| 摘要 |
<p>PURPOSE:To feed envelopes automatically and smoothly, especially at the time of feeding a large quantity of sheets in a sheet feeder for picture image forming device such as a laser printer. CONSTITUTION:There is provided a spring 18 which supports an end fence 20 which pushes approximately ten envelopes from the top of a bundle 13 of envelopes plied up on a sheet bundle deck 10 for large quantity of sheets feeder, and an auxiliary bottom plate 17 which receives a bundle 13' of envelopes which is pushed by the end fence upward and makes the bundle 13' of envelopes come into pressure contact with the upper surface of a sheet feed roller 7, the spring repeats the operation whenever envelopes run out onto the auxiliary bottom plate. Because the bundle of envelopes on the auxiliary bottom plate is small, both the edges of the envelopes do not rise up even if envelopes are piled up, providing smooth sheet feed. In an ordinary sheet feed cassette, it is possible to prevent both edges of envelopes from rising by pressing down both edge parts of envelopes with the peripheral surface of an inclined cylindrical roller or a tapered roller which is provided with a horizontal shaft for smooth sheet feed. The sheet feed roller may be also used as the above purpose also, or used as a sub-roller provided installed in addition to the sheet feed roller.</p> |
