BAG-IN-BOX

Abstract: A bag-in-box (6) having at least two bags (8, 9) housed in an external box (7). The two bags (8, 9) comprises first and second bags each formed of sheet-like material and flexible. The first bag (8) serves as a container for containing a content therein and the second bag (9) serves as a pressing member expandable upon injection of pressurized fluid thereinto to compress the first bag (8). The first bag (8) is separated from the second bag (9) and is stacked thereon in the external box (7). Alternatively, one of the first and second bags is positioned inside the remaining one of the second and first bag. Each of the first and second bags (8, 9) has tubular shape both ends of which are fuse-bonded. Gusset type bag is also available as the first and second bags (8, 9).

Description: BACKGROUND OF THE INVENTION The present invention relates to a bag-in-box and more particularly, to a type thereof in which a foldable bag formed of sheet-like material is accommodated in an external box. In a conventional paper cup dispenser for dispensing a cup of beverage such as refreshing drinks (juice, cola etc.) and coffee or the like, a returnable tank which is capable of recovery and reuse is employed for storing therein a syrup or concentrated liquid. Fig. 18 shows a conventional dispenser 1 which uses the returnable tank T. The dispenser 1 is connected to the returnable tank T which contains syrup or concentrated liquid. The returnable tank T is connected to a gas bottle 10 (carbonic acid gas bottle) through a decompression valve V. Beverage in the returnable tank T is pressurisingly injected into the dispenser 1 by the application of carbonic acid gas into the tank T. According to the structure, it is rather time-consuming and uneconomical for the recovery of the returnable tank T, refilling of the beverage thereinto, and cleaning and sterilisation thereto. Further, the returnable tank T must be formed of metal for providing fluid-tightness and high-pressure resistivity, and therefore, the resultant tank becomes costly and heavy. In order to overcome these drawbacks, a throwaway bag-in-box has been proposed instead of the returnable tank. According to the bag-in-box, a foldable bag or container formed of plastic material is accommodated in a corrugated cardboard box for transporting, depositing and storing a liquid. Such bag-in-box provides light weight structure, long term durability, and easy handling performance, and is inexpensive and convenient for transportation and storage of liquids in comparison with conventional glass bottles, tanks, and tin-plate cans. In view of the above, there have been proposals for the applications of the bag-in-box to a variety of industrial fields for transporting and storing liquidised food and chemicals in a bag formed of flexible single film, flexible laminated film, a plurality of laminated films, or composite film, those providing pressure resistivity and chemical resistivity. Next, a conventional dispenser system utilising a conventional bag-in-box will be described with reference to Fig. 19. A dispenser 1 is connected, through an aspiration pump P, to a bag-in-box 6 filled with syrup or concentrated liquid, and the aspiration pump P is connected to a carbonic acid gas bottle 10 through a decompression valve V. The aspiration pump P is activated by the application of the carbonic acid gas thereto from the gas bottle 10, so that the syrup in the bag-in-box 6 is aspirated and introduced into the dispenser 1. However, according to this type of system, since the syrup is aspirated and injected by the utilisation of negative pressure, which pressure is provided in a fluid path bridging between the bag-in-box 6 and the aspiration pump P, external air is also taken into the system through a connecting portion and through the bag. As a result, the syrup may be contaminated by micro-organisms and dust laden in the external air. Accordingly, the aspiration type system has a fatal disadvantage in view of sanitation. Further, since the aspiration pump P is employed the overall system becomes costly, and periodical inspection and maintenance is required for the pump P and the fluid path for cleaning and sterilising the same. Patent specifications WO 85/03056 and FR-A-2213669 disclose a container including at least two flexible bags at least the first of which serving as a container for a fluid content, and at least one second bag being expandable on injection of fluid therein to provide compression of the content of the at least first bag to discharge its contents. Additionally, Patent specification FR-A-2213669 which corresponds to the nearest prior art discloses at least one first bag positioned inside at least one second bag. GB-A-951,437 discloses plastic bags formed with a gusset. Such bags are formed from a flattened tubular length of plastic material which is then folded and heat sealed to give the desired form. However, GB-A-951,437 makes no reference to a bag-in-a-box. It is an object of the present invention to overcome the above-described drawbacks and disadvantages and to provide an improved bag-in-box. Another object of the present invention is to provide such a bag-in-box free from contamination of a content in the bag. Still another object of this invention is to provide a bag-in-box capable of being used to discharge the content from the bag under pressure, and capable of being fitted to a conventional dispenser unit. According to the present invention, there is provided a bag-in-box comprising at least two bags having a first positioned inside the other one of said two bags, each formed of sheet-like material, said at least two bags being flexible and foldable; a single mouthpiece being mounted to said two bags so as to communicate therewith; and an external box for housing said at least two bags, said first bag serving as a container for containing therein a content, and said second bag serving as a pressing member and being expandable upon injection of pressurised fluid thereinto, whereby said first bag is compressed to discharge said content therefrom; characterised in that at least one of said first and second bags comprises a gusset type bag which comprises; a tubular film member having end edges; and a fuse-bonded portion which is so formed that portions of said tubular film member are fuse-bonded, said tubular film member comprising; a pair of first folding lines defining a front wall therebetween; a pair of second folding lines defining a rear wall therebetween; and a pair of third folding lines each defining an internally folded gusset portion each having first and second walls confronting with each other, said first wall confronting said front wall and being defined by said first folding line and said third folding line and said second wall confronting said rear wall and being defined by said second folding line and said third folding line; and said fuse-bonded portion comprising; a pair of first fuse-bonding lines obliquely extending from said end edges and from a centre of said front wall to said first folding lines, said pair of first fuse-bonding lines fuse-bonding said front wall with said first wall at said end portions; and a pair of second fuse-bonding lines obliquely extending from said end edges and from a centre of said rear wall to said second folding lines, said pair of second fuse-bonding lines fuse-bonding said rear wall with said second wall at said end portions; and in that said single mouthpiece comprises: two flanges, each adapted to be connected to said first and second bags respectively; and inner and outer tubular members in fluid communication with said first and second bags respectively, the fluid communication between said tubular members being blocked. The first bag may be positioned inside the second bag or the second bag may be positioned inside the first bag. The pair of first and second fuse-bonding lines may define ends of the tubular member. The bag may further comprise third fuse-bonding lines fuse-bonding the end edges of the front wall and the first wall and fourth fuse-bonding lines fuse-bonding the end edges of the rear wall and the second wall. The third and fourth fuse-bonding lines may define ends of the tubular member. Brief Description of Drawings In the drawings:- Figure 1 is a schematic elevation showing a dispenser system which employs a bag-in-box; Figure 2 is a cross-sectional view showing a bag-in-box (although not a bag-in-box of the invention). Figure 3 is an exploded view showing a bag-in-box; Figure 4 is a perspective view showing the bag-in-box of Figure 3; Figure 5 illustrates a bag-in-box provided with a mouthpiece according to the invention; Figure 6 is a plan view of the embodiment illustrated in Figure 5; and Figure 7 is a cross-sectional view taken along the line XVI-XVI of Figure 6; Figures 8 to 12 illustrate a "gusset-type" bag used in a bag-in-box according to this invention, and in which Figure 8 is a plan view of the bag, Figure 9 is a cross-sectional view taken along the line XXIX-XXIX of Figure 8, Figure 10 is a front view of the bag, Figure 11 is a side view of the bag, and Figure 12 is a perspective view of the bag inflated into which a content is filled; Figures 13 to 17 illustrate alternative forms of a "gusset-type" bag used in a bag-in-box according to this invention, and in which Figure 13 is a plan view of the bag, Figure 14 is a cross-sectional view taken along the line XXXIV-XXXIV of Figure 13, Figure 15 is a front view of the bag, Figure 16 is a side view of the bag, and Figure 17 is a perspective view of the bag inflated into which a content is filled; Figure 18 is schematic elevation showing a conventional dispenser system which employs a conventional returnable tank; and Figure 19 is a schematic elevation showing a conventional dispenser system which uses a conventional bag-in-box. Detailed Description of the Preferred Embodiments The general mode of operation of a bag-in-box will be described with reference to Figures 1 to 4. Figure 1 shows a dispenser system provided with a compression and extraction device which includes a bag-in-box. A dispenser 1 is connected to bag-in-boxes 6 and 6 each housed in pressure resistive containers 2 and 2. Further, a carbonic acid gas bottle 10 (pressure source) which is a part of the compression and extraction device is connected to the bag-in-boxes 6, through a decompression valve V. Figure 2 shows details of the pressure resistive container 2 and bag-in-box 6 those used in Figure 1. The bag-in-box 6 includes an external box 7 formed of corrugated cardboard as an armoured member, and two bags 8 (first bag) and 9 (second bag) housed in the external box 7. In the box 7, one of the bags 9 (upper bag or second bag) is mounted on the other bag 8 (lower bag or first bag). The lower bag 8 contains a beverage syrup and serves as a liquid container member. The lower bag 8 is formed with an outlet 8 OUT connected to the dispenser 1. On the other hand, the upper bag 9 serves as a pressurising or inflatable member to compress the container member 8. The upper bag 9 is formed with a pressure inlet 9 IN connected to the carbonic acid gas bottle 10. Next, liquid extracting process will be described with reference to Figures 3 and 4, in which the pressure resistive container 2 houses therein the bag-in-box 6, and the bag-in-box 6 is connected to the dispenser 1. As best shown in Figure 3, the pressure resistive container 2 comprises a main container body 3 and a front lid 4. The main container body 3 has an open end provided with engagement pins 3a, and the front lid 4 has side edges provided with engagement holes 4a. The front lid 4a is formed with bores 4 O 4 O at positions corresponding to the inlet 9 IN and outlet 8 OUT. Further, the external box 7 of the bag-in-box 6 is formed with perforations 7a 7a at positions corresponding to the inlet 9 IN and outlet 8 OUT. The bag-in-box 6 is first inserted into the main container body 3 through its open end so as to position one of the box faces at which the perforations are formed at the open end of the main container body 3, and then the perforations 7a 7a are cut away, so that the outlet 8 OUT and inlet 9 IN are exposed to the atmosphere. Thereafter, the front lid 4 is placed on the open end of the main container body 3 and the engagement pins 3a are engaged with the engagement holes 4a to fixedly secure the front lid 4 to the main container body 3. In this case, the outlet 8 OUT and inlet 9 IN extend through the bores 4 O and 4 O as shown in Figure 4. Then, the outlet 8 OUT and the inlet 9 IN are connected to the dispenser 1 and the carbonic acid gas bottle 10, respectively. For dispensing syrup from the dispenser 1, pressurised carbonic acid gas at a service pressure of 0.02 to 10 kg/cm² is injected from the gas bottle 10 into the pressurising bag 9. As a result, the bag 9 is gradually inflated to compress the syrup containing bag 8. and the syrup is discharged from the bag 8 under pressure and is introduced into the dispenser 1. Incidentally, four rectangular corner portions at a bottom of the external box 7 are provided with triangular members C as shown in Figure 2. These space occupying members C are affective for completely discharging syrup out of the syrup containing bag 8 when the bag 9 is inflated. As described above, a pressurising content extraction system is adopted for discharging the content from the bag-in-box. Therefore, the content is not contaminated by micro-organism due to aspiration of ambient air into the system. This provides advantages in terms of sanitation. Furthermore, the resultant content extraction device is simple in construction, and therefore, an economical device results which is easy to maintain and inspect. The bag-in-box of the present invention is similar in many respects to the dispensing system illustrated in Figures 1 to 4 but differs in that inter alia the bag-in-box of the present invention requires only a single mouthpiece to give access to both bags, and in that one bag is positioned inside the other. A bag-in-box having a mouthpiece according to the present invention will now be described with reference to Figures 5 - 7. In the said bag-in-box, open ends at each one side of the tubular film members are thermally sealed together and, furthermore, one of the longitudinal edge line portion of the inner bag 18 is also fuse-bonded with one of the longitudinal edge line portion of the outer bag 19 as shown by 18S (19S) in Figure 15. These features do not form part of the invention. A mouthpiece is integrally assembled together at a single location as best shown in Figure 5. To be more specific, the mouthpiece 22 of the invention is integrally provided with a lower flange 23 adapted to be connected to the inner bag 18 and an upper flange 24 adapted to be connected to the outer bag 19. Further, the mouthpiece 22 also includes inner and outer tubular members 25 and 26 in fluid communication with inner and outer bags, respectively, yet fluid communication between the tubular members 25 and 26 is blocked. The mouthpiece 22 is detachably connected with a plug member 27 as shown in Figure 14. The plug 27 includes inner and outer pipes 28 and 29 in fluid communication with the inner and outer tubular members 25 and 26, respectively upon attachment of the plug onto the mouthpiece 22. The dual bags for use in a bag-in-box shown in Figures 5 to 7 can be employed in various ways. That is, different kinds of materials can be filled in the inner and outer bags 18 and 19 so as to selectively take out the material from the integral dual bag. For example, the inner bag 18 is filled with a raw material syrup, and the outer bag 19 is filled with diluent water. When enjoying drinking, controlled amounts of the syrup and diluent water are discharged from the bags. Therefore, such dual bags are available for a source of mixed-drinks. Further, the inner bag 18 is filled with a material required to have constant temperature, such as elevated or cooled temperature, and the outer bag 19 is filled with heat insulating material to keep the temperature of the material. Further, if gas or suitable liquid is filled in the outer bag 19, the material filled in the inner bag 18 is subjected to proper cushioning effect. According to the invention at least one of the bags 18 and 19 is a gusset-type bag. An embodiment of a gusset-type bag used in a bag-in-box of this invention will now be described with reference to Figures 8 to 12. In the production of the bag of this embodiment, tubular thin plastic film formed of polyethylene is prepared, and two open ends of the tubular film are thermally fuse-bonded by a heat sealer to give a bag shape. The tubular film member is folded along the direction in parallel with an axial direction thereof such that the cross-sectional shape has a combination of M-shape and W-shape as shown in Figure 9. As a result, a bag 61 has internally folded portions, ie, gusset portions 63 63 (internal V figure of M figure, and internal inverted V figure of W figure, which V-shape consists of first and second walls 63a and 63b), and external walls 62, 62 ie a front (upper) wall 62a and a rear (lower) wall 62b (remaining leg portions of M figure and remaining arm portions of W figure). Furthermore, two external folding lines 64x and 64y of M figure are in alignment with and in contact with or are positioned close to each other. The same is true with respect to two external folding lines 64x and 64y of W figure. The external folding lines 64 include the pair of first folding lines 64x and 64x defining the front (or upper) wall 62a therebetween, and the pair of second folding lines 64y and 64y defining the rear (or lower) wall 62b therebetween. Thus, the first wall 63a of the gusset portion 63 is defined by the first folding line 64x and the third folding line 63c, and the second wall 63b of the gusset portion 63 is defined by the second folding line 64y and the third folding line 63c. At each of the open edges of the tubular film body, a centre point of the upper wall 62 is marked as at 62c. Further, at each of the external folding lines 64, a point 64c is marked. Then, a line 65 connecting between the points 62c and 64c is drawn, and the tubular film body is cut along the lines 65, so that each of the remaining triangular portions 62r are removed. Thereafter, outer wall and confronting internally folded gusset portion 63 are fuse-bonded together by means of a heat sealer along the line 65. That is, a wall 62a is fuse-bonded to a wall 63a along the line 65, and a wall 62b is a fuse-bonded to a wall 63b at the line 65. As a result, fuse-bonded portions 66 are provided along the lines 65, and the tubular film body serves to provide a bag shape having completely confined space. A pair of fuse-bonding portions 66 at the front wall side is referred to a pair of first fuse-bonding lines, and a pair of fuse-bonding portions 66 at the rear wall side is referred to a pair of second fuse-bonding lines. The upper wall 62a of the bag body 62 is provided with a mouthpiece 67 through which a content is injected into or discharged from the bag. The mouthpiece 67 has a flange 67f to which a film member is fuse-bonded. Here, each of the gusset portions or internally folded portions 63 and 63 has an innermost folding line 63c (the pair of third folding lines) as best shown in Fig. 9.If the gusset portions 63 are folded such that the two innermost folding lines 63c and 63c are in contact with or positioned close to each other, the folded bag 61 will provide a generally square cross-section upon complete inflation of the bag because of the content injection thereinto. On the other hand, if the gusset portions 63 are so folded such that the two innermost folding lines 63c and 63c are spaced away from each other the folded bag will provide a generally oblong cross-section upon complete inflation of the bag 61. Further, there is another factor to determine the cross-sectional shape of the inflated bag 61. That is, inclination of the cut-line 65 is also a determinative factor. For example, in Fig. 8, if the length s is equal to the length t, the bag will provide the square cross-section upon inflation, whereas if the length t is larger than the length s, the bag will provide the oblong cross-section upon inflation. Here, the line s extends from the central edge point 62c in a direction parallel with the longitudinal direction of the bag, and the line t extends from the point 64c at the externally folded line 64 in a direction perpendicular to the longitudinal direction of the bag 61, and lengths s and t are determined by the intersection of the two lines. Next, operation mode of thus folded gusset type bag 61 will be described. When the folded bag 61 for use in a bag-in-box is subjected to content injection through the mouthpiece 67, the gusset portions 63 63 are gradually stretched and the internally folded line portions 63c are urged outwardly. As a result, internal V-shaped gusset portions 63 will become substantially flat portions upon complete content injection as shown in Fig. 12, so that two side walls are provided in addition to the already provided upper and lower walls 62a and 62b. With respect to the longitudinal end portions having the fuse-bonded portions 66, each of the end portions is folded generally by 90 degrees at a line connecting between the upper and lower points 64c and 64c in Fig. 8 upon content injection. Upon complete inflation, the four fuse bonded portions 66 will be diagonally oriented as shown in Fig. 12. As a result, a generally rectangular or cubic bag 61 is obtainable. During content injection into the bag 61 and after completion of the content injection, tensile stress is uniformly applied to a length of the fuse-bonded portions 66 without application of stress concentration to a specific portion thereof. Further, since the inflated bag 61 will provide rectangular or cubic configuration, the bag is housed in conformance within the internally rectangular or cubic space of the external box (see box 7 in Fig. 3) which protects the bag. As a result, the bag 61 is not subject to excessive local pressure against the external box. Another embodiment of a gusset-type bag for use in a bag-in-box according to the present invention will next be described with reference to Figs 13 to 17. Similar to the embodiment shown in Figs. 8 to 12, a bag 61', of this embodiment has internally folded gusset portions 63 and 63, and upper and lower walls 62a and 62b. Further, at each end portion of the tubular film body 62A, slanting fuse bonded portions 66 are provided by the manner the same as that of the embodiment of Figs. 8 to 14. However, in this embodiment, the triangular end portions 62r (Fig. 28) are not removed, and open ends of the tubular film body 62A are also fuse bonded. More specifically, an open end portion 62 O of the upper wall 62a is fuse-bonded with an open end portion 62 O of the neighbouring internally folded portion 63a, and open end portion of the lower wall 62b is fuse-bonded with an open end portion of the neighbouring internally folded portion 63b. As a result, other linear fuse-bonded portions 68 are provided, and triangular portions 69 each defined by the externally folding line 64, the slanting fuse-bonded portion 66 and the linear fuse-bonded portion 68 are provided. Four triangular portions 69 are provided at each longitudinal end portion of the bag 61'. The gusset portions 63 are stretched and the originally V-shaped gusset portions 63 will be converted into flat shape upon content injection, and further, the four slant fuse-bonded portions 68 will provide diagonal configuration. Furthermore, in this embodiment the linearly fuse-bonded portion 68 of the upper triangular portions 69 and the linearly fuse-bonded portion 68 of the lower triangular portions 69 become close to each other as shown in Fig. 37. As a result, the upper and lower triangular portions 69 protect the gusset portions 63a' and 63b' at longitudinal end portions of the bag 61'. In this paragraph, the terms "upper" and "lower" correspond to upper side 62a and lower side 62b, respectively. In this embodiment, uniform tensile stress is applied to each length of fuse-bonded portions 68 without application of stress concentration to a local portion thereof. Further, generally rectangular or cubic bag is obtainable whose shape is in conformance with the internal rectangular or cubic space of the external box.

Claims: A bag-in-box (6) comprising at least two bags having a first bag (18) and a second bag (19), one (18) of said two bags being positioned inside the other one (19) of said two bags, each formed of sheet-like material, said at least two bags being flexible and foldable; and a single mouthpiece (22) being mounted to said two bags so as to communicate therewith; an external box (7) for housing said at least two bags, said first bag (18) serving as a container for containing therein a content, and said second bag (19) serving as a pressing member and being expandable upon injection of pressurised fluid thereinto, whereby said first bag (18) is compressed to discharge said content therefrom; characterised in that at least one of said first (18) and second (19) bags comprises a gusset type bag which comprises; a tubular film member having end edges; and a fuse-bonded portion which is so formed that end portions of said tubular film member are fuse-bonded, said tubular film member comprising; a pair of first folding lines (64x) defining a front wall (62a) therebetween; a pair of second folding lines (64y) defining a rear wall (62b) therebetween; and a pair of third folding lines (63c) each defining an internally folded gusset portion (63) each having first and second walls (63a, 63b) confronting with each other, said first wall (63a) confronting said front wall (62a) and being defined by said first folding line (64x) and said third folding line (63c), and said second wall (63b) confronting said rear wall (62b) and being defined by said second folding line (64y) and said third folding line (63c); and said fuse-bonded portion comprising; a pair of first fuse-bonding lines (65, 66) obliquely extending from said end edges and from a centre of said front wall (62a) to said first folding lines (64x), said pair of first fuse-bonding lines (65,66) fuse-bonding said front wall (62a) with said first wall (63a) at said end portions; and a pair of second fuse-bonding lines (65, 66) obliquely extending from said end edges and from a centre of said rear wall to said second folding lines (64y), said pair of second fuse-bonding lines (65, 66) fuse-bonding said rear wall (62b) with said second wall (63b) at said end portions; and in that said single mouthpiece (22) comprises: two flanges (23, 24), each adapted to be connected to said first (18) and second (19) bags respectively, and inner (25) and outer (26) tubular members in fluid communication with said first (18) and second (19) bag, respectively, the fluid communication between said tubular members being blocked. The bag-in-box as defined in claim 1 characterised in that said first bag (18) is positioned inside said second bag (19). The bag-in-box as defined in claim 1 characterised in that said second bag (19) is positioned inside said first bag (18).

Inventors: TAKAHASHI, YUTAKA C/O KIRIN BEER KABUSHIKI KAISHA, YAMAWAKE, SHIN C/O KIRIN BEER KABUSHIKI KAISHA
Applicants: KIRIN BEER KABUSHIKI KAISHA
Application year: 1988
Main classification: B65D77
IPC codes: B65D83, B67D1, B65D77