Patent ID: 8489006

Claim:
A fuser device for use in an electrostatographic reproduction apparatus, said fuser device comprising: a fuser roller, said fuser roller having a thick elastomeric cover; an external heater assembly, in operative association with said elastomeric cover of said fuser roller, said external heater assembly having a shaped tracking structure for an endless metal film defining a heating nip between the fuser roller and the endless metal film and a heating element to transfer heat rapidly to the endless metal film and to pressure the endless metal film against the external surface of said elastomeric cover of said fuser roller so that heat from the endless metal film diffuses into the elastomeric cover; and a pressure film belt assembly, including an endless pressure film belt in operative association with said fuser roller and spaced from said external heater assembly, and wherein said pressure film belt assembly has a pressure applicator which applies thermal contact and mechanical energy to define a nip pressure profile providing an extended fusing nip for said endless pressure film belt with said fuser roller, wherein the endless metal film has a thermal time constant that is less than a millisecond, so that temperature control for said fuser roller can be adjusted to provide a fusing temperature that provides high image quality for photos, text, and graphics for high quality reproductions with a determined gloss and wherein said pressure film belt assembly further includes an entrance roller, an exit roller, and the pressure applicator located with said pressure film belt to back up the pressure film belt assembly, wherein the pressure applicator is curved to approximately match the outer curvature of said cover of said fuser roller in the compressed, loaded state and a shape, stiffness, and load of the pressure applicator determines a pressure profile for a given fuser roller configuration.