| 摘要 |
PURPOSE:To obtain the title detector having a small dimensional size and high resolving power, by providing the second single magnetic track having a total area continuously recorded thereon other than the first magnetic track wherein a magnetic pole of the min. magnetic recording unit is constituted of a continuous recording part of a required length and a non-magnetizing part. CONSTITUTION:A magnetic drum 5 is divided into five magnetic tracks M, M0-M3 and magnetic poles of a magnetic recording unit of an NS pitch lambdaare continuously recorded on the entire periphery of the magnetic track M while 2, 4, 8 and 8 magnetic poles of a magnetic recording unit lambda of a pitch are respectively recorded on the magnetic tracks M0-M3 and magnetic recording parts of 2lambda, 4lambda, 8lambda, 8lambda and blank parts not magnetically recorded are alternately arranged. When the drum 5 rotates, a magnetic sensor 4 applies digital processing to the electric signals obtained from magnetic resistor elements R01-R31, R02-R32 detecting the magnetic signals of the magnetic tracks M0-M3 to obtain absolute outputs. Sine wave or almost sine wave like outputs are obtained by the magnetic resistor elements R1-R4 detecting the magnetic signal of the magnetic track M and, when the outputs of both of them are combined, a position can be detected with high resolving power. |
