A CONTAINER FOR LIQUIDS

Abstract: A liquid packaging unit includes an outer orthogonal parallelepipedic casing (3) comprised of stiff material, and an inner container (1) comprised of flexible material. The container (1) has a generally spherical shape when in a fully inflated state. The casing (3) has an inner perimeter in a plane that includes two parallel and diametrically opposite edges of the casing and that coincides generally with the perimeter of the container at the equator thereof. The equator of the container is located in the aforesaid plane of the casing. The area of the container coincides essentially with the internal area of the six-sided casing.

Description: A CONTAINER FOR LIQUIDS The invention relates to a liquid container of the kind that includes an outer generally orthogonal and parallelepipedic casing made of a stiff material, and an inner container made of flexible material. It is well known in the distribution of liquid substances to use cardboard cartons which have been made impervious, by coating the cardboard with plastic. These cartons are of a disposable character and provide an attractive high-grade fuel and are collected and used as such. However, the cartons must be cleaned prior to collection, for reasons of hygiene. This constitutes a problem and requires work (cleaning) and energy (hot washing water) . It is also known to manufacture liquid packaging units that comprises a stiff outer casing which imparts structural strength and rigidity to the packaging unit, and a thin liquid-containing impervious container that is supported by the casing. Examples of such liquid packaging units are described in SE-B-344 927, EP-A10 749 991, EP-A1-0 326 730 and EP-A2-0 136 239, for example. Some of these known packaging units are established by inserting the filled container into the casing and affixing the container to the casing with the aid of a glue joint or the like. One problem with these known packaging units is that the container must still be relatively shape-rigid. Certain problems also occur with respect to emptying liquid from the container. Another problem resides in the ability to reseal the packaging unit effectively between those occasions when only some of the liquid contained in the packaging unit is poured therefrom. An object of the present invention is to provide a packaging unit of the kind defined in the introduction that can be readily emptied of its liquid content, that enables the empty container to be readily removed from its outer casing, that will enable a full container to be readily inserted in said casing in a correct stable position therein, that will reduce the risk of liquid being trapped m the container when emptying said container, that provides a support for the container over a major part of its surface against the casing walls, and that will enable the use of a thin-walled container made of flexible material that may be generally non-stretchable . This object is achieved either completely or partially with the inventive liquid packaging unit defined in the accompanying independent Claim. Further embodiments of the liquid packaging unit will be apparent from the accompanying dependent Claims. In the case of a preferred basic design, the inventive liquid packaging unit comprises a thm-walled flexible spherical plastic container which is enclosed around its equatorial circumference in a rectangular frame whose inner perimeter coincides with the equatorial circumference of the container. The casing has the form of an orthogonal box and the frame is dimensioned to be received in a diagonal plane through the casing, i.e. a plane that is pitched by two diametrically opposed and mutually parallel casing edges. This ensures that the actual container will be held stably in position in the casing. The geometrical conditions are such that the wall area of the container will correspond essentially to the wall area of the casing, so that the container walls will be supported by the container over substantially the whole of their surface area. One container half s fastened to an adjacent part of the casing in a zenitn region of said container half relative to the equator. Thus, when emptying the container, the other half of the container will move into the container-half fastened to the casing in said zenith region, wherewith the chosen geometry minimises the risk of liquid being trapped in "dead" container spaces when said container collapses during the emptying sequence. In preferred embodiments of the invention, a conduit or passageway extends from the container and through the casing, preferably at an upper corner edge which is parallel with a casing wall that forms the packaging unit base surface and that is normally horizontal. The conduit will conveniently include a valve means which functions to block the conduit when the packaging unit is correctly orientated vertically, i.e. with the base surface horizontal, and which is adapted to open when the packaging unit is inclined from the vertical, for instance is tipped to allow liquid to be poured through the conduit. The conduit which extends through a corresponding opening in the casing may be comparatively short and will preferably terminate at the outer surface of the casing. The opening in the casing may be sealed with tear-off adhesive tape, suitably provided with a grip tab. If desired, the conduit may be caused to extend to an opening in the upper part of the casing, for instance an upper corner between two side walls and an upper wall. The conduit may also be connected to the bottom zenith of the container if so desired. Because the container plane coincides with the contours of a diagonal section through the container, the container can be mounted stably in the casing, solely by inserting the frame (and the container) into the casing through an open casing wall. Correspondingly, the empty container can be readily removed from the casing, even mechanically, after having opened a container wall (i.e. a wall which is perpendicular to the plane of the frame), since the frame forms an object that can be conveniently gripped and that is situated in a predetermined position relative to the casing. A fresh liquid container can be inserted into the container in the same relatively simple fashion, since positioning and gripping of the container is facilitated by the container frame. The partially filled container (filled approximately to half of its maximum capacity) is inserted into the casing so as to essentially fill the casing with liquid, whereafter the conduit/valve is aligned with its associated opening in the casing. The invention will now be described in more detail by way of example with reference to the accompanying drawing. Fig. 1 is a schematic side view of a container intended for an inventive packaging unit. Fig. 2 illustrates the container of Fig. 1 in a fully inflated state schematically and from above. Fig. 3 is an oblique perspective view of the casing of the packaging unit and shows the frame and the container inserted in a correct position in the casing. Fig. 4 is a sectional view of the liquid packaging unit taken on the line IV-IV in Fig. 3, and shows the container emptying conduit and its associated valve means. Fig. 5 is a view of a filled container according to Fig. 2 inserted in a box-like casing that has rigid planar walls . Figs. 1 and 2 illustrate a container 1 that can be assumed to be comprised of a flexible but unstretchable material and which can also be assumed to have a spherical shape when fully inflated. The container 1, however, is surrounded in an equatorial plane 11 by a rectangular frame 2 whose perimeter coincides with the circumference of the container 1 at said plane 11. The casing 3 will preferably have a square bottom surface having the side length b and the height a. The container 1 has a surface area that corresponds approximately to the surface area of the six-sided casing 3. The circumference 11 of the container 1 corresponds roughly to the perimeter of the frame 2. If the casing shall have a volume of 1 litre (1 dm 3 ), it may have the edge measurements a = 0.852 dm, b = 1.085 dm, wherewith the frame 2 will have the edge length a = 0.852 dm and c (the diagonal measurement of the casing) = 1.534 dm. The container may have a diameter of 1.38 dm, wherewith the container and casing will have an area of approximately 6 dm 2 . When completely filled and free from the frame 2, the spherical container 1 will have a maximum volumetric capacity of about 1.384 dm 3 , although the container is filled solely to a liquid volume of 1 dm 3 (i.e. the volume of the casing 3) . Because the area of the container 1 is roughly the same as the inner area of the orthogonal six-sided casing, the container 1 will be supported over essentially the whole of the inner surface of the casing. Because one-half of the container is fastened at its zenith region 17 (relative to the equator 11) to the upper corner edge -of the casing 3 (at half the length of said corner edge) , the other half of the container is able to move into its fixed half, essentially without folds or wrinkles forming when emptying the packaging unit. The risk of liquid being trapped in the container is minimised by virtue of the basic spherical shape of the container. This also ensures that the container can be emptied completely. Fig. 4 illustrates schematically an emptying conduit 7 which extends through an opening 31 provided in the casing at one corner thereof between a casing side wall and the casing top wall at half the length of the corner edge. The conduit 7 is connected through an adjacent part of the container 1 and includes a valve 8 which has a throughflow chamber whose bottom part is comprised of an upwardly concave surface 81, wherewith the conduit 7 extends from the container 1 through the undermost part of the surface 81. The resultant opening 82 in the surface 81 is blocked by a ball 83 when the packaging unit is vertically orientated. As the packaging unit is tipped, the ball 83 will roll away from the opening, such as in the case when pouring liquid from the container. The conduit 7 extends from a zenith point 17 on the container 1 relative to the equator 11. Arranged around said zenith point 17 is a fastener element, for instance double-sided adhesive tape 18, which anchors this surface region of the container 1 around the zenith 17 to the inner surface of the adjacent casing part. One advantage afforded by the spherical basic shape of the container 1 is that the container part 19 will move progressively from the equator 11 and into the container part 20 (these parts being delimited by the equator 11) , so as to minimise the risk of wrinkles and liquid entrapment . The frame 2 may be a separate element that is releasably fastened to the container 1. Alternatively, the frame may be made an integral part of the container 1. As will be seen from Fig. 4, the conduit 7 may terminate at the outer corner surface of the casing 3, and that adhesive sealing tape 24 provided with a grip tab may be placed over the opening 31 so as to guarantee sealing of the packaging unit . Fig. 5 indicates an alternative embodiment of a packaging unit in which the container zenith 17, i.e. the connection of the conduit 7 with the container shown in a broken line, lies at the bottom edge of the casing. The container is preferably fastened to the casing in its adjacent bottom-edge region with the aid of a fastener element 18 or the like. The conduit 7 is shown to extend around roughly half of the casing perimeter on the inside of said casing up to the opening 31, which lies conveniently at the upper container edge, for instance in one corner, or midway of the angle between a casing wall and the casing top wall as in the illustrated case.

Claims: CLAIMS 1. A liquid packaging unit including an outer orthogonal parallelepipedic casing (3) comprised of stiff material, and an inner container (1) comprised of flexible material, characterised in that the container (1) has a generally spherical shape when in a fully inflated state; in that the casing (3) has an inner perimeter in a plane that includes two parallel and diametrically opposite edges of the casing, said perimeter coinciding generally with the perimeter of the container at the equator thereof; in that the container equator is located in said casing plane; and in that the area of the container coincides essentially with the internal area of the casing. 2. A liquid packaging unit according to Claim 1, characterised in that the container (1) has a rigid rectangular frame (2) around its equator, wherein the size of said frame corresponds to the cross-sectional size of the casing (3) in said plane. 3. A liquid packaging unit according to Claim 1 or 2, characterised in that the base wall of the casing (3) is square; and in that the casing has six flat walls. 4. A liquid packaging unit according to any one of Claims 1-3, characterised by conduit means (7) connected to the container (1) and extending out through an opening (31) in an upper casing edge. 5. A liquid packaging unit according to Claim 4, characterised in that the conduit means (7) includes a check valve (8) . 6. A liquid packaging unit according to Claim 5, characterised in that the check valve (8) is adapted to open when the unit is tipped from a predetermined storage position to a position in which fluid shall be emptied through said conduit means (7); and in that the check valve is adapted to close automatically when the packaging unit is in its storage position. 7. A liquid packaging unit according to any one of Claims 1-6, characterised in that the casing (3) has an openable wall panel through which a used container can be removed and replaced with a new filled container. 8. A liquid packaging unit according to Claim 4, characterised in that the container (1) is fastened to an adjacent part of the casing in a region (18) at the zenith of the container (1) as viewed from its equator, whereas the opposite wall part of the container relative to said equator can move freely; and in that said conduit means connects with the zenith region of the container. 9. A liquid packaging unit according to any one of Claims 1-8, characterised in that the conduit means (7) terminates at the outer contour surface of the casing.

Inventors: MAEKINEN ESA, MAEKINEN, ESA
Applicants: MAEKINEN ESA, MAEKINEN, ESA
Application year: 1999
Main classification: B65D77
IPC codes: B65D77