This invention relates generally to a packaging system and more particularly to a package comprising an outer bag having an article-carrying inner bag suspended therein.
U.S. Patent No. 4,597,244, issued on July 1, 1986 to Daniel A. Pharo for "Method for Forming an Inflated Wrapping", discloses a packaging system and method wherein an article is packaged within an inflated, sealed bag. The present invention provides certain improvements and variations over the packaging system and method taught in the above patent.
U.S. Patent No. 4 155 453 discloses a packaging structure comprising an envelope comprising a plurality of flexible interleaved wall panels, an outer pair of said wall panels being sealed together to form a first open-ended enclosure and an inner pair of said wall panels being sealed together to form a second open-ended enclosure defining an item-receiving zone therein, said inner pair of wall panels being sealed to and between said outer pair of wall panels so that said second open-ended enclosure is disposed within said first open-ended enclosure, wherein the only means of ingress to or egress from said item receiving zone is by the open end of said second open-ended enclosure, and the seal joining said inner pair of wall panels is so located and configured as to define a sealed inflatable chamber above said second open-ended enclosure, and a sealed inflatable chamber below said second open-ended enclosure, both of the inflatable chambers being inflated by intake valve means.
The chambers are independently sealed, and this makes it difficult to provide even protection for an item in the item zone.
According to one aspect of the invention there is provided a packaging structure as defined in claim 1.
According to another aspect of the invention there is provided a method for packaging an article as defined in claim 9, this packaging method being particularly adapted to the above-mentioned packaging structure.
Preferred embodiments of the invention are specified in the dependent claims.
Advantages of this invention will become apparent from the following description of an exemplary embodiment shown in the accompanying drawings, wherein :
Figures 1 and 2 illustrate a packaging system 20 comprising an outer bag 21 defining an inflatable, sealed chamber 22 therein. An inner bag, defining a pocket 24 for retaining an article A therein, is disposed within split chamber 22 and has peripheral edges thereof secured to the outer bag, in a manner hereinafter fully described, to support and suspend the inner bag within the chamber. As illustrated in Figure 3, outer bag 21 comprises a pair of superimposed and identical panels 25 and 26 whereas inner bag 23 comprises a pair of superimposed panels 27 and 28 connected together at a fold 29.
Each panel 25-28 is preferably composed of a gas-impervious composite laminate, such as the type described in U.S. Patent No. 4,597,244. For example, each flexible panel may comprise an intermediate layer of aluminum and outer and inner layers of a plastic heat-sealable coating, such as polyethylene, adapted to reactivate (melt) in the range of 150°C (300°F). These types of composite laminates (which may be constructed to be highly flexible and inextensible or extensible) are well known in the art and, therefore, further description thereof is unnecessary for a full understanding of this invention. In the embodiment illustrated, the panels of Figure 3 are heat-sealed together at selected overlying peripheral edges thereof to preform a package for the packaging system with a closeable end closure 30, illustrated in its open condition in Figure 4.
Figure 3 illustrates overlying common sealing areas peripheral edge portions of the panels by dot-dash lines 31 for explanation and clarification purposes. The panels may be suitably cut and sealed together by conventional apparatus and methods, such as those described in U.S. Patent No. 4,545,844. It should be noted in Figures 1-4 that stem portions 32 and 33, formed integrally with and extending outwardly from edges of panels 25 and 26, respectively, are heat-sealed together about their edges. These stem portions are further heat-sealed to underlying parallel side edges of panel portions 34 and 35 of panels 27 and 28, respectively, which are joined together at fold 29.
Fold 29 and the remaining portions of panel portions 34 and 35, extending transversely between the superimposed and sealed edges of panel portions 31-34, remain unsealed relative to stem portions 32 and 33. As shown in Figure 6, fold 29 extends a limited distance into a filling stem 36, defined by overlying and sealed stem portions 31 and 32. As described more fully hereinafter, a pair of inlets are thus formed at fold 29 to communicate a pressurized fluid, such as air, to split chamber 22 on either side of inner bag 23.
A method for packaging article A to form packaging system 20 and to suspend the article at a fixed position within chamber 22 of outer bag 21, as shown in Figure 2, will now be described with particular reference to Figures 4-7. After the package has been prefabricated to assume its open-ended envelope-like configuration illustrated in Figure 4, article A is inserted through the open end of inner bag 23 and into pocket 24. It should be understood that the article could be placed at any desired position within the inner bag and will be firmly held in such position when the packaging system is inflated or otherwise charged or filled with the preselected filler medium, as described hereinafter.
After the article has been placed within pocket 24 of inner bag 23, overlying edge portions of formerly open end 30 are heat-sealed together at a seam 37, as illustrated in Figure 5, to form an end closure. The sealing apparatus used for this purpose may be of the type described in U.S. Patent No. 4,597,244, such as the impulse table top bag sealer Model 210-8 manufactured by A. I. N. Plastics, Inc. of Mount Vernon, New York. Sealing of the open end of the package will thus fully seal pocket 24 of inner bag 23 and will also substantially seal chamber 22.
Inflating means for charging and at least substantially filling chamber 22 with a pressurized fluid is shown in the form of an opening uncovered by a tab 38 defined by a cut line formed only through stem portion 32. An inlet passage 39 to the chamber is defined within filling stem 36 (Figure 6). Alternatively, the inflating means for charging chamber 22 could comprise an inflation valve, such as the one disclosed in U.S. Patent No. 4,586,910 and illustrated at 40 in Figure 8.
After the open end of the package has been sealed at seam 37, a standard inflation apparatus, including a fill tube 41 (Figure 5), can be utilized to charge and pressurize split chamber 22 to an inflation pressure exceeding ambient pressure, e.g., exceeding 14.7 psi at sea level. Alternatively, human lung power could be utilized to inflate chamber 22 with air. Other types of gases, such as helium, could be utilized as the filler medium, as well as a suitable liquid, such as water. Alternatively or in addition to the pressurized fluid, the chamber could be filled with a plastic (e.g., urethane, polystyrene, etc.) material in solid (injected in liquid form and solidified) or pieces (e.g., balls or pellets) form.
After the package has been inflated to suspend inner bag 23 and article A at its preselected fixed position within chamber 22, fill tube 24 is removed. Tab 38 is simultaneously compressed into stem 36 to prevent the pressurized fluid from escaping. As shown in Figure 7, stem 36 is then quickly heat-sealed at a seam 42 (sealing only stem portions 32 and 33 together) and/or at a seam 42′ (sealing stem portions 32 and 33 and panel portions 34 and 35 together).
Referring to Figure 2, article A is thus substantially encapsulated by the filler medium and supported and held at a fixed position within chamber 22. Compressive forces occasioned by the pressurized fluid will be directed inwardly and uniformly against the exposed upper and lower surfaces of inner bag 23 to compress and conform the flexible wall panels of the inner bag to the contours of the article. Retention of the article in a fixed position within split chamber 22 is further aided by the horizontal components of forces acting on inner surface portions of transversely disposed side seams 43 and 43′ of outer bag 21.
The latter holding force desiderata is more clearly illustrated and pronounced in modified packaging system 20′ (Figures 8 and 9) wherein horizontal force components F will tend to place panels 27 and 28 of the inner bag in tension. In order to increase the horizontal force components F in this manner, outer bag panels 25 and 26 are prefabricated to have widths greater than the widths of panels 27 and 28 (Figure 8).
Figure 10 illustrates an alternative end closure for packaging system 22 that can be used in lieu of heat sealed seam 37 (Figure 1). In Figure 10, panels 25-28 are cut to different lengths to define relatively longitudinally staggered panel edges 25′-28′. A standard tape 44 is heat-sealed or mechanically secured over the ends of the panels to close and seal chamber 22 and pocket 24. Other types of end closures can be used such as a standard tape that is folded over the end of the package and then heat-sealed or mechanically sealed in a conventional manner thereover. The opposite ends of the tape are then folded inwardly towards each other and secured in place. Also, a standard tape can be secured to the outer side of panel 25 and a protective strip removed from the tape after article A (Figure 4) has been inserted into inner bag 23. The panels of the bags can then be folded on a preformed crease or fold line to secure the panels together. If so desired, the end edges of the panels can be staggered longitudinally in the manner described above in reference to Figure 10. The end closure can also be formed by press-fitting and clamping an elongated cylindrical rod within a separate and generally C-shaped retainer. The rod should be sufficiently elastic to be compressed into the cavity of the semi-rigid retainer and permitted to expand to firmly compress the panels of the end closure therebetween to seal and isolate chamber 22 and pocket 24 (Figure 2). Alternatively, the rod could be composed of a semi-rigid plastic material with the retainer also being composed of a plastic material, but exhibiting sufficient flexure to spread and permit the rod to snap-fit or press-fit within the retainer in a well known manner.
Various opening devices and constructions can be utilized and formed into the end closure to open packaging system 20. For example, a cord or thread can be implanted in the heat-sealed end closure to adapt it for removal by a consumer. As an alternative or in addition to the cord, a second cord can be likewise implanted adjacent to heat-sealed side seam 43 or 43'(Figure 1) to permit its removal and opening of the packaging system. The cords may be suitably secured within the underside of one of the panels forming inner pouch 23 whereby article A (Figure 2) will be exposed when the cord is removed.
Various other modifications can be made to the preformed package and completed packaging system of this invention without departing from the spirit and scope thereof. The package could include additional bags, secured to bags 23 and 25 in the manner described above. Instead of using distal end 30 of packaging system 20 as the open side thereof, this end of the system could be heat-sealed during prefabrication of the package and one of the lateral sides left open and utilized for packaging purposes in the manner described above.
The heat-sealed seams of the system could be formed in the manner described above, or the panels folded onto each other and then heat-sealed together to form a seam having eight plies, for example. Gusseted seams could also be employed with the corners of end closure being folded inwardly towards each other and heat-sealed in place. In addition to the above-described end closures, the end portions of the panels comprising the end closure could have encapsulated beads of glue formed thereon which would function to adhere and seal the panels together when pressure and/or heat is applied to the panels to rupture the beads of glue. These portions of the panels could also be multi-folded over each other and then heat-sealed or reverse folded onto each other and then heat-sealed.