Apparatus and method to control media wrinkling through roll flaring

A method for reducing wrinkling of a print media in a printer having a belt for transporting the print media, a fuser roll, an internal pressure roll, and transport rollers for driving belt in a process direction, the method comprising:

• providing an internal pressure roll with flaring at each end, wherein the flaring causes the internal pressure roll to be substantially cylindrical over a central major portion thereof substantially corresponding to 25-75% of the width of the belt and flaring outwardly with increasing diameter at each end thereof;
• providing a plurality of transport rollers with flaring ends to define a path along which the belt is driven in a process direction, wherein the flaring causes each end of a plurality of transport to be substantially cylindrical over a central major portion thereof substantially corresponding to 25-75% the width of the belt and flaring outwardly with increasing diameter at each end thereof;
• forming a nip by contact between the belt and the internal pressure roll and contact between the belt and the external pressure roll;
• wherein the second member and plurality of rollers cause the belt to be larger in circumference at its ends then at its central major portion, inducing belt circumference strain causes a velocity profile that inhibits wrinkle of a print media on the outer surface of the belt as the print media passes through the nip.

A contact belt fusing apparatus with rollers to reduce print media wrinkling, the fusing apparatus comprising:

• an endless fusing belt having an external surface defining a path of movement;
• a plurality of support rollers for supporting and moving the endless fusing belt along the path of movement, the endless fusing belt as supported having a first fusing position centered axially on the plurality of support rollers at a first location, and at least a second fusing position centered axially on the plurality of support rollers at a second location spaced axially from the first location thereon;
• a heater to heat the external surface of the endless fusing belt;
• a pressure roller forming a fusing nip with the external surface of the endless fusing belt for contacting and moving therethrough the print media;
• and
• belt strain inducing flares at the pressure roller and plurality of support rollers to reduce wrinkling of the print media by inducing a strain on the endless fusing belt to causes a velocity profile that inhibits slip of the print media as the print media passes through the fusing nip.