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:
Aug. 01, 2000
Filed:
Feb. 10, 1998
Canon Kabushiki Kaisha, Tokyo, JP;
Abstract
In order to separately detect an abnormal temperature rise at a fixing roller of an image forming apparatus and a disconnection of a thermistor that detects the temperature of the fixing roller, the first and the second resistors are selected and connected to a thermistor for predetermined periods of time. When the first resistor is connected to the thermistor, a disconnection of the thermistor is detected based on a detection voltage that corresponds to the voltage division ratio of the reading for the first resistor to the reading for the thermistor. When the second resistor is connected to the thermistor, an abnormal temperature rise of the fixing roller is detected based on a detection voltage that corresponds to the voltage division ratio of the reading for the second resistor to the reading for the thermistor.