CA1123721A - Machine for making an improved variable flute container - Google Patents

Abstract

MACHINE FOR MAKING AN
IMPROVED VARIABLE FLUTE CONTAINER

Abstract An improved method of and machine for making a bulk container. The container has a main body which is strengthened as compared to at least the container top or bottom by at least one additional material layers, those material layers comprising in combination a single face liner and attached fluting medium. The variable layer construction is accomplished by machine combination of material layers of different cross-machine dimension. The method of this variable dimension multi-layer combination encompasses a single lamination step of the several material layers to provide a strengthened bulk container blank and therefrom the improved container of this invention.

Description

~ ~, f ~i This is a divisional of Canadian Patent Application Serial No. 296,667 filed February 10, 1978.
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Back~round of the Invention This invention relates to machines and methods for making bulk containers and the containers made therefrom. More particulariy, it is directed at a novel method and machine for making a bu k container and the container made therefrom char-acterized by a main body which is strengthened as compared to at least the container top or bottom by additional material layers.
Corrugated paperboard containers are often used to package ana ship a variety of bulk products. Usually these containers are constructed of fiberboard, paperboard, card-board and the li]ce. Often, they are waxed or treated with other materials to attain desired waterproofing and other characteristics. They may take many for~s and ~ay be used for many purpc~es--they may consist of folding boxes or car-tons, packing or shipping containers, collapsible and rigid casings and containers including transfer file cases, storase boxes, portable ward-robes, insulated containers, and other forms which are well known in the art. Examples of such con-tainers are disclosed in U.S. Patents 1,704,174, 2,276,363,

2,751,964, and 3,864,200.
Typically, these paperboard containers are rein-forced along the edges or fold-score lines to strengthen the composite construction and preclude corner and edge damage during handling. Such protection commonly takes the form of bonding tape-like reinforcing strips about the fold lines of the blank prior to container formation. Exemplifying this type of construction are U.S. Patents 1,425,914 and 1,600,396.
Another corner reinforcement technique, disclosed in U.S.
Patent 1,410,622, is characterized by longitudinal folds or ;

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23~Zl , ~ pleats in one of the webs of container blank. These special j pleats in the zones of the fold lines of the container blank f afford integral corner reinforcement and a neat appearance to I the formed box.
j 5 These construction methods, while of use in strengthen-ing the edges of the formed container, do not provide that high compressive strength needed in the packaging of heavy articles which are incapable of withstanding compressive force. Such , packages tend to bulge when stacked one upon the other. ~ore-,. 10 over, they are likely to be damaged by side panel shocks and ¦ jars.
! One method to increase the lateral strength of paper-board containers comprises stiffening that corrugated paper-board employed to form the container. Such technique, dis-closed in U.S. Patent 3,586,564, makes use of plastic which r, is capable of withstanding compressive force without bendins.
¦ The plastic is formed into narrow strips and dropped into the corrugated flutes at desired intervals. The resultant blanX
is materially stiffened in a direction parallel to the flutes.
It permits a container construction which displays desired high compressive strength and lateral protection. However, this construction requires specialized apparatus for feeding and correctly positioning the narrow plastic strips on the flutes of the corrugated medium. Moreover, the use of plastic 1 25 increases the cost of the formerly paper container.
¦ Another method which enhances the compressive strength of a paperboard container and better protects its contents against lateral jars and shocks is disclosed in U.S. Patent 1,550,646. There, a lining, prefera~ly of corrugated paper or cardboard, is inserted into the container before use. This .

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lining is characterizccl by double-ply top and bottom eflges and a sin~le-ply ccntral portion. This center portion comprises a corrugated paper or cardboard core sandwiched between two lincr sheets. On insertion, this construction provides a container ! S having an air space between its outer side walls and the central ! portion of the liner. The formed inner air space cushions the packaged material from any lateral shocks and jars. The liner itself strensthens the compressive resistance of the box.
Although this method avoids those disadvantages in-herent in the use of plastic stiffening material, it reauires off-machine liner formation and resultant insertion in a formed j box. Additionally, should it be desired to la~inate the lirer to the box, a further lamination step would be necessarv. As regards the container itself, that air spacé separation between , i5 the container outer walls and the central portion of the liner ¦ reduces substantially the compressive and bulging resistance o-the combination.
Other lining techniques are known in the prior art.
These include the lamination of a single face liner-fluting-single face liner combination to the main body of the container.
Such techniques require a second lamination step. Importantlv, they also require an inner single face liner surface to cor-rectly position the glue lines prior to lamination.

Summarv of the Invention Accordingly it is an object of this invention to provide a machine for making a bulk container, which container is characterized by a main body which is strengthencd as comparcd to at least the container top or bottom by at least onc additional material layer, this laycr comprising in combination, a single face liner and attached fluting mcdium.

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It is still another object of this invention to pro-vide a machine for forming the novel variable dimension multi-layer container on line such that only a single laminatlon step is required.
The invention in one aspect provides in a machine for forming a reinforced web of paperboard material comprising, in combination: at least one of a first source of single face liner;
at least one of a first source of corrugated medium; and at least one of a first single facing means to combine single face liner from said first source thereof with corrugated medium from said first source thereof to form at least one of a first material layer; the improvement comprising: at least one of a second source of single face liner, the liner fxom said second source having a cross machine dimension less than that of the liner from each of said first sources, said dimension difference between said liner from said first source and said liner from said second source being equal to that portion of said liner from said first source forming at least one of the top portion and bottom portion of a container formed from said reinforced corrugated web; at least one of a second source of corrugated medium, said medium having the same cross-machine dimension as said liner from said second source thereof; at least one of a second single facing means to combine said single face liner from said second source thereof with said corrugated medium from said source thereof to form at least a second material layer; a gluing means to apply adhesive to each of said first and said second material layers; a source of double face liner; and a double facing means to form a combination consisting of said first material layers and said second material layers, said combination having no single face liner in contact with another single face liner and no fluting medium in contact with another fluting medlum, and said combination being capped at the sole remaining unfaced fluting medium with said double faced liner.

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~ he above-noted parent application describes and claims a container which is preferably made by the machine of the present invention which container is characterized by a main body having at least one additional material layer, comprising in combination a single face liner and attached fluting medium, as compared to at least the container top or bottom. The additional layers are laminated to the container blank simultaneous to its formation.
The machine provides a means of combining several material layers, at least one of which has a smaller cross-machine dimension than the others. By employing these webs of varied cross-machine dimension, this machine permits construction of a blank having a main body, which is strengthened as compared to at least the blank top or bottom by one or more additional material layers, said material layers comprising in combination a single face liner and attached fluting medium. The container may therefore be constructed in a single combination and lamination step. Therefore, the machine avoids the disadvantages inherent in the prior art plasticizing of blanks or lining of formed containers. The container formed` from the novel blank displays good compressive strength and resists - 4a -~.23~

bulging when packaged heav~ but compressible articles are stacked one upon the other. Moreover~ the container displa~s good lateral strength so as to protect the packaged goods from lateral shocks and jars during handling.

! s Descri~tion of the Drawings Fig. 1 is a perspective view of a contalner of this invention formed of corrugated paperboard material, parts being broken away for purposes of clarity.
Fig. 2 is a section view along lines 2-2 of ~ig. 1 of a container of this invention.
' Fig. 3 is a similar view to Fig. 2 of another embodi-ment of this invention.
I Fig. 4 diagrammatically illustrates the machine and ¦ method according to this in~-ention for forming a container like that depicted in Fig. 1.

Description of the Preferred Embodirents Referxing to Fig. 1 of the drawings, there is shown therein a container 10 of this invention. For the purposes of clarity two top flaps are shown as representative of the top portion of the container. It is however to be understood that the top and bottom portions of the containers of this invention may comprise any of those combinations famili.ar to the art. Moreover, while the depicted construction utilizes conventional corrugated paperboard, it is to be understood that other well-known packaging materials can liXewise be ; employed. Those skilled in the art will recognize the selec-tion of specific materials from such corrugated packaging materials as fiberboard, cardboard, paperboard, and the like so as to attain desired packaging characteristics specific to the articlcs packaged. While container 10 is displayed as a ~L ~ r 3~J~ 1 box in Fig. 1, other well-known packaging forms are equally amenable to that improvement which characterizes this inven-tion, the particular shape of container being most controlled by its expected use.
Container 10 is formed from a blank by well-known container methods. As depicted it comprises top portion 11, bottom portion 12 (shown closed in Figs. 1 and 2), and a four sided main body 13. The top portion for purposes of illustration is shown as two flaps lla and llb. Each top flap is integral with opposing sides of the main body. Thus, as shown in Fig. 1, top flap lla is integral with main body side 13a and top flap llb is integral with main body side 13c, sides 13a and 13c being opposite sides of the container.
As best illustrated in Fig. 2, top portion 11 pref-erably comprises two material layers 14 and 15 capped with a double faced liner 16. For the purposes of this description a material layer is taken to mean the combination of a single face liner and attached fluting medium. Each material layer 14 and 15 comprises a single face liner 14a and 15a and attached fluting 14b and 15b, the unattached side of fluting 14b being joined to the unfluted side of liner 15a. This remaining uncovered fluting l5b is capped by double faced liner 16. The method of producing such fluting liner com-binations are well-known in the art. While in the embodi-ments depicted in Fig. 2, bottom portion 12 is of similar layerconstruction to top portion 11, it is to be understood that this parallelism is not necessary. Rather, the top portion may be formed of a different number of material layers than the bottom, i.e. top portion 11 may comprise two material layers and bottom portion 12 may comprise three material layers. For the purposes of this description, the construction of the top ~ 2~

or bottom portion having the least number of material layers is termed the basic container blank.
That portion of the container between the top portion and the bottom portion and integral therewith is termed the main body. In accordance with this invention the main body, of the same initial uncapped material layer construction as the basic container blank, is strengthened as compared to at least the top or bottom portion by at least one additional material layer. In Fig. 2, this reinforcement is illustrated by additional material layer 17, comprising single face liner 17a and attached fluting 17b. Such additional material layers are situated by the improved method and machine of this inven-tion preferably adjacent a material layer of the basic container blank between such material layer and the double faced liner capping. Hence, the container of this invention is not merely a conventional container with an insert comprised of single face liner-fluting-single face liner added to the main body atop the double face liner. Here, the reinforcing is only a single face liner and attached fluting. And, it is inserted preferably between fluting 15b and double faced liner 16.
It is to be understood that similar reinforcement of the top portion or the bottom portion of the basic blank but not both is also contemplated by this invention. Such an embodiment is depicted in Fig. 3.
While only a single material layer of main body reinforcing is illustrated in Figs. 1 and 2 multiple rein-forcement is also possible. Such an embodiment is shown in Fig. 3. There, top portion 18 comprises a single material layer 18. This layer comprising single face liner 18a and fluting 18b is capped at 18b by double faced liner 18c. This basic blank is reinforced in both the main body 19 and bottom poxtion 20. The main body is reinforced by three additional z~

material layers 21, 22, and 32 and the bottom portion is rein-forced by a single corrugated material layer 21. Main body reinforcing material layers 21, 22, and 32 comprise fluting 21a, 22a, and 32a and single face liners 21b, 22b, and 32b attached thereto. They are attached to material layer 18 of the basic blank between this layer and double faced liner 18c. Thus, the reinforced main body of the container comprises four material layers of single face liner-fluting combinations 18a-b, 21a-b, 22a-b, and 32a-b capped by double faced liner 18c. The fluting material of each such layer is sandwiched between single facers, the final exposed fluting layer 32b being capped by the double faced liner 18c. Bottom portion reinforcing material layer 21 comprises fluting 21a and single face liner 21b. It is attached to the uncapped basic blank, material layer 18, liner 21b on fluting 18b. The combination is then capped with double face liner 18c.
In those preferred embodiments depicted in Figs. 2 and 3, the reinforcement is laminated between the material layer of the basic blank and the double faced liner. However, the reinforcement could as well be positioned on the outer con-tainer surface of the basic blank or less preferably inter-mediate to one or more material layers of the basic blank. In this intermediate positioning embodiment all of the smaller dimensioned material layers must be positioned in so-called dimensional congruence with each other. That is each must bear the same relative positioning to the larger material layers.
Referring to Fig. 4, a diagram of a preferred machine and method for forming the preferred containers of this inven-tion is shown. The apparatus differs from conventional corru-gated paperboard container machines in that a material layer,a single face liner-fluting combination, of smaller cross-machine dimension is combined with the more normal material layer components of a corrugated container prior to their gluing and lamination together. As illustrated, this machine and method afford construction of that container, whose edge is depicted in Fig. 2 by a combination of several multi-dimensional layers. A first material layer is formed atsingle facer 23 by the conventional combination of single face liner 14a and single face fluting medium 14b. Such fluting medium is formed from paper stock by methods well-known in the corrugation art. A second material layer, having the same cross-machine dimension as the first such layer is formed by a similar combination of single face liner 15a and 1uting medium 15b at single facer 24. A third material layer, having a smaller cross-machine dimension than the first two such layers is formed at single facer 25 from single face liner 17a and fluting medium 17b. The difference between the cross-machine width of this material layer and the others is equal to that portion of the first layers which will correspond to at least the top or bottom portions of that container formed from the blank. More preferably, the dimension of this smaller material layer corresponds to the size of the main body.
Glue is applied to each of the material layers in a conventional manner at gluing stations 26a, 26b, and 26c, respectively. Then, the three material layers are combined in a sandwich-like fashion fluting 14b on liner 15a and fluting 15b on liner 17a. This sandwich construction insures that no single face liner is in surface contact with another single face liner and no fluting medium is in surface contact with another fluting medium. Simultaneously, fluting 17b, the remaining uncovered fluting, is capped by double face liner 16, supplied from web 31. The composite blank is then ~i.s~:;i72~

laminated together in double facer 27, the initial adhesive bonds being cured with heat in a conventional manner.
The combination blank may be trimmed to appropriate cross-machine dimension and cut to length using a conventional cutting means. Conventional uni-dimen~ion blanks re~uire only passage through triplex slitter/scorer 28 to attain that cor-rect cross-machine dimension and crease embossment for final container formation. However, th~ multi-dimensional blanks of the instant invention require passage through auxiliary slit-ters to trim the smaller dimension material layers in thecross-machine dimension, one slitter being required for each such smaller dimensioned layer. Preferably, such auxiliary slitters are located near the standard triplex slitter/scorer so as to better utilize the existing trim removal system.
However, it should be understood that those auxiliary slitting means for trimming the smaller dimen ioned material layers to be combined intermediate to the larger dimensioned layers may be positioned anywhere between the single facer forming the smaller layer and the double facing means. Conversely, those auxiliary slitting means for trimming the smaller dimensioned layers not to be combined intermediate the larger layers may be located anywhere between that single facer and the final cutting means.
In the preferred embodiment illustrated in Fig. 4 the composite blank passes through auxiliary slitter 29 to trim smaller dimension layer 17a-17b in the cross~machine dimension and then through standard triplex slitter/scorer 30 to trim the other single-face webs in the cross-machine dimension and emboss the creases that form the bends in the final corrugated container. Finally, the trimmed blank is cut to length by the rotary cut-off knife 30.

While we have hereinbefore presented a number of embodiments of our invention, it is apparent that our basic construction can be altered to provide other embodiments which utilize our invention. Thus, it will be appreciated that the scope of our invention is to be defined by the claims appended hereto rather than the specific embodiments which have been presented hereinbefore by way of example.

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Claims (2)

The embodiments of the invention in which an exclusive property or privilege is claimed are defined as follows:

1. In a machine for forming a reinforced web of paperboard material comprising, in combination:
at least one of a first source of single face liner;
at least one of a first source of corrugated medium; and at least one of a first single facing means to combine single face liner from said first source thereof with corrugated medium from said first source thereof to form at least one of a first material layer; the improvement comprising:
at least one of a second source of single face liner, the liner from said second source having a cross machine dimension less than that of the liner from each of said first sources, said dimension difference between said liner from said first source and said liner from said second source being equal to that portion of said liner from said first source forming at least one of the top portion and bottom portion of a container formed from said reinforced corrugated web;
at least one of a second source of corrugated medium, said medium having the same cross-machine dimension as said liner from said second source thereof;
at least one of a second single facing means to combine said single face liner from said second source thereof with said corrugated medium from said source thereof to form at least a second material layer;
a gluing means to apply adhesive to each of said first and said second material layers;
a source of double face liner; and a double facing means to form a combination consisting of said first material layers and said second material layers, said combination having no single face liner in contact with another single face liner and no fluting medium in contact with another fluting medium, and said combination being capped at the remaining unfaced fluting medium with said double faced liner, said remaining unfaced fluting medium consisting of in combination fluting medium from said second material layers and fluting medium from said first material layers.

2. The machine of claim 1 including a cutting means located after said doublt facing means for dividing said web in a cross-machine direction into sheets.