GB2163733A

GB2163733A - Tamperproof seal

Info

Publication number: GB2163733A
Application number: GB08520362A
Authority: GB
Inventors: Finlay Miller
Original assignee: Scottish and Newcastle Breweries PLC
Current assignee: Heineken UK Ltd
Priority date: 1984-08-14
Filing date: 1985-08-14
Publication date: 1986-03-05
Also published as: GB8520362D0; GB2163733B

Abstract

A sealing material is sprayed around the extractor head 1 of a beer keg 5 and extending over onto the Barnes neck 4 to ensure that the extractor cannot be removed without detection. A masking device 10, 30 (Fig. 8 not shown) is provided to ensure that the sealing material does not enter the centre hole of the extractor head. A self adhesive label 2 is then placed over the centre hole on the extractor head. <IMAGE>

Description

SPECIFICATION Tamperproof seal This invention relates to a method of and to apparatus for applying a tamperproof seal to containers such as for example beer kegs.

Beer kegs have closure members or extractor heads which are screwed into an opening in the main body of the container. The extractor has valve means to allow the extraction of beer from the keg. It is a requirement that the extractor device and valve means should be provided with a tamperproof seal to prevent unauthorised opening of the keg. However, as the extractor device need not be removed each time the keg is re-used it is wasteful if the seal between the extractor device and the keg is broken each time the valve seal is opened.

According to the present invention there is provided a method of applying a seal to a closure member of a beer keg comprising spraying a sealing material to said closure member of the keg to seal said closure member to said keg, masking means being provided to prevent said sealing material from covering valve means of said closure member.

Preferably, label means are affixed over the valve means.

Preferably also, sealing material is applied over the label means.

Preferably also, the sealing material is a low melting point thermoplastics material, a water based PVC material or a solvent based material.

Preferably also, the sealing material is applied by a movable sprayhead.

Further according to the present invention there is provided apparatus for applying a seal to a closure member of a beer keg, comprising a device for spraying a sealing material to the closure member of the beer keg to seal the closure member to the keg wherein a masking device is provided between the spraying device and the keg to prevent the sealing material from covering valve means of the closure member.

Preferably, a device is provided to place a label over the valve means of the closure member.

Most preferabiy, the label is of paper material and is semi-perforated and self-adhesive.

Preferably also, a device is provided for spraying sealing material over the label.

The sealing material may be a low melting point thermoplastic material, a water based PVC material or a solvent based material.

Preferably, the sealing material is applied by a movable sprayhead or by moving the keg below a fixed sprayhead.

Embodiments of the present invention will now be described, by way of example, with reference to the accompanying drawings, in which: Figs. 1 to 6 are perspective views of a beer keg extractor head showing respectively: the extractor head fully tightened down ready for sealing; the extractor head with a sealing material applied in accordance with the present invention; the extractor head with a sealing material and label applied; the extractor head in the condition as received by the customer with the sealing material and label intact; the extractor head showing the label being removed; the extractor head being attached to a coupler for the legitimate removal of beer; Fig. 7 is a perspective view of a first embodiment of a machine for applying a seal to a keg in accordance with the present invention; Fig. 8 is a sectional front elevation of a second embodiment of a machine for applying a seal to a keg in accordance with the present invention; Fig. 9 is a plan view of the machine of Fig.

8 taken along the line AA; Fig. 10 is a partial plan view of the machine of Fig. 8 taken along the line BB; Fig. 11 is a sectional side view of the machine of Fig. 8 taken along the line CC; and Fig. 12 is a perspective view of a beer keg extractor with a second embodiment of a seal applied in accordance with the present invention.

Referring to Figs. 1 to 6, a beer keg has a closure member in the form of an extractor head 1 which is to be sealed in accordance with the invention. The extractor head is first fully tightened on to the keg as in Fig. 1.

A plastics material seal 3 is applied to the extractor head 1 and extends over on to the Barnes neck 4, this ensures that the extractor cannot be removed without detection.

The keg with the extractor head 1 in this condition is then presented to the racking machine, washed and filled, and then passed through a labelling or covering machine which places a semi-perforated, self-adhesive label 2 over the centre hole on the extractor head 1.

When the customer receives the keg he ensures that the seal 3 and the label 2 are intact. The customer then removes the label 2 which being perforated cannot be replaced without detection.

A coupler 8 can then be placed over the extractor head 1 for the legitimate removal of beer.

Referring now to Fig. 7, this shows apparatus for applying the seal of Fig. 1. A line of kegs 5 enter the machine in the direction of arrow 6 and are halted by a keg escapement gear 7. The kegs 5 are then released by the gear 7 at timed intervals and then enter the main part of the machine to be pushed by a keg lift 9 upwards so that the extractor head 1 protrudes through a hole in a masking device 10 positioned below a rotating sprayhead 11 driven by a motor 12. The sprayhead 11 is supplied with the liquid plastics material 3 via pipelines 13 from supply tanks 14 which are pressurised by an air supply 15. The rotatable sprayhead 11 applies the plastics material 3 in liquid form around the extractor head 1 of the keg 5.After application of the plastics material 3 the keg 5 is lowered by the keg lift 9 and then passes beneath a heater 16 which dries the plastics material 3 so that it solidifies to form a seal around the extraction head 1 of the keg 5. The sealed keg 5 then leaves the machine in the direction of arrow 17 and is then ready for washing and filling. A cleaning device 18 is also provided to clean the masking device 10 and prevent a build-up of the plastics material 3.

Figs. 8 to 11 show a second embodiment of apparatus for applying the seal of Fig. 1.

Kegs 5 travel along a conveyor 20 and come to rest above a drive plate 21 within the main structure 22 of the spraying machine The keg 5 is then centralised on the drive plate 21 by centralising apparatus 23.

The centralising apparatus comprises four centralising arms 24 which are pivotally mounted on the main structure 22 at 25. Each arm 24 has a keg contact roller 26 at one end and is connected to a hydraulic slave cylinder 27 at the other end. The slave cylinders 27 are connected in a closed hydraulic loop circuit which is pressurised by a pneumatic control cylinder 28.

When the centralising apparatus 23 is actuated the control cylinder 28 operates to pressurise the slave cylinders 27. Each slave cylinder 27 pivots inwardly around its mounting point 25 by an equal amount so that each contact roller 26 contacts the keg 5 in turn and causes the keg to move towards a central position on the drive plate 21.

A lifting cylinder 29 then lifts the drive plate 21 and the keg 5 and brings it into contact with a rotatable spraying mask 30 and a spring loaded centre location mask 31 which form part of spraying apparatus 32.

An air' motor 33, which rotates the drive plate 21, is then operated simultaneously with sealing material spray nozzles 34. The keg rotates between the spray nozzles 34 and an even coat of sealing material is thus applied to the extractor head 1 of the keg 5.

After application of the sealing material the keg 5 is lowered by the lifting cylinder 29 and then exits from the machine along the conveyor 20.

The seal is semi-permanent and is only removed when it is damaged accidentally or when the keg extractor is being overhauled.

As the plastics material can be made in many colours it can act as a dating code for keg inspection. The plastics material is of such a thickness as not to interfere with the slipping on of the coupler and is of sufficient toughness to withstand many applications of the coupler.

An advantage of the semi-permanent nature of the seal is that the apparatus for sealing the kegs need not be incorporated in the keg filling production lines but may instead be positioned in a keg assembly area. This is because the seal need not be replaced every time the keg is filled but only when inspection on return of the empty kegs shows a seal to be damaged.

There are a number of advantages of this type of seal. It provides an adequate dust cover over the extractor head. It can be used for quality identification and for keg age inspection. The seal cannot be resealed after it has been broken. The perforated label or shrink cover prevents broaching of the keg by someone in possession of an illicit coupler.

As the seal has to be broken to allow removal of the extractor it prevents theft and adulteration of the beer either on route to the customer or by the customer himself.

When paper labels using a water based glue are used there is the possibility that, not being waterproof, the label may be washed off by rain if the keg stands outside prior to delivery. To overcome this the paper label 2 may be oversprayed with a small quantity of plastics sealing material 35 to waterproof it, as illustrated in Fig. 1 2. The label 2 in this case is provided with small tear tabs 2a. A mask is arranged between the spraying apparatus and the label so that the plastics sealing material 35 does not cover the tear tabs 2a.

The customer then uses the tear tabs 2a to remove the label 2 and sealing material 35.

Modifications and improvements may be incorporated without departing from the scope of the invention.

Claims

1. A method of applying a seal to a closure member of a beer keg comprising spraying a sealing material to said closure member of the keg to seal said closure member to said keg, masking means being provided to prevent said sealing material from covering valve means of said closure member.

2. A method of applying a seal to a closure member of a beer keg as claimed in Claim 1, wherein label means are affixed over the valve means.

3. A method of applying a seal to a closure member of a beer keg as claimed in Claim 2, wherein sealing material is applied over the label means,

4. A method of applying a seal to a closure member of a beer keg as claimed in Claim 1, 2 or 3, wherein the sealing material is a low melting point thermoplastics material.

5. A method of applying a seal to a closure member of a beer keg as claimed in Claim 1, 2 or 3, wherein the sealing material is a water based PVC material.

6. A method of applying a seal to a closure member of a beer keg as claimed in Claim 1, 2 or 3, wherein the sealing material is a sol vent based material.

7. Apparatus for applying a seal to a closure member of a beer keg comprising a device for spraying a sealing material to the closure member of the beer keg to seal the closure member to the keg wherein a masking device is provided between the spraying device and the keg to prevent the sealing material from covering valve means of the closure member.

8. Apparatus for applying a seal to a closure member of a beer keg as claimed in Claim 7, wherein a device is provided to place a label'rover the valve means of the closure member.

9. Apparatus for applying a seal to a closure member of a beer keg as claimed in Claim 8, wherein the label is of paper material and is semi-perforated and self-adhesive.

10. Apparatus for applying a seal to a closure member of a beer keg as claimed in Claim 8 or 9, wherein a device is provided for spraying sealing material over the label.

11. Apparatus for applying a seal to a closure member of a beer keg as claimed in any one of Claims 7 to 10, wherein the sealing material is a low melting point thermoplastic material.

12. Apparatus for applying a seal to a closure member of a beer keg as claimed in any one of Claims 7 to 10, wherein the sealing material is a water based PVC material.

13. Apparatus for applying a seal to a closure member of a beer keg as claimed in any one of Claims 7 to 10, wherein the sealing material is a solvent based material.

14. Apparatus for applying a seal to a closure member of a beer keg as claimed in any one of Claims 7 to 13, wherein the sealing material is applied by a movable sprayhead.

15. Apparatus for applying a seal to a closure member of a beer keg as claimed in any one of Claims 7 to 13, wherein the sealing material is applied by moving the keg below a fixed sprayhead.

16. A method of applying a seal to a closure member of a beer keg substantially as hereinbefore described with reference to the accompanying drawings.

17. Apparatus for applying a seal to a closure member of a beer keg substantially as hereinbefore described with reference to the accompanying drawings.