality of sampling points. The detection signals of the magnetic sensor at the respective sampling points are sorted into three types of data, '1' meaning that the identification mark exists, '0' meaning that the identification mark does not exist and '*' meaning that the identification mark is indefinite. The sampling codes which are obtained by the data of a plurality of the sampling points are compared with a reference identification code to determine the position. Further, by arranging the identification patterns regularly in relation to the sampling points, the errors of the indefinite data can be corrected.</p> |
