Media Sheet Guide Device and Method for Maintaining Proper Sheet Alignment in an Image Forming Machine

A media sheet guide device for maintaining sheet alignment in an image forming machine, comprising:

• an upper guide having a curved face;
• and
• a lower guide having a curved opening therein, said upper guide positioned within the curved opening, said upper and lower guides forming a curved path therebetween along which a sheet moves;
• said upper guide comprising:
• a body extending between spaced apart referenced edges of upstream and downstream media alignment mechanisms in said machine and having a face defining said curved path along which a sheet moves from the upstream reference edge to the downstream reference edge;
• a base of said body extending between the upstream and downstream reference edges;
• and
• a plurality of guide ribs formed on said base so as to define at least a portion of said face of said body, said guide ribs being laterally spaced apart widthwise of said base and having heights through which they protrude outwardly from said base, said guide ribs also having respective downstream end portions with curvatures extending lengthwise in the direction of the path and about which downstream end portions the sheet bends as the sheet approaches the downstream reference edge, selected ones of said downstream end portions of said guide ribs having at least one extension which protrudes outwardly from said guide rib end portions so as to modify said lengthwise extending curvatures thereof such that a differential drag is applied to the sheet that causes rotation of the sheet sufficient to displace a leading end thereof away from the downstream reference edge ensuring that a leading corner of the sheet may enter into the downstream reference edge without jamming against the downstream reference edge.