ES355111A1 - Carton forming machine - Google Patents

Abstract

A carton formed from the blanks shown in Fig. 18, i.e. two end panels E and a base B and sides S hinged thereto, is formed in a die-andplunger mechanism in which pre-glued flaps F i and F o are folded against the end panels E. The plunger 18 is operated by fluid pressure and as it begins to descend thrust members 22 thereon engage the upper edges of the side panels E and carry them down into engagement with the base B of the horizontally arranged blank. As the blank descends flaps F are folded up against panels E by a centre portion 154 of the cavity of the die and flaps F o are only partially folded up by folding plates 152 that are set back further from the centre line of the die than the portion 154. A valve 238 (Fig. 4) is next actuated and piston and cylinder devices 228 extended thereby rotating shafts 218 to cause arms 222 to fold up sides S against the vertical edges of panels E. An arm on one shaft 218 trips a switch 246 to operate a valve 203 whereby actuators 196, 198 move the U-shaped plates 152 inwardly, to completely fold up flaps F o against panels E. Since flaps F o are not pressed against panels E until panels S are vertical the glue on flaps F o is not smeared or wiped off. The stroke of the die is controlled by stops 110, 112 on plunger 18 and as the die commences to lift rollers 80 (Fig. 10) move up in inclined slots 82 thereby retracting the cross-sectional area of the die and releasing the carton. The carton does not fall immediately but is held by inwardly extended folding plates 152 which retract as the die nears its upper position. The carton then falls on to an outfeed conveyer. The blank comprising panels B and S has its flaps pre-glued and trips a switch as it reaches its position under the die to initiate the forming cycle. The machine can be adjusted to accommodate blanks of different sizes.