BELT CONVEYANCE DEVICE, FIXING DEVICE, AND IMAGE FORMING APPARATUS

To suppress the deformation of an end along the longitudinal direction of a belt, in comparison with a case where the curvature radius of the belt is equal in the end surface contact parts on the entrance side and exit side of a nip part.SOLUTION: A belt conveyance device includes a rotating endless belt, nip part forming means which comes into contact with the belt, to form the nip part, an inner peripheral surface contact part 495 which comes into contact with the inner peripheral surface of the belt, and holding means which has end surface contact parts 491a, b which at least come into contact with an end surface along the longitudinal direction of the belt on the entrance side and exit side of the nip part and end surface non-contact parts 497a, b which do not come into contact with the end surface along the longitudinal direction of the belt and holds the end along the longitudinal direction of the belt. In the belt, the curvature radius of a part coming into contact with the end surface contact part on the entrance side of the nip part is smaller than that of a part coming into contact with the end surface contact part on the exit side of the nip part.SELECTED DRAWING: Figure 8 【課題】ベルトの曲率半径がニップ部の入口側及び出口側の端面接触部で等しい場合に比べ、ベルトの長手方向に沿った端部の変形を抑制する。【解決手段】回転する無端状のベルトと、前記ベルトと接触してニップ部を形成するニップ部形成手段と、前記ベルトの内周面と接触する内周面接触部４９５、前記ベルトの長手方向に沿った端面と少なくとも前記ニップ部の入口側及び出口側で接触する端面接触部４９１ａ，ｂ、及び前記ベルトの長手方向に沿った端面と接触しない端面非接触部４９７ａ，ｂを有し、前記ベルトの長手方向に沿った端部を保持する保持手段と、を備え、前記ベルトは、前記ニップ部の入口側の端面接触部と接触する部位の曲率半径が、前記ニップ部の出口側の端面接触部と接触する部位より小さい。【選択図】図８