GB1170330A - Apparatus for Erecting Open Topped Trays from Blanks - Google Patents

Abstract

1,170,330. Erecting trays. BOWATER PACKAGING Ltd. 26 March, 1968 [13 Nov., 1967], No. 51644/67. Heading B5D. [Also in Division B8] A tray made from a blank having a bottom A, Fig. 3, side panels B, extension flaps D, end panels C, ledge panels E, outer glue flaps F, apertures H and tongues G, is erected by a reciprocating male former 40 pressing it down into an aperture defined by walls 5, 7 so causing the extension flaps D to be folded upwardly and inwardly by convex folding edges 26 of extension flap folding surfaces 25 (see also Fig. 5). At the same time the end panels C and ledge panels E are folded upwardly by inclined upper surfaces 36 of triangular blocks 30 (see top left quadrant, Fig. 3). The side walls B are then folded to lie outside the extension flaps D by upwardly and outwardly extending portions 13 of erecting plates 12. Each triangular block 30, Fig. 4, is connected to a support plate 22, both by an arm 31, pivoted on a rod 32, and by a coil spring 33 fixed to an L-shaped bracket 34. As the former 40 descends the blank strikes apices 35 of the blocks 30, causing them to pivot outwardly so completing the upwardly folding of the panels C, E. The glue flaps F then engage the convex folding edges 26 which, with curved and twisted slide plates 27, cause the flaps to be folded inwardly (see bottom left quadrant, Fig. 3). Further descent of the former 40 aligns fold lines J on the blank with the block apices 35, the fold lines now corresponding with the top edges of blocks 47, secured on top of the former 40. The blocks 30, being spring-biased, effect continual engagement of the ledge panels E by their apices 35, causing them to be folded inwardly and downwardly until arrested by inclined surfaces 49 on guides 48. Members 50 secured on the former 40 locate and prevent the tongues G being bent. The former 40 now ascends, causing the inclined surfaces 49 to fold back the ledge panels E until the former breaks free. The blocks 30 then spring back and re-fold the ledge panels E to lie at about 40 degrees to the vertical, the edges of the glue flaps F being vertical and the flaps themselves about 30 degrees to the side walls B. Downward pressure of a second blank causes the ledge panels E to become horizontal whilst opposed pairs of tapered, inclined plates 24 effect the contact of the glue flaps F and the side panels B. The tongues G of the erected tray now engage the apertures H of the next higher tray to effect stacking. The extension flaps D may be glued.