Reusable unit displaying a specific pattern and an image forming apparatus using the reusable unit when the specific pattern is displayed and rendering the specific pattern illegible when the reusable unit is exhausted

摘要

An identification label is affixed on a top surface of an image forming unit which is detachably installed in a main component of an image forming apparatus. The identification label is made of a thermosensitive paper on which a trademark logo is printed. A logo reader in the main component reads a pattern of the logo mark on the identification label. A control unit compares the read logo pattern with a previously stored pattern to discriminate whether the read logo mark is genuine or not. If the identification label has the genuine logo mark, the control unit executes printing. If the identification label has an irregular logo mark, printing is abandoned and an error message is displayed. When a genuine image forming unit is exhausted, the control unit controls a heating device to apply heat to the identification label in order to wholly or partially discolor the identification label so that the logo mark is transformed to unreadable one. That unit will be regarded as an irregular one thereafter. For authorized activity for reusing such treated unit, a newly prepared genuine label is affixed to the once exhausted image forming unit after refilling toner or replacing a photoconductor drum is done.