| 摘要 |
PURPOSE:To eliminate the thermal overshoot which is caused by the rise control, by changing concurrently both the electric power to be applied to a heater and its application time during the rise. CONSTITUTION:The output voltage of a temperature sensor 7 is low in case when the temperature of a liquid is slightly lower than a target level. Accordingly the voltage which is supplied to a timer 12 and an electric power amplifier 13 from a differential amplifier 9 is set at a low level. As a result, the active time of the timer 12 is short. At the same time, the output power of the amplifier 13 is small, and the electric power to be supplied to a heater 17 is set at a low level. When the temperature of liquid is very low compared with a target level, the outputs of the sensor 7 and the amplifier 9 are set at a high level. Accordingly the active time of the timer 12 is long, and the output power of the amplifier 13 is set to a high level. As a result, the electric power to be supplied to the heater 17 is increased. |
