Fixing device and image forming apparatus

An image forming apparatus comprising a fixing device, wherein the fixing device includes:

• a fixing member configured to be rotatable and provided with a sheet passing region through which a recording medium is passed and a non-sheet passing region arranged outside the sheet passing region;
• a pressing member configured to come in pressure-contact with the fixing member to form a fixing nip;
• and
• a separating member configured to separate the recording medium passed through the fixing nip from the fixing member, the separating member including
• a separating plate facing the sheet passing region with an interval and
• a restricting piece configured to contact with the non-sheet passing region and to restrict the interval between the sheet passing region and the separating plate, and provided with a curving surface on a region including the contacting portion with the non-sheet passing region,
• wherein the curving surface has
• a first curving area provided on a downstream side from the contacting portion in a rotating direction of the fixing member;
• and
• a second curving area provided on an upstream side from the contacting portion in the rotating direction of the fixing member and having a radius of curvature larger than that of the first curving area.