US2863365A - Method of forming bags - Google Patents

Description

Dec. 9, 1958 T. E. PlAzzE 2,853,365

METHOD oF FORMING BAGS Filed Ooi.. 28, 1955 2 Sheets-Sheet l Dec. 9, 1958 T. E. PiAzzE 2,853,365

METHOD oF FORMING BAGS Filed oet. 28, 1955 2 Sheets-Sheet 2 INVENTOR.

BY View/@nd 9L Wm United Str-ttes Patent @hice 2,863,365 Patented Dec. 9, 1958 METHOD F FORMING BAGS Thomas E. Piazze, Mount Vernon, Ohio, assigner to Continental Can Company, Inc., New York, N. Y., a corporation of New York Application @ctober 28, 1955, Serial No. 543,411

Claims. (Cl. 931-65) This invention relates to receptacles and is more particularly concerned with improvements in a flexible bag having a drawstring closure and a method of forming the same.

In the packaging of fresh produce such as fruits and vegetables, or the like, bag-like containers have been provided which are generally of loosely woven fabrics with a drawstring type closure, since it is necessary to permit access of air to the packaged produce so that it may breathe and thus retain its life and freshness in flavor. Efforts have been made to provide bags or containers suitable for packaging produce which are formed of plastic films and perforated to provide the necessary ventilation. Such bags have been provided with drawstring closures of the same general character as the fabric bags which they are adapted to replace. However, it has been found diiiicult to provide a satisfactory plastic film bag with a drawstring closure which could be formed with sufficient economy to compete with the fabric bags, and, therefore, a general object of this invention is to provide a produce bag formed of plastic film and having a drawstring closure which can be fabricated in an economical manner and which has suicient strength in the closure to insure against tearing of the film material during the packaging operation and subsequent handling.

it is another object of the invention to provide in a flat or square bag formed of plastic iilm material a drawstring closure wherein the drawstring is encased in a bern formed by inturning the marginal edges of the bag mouth and seaming the same on the inside of the bag wall to provide a smooth exterior surface extending to the top of the bag.

Itis another object of the invention to provide a produce Hat or square bag formed of plastic film material and having `a drawstring closure wherein the drawstring is enclosed in a marginal portion of the bag material which is folded inwardly and attached to the inner surface of the bag material with the ends of the drawstring extending through an aperture provided in overlapped portions of the film which constitute a longitudinal searn formation.

It is another object of the invention to provide a method of forming a drawstring closure in a bag which comprises liattening a tubular section of a fiat or square bag forming material to bring opposed wallsinto superimposed relation, providing apertures in the walls adjacent the mouth forming end of the bag, threading a length of string which has its ends tied or otherwise connected to form an endless loop through the apertures, opening the mouth of the bag while it is on the string and folding the marginal portions of the bag material downwardly and inwardly between separated portions of the string and securing the same to the inner surface of the bag walls whereby to enclose the string portions within a hem formation at the mouth of the bag, and thereafter releasing one of the ends of the looped string to permit that end to be drawn through the aperture in the one wall of the bag while the other end of the loop projects through the aperture in the opposite wall of the bag and 1s readily accessible for closing the mouth of the bag. n

These and other objects and advantages of the lnvention will be apparent from a consideration of the bag structure and the method of forming the same which are illustrated in the accompanying drawings whereln:

Fig. l is a side elevation with portions broken away of a produce bag having incorporated therein the principal features of the invention; i

Fig. 2 is a perspective view of the top portion of the bag shown in Fig. 1 with the bag walls expanded into an open position ready for insertion of merchandise thereln;

Fig. 3 is a fragmentary side elevation to an enlarged scale, showing the apertured portion of the hem and the portions of the drawstring which project from the aperture;

Fig. 4 is a perspective View to an enlarged scale and with portions broken away of the top margins of the bag showing the perforated side walls;

Fig. 5 is a fragmentary perspective view, to an enlarged scale, showing the perforated top marginal portions of the opposed side walls and a looped drawstring inserted therethrough;

Fig. 6 is a side elevation illustrating the clamping of the ends of the looped drawstring after it is inserted in the apertures in the top ofthe bag walls;

Fig. 7 is a fragmentary section on an enlarged scale, of the bag top and the drawstring taken along the line 7-7 in Fig. 6;

Fig. 8 is a fragmentary, side elevation similar to Fig. 6 with the bag mouth expanded and a folding mechanism associated therewith;

Fig. 9 is a cross section on the line 9--9 of Fig. 8;

Fig. l0 is a fragmentary side elevation similar to Fig. 8 with the margins of the bag folded into the mouth of the same, and a backing plate for the sealing operation inserted between the two legs of the string; and.

Fig. 11 is a cross section on the line Il l of Fig. 10.

Referring particularly to Figs. l to 3 of the drawing, there is illustrated a produce container or bag l@ which incorporates therein the principal features of the invention. The bag lli is formed of a single sheet of relatively tlcxible heat scalable material having overlappingl side edges or margins 11 and l2 which are joined by heat sealing to form a seam 13 which extends axially or longitudinally of the bag. A `cross seal 14E- at one end of the bag it) provides a bottom closure which extends across the entire width of the bag. The bag lli which, as Shown in Fig. 1, may be collapsed into flattened condition, is provided with infolded or bellows sides as indicated at l5 and l5'. The film material from which the bag 10 is made is preferably a relatively thin, tough, transparent, continuous plastic such as polyethylene, Pliolrn or the like, which may b e folded as shown and which is readily heat sealed.

At the upper or top end of the bag section as shown in Figs. l and 2, the mouth ofthe bag is provided with a drawstring closure which includes a drawstring 16 in the form of an endless loop, and a marginal hem for1nation li in which the string 16 is slidably received, The hem formation 17 comprises a marginal portion l of the bag material which is folded inwardly against the inner face of the bag wall and seamed or sealed along the line 19 providing a guideway for the drawstring 16.. The drawstring lid has an end portion 2d which is accessible for the closure operation and which extends through an aperture 21 provided in the fold portion of the hemI 18 at the longitudinal seam location so that, as shown in Fig. 3, the aperture 21 is located in the overlapped longitudinal seam forming marginal portions 11 and 12 of the material and extends through a double thickness of the material at the seam 13. An aperture 22 is locatedA in the fold portion of the hem 15 opposite the aperture 21 which provides access to the drawstring 16 at opposite sides of the bag top in the event that it is desired to make two ends of the looped string available for tying across the top of the bag or container after it is closed or for any other reason.

In Figs. 4 to 1l, the preferred method of forming the 'drawstring closure in the mouth of the bag 10 is illustrated. As shown in Fig. 4, the top marginal portions of 'the opposite walls 23 and 24 of the flattened tubular section which is adapted to form the bag l@ are in collapsed and superimposed relation for simultaneously placing therein the apertures 2l and 22 which extend through both the side walls 23 and 24. After the apertures 2l and 22 are placed in the bag walls the drawstring i6 is threaded therethrough as shown in Fig. 5. The drawstring 16 comprises a piece of cord or twine of fibrous or plastic material, which may be in ribbon form, if desired, which is looped as shown in Figs. to 7 to provide two legs 26, 26 which are connected at one of their ends by a knot 27 or other fastening means. After the looped string 16 is threaded through the apertures 21 and 22 in the walls 23 and 24 of the collapsed bag 10, the closed knotted end 27 and the loop end 27 of the drawstring are positioned in holding or clamping members Ztl and 28 which are spread apart suiciently thereafter to draw the two legs 26 and 26 of the string 16 relatively taut as shown in Fig. 7. The side walls 23 and 24 of the bag top are then spread apart on the legs 26, 26 of the string 16 until the opened up end walls or bellows folds and 15 are brought into opposed relation, as shown in Fig. 8, beneath a pair of oppositely disposed pivoted tucking lingers 29, 29 which are mounted for rotation i' about the axes 30, 30'. The marginal portions f3 of the bag walls extend upwardly between the tuckingfingers 29, 29 and permit the latter to be rotated inwardly and downwardly of the body of the bag to reversely fold or tuck the film material in the margins i8 down inside of the bag and over or between the spread apart or spaced legs 26, 26 of the drawstring 16 which functions as a former for the folding. While the marginal portions T13 are held in the inwardly and downwardly folded condition a seaming or sealing operation is performed to secure the same to the adjacent inside wall of the bag. To provide an anvil for the sealing irons a plate-like form or backing member 31 is inserted into the mouth of the bag between the legs 2,6, 26' of the drawstring i6 as shown in Figs. l0 and 1l. With the anvil plate 3l positioned within the mouth of the bag, a pair of oppositely disposed movably mounted sealing irons 32, 32 are moved into engagement with the outer surface of the bag material to form the seam or seal 19. Thereafter the anvil plate 31 and the fingers 29, 29 are separated or withdrawn from the mouth of the bag and the string holding niembers 28, 28 are moved towards each other a sufficient distance to release the ends of the looped string lo and permit the knotted end 27 to be pulled sufficient to draw the looped end 27 of the string through the aperture 22 and into position for closing the bag or for permitting it to be refolded into the flattened condition shown in Fig. l for delivery to the user.

While the bag illustrated in the drawings is formed from a single sheet of material it may be of tubular form and the material may be duplexed or multiply. Also, the bag may be flat or square and formed with or without bellows folds as desired.

While specific materials and particular ldetails of construction are referred to in describing the illustrated form of the applicants bag, other material and other details of construction may be resorted to within the scope of the invention.

I claim:

1. A method of forming a drawstring closure in the end of a tubular bag section which comprises providing apertures adjacent the end of the flattened tubular section in opposed side wall forming portions, passing one end of a drawstring in looped formation through the apertures, positioning the end of the tubular section while. it is on the drawstring with opposite end wall portions 1n juxtaposed relation, folding the end margins of the tubular section over the portions of the looped drawstring which extend between said apertures and into the tubular section, and securing the infolded margins of the material to the inner walls of the tubular section at points inwardly of the drawstring portions to enclose the same in the hem which is formed thereby with the ends of the looped drawstring extending through the apertures.

2. A method of forming a drawstring closure in the end of a flexible tubular bag section which comprises providing apertures adjacent the end of a flattened end of the tubular section in oppositely disposed side wall portions thereof, passing one end of a drawstring in looped formation through the apertures so that the opposite ends of the looped drawstring extend outside of the same, shaping the end of the tubular section while it is on the drawstring by bringing end wall portions thereof into oppositely disposed relation, folding the end marginal portions of the tubular section in an axial direction inwardly of the tubular section between the portions of the looped draw string which extendbetween said apertures and securing said infolded portions to the inner walls of the tubular section in inwardly spaced relation to the drawstring to enclose the same in the hem which is formed thereby with a looped end of the drawstring extending through each of the apertures.

3. A method of forming a flexible bag with a drawstring closure in one end thereof which comprises overlapping marginal portions of a sheet of bag forming material and sealing the lsame to form a tubular section, bringing opposed wall forming end portions of the tubular section into flattened relation, providing aligned apertures in the end marginal portions of the flattened tubular section with one of the apertures in the overlapped seam forming margins of the material, passing one end of a drawstring in looped formation through the apertures, expanding and reforming the end of the tubular section and bringing opposite end wall portions into oppositely disposed relation with the apertures at opposite ends thereof and with the looped drawstring extending through the apertures, folding the end margins of the tubular section into the tubular section between and over the portions of the drawstring which extend between said apertures and securing said infolded margins to the inner surface of the walls of the tubular sec-V tion inwardly of the drawstring to enclose the same in the hem which is formed thereby with looped end portions of the drawstring extending through said apertures.

4. A method of forming a drawstring closure in the end of a flattened tubular bag section which comprises' providing aligned apertures adjacent the end of the attened tubular section in opposed side wall portions thereof, passing one end of a drawstring in looped formation through the apertures, expanding the tubular section while it is on the drawstring and bringing opposite end wall portions into juxtaposed relation, folding the end marginal portions of the tubular section into the tubular section between oppositely disposed leg forming portions of the looped drawstring and securing the edges of the infolded portions of the material to the inner walls of the tubular section to enclose the leg portions of the drawstring in the hem which is formed thereby.

5. A method yof forming a drawstring closure in the end of a flattened tubular bag section which is provided with aligned apertures adjacent the mouth forming end in opposed side wall portions thereof, passing one end of a drawstring in looped formation through the apertures, securing the opposite ends of the looped drawstring and placing the string under tension, expanding the tubular section -while it is on the drawstring and bringing 5 6 opposite end wall portions into juxtaposed relation, fold- References Cited in the file of this patent ing the end marginal portions of the tubular section in- UNITED STATES PATENTS wardly and downwardly between the oppositely disposed leg forming portions of the looped and tensioned draW- 231056 Kroebel.. Aug' 10 1880 String with the drawstring being used as a former, se- 5 781821 Glenwnght Feb 7 1905 curing the edges of the infolded portions 0f the material 835673 Pross Nov' 13 1906 to the inner walls of the tubular section to enclose the lltl'lse leg portions of the drawstring in the resulting hem and releasing the ends of the looped draw string.

Images