| 摘要 |
PURPOSE:To obtain a stable output in any speed not to degrade the positioning precision by modulating the amplification factor of a servo amplifier on a basis of the result of comparison between a detected value from a rotation detecting means and a reference value from a rotation number reference value setting means. CONSTITUTION:The rotation number reference value of a DC servomotor 9 is set by fixed resistances 6 and 7. When the motor is rotated and the detected value outputted from a tachogenerator 10 exceeds the reference value, an LED is not driven, and a photodetector is in the open state, and the amplification factor of an operational amplifier 1 is the value of R1/R4. Meanwhile, if the detected value is smaller than the reference value, the photodetector is in the close state. At this time, the amplification factor of the amplifier 1 is the value of R1/{R4R5/(R4+R5)}. Where, R1 is the resistance value of a resistance 3. Thus, since a speed loop gain is changed larger than a conventional mechanism even if the feeding speed is very low, a torque gain is not reduced, and the responsiveness is not degraded.
|
