| 摘要 |
PURPOSE:To always execute a temperature control whose overshoot and ripple portion are small by setting again a control point temperature by the initial temperature of the vicinity of a control object, and executing on-off control. CONSTITUTION:When the power supply voltage of a heater is detected through a power supply voltage transducer 16 immediately after an electric power source is turned on, a control point temperature T1 based on detected voltage is stored in a storing circuit 4 by an output of a power-on time pulse generator 3 in case when the electric power source is turned on. When this signal sets time of a program timer 5 and a temperature becomes the control point temperature T1 by an operation of the timer 5, an H level is outputted to an AND circuit 7 from a pulse generator 6. On the other hand, an on-off controller 2 is set so as to be outputted up to a set temperature T0, therefore, after all, the on-off control is executed from the temperature T1 to T0. After reaching the temperature T0, the output is continued from the generator 6, therefore, basing on and off of the controller 2, the temperature is controlled to the set temperature. |
