| 摘要 |
<p>PURPOSE: To block inflow of a generating current at an early point of time and to advance the brake stop of an AC motor. CONSTITUTION: A rectifying circuit 100' comprises a first charge discharge circuit 100-1; a second charge discharge circuit 100-2; a comparator IC; and an FET.Q2. In a feed to an electromagnetic coil 7, capacitors C1 and C2 are charged. The charge voltages V1 and V2 of the capacitors C1 and C2 are compared with each other by a comparator IC. When a feed to an AC motor and a feed to the electromagnetic coil 7 are simultaneously cut off (AC simultaneous disconnection), the charge voltages V1 and V2 are reduced at a prescribed time constant. At a point of time when the V2 is reduced to a value lower than the V1 (after the lapse of 35ms), the output of the comparator IC is reduced to an L level, an FET.Q2 is turned OFF, inflow of a generating current from the AC motor to the electromagnetic coil 7 is blocked.</p> |
