Belt-type fixing device and image forming apparatus using same

An image forming apparatus comprising:

• an image forming device to form a toner image on a recording medium;
• and
• a fixing device to fix the toner image on the recording medium,
• the fixing device comprising:
• an endless, loop-shaped, flexible fixing member;
• a supporting member having a pipe shape disposed inside a loop formed by the fixing member to support the fixing member;
• a pressing member disposed opposite the supporting member via the fixing member;
• and
• a nip formation member disposed opposite the pressing member via the fixing member to form a fixing nip between the fixing member and the pressing member,
• the fixing member disposed to contact an outer circumferential face of the supporting member at a side opposite a side at which the fixing member contacts the nip formation member at the fixing nip,
• the fixing member driven in accordance with rotation of the pressing member to convey the recording medium to the fixing nip,
• the fixing member having slack portions formed upstream and downstream from the fixing nip in a conveyance direction in which the recording medium is conveyed, the slack portions extending toward the pressing member over the fixing nip without contacting either the supporting member or the pressing member.