| 摘要 |
<p><P>PROBLEM TO BE SOLVED: To control accurately temperature of a heating object by detecting infrared rays of the heating object with a simple structure. <P>SOLUTION: An infrared sensor 26 to detect infrared dosage irradiated from a heating object 20 outputs a detection signal of nearly constant size to the temperature of the heating object 20, when the temperature of the heating object 20 is less than a detection lower limit temperature, and outputs a detection signal in which the size and rate of increase of the detection signal becomes larger, the higher the temperature of the heating object 20 becomes, when the temperature of the heating object 20 is the detection lower limit or more. The control part 29, when the increase amount of the output value of the infrared sensor 26 to the initial detection value being the output value of the infrared sensor 26 immediately after heating start becomes a first prescribed value or more, reduces or stops output of a heating coil 21, and when the increase amount of the output value of the infrared sensor 26 becomes less than a second prescribed value smaller than the first prescribed value, increases the output of the heating coil 21, and corrects the first or/and the second prescribed values so as to make it smaller when immediately after heating start, a differential value of the infrared sensor 26 output value becomes large. <P>COPYRIGHT: (C)2010,JPO&INPIT</p> |
