Image heating apparatus with movable rubbing member rubbing a heating rotating body

摘要

In an image heating apparatus in which a heating rotating body heats a recording material bearing an image and a rubbing member rubs the heating rotating body to eliminate gloss streaks, an image failure, such as gloss unevenness, does not occur on normal plain paper and coated paper, and a toner gloss on the coated paper can be enhanced. A longitudinal temperature difference of a heating rotating body 91 is controlled within a predetermined temperature, so that the surface of the heating rotating body can be uniformly roughed. Consequently, an image failure due to scuffs on the surface of the heating rotating body and gloss unevenness due to unevenness of roughness of the surface of the heating rotating body are prevented, and thus a good fixed image can be obtained.

主权项

1. An image heating apparatus, comprising:
a heating rotating body heating a toner image on a recording material at a nip portion; a rubbing member rubbing the heating rotating body; a moving mechanism moving the rubbing member from a position where the rubbing member is spaced apart from a surface of the heating rotating body to a position where the rubbing member rubs the heating rotating body; a first temperature sensor detecting a temperature of a first region of the heating rotating body through which the recording material having a conveyable minimum width in a width direction of the heating rotating body passes; a second temperature sensor detecting a temperature of a second region of the heating rotating body which is provided outside the first region of the heating rotating body and through which the recording material having a conveyable maximum size in the width direction of the heating rotating body passes; a controller executing an operation of moving the rubbing member to the position where the rubbing member rubs the heating rotating body when a number of the recording materials with a predetermined width conveyed to the nip portion reaches a predetermined number, and when a difference between the temperature of the first region detected by the first temperature sensor and the temperature of the second region detected by the second temperature sensor is more than a predetermined value in a case that the number of the recording materials with the predetermined width conveyed to the nip portion reaches the predetermined number, the controller executing the operation with a delay until the difference becomes equal to or less than a predetermined value; and a heat homogenizing unit smoothing the temperature distribution of the heating rotating body, wherein, when the difference is more than the predetermined value in the case that the number of the recording materials with the predetermined width conveyed to the nip portion reaches the predetermined number, the heat homogenizing unit is operated.