Image forming apparatus

A sheet processing apparatus, comprising:

• a sheet conveyor configured to convey a sheet for processing;
• and
• a heating device configured to heat the sheet conveyed by the sheet conveyor, the heating device comprising:
• a cylindrical body configured to contact the sheet while the sheet is being moved past the cylindrical body in a sheet conveyance direction;
• a plurality of first heat generator elements in a first row along a first direction, the first heat generator elements being separated from one another in the first direction by a first gap;
• and
• a plurality of second heat generator elements in a second row spaced from the first row in a second direction intersecting the first direction, the second heat generator elements being separated from one another in the first direction by a second gap, wherein
• a center of each first gap is aligned to a center of one of the second heat generator elements;
• and
• a center of each of the second gap is aligned to a center of one of the first heat generator elements.

A fixing device, comprising:

• a pressure roller;
• and
• a heating roller configured to contact the pressure roller and apply heat to a sheet passing between the heating roller and the pressure roller in a sheet conveyance direction, the heating roller comprising:
• a first row of first heat generator elements along a first direction perpendicular to the sheet conveyance direction;
• a second row of second heat generator elements along the first direction, the second row being spaced from the first row in a second direction crossing the first direction;
• a plurality of first gaps between adjacent first heat generator elements in the first row;
• and
• a plurality of second gaps between adjacent second heat generator elements in the second row, wherein
• the first gaps are positions that do not overlap with the second gaps along the second direction, and
• the first and second heat generator elements are wired for independent control.