Sheet media handling system and printer having the same

#This invention relates to a sheet media handling system and a printer having the same for supporting both small and large width sheet media. More particularly, this invention relates to a sheet media handling system and printer having the same for presenting a large width sheet medium, that is partially supported by a stack of small width sheet media, substantially aligned to an infeed zone of the printer.

#Office equipment such as photocopiers, laser printers, ink jet printers and other imprinting mechanisms today incorporate an ability to receive sheet media from any one of two or more trays. It is very common to have a bypass tray in which a single sheet medium of a special type or of a different size can be conveniently fed for particular printing without having to load it onto pull-out trays.

#FIG. 1A shows one prior art media handling system having a pressure plate pivotably mounted on a base of a printer. During a pick cycle, the pressure plate is lifted to move a stack of sheet media located above it to an infeed zone of the printer. This pressure plate is usually designed to directly support a stack of sheet media in a main tray. During each pick cycle, the sheet at the top of the stack will be moved to the infeed zone. A simple and economical design of a bypass feeding system usually has a bypass tray positioned above the main tray. Sheet media in this bypass tray is supported either by the pressure plate itself (when there is no sheet medium in the main tray) or by a stack of sheet media in the main tray as shown in FIG. 1A. Such a design accords pick priority to any sheet medium in the bypass tray over that in the main tray. This design works well when the sheet media on both the bypass and main trays are of substantially the same width. When the media are of substantially the same widths, the sheet media in the main tray will be able to provide sufficient support for the sheet media in the bypass tray.

#The invention will be better understood with reference to the drawings, in which:

#FIGS. 1A and 1B are representative drawings showing a prior art sheet media handling system that includes a single pressure plate that is unable to provide adequate support of a larger width sheet media that is only partially supported by a smaller width sheet media thereunder;

#FIG. 2 is an isometric drawing of a portion of an ink jet printer having a sheet media handling system according to an embodiment of the present invention, the sheet media handling system has a first support and a second support that is biased by a biasing means;

#Hereafter, a preferred embodiment of the present invention will be described in the context of an ink jet printer having a main media tray and a bypass tray. However, it is to be understood that the invention is usable with any imprinting or sheet handling equipment that receives a larger width sheet media that is partially supported by a smaller width sheet media thereunder.

#FIG. 2 is an isometric view of a portion of an ink jet printer 2 with a sheet media handling system partially implemented in a pull-out tray 4. FIG. 3 is an isometric view of the pull-out tray 4. The printer 2 includes a bypass tray, generally indicated by a reference numeral 6, that is located above the pull-out tray 4. The pull-out tray 4 includes pivotably supported adjacent first and second supports 8, 10 (FIG. 3) that can be tilted largely independently of each other. The first support 8 however includes an engagement portion 9 (FIG. 4) which when allowed to do so engages the second support 10 to tilt the second support 10 together with the first support 8.

#Typically, the bypass tray 6 includes an exposed panel 12 on which sheet media may be placed, guided and supported by either the first and the second supports 8, 10 of the pull-out tray 4 or any sheet media supported thereon. The printer 2 has a pick mechanism 14 that defines an infeed zone, generally indicated by a reference numeral 16.