Fixing device and image forming apparatus

A fixing device comprising:

• an endless belt configured to fix toner onto a recording medium using heat;
• a heating member comprising a sheet that has flexibility and that is configured to heat the belt from inside a space enclosed by the belt;
• and
• a stationary member including:
• a curved surface that is in contact with the heating member;
• a fixed area of the curved surface at which the heating member is fixed to the stationary member;
• and
• a non-fixed area of the curved surface at which the heating member is not fixed to the stationary member,
• wherein the stationary member has a coefficient of linear expansion different from a coefficient of linear expansion of the heating member,
• wherein the belt is wound around the stationary member via a layer that includes the heating member,
• wherein rigidities of the belt and the heating member are lower than a rigidity of the stationary member,
• wherein the belt is configured to rotate in a specific direction, and
• wherein the non-fixed area is positioned more downstream than the fixed area in the specific direction.

A fixing device comprising:

• an endless belt configured to fix toner onto a recording medium using heat;
• a heating member comprising a sheet that has flexibility and that is configured to heat the belt from inside a space enclosed by the belt;
• and
• a stationary member including:
• a curved surface that is in contact with the heating member;
• a fixed area of the curved surface at which the heating member is fixed to the stationary member;
• and
• a non-fixed area of the curved surface at which the heating member is not fixed to the stationary member,
• wherein the stationary member has a coefficient of linear expansion different from a coefficient of linear expansion of the heating member,
• wherein the belt is wound around the stationary member via a layer that includes the heating member,
• wherein rigidities of the belt and the heating member are lower than a rigidity of the stationary member,
• wherein the belt is configured to rotate in a specific direction, and
• wherein the fixed area includes an end portion of the heating member on an upstream side in the specific direction.