CA1177031A - Inert gas balloon packaging system for corrodible products - Google Patents

Abstract

METHOD AND MEANS FOR
PROTECTIVELY PACKAGING ARTICLES

Abstract of the Disclosure Method and means for protectively encasing a product to resist rust, oxidation and corrosion thereof. The method entails the injection of an inert gas in a container to displace air therefrom and sealing of the container to retain said inert gas in the container. The casing means constitutes a flexible gas impervious container with an opening to admit insertion of a product and at least one opening to accommodate injection of an inert gas into the container and discharge of oxygen, said container being provided with means for sealing each opening.

Description

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ME'X'HOI) AND MEP~NS E'OR
P~OTECTIVF~Y PACK~GING ARTICIJES

5ummary of the Inven~ion This invention relates to method and mean3 ~or protectively packaging articles.
Many products and materials are subject to rust and degrading airborne particulate matter if not ef~ectively pro~ected, particularly in cases where the same ~re stored for medium to long-term periods. Examples of items for which prokection is desirable include such items as raw steel products~ ~inished products made of steel~
computers and ancillary equipment, high precision metal parts and equipment, small military equipment such as arms, artillery and vehicles, microprocessers and housings, motors and engines, high unit cost items stored for less than one year out of doors such as cars, trucks, tractors and boats, items which axe transpvrted or stored near salt water, furniture which is being .shipped or stored, and goods of various types which are shipped oversea~ and are subject to salt water atmosphere~. Pre~ently availahle methods and means to prokect ~uch material~ are o~ limited utility or are objectlonably expen~ive or otherw.i~e o~jectionable.
It is the primary object o~ this invention to provide a novel, simple and inexpen~ive method by which praducts and materials re~uiring protection from airborne conditions may be conditioned and protected to minimize deterioration thereof or damage there~o~
A further object is to p~ovide a method wherein a product or material to be protected is encased w.ithin a flexible houslng or container into the top or upper paxt of which is introduced an i.ne:rt gas immiscîblewith air ~7'7~3~l and of a ~reater spectfic gr~vit~ than air to ~isplace or discharga the air in the container, ~ollowing which the container i9 ef~ectively sealed~
A Eurthex object is to provide a flexible container of air imper~ious material which can be readily sealed, which is subject to negligible 108s of inert ga~ through khe osmotic process, and which is characterized by requisite gualities of strength, flammability~ burst strength and resistance-to-shear, into which an inert gas ~ay be introduced after the container receive~ the material to be protected, and which container may readily be sealed at its openings after inert gas is introduced to expel oxygen thererom.
A further object is to provide a container which can be sealed after contents are introduced therein and which is provided with a pressure-responsive check valve at its uppermost portion to permit dischaxge o~ air and with a sealable filling openincJ for introduction o~ inert ~as in a quantity suf~icient to displace and dlscharye thxollgh the check valve outlet the air displacecl by the lnert gas.
Other objects will be appaxenk fxom the following 5peci fication.
Brie~ Descri~tion_o~ ~he Drawin~s Fig. 1 is a perspective view of one embodiment of the invention adapted to anclose and protect a machine or vehicle.
Fig. 2 is a perspective view of the container illustrated in Fig. 1 whil~ empty.
Fig. 3 is a fragmentary ~iew of the container of Fig.
at the portion adjacent the opening thereo~.
Fig. 4 is a fragmentary view illu~tl~ating a ~tep in the sealing of the opening o~ the container illu3trated

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in Fi~. 2.
Fig. 5 i9 a fragmc-ntary view illustrating an in~er-mediate step in the sealing o~ the opening of the container illustrated in Fig. 2.
Fig. ~ is an and view of the container o~ Fig. 2 which has been sealed.
Fig 7 is an enlarged end view of the sealed container portion illustrated in Fig. 6.
Fig. 8 is a plan view of another embodiment of the container.
Fig. 9 is a sectional view taken on line 9~9 of Fig. 8.
Fig. lO is a plan view o another embodiment of the invention.
Fig. ll is a plan view of still a~other embodiment of the invention.
Fig. 12 is a sectional view taken on line 12-L2 of Fig. lO.
Description of the Pre~erxed ~di~
Referring to the drawings which illustrate one embodiment of the invention, and particu.larly to ~i.g~. 1~7, inclusive, which illustrate one en~odiment o~ the i.nv~ntion deslgned or intended for use to enclose machinery, ~uch as a vehicLe or other large article, the numeral 22 designates the container. Container 22 may be a sack or bag having a filling mouth 24 of a size to receive the vehicle or other item or material to he protected. The container 22 may be formed of polyethylene 6uch as ~ *, rubberized or synthetic rubberized materials, or any flexible sheet material which i9 impervious to aix, which can be readily ~ealed, which is capable o~ retaining an inert yas with minimum loss through osmotic action, and

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which has pxoperties o~ strength, 1ammability, bur~t stxength and resistance-to-shear suflcient to e~ectiv~ly protect contents o the contain~r while beiny ~tored, transported, or shipped. One material ~or the intended u3e is polyethylene film of a thickness from one mil to ten mils. Polyethylene is not essential and other flexible materials may be available which have the followin~ general properties and charac~eristics:
(a~ an effective temperature range or material and use conditions between -60F to +180F;
(b) tensile strength (p~i) of between 1,500 and 3,000 per ~quare inch (ASTM);
(c) tear strength of hakween 50 and 300 pounds (ASTM);
and a smoldering or flammability rate of 19.5 inches per minute (ASTM). The containex matexial may exceed the foxeyoing values. The material should maint~in îts integrity under an internal pressure load of up to 10 pound~ ~psi).
The container can be of any ~ize, assumin~ that it is capable of beiny fill~d with inert gas and to b~ ~ealed approximately airtight~ The container can elth~x ~tand alone, that is, can a~sume a ~hape ~tlpported by the contents and not re~uiring external supporting ~kructure, or may be placed inside another container, box or ~ag, or upon a pallet, for protection again~t de~tructive or damaging contact with adjacent items ox structure~. In the event the container is intended for use within another container such as a box, it is preferable that the in~tarlt container b~
independent of, i.e., not attached permanently to the ou~ide protective container.
The container of ~ig~ 7 i~ provided with a sealable~
gas charging nozzle, neck or inlet 26 and with one or more gas outlets 28 pref~rably of the check va~ve type which

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permit expulsion o gas from the Lnt~rior o~ the container and prevent entry of gas or air therethrough from th~ ex-terior of the container. The inlet 2& and outlet 2~ are pre~erably so located that they are uppermost in the normal use position of the container when filled.
Suitable means for sealing the filling mouth 24 ara provided. One such means is illustrated herein as a rigid bar, stud or okher member 30, o~ a length greater than the width of the container, which can be placed across the container adjacent the mouth thereof as illustrated in E'ig. 4. It will be understood that the folding of the container at the corners along fold lines 3~ as illustrated in Fig. 3 to provide end folded flap members 34 shown in Fig. 4 is optional. The portion of the contain2r adjacent the mouth 24 is then progresslvely rollêd or coiled tightly around the dowel or other member 30 to produce a number of convolutions around member 30 sufficient to provide a multiple thicknes~ cncirclement o~ the member 30~ In instarlces where ~laps 34 are fold d as illustrated in Eliy. 4, the number o~ convolution~ 3&
will be suf~icient to provide exten~ion or po~itionlng o~ the rod heyond th~ innermost ~dyes o~ the erld ~olded flaps 34. A ~econd rigid rod 38 i~ then placed again~t thQ
coiled or convoluted container material 36 in a position parallel to the rod or dowel 30, and suitable means 40 are utilized to connect the expo~ed ends of the dowels 30 and 38 in a manner to compact and compress the coiled or convoluteA material therebetween as illustrated in Fig~ 7 and thereby insure against entxy of air from th~ atn~phere bctween the convolutions 36 and into the cont~iner.
The container illustrated in Figs. 1-7 is u~ed by introduciny therein through the filling mouth 24 thereof, -- 5 ~

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the machin~ or other axticl~ to bc houscd therein whil~
the gas inlet 26 and outlet 2~ are positioned a~ uppPr-most locations of the loaded container. The container contents are so located that the portion o~ the container adjacent the filling mouth 24 thereo is .fxee t~ permit it to be rolled or coiled around a dowel or rod 30 followed by application of the second rigid rod 38 and the securing means 40 in the manner described above.
Alternatively, any other sui~able means to seal the container adjacent to its mouth 24 may be provided, such as a heat seal across the container adjacent the ~illing mouth or a seal provided by cement, glue or a solvent.
A~ter the container 22 has been filled and sealed, argon, an industrial gas having 80%~ of argon and 20D/o~
of nitrogen, or any other inert gas which is not mi~cible Wit}l air is introduced through the charging inlet 26 in sufficient quantity and until such kime as substantially all air is displaced thereby and discharged from the container throu~h the gas outlets ~8. Injection o~ lnert gas may be terminated when discharge o~ air through ~uch outlets ceasqs as determine~ by discharge o~ the charglng inert gas only at the outlet~. The argon or ot~ler charging gas, being o~ greater speci~ic gravity than the air, falls to the bottom o~ the container and p~ogressively displaces and shifts air upwardly in the container for discharge at the outlets 28.
~ hen the container of Fiy. 1 has been charged with argon or other inert immiscible gas, the content~ o the container are e~e~tively protected agains~ ru~t, corro~io~
and airborne particulate material. Thi~ protection is provided as long as the container i~ s~aled and i~
effective for long period~ of time, such as man~ months, ~'7~7~3~

for e~ample, from fall to spxlny ~or agricult~tr~l lmplem~nts, boat~ and the liXe.
When the contained protected ob~ect i~ to be usedr the securing means 40 can be released, the outer dowel or xod 38 removed, and the portion of the container around the filling mouth unwound from the rod 30, so that the container contents are available for release thxough the fill.ing opening 24. The container can then be folded for ~to.rage and later xeused.
In instances in which a heat seal line, or cement, glue, or a bonding agent ha~ been appliad across the container near the filling opening 24, the container can be opened by severing it inwaxdly of the seal line so as to open the container, and remove the contents.
The container so opened, while slightly reduced in 5i2e, is readily available for reuse.
Fi~. 8 illustrates a modi~ed embodiment of the invention where:in a container o~ pol~ethylene or other flexible sheet materlal o the ch~xacter de~cxihed abo~e i.s formed to provide an upper wall 50 and a lower wall 52.
The margin~ o the walls 50 and 52 a~e bonded together at opposite longitudinal seal lines 5~, such a~ heat seal lines or cement or bond lines, and a connected transverse seal line 56 at one end thereof. At the opposite end the upper and lower walls are joined at converging seal lines 58 and ~0, which ext nd from the filling mouths 62a, 62b lengthwise to a point intermediate the length of the container at which the seal line~ 58 and 60 meet. By this arrangement a .relatively largs filler mouth portion 62a is provided at one end of the container and a relatively small fillirlg opening 62b i~

provided spaced from the opening 62a.

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Th~ container o~ ~ig. 8 i~ particulaxly u~ul forthe stoxaye of small arkicles and particulate and fluent material and liquida. The ~illing o~ the d~ired contents i~ accompli~h~d through the opening 62a, following which a seal line 64 is ~ormed to close the mouth portion 62a~
The container is then positioned with the mouth portion 62b uppermost, ~ d argon or othex heavy inert gas is introduced under pressure through mouth 62b to displace the air in the container and diqcharge it through mouth 52b.
After the air has been discharged from the container, a seal line 66 may be provided to clo~e the ga~ iller mouth 62b and thus effectively seal the container and pxotect the contents. A container oE this character may be opened by severing it trans~ersely, as along the line 68.
The containex may then be emptied and is ready ~or reu~e, though in slig~tly smaller size. Following filling of the reduced size container it can be resealed along seal lines 70 and 72. Successive reu~e~ can continue, with progressive slight reduction~ in the size of the containor, until the overall length of the container i~ reduce~ to a dimension slightly greatex ~han the dimension between the transverse seal line 56 and the point of juncture of the seal lines 58 and 60.
Anothèr embodiment of the invention i~ illu~trated in Fi~. lO, which is formed of polyethylene ~heet material and is constructed substantially the same a~ the container shown in Fig. ~3, with the exception that only a single longitudinal ~eal line ~O'extends from the open mouth 62 of the bag. In this embodiment, the s~al line 60'may extend at an anyle as shown in ~ig. lO or may be substantially parallel to and spaced from the seal lines $4. U~age of this bag is substantially the ~ame as the usac~e described ~L ~L)7r7 ~ 3~

in reference to the Fig. 8 corlstruc~ion~
Another embodiment o.~ the invention i~ illustrated in Figs. lL and 12 wherein ~ bag is form~d o.~ polyot,hylene sheet material and has an upper wall ~0, and a lower wali 82. A longitudinal seal line 84 extends along one longitudinal margin to bond the upp~r and lower walls and a pair of transverse end ~eal lines 86 and a plurality of intermediate spaced pairs of tran~verse seal lines 88 e~tend across the container. The container is thus divided into a plurality of sections each saaled at three sides and each open along one longitudinal margin of the container at gO.
In use, the container illustrated in Fig. 11 is filled at the respective sections or compartments thereof and then is sealed partially acro~s the each open mouth 90 leaving a small opening through which a noæzle of a ya~
discharge member can be inserted and through which air can escape as heavy inert gas is introduced into the container while the remaining open mouth portion 90 i9 at the uppermost position. The remaining open portion~ o~ the mouth~ ~0 o~ the containers can ~hen be sealed, thus pxovlcling a plurality o small connected ~eal~cl containffrs, e~ch of which is filled with the contents to be protected and with an inert gas. It will be apparent that the various sections or compartments of the FigO ll container ~ay contain predetermined quantities of material to ba protected and that each section may be opened as required. T~u~ when the contents of one o the sections or compartments is required, that section may be se~ered from the rema~ning sections along a line between the dual seal lines 88.
Then the severed or ~eparatecl section can be opene~ for discharge o its content~ while protection of the remaining ~77~3~

contents in the other sec~ion~ to air con~inue~, Each of the en~odiments illustrated and dcsc~ib~d above i5 usable in applioant's primary method wherein argon o.r other inert ga~, not mixable wi.th air, ls introduced throu~h an opening located in the upper portion of the containex so as to fall to the lower portion of the container and replace the air content therein, forcing the air out of the container. When the inert gas completely fill5 the vo'ds within the container, the conkainer can be sealed. The content~ are thus protected in an air-free environment against deterioration or the occurrence of oxidation of metals or damage of contents by dust, dirt or other airborne material ox particles and ~rom a salt water atmosphere. The container employed must be air impervious. Preferably the container is flexible so that its filling opening and air exhaust openings can be uppermost during gas charging and sealing operations~ The container is ~ormed of material having adequate strength, shear resistance, and flam0 resistance, during usage.
The container material must be capable o~ sustaining a predetermined wide xange o~ prQssure and must have ade~uate tensile strength and tear and .~larne res.istance ~or the intended usage. The inert ga~ pressure within the conkainer when illed and sealed wlll normally not exceed 2 psi~ but may be of any value which the contalner will receive and maintain and preferably not substantially greater than 10 psi.
The container can be o~ any size, a~suming that ik can be ~illed with the desired contents, then filled with inert gas and then sealed airtight. The container can either stand alone or it can be placed within another container, swch as a box, or it can be placed UpOll a ~L~Lr~ 7~31 pallet to protect it ~rom surroundlng objects q'he container may consist of one or more air pervious inner bags containiny the product to be prote~ted which a~e plaa~d within an air imperv.ious outer container so that ~illing of the outer bag with inert gas may occux with re~ultant displacement of air from each inner bag priox to sealing of the outer bag. The protective flexible bags will preferably be larger than required to receive the desired contents so that, after a seal is broken, the unit may be emptied and re-used by refilling and resealing the same.
The bags are o suitable strength so that they not only contain and protect the desired contents, but are strong enough to permit transportation of the contained products while maintaining protection against degradation, rusting, and other injury ~rom external sources.
The methods util~zed may vary wi~hin a wide range.
One simple method is to place the objec~ to be protected in the polyethylene or othex suitable containex, seal the major portion of the container ~illing mouth, introduce inert gas at pressures between 50 to 200 psi, as through a nozzlP inserted through an opening at the top o~ the container, to displace air ~rom the container untiL the container is fully filled with the inert ga~, ~ollowing which the ~upply of the inert ga~s is terminated and all bag openings are closed ox sealed.
Another method entails the same step~ but utilize~
a container having a check valve at the air outlet and a sealable inlet as descri~ed in connection with the container shown in Figs. 1~7.
Another method constituting a variation of either of the two aforementioned methods entails loadlng the polyethylene or other container with the material to be 7'7~

preserved, ~hen reducing the atmospheric pressure within the container by connect~on thereo~ to a vacuum source, then introducing axgon o.r other inert ~a~ to fill the bag, and then sealing the bag after it is filled with aryon.
In this method an additional tep may be used, namely, subjecting the ~illed container to vibration incident to insertion of the gas so as to insure against trapping o~
air in pockets within the container.
Another method particularly use~ul wherein a product 10 is to be preserved on a short term basis may utilize a flexible unsealed bag of polyethylene or other air impervious material which is placed within a preformed rigid container alongside a worker. Such a ~ag containing material to be protected is filled with inert gas to a level which covers the material but does not flow out over the upper edge o~
the rigid contalner. The flexible air imperviou~ container is then folded upon itself at its uppermost portion to retain the inert gas. In the usage of such a bag the worker may reach into the bag at the folded part thereo to remove an article,~ollowing which he again ~old~ the container to insure again~t protectiv~ gas discharge or outflow. In this method argon, in small quantiti.es, may be constantly or intexmittently supplied into the container.
In another method, any of the foxegoing methods may be employed in a unit having two bags, one within another~
wherein the inner bag is filled with the material to be protected, is then charged with inert gas, and is then sealed. The outer container is then charged with the inert gas and ~ealed. By this mathod the content~ within the inner bag are given greater protection from taaring, temperature change, contact damage, and humidity chAnges than is provided by a single bag.

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Various sealing techniques can be used, depending upon the needs and preEerences of the user. The sealing technique utilized may be determined by the 1exible container makerial~ by the product contained within the conta.inex, by production techni~ues or by transpoxtation modes or other factors. Regardless of the sealing technique employed, sealing is adequate if the container, as loaded, is airtight, and the product contained is completely enclosed.
In addition to bags of the types discussed above, it will be understood that other types of bags may be used in different circumstances. One such type is known as a plasma bag, usually formed at least in part of polyethylene and prefitted with an input nozzle and a check valve outlet. Other types of contai.ners which can be used can be of the so called pneumatic types, usually containin~ air under pressure, or medical sterile vials which are provided wikh rubber stoppers and from which contents may be withdrawn by means o~ a hollow needle associated with a withdrawal receptacle of ~uction means having a shiftable plun~er whose movement in the receptacle creates a suction to withdraw llquid into the receptacle thxough the hollow needle. Another type of bag may be of the type similar to a milk container having a polyethylene layer and provided with a preformed access tlibe of a type which will accommodate insertion therein of an inert gas discharging tube and outflow of air around the gas tube.
While the prefexred embodiments of this invention have been described, it will be understood that chanyes in the construction of the container may be made within the scope of the appended claims.

Claims (22)

THE EMBODIMENTS OF THE INVENTION IN WHICH AN EXCLUSIVE
PROPERTY OR PRIVILEGE IS CLAIMED ARE DEFINED AS FOLLOWS:

1. The method of encasing a corrodible product in a protective environment, consisting of the steps of inserting the product in a flexible gas impervious container, initially sealing the container at all points except at a limited opening thereof, injecting through said last-named limited opening an inert gas not miscible with air to displace or discharge air from the container until said inert gas distends said container and substantially completely fills all voids in said container, and finally sealing all openings in said container while it is substantially free of air, said gas being injected at a pressure not substantially exceeding 200 psi and the contain-ed gas pressure when all openings are finally sealed not exceeding 2 psi.

2. The method defined in Claim 1, wherein said inert gas is heavier than air and said limited second opening is positioned uppermost in said container during said gas inject-ing and sealing steps.

3. The method defined in Claim 1 or Claim 2, wherein said container is formed of material of the class including polyethylene, rubberized sheet and synthetic rubberized sheet.

4. The method defined in Claim 1 or Claim 2, wherein said inert gas is argon or a mixture of argon and nitrogen.

5. The method defined in Claim 1 or Claim 2, wherein said initial container sealing step entails coiling tightly around a first rod a portion of said container adjacent the opening through which the product is inserted, and releas-ably locking a second parallel rod to said first rod in clamping engagement with said coiled container portion.

6. The method defined in Claim 1 or Claim 2, wherein said container is heat sealed at its openings.

7. The method defined in Claim 1 or Claim 2, wherein said container is sealed by means of cement, glue or heat sealing.

8. The method defined in Claim 1 or Claim 2, wherein said product is enclosed in a gas pervious container prior to insertion in said gas impervious container.

9. The method defined in Claim 1 or Claim 2, wherein said gas filled sealed product encasing container is inserted in a second gas impervious container, said second gas impervious container is then sealed at all points except at a limited opening thereof, an inert gas is injected through said opening of said second container to displace air therefrom and substantially completely fill all voids between said first and second containers, and then sealing all openings in said second container.

10. The method defined in Claim 1 or Claim 2, wherein said inert gas is heavier than air and said container has a filling opening and a second opening located uppermost, and said first named sealing step entails folding and clamping the portion of said container adjacent said filling opening so as to close said filling opening releasably.

11. Means for protecting a product in a non-rusting non-corrosive atmosphere comprising, a flexible gas impervious container adapted to receive said product and having a product receiving open-ing and at least one additional opening for the reception of gas injecting means and for air escape, means of sealing said product receiving opening, and means for sealing each additional opening.

12. The combination defined in Claim 11, wherein said means for sealing said product receiving opening constitutes a rod around which the portion of said container adjacent said product receiving opening is tightly coiled, a second rod positioned parallel to and in contact with said coiled container portion, and means anchoring said rods in frictional compressive engagement with the coiled container portion therebetween.

13. The combination defined in Claim 11, wherein a check valve is mounted in and normally seals said air escape opening.

14. The combination defined in Claim 11, wherein said container is open at one margin and marginally sealed at all remaining margins, and a longitudinal seal extends from said open margin to an intermediate portion of said container spaced from and between opposed marginal seals to define separate filling and gas injecting openings.

15. The combination defined in Claim 14, wherein said longitudinal seal is defined by elongated linear heat seals extending from spaced points of said open margin and converging at an intermediate portion of said container.

16. The combination defined in Claim 11 wherein said container is divided by a plurality of linear heat seal lines extending from a margin defining said product receiving, gas injecting and air escape openings to an opposed sealed margin of said container, said plurality of linear heat seal lines defining separate product-receiving compartments in said container.

17. The combination defined in Claim 11, wherein each of said plurality of heat seal lines includes a pair of spaced substantially parallel seal lines extending across said container.

18. The method defined in Claim 1, wherein said in-ert gas is introduced into said container at a pressure in the order of 50 psi to 200 psi until such container is charged with said inert gas at a pressure not exceeding 2 psi .

19. The method defined in Claim 1, wherein said container is vibrated as said inert gas is introduced therein

20. The method defined in Claim 1, wherein said container is mounted upon a movable external supporting structure independent thereof prior to filling and sealing.

21. The method defined in Claim 1, wherein said product is inserted in said container through a first open-ing spaced from and at a lower level than a second contain-er opening, said initial sealing occurring at said first opening and at all points of said container except at said second opening, said gas injection and air discharge occur-ring through said second container opening.

22. The method defined in Claim 21, wherein said inert gas is heavier than air and said second opening is positioned uppermost in said container during the gas inject-ing and sealing steps.

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