Fixing Roller Thermal Capacity Layout for Stable Small-Sheet Heating

The patent applies local quality by creating a temperature gradient along the heating roller axis, with higher thermal capacity at the ends and lower at the center. This non-uniform thermal capacity distribution allows different axial regions to operate at different effective temperatures, preventing UFP generation at the ends while maintaining sufficient temperature for reliable fixing at the center region.

The heating roller incorporates a base body with varying thermal capacity along its axial direction, where the end portions have larger thermal capacity than the center portion. This local differentiation in thermal properties allows the center region to maintain higher temperature for reliable fixing while the end portions remain cooler to prevent ultrafine particle generation.

The patent changes the thermal capacity parameter of the heating roller base body along its axial direction. By designing the base body with larger thermal capacity at the end portions and smaller thermal capacity at the center portion, the system can process small-size sheets continuously at high productivity while preventing excessive temperature increase at the ends that would cause UFP generation.

The heating roller base body is designed with non-uniform thermal capacity distribution along the axial direction, where end portions have larger thermal capacity and the center portion has smaller thermal capacity. This local quality differentiation creates intentional thermal asymmetry that prevents excessive heating at the ends while maintaining overall thermal stability during continuous processing of small-size sheets.