Abstract: Sheet feeding apparatus includes a relatively small number of horizontally adjustable suction cups distributed over the length of a feed opening. The suction cups are raisable to grasp the bottommost sheet in the stack at the most ideal position to assure removal of the sheet from the feed opening. Adjustable guide members align the corners of a stack of sheets above the feed opening. Each suction cup is fed from a separate pneumatic tube extending from a manually switchable control panel where a source of low suction pressure is selectively connectible to the suction cups in various connection combinations.

Abstract: Sheet feeding apparatus comprises suction cups which initially engages the bottom surface of a bottommost sheet in a stack of sheets, with the suction plane thereof parallel to the sheet. The suction cups are then raised a small distance where the cups are tilted in a direction away from a support ledge without any substantial horizontal movement thereof, and following which the suction cups are lowered to pull the front end of the bottommost sheet past the support ledge with a wiping contact and down upon the top and front portions of a drive roller. Adjustable suction cup position control apparatus is provided including a manually progressively adjustable member for varying the peak elevation reached by the suction cups. A stationary cam is provided against which a pivotable follower portion of a suction cup mounting member rides, to vary the inclination of the mounting member and the suctoin cups carried thereby as the elevation of the suction cups is varied.

Abstract: Sheet feeding apparatus for feeding sheet material one at a time from the bottom of a stack including a horizontal support for a stack of sheets, the horizontal support retaining a vertical stack of sheet material and terminating short of the front end of the stack providing a feed opening which exposes the front end portion of the bottom sheet in the stack. A support ledge for supporting the weight of the front end of the stack of sheets, confronts the feed opening. Suction cups engage the bottom surface of the exposed end portion of the bottommost sheet in the stack and pull the sheet downwardly from the stack through the feed opening. An upstanding front wall engages the front end of the stack of sheets. A movable ledge support has a resilient, flexible and adjustable lip projecting rearwardly into the feed opening from the front wall so that the degree to which the lip projects into the feed opening varies.

Abstract: Sheet conveyor apparatus for feeding sheets one at a time to a stop wall at the end of the conveyor with at least one overhead support extending above said conveyor. An overhead longitudinally adjustable roller carrying sub-assembly extends above the conveyor supported on the overhead support. The sub-assembly is comprised of a roller which engages a sheet of material moving on the conveyor and positioned to prevent "bounce back" thereof as the sheets are moved against the stop wall. The rollers are carried on resilient arms which may be adjusted to vary the downward force of the roller upon the sheet moving on the conveyor.

Abstract: Sheet feeding apparatus with an adjustable stack support in confronting relation to a feed opening able to accommodate sheets of various widths, so that one or more stacks of sheets can be supported along the feed opening with the longitudinal center line of any stack being positionable along different selected points along the length of the feed opening. At least about eight selectively controlled suction cups are aligned parallel to the length of the feed opening and encompass most of the opening engaging the bottom surface of the bottom sheet in any stack of sheets and withdraw the sheet from the stack. The spacing between contiguous margins of the suction cups is much less than about two diameters of each cup. The suction cups are preferably supported on the top of a pneumatic tube and are raised with the tube to engage the bottommost sheet in the stack. The pneumatic tube is mounted for pivotal movement upon a rockable carrier framework.

Abstract: Sheet feeding apparatus comprises longitudinally and laterally adjustable stacking members for retaining on a support tray one or more stacks of sheets to be fed from a feed opening exposing an end portion of the bottom sheet. Flexible spring lips form an adjustable width support ledge at the front of the feed opening which supports the front end of each stack of sheets. About 8 or more relatively closely spaced suction cups, encompassing the length of the feed opening and preferably supported on the top of a pneumatic tube, are raised with the tube to engage the bottom-most sheet in the stack. The pneumatic tube is mounted for pivotal movement upon a rockable carrier framework. The tube inclination and position relative to the sheet engaged by the suction cups are varied in a manner to ensure reliable removal of only one sheet at a time by the suction cups which pull the sheet with a wiping contact against the deflected ledge-forming spring lips.

Abstract: Pneumatic means are synchronously coupled to an offset machine or the like in order to positively separate and pull down the bottom sheet in a stack. Movement of the pneumatic means is synchronized with the movement of a pivotal roller that advances the pulled-down sheet onto a conveyor belt for delivery of the sheet to the utilization device. The sheet being fed is automatically aligned in a lateral direction by movable guide means that are synchronized with the feeding of the sheet. The forward edges of the lower most sheets on the stack are separated by a flow of air.