US Patent 7418229 Fusing unit that stabilizes a contact nip region

A fusing unit for fusing a nonfused toner image formed on a sheet medium, including: a heating roller; a pressing roller pressed to the heating roller; a heat-resistant belt which is wrapped around an outer periphery of the pressing roller and travels while being nipped at a nip portion between the pressing roller and the heating roller; a belt stretching member which stretches the heat-resistant belt; and a sliding member which is disposed between the belt stretching member and the pressing roller and slides along the outer periphery of the pressing roller, wherein the sliding member is disposed to be brought into contact with the heating roller through the heat-resistant belt at a contact portion.