Fixing device and image forming apparatus

A fixing device corresponding to a plurality of sheet passing widths in a direction orthogonal to a conveying direction of a sheet type recording medium, the fixing device comprising:

• a rotating member configured to convey the sheet type recording medium, rise in temperature, and fix toner;
• a plurality of temperature sensors configured to detect a surface temperature on an outer side of the rotating member;
• a plurality of heating members having a line shape, each partially including at least one heat generating unit, the plurality of heating members being provided inside the rotating member in parallel with a rotation axis of the rotating member;
• and
• a control unit configured to control a heating state obtained by the plurality of heating members, wherein
• the heat generating units in the plurality of heating members are provided so as not to overlap with each other in the direction of the sheet passing width orthogonal to the conveying direction of the sheet type recording medium,
• the plurality of temperature sensors are placed at positions corresponding to the heat generating units used when printing on the sheet type recording medium having a minimum sheet passing width, and are not placed at positions corresponding to the heat generating units adjacent to the heat generating units used when printing on the sheet type recording medium having the minimum sheet passing width, and
• the control unit controls the heating state obtained by the plurality of heating members in accordance with the surface temperature, the sheet passing width, and an operational state of the rotating member that changes with time.