| 摘要 |
The object of this invention is to provide a sheet guide unit for a sheet-fed press which will prevent the sheet from flapping or fluttering, and allow sheets of thinner paper to be conveyed smoothly even when a skeleton cylinder, which is better suited to thicker papers, for preventing the air streams exiting from both ends of the sheet guide surface from colliding with the frame and causing turbulence. The sheet guide unit according to this invention is provided under an intermediate cylinder or a delivery cylinder, and separated from the cylinders by a small sheet guide space for guiding the sheet. It has a curved sheet guide surface with which the lower surface of the cylinder creates the small sheet guide space, the space through which the air stream is directed; an air supply chamber which is behind the sheet guide surface; a plurality of air vents which vent air from the air supply chambers into the small sheet guide space, the air vents facing away from each other toward the sides of the cylinder on either side of its center line which vent air along the surface of the curved sheet guide surface along the width of the cylinder, so that the difference in the velocity of the air flow above and below the sheet being conveyed causes the sheet to be drawn toward the curved sheet guide surface andsuspended slightly above the curved sheet guide surface as the sheet is conveyed; a pair of air aspiration chambers provided adjacent to the air supply chamber on the outer sides of the cylinder into which the air is aspirated; and an air guide fin which is an outer extended portion of the curved sheet guide surface into the air aspiration chamber, and serves for directing the air into the air aspiration chamber. The volume of air drawn out from the air aspiration chambers on either side of the cylinder is larger than the volume of air aspirated into the air aspiration chambers, so that a negative pressure in the vicinity of the both ends of the sheet guide surface is created.
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