Patent ID: 7466952

Claim:
A fixing device comprising a thermally fixing roller, an endless belt, and pushing means which pushes said belt toward the thermally fixing roller from the side of the inner peripheral surface of said belt such that part of the region in the circumferential direction on the outer peripheral surface of said belt is pushed onto part of the region in the circumferential direction on the outer peripheral surface of the thermally fixing roller, wherein a nipping region is formed between said part of the region of said belt and said part of the region of the thermally fixing roller that come in contact with each other, and said belt is driven when the thermally fixing roller is driven to rotate, wherein said part of the region of said belt is pushed by pushing means onto said part of the region of the thermally fixing roller in a manner that a pressure distribution is established in the circumferential direction of said nipping region, said pressure distribution producing a maximum pressure in an upstream end region of the thermally fixing roller in the direction of rotation in said nipping region, another maximum pressure in a downstream end region thereof in the direction of rotation in said nipping region, and a pressure in an intermediate region of said nipping region between said upstream end region and said downstream end region, which pressure is not higher than said maximum pressure in said upstream end region and not higher than said another maximum pressure in said downstream end region, and wherein said maximum pressure in said upstream end region in said nipping region is smaller than said another maximum pressure in said downstream end region.