| 摘要 |
PURPOSE:To reduce running cost and to surely control the life of a drum unit by deciding whether the drum unit is new or old when it is mounted in a main body, rewriting a memory that it is already used and clearing a counter when the drum is new and continuously counting without clearing the counter when it has the history of use. CONSTITUTION:When the drum unit 1 is mounted in the main body 6, a control means 41 switches a power source device 20 to output a rated voltage to a fuse 10 and a decision means 30 judges whether the fuse 10 is normal or abnormal. In the case of judging that the fuse 10 is normal, the control means 41 switches the power source device 20 to overvoltage so as to cut out the fuse 10. Namely, a new memory stored by the drum unit 1 itself is rewritten that it is already used and the counter 9 is cleared as an initial condition for the new drum unit 1. In the case of judging that the fuse 10 is abnormal when the drum unit 1 is mounted in the main body 6, the counter 9 is not cleared. Therefore, the waste of paper and a large quantity of distinct printing are prevented. Thus, the running cost is reduced and the life of the drum unit is surely controlled. |
