US2045585A - Valve bag and method of making the same - Google Patents

Description

June 30, 1936. T. E. COTY VALVE BAG AND METHOD OF MAKING THE SAME Original Filed Nov. 4, 1953 2 Sheets-Sheet 1 INVENTOR.

ATTORNEY.

Original Filed Nov. 4, 1953 2 Sheets-Sheet 2 ATTORNEY.

Patented June 30, 1936 UNITED STATES VALVE BAG AND METHOD OF MAKING THE SAME Thomas Earl Coty, Watertown, N. Y.

Application November 4, 1933, Serial No. 696,704 Renewed September 27, 1935 17' Claims.

My present invention relates to bags, particularly paper bags; and especially to the so-called valve bag" which is usually made of a number of sheets of heavy paper constituting a multiple wall web, blanks from the tubes formed from the web being cut off and having one end folded and sealed in a bottoming machine, while the other endis folded and left unsealed at one side to form a valve opening so that granular or pulverulent materials such as cement, sugar or the like, may be injected into the bag by suitable means through a tube inserted in the valve.

These bags are old and well known, but usually made they are subject to a serious objection in that with some forms of material (particularly those which are not powdered such as granulated sugar, or the like) the closing of the valve by the weight of the material is not entirely efiective, so that there is more or less leakage waste sifting out and which is highly objectionable in the case of food products for sanitary reasons as well as by reason of expense through wastage.

The present invention overcomes the difficulty by sealing the valve after the bag is filled, so that there is no waste whatever in ordinary practice, except such as may be incident to the filling operation. The bag as a whole, after it is sealed, is hermetically closed and may be handled without spilling the contents after leaving the factory in which it is filled.

To effect the ends pointed out I cut in the web or in the outer ply thereof, a sealing flap and preferably reinforce the place from which the flap has been cut from the web by means of a strip of material, generally paper, which is secured over the opening formed by the flap. When the valve end is formed in the bottoming ma-,

mechanismv for making it. Suh mechanism forms matter for another application.

In general, the bag resemblesfthose which I have disclosed in my prior patent, No. 1,903,285, issued April 4th, 1933, for what is known in, the trade as a "sift-proof bag. This discloses. one way in which the bag may be closed at one end, although I may also employ the construction shown in my parallel pending application, Se-

rial Number 672,717, filed May 24th, 1933, for

what is known in the trade as the cut-out bottom" bag. This construction has been applied to a large number of valve bags, in fact to many millions of them, and the sealing of these after filling is the principal object of the present invention, as already pointed out.

The accompanying drawings show an embodiment of the invention; they illustrate also the steps of the process of manufacture, which I aim to cover by "art" claims.

In the drawings:'

Figure 1 is a portion of a web showing the sealing flap already cut, before the web is formed into a tube. I

Figure 2 is a bag-blank or tube cut off from the web showing the flap at one of the folded edges of the tube with the reinforce applied there.

Figure 3 shows the shape of the reinforce when it has been applied; and Figure 3 when opened.

Figure 4 isa cross-section of the blank shown in Figure 2, on the line 4-4.

Figure 5 shows the end of the blank shown in Figure 2 on a somewhat larger scale, after one 2 of the sift-proof notches has been formed.

Figure 6 shows the next step of formation of the valve bag when the bag end is opened with two of the sides folded in, but before the other two sides are folded.

Figure 7 shows the formation of the valve-end of the bag, with my improved end inopen position.

Figure 8 is a view showing the introduction of the tubeinto the valve.

Figure 9 shows how the sealing of the flap is folded to complete the seal of the valve; and

Figure 10 is a view of the complete bag with the valve opening closed and sealed according to the invention.

Figure 11 is like Figure l, but the reinforce is omitted.

Figures 12 and 13 show a slit in the ply A of the web, instead of the reinforce.

Figures 14, 15 and 16 are parallel .to Figures 5, '7 and 8, with the reinforce removed.

Figures 17, 18 and 19 are like Figures 8, 9 and 10, with the slit in web A substituted for the prior construction with a reinforce.

To one familiar with the art the drawings are almost entirely self-explanatory.

In Figure 1, A is the upper sheet of a multiwall web; A and A" indicate other sheets which go to form the web. There may of course be more than three sheets, or the bag may be formed of. a less number.

h At B is shown the flap cut from one of the sheets of the web, while B shows the opening made by the cutting of the flap, and C shows the reinforce which may be afterwards applied at this point.

The reinforce is shown in Figure 3 and it may be applied in a flat form on the web shown in Figure 1, or it may be folded, as shown on the right in Figure 3, and applied to the edge of the v and shows at D the notches, formed in one end of the tube, before said end is folded to form the sift-proof seal of my patent already referred to; E, E are the portions which form two of the closure flaps, and F, F are the other two closure flaps, before folding. These flaps are shown completely closed in Fig. 7.

Figure 6 shows the first stage of opening the bag bottom so as to be ready for sealing the bag. Figure '7 shows the valve-end sealed except for the closure to be made after the bag is filled, and the parts are marked as before. The reinforce is here shown in dotted lines because it is beneath the folded ends of the valve, and opening B is shown in dotted lines because it is behind the reinforce C.

In Figure 8 the parts are as before, but here the tube of the filling machine is shown atG.

In Figure 9 the tube has been withdrawn and the fiap B is being closed, after paste has .been applied thereto in any convenient way, by the finger of the operator.

Figure 10 shows the bag completed, broken away for convenience of illustration.

I have pointed out in my statement of invention that the construction employing the reinforce C is preferred, as the seal is stronger when so made; but it is not essential to the invention, which is not limited in that respect. On the contrary, I may effect the seal by cutting the flap in the outer ply as before, but instead of applying the reinforce over the hole and sealing the flap thereupon I cut a slit in the next layer of the web, near the base of the flap, and after the bag is filled I seal the fiap over the slit, thus effectively sealing the bag. In Figures 1 to 19 this form of closure is shown; these figures are parallel to Figures 1 to 10, except that Figure 4 is not repeated. In all these figures the steps of construction are as already described with reference to the reinforce" type of seal. In them the slit is shown in the ply A of the web, and is lettered H. As shown it is located near the base of the flap, and is of such a length as will permit its being sealed over its entire length when the flap is secured, in general being a little shorter than the fiap on its line of measurement. It must evidently be long enough to permit the insertion and withdrawal of the spout G of the filling machine; otherwise its precise location and size are subject to variation. The reference letters in Figures 1 to 19 indicate the same parts as in Figures 1 to 10; detailed description seems unnecessary. Ply A is pasted to ply A so that the slit opens when A is lifted, permitting the insertion of the spout G, as shown in Figures 16 and 17, for example. This pasting is sufliciently far from the slit H to permit the flap Bto bepassed between the plies when the valve is sealed by closing the flap, as shown in Figures 18 and 19.

The method of forming the bag will be apparent from these figures. It consists in cutting a flap in the web and closing and sealing the flap after the bag is filled. Also as a specific form of the method of operation, it consists in cutting the fiap as already described, and then covering the opening made by the fiap by means of a reinforce, this being effected either while the web is fiat and before it is formed in the tuber, or after the web has been folded, and either before or after the blank has been separated from the rest of the web.

- As a further detailed process of manufacture, the multiwall form of bag is formed by assembling several plies of material, usually heavy paper, into a web, cutting a flap in the outer ply, by preferenceleaving one side of the flap attached to the web, applying a reinforce over the hole or cutting a slit in the next ply of the web, folding the valveend of the bag and in so doing pasting the upper surface of the reinforce or of the second ply to the upper ply leaving the crack between the flap terials. It may also be used with good efiect' for bags containing pulverulent materials.

What is claimed is:-

1. The improvement in the art of sealing folded and pasted valve-bags, which consists in forming a flap in the web; folding the web in the tuber so that the flap is left upon one side at the valve-end of the blank; then folding and sealing the folds to close the valve-end, leaving the flap open for the insertion of the filler tube; and finally sealing the valve-end by closing and sealing the flap against a co-operating surface after the filling is complete.

2. The improvement in the art of making valve-bags, which consists in forming a fiap for sealing the valve, applying a reinforce adjacent to the fiap, and sealing the fiap upon the reinforce, thereby sealing the valv as described.

3. The improvement in the art of forming valve-bags, which consists in assembling several plies of material into a web; cutting a fiap in the outer ply of the web, leaving one side of the flap attached to the ply; applying a reinforce to the opening made by cutting the flap; folding andpasting the valve-end of the bag; securing the upper side of the reinforce to the folds of the valve-end, leaving the opening between the fiap and reinforce ready for the spout of the filling machine, and the flap and reinforce available to seal the valve end, as described.

4. As a. new articleof manufacture, a multiply valve-bag provided with a flap for sealing the valve-end and a reinforce over the opening made by the cutting. of the flap.

5. As a new article of manufacture, a valvebag having a flap cut in 9. ply of the web; a reinforce over the opening left by the cutting of the flap; the flap and reinforce co-operating to close the valve opening when sealed together, as described.

6. A folded and pasted valve-bag provided with means for sealing the valve after the bag has been filled, such means comprising a flap cut in a .ply'oi the bag, and means co-opera with the flap to effect the seal.

'1. A multl-wall bag provided 'with means for sealing the valve after filling the bag, comprising the opening from which the'flap is cut, the reinforcing piece being sealed on its upper side to the folds of the valve-end of the bag; whereby the space between the flap and the reinforce constitutes an entrance for the tube of the filling machine, and sealing the flap and the reinforce together seals'the valve-end of the bag, as described.

8. A multlwall blank from which a valve-bag is to be formed, having on one edge a flap cut from the outer ply of the wall, a flap being attached at one side to the wall, and a reinforce covering the hole where the flap was cut; the flap and reinforce constituting a sealing means for the valve-end.

9. A blank for forming folded .and pasted valve-bags, comprising a multiwall tube having a valve opening and an integral sealing flap cut from a ply of the blank, said flap being 11031- I tioned to overlie the valve opening, and a surface against which the flap may be pasted to seal the valve-opening.

10. A blank for forming a folded and pasted" valve-bag, comprising a flattened multiwall tube having a valve opening, said tube having an integral sealing flap out near an edge thereof from a ply near one end of the blank, the flap arranged to, co-operate with the surface formed by another ply to close and seal the valve-opening after the bag is tilled.

.11. A blank for forming a sealed v'alv e-rbag, comprising a tube having a sealing flap near one end positioned to overlie and seal the valve opening, and a reinforcing strip secured to the tube adjacent the flap.

12. A blank for forming a valve-bag, compris an integral sealing flap cut from an edge thereof near one end and adapted to close the valve opening when said end is folded to form the opening, and areinforcing strip adhesively attached to the tube adjacent the sealing flap.

14. As a new article of manufacture, a pasted valve-bag having a folded end and with a portion thereof unsealed to provide a valve-opening, a sealing flap cut -from a ply of the bag and overlying the valve-opening, the flap co-operating with the surface of another ply to close and seal the valve after the bag is filled.

15. As a new article of manufacture, a multiwall bag formed from a tube having one end' closed and another end folded and pasted to form a closure having a valve opening, and a "sealing flap cut in the outer ply of the wall adapted to overlie and close and seal an opening in the next ply by being pasted against the surface of the said ply. g

16. As a new article of manufacture, a multi- -wall bag formed from a tube having one of its ends folded and pasted to form a closure and a valve opening, and a foldable sealing flap formed from a ply of the multiwall tube and adapted to overlie and close and seal thevalve opening by being pasted against the surface of the nextply. I i

17. As a newarticle of manufacture, a valvebag having a folded end with a portion thereof unsealed to provide a valve opening between the folds, a reinforcing strip secured to the folded end. of the bag at said opening, and a sealing flap adapted to be adhesively' attached to said strip to-close and seal the opening.

, I THOMAS EARL COTY.

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