| 摘要 |
PURPOSE:To control starting and stopping with high accuracy by counting with a counter the output pulse width of a digital encoder and comparing the counting with a target value that is renewed by a certain time and D/A converting the counting and controlling the motor. CONSTITUTION:The output pulse width of a digital encoder 2 that is provided on a motor 1 for feeding tape for cartridge magnetic tape devices, etc. is counted by a counter 3 and the counting is input to a calculation circuit 5 through a latch 4. On other hand a counter 8 counts the time from instruction by the output of a control section 9 that receives travel instruction and by the output of the counter 8 succeeding target values are output successively and the outputs are input to a calculation circuit 5 through a resistor 6, and the difference from the content of the latch 4 is calculated and supplied to a D/A converter 10 to control the drive of the motor 1. Accordingly by comparing with the target value that is renewed in a certain time the control of starting and stopping can be carried out with high accuracy and with an inexpensive constitution. |
