GB2244265A - Vessel sealing device - Google Patents

Abstract

A device (1) for sealing a vessel such as a plastic beer keg and preferably connected to the neck of a beer keg by crimping comprises a cap (10) with a hole sealable by a stopper displaceable to a first position from which it may return to seal the hole, or to a second position from which it may not return to seal the hole. Preferably two stoppers 2, 3 are provided to seal holes 5D and 5A, B respectively and are mounted abutting one another such that an axial force on stopper 3 to unseal the vessel is capable of displacing both stoppers and a force exerted on stopper 2 displaces only that stopper. <IMAGE>

Description

A SEALING DEVICE This invention relates to a sealing device and more specifically, but not exclusively, to a device for sealing vessels containing liquids, such as a beer keg.

A problem with beer kegs in the past has been the considerable expense required to return the beer kegs when empty. Aluminium beer kegs, even when empty, are still very heavy and require large trailers to transport them in bulk. In the past the economic advantages of using aluminium beer kegs have outweighed the disadvantages. This is because aluminium beer kegs, despite being heavy, are robust and have a relatively long life. However, this economic decision has been based on the assumption that beer kegs have only ever been distributed within a small region and thus transport costs have been relatively small.

The current trend of reduced restrictions in trade barriers makes the possibility of importing and exporting beer more attractive. However, the problem still remains of how to return empty barrels or kegs.

This problem has to some extent been alleviated by the introduction of disposable containers or kegs, so that a transporter may carry full kegs on an outward journey and perhaps a different load on a return journey, thus halving the overheads of transport costs.

Manufacturers of such disposable containers are understandably very keen to ensure that their containers are used only once and may not be refilled.

This is also desirable from a point of view of safety and hygiene.

According to a first aspect of the present invention there is provided a sealing device for sealing a vessel comprising a cap having at least one hole in it, the cap having a stopper which is adapted to seal the or each hole, the stopper being displacable to one of two positions, the first position being one from which the stopper may return to seal the or each hole, the second position being one from which the stopper may not return to seal the or each hole.

According to a second aspect of the present invention there is provided a sealing device for sealing a vessel comprising a cap having a first and second hole, and a first and second stopper for respectively sealing said first and second holes, the first stopper being mounted on a resiliently deformable member and the stoppers abutting one another in such a manner that an axial force exerted on the first stopper in order to unseal the vessel, is capable of displacing both stoppers, and a force exerted only on the second stopper displaces only the second stopper.

Preferably, the second stopper is mounted on a deformable member such that when the second stopper is displaced to a position in which the second hole is open, the second stopper may not return to re-seal the second hole.

The cap may be formed from a synthetic plastics material which may be injection moulded.

Stoppers are mounted on an upper and a lower support within the cap. Preferably the two supports engage with one another within the cap by way of interlocking splines in grooves.

Preferably the cap is cylindrical and has four holes. Three of these holes are sealed by three separate plugs mounted on the upper support to form the first stopper, the fourth hole being sealed by a single plug mounted on the lower support.

Although reference has been made to beer within a beer keg, clearly the invention may be employed as a sealing device for a vessel for containing any liquid in disposable containers. Such liquids may include, fruit juices, milk or oils.

Embodiments of the invention will now be described by way of two examples only, and with reference to the Figures in which: Figure 1 is a longitudinal section of one embodiment through a sealing device as mounted on a keg; Figure 2 is a plan view of the cap of Figure 1; Figure 3 is an elevation of a deformable stopper; Figure 4 is a plan view of Figure 3; Figure 5 is an elevation of the resiliently deformable stopper; Figure 6 is a plan view of the resiliently deformable stopper of Figure 5; Figure 7 is a longitudinal section of an alternative embodiment of a reliable device; and Figure 8 is a transverse section of Figure 7.

Referring to Figure 1, which shows a sectional view of a sealing device 1 as being in the form of a right-circular cylinder. The sealing device 1 consists of three portions, an upper support 3 and a lower support 2 disposed within a cylindrical cap 10. The lower support 2 abuts the upper support 3 by way of extended tongue 3C. The cap 10 is attached to a vessel 4, of which only part is shown, by crimping or by bonding its periphery around the rim of the vessel's neck 4A. The cap 10 can, in this way, only be attached once to a vessel, and it is impossible to remove the cap, without damaging the neck 4A of the vessel 4. The cap 10 has four holes 5 drilled through its upper surface 11. A standard adaptor (not shown) may be attached to the top of the cap to the keg. The CO2 is used to forcebeer from the keg. For example to connect a CO2 bottle.Usually the central hole 5D accepts a dispensing tube and CO2 is pumped in through the other three holes. The holes 5 may be formed integrably with the cap 10 at an injection moulding stage, and may be provided with a suitable thread for such adaptors. On the lower, surface of the cap 10, the holes 5 are countersunk, and a seal 6 is disposed within each of these recesses so as to prevent leakage of the fluid when the vessel is full. These seals may be suitably sized rubber grommets.

The lower support 2 and the upper support 3 have three limbs 2A, 2B and 2C and 3A, 3B and 3C respectively. The portions 2 and 3 support stoppers for sealing the vessel 4, as described below.

Figure 3 shows the lower support 2 in elevation and, Figure 4 shows the lower support 2 in plan, as removed from the cap 10. Thz lower support 2 consists of a solid cylindrical stopped 20 through which four holes 21, 22, 23 and 24 have be-n drilled. A long reach tube (not shown) is attacheS to the stopper 20, through which beer may flow. In addition the cylinder is splined and has three limbs 2A, 2 and 2C disposed at 120C to one another. The limbs 2A, 2t and 2C lie substantially flat when unflexed becaus they are made from a resiliently deformable synthetic ç as tics material. The limbs 2 may be fitted to the stopper 20 by way of a collar or may be formed from a single moulding with the stopper. The cylindrical stopper 20 has a stepped portion 25 which abuts the upper support 3.

Figures 5 and 6 show elevation and plan views o the upper support 3 respectively. The upper support 3 consists of three plugs 30A, 30B and 30C. Each plug has four holes 31, 32, 33 and 34 drilled therethrough.

These holes 31, 32, 33 and 34 are in an offset disposition with respect to the holes 5 in the cap 10, so that when the upper support 3 abuts the upper inner surface of the cap 10, the vessel 4 is sealed. When the upper support 3 is displaced downwards, in the manner hereafter disclosed, fluid may enter or leave the vessel by passing through the holes 21, 22, 23 and 24 in the lower portion and out of the cap 10 via the central hole 5D in its upper surface 11. The fluid is forced out of the vessel 4 under pressure by the CO2, which enters via holes 5A, 5B and 5C in the cap. The upper support 3 has a suitably shaped central aperture 36, to receive the splined cylindrical stopper 20.

This prevents the lower support 2 from rotating with respect to the upper support.

The sealing device 1 is assembled firstly by sliding the upper support 3 inside the cap 10 and then sliding the lower support 2 into the cap 10 so that the splined cylindrical portion 20 is male to the aperture 36 of the upper support 3. Both supports are then permanently disposed within the cap 10. This may be achieved by having tongue and groove fittings on the limbs and on the inner walls of the cap, or by bonding the supports onto the walls of the cap, with heat or a suitable adhesive. Alternatively a thread may be cut so that the lower support 2 screws into the cap and "traps" the upper support 3.

The cap will now be described, with reference to the Figures, in its mode of operation.

The cap will be described firstly with reference to filling the vessel 4, then as sealed so that the vessel may be transported, and then as a non-resealable device.

The vessel 4 is filled by forcing the upper support 2 in the direction of the arrow on Figure 1 for example by utilising the fluid pressure of the filling liquid. This urges the lower support 2 downwards so that the vessel 4 may be filled. The limbs 3A, 3B and 3C of the upper support 3 flex, but the movement is not sufficient to cause the limbs 3A, 3B and 3C to move "over centre". The limbs of the lower support 2, correspondingly do not flex past the "over centre position".

When the vessel is full the force, be it mechanical or the fluid pressure aforesaid, is removed, the limbs of the upper and lower supports are permitted to return to their initial position, such that the upper and lower supports abut one another and the upper support 3 abuts the upper surface of the cap 10 thereby sealing it and the vessel. The vessel thus sealed may be transported.

Alternatively the cap may be fitted to a vessel or keg by crimping or bonding the cap around the neck of the keg after it has been filled.

In order to open the vessel 4, a suitably adapted device is fitted to the cap. This may be a standard adaptor which has a CO2 supply. The CO2 is then used to force the lower support 2 downwards, beyond the over centre position of the limbs 2A, 2B and 2C, so that the limbs 3A, 3B and 3C are either permanently broken and/or plastically deformed, thus allowing CO2 to enter. A dispensing tube (not shown) is attached to the adaptor and has a seal which surrounds hole 5D so that it receives the liquid under pressure. The CO2 thus forces out the stored liquid. Of course another gas may be used. The gas is delivered via the holes 5A, 5B and 5C, whilst the liquid is pumped out via hole 5D.

The beer keg may be inverted, and therefore no long reach tube is required as beer will be "above" the hole 5D and will flow out of the keg under the pressure of the CO2. Once the keg itself is empty the cap may not be used again as the upper support 3 has been deflected to such a degree that the stoppers 30A, 30B and 30C are no longer in contact with the upper surface of the cap 10 and can therefore not seal holes 5A, 5B and 5C respectively. This may be achieved in practise by permanently deforming the limbs 3A, 3B and 3C of the upper support or by dislodging the support so that it falls into the cavity of the cap.

Figures 7 and 8 show sections of an alternative embodiment of the invention. A resealable cap 100 has a body 100A an upper portion 101 and a lower portion 102. The cap 100 is fixed to a beer keg 4, around the periphery of the neck 4A of the keg 4, by an adhesive or by crimping.

The lower portion 102 comprises a central cylindrical stopper 104 which has a channel 105 drilled along its length and slightly offset from its axis of symmetry. Attached to the lower portion 102 so that it is in fluid connection with channel 105 is a tube 106 (only part of which is shown).

Tube 106 reaches below the surface of liquid within the beer keg.

The lower portion 102 has three equi-angular spaced limbs 102A, 102B and 102C, of which only 102A is shown in section. The limbs 102A, 102B and 102C are fixed to the inner wall of the cap 100 by an adhesive.

The upper portion 101 comprises a unit having three cylindrical portions 107A, 107B and 107C. These cylindrical portions are mounted onto a central ring 121 by way of limbs 101A, 101B and 101C. The limbs 101A, 101B and 101C are linked to a central ring 121.

The complete arrangement may be formed from a single injection mould. Limb 101A, 101B and 101C of the upper portion 101 when inserted into the body of the sealing cap 100 may be bonded to the inner walls of the cap.

Alternatively the upper portion 101 may be held in position by the lower portion 102 by locking the upper portion 101 in place by the limbs of the lower portion.

Each of the three cylindrical portions 107 of the upper portion 101 have a channel 114 drilled axially through them. The cylinders 107 are free to move axially within three respective cavities 110. The cavities 110 are integrably formed within the body 100A of the resealable cap 100. When the cylinders 107 move axially all three limbs 101A, 101B and lQlC flex. A channel 109 connects each of the cavities 110 to a main cavity 111. The main cavity 111 is rebated below the upper outer surface of the cap 100. The rebated cavity is suitably sized to enable a universal adaptor to be connected to the cap and, by way of splines, the universal adaptor may be locked into the central cavity. The cap 100 itself, because of its relatively intricate recesses, rebates and internal features, is moulded. Channels 109 and 190 may be drilled at a later stage. When sliding cylindrical portions 107A, 107B and 107C abut the upper inner surfaces of the locating cavities 110 the channels 114 in each of the cylindrical portions 110 lie offset to respective channels 190 so that all the channels remain sealed.

suitable seal, such as a rubber O-ring seal 130, is arranged around the central cylindrical stopper 104.

A second rubber O-ring seal 131 is positioned so that it seals he cap when the lower portion 102 abuts against it.

The unassembled cap 100 comprises a main moulded body 100A, a lower portion 102, an upper portion 101 and two O-ring seals 131 and 132. The upper portion 101 is inserted into the body of the cap such that the first O-ring seal 131 rests between it and the body 100A of the cap. The second O-ring seal 130 is disposed within the recessed groove 132 and the lower portion. The lower portion 102 is then inserted into the body 100A of the cap 100 and twisted so that the lower portion locks by way of splines 200 into grooves in the upper portion. The limbs of the lower portion 102 may then be bonded onto the inner wall of the cap by way of an adhesive or by use of heat.

The cap 100 thus assembled will now be briefly described in its mode of use. The resealable cap 100 assembled, as described above, is permanently attached to the neck of a vessel or keg 4. The vessel or keg 4 is already full of beer and the cap 100 has a long reach tube 106 attached to the lower portion 102 which passes into the keg so that all or substantially all the beer may be forced from the keg 4 by a forcing fluid such as CO2. The keg 4 may thus be transported.

When it is desired to open the keg 4 a suitable adaptor (not shown) is connected to the top of the cap 100 and which pushes down the lower portion 102 by way of a plunger 127 which because the lower portion and the upper portion 101 are interlocked pushes the lower portion down as well, either breaking or permanently deforming limbs 101A, 101B, 101C on removing adaptor limbs 102A, 102B, 102C will return to original position allowing 102, 104 to re-seal. Cylinders 107A, 107B and 107C which are supported on limbs 101A, 101B and 101C respectively are also forced downwards, but may return to their "sealing position'1 once the forcing pressure of the CO2 has been removed. Beer is thus forced up the tube 106 through plunger 127 and out along a delivery line (not shown) to a dispensing system. The sealing device may thus only be used once because it is impossible to fit a new device without damaging the vessel.

It will be appreciated of course that variation may be made to the above, without departing from the scope of the invention, in that for example four limbs may be used or a snap-action may be provided to the lower support such that once forced beyond a predetermined limit it may not return to re-seal the vessel.

Claims (12)

1. A sealing device for sealing a vessel comprises a cap having at least one hole in it, the cap having a stopper which is adapted to seal the or each hole, the stopper being displacable to one of two positions, the first position being one from which the stopper may return to seal the or each hole, the second position being one from which the stopper may not return to seal the or each hole.

2. A sealing device for sealing a vessel comprises a cap having a first and second hole, and a first and second stopper for respectively sealing first and second holes, the first stopper being mounted on a resiliently deformable member and the stoppers abutting one another in such a manner that an axial force exerted on the first stopper in order to unseal the vessel, is capable of displacing both stoppers, and a force exerted only on the second stopper displaces only the second stopper.

3. A sealing device according to claim 2 wherein the second stopper is mounted on a deformable member such that the second stopper may not return to re-seal the second hole.

4. A sealing device according to claims 1, 2 or 3 wherein the or each stopper comprises an elongate member having one or more channels therethrough the channel or channels'being such that when the or each member abuts an inner surface of the sealing device, sealing occurs by virtue that the or each channel is offset from the respective hole or holes in the sealing device.

5. A sealing device according to claim 3 wherein the members are cylindrical and are splined so as to permit relative axial displacement.

6. A sealing device according to any preceeding claim, which is connected to the neck of a vessel by crimping.

7. A sealing device according to any preceeding claim which comprises a cap, which is adapted to receive an adaptor for a fluid supply and exhaust line.

8. A sealing device according to claim 7 wherein the cap has means adapted to abut the adaptor so as to transmit an axial force to displace a stopper when in use.

9. A sealing device according to any preceeding claim wherein the or each stopper is supported by a supporting limb formed integrably with the or each stopper.

10. A sealing device according to claim 9 when dependant on claim 2 or 3 wherein three cylindrical members are supported by three limbs on the second stopper and the first stopper comprises a cylinder supported by three limbs.

11. A sealing device substantially as described with reference to figures 1 to 6.

12. A sealing device substantially as described with reference to figures 7 and 8.