| 摘要 |
<p>PURPOSE:To facilitate speed setting of high and constant speeds with one variable resistor by adding a circuit consisting of series connection with a variable speed for speed setting, a fixed resistor connected in series with the variable resistor, and the series connection of a fixed resistor and a speed changeover switch in parallel with the former fixed resistor to a motor speed control circuit. CONSTITUTION:Resistors 8, 10 are considered as a combined resistor, a proper resistance is decided to provide the number of revolutions at the constant speed when a switch 12 is turned on and the number of revolutions at the constant speed is set by a variable resistor 9. When the switch 12 is turned off, the high speed setting is executed. That is, since the resistance value of the variable resistor 9 is set, the resistance value of the resistor 8 is decided necessarily. Since the resistors 8, 11 have a resistance value in matching with the constant speed number as the combined resistance, when the resistance value of the resistor 8 is decided, the resistance of the resistor 10 is decided by calculation. Thus, high speed is obtained by turning off the switch and a constant speed is obtained by turning on the switch.</p> |
