Fuser nip release mechanism

#1. Field of the Invention

#The present invention relates generally to fusers and electrophotographic printing devices, and, more particularly, to release mechanisms that unload the nip formed by the pressure roll against the hot roll in the fuser.

#2. Description of the Related Art

#The above-mentioned and other features and advantages of this invention, and the manner of attaining them, will become more apparent and the invention will be better understood by reference to the following description of an embodiment of the invention taken in conjunction with the accompanying drawings, wherein:

#FIG. 1 is a schematic, fragmentary illustration of a printing device having a fuser nip release mechanism in accordance with the present invention, the fuser nip being shown in a loaded condition;

#FIG. 2 is an enlarged schematic, fragmentary illustration of the fuser nip in the printing device of FIG. 1, but illustrating the fuser nip in an open, non-loaded condition;

#Corresponding reference characters indicate corresponding parts throughout the several views. The exemplification set out herein illustrates one preferred embodiment of the invention, in one form, and such exemplification is not to be construed as limiting the scope of the invention in any manner.

#Referring now to the drawings and particularly to FIG. 1, there is shown an embodiment of a fuser module 10 in accordance with the present invention, suitable for use in an electrophotographic (E.P.) printing apparatus 12 shown in fragmentary form in FIGS. 3 and 4. Apparatus 12 further includes a machine frame 14, a fragment thereof which is schematically represented in FIG. 3. Fuser module 10 is removable from frame 14, as indicated by the dashed line in FIG. 3 interconnecting fuser module 10 and machine frame 14. A cover assembly 16 is pivotally connected to machine frame 14, and can be rotated between closed (FIG. 3) and opened (FIG. 4) positions. A linkage assembly 20 interconnects cover assembly 16 and components of fuser module 10, as will be described in further detail hereinafter. Apparatus 12 further includes other components of a print engine, media feed system and the like (not shown) which are well known to those skilled in the art and will not be described in further detail herein.

#Fuser module 10 includes a hot roll 22 in opposed relationship with a pressure roll 24. A path is defined between hot roll 22 and pressure roll 24 through which individual pieces of media pass during printing in printing apparatus 12. A combination of heat and pressure is applied to the media with toner thereon, for fusing and permanently affixing the toner particles to the media. Pressure roll 24 is loaded against hot roll 22 by a loading means such as a bell crank 26 and a spring 28. The manner in which a bell crank and spring are configured to apply pressure from a pressure roll 24 to a hot roll 22 is well known to those skilled in the art and will not be described in further detail herein, except as related to operation of a fuser nip release mechanism 30 in accordance with the present invention.