| 摘要 |
PROBLEM TO BE SOLVED: To obtain a new power transformer for a telephone set to realize a low cost being in compliance with standards of a power supply system configuration relating to the telephone set resulting from tightened safety standards. SOLUTION: A bobbin 1 used for a telephone set power transformer 12 is structured by taking insulation and insulation distance into account where the bobbin 1 is partitioned into three coil frames by a plurality of flanges 5. A primary input coil 2 connected to a commercial power supply is wound on a coil part of the bobbin 1, a secondary output coil 3 is wound on an another part as a charging purpose and a secondary output coil 4 is wound on the other part as a telephone line purpose to enhance the insulation and the insulation distance among the coil 2-4. The secondary output coil 4 for the telephone line purpose acts like a supply power for a MODEM of a telephone set via a rectifier section and the MODEM directly connected to the telephone line keeps the insulation and the insulation distance. |
