| 摘要 |
<P>PROBLEM TO BE SOLVED: To detect the trouble of an impedance change type humidity sensor. <P>SOLUTION: The CPU 121 of a copier is functionally equipped with a first voltage generating part 121a for generating first voltage of which the polarity is a positive rectangular wave, a second voltage generating part 121b for generating second voltage of which the polarity is a negative rectangular wave, a humidity measuring part 121c for measuring humidity by applying the first voltage to one end of the humidity sensor while applying the second voltage to the other end of the humidity sensor through a first resistor and measuring the first detection voltage being the voltage generated across both ends of the first resistor and a judge part 121d for judging the trouble of the humidity sensor on the basis of the value determined by applying the first voltage to one end of the humidity sensor in the case where the first voltage satisfies a predetermined condition and earthing the other end of the humidity sensor to measure second detection voltage being the voltage generated across both ends of the first resistor. <P>COPYRIGHT: (C)2007,JPO&INPIT |
