The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Oct. 07, 2003
Filed:
Jul. 12, 2001
Yoji Serizawa, Shizuoka, JP;
Canon Kabushiki Kaisha, Tokyo, JP;
Abstract
An image forming apparatus having a unit with a non-volatile memory provided in a toner cartridge. By controlling the method in which data is written to a non-volatile memory, data that has been rewritten in the memory due to malfunction can be restored. The apparatus includes a detector for detecting the amount of toner remaining in the cartridge. On the basis of this information, a memory controller writes data, which indicates that cartridge replacement is necessary, to a prescribed area of the non-volatile memory. A memory locking unit inhibits rewriting of this area once data has been written. If it is judged by the memory controller that rewriting of the data halted in mid-course, write-protect by the memory lock function unit is cancelled and rewrite is allowed to be completed again, after which rewrite is inhibited.