Patent ID: 8948624
Filing Date: 2015-02-03
Classification: G03G

Abstract:
1. A fixing device comprising: a fixing roller; a single heating member that heats the fixing roller; a pressure roller that is pressed against the fixing roller; a first temperature detecting element that detects a temperature of a contact region, of the fixing roller, with which smallest sized paper used comes into contact; and a second temperature detecting element that detects a temperature of a noncontact region, of the fixing roller, that is outside a region with which largest sized paper used comes into contact, wherein energization control of the heating member is carried out based on a temperature detected by the first temperature detecting element, and energization control of the heating member is stopped when a temperature detected by the second temperature detecting element reaches a prescribed temperature, the fixing device further comprising a conduction shutoff portion that, in a case where the temperature of the contact region of the fixing roller has reached an upper limit temperature that is higher than the prescribed temperature, senses the upper limit temperature and shuts off the energization of the heating member, wherein, in a state in which a center position of the paper in an axial direction of the fixing roller has been aligned with a reference position of the fixing roller, the paper is transported sandwiched between the fixing roller and the pressure roller, and the first temperature detecting element and the conduction shutoff portion are arranged separated by a predetermined distance in a longitudinal direction along the axis of the fixing roller in a symmetrical manner with respect to the reference position.