A fixing device includes a cylindrical heat roller, a heating element, a pressure roller, and an auxiliary roller. The heating element is provided inside the heat roller and configured to apply heat to the heat roller. The pressure roller is configured to be pressed against the heat roller to form, with the heat roller, a nip area where a recording paper sheet is to be nipped. The auxiliary roller is provided inside the heat roller and configured to be pressed toward the pressure roller with a peripheral wall of the heat roller in between. An outer peripheral surface of the auxiliary roller pressed against an inner peripheral surface of the heat roller is formed into an inverted crown shape so that an outside diameter of the auxiliary roller gradually decreases from both axial ends of the auxiliary roller toward an axial center thereof.

A fixing device includes a belt having a tubular shape and extending in a longitudinal direction, and having a longitudinal end, a drive roller to rotate the belt to convey a print medium between the drive roller and the belt, a bushing located at the longitudinal end of the belt, and a guide wall adjacent to the bushing. The belt is displaceable in the longitudinal direction relative to the bushing. The bushing includes a shoulder adjacent to the longitudinal end of the belt and a stem extending from the shoulder to an inside of the belt to support the belt. The guide guides the bushing to move in a direction opposite to a conveyance direction of the print medium when the belt moves toward the bushing. The stem of the bushing includes a convex portion that is in contact with an inner surface of the belt when the belt is displaced in the longitudinal direction.

A belt conveyance apparatus includes a plurality of support rollers, an endless belt, a regulation portion configured to regulate a shift of the endless belt in a width direction, a regulation receiving member configured to contact the regulation portion to receive a regulation force by the regulation portion, and support members disposed on an upstream side, in a conveyance direction of the endless belt, of the support rollers provided with the regulation portion to oppose each other on an inner peripheral surface side and an outer peripheral surface side of the end portion side of the endless belt in the width direction, and configured to regulate a position of the regulation receiving member when the regulation receiving member enters a contact portion with the regulation portion.

An edge regulating member provided in a belt rotation device that tensions a belt via a belt tensioning roller and rotates the belt in a rotation direction includes a body that comes into contact with an inner surface of the belt and a regulating portion that extends, at a position adjacent to the body, further outward in a radial direction of the belt tensioning roller than the body, and comes into contact with an edge of the belt. Tension of the belt acting on the body while the inner surface of the belt is in contact with the body causes the regulating portion to tilt, turned outward in the rotation axis direction from a fold-back portion of the belt toward an upstream side in the rotation direction.

An image forming apparatus includes a first roller having a first portion between tapered portions, which are at each end of the first portion. An outer diameter of each tapered portion decreases with distance from the first portion along a width direction of the first roller. A second roller has a second portion facing the first portion of the first roller and third portions, which are at each end of the second portion. The third portions face the tapered portions of the first roller. A belt of the image forming apparatus has an inner surface contacting the first portion of the first roller and an outer surface forming a nip with the second portion of the second roller. The belt has a protruding portion on the inner surface at each end of the belt in the width direction. The protruding portions face the tapered portions of the first roller.

A flexible belt is disclosed for use in a printing system. The belt comprises an endless strip which, in use, travels along a continuous path. Formations are provided along the sides of the strip which are capable of engaging with lateral tracks to place the belt under lateral tension, the lateral tracks further serving to constrain the belt to follow the continuous path.

A flexible belt is disclosed for use in a printing system. The belt comprises an endless strip which, in use, travels along a continuous path. Formations are provided along the sides of the strip which are capable of engaging with lateral tracks to place the belt under lateral tension, the lateral tracks further serving to constrain the belt to follow the continuous path.

In a fixing device, a pressure unit is pressed toward a roller by an arm, to form a nip region. The pressure unit includes a belt configured to contact the roller in a nip region, a pressure pad configured to press the belt in combination with the roller, and a side guide including an end guide surface configured to guide a side end of the belt, and a stay configured to support the pressure pad. A supporting member is located on an outer side of the side guide that is opposite to an inner side on which the end guide surface faces. The supporting member is held between the stay and the arm, the supporting member comprising a contact surface which contacts the side guide and on which the side guide is swayably supported.

A fusing apparatus for an image forming apparatus includes a fusing belt having a sidewall that faces the fusing bel, a guide member, disposed on the sidewall and having a lower portion disposed above a lower portion of the bushing, and a ring member, disposed between the guide member and the fusing belt. The ring member can be deflected toward the sidewall in a gap which is provided below the lower portion of the guide member and between the ring member and the sidewall.

An imaging system comprises a pair of belt rollers to drive an endless belt along a belt path, the pair of belt rollers comprising a first roller and a second roller. A steering roller is located between the first roller and the second roller. The steering roller is tiltable to engage the endless belt. A wheel is located at an end of the first roller in abutment with an edge of the endless belt, to move along a rotation axis of the first roller, in an outward direction, when the endless belt shifts toward the wheel. A link mechanism transfers a movement of the wheel in the outward direction, to a tilting of the steering roller, in order to urge the endless belt to shift away from the wheel toward the belt path.