| 摘要 |
PROBLEM TO BE SOLVED: To control a flow rate with high accuracy without increasing power consumption in a water-quantity controller with a stepping motor. SOLUTION: A pulse generating section 7 forms the input pulses of pulse speed corresponding to target speed Vs required for controlling the speed of a stepping motor 13 based on a command from a driving-speed arithmetic section 5 when an output signal from a duty-timer driving section 9 is at an on level. When there is information that target speed Vs is changed from V2 to V1 or 0 to V1 from the arithmetic section 5, the on level and an off level are changed over at a duty ratio corresponding to the magnitude ofΔQ in the output signal from the driving section 9. The pulse generating section 7 sets the pulse speed of input pulses formed when the above-mentioned output pulse signal is at the on level on the basis of the command from the arithmetic section 5 and output to the motor 13 so as to be conformed to target speed Vs(=V1) after a change for one period of the above-mentioned output pulse signal. That is, even when the rotational speed of the motor 13 is kept in a low speed region, target speed Vs is set at V2 actually kept in a high speed region not at V1 kept in the low speed region. |
