US2246614A - Method and apparatus for closing and sealing cartons - Google Patents

Description

June 24, 1941.

R. M. BOTLEY METHOD AND APPARATUS FOR CLOSING AND SEALING CARTONS Filed April 4, 1940 '4 Sheets-:Sheet '1 INVENTOR Rump M. BoTAEY sy- A TTORNEY June 24, 1941. M, BQTLVEY 2,246,614

METHOD AND APPARATUS FOR CLOSING AND SEALING CARTONS Filed April 4, 1940. 4 Sheets-Sheet 2 C I 204 I 206 INVENTOR Temmm; M BoTLEy BY ATTORNEY June 24,1941.

R. M. BOTLEY IIETHOD AND APPARATUS FOR CLO$ING AND SEALING CARTONS 4 Sheets-Sheet 3 Filed April 4,

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INVENTQR M- Honey BY V * imiaf June 24, 1941. R M B T EY 2,245,614

METHOD AND APPARATUS FOR CLOSING AND SEALING CARTONS Filed April 4, 1940 4 sheets-sneak 4 INVENTOR Glenn M. Born-y P, x f

ORNEY Patented June 24, 1941 METHOD AND APPARATUS FOR CLO SING AND SEALING CARTON S Richard M. Botley, Honolulu, Territory of Hawaii assignor to Hawaiian P ited, Honolulu, tion of Hawaii ineapple Company, Lim- Territory or Hawaii, a'eorpora- Application Aim 4, 1940, Serial No. 327,837

13 Claims. 1 (01. 93-6) The present invention relates to packing cases, more particularly cardboard or fiberboard cartons, and to methods and apparatus for making cartons and for closing and sealing the same.

The conventional fiberboard carton employed for packing canned goods and the like is rectangular in shape having side and end hinged flaps forming the top and bottom. The combined width of the side flaps is substantially equal to the width of the carton but to make the combined length of the end flaps equal to the length of the carton would involve heavy waste of material in cutting the carton blank, so that, for reasons of economy, these flaps are made shorter than the length of the carton and leave a considerable gap between their ends when closed. The resultant uneven inner surface at the top and bottom of the sealed carton is productive of considerable damage to the contents during shipment, since it leaves the central vertical layers of articles in the carton relatively loose and permits them to jounce' up and down, causing breakage,

denting, label scuffing andv the like.

To remedy this diificulty, it has heretofore been proposed to provide the carton blank, prior to folding, with pads secured to a surface at the portions intended to constitute the inner surface of the side flaps, in position to lie within the gaps carton is packed and during the sealing thereof, whereby the increase in transportation and storage space consequent whenthe padsare secured to the fiat carton blank is avoided, and savings in time and cost of the pad-attaching operation are effected. A furtherobject of the invention is to provide apparatus for the economic practice of the said method, said apparatus, preferably, including parts present in carton sealing machines of a well-known type and mechanism of relatively inexpensive construction adapted to operate in conjunction with said parts to apply the filler pads to the side flaps of a packed carton while it is being operated upon by the sealing machine, without increasing the time nor, to any significant extent, the expense now required for the sealing of cases.

A still further object of the invention is to provide anovel form of filler pad or strip adapted for use in filling the gap between the end flaps of a carton, said novel filler pad being less expensive to make than pads now in usefor the purpose, but equally satisfactory in performance.

between the end flaps when the blank is folded to form the carton. Such a carton blank construction is shown and described in United States Patent No. 2,001,850, dated May 21, 1935, and a machine for stapling the. pads onto the carton blanks is illustrated and described in United States Patent No. 2,070,704, dated February 16, 1937, While cartons formed from such blanks are generally satisfactory as regards a smooth inner surface at the top and bottom for level riding of the contents, the practice of adding filler pads to the carton blanks has proved costly for several reasons. In the first place, the thickness of the blanks is doubled where the filler pads are attached. so that the space required for shipment and storage of the blanks is likewise doubled.

, Moreover, addition of the filler pads to the carton blanks requires either a time-consuming hand operation or complicated, expensive machinery.

It is an object of the present invention to provide an improved, less costly method for making a carton having its side flaps provided with filler pads lying within the gap between the end flaps when the carton is sealed. said method contemplating the securing of the pads to the side flaps after the carton has been formed from the conventional fiat-surfaced blank, preferably after the Other objects and advantages of the invention will be apparent from the ensuing more particular description and from the accompanying drawings wherein:

Fig. l is a top plan view of part of a carton sealing machine embodying filler pad applying mechanism of the invention;

Fig. 2 is a side elevation of one of the devices for applying filler pads .to the top side flaps of packed cartons moving through the machine, said device being illustrated at the moment of application of a pad to one of the top side flaps of a passing carton;

Fig. 3 is a front elevation of the devices for applying the tiller pads to the top side flaps of the cartons, and of a carton in actuating engagement therewith, with some adjacent parts of the sealing machine shown in elevation, some in section;

Fig. 4 is a side elevation of part of one of the devices for applying filler pads to the bottom side flaps of packed cartons moving through the machine, said view being takenon a vertical section on the line -A-A of Fig. 1 looking in the direction of the arrows, with parts of the machine above and below the pad applying device broken away.

Fig. 5 is a plan view of parts of the pad applying mechanism shown in Fig. 4 and of additional parts thereof, illustrating particularly the mechanism for effecting transfer of a pad to position for application to a bottom side flap of a carton approaching through the machine;

Fig. 6 is a side elevation of part of the mechanism for applying a filler pad to a bottom side flap, and of part of a passing carton;

Fig. 7 is a perspective view of a packed carton having the side fiaps provided with filler pads according to the invention, the side fiaps at the top of the carton being opened to show the pads;

Fig. 8 is a plan view of a novel filler pad of the invention with the flap-engaging surface uppermost;

Fig. 9 is a partial longitudinal section through the top of a sealed carton showing the filler pad of Fig. 8 secured to the top side flaps in position between the top end flaps.

As in Patents NO. 2,001,850 and No. 2,070,704 above referred to, the present invention contemplates the production of a-packed carton having at top and bottom unmeeting end flaps over which are secured meeting side fiaps, the inner surfaces of each of the top and bottom side flaps having secured thereto a filler pad of such size and shape and so positioned that when the side flaps are closed over the end fiaps each filler pad lies within the gap between the corresponding end fiaps substantially filling said gap for its full depth and approximately half its length. Such a carton is illustrated in Fig. '7 of the appended drawings, the end flaps being designated by the letter E, the side fiaps by the letter S and the filler pads by the letter F. The aforesaid patents, however, contemplate the addition of the pads to the flat blank before it is folded to form the carton, as a step in the manufacture of the carton blank. v

I have discovered that very considerable savings are effected and that the production of such cartons is materially simplified if the filler pads are applied to the side flaps after the carton is formed from the fiat blank, particularly if the application of the pads to the flaps is effected as a part of the process of sealing the carton. In the sealing of packed cartons, whether by machine or by hand, the customary steps are to open up the side flaps, apply adhesive to their inner faces, close them over the end flaps and apply sufiicient pressure to effect bonding to the end fiaps by the adhesive. The preferred practice of the method of the present invention is a modification of this process by the inclusion of an additional step, the attachment of a suitably shaped filler pad to the inner face of each of the side flaps while they are held open, in registry with the gap between the end flaps so as to lie therein when the flaps are closed and pressed.

When, as is usually the case, adhesive is applied over the entire inner faces of the side fiaps, performance of this additional step, after the adhesive has been applied, actually requires merely loose placement of the filler pads on the inner faces of the side flaps in proper registry with the gap between the end flaps, a loose bond between adhesive on the side flaps and the filler pad being suificient to retain the pad in position while the side flaps are folded back over the end fiaps, so that the pad enters the gap between the end flaps and is there held against displacement by the end flaps while sealing pressure is applied to the side flaps. If the process is performed by hand, proper placement of the filler pads is a relatively simple matter, since the gap between the end flaps is exposed to view and it is merely necessary to line up the pads with the exposed gap as they are applied. If the sealing process is performed by machine, as is usually the case, means, such as is shown in the drawings and hereinafter described, may be provided for adapting the machine to automatically perform the added step of applying the filler pads to the side flaps in conjunction with the other steps without slowing the noraml operation of the machine.

It will thus be seen that with the practice of the process of this invention attachment of the filler pads to the carton adds little to the expense of the packed carton beyond the cost of the pads themselves, since most of the steps of the process are in any event performed in the sealing of the carton and the added step of applying the filler pad at the proper stage of the sealing process is one that may be easily performed by hand or.

that is capable of automatic performance by a sealing machine with suitable added mechanism while it is performing its regular sealing operations.

On the other hand, attachment of filler pads to the flat carton blank, as in the above men tioned patents, is comparatively difficult and costly. The pads must be firmly fixed in proper position because otherwise, projecting from the surface of the blank, they are liable to be torn loose during subsequent handling of the blank.

For this reason, in the aforementioned patents. the pads are stapled to the blank, a painstaking operation if done by hand and requiring complex mechanism if done by machine. The attachment medium, whether adhesive or staples, must be supplied, not being already present as in the process of the invention, and also, if adhesive is used, sufficient pressure must be applied to secure a firm bond, again a step rendered unnecessary by the process of the present invention.

In addition to the above mentioned economies, considerable savings in shipment and storage space and cost are effected by supplying the blanks and pads separately to the packer for the practice of the method of the present invention.

An important advantage of the process of the invention is the readability with which standard types of carton sealing machines may be adapted to include performance of the process as part of their automatic sealing operations. In Fig. 1 of the appended drawings there is shown such a machine equipped with mechanism for practicing the method of the invention, said mechanism being shown in more detail in Figs. 2-6.

Referring first to Fig. 1, the carton sealing machine there illustrated is of a common type substantially, similar to that shown and described in United States Patent No. 2,095,258, dated October 12, 1937, to which reference may be had to supplement the ensuing description. In the machine shown, an elongated main frame structure I0 supports a central slide I2 along which the packed cartons C are continuously conveyed from left to right in Fig. 1, between laterally adjustable top guide rails I4 and bottom guide rails I6 by means of pusher bars I8 secured at their ends to endless sprocket chains 20 extending along opposite sides of the slide over driven sprocket wheels 22 at the rear end of the slide and idler sprocket wheels (not shown) at the forward end of the slide. The cartons are fed onto the forward end of the slide I2 between successive pusher bars I8 resting on their bottom inner or end flaps with the bottom outer or side flaps extending downwardly at the sides of the slide and with the top side flaps loosely closed over the top inner flaps, suitable means for this As a carton is advanced along the slide I2, 8.

pair of front plows 24 enter under the top side flaps of the carton and open them upwardly andv outwardly onto horizontal slides 26 extending along opposite sides of the slide I2. Simultaneously, a pair of lower front plows (not shown), similar to the plows 24 and having their forward ends disposed beneath the slide l2 engage the inner faces of the downwardly extending bottom side flaps and raise them to substantially horizontal position on supporting slides (not shown) below the slides 26. Further advancement of the carton passes the extended top side flaps beneath a pair of gluing rollers 28 fed by glue tanks 30, said rollers applying'a coating of glue to the upper surface constituting the inner face of the flaps. Similarly and at the same time, the extended bottom side flaps pass over a pair of gluing rollers (not shown) disposed below the rollers 28 which apply a coating of glue to the lower surface constituting the inner face of the bottom side flaps.

As the carton approaches the rear end of the slide l2, the side flaps at top and bottom of the carton encounter upper and lower pairs of rear plows, of which only the upper pair 32 is shown, the upper plows folding the top side flaps back over the top of the carton and the lower plows turning the bottom side flaps up beneath the slide. On further advancement, the carton passes off the rear of the slide l2 onto a coriveyor (not shown) on which it rests on its bottom side flaps, said conveyor, under the weight of the packed carton or further pressure applied thereto, acting to bond the adhesive coated surface of the bottom side flaps firmly to the bottom end flaps. A presser foot 34, suspended over the rear end of the slide l2, and flanged rollers 36 on the rear ends of the guide rails l4, press the top side flaps down onto the top end flaps sufficiently to effect preliminary sealing of the tops of the cartons which may then be subjected to further pressure to complete the sealing.

In accordance with the present invention, to the conventional carton sealing machine so far described there is added means designated generally by the reference numeral 40 for automatically placing a filler pad upon the inner face of each top side flap, and means designated generally by the reference numeral I for automatically placing a filler pad upon the inner face of each bottom side flap, in registry with the gap between the corresponding pair of end flaps, after the adhesive coating has been applied to the side flaps and before they are folded back over the end flaps.

The means 40 for applying filler pads to the topside flaps, which is shown in Figs 1-3 of the drawings, comprises a pair of pad-holding magazines 42 attached to a transverse bar 44 of the sealing machine frame just to the rear of the top gluing rollers 28, having their lower ends disposed close above the path of the extended top side flaps of a carton advancing from the gluing rolls, and mechanism actuated by the advancing carton for ejecting a filler pad from each magazine fiat on the adhesive coated face of the top side flap advancing beneath it, in registry with the gap between the top.end fiaps. These magazines and ejectors are substantially similar to the magazine and ejector shown in U. S. patent of Harry S. Fox and Kenneth W. Emerson, No. 2,203,900, issued June 11, 1940, for the purpose of inserting a filler strip in the gap between the top end flaps of a carton passing through a sealing machine. Since the two magazines 42 and their ejectors are identical, a

- description of one will suffice.

As best shown in Fig. 2, the magazine 42 is a rectangular box-like structure, open at the top, adapted to hold a stack of horizontally disposed iiller pads F having a length approximately equal to the width of the carton side flap and a width approximately equal to the width of the gap between the carton end flaps. The width of the magazine is adjustable for different width pads by means of a movable ertically disposed plate 46 suspended on bolts 48 extending slidably through the rear wall of the magazine and having wing nuts 50 threaded on their outer ends. The magazine is attached to the bar 44 by means of a bracket 52.

In the rear wall of the magazine at the bottom thereof there is provided a slot 54 (see Fig. 3) affording edgewise passage therethrough for the lowermost filler pad of the magazine, which is in registry with said slot. The front wall of the magazine is also provided with a slot, in registry with the slot 54, through which a pusher plate 56, slightly thinner than a filler pad, is advanced to push the lowermost pad through the slot 54 out 'of the magazine. The forward end of plate 56 is attached at each side to shafts 58 slidably mounted in horizontal position through portions of the front and rear walls of the magazine projecting beyond the end walls. The innermost of these shafts, which overlies the path of travel of the body of a carton advancing on the slide 12, is provided with a rearward extension in the form of a bracket 60, between the side arms of which, near their rearward and forward ends respectively, are pivoted a depend- I ing trigger member 62 and a latch bar 64, the bar having at its forward end an upstanding finger 66 and at its rearward end an inverted U-shaped hood member 68 adapted to fit over the sides of the trigger member 62 to guide the end of the latch bar 64 into engagement with a tooth 10 on the upper end of the trigger member 62.

The rearward end of each of the shafts 5B is provided with a collar 12 to which is attached one end of a coil spring 14 connected at the other end to a collar 16 on a rod 18 mounted through the front and rear walls of the magazine above the adjacent shaft 58.- The rearward end of the innermost of these rods 18 extends considerably beyond the rear wall of the magazine and has threaded thereon a nut 80. The innermost shafts 58 of each of the two magazines 42 may be connected together by a transverse strut bar 82.

As a carton advances under the magazines 42 its front end engages the triggers 62 which are held rigidly in vertical position by engagement of the ends of the latch bars 64 with the teeth 10 of the triggers, the triggers 62 being so disposed to the rear of the magazines 42 that engagement of the carton therewith takes place at the moment the longitudinal center line of the gap between the end flaps of the carton comes into registry with the corresponding center line of the stack of pads in the magazine. As the carton advances further the shafts 58 and pusher plates 56 advance therewith forcing the lowermost filler pad of each magazine 42 through the slots 54 so that it falls fiat on the adhesive coated face of the side flap passing therebeneath, in side registry with the gap besealing machine.

tween the end flaps, as shown in Fig. 2. As the filler pads leave the magazines, the fingers 66.0f the latch bars 64 strike the nuts 80 on the innermost rods 18 causing the bars to pivot, lifting their ends from engagement with the teeth 10 of the triggers 62, leaving the triggers free to pivot and thereby releasing them from positive engagement with the carton. Springs 14 then return the ejector mechanism to retracted position.

The adhesive coating on the side flaps adheres sufficiently to the filler pads dropped thereon from the magazine to hold them in their position of registry with the gap between the end flaps until the side flaps are folded over by the rear plows. As the side flaps are folded over, therefore, the pads enter the gap between the end flaps where they are held in place by the end flaps and the contents of the carton immediately below the gap during the application of sealing pressure to the top flaps, which also acts to bond the pads firmly to the side flaps.

The means I for applying filler pads to the bottom side fiaps, shown in Fig. 1 and more particularly in Figs. 4-6 of the drawings, comprises in general a pair of pad-holding magazines I02 mounted on opposite sides of the frame II) of the sealing machine immediately to the rear of the gluing rollers for the bottom side flaps, having their lower ends disposed to the side of and slightly below the path of the extended bottom side flaps of a carton advancing from the gluing rollers, mechanism initiated by the advancing carton for transferring a filler pad from each magazine to predetermined position beneath the path of the adjacent advancing bottom side flap, and means operated by the advancing carton for raising each filler pad into flat engagement with the adhesive coated face of the bottom side flap advancing over it. These magazines and transfer mechanisms are similar to the magazine and transfer mechanism shown in U. S. patent of Francis N. Todd and Kenneth W. Emerson, No. 2,203,901, issued June 11, 1940, for the purpose of inserting a filler strip in the gap between the bottom end flaps of a carton passing through a Since the two trains of mechanism for applying a filler pad to each of the bottom side flaps are identical, a description of one will suffice.

As best shown in Figs. 1 and 4, each magazine I02 comprises a vertically disposed end plate I04 mounted on a base plate or horizontal slide I06 secured to the frame I0, 'and a pair of side plates I08 connected to the slide I06 and end plate I04 in any convenient manner. The bottom filler pads F are stacked in horizontal position between the side plates I08 with one end abutting against the end plate I04 and with the lowermost pad of the stack resting on the slide I06. 1

Slide I06 has its inner end disposed below the path of one of the extended bottom side flaps of a carton passing through the sealing machine and is provided centrally with a slot IIO extending from its outer end under the magazine to adjaceint its inner end. Through said slot IIU extends the upper stretch of a sprocket chain II2 operated by a driven sprocket H4 at the outer end of the slot and running over an idler sprocket H6 at the inner end of the slot, said sprocket II6 being rotatable on a stub shaft II8 fixed to a bracket I20 secured to the frame I0. Chain H2 is provided with a projecting pusher pin I22 which passes under the bottom filler pad in the magazine when the sprocket H4 is in normal lowered position but which will engage the outer end of the lowermost filler pad in the magazine to push it endwise through a suitable slot (not shown) in the end plate I04 to the opposite end of the slide I06 when the sprocket I I4 is raised by mechanism now to be described.

As shown in Fig. 5, sprocket H4 is fixed to an end of a stub shaft I24, said shaft being rotatably continuously driven by means of bevel gear I42 fixed thereto meshing with bevel gear I44 on a convenient driven shaft I46 of the machine.

Bar I28, which supports shaft I24, is provided at its inner end with a collar I48 by which it is pivotally mounted on stub shaft I I8, and interme diate its ends rests upon a cam bar I50 having a raised end or lobe I52, said bar I50 in turn resting on a bracket I54 secured to the frame I0, and being slidable on said bracket between guide pins I56. Adjacent its-opposite end, bar I50 rests slidably between guide pins I58 on bracket I60 secured to frame I0, and at said end has pin and slot connection with a rod I62. Rod I62 is fixed to a stub shaft I64, the lower end of which is rotatably mounted on the frame I0. Shaft I64 is turned in the clockwise direction in Fig. 5 by means of an arm I66 projecting over the slide I2 to engage the front end of a carton advancing along the slide toward the magazines I02, as shown in Fig. 5. As shaft I64 is turned by the carton advancing against. arm I66, rod I62 is turned, drawing bar I50 to the left as shown in Fig. 5, lifting bar I28 by means of lobe I52, which in turn raises shaft I24 and sprocket II4 causing pin I22 to engage the outer end of the lowermost filler pad in the magazine and push it onto the inner end of slide I06 where it leaves the pad, passing downward out of engagement with the pad around the sprocket 6. When the carton passes by the end of arm I66, the shaft I64 and its associated parts are returned to initial position by means of coil spring I68 (see Fig. 4) surrounding shaft I64 and connected thereto and to frame I0, lowering sprocket I I4 before pin I22 can engage another filler pad in the magazine.

By means of the mechanism so far described, a filler pad is automatically positioned on the inner end of each slide I06 under the path of each bottom side flap of an approaching carton. Means, now to be described, are also provided for automatically raising said pads into engagement with the adhesive coated under surface of the bottom side flaps in side alignment with the gap between the bottom end flaps of said advancing carton.

Referring to Figs. 5 and 6, it will be seen that the inner end of each slide I06, disposed beneath the path of one of the extended side flaps of the carton, is provided with a raised rim I10 which acts to stop and center each pad pushed thereon by pin I22, and with two longitudinal slots I12. Rotatably mounted in bearings I14 on a plate I16 disposed below said end of slide I06, are a pair of rollers I18, said rollers being normally disposed below the slots I12, but adapted to be raised through said slots when plate I16 is lifted toward slide I06. The inner end of the plate is provided with a lever arm I80, extending rearwardly of the machine parallel to the slide I2 and having at its rearward end a raised portion or cam I82. Lever I80 is mounted on a horizontal pivot I84 so that normally plate I16 is in its lowered position with the rollers I'I8 disposed below the upper surface of slide I06 and cam I82 is in raised position above the plane of the surface of slide I2.

As a carton is advanced along slide I2, the front end of the carton, at each of its sides, which overhang the sides of the slide as indicated in Figs. 4 and 5, strikes the cams I82 pivoting lever arms I80 about pivots I84 to lift plates I16 and correspondingly raise rollers I18 through slots I72 in slides I06. As rollers I18 are lifted through slots I'I2 they engage the bottom surface of each filler pad resting on the inner end of the slide, lifting it above the raised rim I of the slide and pressing its upper face into engagement with the adhesive coated under surface of the bottom side flap passing thereover, at the moment the gap between the bottom end flap reaches side registry with filler pad. As the pad is pressed into engagement with the adhesive coated under surface of the continuously travel- Lng side flap, it moves rearwardly with the carton, the rollers I'I8 being freely rotatable to afford virtually no frictional resistance to such movement of the pad and consequently avoiding relative sliding movement between the pad and the flap which would remove the pad from its desired location on the flap. To assure the proper horizontal positioning of the side flap as it passes over the end of the slide I06, a guide roller I86 is provided in advance of the slide I06 in position to engage the outer edge of the side flap and press its upper surface against a horizontally disposed guide plate I88.

While the carton travels to the rear end of the machine and its side flaps are refolded over the corresponding end flaps, the bottom filler pads are held by the adhesive in the position in which they were applied by the rollers I18, so that on refolding of the side flaps the pads are brought or the other of the above mentioned types of carton cardboard. t

I have found that an equally satisfactory but less expensive filler pad may be made of a twoply composition cardboard. As shown in Figs.

8 and 9 of the accompanying drawings, my novel @filler pad comprises a layer 204 of smooth relatively thin cardboard and, secured to one face of said layer 204, a second layer 206 of corrugated cardboard, the combined thickness of the layer 204 and the depth of the corrugations of the layer 206 being substantially equal to the thickness of the carton cardboard. As will be seen by reference to Fig. 9, which is a longitudinal section through the top of a sealed carton having one of my novel flller pads fastened therein, the corrugated face of the pad is secured to the surface of the side flap so that the inner face of the pad presents a smooth surface level with the inner surface of the adjacent end flaps. The tips of the corrugations of the layer 206 furnish suflicient surface to provide a firm bond between the pad and a layer of adhesive on the surface of the side flap, although the pad may be stapled to the side flap if desired.

My improved filler pad has all the requisite strength and yet is less expensive to make than into the gap between the end flaps, and are there bonded permanently to the side flaps by the application of sealing pressure to the carton. As the rear end of a carton passes over the cam I82, the lever arm I80 rocks back to its initial position, and the cycle of operations previously described is repeated as the next carton advances through the machine.

With the economies effected by the methods and apparatus of the present invention, the cost of applying filler pads to the gaps between the end flaps adds practically nothing to the cost of the packed carton beyond the actual cost of the material in the pads themselves. In order to elfect further savings, I have devised a novel form of filler pad which is less expensive than pads heretofore in use.

In order to withstand the shocks incident to shipping and handling, cartons of the type here involved are usually made of heavy, thick cardboard which may be an integral thick cardboard sheet or a laminated structure such as that shown in Fig. 9 which comprises face layers 200 of smooth cardboard and an intermediate layer 202 of corrugated cardboard secured to the inner opposed surfaces of the face layers 200. In order to fill the gap between the end flaps in such cartons to provide a level inner surface, it is obviously necessary to employ a filler pad having the same thickness as the end flaps, and it has been the practice heretofore to employ a pad made of one prior pads since a greater part of its thickness is made up of corrugations. The savings effected, though slight per carton, amount to a very substantial figure for packers requiring large quantities of cartons.

It will be apparent that by describing and illustrating herein preferred procedures and embodiments I do not intend to limit the invention to all details thereof and that various changes may be made therein without departing from the spirit and scope of the invention.

I claim:

1. In a method of sealing a carton having inner cover flaps spaced apart at their ends to form a gap and an overlapping outer cover flap, the steps which comprise opening said outer flap to expose its inner surface, attaching to said inner surface of said outer flap a filler pad in position to lie in said gap on closing said outer flap and closing and sealing said outer flap over said inner flaps.

2. In a method of sealing a carton having a pair of inner cover flaps spaced apart at their ends to form a gap and an overlapping outer cover flap, the steps which comprise opening said outer flap to expose its inner surface, applying a coating of adhesive to said inner surface of said outer flap, adhering to said adhesive coating a filler pad in position to lie in said gap on closing said outer flap, closing said outer flap over said inner flaps, and bonding said adhesive coating of said outer flap to the outer surface of said inner flaps.

3. In a method of sealing a carton having a pair of inner cover flaps spaced apart at their ends to form a gap and an overlapping outer cover flap, the steps which comprise opening said outer flap to expose its inner surface, applying a coating of adhesive to said inner surface of said outer flap, adhering to said adhesive coating a filler pad in position to lie in said gap on closing said outer flap, closing said outer flap over said inner flaps, and pressing said adhesive coated surface of said outer flap against said inner flaps and said filler pad.

4. In a method of sealing cartons by securing an outer flap over a pair of unmeeting inner flaps, the steps which comprise continuously advancing a carton and while advancing the carton opening said outer flap to expose the inner surface thereof, attaching to said inner surface of said outer flap a filler pad in position to lie in th: gap between said unmeeting flaps on closing said outer flap thereover, and closing and sealing said outer flap over said inner flaps.

5. In a method of sealing cartons by securing an outer flap over a pair of unmeeting inner flaps, the steps which comprise continuously advancing a carton and while advancing the carton opening said outer flap to expose the inner surface thereof,

applying a coating of adhesive to said inner surface of said outer flap, adhering to said adhesive coating a filler pad in position to lie in the gap between said unmeeting flaps on closing said outer flap thereover, closing said outer flap over said inner flaps and bonding said adhesive coating of said outer flap to the outer surface of said inner flap.

6. In a method of sealing cartons having a pair of inner cover flaps spaced apart at their ends to form a gap and an overlapping outer cover flap, the steps which comprise opening said outer flap to substantially horizontal position with the inner surface thereof downwardly exposed, applying a coating of adhesive to said inner surface of said outer flap and lifting a filler pad into engagement with said adhesive coating to adhere thereto in position to lie in said gap on closing said'outer flap.

7. In a method of sealing cartons by securing outer flaps over unmeeting inner flaps to form opposite walls of the carton, the steps which comprise advancing the carton resting on a pair of said inner flaps, with said outer flaps opened to expose the inner surface thereof, applying a coating of adhesive to the inner surfacaof each said outer flap, adhering to said adhesive coating on each said outer flap a filler pad in position to lie in the gap between the corresponding unmeeting inner flaps on closing the outer flaps, closing the outer flaps over the inner flaps and bonding the adhesive coatings of the outer flaps to the outer surface of the corresponding inner flaps.

8. In apparatus for sealing cartons by securing outer flaps over unmeeting inner flaps, means for advancing a carton with a said outer flap open to expose the inner surface thereof, means for applying a coating of adhesive to said exposed inner surface of said outer flap, means for adhering a filler pad to said adhesive coating in position to lie in the gap between the corresponding unmeeting inner flaps on closing said outer flap, and means for closing said outer flap over said inner flaps and bonding said adhesive coating of said outer flap to the outer surface of said inner flaps.

9. In apparatus for sealing cartons by securing pairs of outer flaps over pairs of unmeeting inner flaps to form opposite walls of the carton, means for advancing a carton with said outer flaps open to expose the inner surface thereof, means for applying a coating of adhesive to the exposed inner surface of each said outer flap, means for adhering a filler pad to the adhesive coating on each said outer flap in position to lie in the gap between the correspondingpair of unmeeting flaps on closing the outer flaps, and means for closing said outer flaps over said inner flaps and bonding said adhesive coatings of said outer flaps to the outer surface of the corresponding pair of said inner flaps.

10. In apparatus for sealing cartons by securing outer flaps over unmeeting inner flaps, means for opening a said outer flap at the top of a said carton to substantially horizontal position, means for applying a coating of adhesive to the inner surface of said outer flap, and means for dropping a filler pad onto the adhesive coated surface of said outer flap in position to lie in the gap between the corresponding unmeeting inner flaps on closing said outer flap over said inner flaps.

11. In apparatus for sealing cartons by securing outer flaps over unmeeting inner flaps, means for opening a said outer flap at the top of a said carton to substantially horizontal position, means for applying a coating of adhesive to the inner surface of said outer flap, means for dropping a filler pad onto the adhesive coated surface of said outer flap in position to lie in the gap between the corresponding unmeeting inner flaps on closing said outer flap, and means for closing said outer flap over said inner flaps and bonding the adhesive coating of said outer flap to the outer surface of said inner flaps.

12. In apparatus for sealing cartons by securing outer flaps over unmeeting inner flaps, means for opening a said outer flap at the bottom of a said carton to substantially horizontal position, means for applying a, coating of adhesive to the inner surface of said outer flap and means for pressing a filler pad onto the adhesive coated surface of said outer flap in position to lie in the gap between the corresponding unmeeting inner flaps on closing said outer flap over said inner flaps.

13. In apparatus for sealing cartons by securing outer flaps over unmeeting inner flaps, means for opening a said outer flap at the bottom of a said carton to substantially horizontal position, means for applying a coating of adhesive to the inner surface of said outer flap, means for pressing a filler pad onto the adhesive coated surface of said outer flap in position to lie in the gap between the corresponding unmeeting inner flaps on closing said outer flap, and means for closing said outer flap over said inner flaps and bonding the adhesive coating of said outer flap to the outer surface of said inner fiaps.

RICHARD M. BOTLEY.

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