BOX ERECTING MACHINE AND METHOD
FIELD OF THE INVENTION
This invention relates to a box erecting machine and to a method of erecting a box.
BACKGROUND TO THE INVENTION
A box known as a Bliss box is generally made of a body blank and two panels. The panels are secured to either side of the body blank to form the Bliss box. Bliss boxes are described in US patents 1,697,709; 1 ,974,527 and 4,948,033.
Various different types of Bliss box erecting machines have been developed over the years. Current Bliss box erecting machines fold the body blank into a "U" shape, and secure the two panels to the folded body blank against a mandrel.
It is an object of this invention to provide a machine and a method for erecting boxes, and more particularly, but not exclusively, for erecting boxes described in PCT/I B01/00997 and in PCT/IB03/00712.
SUMMARY OF THE INVENTION
According to the invention a machine for erecting a box from a body blank and two panels includes:
body blank and a panel securing means for securing the two panels to opposite sides of the body blank; and
box folding means for folding the body blank and the two panels secured to the body blank into a box.
The machine preferably includes conveying means for conveying the body blank with the two side panels secured to it from the body blank and panel securing means to the box folding means.
The machine preferably includes pillar forming means for forming at least one pillar in each of the panels before the panels are secured to the body blank.
The machine may include inserting means for inserting bracing means into the box to extend between the pillars formed in opposed panels.
The machine may include bending means for bending free ends of the bracing means at substantially right angles to the remainder of the bracing means so that the bent free ends can be secured to the panels.
The folding means preferably includes a mandrel.
The machine preferably includes adhesive applying means for applying adhesive to the body blank so that the panels and the body blank can be secured together by the securing means.
The machine preferably includes a body blank hopper and two panel hoppers, the body blank hopper and the two panel hoppers being located upstream of the box folding means.
According to another aspect of the invention a method of erecting a box includes the steps of:
providing a body blank and two panels;
securing the panels to opposite sides of the body blank; and
folding the body blank and the panels secured to the body blank into a box.
The method preferably includes the step of securing the panels to opposite sides of the body blank whilst the body blank and the panels lie in substantially the same plane.
The method preferably includes the step of forming at least one pillar in each of the panels before the panels are secured to the body blank.
The method may include the step of inserting bracing means into the box to extend between the pillars formed in the panels.
The method may include the step of bending free ends of the bracing means at right angles to the remainder of the bracing means and securing the bent free ends to their respective panels.
The method preferably includes the step of conveying the body blank with the panels secured to it to box folding means to fold the body blank and the panels into a box.
BRIEF DESCRIPTION OF THE DRAWINGS
Figure 1 is a perspective view of a box;
Figure 2 is a plan view of a body blank for the box;
Figure 3 is a plan view of a panel for the box;
Figure 4 is a plan view of a bracing member or partition for the box;
Figure 5 is a diagrammatic plan view of a box erecting machine;
Figure 6 is a diagrammatic side view of the box erecting machine;
Figures 7 and 8 are cross-sectional side views of a body blank hopper and a body blank ejecting arrangement;
Figures 9 and 10 are cross-sectional side views of a panel hopper and a panel ejecting arrangement;
Figures 11 and 12 are cross-sectional side views of pillar forming dies and pressure plates;
Figure 13 is a plan view of a mandrel and preforming bars;
Figure 14 is a side view of a partition insertion station including inserting means;
Figure 15 is an end view of the partition insertion station;
Figure 16 is a plan view of a body blank with two panels secured thereto;
Figure 17 is a side view of the body blank and panels of figure 16;
Figure 18 is a plan view of a body blank showing the position of glue lines; and
Figure 19 is a perspective view of the box erecting machine excluding its partition inserting station.
DETAILED DESCRIPTION OF THE DRAWINGS
Referring firstly to figure 1, a box 10 made of corrugated cardboard has a base 12, two endwalls 14, two sidewalls 16 and an opening 18 through which articles can be placed in the box 10. Each sidewall 16 has an integrally formed reinforcing pillar 20 located intermediate the ends of the sidewalls 16. A partition 21 connects the reinforcing pillars 20 together.
The sidewalls may be longer or shorter than the endwalls in a rectangular box. In a square box the sidewalls and endwalls will be of equal length. However, it is to be appreciated, as will be described below, the reinforcing pillars 20 are formed in the two separate sidewalls, and not in the endwalls which are integrally formed with the base.
The partition 21 has integrally formed securing flaps 22 secured by an adhesive to the outer surfaces of the sidewalls 16. Each securing flap 22 spans its respective reinforcing pillar 20 and is secured to the outer surface of its sidewall 16 on either side of its reinforcing pillar 20. Each securing flap 22 is connected to the partition 21 by a crease line 25.
It will be appreciated that the partition 21 reinforces the sidewalls 16 from bulging outwardly under load and also supports the base of a box stacked on top of a lower box from sagging downwardly into the lower box. The securing
flaps 22 prevent the reinforcing pillars 20 from collapsing. However it will be appreciated that in certain applications the securing flaps 22 can be omitted.
Each endwall 14 has endwall flaps 24 adhered to the sidewalls 16 with adhesive. The base 12 has base flaps 26 adhered to the sidewalls 16 with an adhesive.
A ledge 28 extends inwardly from each endwall 14. Ledge flaps 30 extending from the endwall flaps 24 are secured with an adhesive to the upper surface of the ledges 28. The ledge flaps 30 serve to hold their ledges 28 in place and to reinforce the corners of the box. Ledge flap cut-outs 33 are provided in the base 12.1. The ledge flaps 30 of a lower box (not shown) locate within the ledge flap cut-outs of an upper box to locate boxes stacked one on top of the other.
Opposite ends of the sidewalls 16 are formed into corner reinforcing pillars 32 and securing flaps 34 extending from the corner reinforcing pillars 32 are secured to the endwalls 14 with an adhesive.
The box 10 is erected from a body blank 36, two separate sidewall panels 16.1 and a partition blank 21.1. The body blank 36 has a base panel 12.1, opposed endwall panels 14.1 , endwall flaps 24.1 with ledge flaps 30.1 , base flaps 26.1 , and ledge panels 28.1.
Referring now to figures 5 and 6, a box erecting machine 38 has a frame 40, a body blank hopper 42, two panel hoppers 44 located one on either side of a pillar forming and body blank and panel securing station 46 which includes pillar forming means and body blank and panel securing means. A box folding station 48 which includes folding means is located adjacent the station 46. A
brace or partition inserting station 54 which includes inserting means is located adjacent the box folding station 48.
Referring now to figures 5, 6, 7 and 8, the body blank hopper 42 is filled with body blanks 36 which are supported on four adjustable pins 52. Suction cups 54 on pneumatically operated piston rods 56 in use extend upwards, as shown by the dashed lines in figures 7 and 8, and make contact with the underside of a lowermost body blank 36. The suction cups 54 then retract and pull the body blank 36 past the adjustable pins 52 and deposit the body blank 36 between a pair of guides 58. Conveying means in the form of an endless chain 60 is mounted between the guides 58. The chain 60 runs over sprockets 62 and has kicker blocks 64 secured to it at spaced intervals.
In figure 7 a body blank 36 is shown in dashed lines abutting the kicker block 64. In figure 8 the kicker block 60 has moved forwards conveying the body blank 36 towards the station 46. A sensor 66 senses the leading edge of the body blank 36 and activates hot melt adhesive applicators 68 to apply lines of adhesive 69 to the endwall flaps 24.1 and to the base flaps 26.1 of the body blank 36 in a pattern shown in figure 18. The body blank 36 is moved forward by the chain 60 in a horizontal plane until a proximity sensor indicates that the midpoint of the body blank is in line with the apex 72 of a pillar forming means which is described in more detail below. The body blank 36 is now in position to be secured to the two panels 16.1 and is located in the pillar forming and body blank and panel securing station 46.
At the same time as a body blank 36 is withdrawn from the body blank hopper 42, a side panel 16.1 is ejected from each of the side panel hoppers 44 which are shown in more detail in figures 9 and 10.
Each panel 16.1 is pushed towards the longitudinal centre line 74 of the machine 38 against a stop 76 by a kick or an ejection plate 78 attached to a pneumatic cylinder 80. The side panel hoppers 44 are refilled with panels 16.1 via an opening 82. A pneumatic cylinder 84 has a piston rod 86 fixed to a pressure plate 88 to apply a preset gentle pressure to the panels 16.1 to ensure they remain flat and do not snag on an opening 90.
The ejection plate 78 has a step 92 which is clear of the panels 16.1 when the ejection plate 78 is in its retracted position (see figure 9). In its extended position (see figure 10), the step 92 forces the panels 16.1 upwardly away from the opening 90, thereby ensuring that only one panel 16.1 can be ejected at a time.
Before the panels 16.1 can be secured to the body blank 36, a pillar 20 is formed in each of the panels 16.1 by a pillar forming means 94 which is shown in more detail in figures 11 and 12. The pillar forming means 94 includes a female die 96 and a male die 98 with each die having an apex 72. Body blank and panel securing means in the form of the pressure plates 102 extend from either side of the female die 96 for applying pressure to the panels 16.1 to secure them to the body blank 36 as described in more detail below.
In figure 1 a panel 16.1 is showing lying on top of the male die 98 and between panel feed guides 104. Figure 12 shows the pillar 20 being formed in the panel 16.1. As the pillar 20 is formed, the pressure plates 102 press downwardly on the panels 16.1 to secure them to the base flaps 26.1 of the body blank 36. This occurs whilst the body blank 36 and the panels 16.1 lie in the same horizontal plane.
The female die 96 is reciprocated by a pneumatic cylinder 106. Pressure is maintained for a pre-determined time period on the panels 16.1 to allow
adequate bonding between the panels 16.1 and the base flaps 26.1. Figures 16 and 17 show the panels 16.1 with pillars 20 formed in them secured to the base flaps 26.1 of the body blank 36. The panels 16.1 and the body blank 36 lie in the same horizontal plane.
Referring again to figures 5 and 6, at the end of the pre-determined time period, a lifting mechanism 106 lifts the panels 16.1 clear of hopper ejection guides 108 and above a lead in to prefold guide rails 110 as the body blank 36 with the panels 16.1 secured thereto are moved forwardly by the kicker block 64 until the body blank 36 abuts an end stop 112. As the body blank 36 and the panels 16.1 are moved forwardly, glue applicators 114 apply beads of hot melt adhesive to the endwall panels 14.1 of the body blank 36. The panels 16.1 are folded at approximately 70° to the horizontal plane by the guide rails 110 thereby allowing the pillars 20 to pass underneath a mandrel 116 into the folding station 48.
Figure 13 is a plan view of the mandrel 116 with adjacent male preforming bars 118 in their retracted position. The male preforming bars 118 are moved horizontally towards the mandrel 116 by pneumatic cylinders 120. The panels 16.1 are clamped against the mandrel 116 by the male preforming bars 118. The mandrel 116 then moves downwardly to make contact with the body blank 36, and to push the body blank and the panels 16.1 through a series of folding ploughs into a squaring and clamping device 120 (see figure 6) which presses the endwall flaps 24.1 tight against the panels 16.1.
Ledge and flap folding arms 122 bend the ledge flaps 28.1 and the corner flaps 30.1 around the upper face of the mandrel 116. After a predetermined period of time the mandrel 116 collapses to allow it to be withdrawn past the ledges 28 to its upper position. The erected box 10 is then ejected out of the squaring and clamping device 120 by the next box. The erected box 0 is deposited on
an indexing conveyor 124 located below the squaring and clamping device
120.
The mandrel 116, preforming bars 118, folding ploughs, squaring and clamping device 120, and the ledge and flap folding arms 122 all form part of the folding means of the folding station 52.
Figure 14 is a side view of the partition inserting station 54 and figure 15 is an end view of this station 54. Referring to these two figures, the box 10 is positioned against a retractable stop 126. Inserting means in the form of an ejection plate 128 is pushed downwardly by a pneumatic cylinder 130 to push a partition 21.1 out of a partition hopper 132 past a guide 134. The ejection plate 128 then stops with the partition 21.1 located above the box 10. Bending means in the form of an arm 136 then moves forward in a horizontal plane and pushes against the securing flap 22 causing it to twist or bend at right angles against a guide 138. The ejection plate 128 then moves downwardly to insert the partition 21.1 into slots 40 in the pillars 20. During this time the box 10 is clamped square between two squaring plates 142 located between clamping plates 144 (see figure 5). The clamping plates 142 are operated by pneumatic cylinders 146.
The dashed lines in figure 15 show the partition 21.1 in the position in which the securing flaps 22 are bent or twisted at right angles to the remainder of the partition 21.1.
Once the partition 21 has been inserted into the box 10, the end stop 126 is retracted via the pneumatic cylinder 146. The indexing conveyor 124 then moves the completed box 10 out of the squaring device, consisting of the clamps 142 and the guide channel 144, and locates the next box in position within the squaring device for insertion of a partition.
The applicant has found that the invention permits the accurate and fast production of boxes. Each box is square because the body blank 36 and the panels 16.1 are accurately secured to one another after the pillars 20 are formed in the panels 16.1. If the pillars 20 were to be formed against the mandrel, there would be some relative movement between the panels 16.1 and the body blank 36.1 resulting in a lack of consistency and inaccuracy in the boxes.
It will be appreciated that many modifications or variations of the invention are possible without departing from the spirit or scope of the invention.