| 摘要 |
PURPOSE:To certainly stop the heating to a small material such as a can and prevent the danger by excessive heating by correcting the output of an input current detecting circuit to form the same rising curve as the output of a voltage detecting circuit. CONSTITUTION:By a correcting circuit 12 formed of resistors 13, 14, 15 and a Zener diode 16, the output of an input current detecting circuit 7 is approximated to the output characteristic of a voltage detecting circuit 8 as the output characteristic approximate to the primary function obtained by combining two secondary curves. The outputs of the input detecting circuit 7 and the voltage detecting circuit 8 are mutually compared to judge whether a load can be heated or not by a small material judging circuit 9, and a switching element 4 is operated. Even if the heating output is increased, the output of the input current detecting circuit is never suddenly increased, heating can be certainly stopped regardless of the heating output in the case of a small material such as a can to prevent excessive heating, and safety can be enhanced. |
