Fixing device and image forming apparatus incorporating same

A fixing device for fixing a toner image on a recording medium, comprising:

• an endless belt-shaped fixing member rotating in a predetermined direction of rotation, formed into a loop;
• a nip formation member provided inside the loop formed by the fixing member;
• a pressing member provided outside the loop formed by the fixing member to apply pressure to the nip formation member to press the fixing member against the nip formation member to form a nip between the pressing member and the fixing member through which the recording medium bearing the toner image passes;
• a laminated heater facing an inner circumferential surface of the fixing member to heat the fixing member;
• and
• a heater support provided inside the loop formed by the fixing member between the laminated heater and the nip formation member, to support the laminated heater at a position opposite the nip formation member via an axis of the fixing member in a state in which the laminated heater is provided between the fixing member and the heater support;
• and
• a core holder provided inside the loop formed by the fixing member between the nip formation member and the heater support, and supported by a frame of the fixing device at lateral ends of the core holder in an axial direction of the fixing member, the core holder having a predetermined width in the axial direction of the fixing member to support the nip formation member and the heater support.