| 摘要 |
PURPOSE:To detect an absolute position without mechanically returning to an original point by a simple constitution, by outputting an absolute code before the rotation of a rotary encoder, and outputting a code having many slits after the rotation as two-phase pulses. CONSTITUTION:An FF6 is not set until the coincidence of an absolute position code through light receiving elements 3a, 3b... of an absolute type disk 2 before rotation and a counted clock value from a counter 5 is detected by a comparator 4. In correspondence with the output of the lower 2 bits from the counter 5, two phase pulses based on the absolute code are outputted from a two phase pulse converter 8 comprising an exclusive OR gate 81 through AND gates 73 and 74, OR gates 75 and 76, and the like in a data selecting part 7. When the disk 2 is rotated, the two-phase pulses corresponding to the absolute code having many slit numbers are outputted from the converter 8 as a moving quantity. Therefore, the absolute position can be detected without mechanically returning to the original point by the simple constitution of the absolute type encoder. |
