| 摘要 |
<P>PROBLEM TO BE SOLVED: To replace a component of an image forming apparatus at an appropriate timing with a minimum manual operation by a user, by preventing erroneous insertion of a replaceable unit, using a common circuit as a fresh item detection circuit and a power source rating detection circuit, and informing a user that a unit has reached the end of its life time and needs to be replaced. <P>SOLUTION: A fuse is mounted as the fresh item detection circuit for a replaceable unit, so that the fuse is melted when a fresh item is detected. When the fuse is melted, an amount of operation stored in a storage means is reset, and the amounts of operation are counted up by driving the unit. When the amount of operation reaches a prescribed value, a user is informed that the life time has reached its end. The time at which the fuse is blown is monitored when the fresh item is detected, the characteristic of a fixing unit, such as a rating voltage, can be detected by a time difference between this time and the time needed for the fuse to melt. In addition, likewise the case where the replaceable unit is replaced with a fresh one, a fuse is melted when the life time of the replaceable unit has reached its end. This makes it possible to recognize the degree of fresh state, the degree of used state, and the degree to which the life time has reached. <P>COPYRIGHT: (C)2007,JPO&INPIT |
