| 摘要 |
PURPOSE:To reduce the cost, the size and the weight by adding a capacitor and a resistor to a magnetic field generator circuit, thereby omitting a transistor for a switch. CONSTITUTION:A magnetic field generator applies a difference between the output of a command signal source 1 and the voltage of a current detecting resistor 10 through a comparator 2 to a control amplifier 3, and the output is applied to a control transistor (TR) 5. Negative electrodes of high and low voltage sources 8, 9 are connected, and a diode 7 and a resistor 12 of high resistance are connected to the connecting point. Further, a series circuit of a control TR5, a magnetic field generating coil 6 and a current detecting resistor 10 and a capacitor 11 are connected between the cathode of the diode 7 and the negative electrode of the source 9. Thus, when a command signal source 1 is given, an exciting current I is flowed to the coil 6 by the negative feedback operation due to the comparator 2 and the TR5. A high voltage for the quick magnetization is provided by a charged capacitor 11 to become a small current flowed through the resistor 12 in a flat top state. |
