US2294846A - Valvular bag - Google Patents

Description

Sept. 1, 1942. A. c. HAuNGs VALVULAR BAG Filed Nov. 10, 1939 2 Sheets-Sheet l Sept. 1, 1942. A. c. HAuNGs 2,294,846

VALVULAR BAG Filed Nov. 10, 1939 2 Sheets-Sheet 2 NVM/*V314 4% Patented Sept. l, 1942 vALvULAR BAG Albert C. Haungs, Peoria, Ill., assignor to Bemis Bi'o. Bag Company, St. Louis, Mo., a corporation of Missouri Application November 10, 1939, Serial No. 303,743

1 Glaim. (Cl. 229- -62.5)

This invention relates to bags, and with regard to certain more specific features, to valvular bags.

The invention is an improvement on United States Patents l,444,118, 2,102,685 and 2,040,335.

Among the several objects of the invention may be noted the provision of an improvement in the valve of a valvular bag whereby the valve may function more eifectively as a sealing means against leakage after the bag has been filled with material through the valve; and thegprovision of such an improvement which may be quickly and easily accomplished during bag manufacture. Other objects will be in part obvious and in part pointed out hereinafter.

The invention accordingly comprises the elements and combinations of elements, features of construction, and arrangements of parts which will be exemplified in the structures hereinafter described, and the scope of the application of which will be indicated in the following claim.

In the accompanying drawings in which is illustrated one of various possible embodiments of the invention:

Fig. 1 is a plan view showing gusseted tubing of a length for forming a bag;

Fig. 2 shows the tubing of Fig. 1 cut to provide extending material for valve, the tube also being shown closed at its bottom;

Fig. 3 is a fragmentary enlarged view of the' upper left-hand portion of Fig. 2 and showing an applied notch;

Fig. 4 is a ho-rizontal section taken on line 4-4 of Fig. 3;

Fig. 5 is a left-side elevation of Fig. 3, but showing certain gussets expanded;

Fig. 6 is an enlarged fragmentary view of the upper left-hand corner of a bag with the valve portions thereof turned in;

Fig. 7 is a view similar to Fig. 6 showing a closure tape applied;

Fig. 8 is a perspective view showing the parts of Fig. 7 in a filled condition;

Fig. 9 is a horizontal section taken on line 9-9 of Fig. 8 looking upwardly into the bag and showing the valve of the invention in sift-proof position;

Fig. 10 is a Vertical section taken on line IO-IO of Fig. 7;

Fig. 11 is a view similar to Fig. 10 showing a partially filled condition of a bag; land,

Fig. 12 is a view similar to Fig. 11 showing a finally filled condition of a bag.

sponding parts throughout the several views of the drawings.

Referring now more particularly to Fig. 1, there is shown at numeral l a multi-ply paper tube which has front and back walls and which is inwardly gussetcd as'shown at numerals 3 and 5. Each gusset is formed by three creases, as indicated in Fig. 4. The upper end of the tube l is rectangularly cut as indicated, at 1 in Fig. 2 to provide an extension 9, said extension 9 including the upper end of the gusset 3.

Fig. 2 also shows the application to the lower end of the tube I of a closure strip which is sewed'into position as indicated, or which may be adhered by other means. It is to be understood that the strip may be applied at any time during the process of making the structure herein discl-c-sed and its showing in Fig. 2 is simply, for convenience in description.

Fig. 4 shows how the extension 9 consists (of a part of the gusset 3 wherein two edges |3 are included. These edges are notched as shown at 15 in Figs. 3 and 5. The notches may be effected simply'by cutting laterally with one stroke across both edges |3 whereby finite triangular areas of material are removed, the notches |5 being V- shaped as indicated in Figs. 5 and 6; or they may be other than V-shaped, and may be formed otherwise. For example, the notches may be plain slits having parallel edges formed by slitter knives which cut all plies in one operation, or which cut each ply separately. Therefore, the showing in the drawings of a V-shaped notch is not to be taken as limiting of notch shapes, although, as pointed out above, the V-shaped modification has certain advantages.

Similar reference characters indicate corre- Each extension is provided with certain crease or score lines which may at this time be considered. These are first, diagonal lines l'l on opposite sides of the bag. These lines I'l (on opposite sides of the bag) are directed at 45 from the corner of the cut-out portion 'l (see Fig. 3). In Fig. 5 are also shown in the gusset 3, the application of 45 diagonal crease lines |9 and a lateral crease line 2|. Between the lines |9, in a Vertical position, is also part of the inner edge of gusset 3.

In the drawings, exterior views of crease lines are shown with dashes. The crease lines are made in a manner so that the paper under suitable manipulation will break into the form shown in Fig. 6 wherein the gusset 3 is broken as indicated so as to direct the extension 9 inwardly. Portions of the gusset 3 then lie at right angles as shown at 3a and 3b. In this condition the bag is flat. This causes the crease lines |9 of Fig. 5 to become located in common, at'an angle of 45, as shown in Fig. 6. This 'places the edges |3 as indlcated with the notched end portions IS thereof against the inner sides of the bag.

The upper end of the bag is then closed by means of a suitable tape or like closure, as indicated in Fig. 7. In Fig. 7 the closure 23 is shown as a covering tape which is sewed in position. It is to be understood that this tape also may be adhered or otherwise held.

The above construction leaves an empty, flat bag which is closed on both ends, having a valve therein of lozenge-shaped cross section, which, being openable, may be entered along the dotted arrow shown in Fig. 7. The available opening is shown in Fig. 11. Entry may be made by means of a fllling tube or the like for filling the bag with comminuted or like material. As the bag fills, it takes on a shape such as shown in Figs. 8, 9 and 12, wherein the lozenge-shaped valve, which has theretofore been relatively flat in a Vertical plane (see Figs. 7 and 10), becomes flat in a relatively horizontal plane. That is, the notches |5 instead of being fiatwise adjacent one another as shown in Figs. 7 and 10, separate to the position shown in Figs. 9 and 12, while hinging occurs along lines |31, |3 and 3b, thus' causing the lower portions L of the valve to move as toggles against the upper portions U.

Thus the notches |5 lie adjacent the sides of the bag and relieve for flexing the inwardly directed edges E of the portions L and U (see Fig. 9). ,These edges thus assume positions flat against one another and against the top of the bag. Thus the invention functions as a fiexibleedged closing valve against escape of material packed in the bag (see Fig. 12).

It will be clear that all showing of multi-ply materials is diagrammatic, and that any number of plies may be used. Even a single-play bag could have thepresent invention applied thereto. The present showing is of a four-ply bag.

Advantages of the above-discussed construction over valve constructions heretofore used are these:

Unlike the construction in Patent 1,444,118, the fiexible lips E are not broken along their edges throughout their widths. Such breaking down by a multiplicity of slits or notches causes a plurality of incipient openings in the direct path of leakage through which sifting may take place. The present invention maintains a continuous, but flexible, sealing line across the valve, the flexibility being provided at the two sidewise notches |5. These notches also being in line With the creased edges l3 provide maximum lateral flexibility. The central crease 3b (extension of the gusset 3) is all that is necessary for vertical flexibility. Another point in this connection isrthat as shown in Fig. 12 the lower portions L of the lozenge, being unbroken by any intermediate notches, definitely toggle' upwardly with free motion at the then lateral notches I 5.

The construction of Patent 2.040.335, in which flexibility is attempted by means of a central slot; also has the effect of providing an opening for leakage at a position which is not as advantageous as applicant's position.

The present device is also an improvement over the construction shown in Patent 2.102.685, in that the notching for flexing is disposed laterally and near the side of the bag.

The flexibility of the valve is gained herein by slitting at the gusset line of the bag. This defines a maximum valve width, to provide maximum flexibility of lips E without breaking the sealing edges of these lips.

Furthermore maximum fiexibility is obtained with a minimum valve length. This means a saving of bag material. It is always desirable to have as short a valve as possible, commensurate with the ability of the valve to effectively seal against outfiow of material.

In view of the above, it will be seen that theseveral objects of the invention are achieved and other advantageous results attained.

As many changes could be made in the above constructions without departing from the scope of the invention, it is intended that all matter contained in the above description or shown in the accompanying drawings shall be interpreted as illustrative and not in a limiting sense.

I claim:

A bag structure comprising a tube having front and back walls and three parallel creases on each side to form oppositely located, inwardly directed gussets, diagonal creases within a gusset and in the walls at one corner of the bag providing for an end portion of said gusset being directed inward to form a valve composed in part of turned-in wall portions of the bag so as to form two panels for the top of the valve and in part of material turned in from the gusset so as to form two panels for the bottom of the valve, the material in the valve from the wall portions of the bag and that from the gusset portions being separated by two of said parallel gusset creases, and a pair of slits respectively at said last-named creases, each slit consisting of an opening formed by removing a finite area of material which includes part of the respective gusset crease.

ALBERT C. HAUNGS.

Images