| 摘要 |
<P>PROBLEM TO BE SOLVED: To prevent the influence of voltage drop by a reverse connection preventive diode at normal connection while inhibiting the ON of a relay switch at reverse connection of a power source. <P>SOLUTION: A relay coil 5 comprises coils A and B whose winding directions are the same, and one end P1 of the coil A is connected to a connector 2, and also the other end P2 is grounded via a transistor 12. One end P1 of the coil A and the other end Q2 of the coil B are connected with each other, and a diode 15 is provided between one end Q1 of the coil B and the other end P2 of the coil A. At normal connection, only the coil A is energized, but at reverse connection, the coil B is energized, too, and each component of magnetic flux of both coils negate each other, so that the relay 7 is not switched on at reverse connection. Since the diode 15 does not exist on the energization path of the coil A, it is not affected by the voltage drop by the diode at normal connection. <P>COPYRIGHT: (C)2007,JPO&INPIT |
