Tray former

Claim 1

In a machine for automatically setting up shipping trays from blank forms, the combination comprising: a magazine for storing a supply of said tray blanks for said machine; means for removing said tray blanks one at a time from said magazine; glue-applying means for selectively applying glue to predetermined portions of said tray blanks; indexing means for advancing tray blanks past said glue-applying means to a tray-forming station; and means disposed at the tray-forming station for folding the side panels of said tray at right angles to the tray bottom and successively folding the end flaps of one of said folded panels, the end fLaps of the other of said folded panels and the end flaps of said tray bottom in overlapping relation and at right angles to said folded side panels and said tray bottom, said tray-forming station comprising; a mandrel having a configuration substantially like that of the tray blank when set up, and being movably disposed in a reciprocable path perpendicular to the plane of said tray blank received at said tray-forming station, said mandrel being positioned to engage said tray blank on the bottom panel thereof upon movement in one direction; means on one side of said mandrel path for engaging a side panel of said tray blank and folding said side panel against the mandrel when said mandrel and said tray blank are moved thereby; means on the other side of said mandrel path for engaging the opposite side panel of said tray blank and folding said opposite side panel against the mandrel when said mandrel and said tray are moved thereby; a pair of flap folders disposed on said side panel engaging means for folding the end flaps of said side panel about the mandrel ends; another pair of flap folders disposed on said opposite side panel engaging means for folding the end flaps of said opposite side panel about the mandrel ends overlapping the flaps of said side panel; and means on the end sides of the mandrel path for engaging the end flaps of the tray bottom and folding said end flaps about the mandrel ends overlapping the folded end flaps of said opposite side panel; each of the flap folders which fold the end flaps of the side panels comprising; a mount having an opening therein; a flap arm pivotally disposed on said mount, said flap arm being alternately movable to one or the other of two positions and having a projecting cam surface at one end thereof movable in said opening in said mount when said arm is caused to move from one position to the other; and biasing means secured to said mount and said arm for alternately biasing said arm to one or the other of said two positions.