US3549084A - Shopping bags - Google Patents

Description

O United States Patent 13,549,0s4

[72] Inventor LeonardE.Canno 3,339,822 9/1967 Pearl 229/54 NewYork,N.Y. 3,353,741 11/1967 Kaminsetal...... 229/54 [21] Appl.No. 799,468 3,451,316 6/1969 Bagnall 93/35 Filed Feb'141969 Primary Examiner-David M. Bockenek [45 1 PauFmed 1970 Attorney-Sandoe, Hopgood and Calimfade [73] Asslgnee EquitableBag Co.,lnc.

Long Island City, N.Y. a corporation of New York [54] SHOPPING BAGS 6 Claims, 12 Drawing Figs.

[52] U.S. Cl. 229/54, 229/55;1 50/12 [51] Int. Cl. B65d 33/00 [50] Field olSearch 229/54, 55; 150/ 12 [56] References Cited UNITED STATES PATENTS 3,105,628 10/1963 Mack 229/54 ABSTRACT: Side weld plastic bags made with stifi'ened edges along the mouth of the bag by bonding stiffening or reinforcing strips to opposite longitudinal edges of the web or behind the edges from which the bags are to be made. This reinforcing is part of the continuous operation in which the web is folded and severed into separate bags. The product has modified forms that fold one stiffened or reinforced edge over the other, and has arrangements for providing a handle at the top of the bag connected with stiffening or reinforcing strips or formed by punching registering hand hold openings through the stiffening or reinforcing strips.

PATENTEU DEE22 mm SHEET 1 OF 2 INVENTOR ATTORNEYS.

III/III 1 1',

PATENTED utczzlsm SHEET 2 OF 2 W FIG. 9. J4

' LAsnc WEB SUPPLY BONDING STATION 50 *"HHEATER MAMA ATTORNEYS SHOPPING BAGS CROSS-REFERENCE TO RELATED PATENTS Side weld plastic bags have become popular for protecting various kinds of merchandise because the bags are made and sealed by methods that result in very low cost of manufacture. Some types have stiffeners at the closed top of the bag, but the bag has to be filled through the opposite end or open bottom. Prior to the invention of this disclosure, the side weld manufacturing techniques has not been used in any economical fashion for making shopping bags and similar holders that require provision for carrying the bag and that require some stiffness and protection against tearing at the mouth of the bag.

Patents showing prior art on side weld bags and their manufacture include the following: US. Pat. No. 2,971,874 Canno Feb., 1961, US, Pat. No. 3,361,041 Grob Jan., 1968, US. Pat. No. 3,381,592 Ravel May, 1968.

BACKGROUND AND SUMMARY OF THE INVENTION Side weld plastic bags, commonly made of polyethylene or polypropylene film, have been stiffened along their folded ends by placing a strip of cardboard or heavier plastic in the fold of the film; the resultant bags thereby being closed and reinforced on one end and open on the other opposite end. Such bags are filled through their open ends and they are then closed by sealing the open edges together.

These bags, even if made in large sizes, are not suitable for carrying bags or shopping bags because they are open at the wrong end or they do not provide for reinforcing for both sides at the open end against tearing or provide any handle portion by which the bag can be conveniently carried.

This invention provides a different construction for a side weld bag and a different way of making it. Instead of locating a stiffener in the fold of the plastic web, this invention applies stiffening strips to one or both of the longitudinal edge portions of the web. In the preferred construction the stiffening strip is applied to the edge portion far enough back from the edge itself to leave a free area of the web that can be folded back to cover the strip and to provide for bonding the folded material to the web back of the strip. After the edge portions are reinforced, the web is then folded to bring the edge portion on opposite sides of the web adjacent to one another to form the mouth of the bag. The reinforced edges are preferably cut to form notches spaced from one another by the extended width of the bags, and the individual bags are formed by melting through the folded web at the notches along transverse lines. This severing of the web welds the sides of the bags together on both sides of the line of melt in accordance with conventional practice.

The stiffening strips reinforce the mouth against tearing and to provide a stiff top for the bag for handles. A separate handle can be attached to the stiffening strip along each edge in position to be brought into register with the handle on the other side for convenient carrying of the bag with one hand.

In one modification, two stiffening strips are bonded to the plastic film along one side parallel to the edge but with one of the strips spaced inward from the other for a short distance so that there is plastic between them that forms a hinge on which the outer strip can be swung over the other edge of the bag and then downward to provide a folded top for the bag. Registering openings through the different strips can be used as a hand hold so that the stiffening strips can be gripped to serve as a handle for carrying the bag.

Other objects, features and advantages of the invention will appear or be pointed out as the description proceeds.

BRIEF DESCRIPTION OF DRAWINGS In the drawing, forming a part hereof, in which like reference characters indicate corresponding parts in all the views:

FIG. I is an isometric view, partly broken away and partly in section, showing a plastic web to which stiffening strips have been applied at opposite longitudinal edges in accordance with the first step of this invention;

FIG. 2 is a view similar to FIG. 1 but showing the web folded to bring the opposite edges and their stiffening strips into positions adjacent to one another;

FIG. 3 is a view, on a greatly reduced scale, showing the way in which the folded strip of FIG. 2 is cut out at spaced regions along the stiffening strips and severed into individual bags by melting through the folded web at spaced locations where the plastic is welded on both sides of the melted line of severance;

FIG. 4 is a greatly enlarged, fragmentary view, taken on the line 4-4 of FIG. 3;

FIG. 5 is a greatly enlarged sectional view showing the way in which handles are applied to the front and back panels of the bag shown in FIG. 3;

FIG. 6 is a view similar to FIG. 5 but showing a modified form of the invention in which two stiffening strips are applied to one edge of the bag and one edge is folded over the other and hand hold openings are provided for carrying the bag;

FIG. 7 is a fragmentary side elevation of the modified construction shown in FIG. 6; I

FIG. 8 is a sectional view of the modified construction shown in FIG. 6, but showing only the upper part of the web and showing its position before folding the web at the hinge line between parallel and spaced stiffening strips;

FIG. 9 is a diagrammatic view showing the method by which the bags of this invention are made;

FIG. 10 is a top plan view of part of the structure shown in FIG. 9, the view being taken along the line 10-10 of FIG. 9;

FIG. 1 l is a side elevation, at the line 1 1-11 of FIG. 9, showing more of the apparatus of FIG. 9; and

FIG. 12 is an enlarged sectional view taken on the line 12-12 of FIG. 9.

DESCRIPTION OF PREFERRED EMBODIMENTS FIG. 1 shows a plastic sheet or web 10, which is preferably made of polyethylene, and to which stiffening strips 12 are applied along the opposite longitudinal edges of the web. The strips 12 are preferably made of cardboard since this material provides the necessary stiffeners and is economical. The stiffening strips 10 are bonded to the web 10 over their confronting faces by applying heat, paste or or other adhesive, or combinations of adhesive and heat to the portions of the web 10 that contact with the strips 12. If the web 10 is made of material which cannot be heat sealed to the stiffening strips, the surface bonding can be obtained entirely by coating the strips 12 with adhesive.

Other material than cardboard can be used for the strips 12. Plastic of a thicker gauge than the web 10 can be used, but the strips 12 should be of sufficient stiffness to prevent the bag from sagging when loaded to its intended capacity as will be more fully explained.

In the preferred construction, the strips 12 are bonded to the web 10 far enough back from the actual edge to leave enough width of material to fold back across the strip and to bond to the web behind the strip as shown in FIG. 2.

FIG. 2 shows the web Ml folded over along a longitudinal foldline M which is in the center region of the web and at the actual center in the case of FIG. 2. This folding of the web produces a front panel 16 and a back panel 118. In order to make the web into separate bags, the folded web 10 is severed along lines 20 which extend transversely of the web and preferably normal to the longitudinal edges and to the fold line 14. These severed lines 2t) are spaced from one another by a distance equal to the desired width of a bag 22.

When the bags are made of polyethylene, or equivalent plastic sheets, the lines of severance can be made by applying heat to the plastic so as to melt through both the front and back panels of the folded web. At both sides of the region where the plastic is melted through, the front and back panels are heated to a welding temperature so that areas 24 along the sides form side welds connecting the front and back panels.

Since the stiffeningstrips 12 are ordinarily made of material which cannot be melted when severing successive bags from one another, a cutter is used to sever the bags at the regions of the strips 12. The cut made through the strips 12 can be a simple cut in line with the severance line 20 for each bag; but in the preferred construction, cutout area or notch 28 is used at a location ahead of the severing station, and at what will be the top of each severance line 20.

The cutout area 28 extends downward from the edges of the folded web for a distance slightly greater than the width of the stifiening strips 12 and extends longitudinally for adistance equal to the desired width of opening of the mouth of the bag. Since half of each cutout area 28 is in one bag and the other half is in the next bag, the cutout corner at each side of an individual bag extends'for a distance equal to one-half of the intended width of the mouth opening; but since this cutout comer is both in the front and back panel, the total spacing to the front and back panel when the bag is pulled open to the extent permitted by the cutout corners is equal to approximately twice the longitudinal length of the cutout in each panel.

The strips 12 aresufficiently'stiff to resist bending of the portions of the front and back panels which lie below the strips T when the bag is-in an upright position, and the strips 12 are stifi enough to prevent any substantial sagging of the mouth of the bag when it is carried by handles 32 and 34 attached to the stiffening strips 12 and the overlying portions of the web 10.

' FIG. 5 shows the handle 32 attached to the front panel 16 by fastening means comprising staples 36. These staples extend through the handle 32, strip 12 and plastic 10, and two staples are shown at each end of the handle 32 in the construction illustrated in FIGS. 3 and 5. The handle 34 is similarly In the preferred construction, snap fasteners are provided for holding the handles 31 and 32 together when the bag is closed. FIG. 5 shows a snapfastener consisting of protuberance 38 extending from the'handle 34 toward the handle 32.

-'lhere is a complementary opening 40 in the handle 32 into which the protuberance 38 snaps when the handles 32 and 34 are pressed together. There are two such snap fasteners, designated by reference character 42, on the bag shown in FIG. 3.

1 When the handles 32 and 34 are made of molded plastic, as is the case in FIG. 5, it is economical and effective to make the protuberances 38 a part of the handle molding and to mold the handle 32 with openings 40 in line to register with these protubierances 38. If the handles 32 and 34 are made of other material or by other methods, and it is desired to have snap fasteners, they may be applied to the handles in any conventional way.

FIGS. 6-8 show a modified construction in which parts corresponding to FIGS. l-4 are indicated by the same reference characters with a prime appended. The web 10' has stiffening strips 12' applied to its opposite longitudinal edges as' in the case of FIG. 1, and it also has a second stiffening strip 12a applied to it parallel to one edge and parallel to the strip 12 but spaced a slight distance from the strip 12' so as to leave a relatively narrow width of plastic between the strip 12' and 12a to form a hinge 44.

The web is folded longitudinally in the region of its center but not exactly at the center. The stiffened edges are offset sufficiently to permit the edge of the front panel 16, which has the two stiffening strips 12 and 12a, to fold over the edge of ,the back panel 18 as shown in FIG. 6. Aligned hand holes 46"through the strips 12' and 12a and the overlying areas of the, plastic 10' provide the handle by which the bag of FIGS. 6- -8 is carried.

FIGS. 9-12 illustrate diagrammatically the method for making the bag shown in FIGS. I-S. The web 10 unwraps from a supply reel SOand passes over guides 52 to a folder 54 at which the web is folded along its longitudinal center line.

1 As the web 10 travels from the supply reel 50 to the folder 54, the stiffening strips 12 are withdrawn from strip supply spools'56 and are brought across guides 58 into contact with the web 10 at a bonding station 60. In the construction illustrated the strips 12 and web 10 pass over a roller 62 at the bonding station 60; and heater shoes 64 press the web into contact with the strips with sufficient heat and pressure to bond the strips 12 to the web 10.

The folded web passes around successive guide and feed rolls 68 of a'loop accumulator and the folded web advances intermittently to a cutoff station 70. The continuous operating feed rolls of the loop accumulator are driven directly from a motor 72 and the intermittently operated feed rolls can be driven from-the same motor through intermittent driving means 74. This mechanism is conventional for plastic bag making machines and no details of its construction are necessary for a completed understanding of the invention.

At the cutoff station 70, the folded web passes over a roll 78, and there is a heater which is moved intermittently by motors 82 into contact with the folded web to melt the plastic and sever individual bags from the folded web as previously described.

The web cannot be melted through at the regions where the stiffening strips 12 are bonded to the plastic of the web; and the notches 28 are cut through the plastic and stiffening strips by a cutter 84 operated by a notcher 86 at a notching station 88.

Beyond the cutoffstation 70, the bags 22 are picked up by an endless belt conveyor 90 driven by a motor 92 in accordance with conventional practice. The conveyor 90 carries the bags to a collector station where they are bundled for shipment.

The preferred embodiments of the invention have been described, and the invention is defined in the appended claims.

I claim:

1. A side weld plasticbag made of plastic sheet material and including front and back panels connected with one another at their lower ends, and connected with one another along their side edges by-welds of the plastic sheet material, a mouth at the upper end of the bag, stiffener strips that reinforce the mouth of the bag, the stiffener strips being secured to the upper portions of both the front and back panels and each of the strips extending generally parallel to said lower ends of the front and back panels, each of said strips having an area starting adjacent to the top of the bag and extending downward for a limited'distance toward the bottom of the bag and across the full widtliof the top of the bag on one side thereof, and a handle of substantially less extent than the width of the top of the bag and located at the stiffener strips for supporting the bag by said stiffener strips.

2. The plastic bag described in claim 1 characterized by the handle having a lower part covering an area of one of the stiffener strips and connected with said stiffener strip, the upper portion of the handle extending above the stiffener strip and having a grip portion above the stiffener strip and by which the bag is carried.

3. The plastic bag described in claim 1 characterized by handles connected with both sides of the bag at the stiffener strips, and snap fastener means on the handles for detachably connecting the handles together to hold the bag closed.

4. The plastic bag described in claim 1 characterized by the stiffener strips being made of paper board secured to the plastic sheet material by folding the sheet material over the upper edge of the stiffener strips and back down beyond the lower edges of the stiffener strips and bonding the sheet material to itself beyond the lower edges of the stiffener strips.

5. The side weld plastic bag described in claim 1 characterized by handles of plastic material secured to the stiffener strips, the stiffener strips being secured to the handles by metal fastening means which extend through the plastic and stiffener strips at the mouth of. the bag and through the handles, and the handles having a snap fastener means for holding equal to the intended spacing of the front and back panels at the mouth of the bag when the bag is filled, and for a distance downward from the top of the bag greater than the height of the stiffener strips.

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