Closure, and method and apparatus for attachment of a closure

Abstract

 Closure (1), method and apparatus for closing a packaging tube (2), the closure being provided with a recess (6) at each corner of a sidewall (3) thereof and the method comprising partially severing and then urging respective corner portions (2') of the tube into the recesses and thereby securing the closure to an end of the tube.

Description

[0001] The present invention relates to closures and in particular, but not exclusively, to closures suitable for attachment to an end of a packaging tube. The present invention also relates to a method and apparatus for attachment of a closure to an end of a tube.

[0002] Known packaging comprises a 'lay flat' packaging tube, typically made of a plastics material, which is closed at both ends by way of closures in the form of caps or plugs. One known way of attaching a closure to a tube comprises stapling the closure the tube. Despite the convenience of that method, injuries can result from a customer's skin being pierced by a free end of a staple if the staple is not correctly affixed and and/or when removing the staple.

[0003] The present invention seeks to provide an alternative closure, together with an alternative method and apparatus for attachment of a closure to a tube.

[0004] According to a first aspect of the invention there is provided a closure suitable for attachment to an end of a tube, the closure being provided with a recess in a sidewall, which recess is adapted to receive a depressed portion of the tube.

[0005] Preferably the recess is defined by a radially inwardly located sidewall portion.

[0006] Preferably the recess is bounded by upper and lower walls.

[0007] Where the closure is of substantially rectangular shape the recess is preferably provided at a corner of the closure. Most preferably a recess is provided at at least two corners of the closure.

[0008] The closure is preferably adapted to be a plug-fit into an end of the tube.

[0009] According to a second aspect of the invention there is provided a method of closing an end of a tube comprising urging a portion of the tube into a recess provided in a sidewall of a closure.

[0010] The method preferably comprises urging a portion of a corner of the tube into a respective recess of the closure.

[0011] The method preferably comprises deforming a portion of the tube into a respective recess.

[0012] Desirably the method comprises urging at least two portions of the tube into respective recesses.

[0013] Preferably the method comprises at least partially severing the tube at a position which is adjacent a portion of tube which is urged into a recess.

[0014] According to a third aspect of the invention there is provided apparatus for securing a closure to an end of a tube comprising die means which, in use, is adapted to urge a portion of the tube into a recess provided in a sidewall of the closure.

[0015] Preferably the die means comprises cutter means. The cutter means, in use, is preferably operative to cut or at least partially sever the tube at a position which is adjacent to that portion of the tube which is urged into the recess.

[0016] The die means preferably comprises an actuated die head.

[0017] In a highly preferred embodiment the die means crimps a portion of the tube into the recess.

[0018] According to a fourth aspect of the invention there is provided packaging which comprises a tube, at least one end of which is attached to a closure in accordance with the first aspect of the invention.

[0019] Various embodiments of the invention will now be described, by way of example only, with reference to the accompanying drawings in which:

Figure 1 is a perspective view of a closure being urged into an end of a tube,

Figure 2 is a perspective view of the closure inserted into the tube,

Figure 3 is a perspective view of corner portions of the tube having been urged into respective recesses in the closure,

Figure 4 is an end view of the tube and closure of Figure 2 which is positioned in a(schematically illustrated) assembly for attaching the closure to the tube,

Figure 5 is a side elevation of a die head of the assembly for attaching the closure to the tube,

Figure 6 is a plan view of the die head of Figure 5,

Figure 7 is a schematic cross-section on A-A of a die head moving towards the tube and the closure of Figure 4,

Figure 8 is a schematic cross-section on A-A subsequent to that of Figure 7 in which the die head is deforming a corner portion of the tube into a respective recess of the closure, and

Figure 9 is a schematic cross-section on A-A subsequent to that of Figure 8 in which the die head is withdrawn from the tube and the closure.

[0020] With reference to Figure 1, there is shown a closure 1, in the form of a plug, and a packaging tube 2 of flexible plastics material, the closure 1 being urged into an end of the tube 2.

[0021] The closure 1 is of substantially square outline, the closure comprising a sidewall 3 which is upstanding from a base 4 provided at an axially innermost end of the closure. The base 4 comprises four diagonal ribs 11 which serve to increase the strength of the base. Corner portions 5 of the sidewall 3 comprise two wall portions 7 perpendicular to each other which define respective inwardly located recesses 6. The axially outermost end of the closure 1 comprises a flange 8 which, when viewed in plan, extends beyond the 'footprint' of the closure at by the innermost end of said closure. Those portions of the flange 8 at the corners of the closure 1 define an axially outermost end of each recess 6, and an axially innermost end of each recess being defined by respective corner portions 10.

[0022] With reference to Figures 4, 5 and 6, an assembly for securing the closure 1 to the tube 2 will now be described.

[0023] The assembly for securing the closure 1 to the tube 2 comprises four die head assemblies 15, each die head assembly comprising a pneumatic cylinder 16, a piston 17 and a die head 18. With reference in particular to Figures 5 and 6, each die head comprises a body portion 19 and blade portion 20. The blade portion 20 is of chamfered cross-sectional profile and defines a cutting edge 21. The body portion 19 and the blade portion 20 define two sides which are arranged substantially perpendicular to each other and so form a pointed shape (as best seen in Figure 6).

[0024] The closure 1 is attached to the tube 2 in the following manner.

[0025] The closure 1 is urged into the tube 2, the flange 8 serving as stop means to prevent the closure being pushed too far into the tube. Figure 2 shows the closure 1 fully inserted into the tube 2.

[0026] Handling means (not shown) conveys the tube 2 and inserted closure 1 to a predetermined position relative to the four die head assemblies 15. Once in position the pneumatic cylinders 16 are activated so causing the die heads 18 and respective pistons 17 towards a respective corner of the tube 2 and the closure 1, as illustrated in Figure 7. The blade portion 20 of each die head 18 comes into contact with the tube 2 so as to pierce that portion of the tube. As each die head 18 progresses further the body portion 19 engages with the tube and urges a portion 2' of the tube 2 into the respective recess 6. Figure 8 shows the die head 18 at the full extent of movement into the recess 6.

[0027] The die head 18 is then withdrawn and, as also seen in Figure 9, portion 2' of the tube has been partially severed and deformed through substantially 180°. A frictional engagement between the portion 2' and the flange 8 on the one hand, and between the portion 2' the base portion 10 on the other hand, is effected. This frictional engagement ensures that the portion 2' is 'captured' in the recess 6 by what may be termed an interference fit and, as a result, does not inadvertently move or 'spring' out of the recess.

[0028] It will be appreciated that if the opposite end of the tube 2 is also to be closed with a closure 1, then the process described above is repeated or performed simultaneously by a second set of die head assemblies.

[0029] Advantageously, folds 20 of the tube 2 act as hinges which aid the process of deformation of the portions 2' into the recesses 6.

[0030] In an alternative embodiment at least one recess is provided not at a corner of the closure but, for example, is located substantially central of a side of the sidewall 3.

[0031] In yet a further embodiment at least one recess is provided by a through-hole in the sidewall into which tube material is urged.

[0032] It will be appreciated that alternative closures are possible which are of different outline, eg round, triangular or indeed any other shape.

[0033] It will also be appreciated that the blade portions 20 may not be chamfered, so as not to define cutting edges 21.

Claims

1. A closure (1) suitable for attachment to an end of a tube (2), the closure being provided with a recess (6) in a sidewall (3), which recess is adapted to receive a depressed portion (2') of the tube.

2. A closure (1) as claimed in claim 1 in which the recess (6) is defined by a radially inwardly located sidewall portion (7).

3. A closure (1) as claimed in claim 1 or claim 2 in which the recess (6) is bounded by upper and lower walls (8, 10).

4. A closure (1) as claimed in any preceding claim in which the closure is of substantially rectangular shape and the recess (6) is provided at a corner of the closure.

5. A closure (1) as claimed in any preceding claim in which a recess (6) is provided at at least two corners of the closure.

6. A closure (1) as claimed in any preceding claim in which the closure is adapted to be a plug-fit into an end of the tube (2).

7. A method of closing an end of a tube (2) comprising urging a portion of the tube (2') into a recess (6) provided in a sidewall (3) of a closure (1).

8. The method as claimed in claim 7 which comprises urging a portion of a corner (2') of the tube (2) into a respective recess (6) of the closure (1).

9. The method as claimed in claim 8 which comprises deforming a portion (2') of the tube (2) into a respective recess (6).

10. The method as claimed in claim 8 or claim 9 which comprises urging at least two portions (2') of the tube (2) into respective recesses (6).

11. The method as claimed in any of claims 7 to 10 which comprises at least partially severing the tube (2) at a position which is adjacent a portion (2') of tube which is urged into a recess (6).

12. Apparatus for securing a closure (1) to an end of a tube (2) comprising die means (18) which, in use, is adapted to urge a portion (2') of the tube into a recess (6) provided in a sidewall (3) of the closure.

13. Apparatus as claimed in claim 12 in which the die means (18) comprises cutter means (20, 21), and the cutter means, in use, is operative to cut or at least partially sever the tube (2) at a position which is adjacent to that portion (2') of the tube which is urged into the recess (6).

14. Apparatus as claimed in either claim 12 or claim 13 in which the die means (18) comprises an actuated die head.

15. Apparatus as claimed in any of the claims 12, 13 or 14 in which the die means (18) is adapted, in use, to crimp a portion (2') of the tube (2) into the recess (6).

16. Packaging which comprises a tube (2), at least one end of which is attached to a closure (1) as claimed in any of claims 1 to 6.

Drawing