| 摘要 |
PURPOSE: An operating coil control circuit is provided to achieve improved reliability and allow for ease of manufacture by enhancing circuit components into a digital system using a micro control unit. CONSTITUTION: An operating coil control circuit comprises a surge absorbing unit(2) for removing noises from the power input through an input terminal(1); a rectifier(3) for taking, as an input, the power from the surge absorbing unit, rectifying the power, and supplying a direct current voltage; a voltage divider(4) for taking, as an input, the direct current voltage from the rectifier, and dividing the voltage into low voltages; a first constant voltage unit(5) for taking, as an input, the direct current voltage from the rectifier, and generating a constant voltage; a second constant voltage unit(6) for taking, as an input, the constant voltage from the first constant voltage unit, and generating a constant voltage having a lower level; a control unit(7) for taking, as an input, the constant voltage from the second constant voltage unit and the divided voltages from the voltage divider, outputting a pulse width modulation signal if the power voltage is higher than the preset level of suction voltage, and outputting a release signal if the power voltage is lower than the preset level of suction voltage; an output driving unit(8) for taking, as an input, the pulse width modulation signal from the control unit and the constant voltage from the first constant voltage unit, and outputting a pulse width modulation signal of a higher voltage; a power switching unit(9) for controlling the voltage flowing in a coil in accordance with the signal output from the output driving unit; and a fly wheel unit(10) for absorbing the counter electromotive force remaining in the coil when the power switching unit is turned off.
|
