| 摘要 |
<p>A sheet feeder employing a vacuum feed belt in conjunction with a vacuum control plenum immediately adjacent the downstream edge of the vacuum belt, a self actuating valve being provided to shut off the vacuum supply to the feed belt when the sheet being fed blocks the openings in the control plenum to prevent acquisition of a second sheet by the feed belt until the trailing edge of the sheet being fed clears the control plenum.</p> |
