Bag bundling system

Abstract

A tab for mounting a bag bundle on a retaining hook of the type having an upwardly bent hook is shown configured in a bundle of bags. The bundle of bags has at least a leading bag and a plurality of trailing bags. There is at least one tab attached to one bag wall of each bag. This tab is in alignment with like tabs from like bag walls. The tab includes a flanged aperture including at least one peak, with this peak protruding inwardly toward and to the aperture for contact with the upwardly bent hook whereby the tabs are bent out of alignment with the upwardly shaped hook.

Description

CROSS-REFERENCES TO RELATED APPLICATIONS

[0001] Attention is directed to my U.S. Pat. No. 6,171,226, issued Jan. 9, 2001 entitled Plastic bag bundling system. This application includes an improvement related to that invention.

[0002] This application claims priority from Provisional Patent Application No. 60/268,265, filed Feb. 12, 2001 by the name inventor entitled Plastic Bag Bundling System, Attorney Docket No. 019183-000310US, is likewise incorporated by reference as if fully set forth herein.

[0003] This invention relates to self-opening plastic bags and the related dispensing systems. More specifically, this invention relates to an improved self-opening system or a manner to improve existing self-opening systems.

STATEMENT AS TO RIGHTS TO INVENTIONS MADE UNDER FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT

NOT APPLICABLE

REFERENCE TO A “SEQUENCE LISTING,” A TABLE, OR A COMPUTER PROGRAM LISTING APPENDIX SUBMITTED ON A COMPACT DISK.

NOT APPLICABLE

BACKGROUND OF THE INVENTION

[0004] Common self-opening systems used today have an open bag mouth at the top and are of the bottom seal variety, which are gusseted along their sides, or of the sideweld variety, which may be gusseted along the bottom. Most of these bags have carrying handles, most of which are of the strap variety or die-cut holes near the bag top. These bags are typically stacked up in the manufacturing process and are then selectively bonded into bag packs of 50 to 100 bags, thus forming a pack of self-opening plastic bags as is well known in the art.

[0005] As described in U.S. Pat. No. 4,676,378 Baxley, et al, adhesives may be used to cause plastic bags to self-open when dispensed from their T-shirt rack holders, such as the rack in my U.S. Pat. No. 4,821,985. As described in U.S. Pat. No. 5,183,158, Boyd and U.S. Pat. No. 5,562,580, Beasley, et al., cold seals may selectively cause the self-opening of the next bag in sequence. The key to using cold seal processes for selectively bonding bags in a bag pack is revealed in my U.S. Pat. No. 5,013,290, which discusses having an inside bag surface with low coefficient of friction and an outside surface with a high coefficient of friction. This selective bonds the high coefficient surfaces together.

[0006] Beasley, et al in U.S. Pat. No. 5,335,788 illustrates the use of cold seals applied to the tops of plastic bags which cold seals may also be used to bond the plastic grocery sacks together in bag packs. Many other means of using cold seals for selectively bonding bags in a self-opening bag pack are illustrated in U.S. Pat. No. 5,863,130 Nguyen, U.S. Pat. No. 5,967,662 Chew, U.S. Pat. No. 5,996,801 Tsu, and so on.

[0007] Commonly known in the plastic bag manufacturing industry, a bond at the die cut region which forms a bag mouth and may also form the extended handles of a T-shirt style bag, may induce a self-opening effect on properly treated surfaces. However, this is generally a weak bond and insufficient to cause standard plastic bags to self-open on a rack. This is particularly true with the new aperture bag styles, such as that of U.S. Pat. No. 5,845,779 Wilfong, et al. The key reason is that the aperture tabs tend to bind on the retaining hook, thus fighting, at times defeating, the self-opening effect. Thus, the newer aperture bag styles must have relatively strong self-opening bonds else they will not self-open. Bags that use adhesives will tend to work better than the cold seal bonds of bags of the '788 variety, because adhesives tend to form stronger bonds between the successive bag walls.

SUMMARY OF THE INVENTION

[0008] A tab for mounting a bag bundle on a retaining hook of the type having an upwardly bent hook is shown configured in a bundle of bags. The bundle of bags has at least a leading bag and a plurality of trailing bags. Each bag of the bundle of bags has a front bag wall having a top, a bottom, and two parallel side edges; a rear bag wall having a top, a bottom, and two parallel side edges; two bag sides. Each bag side joining one of the side edges of the front bag wall to one of the side edges of the rear bag wall. The bag forms a closed continuum around the front bag wall and the rear bag wall. A bottom joins the bottom of the front bag wall and the bottom of the rear bag wall to form a closed bottom to the closed continuum of the bag. There is at least one tab attached to one bag wall of each bag. This tab is in alignment with like tabs from like bag walls. The tab includes a flanged aperture including at least one peak, with this peak protruding inwardly toward and to the aperture for contact with the upwardly bent hook whereby the tabs are bent out of alignment with the upwardly shaped hook. The tab for mounting a bag bundle on a retaining hook can include a slit partially severing the tab overlying the triangular shaped aperture.

[0009] The bags of present invention refer to a simple means of relieving the binding effect of aligned aperture bags so that a minimal bond is required to cause a bag to self-open, regardless of whether adhesives or one of the previously referenced cold seals are used. This is accomplished by using a non-binding, severable aperture.

[0010] The chief benefits to using a non-binding aperture are that it will increase self-opening reliability, and will do so by reducing the amount of adhesive required, or reduce the cold seal surface required to bond the outer bag surfaces together. It will also reduce the cost of dies, which may have only 1 or 2 cold pressures seal instead of 6 or 8, or; the present invention may completely eliminate the need for pressure seals altogether as will be described in further detail herein.

[0011] The bags of the present invention can be made on existing bag machinery and produced at high speeds with minor modifications. For ease of explanation, only a few particular forms of the present invention will be discussed herein, however, it would be easy for anyone trained in the art to find other related applications, which would fall under the scope of the present invention.

BRIEF DESCRIPTION OF THE DRAWINGS

[0012] FIG. 1 is a plan view of the version of a non-binding, severable aperture, suitable for mounting onto a U-shaped retaining hook like those typically found on T-shirt bag racks set forth in my U.S. Pat. 6,171,226 issued Jan. 9, 2001 entitled Plastic bag bundling system.

[0013] FIG. 2 is a perspective view illustrating how the aperture in FIG. 1 avoids binding on a horizontal U-shaped retaining hook.

[0014] FIG. 3 is a perspective view of a pack of T-shirt bags incorporating the aperture of FIG. 1 and being dispensed from a rack.

[0015] FIG. 4 is a plan view of a variation of a non-binding, severable aperture that may be suitable for mounting onto a single retaining hook which is specifically claimed and set forth in this application.

[0016] FIG. 5 is a perspective view illustrating how the aperture in FIG. 4 avoids binding on a single retaining hook.

[0017] FIG. 6 is plan view of an aperture that may also be mounted in a non-binding manner on a retaining hook.

[0018] FIG. 7 is a perspective view incorporating the aperture of FIG. 6.

DESCRIPTION OF THE SPECIFIC EMBODIMENTS

[0019] In FIG. 1I illustrate bag support as set forth in my U.S. Pat. No. 6,171,226 issued Jan. 9, 2001 entitled Plastic bag bundling system. In FIG. 1,, the top portion of a single bag is shown. Aperture 10 has a top 12, a left side 14, a right side 16, an inwardly extending flange 18 on the left side 14 and an inwardly extending flange 20 on the right side 16. Above top 12 is a pre-weakening slit 22 in the bag film, which typically would be cut about {fraction (1/16)}″ away from the top edge 12 to allow for easy severance. Pre-weakening slit 22 may also be situated about {fraction (1/16)}″ below the bag mouth edge 24.

[0020] There are a number of ways that a tab or aperture portion may be pre-weakened, as revealed in any number of prior art patents. What is important is to have a aperture tab sufficiently pre-weakened at a point near the aperture and the bag mouth, in order to allow for severance and the entraining of the following bag in sequence, but not too aggressively pre-weakened that it causes a multiple dispensing—paper doll—effect. A pre-weakened point may be set at the end of the aperture's die cut line or at any point along its edge. It may also be along the bag mouth itself facilitating the propagation of a tear into the aperture. In the case of the present invention, it is irrelevant what type of pre-weakened means is used since the location and type is not a requirement of the present invention. Besides, all aperture tabs must have some form of means to tear loose from a retaining hook, else it would not serve it's basic, fundamental purpose. In the center of the aperture is film portion 26. In this figure, the ends of sides 14 and 16 are curved back upon themselves and point inward at a direction that will help relieve the possibility of tearing the thin plastic film at the end of the die cut. This form of aperture may be used as the central releasable portion for common grocery sack T-shirt bags, on extended portions, or may be used in any number of bag or film applications in which severability of the bag or film is desirable, instead of using a detachable tab. This particular aperture may also incorporate the releasable bonding means of a bag pack further described herein in FIG. 3.

[0021] In FIG. 2 aligned apertures 30 are the same as aperture 10 of FIG. 1, located near the aligned bag mouths 44, forming a aperture tab 31, which aperture and tab is mounted onto a U-shaped retaining hook 48. When mounted on retaining hook 48, the flanged shape of aligned apertures 10 causes the inwardly extending flanges 38 and 40 to turn up spacing the forward-most bag wall 50 away from tines 54 and 56 of retaining hook 48. Thus, the forward-facing wall surfaces (only forward-facing wall surface 50 of forward-most bag 52 is shown) of the bag walls of the aperture apertures 31 do not come into direct contact with tines 54 and 56 of retaining hook 48. Subsequently, when forward-most bag 52 is dispensed from retaining hook 48, the forward-facing bag wall surface 50 will not bind on or against tines 54 and 56 of retaining hook 48, thus allowing the bag wall to easily separate at the pre-weakening slit 42. As shown, the upturn of flanges 38 and 40 have caused the rear-facing wall surfaces 58 and 60 to rest against tines 54 and 56 instead. On a narrower retaining hook, or a single hook, this type of aperture may instead cause the inner edges 62 and 64 to come in contact with the retaining hook, which produces substantially the same result. The center film portion as described as 26 in FIG. 1 is not shown in order to more clearly illustrate this non-binding phenomenon, and will also be eliminated in related future drawings.

[0022] In FIG. 3, aperture tabs 91 of bag pack 101 are mounted on a common dispensing rack (partially illustrated) by mounting aligned apertures 70 onto retaining hook 88 and aligned handle hole apertures 81 and 83 onto rod supports 85 and 87 respectively. Aligned apertures 70 are resting upon retaining hook 88 as similarly illustrated in FIG. 2 with left flanges 78 and right flanges 80 turned up in a non-binding manner and not in direct contact with left side tine 94 or right side tine 96. Forward-most bag 100 has front wall aperture tab 111a and rear wall aperture tab 111b completely severed from retaining hook 88 and has been pulled forward a sufficient distance in order to effect the self opening of the next bag in sequence 130. Self-opening is accomplished by the entraining effect between the selective bonds between the outer film layers of successive bags in the bag pack as is commonly known in the field. In this example, the selective bond has been formed by the die cut that has formed the aperture tab at location 120, hence bonding the rear wall aperture tab 111b of forward-most bag 100 to the forward wall aperture tab 111c of next bag in sequence 130. This is a relatively weak bond compared to the cold seal bonds of U.S. Pat. No. 5,335,788, but is sufficient to effect self-opening in conjunction with the non-binding apertures of the present invention. Instead of selectively bonding successive bags in this manner, they may also be selectively bonded at the apertured handle holes 81 and 83, or may be selectively bonded together with a single cold seal bond at location 114, or may be simply, selectively bonded at the aperture die cut itself. In all cases, the adhesion strength of the bonds required is substantially reduced due to the non-binding apertures.

[0023] In FIG. 4 aperture 130 has a left side edge 134, a right side edge 136, and is located directly below bag mouth 144 in top aperture portion 146. Left side edge 134 and right side edge 136 turn upward at their ends, thus forming a single, horizontal, downwardly positioned flap 138, defined by horizontal die cut edge 140, which utilitarian value will be illustrated in FIG. 5, which value is identical to that of the left side and right side flanges illustrated in FIGS. 1, 2 and 3. In the spirit of the design and performance of the aperture of FIGS. 1, 2 and 3, aperture 130 has a pre-weakening slit 142 in order to allow for easy severability of a tab from a retaining hook.

[0024] In FIG. 5 aligned apertures 150 are the same as aperture 130 of FIG. 4, located near the aligned bag mouths 164, forming a aperture tab 151, which aperture and tab is mounted onto rod-shaped retaining hook 168. When mounted on retaining hook 168, the downwardly positioned flaps 158 are forced to turn up, thereby spacing the forward-most bag wall 160 away from retaining hook 168. Thus, as similarly illustrated in FIG. 2, the forward-facing wall surfaces do not come into direct contact with retaining hook 168 and will dispense much like that of the non-binding apertures of FIGS. 1, 2 and 3. Regardless of using flanges or flaps, the principle illustrated herein is to cause non-binding contact with a retaining hook, thus alleviating the need for a strong self-opening bond, and assisting to propagate a tear at a pre-weakened point.

[0025] In FIG. 6 aperture 170 is a single vertical slit with a top point 172, which ends just shy of the bag mouth 174, which bag mouth forms a top aperture portion 176. This particular aperture 170 is also a pre-weakened slit, since the top end 172 is located near to bag mouth edge 174, allowing for easy serverability.

[0026] In FIG. 7, aligned apertures 180 are single vertical slits like those of FIG. 6 and are part of a bag pack (illustrated only at the top aperture portion 186) that is mounted onto a horizontally positioned hook 188, which is shown in part by dotted lines in order to illustrate the inventive matter more clearly. When the single vertical slits of the aligned apertures 180 are mounted on retaining hook 188, the retaining hook causes the left side edges 192 and the right side edges 194 to turn outwards so that the forward-facing surface 196 of the forward-most bag 200 in the bag pack does not come into contact with retaining hook 188. Instead, the inner edges 193 and 195 of aligned apertures 180, or perhaps even the rear facing walls (not shown) are forced to press up against hook 188. Thus, when the forward-most bag 200 is dispensed from retaining hook 188 the aperture tab 186 will not bind on the retaining hook 188, allowing for self-open dispensing as described in the previous figures.

[0027] In all the above drawings, the same principle is taught, which is that of causing an aperture's edge(s) to turn away from a retaining hook so that the forward facing surface of a bag wall does not bind against the retaining hook.

[0028] From the foregoing descriptions and the many applications of using non-binding apertures, it will be appreciated that there may be variations on this theme, which would fall under the scope of the inventive matter. It is also not the intention of the present invention to be limited solely to the film products illustrated herein, such as T-shirt bags or merchandise bags, but may be used in whatever conceivable manner to improve the dispensing of any kind of plastic bag, pouch or envelope-like product.

Claims

1. A tab for mounting a bag bundle on an upwardly bent hook, the tab mounting comprising:

a bundle of bags having at least a leading bag and a plurality of trailing bags with each bag of the bundle of bags having;

a front bag wall having a top, a bottom, and two parallel side edges;

a rear bag wall having a top, a bottom, and two parallel side edges;

two bag sides, each bag side joining one of the side edges of the front bag wall to one of the side edges of the rear bag wall to form a closed continuum around the front bag wall and the rear bag wall;

a bottom joining the bottom of the front bag wall and the bottom of the rear bag wall to form a closed bottom to the closed continuum of the bag;

at least one tab attached to one bag wall of each bag in alignment with like tabs from like bag walls, the tab including:

a flanged aperture including at least one peak;

the at least one peak protruding inwardly toward and to the aperture for contact with the upwardly bent hook whereby the tabs of leading bags are bent out of alignment with the upwardly shaped hook at the dispensing end of the upwardly bent hook.

2. The tab for mounting a bag bundle on a retaining hook according to claim 1 including a slit partially severing the tab overlying the triangular shaped aperture.

3. A bag bundle on and dispensing hook combination comprising:

an upwardly bent hook,

a bundle of bags having at least a leading bag and a plurality of trailing bags with each bag of the bundle of bags having;

a front bag wall having a top, a bottom, and two parallel side edges;

a rear bag wall having a top, a bottom, and two parallel side edges;

two bag sides, each bag side joining one of the side edges of the front bag wall to one of the side edges of the rear bag wall to form a closed continuum around the front bag wall and the rear bag wall;

a bottom joining the bottom of the front bag wall and the bottom of the rear bag wall to form a closed bottom to the closed continuum of the bag;

at least one tab attached to one bag wall of each bag in alignment with like tabs from like bag walls, the tab including:

a flanged aperture including at least one peak;

the at least one peak protruding inwardly toward and to the aperture for contact with the upwardly bent hook whereby the tabs of leading bags are bent out of alignment with the upwardly shaped hook at the dispensing end of the upwardly bent hook.

4. The bag bundle on and dispensing hook combination according to claim 3 including a slit partially severing the tab overlying the triangular shaped aperture.