Patent ES-358976-A1 (ES)
Title: Manufacture of bliss boxes
IPC: B31B50/62
Filed: 1968-10-09
Abstract: A Bliss box is formed from a body blank 10 comprising a bottom and two side walls and a pair of end wall blanks 11 by a machine comprising a supply bin at A for the blanks 10, adhesive applicators at B applying adhesive to the flaps of blank 10 and a folding and gluing apparatus at C where the body and end wall blanks are joined. The machine comprises a rigid framework 25 to which are secured two parallel elongated edge guide members for the blanks 10 having an adjustable spacing and supporting the side plates of the supply bin 40, a pair of glue dispensers 21 and a pair of vertical plate assemblies 105 for folding the blanks, so that the machine may be adjusted to accommodate blanks of different sizes. Body blanks 10 are removed from the bottom of the supply bin 40 through a gap in the front wall 56 by drive lugs 46 of a conveyer chain 45 and carried along the edge guide members 36 and support rails 48 beneath the glue applicators 21. Each glue applicator 21, Fig. 12, comprises a chamber 62 in which glue supplied via a cylinder 71 in stick or granulated form is melted, heat being supplied by a pair of resistance heating elements 73 controlled by a thermostat 75, and a reservoir 61 communicating with the chamber 62 by a passage 63 containing a gear pump 64. The lower end of the reservoir 61 is closed by a plate 77 having a plurality of boxes 83 in staggered relationship and in communication with a plurality of passages 80 also in staggered relationship such that each passage 80 communicates with three bores 83. The lower end of each passage 80 is closed by a spring loaded applicator ball 79 which is forced inwardly open on contact with the flaps of a blank. In a modification (Figs. 17a, 17b, not shown) the applicator ball 79 is replaced by a plunger (79a) having a ball head at the lower end with axial passages and an annular groove which communicates, in the open position, with the passage 80 and an auxiliary passage (84) between the groove and chamber 61. A pair of hold-down bars 92 situated centrally of the edge guide members 36 hold the body blank 10 firmly against the support rails 48 as it passes the glue applicators. Each hold-down bar has a cam face 94 at one end enabling it to ride over the blank and is pivotally connected at its other end to one end of an arm 88, 87 of adjustable length and in turn pivotally connected at its other end to the framework 25. The pivoted ends of the hold-down bars 92 have abutments 102 which prevent rebounding of a body blank 10 from a stop 100 and position it centrally of the folding and gluing apparatus. The folding and gluing apparatus comprises a mandrel 30 comprising four corner posts 155 adjustably connected adjacent their lower ends to a rectangular mandrel plate 150 which is vertically reciprocated by a crank-shaft connected to the plate by a rod 147. The corner posts 155 and four rods 151 attached to the mandrel plate are vertically slidably guided in adjustably positioned arms (166) and in pairs of bearing plates respectively which are mounted on the framework. As the mandrel descends, S-shaped pawls (130) on the corner posts 155 engage a pair of end blanks 11 in magazines 37 thrusting them downwardly to engage the body blank 10, the bottom flaps 14 of the blank 10 are folded upwardly by engagement with the central plates 168 of plate assemblies 105, rollers 23 mounted on the plate assemblies 105 fold up the sides of blank 10 and the side flaps 15 are pressed into contact with the blanks 11 by U- shaped pusher plates 169 reciprocated by a cam arrangement 203 into the same plane as plates 168. The completed box is discharged on to a conveyer 31. The conveyer chain 45, the gear pump 64, mandrel 30 and cam arrangement (203) are all driven by a motor 42 mounted on the framework 25.