US1920700A - Paper bag - Google Patents

Description

R. W. JAITE Aug. 1, 1933.

PAPER BAG 2 Sheets-Sheet 1 Filed May 29, 1931 lf l I IN VEN TOR.

ROY W- .THITE A TTORNEY.

R. w. JAITE 1,920,700

PAPER BAG.

Filed May 29, 1931 2 Sheets-Sheet 2 INVENTOR.

R0 Y W'JR/ TE M. M M

llll llll IIIIII.

RTIQL Aug. 1, 1933.

ATTORNEY.

Patented Aug. 1, 1933 l n .i

, 1,920300 PAPER, BAG

Roy WV. Iaite,

Lakewood, Ohio Application May 29,1931..' SerialNo. 541,01 7 p 1 Claim? (01. 229-62) My invention relates to paper bags, and is an improvement pertaining moreparticularly to paper bags in which the opposite 'ends are closed. such for example, as in the so-called valve t yp'e in which the'bo dy of the bag is' composed of a multiple or plural'humber of flat tubes or tubular plies of paper, and provided with a self-closing valve in one angular corner. Such'bags are f'usually plicatedor formed with pleatedfolds at theirlongitudinal edges, and closed atboth ends, except for the valve openin'gin one corner. To .close such ends the general practice is to s'ew.the corresponding ends'of the plies of paper together,

- and 'also' to paste a binding striparound the end edges. Each tubular ply o f'paper also possesses a pasted longitudinal overlapping seam, the ends of. which are traversed by the stitches and united together and to"otheroverlapping plies in sewing operations. All the seams are located in the same side or in the same side Wall of the bag,

and though the seam in each successive tube is usually placed in laterally offset relation to the seams in the other tubes it follows that the bag is not of uniform thickness across each end where stitched or sewed on a straight line transversely of the bag. That is, the sewed stitches which extend across the vbag ends pass through successive areas of different thickness, inasmuch as each tube in the bag is of double thickness where seamed and only of singlethickness elsewhere, excepting at the'valve folds. In that connection be it known that the sewing needle passes through the thicker and thinner areas successively and punctures the paper at close intervals, and that the tension in the threads and on the paper may vary owing to the unequal thickness of the bag along the sewed line. y

For practical usages, paper bags of the described type are of substantial size, say approximately fifteen inches wide and twenty-six inches long in the flat. They areused extensively for transportation of powdered materials, for example, cement, and hold about ninety-four pounds net. To carry that weight these bags must be made of relatively tough paper and embodya suflicient number of tubular plies to protect the goods therein and withstand breakage andrupture, especially when the bags are being filled, and when picked up and handled. Owing to fre- 0 quent breakage, and loss of contents of such bags,

' the trade at present demands that such bags shall embody at least five tubular plies of paper of given quality and strength. However, different paper and a lesser number of plies of paper would sufiice'to make an acceptable bag, providing the bag would not tear or burst open especially in the region of the seams at oppositeends :there'of. My bjectin generaI is to provide a bag UN TE D STATE A T FF 1CIEQ made of the 'sameor a lesser number of plies than 7 as used and required heretofore,- which'jwill be stronger and more secure,xand- "overcome "the "known dangers and objections in'leakage, break- 'agefa'nd rupture in'thattypeof bag A further "object is'to prov-ideabag in which the ends are more rigidly united in sealing union without sewing -andwithout Qttaver'sing for perforating by stitching; that is, aba'giri which each plyiresists witlf its entire cross section breakage. and rupture, all as liereinafter--morfully described and pointed out :in the appended claim.

1 Inethe accompanying drawings, Fig. 1 is aside levatiom 'and 2 an edge, view, on a reduced scale; ofapaper bag embodyingkmy invention. Figs. 3 and 4 are enlarged sectional views on lines 33 and 4+4 of Fig. 1, showing the interlocking of: and sealing of the opposite walls at one end of the bag. Fig. 5 and Fig. 6, are obverse and reverse views of the same bag on a smaller scale,

portions of the successive tubular plies being broken away in stepped relation to show the internal construction within the opposite sides of the bag. Figs. 7,8, and 9,' are diagrammatic views, corresponding to cross sectional views on lines 7-7, 8-8, and 9 9, of Figs. 4 and 5, re-

spectively; Fig. 10 is a fragmentary perspective view of a sectional portion of the bag showing the sealing joint thereof.

Asa preliminary, it should be understood that in manufacturing multi-ply bags of the kind disclosed in the drawings, a series ofv sheets or'strips of paper are fed through a tubing machine. and creased or folded to forma multi-ply tube A hav-" so Y ing pleats orinwardly extending folds 2in-the longitudinal edge portions thereof. Thefsheets are fed into the machine in superposed relation with theirparallel edges offset or in stepped relation so that when the sheets are jointlyfolded to produce a. flat plicated tubular body thepar- :allel edgeportions of ,each sheet will overlap and to the paper along the edge thereof so that the overlapping parts of the seam in each sheet are united together. The tubular products thus embody a multiple number of seamed tubes, sleeved together'with the pasted seams 3 in the respecform longitudinal seams 3. Pasteis also appliecl thereof is folded inwardly to provide a valve in the form of an-open pocket or filling opening 5', the .inturned walls of which extend a given distance inwardly on lines substantially parallel with the'transverse end edge of the sleeved tubes. While severing the tubular product in short tubes of given length, the opposite ends 6 of-such tubes are simultaneously slit, preferably on converging lines '7, to form a number of tongues 8, which hesive covers each seal entirely, re-enforces same substantially and secures the tongues intheir folded position. 7

1 As previously delineatedall the seams of the bag are located on the same sideor in the same sidewall of the bag, so that one wall issubstantially re-enforced and thicker, even thoughthe seams are placed in laterally offset position; Any

. breakage of the'bag will therefore, of 'courseoccur in'the wall which is not re-enforced by the overlapping layers of a seam. To avoid such breakageand assure equal strength of both walls of the bag one orvmore' re-enforcing strips 10 of paper or other material are placed lengthwisenpon or within the plainflmseame'd ,wall r thesleve'd. tubes. The glengthot the re-enforcing strip 10;

only one of which is .used in the. three-ply bag shown in Figs. '5. through 8, corresponds to the length of the tubes so that-the opposite ends xthereof:will beconnected to and sealed with the corresponding ends of all the tubes. The width of strip 10 is more or less optional, but is preferably chosen to correspond with the total width of all three seams. The benefits and advantages of such an arrangement are made manifest as the body of the bag thus formed possesses the same or substantially the same resistance to tensile strains or stresses on both sides.

In manufacturing such bagsthe strip or strips 10 may be fed together with the several sheets of paper through the tubing machine, and the paste applied and the several sheets or plies folded and .severed concurrently with the strip or strips to provide a re-enforeed multi-ply tubular body of the requisite length from which to make a bag. The tucking of the valve and the sealing operations of the open ends of the bag may be per-- formed subsequently in another machine or in separate machines.

What I claim, is: V i A paperbag, comprising a multiple. number of seamed tubes, sleeved-together with their pasted seams longitudinally arranged on the same side of the bag, a re-enforcement strip of paper ex- 1 tending longitudinally upon the plain unseamed wall of the bag to the opposite ends thereof, a

pluralityof tapered locking tongues formedby' slitting the opposite ends of said tube and said re-enforcement strip on converging lines, said tongues being folded lalternately back'upon the opposite walls of said bag, and abinder strip pasted to and encircling the edge of said bag and covering said tongues, said tongues being of small width so that a'plurality ots'aid locking tongues extend over said re-enforcing strip to securely interlock said strip with the opposite ends of said bag.-

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