Devices for squaring tubular folding box blanks

Claim 2

In a device for squaring flat collapsed tubular blanks disposed upright in a horizontally extending stack of blanks, the device comprising primary lug elements marginally overlapping the foremost blank for retention of the blank at the end of the stack in a position in which the upper and the lower crease along which the blank is collapsed are substantially horizontal, a vacuum cup mounted for oscillation on an arc about a substantially horizontal axis parallel to said lower collapsing crease to grasp the forwardly facing panel of the foremost blank and draw the blank out of the grip of said primary lug elements, and a cam in advance of said lug elements over which cam said cup draws the lower collapsing crease thereby causing the blank to be squared as the said panel approaches a horizontal position, the improvement which comprises secondary lug means above said cam for engaging the blank adjacent its upper collapsing crease after the upper blank portion has escaped said primary lug elements, said cam and said secondary lug element engaging diagonally opposed portions of the parallelogram which the blank presents in side view.

Claim 3

A device according to claim 1 in which the secondary lug element is spaced from the plane of the foremost blank held by said primary lug elements by less than the expansion of the blank and more than one-half that distance.

Claim 4

A device according to claim 1 in which the secondary lug element is a bar.

Claim 5

In a device for squaring tubular folding box blanks in which a suction cup movable on an arc of substantially 90* about a substantially horizontal oscillating axis grasps the forwardly facing panel of the foremost blank of a substantially horizontal stack of blanks resting upright on the lower of the two creases along which the blanks are collapsed and draws the said foremost blank out of the grip of primary retaining elements which marginally overlap and normally retain the blank in an upright position and thereafter draws the said lower crease of the blank over a cam causing the blank to square, whereafter the squared blank is released by said cup with the said facing panel in a substantially horizontal position, the improvement which comprises a secondary abutment means forward of said primary abutment means in a position to engage the blank adjacent its upper collapsing crease after the upper portion of the blank is drawn by said cup out of said primary retaining elements.

Claim 6

In a device for squaring tubular folding box blanks in which a suction cup movable on an arc of substantially 90* about a substantially horizontal oscillating axis grasps the forwardly facing panel of the foremost blank of a substantially horizontal stack of blanks resting upright on the lower of the two creases along which the blanks are collapsed and draws the said foremost blank out of the grip of primary retaining elements which marginally overlap and normally retain the blank in an upright position and thereafter draws the said lower crease of the blank over a cam causing the blank to square, whereafter the squared blank is released by said cup with the said facing panel in a substantially horizontal position, the improvement which comprises a secondary abutment means forward of said primary abutment means in a position to engage the blank adjacent its upper collapsing crease after the upper portion of the blank is drawn by said cup out of said primary retaining elements.

Claim 7

In a device for squaring tubular folding box blanks in which a suction cup movable on an arc of substantially 90* about a substantially horizontal oscillating axis grasps the forwardly facing panel of the foremost blank of a substantially horizontal stack of blanks resting upright on the lower of the two creases along which the blanks are collapsed and draws the said foremost blank out of the grip of primary retaining elements which marginally overlap and normally retain the blank in an upright position and thereafter draws the said lower crease of the blank over a cam causing the blank to square, whereafter the squared blank is released by said cup with the said facing panel in a substantially horizontal position, the improvement which comprises a secondary abutment means forward of said primary abutment means above said cam at a distance from said cam less than the vertical dimension of the collapsed blank and more than the vertical dimension of the major panel of the blank, and at a distance from the foremost blank of the stack less than the dimension of the minor panel and more than one-half the dimension of the minor panel to engage the blank adjacent its upper collapsing crease after the upper portion of the blank is drawn by said cup out of said primary retaining elements.

Claim 8

In a device for squaring tubular folding box blanks in which a suction cup movable on an arc of substantially 90* about a substantially horizontal oscillating axis grasps the forwardly facing panel of the foremost blank of a substantially horizontal stack of blanks resting upright on the lower of the two creases along which the blanks are collapsed and draws the said foremost blank out of the grip of primary retaining elements which marginally overlap and normally retain the blank in an upright position and thereafter draws the said lower crease of the blank over a cam causing the blank to square, whereafter the squared blank is released by said cup with the said facing panel in a substantially horizontal position, the improvement which comprises a secondary abutment means forward of said primary abutment means above said cam at a distance from said cam less than the vertical dimension of the collapsed blank and more than the vertical dimension of the major panel of the blank, and at a distance from the foremost blank of the stack less than the dimension of the minor panel and more than one-half the dimension of the minor panel to engage the blank adjacent its upper collapsing crease after the upper portion of the blank is drawn by said cup out of said primary retaining elements.