GB2096093A

GB2096093A - Box flap sealing apparatus

Info

Publication number: GB2096093A
Application number: GB8208169A
Authority: GB
Original assignee: Gerber Products Co
Current assignee: Gerber Products Co
Priority date: 1981-03-27
Filing date: 1982-03-19
Publication date: 1982-10-13
Also published as: DE3210875A1; IT8248087A0; FR2502583A1; GR81338B; IT1189241B

Abstract

Apparatus for folding and sealing the flaps of a box as it passes continuously along a conveyor comprises a folder e.g. a paddle wheel (8) which is supported above the conveyor, for folding forwardly front- and rear-end flaps (F, R) of a box passing thereunder, a guide, e.g. successive guide rails (34, 48), for engaging the forwardly folded end-flaps (F, R) as they are released by the folder to keep them folded forward, a front end-flap folder member (52) which engages the front end flap after the latter has left the aforesaid guide and urges said flap rearward over the box, means (40-44) for applying adhesive to at least one to side flap, and side flap guide rails (54, 56) which sequentially engage the side flaps and fold them over the two end- flaps (F, R) before the end-flaps are released and apply pressure to seal the box. In a preferred arrangement, a forwardmost end-flap guide rail (48) is arranged to be axially displaceable under the control of a photo sensor to alternately increase and decrease the spacing of the guide rail from the front flap folding member (52). <IMAGE>

Description

SPECIFICATION Box flap sealing apparatus This invention relates to a method for sealing boxes and to box sealing apparatus, particulary one in which no timing or box positioning mechanisms are required for folding the flaps of a box as it moves along a constantly moves belt.

To seal boxes, particularly boxes which have been filled and need only to have their flaps on the top of the box folded over and glued shut, timing or positioning mechanisms have typically been required. These mechanisms often require that the box be stopped temporarily while the folding of the flaps is accomplished. However, any interruption of the orderly flow of goods along the product line generally slows the process down and therefore increases the cost of the product.

The timing or positioning mechanisms required have often been complex and costly.

The present invention solves some of the problems associated with prior art box sealing apparatus in that it requires no timing, positioning or position sensing mechanisms to properly fold and seal the end flaps and side flaps of a box as it passes along a conveyor.

Thus according to the invention there is provided a box flap sealing apparatus comprising conveyer means for the continuous movement of boxes therealong in a forward direction, means for arranging said boxes so as to have front and rear end flaps disposed transverse to the forward direction of movement of said boxes and side flaps disposed parallel to the forward direction of movement of said boxes; means for folding said end flaps forward as each said box moves forward along said conveyor means; an end flap positioning means disposed above the boxes passing along said conveyor means and positioned to keep each said end flap, previously folded forward by said end flaps forward folding means, folded forward until said respective end flaps reach a first position along said conveyor means at which position they are respectively released; means for applying adhesive to at least one of said flaps; a front end flap folding means disposed above the boxes passing along said conveyor means and forward of said first position for folding said front flap back over said box after said front end flap has been released by said end flap rail means; and a side flap guide rail means located generally forward of said first position for folding said side flaps over said box and onto said end flaps whereupon said adhesive secures said side flaps to said end flaps. The preferred embodiment of the apparatus includes a horizontal conveyor belt along which previously filled, open boxes pass. A pair of vertically disposed gripping belts, parallel to the horizontal belt, move at the same speed as the horizontal belt so that the boxes are securely held in place during the flap folding operations.

A rotating paddle wheel is supported above the the horizontal belt and rotates so that the ends of the paddle wheel, as they pass closest to the belts, are moving in the same direction as the belts. The speed of the ends of the blades exceed that of the boxes. The rotating paddle wheel blades engage and fold forward, that is, in the direction of travel of the boxes, the front and rear end flaps of the box passing thereunder.

A first end flap guide rail mounted directly above the horizontal belt engages the for wardly folded end flaps as they are released by the blades of the paddle wheel. In the preferred embodiment a gluing station next applies an adhesive to the inner surfaces of the side flaps of the box.

After passing the gluing station a second end flap guide rail keeps the end flaps in a forward folded position until the box reaches the terminal end of such second guide rail.

When the front end flap reaches such terminal end it naturally springs back to a more verti cal, upwardly extending attitude. A short dis tance forward of such terminal end, a front end flap folder member engages the recently released front end flap and urges it rearward over the box.

The second end flap guide rail may be made movable parallel to the belts to allow the position of its terminal end to be adjusted according to whether a front or a rear end flap is passing such terminal end. This aids the proper functioning of the front end flap folder member.

In the general area of the terminal end of the second end flap guide rail and the front end flap folder member, a right side flap guide rail engages the right side flap of the box and begins to fold it over the top of the two inwardly folded end flaps. By the time the rear end flap has cleared the terminal end of the second end flap guide rail, the right side flap has been folded over the top of the box sufficiently to maintain the end flaps in their inwardly folded positions. A left side flap guide rail operates to fold the left side flap over the top of the box as well. The left and right side flap guide rails apply sufficient pressure to the top of the box for a sufficient length of time to insure that the flaps are adhered properly. The sealed box then exits from between the gripping belts and passes along the product line.

A primary advantage of the present inven tion arises because the flap folding steps are accomplished automatically as the boxes con tinue to pass along the conveyor without the requirement for employment of any timing, position sensing or positioning apparatus.

Therefore the complexity of the apparatus is reduced by allowing the boxes to be sealed while continuously moving along the product line. This is accomplished by provision of means such as the paddle wheel above the horizontal belt and the various guide rails forward of the paddle wheel. Provision of means such as the gripping belts ensures that the boxes remain upright and continue to move along the conveyor at the proper speed.

Hereinafter the invention is described by way of example and with reference to the accompanying drawings, wherein: Figure 1 is a top or plan view of the apparatus according to the present invention.

Figure 2 is an enlarged side view representation of the major operating elements of the apparatus of Fig. 1.

Figure 3 is á cross-sectional view taken along line 3-3 of Fig. 1.

Figure 4 illustrates a box having an open toF with the end and side flaps extending generally vertically upwardly.

Figure 5 is an enlarged top view of a portion of the apparatus of Fig. 1 showing an alternative guide rail.

Figures 6A and 6B are side view representations of the major operating elements associated with the alternative guide rail of Fig. 5 with the piston rod extended and retracted, respectively.

Turning now to Figs. 1-4, broadly the apparatus comprises a horizontal conveyer 2, a pair of gripping belts 4, 6, a paddle wheel 8 having a number of blades 10 mounted over horizontal conveyer 2, a gluing station 1 2 mounted forward of paddle wheel 8, and a number of flap guide rails for folding the various flaps over the top of a box B during the sealing operation. In this application forward wil mean in the direction of an arrow 14 and rearward will mean in the direction opposite arrow 14.

Boxes B, having been previously filled with a product, are fed onto a horizontal belt 1 6 of horizontal conveyor 2. As the box moves forward along belt 16, it passes between gripping belts 4, 6. Belts 4, 6 pass around idler rollers 1 8 at one end and drive rollers 20 at the other. Horizontal belt 1 6 and gripping belts 4, 6 are driven at equal speeds through conventional drive trains by a motor 22. Horizontal belt 1 6 rides along a platen 24 which supports belt 1 6 along its upper reach. Gripping belts 4, 6 are adjustably spaced apart over horizontal belt 1 6 via adjusters 26 mounted to a frame 28.The space between belts 4 and 6 can therefore be adjusted so that the boxes passing therebetween are gripped with a desired amount of force.

It has been found desirable to use gripping belts 4, 6 so that boxes B do not tip over or slip when passing beneath paddle wheel 8 and when engaged by the various guide rails described below. However, other means for insuring that the boxes do not slip along belt 1 6 by temporarily securing the boxes to hori zonal belt 1 6 can be used. For example, belt 1 6 could be provided with a number of vertically extending holes along the center line so that a vacuum can be applied through the holes to the bottom of the boxes to keep the boxes in place. Another method may be to provide the upper surface 30 of belt 1 6 with spaced apart, upwardly projecting portions to contact one end of the box.In certain cases, depending upon the weight of the material in the box, the size of the box and the material from which the box is made, it may be unnecessary to use any sort of apparatus to keep the box from slipping while the top is held and glued in place. For example, large boxes of laundry detergent may be heavy enough and stable enough to be so manipulated.

The blades of the paddle wheel have centrally located slots 32. This allows the paddle wheel to pass around a first end flap guide rail 34 which extends to a point generally centrally beneath paddle wheel 8. As seen best in Fig. 2, the paddle wheel rotates in the direction of arrow 36 so that the distal ends 38 of blades 10 engage and fold forward front flap F and then rear flap R of box B. The paddle wheel, driven by a motor 37, rotates fast enough so that distal ends 38 move at a speed greater than the speed of horizontal belt 1 6. As the front and rear box flaps pass under paddle wheel 8, they disengage from blades 10 but are restrained from assuming their normal generally vertical attitude by guide rail 34.

Guide rail 34 is attached centrally to and beneath a side flap spreader 39 which itself is a part of gluing station 1 2. Gluing station 1 2 is mounted to frame 28 in a conventional manner and includes a pair of adhesive dispensers 40. Dispensers 40 are each connected to a source of adhesive, not shown, via lines 42. Preparatory to applying the adhesive, side flaps S, S' are spread outwardly by edges 46 and 47 of spreader 39 until such flaps are generally horizontal. Each flap S, S' then passes between the horizontal portion 47 of spreader 39 and a support 51. Supports 51 are mounted directly beneath horizontal portion 47 and dispensers 40 to support the side flaps while adhesive is applied onto the inside surfaces of side flaps S, S' at glue dispensing surfaces 44 of dispensers 40. The end flaps, while passing beneath gluing station 12, are kept in their forwardly directed attitude by engagement with the underside of spreader 39.

A side flap guide 49 is provided immediately forward of gluing station 14 and above conveyor 2. As side flaps S, S' leave gluing station 12, their natural tendency to spring upwardly is arrested by guide 49. This keeps the newly applied glue from being flung off of the flaps, which may occur if the flaps were allowed to spring upwardly unrestrained. The forward portion of guide 49 is inwardly tapered to permit the side flaps to gradually reassume their natural upwardly extending attitude, thus eliminating adhesive spray.

A second end flap guide rail 48 is mounted to gluing station 1 2 and extends in the direction of arrow 14 parallel to horizontal belt 1 6.

When front flap F of box B passes the terminal end 50 of guide rail 48 it naturally springs to a more vertical attitude. A short distance forward, that is in the direction of arrow 14, of terminal end 50 a front end flap folder member 52 is mounted to the frame. Member 52 engages front flap F and folds it in a direction opposite arrow 14 down over box B.

As this is occurring, right side side flap S' engages a right side flap guide rail 54 which begins to draw side flap S' back over the top of box B. By the time rear end flap R has cleared terminal end 50, right side flap S' has been folded down over the top of box B sufficiently to hold the front and rear end flaps over box B.

At a suitable location forward of terminal end 50 a left side flap guide rail catches left side flap S and folds it over the top onto the previously folded flaps. The forward ends 58, 60 of guide rails 54, 56 are typically positioned to apply sufficient pressure to allow the adhesives to set and seal the package. The sealed box B then exits from between drive rollers 1 8 to proceed along the product line.

The operation of the apparatus of the present invention proceeds generally as follows.

Boxes B are fed onto upper surface 30 of belt 1 6. It should be noted that the boxes will not be adjacent to one another but will have an appropiate space between then so that the operations on one box will not interfere with those of an adjacent box. The boxes pass between idler rollers 1 8 and are secured between gripping belts 4, 6. As the boxes pass beneath paddle wheel 8, front and rear end flaps F and R are folded forward and kept in the forward folded position by first end flap guide rail 34. The boxes then pass gluing station 1 2 at the which side flaps S, S' are spread outwardly to a horizontal attitude to have adhesive applied to their inside surfaces.

The gluing station may incorporate sensors, such as light sensitive elements, for the application of adhesive to the flaps. However, other adhesive dispensing systems can also be used. After the box has passed gluing station 12, the front and rear end flaps are retained in their forward folded positions by guide rail 48. When the front flap F passes terminal end 50 of guide rail 48, it springs upwardly to a more vertical attitude so that as the front flap passes beneath folder member 52, the front flap is folded rearward and over box B. In the general area of terminal end 50 and folder member 52, the right side flap engages guide rail 54 and begins to be folded down over the top of box B and flaps F and R. By the time end flap R clears terminal end 50, side flap S' keeps rear flap R and front flap F from springing back upwardly.Guide rail 56 then begins to fold left side flap S over onto the box.

Forward ends 58, 60 of guide rails 54, 56 apply sufficient pressure to the folded faps to allow the adhesive to seal the box.

Referring now also to Figs. 5, 6A and 6B, an alternative arrangement of guide rail 48 is shown. It has been found that it may be desirable to change the distance between terminal end 50 and member 52 depending upon whether front flap F or rear flap R is being engaged by member 52. To accomplish this a movable guide rail 48' is used in place of guide rail 48. Guide rail 48' is supported by an actuator assembly 70 mounted above platen 24 by a support bracket 72 attached, such as by bolts 74, to frame 28.

Actuator assembly 70 includes a pneumatic cylinder 76 from which a piston rod 78 extends. Forward and rearward movement of rod 78 is controlled through pneumatic lines 80. A mounting block 82 is fixed to the outer end of rod 78 and supports a depending link 84 which in turn supports rail 48' at its lower end.

A photosenser 86 is supported from bracket 72 to be near the sides of boxes B as they pass beneath cylinder 76. Photosensor 86 controls the operation of pneumatic cylinder 76 according to the presence or absence of a box B adjacent photosensor 86. As indicated in Fig. 6A, photosenser 86, sensing box B, causes piston rod 78 to extend thus moving terminal end 50' in a rearward direction, that is, opposite arrow 14. This increases the distance between end 50' and member 52 to allow front flap F to spring up in the direction of arrow 88 after it passes end 50'. Member 52 subsequently engages front flap F and directs it back over box B.

After box B passes photosensor 86 piston rod 78 is retracted moving end 50' forward towards member 52 as shown in Fig. 6B.

This insures that rear flap R is held down sufficiently long to allow member 52 to engage rear flap R and keep it folded down over box B.

Modification and variation can be made to the disclosed embodiments without departing from the subject of the invention as defined in the following claims. For example, paddle wheel 8 could have a greater or lesser nuber of blades which may have different shapes.

The blades could be solid with no slot therein but located to pass to one side of guide rail 34. Instead of paddle wheel 8, a brush-like member could be used as well. Also, a jet of compressed air could be used to accomplish the same result. If desired, one of the side flaps could be preliminarily folded vertically downwardly along the side of box . This would allow a horizontally disposed paddle wheel to be used in lieu of the disclosed, vertically disposed paddle wheel 8. After the front and rear flaps were folded forward, the downwardly folded side flap could be allowed to assume its original generally upwardly extending attitude and then be manipulated as in the present embodiment. Further, gluing station 1 2 could be placed before paddle wheel 8 and could be arranged to apply glue to at least the one side flap.

Claims

1. A box flap sealing apparatus comprising conveyer means for the continuous movement of boxes therealong in a forward direction, means for arranging said boxes so as to have front and rear end flaps disposed trasverse to the forward direction of movement of said boxes and side flaps disposed parallel to the forwad direction of movement of said boxes; means for folding said end flaps forward as each said box moves forward along said conveyor means; an end flap positioning means disposed above the boxes passing along said conveyor means and positioned to keep each said end flap, previously folded forward by said end flaps forward folding means, folded forwad until said respective end flaps reach a first position along said conveyor means at which position they are respectively released; means for appying adhesive to at least one of said flaps; a front end flap folding means disposed above the boxes passing along said conveyor means and forward of said first position for folding said front flap back over said box after said end flap has been released by said end flap rail means; and a side flap guide rail means located generally forwad of said first position for folding said side flaps over said box and onto said end flaps whereupon said adhesive secures said side flaps to said end flaps.

2. Apparatus according to Claim wherein said end flap rail means includes means for varying said first position according to the presence of a box at a box sensing position along said conveyer means.

3. Apparatus according to Claim 1 or 2 wherein said end flap rail means includes a rail having a terminal end, the location of said terminal end defining said first position.

4. Apparatus according to any preceding claim wherein said conveyor means includes means for pisitively advancing said boxes along said conveyor means.

5. Apparatus according to Claim 4 wherein said conveyor means includes a pair of vertically disposed side belts located parallel to and above a horizontally disposed bottom belt, said belts driven forwad at the same surface speeds, whereby said boxes travelling along said bottom belt are captured between said side belts for said positive displacement along said conveyor means.

6. Apparatus according to any preceding claim wherein said end flaps folding means includes at least one rotating member adapted for turning about an axis, transverse to said forward direction, the distal end of said member having a speed greater than the speed at which said boxes move along said conveyor means so that as said boxes pass said rotating member said distal end engages said end flaps and folds said end flaps forward.

7. Apparatus according to any preceding claim wherein said adhesive applying means is located between said end flaps forward folding means and said first point.

8. A box flap sealing apparatus comprising conveyor means for the continuous movement of boxes therealong in a forward direction including means for arrangement of said boxes so as to have front and rear flaps disposed transverse to the forward direction of movement of said boxes and side flaps disposed parallel to the forward direction of movement of said boxes, said conveyor means including means for releasably securing said boxes to said conveyor means to positively advance said boxes along said conveyor means; means for folding said end flaps forward as each said box moves forward along said conveyor means, said means mounted above said conveyor means and having at least one movable member adapted to engage said front and rear end flaps, said member moving at a speed greater than the speed of said boxes so that said front and rear end flaps are folded forward by said end flaps folding means; an end flap positioning means disposed above the boxes passing along said conveyor means and position to keep each said end flap, previously folded forward by said end flaps forward folding means, folded forward until said respective end flaps reach a first position along said conveyor means; means for applying adhesive to at least one of said flaps; a front end flap folding means disposed above the boxes passing along said conveyor means and forward of said first position for folding said front flap back over said box after said front end flap has been released by said end flap rail means; said end flap rail means including means for varying said first position according to the presence of a box at a box sensing position along said conveyor means; and a side flap guide rail means located generally forward of said first position for folding said flaps over said box and onto said end flaps whereupon said adhesive secures said side flaps to said end flaps.

9. A method for sealing the flaps on boxes having open tops as said boxes continuously pass along a conveyor means, said method comprising continuously transporting a series of said open top boxes along said conveyor means in a forward direction, said boxes having upwardly extending front, rear and side flaps; applying an adhesive to at least one of said flaps; providing means above said conveyor means for folding said front and rear flaps forward as said boxes pass said forward folding means; passing said boxes under an end flap rail supported above said coveyor means to maintain said front and rear flaps folded forward until said front and rear flaps pass the forward end of said end flap rail; engaging said front flap after said front flap has passed said forward end of said end flap rail; folding said engaged front flap in a rearward direction opposite said forward direction; engaging said side flaps; and folding said side flaps inwardly over said box and said forwardly folded rear flap and said rearwardly folded front flap so that said adhesive bonds said flaps to seal said box.

1 0. A method according to Claim 9 and further comprising the step of positioning said forward end of said end flap rail at a rearward position before said front flap passes said forward end and at forward position before said rear flap passes said forward end.

11. A method according to Claim 9 or Claim 10 wherein said front and rear flaps folding means includes a paddle mounted for continuous movement above said conveyor means for contact with said upwardly extending front and rear flaps, said paddle being rotated at a speed greater than the speed of said boxes and in the same direction as said boxes so that engagement of said paddle with said front and rear flaps cause said front and rear flaps to be folded forward.

1 2. A method according to any of Claims 9 to 11 wherein said boxes are positively held in position on the conveyor as they are advanced along it.

1 3. Apparatus for sealing the flaps of boxes substantially as described herein with reference to Figs. 1 to 4 or modified as shown in Figs. 5, 6A or 6B.