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Buffer/Flipper with optional urge unit for continuous form printers Disclosure Number: IPCOM000013683D
Original Publication Date: 2001-Apr-16
Included in the Prior Art Database: 2003-Jun-18

Publishing Venue



Disclosed is a device that uses a combination of forced air and Venturi effect suction in the buffer/flipper station to aid in cooling the continuous forms coming out of the printer and to keep the forms from sticking to the rollers. Additionally, an optional urge unit configuration on this buffer/flipper provides assistance for paper movement, reducing the possibility of jams. In the buffer/flipper unit, compressed air is forced through holes in the rollers against which the printed side of the paper lies, to discourage sticking and drag. The air against the paper encourages cooling for heated fused forms. Rollers which have the printed side of the page facing away incorporate a Venturi effect, achieved by grooves machined into the rollers. Cooling is also faciltitated by the air flow from the Venturi effect. The Venturi effect rollers use open or vaned ends to allow air flow out of the roller. When an urge unit configuration is used with the buffer/flipper invention, some or all of the rollers may be driven. A preferred embodiment drives some or all of the rollers utilizing the Venturi effect, since the Venturi effect holds the paper against the rollers, while motion of the rollers assists the paper through the buffer/flipper and reduces drag. The result is a reduced occurrence of paper jams. A preferred embodiment drives the rollers at medium RPM but very low torque, so that paper stoppage (such as with job stoppage) is sufficient to cause the driver to clutch. This reduces the cost of the driver, its peak current, and is also desirable for leaving slack between engines when printing stops. Ideally, no air should be fed to the buffer/flipper during threading, to make threading easier (the paper will not move away from the rollers as much while the operator is threading.) Air should be fed during printing, and also during temporary job stoppage: it is the delay during temporary stoppage that leaves hot printed forms against the rollers for several seconds until the engine restarts, increasing the chance of sticking and forms jam when printing restarts. Increased air pressure through the rollers during temporary stoppage would discourage sticking and help to cool the forms. Alternatively, the air (and optional urge driving) could be controlled by the operator; however, the operator would need to be instructed to leave the air on during temporary print stops that leave fused images in the buffer/flipper between print engines in a multiple-engine configuration. In either case, causing urge unit drivers for the buffer/flipper to be disabled when the compressed air is disabled will extend motor life. 1