International Business Machines Corporation

Charles E Peterson

Earl G Edwards

Leon C Brown

Michael R Headrick

Clement C Wilson

Peter G Robinson

An apparatus which provides for a constant center distance between all drive components in a hot roll fusing assembly during fusing nip opening/closing. This apparatus includes a roll closure device which utilizes a high mechanical advantage toggle mechanism in conjunction with a cam drive. The toggle mechanism is comprised of a pivot arm pinned to the fuser frame and a force-cell attached to the pivot arm and the shaft through the backup roll. The backup roll is constrained to rotate about the cam shaft. When the cam rotates, it rotates the pivot arm, which in turn drives the backup roll either towards or away from the hot roll while maintaining a constant center distance between the backup roll center line and a center line through the cam shaft. The drive means for the backup roll includes a first gear drivingly coupled thereto which rotates on the same axis and which meshes with a second gear rotating on the same shaft as the cam. Thus, with power input at the cam shaft, the backup roll is driven with minimum backlash by gears whose center distance is constant regardless of backup roll position.

Hot roll fuser roll closure apparatus

Apparatus in a copier fusing assembly for distributing the wear on a hot roll occasioned by the use of variable length copy sheets. This wear is distributed over the horizontal length of the hot roll by reversing the hot roll, end-for-end. Easy reversal of the hot roll is made possible by utilization of a hot roll subframe which is removably mounted in the copier fuser mainframe. A hot roll handle on the subframe allows for manual removal of the subframe and hot roll from the mainframe and out of the copier where they are reversed and inserted back into the mainframe. Operation of a latch handle moves a sheet detach bar and sheet transport exit-ways away from the downstream side of the fusing nip to facilitate jam clearance.

Apparatus to facilitate jam recovery and hot roll reversal in a fusing

An electrophotographic copier having a hot roll fuser assembly. This assembly is slidably supported by a pair of rails. When the fuser assembly is locked into its fusing position, within the copier, it is relatively inaccessible for purposes of inspection, cleaning and/or jam clearance. In its withdrawn, inoperative position, a single manually operable jam clearance handle is operator accessible. Manual actuation of this handle, from a folded to an extended position, is effective to move both a sheet peeler or detach bar, and a sheet transport channel away from the fusing nip. When the handle is moved back to its folded position, the sheet detach bar and transport channel are accurately positioned, and locked in an operative position closely adjacent to the downstream side of the fusing nip, so as to aid in release of the sheet from the fusing nip, and to guide the sheet away from this nip.

Growing community of inventors

Boulder, CO, United States of America

Charles E Peterson