Apparatus for separating sheets from a stack

Claim 2

Apparatus for separating sheets from a stack comprising a fixed hopper for a stack of sheets, means beneath said hopper for causing downward deflection of an end portion of the bottommost sheet in said stack, peeling means thereafter engageable with said deflected end portion for progressively peeling the remainder of the bottommost sheet from the bottom of the stack, a shuttle which has a transverse gap supporting the remainder of the sheet being peeled and supporting the other sheets in the stack during peeling, said peeling means including said gap for intercepting the deflected portion of the sheet, means for reciprocating said shuttle, belt means passing over and around said shuttle, said belt means having a portion secured in fixed position with respect to said hopper and above the shuttle while the shuttle is being reciprocated, and roller means on said shuttle rollably engaging said belt means to shift the latter from a position where the major portion of its length is beneath the hopper to a position where the major portion of its length is forwardly of said hopper, said means for causing downward deflection of an end portion of the bottommost sheet in the stack including a plurality of vacuum cups attached to said belt means and normally positioned under said end portion of said bottommost sheet and shiftable with said belt means.

Claim 3

Apparatus as claimed in claim 1 in which there are slots in said shuttle under the initial portion of the path followed by said vacuum cups as said shuttle is moved, a vacuum outlet for each vacuum cup communicating with the slot below, and a vacuum manifold below all of the slots in said shuttle whereby the vacuum cups grip said end portion of said bottommost sheet when the cups are over said slots.

Claim 4

Apparatus as claimed in claim 1 wherein the trailing edge of said shuttle is curved downwardly so as to cause said vacuum cups to move downwardly as the shuttle commences its motion, thereby deflecting said end portion of said bottommost sheet downwardly.

Claim 5

Apparatus for separating sheets from a stack comprising a hopper for a stack of sheets, means beneath said hopper for causing downward deflection of an end portion of the bottommost sheet in said stack, peeling means thereafter engageable with said deflected end portion for progressively peeling the remainder of the bottommost sheet from the bottom of the stack, a pair of shuttle sections connected for conjoint movement and having a transverse gap therebetween, said peeling means including said gap for intercepting the deflected portion of the sheet, means for reciprocating said shuttles horizontally below the hopper, rollers between each shuttle section and the bottom of the stack positioned to support the stack and prevent transmission of undesired moving forces from the shuttles to the bottom of the stack during movement of the shuttles, said means for causing downward deflection including vacuum cups carried by at least one of said shuttle sections and normally projecting from the upper portion and positioned for gripping engagement with an end portion of said bottommost sheet, said vacuum cups being mounted for oscillatory swinging movement to deflect said end portion of a sheet downwardly into said gap, means for applying a vacuum to said vacuum cups, valve means for terminating said vacuum when said end portion of said bottommost sheet is at a predetermined position within said gap, said vacuum cups being each mounted on the end of a tubular vacuum stem and said vacuum applying means including a vacuum manifold tube journalled near one end of said shuttle section adjacent the gap between shuttles, each of said vacuum stems being rigidly attached to said vacuum manifold tUbe, a rocker arm rigidly attached to one end of said manifold tube, a cam follower journalled to the end of said rocker arm, and a stationary cam plate positioned to act on said follower when said shuttle sections are reciprocated.

Claim 6

Apparatus for separating sheets from a stack comprising a hopper for a stack of sheets, means beneath said hopper for causing downward deflection of an end portion of the bottommost sheet in said stack, peeling means thereafter engageable with said deflected end portion for progressively peeling the remainder of the bottommost sheet from the bottom of the stack, a pair of shuttle sections connected for conjoint movement and having a transverse gap therebetween, said peeling means including said gap for intercepting the deflected portion of the sheet, means for reciprocating said shuttles horizontally below the hopper, rollers between each shuttle section and the bottom of the stack positioned to support the stack and prevent transmission of undesired moving forces from the shuttles to the bottom of the stack during movement of the shuttles, said means for causing downward deflection including vacuum cups carried by at least one of said shuttle sections and normally projecting from the upper portion and positioned for gripping engagement with an end portion of said bottommost sheet, said vacuum cups being mounted for oscillatory swinging movement to deflect said end portion of a sheet downwardly into said gap, means for applying a vacuum to said vacuum cups, valve means for terminating said vacuum when said end portion of said bottommost sheet is at a predetermined position within said gap, said vacuum cups being each mounted on the end of a tubular vacuum stem and said vacuum applying means including a vacuum manifold tube journalled near one end of said shuttle section adjacent the gap between shuttles, each of said vacuum stems being rigidly attached to said vacuum manifold tUbe, a rocker arm rigidly attached to one end of said manifold tube, a cam follower journalled to the end of said rocker arm, and a stationary cam plate positioned to act on said follower when said shuttle sections are reciprocated.

Claim 7

Apparatus for separating sheets from a stack comprising a fixed hopper for a stack of sheets, a shuttle mounted for movement below said hopper and having a transverse gap therein, belt means having opposite loop portions forming an anti-friction support for the sheets of the stack extending over and around said shuttle and having a portion secured in fixed position above the shuttle and adjacent the hopper, means connected with said shuttle and responsive to movement of the shuttle for causing downward deflection of an end portion of the bottommost sheet in the stack into said transverse gap, roller means in each of the opposite loop portions of said belt means, and means for reciprocating the shuttle in a direction to cause the roller means to shift the belt means from a position where the major portion of the length of the belt means is beneath the hopper to a position where the major portion of its length is forwardly of the hopper, said means for causing said downward deflection comprising suction cups mounted on said belt means for shifting movement with the belt as the belt means is shifted.

Claim 8

Apparatus for separating sheets from a stack comprising a fixed hopper for a stack of sheets, a shuttle mounted for movement below said hopper and having a transverse gap therein, belt means having opposite loop portions forming an anti-friction support for the sheets of the stack extending over and around said shuttle and having a portion secured in fixed position above the shuttle and adjacent the hopper, means connected with said shuttle and responsive to movement of the shuttle for causing downward deflection of an end portion of the bottommost sheet in the stack into said transverse gap, roller means in each of the opposite loop portions of said belt means, and means for reciprocating the shuttle in a direction to cause the roller means to shift the belt means from a position where the major portion of the length of the belt means is beneath the hopper to a position where the major portion of its length is forwardly of the hopper, said means for causing said downward deflection comprising suction cups mounted on said belt means for shifting movement with the belt as the belt means is shifted.

Claim 9

Apparatus for separating sheets from stacks comprising first and second longitudinally-spaced hoppers each having forward and rearward ends, each for a stack of sheets, first and second shuttle sections, one normally positioned beneath each hopper, with said sections connected for conjoint movement and there being a transverse gap therebetween, means on each shuttle section forming an anti-friction support for the sheets of the stack, means connected with said shuttle and responsive to movement of the shuttle for causing downward deflection of an end portion of the bottommost sheet in the stack into the gap between shuttle sections, and means for reciprocating the shuttle in a direction to cause the anti-friction support of the first shuttle section to shift from a position where the major portion of its length is beneath the first hopper to a position where the major portion of its length is forwardly of said first hopper, with the anti-friction support of the second shuttle section shifting from a position beneath the second hopper to a position beneath the first hopper to support the stack of said first hopper.

Claim 10

Apparatus for separating sheets from stacks comprising first and second longitudinally-spaced hoppers each having forward and rearward ends, each for a stack of sheets, first and second shuttle sections, one normally positioned beneath each hopper, with said sections connected for conjoint movement and there being a transverse gap therebetween, means on each shuttle section forming an anti-friction support for the sheets of the stack, means connected with said shuttle and responsive to movement of the shuttle for causing downward deflection of an end portion of the bottommost sheet in the stack into the gap between shuttle sections, and means for reciprocating the shuttle in a direction to cause the anti-friction support of the first shuttle section to shift from a position where the major portion of its length is beneath the first hopper to a position where the major portion of its length is forwardly of said first hopper, with the anti-friction support of the second shuttle section shifting from a position beneath the second hopper to a position beneath the first hopper to support the stack of said first hopper.