| 摘要 |
PURPOSE:To shorten the time required for the return of a carriage while maintaining noise at low level during the return of the carriage by comparing the pulse generated by a linear encoder with the pulse generated by a rotary encoder, and controlling a braking signal which is connected to a DC motor in accordance with the pulse rate. CONSTITUTION:A DC motor 31 is braked by energizing it in a reverse direction when a carriage 20 moves into the braking range. Then, after the lapse of a specified time, the pulse rate of a linear encoder 103 (LEP) is measured using CPU 200. Next, the pulse rate of a rotary encoder 101 (REP) is likewide measured, and these pulse rate are compared. Then if the result is that LEP is less than a setting value, it is judged that the travelling speed of the carriage becomes adequately low. And then the return action is terminated by further energizing the DC motor 31 in a reverse direction. In addition, if LEP is equal to or larger than the setting value, LEP is compared with REP. If these are equal, the DC motor 31 is energized in a reverse direction as the carriage 20 ad the DC motor 31 synchronously rotate. If LEP is larger than REP, the energization of the DC motor 31 in a reverse direction is shut off to perform a short braking action. |
