AU3220093A

AU3220093A - Inflatable package

Info

Publication number: AU3220093A
Application number: AU32200/93A
Authority: AU
Inventors: Geoffrey Boyer
Original assignee: Individual
Current assignee: Individual
Priority date: 1991-07-05
Filing date: 1992-06-30
Publication date: 1993-02-11
Also published as: JPH07503215A; WO1993001107A1; CA2046418A1; EP0592514A1

Description

INFLATABLE PACKAGE TECHNICAL FIELD

The present invention relates to an inflatable package and more particularly to a self-sealing, fluid inflatable package for use as a hot/cold pack or for the packing of fragile objects for shipment. The invention further relates to a one-way multiple valve construction having self-sealing properties. BACKGROUND ART

In the food industry, keeping food fresh during shipment often reguires that it be kept on ice. Single chamber plastic sacks, filled with water and then frozen, are often used during shipping. These sacks are typically of a single size and shape and thus are of limited adaptability to varying storage and shipping demands. Accordingly, it is clear that an ice pack that is more readily adaptable to differing demands would be an attractive feature for users of these devices in keeping objects cold during shipment. Similar considerations apply in relation to domestic users of ice/hot packs in coolers or other temporary storage media.

Furthermore, when shipping fragile objects, keeping the object well cushioned is important to limit damage due to impact or vibration. Currently, styrofoam "chips¹¹, injected styrofoam mouldings, "bubble" mats, popcorn and other energy absorptive materials are used to cushion fragile objects for shipment. Styrofoam mouldings are limiting as such cushioning can only be reused for objects of the exact original shape and size. Styrofoam "chips", popcorn and other packing particulates are messy and may settle during transportation, thus offering no cushioning effect to the object. Popcorn may attract insects and other vermin. Bubble mats when wrapped around an object do not securely hold that object without the aid of tape or some other binding. All the above-described packaging materials are themselves voluminous to both ship and store, and all create waste disposal problems with attendant problems of environmental degradation. Accordingly, it is clear that a device is needed that is self-adapting to the size and shape of the object being packed, will not settle during shipment, that will by its very nature secure itself around the object, that is itself easy to ship and store, is readily reusable or at least easily disposable and of course is cost competitive with existing systems. DISCLOSURE OF THE INVENTION

It is an object of the present invention to obviate and mitigate from the disadvantages associated with known ice packs and packaging media and provide an effective and easy to use device. In one broad aspect, the present invention relates to a plastic self-sealing package that can be easily filled with either air or liquid to function as either a hot/cold pack or as a packing medium. In another broad aspect, the present invention relates to a one-way self-sealing valve that operates between the package and the exterior environment as well as between a continuous row of interconnected chambers. In a further broad aspect, the present invention relates to a process for manufacturing the self-sealing package and the various other related embodiments of this invention. These various forms allow for the sack to be produced for the least possible cost per linear foot while still maintaining adequate structural integrity to the complete system.

According to the present invention, there is provided an inflatable package comprising outer deformable walls defining at least one fluid-tight chamber therebetween, valve means disposed within said chamber, and in fluid communication therewith, said valve means permitting the ingress of fluid into said chamber, and preventing the egress of said fluid therefrom, said valve means including a primary duct and at least one flow channel intersecting said primary duct at an angle to place said primary duct in fluid communication with the interior of said chamber. BRIEF DESCRIPTION OF DRAWINGS

Preferred embodiments of the present invention will now be described in greater detail and will be better understood when read in conjunction with the following drawings in which:

Figure 1 is a perspective view of a multiple chamber inflatable package in accordance with the invention; Figure 2 is a side elevational view of a one-way multiple valve assembly forming part of the package of Figure 1;

Figure 3 is a perspective, partially sectional view of the valve of Figure 2 in an internally pressurized condition;

Figure 4 is a perspective, partially sectional view of a modification to the valve of Figure 3;

Figure 5 is a perspective view of a further modification to the valve of Figure 2; and Figure 6 is an elevational view of a further modification to the valve of Figure 2. BEST MODE FOR CARRYING OUT THE INVENTION

With reference to Figures l and 2, the present inflatable package 1 comprises two major components, namely a deformable enclosure defined by outer walls 10 and a multiple one-way valve assembly 25 which permits the ingress of fluid into discreet pouches or chambers formed between walls 10 and which also acts to prevent the egress of that fluid once the chambers are inflated to the degree required.

Walls 10 may consist of opposed, typically rectangular layers of pliable plastic film 11 heat sealed or glued at their peripheral edges 9 to form a strong fluid-tight bond therebetween. The walls are similarly bonded together at seams 12 to sub-divide the package into discreet fluid- tight chambers or pouches 13, each aligned orthogonally to the longitudinal axis of the package. In the alternative, films 11 may be printed with release varnish in the areas representing chambers 13 so that the films can simply be fed between opposed heat rollers to cause the sealing together of only the unvarnished areas of the films.

It will be appreciated that walls 10 need not necessarily be rectangular in shape, and the chambers themselves may assume other geometric configurations. Prior to the heat sealing of the walls, valve assembly 25 is placed between the opposed layers of film 11. As shown in Figures 3 and 4, valve 25 consists of two opposed strips of pliable plastic film 26 and 27 sealed together along upper peripheral edge 28 and internally as indicated by lines 30 to define an infinitely repeated inverted U- shaped pattern. The seals, which are fluid-tight, define a continuous longitudinally extending primary fluid duct or main artery 32 and a series of parallel, spaced apart, transversely extending flow channels 33, each of which is in fluid communication at its upstream end 34 with primary fluid duct 32 and at its downstream end 35 with the interior of a respective one of chambers 13. In one embodiment constructed by the applicant, channels 33 intersect duct 32 at a 90° angle. Webs 37 formed between adjacent flow channels 33 are sealed along each of their adjoining edges with flow channels 32 and 33. Advantageously, the webs are also sealed along their lower edges 39 to prevent the ingress of fluid between strips 26 and 27 and are additionally reinforced by an "X" shaped seal 41 made therein. Sealing of the valve in the manner described above is easily accomplished by an impulse die which descends onto films 26 and 27 to apply enough heat to the edges and seams in question to permanently seal the two films together to form the pattern of ducts as described hereinabove. In the alternative, strips 26 and 27 may be printed with release varnish and heat rollered to form the required end product. Although strips 26 and 27 may comprise a single sheet of material folded over onto itself with upper edge 28 defining the fold line, a more reliably fluid-tight seal has been found to be formed if strips 26 or 27 are sufficiently wide to provide an overhang 43 (Figure 4) at least at the upper but preferably at both the upper and lower edges of the valve. Advantageously as well, the rounding of the seams at the intersections of ducts 32 and 33 as shown most clearly in Figure 4 appears to reduce material fatigue when the valve is under pressure.

After valve 25 has been interlayered between films 11, the heat sealing together of the outer walls 10 can take place. A release varnish applied internally in a continuous band 51 to strips 26 and 27 within primary fluid duct 32 prevents the inadvertent sealing of duct 32 at its points of intersection 54 with seams 12. The varnish can be applied of course only to those parts of the duct intersecting with seams 12, but this would require that the valve be properly aligned with the seams prior to the application of heat.

With reference to Figure 6, there is shown a further slightly modified embodiment wherein like elements are identified by like reference numerals. As will be seen, ducts 32 and 33 and webs 37 are surrounded by a pattern of thickened seals 82 with the downstream ends of ducts 33 extending beyond (or below) the seals closing off the lower ends of the webs. In use, fluid introduced under pressure at an upstream end 70 of primary duct 32 "inflates" the duct as the fluid travels downstream in the direction of Arrow A towards the next adjacent seam 12. Although the release varnish has prevented duct 32 from being sealed completely closed at the intersection 54, nevertheless, it requires a pressure buildup to "pop" the intersection and before this occurs, the fluid will enter flow channels 33 as indicated by Arrow B, flowing therethrough into chamber 13 as indicated by Arrow C. The fluid will then completely fill chamber 13 until the pressure buildup in the chamber and the pressure required to pop the seal at intersection 34 equalizes. When this occurs, the intersection will pop and fluid will flow downstream into the next adjacent chamber via duct 32 and channels 33 opening thereinto. This continues until as many chambers as are needed or required are filled. The filled portion of the package may then be detached along perforated lines 65 formed in seams 12 for this purpose. Alternatively, a cut using scissors or a sharpened edge can be made along the seam.

Intersections that "pop" under pressure may be undesirable in the event that the pressure required to cause the pop could exceed the burst strength of films 11 or strips 26 and 27 or the seams made therein. Accordingly, in an alternate embodiment, additional release varnish or other seal preventing media is applied to the internal surfaces of duct 32 to prevent or at least minimize any closure of the duct at intersections 54. Fluid introduced at upstream end 70 will then travel the length of duct 32 without significant restriction. To accomplish the filling of the chambers, the intersection 54 immediately downstream of the last chamber to be filled is pinched off or held closed either manually or automatically by an apparatus (not shown) dispensing the uninflated packaging from a roll thereof. Typically, the last chamber will be the first to fill with successive upstream chambers filling in order thereafter.

Depending upon the width of chamber 13, one or more ducts 33 may open thereinto. When the supply of pressurized fluid is removed, the pressure in ducts 32 and 33 drops to atmospheric. This causes the ducts to physically collapse into a substantially flat condition under the pressure of the fluid in chambers 13 so that the walls of the ducts are actually compressed together in a suffocation effect to prevent the egress of fluid from the chambers. There will be a small amount of fluid leakage representing the fluid in the ducts at the moment of their collapse, but beyond this, the chambers will be sealed in a substantially fluid- tight condition.

With reference to Figure 5, there is shown a modification in which valve 25 is formed by sealing a single strip of plastic film 60 directly to the inner surface of one of films 11. In other respects, this embodiment is the same as that described above with reference to Figures 1 to 4. This construction not only reduces the amount of plastic film needed to construct the valve, but results in a significant reduction in the stress to which the valve is subject when under inflation.

In one embodiment constructed by the applicant, the material used for valve 25 is low slip (i.e. high coefficient of friction) 1.5 mil polyethylene/EVA or EVOH film which increases the suffocation effect for one-way fluid flow when ducts 32 and 33 collapse under pressure of the fluid in chambers 13. Outer skin 10 may also be a polyethylene film or nylon polyethylene laminated film or tri-extruded polyethylene nylon polyethylene film or polyurethane film of varying thicknesses depending upon anticipated loads. A tri-extrud^d film of LDPE/HDPE/EVA resin may also be used in view c this material's high tensile strength, minimal tear propagation and reasonable cost relative to competitive plastic film products presently on the market. It is anticipated that the present package will be manufactured in strips of, for example, 450 linear feet for winding onto rolls. Chamber widths will vary from a minimum of a fraction of an inch on up. Product height may again vary in a wide range from a few inches to a few feet or more. Outer walls 10 may be clear or opaque and may be printable for logos, trade-marks and the like.

Chambers 13 can be filled with air for packing or insulating purposes. Water can be used for freezing the package into ice packs.

Other fluids than can be used include commercially available gels useful for either cooling or heating purposes. As many chambers as are needed can be torn off to form a pack as large or as small as may be required. The package can be reused or disposed of when done with.

For packaging purposes, a strip made into a closed loop if desired can be used for wrapping a television, computer or a similarly fragile commodity and then inflated, or inflated prior to packing. This will at once conform the shape of the strip to the merchandise being wrapped and will cause the package to constrictively engage the merchandise to prevent slipping. Linear strips can be used for stuffing between the package walls and the enclosed goods. Pouches or pockets can be formed for enclosing smaller goods. The packing will not of course settle and even if the odd chamber is punctured, this will not result in leakage from adjoining chambers and product integrity will be substantially maintained.

Claims

CLAIMS :

1. An inflatable package comprising: outer deformable walls defining at least one fluid- tight chamber therebetween; valve means disposed within said chamber, and in fluid communication therewith, said valve means permitting the ingress of fluid into said chamber, and preventing the egress of said fluid therefrom, said valve means including a primary duct and at least one flow channel intersecting said primary duct at an angle to place said primary duct in fluid communication with the interior of said chamber.

2. The inflatable package of claim 1 wherein said deformable walls comprise opposed layers of pliable film sealed together adjacent the peripheral edges thereof in fluid-tight relationship.

3. The inflatable package of claim 2 wherein said deformable walls are additionally sealed together at spaced apart locations at seams sub-dividing said package into a plurality of said fluid-tight chambers.

4. The inflatable package of claim 3 wherein said valve means comprise opposed strips of pliable film sealed together to define therebetween said primary duct extending the length of said strips and said flow channels intersecting said primary duct at an angle, said flow channels being in fluid communication with said primary duct.

5. The inflatable package of claim 3 wherein said opposed strips of pliable film comprising said valve means are sufficiently wide to form an overhang along the longitudinal edges of said strips.

6. The inflatable package of claim 4 wherein said flow channels intersect said primary duct at an angle of 90°.

7. The inflatable package of claim 4 wherein at least one flow channel is formed in said valve means for each of said chambers formed in said package.

8. The inflatable package of claim 4 wherein said primary duct includes means therein to prevent the permanent closure thereof at points where said primary duct intersects with said seams sub-dividing said deformable* walls into said chambers.

9. The inflatable package of claim 8 wherein said means comprise release varnish coating inner surfaces of said primary duct at least where said primary duct intersects with said seams.

10. The inflatable package of claim 9 wherein said primary duct, said flow channels and said chambers are inflatable by means of the injection of a pressurized fluid.

11. The inflatable package of claim 10 wherein said primary duct and said flow channels are collapsible into a substantially flat condition to prevent the egress of fluid from said chambers when the injection of said pressurized fluid terminates.

12. The inflatable package of claim 11 wherein said inflatable package is substantially flat when non-inflated.

13. The inflatable package of claim 12 wherein said pliable film is polyethylene sheeting.

14. The inflatable package of claims 1, 2 or 13 wherein said primary duct and said flow channels are formed between a strip of said pliable film sealed directly to the inner surface of one of said deformable walls.