EP0285761A1

EP0285761A1 - Self-generating pressure applying means for a disposable container

Info

Publication number: EP0285761A1
Application number: EP88101702A
Authority: EP
Inventors: Jan L. Dorfman; Larry M. Dugan
Original assignee: Adolph Coors Co
Current assignee: Molson Coors Beverage Co
Priority date: 1987-04-06
Filing date: 1988-02-05
Publication date: 1988-10-12
Also published as: AU616877B2; JP2581729B2; JPS63258796A; CA1333169C; NZ223131A; AU1013788A

Abstract

An expandable pouch (2) is provided for applying a pressure to a material in a container so that it may be readily dispensed therefrom and comprises two flat sheets (4,6) of a gas and liquid impermeable material in superposed relationship so as to have a length and a width and with the peripheral edge portions (12) thereof permanently sealed. A plurality of compartments (14,16) are formed in the expandable pouch by lengthwise extending semipermanent peelable strips (18). Two components (30,32) of a chemical gas generating system having a delayed action system associated therewith are located in one (14) of the compartments and one component of the two components (30,32) is located in the other compartments (16). After actuation of the two components, the one compartment (14) will gradually expand and as the material is dispensed will rupture the semipermanent peelable strip (18) between it and the next adjacent other compartment (16) to form one combined compartment with the one component in the next adjacent other compartment (16) continuing the gas generating system. This process continues until all the other compartments (16) have been expanded. Also, an expandable pouch (2) particularly designed for cooperation with a specifically shaped container (60) is provided wherein the other compartments are expanded so as to maintain a substantially constant pressure in the container.

Description

This invention relates generally to a self-generating pressure applying means, such as an expandable pouch which is adapted to be positioned in a container having a quantity of material contained therein so as to provide pressure on the material so that it may be readily dispensed from the container and in particular to a self-generating pressure applying means which is particularly suited for dispensing a fluid from a disposable container.
It has been known for many years to dispense material from a container wherein a self-generating pressure applying means is contained within the container so as to apply a pressure on the material contained within the container so that the material may be readily dispensed therefrom through suitable dispensing means. Two major requirements for such use is that the self-generating pressure applying means functions to apply a pressure within desired ranges on the material within the container as portions of the material are dispensed therefrom and to get substantially all of the material out of the container. While these requirements have been met in many instances, the size and shape of some containers in association with the materials container therein have provided problems in meeting these requirements.
This invention provides a new, improved self-generating pressure applying means, such as an expandable pouch means, which is particularly designed and constructed so that it cooperates with the container means in which it is contained to ensure that substantially all of the material contained within the container is dispensed therefrom and maintains the pressure within the container means within a desired range of pressure during the dispensing operation. The expandable pouch means of this invention is particularly useful wherever it is undesirable to add additional CO₂ to the material in the container and where it is desirable to maintain substantially constant pressure on the material in the container during the entire dispensing operation.
In the presently preferred embodiment of the invention, the self-generating pressure applying means comprises an expandable pouch means comprising two relatively flat sheets of a gas and liquid impermeable plastic material in superposed relationship and having a octagonal shape having a length and a width and with the edge portions thereof joined by permanent sealing means. The expandable pouch means is located within the container means so that as the expandable pouch means expands, as described below, it applies pressure to the material in the container means which in the preferred embodiment is a liquid, such as a beverage such as beer. The expandable pouch means is divided into a plurality of compartments by lengthwise extending strips of semipermanent, peelable sealing means. The expandable pouch means is inserted into the container means so that the lengthwise extending strips are, as much as possible, generally parallel to the longitudinal axis of the container means and will move more closely to such relationship as liquid is dispensed from the container means. Two compartments of a gas generating system are contained in one relatively large compartment in the expandable pouch means and each of the other compartments thereof contains a supply of one of the two components. When the two components are exposed in the one compartment, they react to start generating gas to create a pressure in the one compartment so that the portions of the superposed flat sheets forming the one compartment are forced apart. As fluid is dispensed from the container, the one compartment continues to expand and as it expands, it applies a force on the strip of semipermanent, peelable sealing means between the one compartment and the next adjacent other compartment until such strip is ruptured. The one component of the gas generating system in the next adjacent other compartment reacts with the components in the one compartment to continue the generation of gas in the combined one compartment and next adjacent other compartment. The expansion of the expandable pouch means continues until substantially all of the fluid has been dispensed from the container means. As successive other compartments are expanded, the expanded portion of the expandable pouch means will take a shape generally corresponding to the shape of the container means. Puncture means (not described in this application) are then actuated to let the gas pressure escape from the expandable pouch means and the container means so that they may be safely placed in the trash.
An illustrative and presently preferred embodiment of the invention is shown in the accompanying drawings in which:

Fig. 1 is a front elevational view with portions broken away illustrating an expandable pouch means and the components of a gas generating system;
Fig. 2 is a cross-sectional view taken on the line 2-2 of Fig. 1;
Fig. 3 is a cross-sectional view of a partially expanded expandable pouch means;
Fig. 4 is a cross-sectional view of a container for holding one component of a gas generating system;
Fig. 5 is a cross-sectional view, except for the dispensing means, illustrating a container means and its supporting structure in an upright position for shipping and commercial storage and a partially expanded expandable pouch means;
Fig. 6 is a view similar to Fig. 5 but with the container means in a dispensing position and after more than half of the fluid has been dispensed; and
Fig. 7 is a view similar to Fig. 5 but after substantially all of the fluid has been dispensed.

An expandable pouch means 2 of the presently preferred embodiment is illustrated in Figs. 1 - 3 and comprises two relatively flat sheets 4 and 6 of a flexible plastic material in superposed relationship and made from a gas and liquid impermeable material such as a composite material of an outside layer of a polyester with an inside coating of PVDC, a layer of polyethylene and a layer of an ionomer resin, such as that marketed by Dupont under the trade designation SURLYN®. Each of the flat sheets 4 and 6 is octagonal in shape having a length greater than its width and with peripheral edge portions 8 and 10 permanently joined together by a permanent sealing means 12 formed by heat sealing at a temperature of about 300°F. for 0.5 second. The expandable pouch 2 is formed into a first compartment 14 and a plurality of other compartments 16 by a plurality of lengthwise extending strips 18 which join together opposed portions of the flat sheets 4 and 6 using a semipermanent peelable sealing means 20 formed by heat sealing at a temperature of about 250°F. for 0.5 second. If the flat sheets 4 and 6 are formed from different plastic materials, the temperature and time would be adjusted as required to obtain the desired type of seal. Also, if desirable, a suitable adhesive could be used to obtain the desired results.
The normal operation of an expandable pouch means 2 uses some delaying system so that the chemical reaction can be started and still allow for sufficient time for expandable pouch means 2 to be inserted into the container means and suitable sealing and dispensing means applied to the container means. The delaying system for this invention is illustrated in Fig. 1 wherein the first compartment is sub-divided to three sub-compartments 22, 24 and 26. The sub-compartment 22 is formed by a lengthwise extending strip 18, as described above, extending parallel to the next adjacent permanent lengthwise extending sealed edge portions 8 and 10. The sub-compartments 24 and 26 are formed by a lengthwise extending strip 18, as described above, extending parallel to and spaced inwardly from the strip 18 forming sub-compartment 22. The lower portion 28 of the strip 18 forming the sub-compartments 24 and 26 has a reduced width for a purpose described below. A quantity of one component 30 of a two component gas generating system, such as a 50% citric acid solution, is contained in the sub-compartment 22. A tablet 32 comprising the other component of the two component gas generating system, such as concentrated sodium bicarbonate, is contained in the sub-compartment 24. A water solution 34 of sodium bicarbonate is contained in the sub-compartments 26. The outer compartments 16 each contain a quantity of the one component 30.
In operation a force is applied to the sub-compartment 22 to rupture the strip 18 so that the citric acid solution 24 flows into sub-compartment 24 to contact the other component, comprising the sodium carbonate tablet 32, and begins to react therewith to generate carbon dioxide gas. This reaction with the tablet 32 proceeds at a rate to provide the above-described delaying system to allow the expandable pouch means 2 to be inserted into the container means and suitable sealing and dispensing means applied to the container means. The generation of the carbon dioxide gas forms a pressurized force forcing the strip 18 between the sub-compartment 24 and the sub-compartment 26 to rupture at the weakened reduced width 28 to combine the sub-compartments 24 and 26. This permits the citric acid solution to flow into sub-compartment 26 and into contact with the water solution 34 of sodium bicarbonate and further react to continue the generation of carbon dioxide gas. As the generation of the carbon dioxide gas continues, the pressure within the first compartment 14 is increased so as to expand the portions of the flat sheets 4 and 6 forming the first compartment 14. The dispensing of fluid from the container means, as described below, will provide space for further expansion of the expandable pouch means 2. When the limit of the volume of the first compartment 14 is reached, further generation of carbon dioxide gas therein will result in a force being applied to the strip 18 between the first compartment 14 and the next adjacent other compartment 16 so as to rupture such strip 18. The citric acid solution 24 in the next adjacent other compartment 16 will contact the water solution 34 of sodium bicarbonate to continue the generation of carbon dioxide gas. This sequence will continue until the expandable pouch means 2 has been substantially completely expanded.
Another embodiment for the provision of the citric acid solution in the first compartment 14 is illustrated in Fig. 4 and is particularly useful when the fluid in the container means is a carbonated beverage, such as beer. A substantially rigid container 40, which in the preferred embodiment is plastic, has a closed end 42 and an open end 44. The container 40 is illustrated as being a tube but it is to be understood that it can be of any desired geometrical configuration. A barb 46 is secured to the inner surface 48 of the container 40 with its pointed end 50 facing and relatively close to the open end 44. A quantity of the citric acid solution 24 is placed in the container 40 and the open end 44 is sealed by a flexible membrane 52. The strips 18 forming the sub-compartments 22, 24 and 26 are not used in this modification so that the first compartment 14 is one unitary compartment. The filled container 40 is contained in the first compartment 14 with the water solution 34 of sodium bicarbonate. After the expandable pouch means 2 has been inserted into the container means filled with a carbonated beverage, as described below, the pressures generated by the carbonated beverage in the container means will exert a pressure on the flexible membrane 52 moving it into contact with the pointed end 50 to rupture the flexible membrane 52 and permit the citric acid solution 24 to flow into the water solution 34 of sodium bicarbonate in first compartment 14 to start the carbon dioxide gas generating system.
The location of the expandable pouch means 2 in a container means 60 is illustrated in Figs. 5 - 7. In Fig. 5, the container means 60 is supported in the upright position for shipping and commercial storage by a support member 62. The expandable pouch means 2 has a length substantially greater than the longitudinal extent of the container means 60 and a width substantially greater than the diameter of the container means 60. Therefore, in order to insert the expandable pouch means 2 through an opening 64 in the container means 60, it is necessary to apply a force in a widthwise direction to compact the expandable pouch means 2 in that direction so that its cross-sectional configuration is less than the cross-sectional configuration of the opening 64. Also, as the expandable pouch means 2 is inserted into the container means 60, it is necessary to apply a force in the lengthwise direction to push the expandable pouch means 2 into the container means 60. This results in a crumpling of the expandable pouch means 2 in the lengthwise direction. Since the material in the expandable pouch means 2 has little tendency to resile, it will remain crumpled while a dispensing means 66 for dispensing portions of the material in the container means 60 is assembled in the opening 64. In the preferred embodiment, the fluid 68, such as a carbonated beverage such as beer, is in the container means 60 prior to the insertion of the expandable pouch means 2. If desired, the expandable pouch means 2 can be inserted into the container means 60 prior to the filling of it with the fluid. The fluid level 70 is slightly below the dispensing means 66. The strip 18 forming sub-compartment 22 is ruptured prior to the insertion of the expandable pouch means 2 into the container means 60 so that the gas generating system is in operation, as described above, and the first compartment 14 has been at least partially expanded in the illustration in Fig. 5. The container means 60 is illustrated in the fluid dispensable position in Figs. 6 and 7. Another support member 72 has been previously secured to the container means 60. The support member 62 and the support member 72 have planar surfaces 74 and 76 for supporting the container means 60 on a generally horizontal surface, such as a shelf of a home refrigerator. The planar surfaces 74 and 76 also function to maintain the container means 60 in such fluid dispensable position. While it is highly preferred to use the horizontal dispensing position, it is understood that the pressure in the container means provided by the expandable pouch means would permit dispensing in other positions, some of which may require different types of dispensing means. In Fig. 6, more than half of the fluid has been dispensed from the container means 60. The first compartment 14 and several of the next adjacent other compartments 16 have been expanded, as described above, to form a combined compartment which is located adjacent to the upper longitudinally extending portion of the container means 60. In Fig. 7, the expandable pouch means 2 is substantially fully expanded and is substantially completely in contact with the inner surface of the container means 60 except for the portion defining the opening 64. After substantially all the fluid 68 has been dispensed from the container means 60, a pressure relieving device (not shown) in the dispensing means 66 is actuated and the carbon dioxide gas in the expanded pouch means 2 is removed through the dispensing means 46 so that the container means 60 and the expandable pouch means 2 are substantially at atmospheric pressure and the container means 60 can be safely placed in the trash.
When the expandable pouch means 2 is being inserted into the container means 60, the strips 18 are generally parallel with the longitudinal axis of container means 60. As explained above, the relative length of the expandable pouch means 2 causes it to be crumpled as it is inserted into the container means 60. However, the strips 18 still extend generally in the same direction as the longitudinal axis of the container means 60. As fluid is dispensed from the container means 60 and more of the other compartments 16 are expanded, the expanded portion of the expandable pouch means 2 gradually moves into a position wherein its longitudinal axis is parallel to the longitudinal axis of the container means 60, as illustrated in Fig. 6. When the expandable pouch means 2 is fully expanded, as illustrated in Fig. 7, the longitudinal axes of the expandable pouch means 2 and the container means 60 will substantially coincide.
As illustrated in Figs. 5 - 7, the container means 60 comprises a blown hollow integral plastic container means made of one piece of integrally molded plastic material, such as polyethylene terephthalate (PET), and having a hemispherical top portion 78, an annular cylindrical central portion 80, a hemispherical bottom portion 82 and a neck portion 84 defining the opening 64. The container means 60 is large enough to hold 288 fluid ounces of a beverage.
The expandable pouch means 2 may be of any size and shape so as to be commensurate with the size and shape of the container means 60 with which it is to be used. Also, the expandable pouch means 2 may be used to dispense any kind of material from the container means as is customary in this art. However, in the preferred embodiment of the invention, the expandable pouch means 2 is designed for applying pressure to a quantity of beer equal to 288 fluid ounces or 2.25 gallons in a container means 60. The following example described an expandable pouch means 2 designed for such a container means wherein the container means 60 has an overall length along its longitudinal axis of about 15.5 inches, an external diameter of the cylindrical central portion 70 of about 9.0 inches, an average wall thickness of about 0.030 inches and wherein it is desired to maintain a pressure profile within the container means between 18 and 25 psig. The expandable pouch means 2 has a overall length of about 17 inches and an overall width of about 15.5 inches and has nine compartments formed therein.
The following table lists the various parameters involved in dispensing a beverage from a container wherein the container has an overflow volume of about 10.2 liters and contains 8.52 liters of beer at a temperature of about 38°F. and at a pressure equal to that at an altitude of about 5,000 feet. In the table the head space volume is listed as 1.220799 liters. This is the volume to which the first compartment 14 will expand to before any beer is dispensed from the container. The first compartment will expand to a volume of 1.565575 liters before the peelable seam strip 18 between it and the next adjacent other compartment is ruptured. The first compartment 14 or sub-compartment 26 will contain 100 grams of sodium bicarbonate, which is more than the stoichiometric amount necessary to react with the citric acid to produce the required pressurizing gas, combined with 170 ml of water and any other desired additional ingredients.
Setup conditions:
Product Volume to be dispensed (L) 8.520001
Product Overage Volume (L) 0.0592
Absolute Pressure (PSIA) 12
Starting Gauge Pressure (PSIG) 25
Low Limit Operating Pressure (PSIG) 18
High Limit Operating Pressure (PSIG) 25
Starting Process Temperature (F) 38
Pouch/Chemical Total Displacement Vol (L) 0.35
Tap Displacement Volume (L) 0.05
Container Overflow Volume (L) 10.2
Head Space Liquid Volume (L) 0.17
The following are pouch design parameters based on the above setup conditions:
Head Space Volume (L) 1.220799
Total Charging Gas (Moles) 0.164039
Acid Required to charge to Start Press.(GMS) 10.49849
50% Conc. Acid required for Start Press.(ML) 16.93305
Theoretical sodium bicarbonate required (gms) 75.76741
Actual sodium bicarbonate included (gms) 100.000
Sodium bicarbonate in tablet (gms) 1.00
The pouch seam locations below are measured between the inside edge of the first permanent seam and the trailing edge of each peelable compartment seam:
While an illustrative and presently preferred embodiment of the invention has been described in detail herein, it is to be understood that the inventive concepts may be otherwise variously embodied and employed and that the appended claims are intended to be construed to include such variations except insofar as limited by the prior art.

Claims

1. A self-generating pressure applying means which is inserted into a container means having material contained therein so as to apply a pressure on the material so that it may be readily dispensed from the container means characterized by an expandable pouch means comprising at least two relatively flat sheets of a gas and liquid impermeable material in superposed relationship and having a length and a width, said expandable pouch means having a plurality of linearly extending edge portions, permanent sealing means for joining said superposed flat sheets along said edge portions so as to form an enclosed space therebetween, compartment forming means between said superposed flat sheets for forming at least three compartments in said expandable pouch means, said compartment forming means comprising lengthwise extending strips of a semipermanent peelable sealing means securing together superposed portions of said superposed flat sheets, said semipermanent peelable sealing means permitting separation of said superposed flat sheets in response to pressure applied thereto, gas pressure generating means in one of said compartments to increase the gas pressure in said one compartment so that the portions of said superposed flat sheets forming said one compartment are forced apart to apply pressure to separate said semipermanent peelable sealing means between said one compartment and a first next adjacent compartment so that said one compartment and said first next adjacent compartment are joined together to form a combined compartment and at least a second next compartment, and gas pressure generating means in said first next adjacent compartment to continue the generation of gas pressure to force apart the portions of said superposed sheets forming said combined compartment as said material is dispensed from said container means to separate said semipermanent peelable sealing means between said combined compartment and said at least a second next adjacent compartment so that said combined compartment and said at least said second next adjacent compartment are joined together to form a larger combined compartment.

2. A self-generating pressure applying means according to claim 1, characterized in that the compartments are of different sizes.

3. A self-generating pressure applying means according to claim 1, characterized in that the gas pressure generating means in said one compartment includes at least two components of a chemical gas generating system, and at least one of said components being confined within an enclosure having rupturable means so that said enclosure may be ruptured allowing said one component to react with another component in said one compartment to commence generating said gas pressure.

4. A self-generating pressure applying means according to claim 3, characterized by gas pressure generating means in all of the others of said compartments comprising said another component.

5. A self-generating pressure applying means according to claim 4, characterized in that the expandable pouch means is located within a container means having a gas pressure generating beverage contained therein, in that said one component of said two component chemical gas generating system in said first compartment comprises a liquid, and in that said enclosure comprising a rigid container has at least one open end located in said first compartment, a flexible membrane covering said open end and in sealed engagement therewith so as to contain a quantity of said one component in said container, and membrane rupturing means in said container and located next to said open end so as to pierce said flexible membrane when said flexible membrane is forced into said container by pressure forces generated within said container so as to release said liquid one component into said first compartment.

6. A self-generating pressure applying means according to claim 5, characterized in that the container has an inner surface, and said membrane rupturing means includes a pointed barb secured to said inner surface with the point of said pointed barb facing said flexible membrane.

7. A self-generating pressure applying means according to claim 1, characterized in that said gas generating means in said one compartment includes at least two components of a chemical gas generating system, lengthwise extending strips of a semipermanent peelable sealing means for dividing said one compartment into at least three sub-compartments, one component of said at least two component chemical gas generating system contained within a first sub-compartment, another compartment of said at least two component chemical gas generating system contained within a second sub-compartment next adjacent to said first sub-compartment so that when said lengthwise strip between said first and second sub-compartments is ruptured, said one and another component will begin to react to produce a gas pressure therein, and a quantity of said another component in a third sub-compartment located next adjacent to said second sub-compartment to react with said one component when said one and another components in said combined first and second sub-compartments have reacted to produce sufficient gases to provide a pressure to rupture said lengthwise strip between said second and third sub-compartments to continue the generation of gas.

8. A self-generating pressure applying means according to claim 7, characterized in that said lengthwise strip between said second and third sub-compartments has a weakened portion to facilitate rupturing thereof.

9. A self-pressurizing dispensing container means for beverages such as beer or a soft drink of the type having a container means, a beverage dispensing means mounted on the container means, a beverage within the container means and a self-generating pressure applying means within the container means for applying pressure on the beverage, characterized by a hollow plastic container means made of one piece of integrally molded plastic material for holding a beverage to be selectively dispensed therefrom when located in a dispensing position, beverage dispensing means mounted on said container means, said container means having an elongated central generally cylindrical wall portion, an integral generally hemispherical closed first end wall portion, and an integral generally hemispherical second end wall portion having a central longitudinally extending neck portion with a relatively large diameter central opening of sufficient size for filling said container means with a beverage and for inserting said pressure applying means and having means for securing said dispensing means thereto and having a longitudinal axis extending through said central opening, support means fixedly attached to said container means supporting and maintaining said container means in said dispensing position, self-generating pressure applying means in said container means including an expandable pouch means comprising at least two relatively flat sheets of a gas and liquid impermeable material in superposed relationship and having a length and a width wherein said length is greater than said width, said expandable pouch means having a plurality of linearly extending edge portions, permanent sealing means for joining said superposed flat sheets along said edge portions so as to form an enclosed space therebetween, compartment forming means between said superposed flat sheets for forming at least three compartments in said expandable pouch said compartment forming means comprising lengthwise extending strips of a semipermanent peelable sealing means securing together superposed portions of said superposed flat sheets, said semipermanent peelable sealing means permitting separation of said superposed flat sheets in response to pressure applied thereto, gas pressure generating means in one of said compartments to increase the gas pressure in said one compartment so that the portions of said superposed flat sheets forming said one compartment are forced apart to apply pressure to separate said semipermanent peelable sealing means between said one compartment and a first next adjacent compartment so that said one compartment and said first next adjacent compartment are joined together to form a combined compartment and at least a second next adjacent compartment, gas pressure generating means in said first next adjacent compartment to continue the generation of gas pressure to force apart the portions of said superposed sheets forming said combined compartment as said beverage is dispensed from said container means to separate said semipermanent peelable sealing means between said combined compartment and said at least a second next adjacent compartment so that said combined compartment and said at least said second next adjacent compartment are joined together to form a larger combined compartment, and said expandable pouch means being located within said container means so that said lengthwise extending strips extend generally in the same direction as said longitudinal axis of said container means.

10. A self-pressuring dispensing container according to claim 9, characterized in that the gas pressure generating means in said one compartment includes at least two components of a chemical gas generating system, and at least one of said components being confined within an enclosure having rupturable means so that said enclosure may be ruptured allowing said one component to react with another component in said one compartment to commence generating said gas pressure.