Field of the Invention

This invention relates to a bulk fluid container assembly. It relates specifically but not exclusively to a bulk fluid container assembly which may be suitable for holding and/or maturing wines and/or spirits.

Background of the Invention

Bulk fluid containers have been commonly used in industry. By bulk, we mean containers having a capacity typically between 600 litres and 20,000 litres, although much larger containers have at times been used for truck haulage.

One of the most common forms of bulk containers for fluids is one which has a footprint similar to that of a standardized pallet. This has obvious advantages for warehousing and movement by forklift trucks. Whilst there have been numerous designs of bulk fluid containers, they have generally been subject to compromises in their performance. For example, where the bulk containers have been formed of a polymeric material, the polymeric material may often be subject to bulging caused by the weight of the contents of the container. Over time this may become so serious that the container leaks or is no longer useable.

Some containers are unsuitable for long term storage of liquids such as wine or spirits because of characteristics such as too high or too low oxygen permeability.

Other disadvantages of some of the container designs include not being readily cleanable after each use and/or not allowing ready discharge of the contents under gravity. Some designs do not allow ready access for sampling of the container contents during maturation and/or are not stackable. International patent application number PCT/AU2014/000940 describes a container assembly which seeks to alleviate some of the problems listed above. However in practice it has been found to suffer problems with neck distortion over time which may result in leakage of contents. Also, it has been found that discharging of the container contents results in undesirable entrainment of air, an issue which is of major concern to wine makers. Additionally, the walls of the container have been found to be subject to bulging over time despite the use of reinforcing posts. The closure system used requires too much force to effect a seal and can result in a sealing gasket being dislodged when the closure is opened. Expansion of the container contents with temperature change can cause leakage and the construction of the assembly base has been found to lead to the stirrups or hoops of the base frame being damaged by forklift tynes because they are not readily visible when containers are stacked.

The current invention seeks to provide a container construction which seeks to improve at least one of the above identified drawbacks.

Disclosure of the Invention

The invention provides, in one aspect, a bulk fluid container assembly comprising, a container formed of polymeric material having a bottom panel, a top panel and a side wall extending between and joining the bottom and top panels, an open-mouthed neck provided on the top panel, a drainage opening, and a closure assembly for sealing the container, wherein the top panel is shaped to direct air contained within the container to flow out of the open-mouthed neck as the container is filled with liquid, the bottom panel is shaped to direct fluid to flow under gravity towards the drainage opening when the container assembly stands on level ground, and the closure assembly comprises a locking ring cooperable with complementary locking means on the open-mouthed neck to push upon a top face of a lid interposed between the locking ring and neck to bear upon a sealing element interposed between an undersurface of the lid and a sealing surface of the neck whereby rotation of the locking ring with respect to the neck causes compression of the sealing element between the undersurface and sealing surface. The construction is such that neither surface rotates with respect to the sealing element during rotation of the locking ring to seal the container.

The polymeric material may comprise polyethylene. It may comprise high density, medium density or low density polyethylene. Preferably it comprises low density polyethylene. The container may be moulded using a rotational moulding process. Suitably, the container has a capacity of 600 litres to 20,000 litres. In one preferred form, the container assembly may have a footprint substantially the same as a standard pallet. The container may have a capacity of between 800 litres and 4000 litres, more preferably 800 litres and 1,200 litres.

The container may be generally cubic. The sides of the container may be reinforced with posts. The posts may be located in recesses moulded in the comer regions of the sides. Suitably, the recesses allow the side posts to fit snugly within them. The side posts may extend along recesses formed in the corner regions of the container.

The bottom panel of the container may be shaped so as to direct fluid to flow under gravity to a drainage opening when the container assembly stands on level ground. For this purpose, the drainage opening is suitably located at a substantially accessible central position. It may be recessed with respect to a wall so as to form protection for a tap fitted to the drainage opening. It may be located in a sump formed in the bottom panel of the container.

The separate base may comprise a moulded support base and a base frame. The moulded base may have an upper surface which is sloped and substantially conforms to the contours of the bottom panel of the container. It may have a lower surface with recesses for receiving the individual members of the base frame. It may be formed with openings for entry of the tynes of a forklift. The base frame may have tubular legs for telescopically receiving the bottom ends of the posts. The base frame may include stirrups aligned with the openings for tyne entry.

Suitably, side supports extend between and are joined to the posts. The side supports may be located in a perimeter recess formed in each side wall. The side supports can act to prevent bulging of the side walls.

The lid and neck may be formed in such a fashion as to allow the container to be accessed by two different sizes of openings. A first opening having a diameter of between 250 mm and 400 mm may be provided so that the interior of the container can be accessed by cleaning equipment. A second opening of smaller diameter may be provided in the lid to allow filling.

Shaping of the top of the container is suitably arranged to ensure that air flows towards the first opening in the top panel as the container is filled. For this purpose, the top of the container may be bulged or domed. It may include one or more ribs shaped to lend rigidity. They may help to direct air along the top to the first opening. Similarly, the lid may be domed to direct air to the smaller second opening as the container is filled. The sealing element may comprise a silicone gasket.

The second opening may be sealed with a closure or bung. The closure may incorporate a pressure relief valve. A tube may be arranged to direct fluid from the pressure relief valve to an overflow vessel. The overflow vessel may be located in a recess formed in the side wall.

A foot may be provided for each post. The foot may be adapted to sit upon the top of a corresponding post of another container assembly whereby to facilitate stackability of container assemblies.

A spacer may be interposed between each foot and corresponding post. Suitably the open-mouthed neck is integrally moulded with the container and includes an annular reinforcing ring.

Where the container assembly is used for maturation of wine or spirts, the container may comprise polyethylene. The thickness and surface area of the container can be set to provide that the oxygen transmission characteristics of the container give an oxygen transmission rate from air at standard temperature and pressure, into wine stored in the container of between 7 milligrams and 35 milligrams of oxygen per litre of wine per year.

Preferred aspects of the invention will now be described with reference to the accompanying drawings.

Brief Description of the Drawings

Figure 1 illustrates an axonometric view of a bulk fluid container assembly according to one aspect of the invention;

Figure 2 illustrates an alternative axonometric view taken looking upwards from the base of the container of Figure 1 ;

Figure 3 shows an exploded view of the container of Figure 1;

Figure 4 shows an exploded view of the neck and closure assembly of Figure 1;

Figure 5 shows a partial sectioned expanded view of the closure assembly of Figure 1;

Figure 6 shows an axonometric view of the container of Figure 3;

Figure 7 shows a plan view of the container of Figure 6; and

Figure 8 shows a cross-section taken through the container assembly of Figure 1.

Detailed Description of the Preferred Embodiments

The various elements identified by numerals in the drawings are listed in the following integer list. Integer List

1 Bulk fluid container assembly

3 Container

5 Base frame

7 Support base

11 Closure assembly

13 Post

14 Foot

15 Spacer

16 Side support

20 Neck

21 Lug

22 Open mouth

23 Annular reinforcing ring

24 Sealing element

26 Lid

28 Locking ring

30 Complementary lug element

31 Joining ring portion

33 Skirt portion

34 Opening

36 Sealing surface

37 Sealing surface

38 comer recess

40 Side wall

42 top panel

44 Bottom panel

46 Sump

48 Drainage opening

50 Moulded rib

52 Perimeter recess 54 Recess

56 Sample tap socket

58 Cross bar

60 Side bar

63 Stirrup

64 Foot

66 Openings

67 Foot

68 Sloping bottom

69 Drainage hole

70 Ribbed girdle

Referring to Figures 1, 2 and 3 there is shown a fluid container assembly 1 according to one aspect of the invention, comprising a container 3 which may suitably be moulded of a polymeric material. The polymeric material may be polyethylene, preferably low-density polyethylene, although high density or medium density polyethylene may be used depending on the characteristics needed in relation to the nature of fluids held in the container. It may be produced by rotational moulding, injection moulding or blow moulding. As a particularly preferred use is in relation to a base size comparable with standard sized pallets, it may typically have a capacity of 800 to 4000 litres, more preferably 800 to 1200 litres. However for certain applications a broader range of sizes from 600 to 10,000 or even 20,000 litres may be applicable.

For example, if the container is to be used to mature wine, the thickness of the container, based on the use of high, medium or low density polyethylene, needs to be chosen to adjust the oxygen permeation rate of the container so as to give a rate of permeation similar to that achievable during maturation of wine in oak barrels, ie. the rate of oxygen permeation should be similar to that achievable with oak barrels having a range from 600 litres to 20,000 litres. This may equate to an oxygen permeation rate which lies between 7 and 35 mg of oxygen per litre per year at standard temperature and pressure. Where this is a requirement, in instances where the primary container is formed by rotational moulding of polyethylene, applicants find that a thickness of container in excess of 4* mm for containers ranging between 600 and 20,000 litres may be required to achieve satisfactory maturation of wine comparable with that achievable with oak barrels. Similar characteristics may be required where spirts such as whisky are being matured.

Whilst some of the foregoing discussion deals with a specific application for the container, namely wine, it is to be appreciated that the container may be used for a range of different fluids, some of which do not require the oxygen permeation storage conditions required for maturation of wine. This is particularly the case where the container is being used for short term storage or with other liquids such as spirits, oils, water, etc.

The container 3 is mounted on a base frame 5 which fits beneath a support base 7. The support base is suitably moulded from polymeric material. It is shaped with recesses so as to snugly fit over the bars of the base frame and also shaped to receive the bottom of the container 3. As the bottom of the container 3 bulges outwardly and slopes the support base 7 also slopes and supports bottom panel 44 of the container 3. As seen more clearly in Figure 8 the bottom of the moulded support base has a slope corresponding to that of the container.

The container 3 and is configured so that the posts 13 protrude through the tubular legs 62 of the base frame and extend along corner recesses 38 as shown more clearly in Figure 6.

A closure assembly 11 is provided to seal off the open container mouth 22 provided on top of the container 3.

Each of the posts 13 is provided with a foot 14. The bottom of the foot, as shown in Figure 3, is shaped so as to receive the top of a comer post 13 of a similar fluid container assembly upon which the fluid container assembly may be mounted or stacked. Alternatively a spacer 15 (shown in Figure 1) may be optionally provided for each comer post. It is shaped so as to fit into the top of each post and into the bottom of each foot 14. The use of spacers for stacked assemblies allows access to the closure assemblies without requiring dismantling of the stacks.

A perimeter recess 52 is provided to receive the side supports 16.

The posts 13 are adapted to fit within the corner recesses 29 and are joined to the side supports 16. Both the posts and side supports 16 serve to reinforce the container 3 against bulging of the container 3 when it is filled with fluid.

The base frame 5 is provided with tubular legs 62 through which the posts 13 may telescopically slide.

A drainage tap (not shown) can be fitted to the drainage opening 48 provided in the sump 46.

A recess 54 is provided in the side wall 40. The recess 54 includes a sample tap socket 56 and provides a housing for an overflow container (not shown) if required.

Referring to Figures 5, 6 and 7, it can be seen that the container 3 shown as a component of the fluid container assembly 1 in the earlier drawings, has side walls 40 integrally moulded with the perimeter recess 52. The recess has the dual function of providing a housing for the side supports 16 as well as increasing the overall surface area of the container and hence the oxygen transmission characteristics of the container. Varying the area of the recess can be used as a method of varying oxygen transmission.

The bulging and slope of the bottom panel 44 supported by the moulded base 7, apart from serving to distribute the load in the container across the base, also serves to facilitate drainage of fluid from the container. The slope directs drainage across the bottom panel towards the sump 46. The sump has a drainage opening 48 which can act as a socket for a drainage tap (not shown). The sump is recessed with respect to the side panel 40 to reduce risk of accidental damage. By having a sump, the risk of air being entrained with liquid drained from the container when it is nearly empty is reduced.

The top panel 42 of the container 3 is provided with moulded ribs 50 shaped to increase the stiffness of the top and to maintain a domed top panel whereby to assist with purging of air when the container is filled with liquid. This is particularly important where the contents of the container are such that they should be protected from spoilage by oxygen especially if the container is used to mature wine. Whilst this embodiment shows five ribs, it is to be appreciated that more or fewer ribs can be used, depending on the thickness and strength of the polyethylene forming the top panel of the container and the overall dimensions and capacity of the container.

The container neck has a mouth which may typically have a diameter of 250 mm to 400 mm to allow access for cleaning devices to the container interior. A diameter of 325 mm to 375 mm is preferred.

The container neck is integrally formed with the body of the container during moulding to avoid the need for an extra seal which would be required if the neck were to be added as a separate component. To ensure rigidity of the neck an annular reinforcing ring 23 is incorporated in the neck during the moulding process. Where a rotational moulding process has been used, the ring 23, suitably of stainless steel, may be held in place by a plurality of screws secured to the mould during moulding. These are unscrewed when moulding is completed, leaving a number of screw holes 25 as shown more clearly in Figure 7. These holes may be subsequently filled in with a resin after the container has been removed from the mould.

A number of integrally formed lugs 21 are provided around the outer perimeter of the neck to provide means for locking the closure assembly to the neck.

The neck terminates in a sealing surface 37 surrounding the open mouth 22. Referring to Figures 2 and 3, the base frame 5 comprises a plurality of cross bars 58 which may be formed of steel or any strong material joined to a pair of side bars 60. The side bars are in turn fixed to tubular legs 62 which are adapted to receive the posts 13. The cross bars are provided with stirrups or hoops 63 for receiving the tynes of a forklift. The hoops facilitate tilting and lifting of the container by a forklift.

Referring to Figure 8, the support base 7 is provided with a floor having holes 69 to help to allow drainage if necessary. The floor has a sloping bottom 68 which matches the slope of the bottom panel 44 of the container.

At the comers of the support base 7, there are comer openings extending completely through the support base 7 to allow penetration by the posts 13 and associated tubular legs 62. Each comer of the support base has a foot 64. An additional centrally located foot 67 is provided on opposite sides to define openings 66. These serve to guide the tynes of a forklift into correct alignment beneath the container assembly. The foot 64 is omitted on the adjacent sides to facilitate placement of a pallet jack through these sides. The sides of the support base incorporate a ribbed girdle 70 to allow air circulation.

Referring to Figures 4 and 5, the closure assembly 11 comprises a lid 26, sealing element 24 and locking ring 28.

The lid 26 is formed of a moulded plastics material having a domed undersurface shaped to allow air to escape through the opening 34 as the container is filled. The internal surface surrounding the opening 34 is screw threaded to allow a bung (not shown) to be screwed thereinto to seal the container after filling. The bung may be substituted by a closure (not shown) having a pressure relief valve. A tube for allowing drainage of liquid may be provided to direct overflow liquid into an overflow container (not shown).

The undersurface of the lid is provided with a sealing surface 36. The locking ring 28 is also formed of moulded polymeric material and comprises a joining ring portion 31 and a skirt portion 33.

A plurality of complementary lug elements 30 connect the joining ring portion and skirt portion. The bottom portions of the complementary lug elements 30 are shaped to underlie the lugs 21 of the neck 20 when the locking ring is pressed down on the lid and neck and twisted. The lugs 21 and/or 30 may be slightly ramped so that the twisting action presses the locking ring onto the lid 26 whereby to bear down upon and compress the sealing element 32 between the sealing surfaces 36 and 37.

As the lid does not rotate with respect to the sealing element when the locking ring is applied the sealing element is not subjected to transverse distortion when the lid is applied to seal the container. As the locking ring and lid are made of harder plastics than the soft sealing element, rotation of the locking ring over the lid does not require extreme force.

The construction of the closure assembly is such that the container 3 can be accessed for filling through the relatively narrow opening 34 when the plug is removed. When access to the interior of the container 3 is required for purposes such as cleaning, the locking ring and lid may be removed to expose the wide-open mouth 22. Suitably the open mouth 22 is at least twice as large as the opening 34.

Whilst the above description includes the preferred embodiments of the invention, it is to be understood that many variations, alterations, modifications and/or additions may be introduced into the constructions and arrangements of parts previously described without departing from the essential features or the spirit or ambit of the invention.

It will be also understood that where the word “comprise”, and variations such as “comprises” and “comprising”, are used in this specification, unless the context requires otherwise such use is intended to imply the inclusion of a stated feature or features but is not to be taken as excluding the presence of other feature or features. The reference to any prior art in this specification is not, and should not be taken as, an acknowledgment or any form of suggestion that such prior art forms part of the common general knowledge.