Image heating apparatus and image forming apparatus

摘要

An image heating apparatus includes an image heating member configured to heat an image on a recording medium, a heat source heating the image heating member from an inside thereof, an image heating temperature detecting member detecting the surface temperature of the image heating member, an external heating member heating the image heating member from an outside of the image heating member, a cooling fan cooling a surface of the image heating member, and a control portion. The control portion is configured to execute a first mode of controlling the temperature detected by the image heating temperature detecting member under a predetermined control condition to a target temperature while executing a preceding job and a second mode of switching the predetermined control condition while maintaining the setting of the target temperature while processing the preceding job.

主权项

1. An image heating apparatus comprising:
an image heating member configured to heat an image on a recording medium; an image heating temperature detecting member detecting a surface temperature of the image heating member in contact with the image to be heated; a first temperature adjustment portion adjusting the surface temperature of the image heating member from inside of the image heating member; a second temperature adjustment portion adjusting the surface temperature of the image heating member from outside of the image heating member; and a control portion controlling the first and second temperature adjustment portions and configured to execute a temperature adjustment Down preliminary control operation in the middle of heating of a plurality of first recording media in a case of heating a second recording medium whose basis weight is smaller than that of a first recording medium of the plurality of the first recording media in succession after heating the plurality of first recording media, the control portion executing the temperature adjustment Down preliminary control operation, while maintaining a setting of a target temperature of the surface temperature detected by the image heating temperature detecting member at a target temperature corresponding to the first recording medium, by reducing the quantity of heat supplied from the first temperature adjustment portion to the image heating member and by controlling the second temperature adjustment portion such that the surface temperature detected by the image heating temperature detecting member is adjusted to the target temperature corresponding to the first recording medium.