GB2261873A

GB2261873A - A tamper-evident closure for a container

Info

Publication number: GB2261873A
Application number: GB9125294A
Authority: GB
Inventors: Stephen Bicknell; Michael John Hydes
Original assignee: BUNZL CUSTOM MOULDING Ltd
Current assignee: BUNZL CUSTOM MOULDING Ltd
Priority date: 1991-11-28
Filing date: 1991-11-28
Publication date: 1993-06-02
Anticipated expiration: 2011-11-28
Also published as: GB2261873B; GB9125294D0

Abstract

The snap fitting closure 20, in use, closes an opening of a container, the container 10 defining a peripheral wall 17 adjacent the opening and having thereon a rib 15 projecting outwardly therefrom co-operating with a retaining bead 27 on the closure 20 and a surface (16, Figure 1) projecting outwardly therefrom co-operating with tear-off retaining means 28 on the closure. The second retaining means 28 is a skirt which has an outer surface 32 which tapers inwardly and terminates at a free end 34 substantially in engagement with the peripheral wall (17) to inhibit insertion of a tool or fingernail between the peripheral wall and the skirt 28. A weakened section 29 is provided between the skirt 28 and the bead 27 and a tear tab (35, Figure 1) is preferably provided on the skirt 28. Sealing ribs 25 may be provided on the closure. <IMAGE>

Description

A TAMPER-EVIDENT CLOSURE FOR A CONTAINER The Invention relates to a tamper-evident closure for a container and is particularly concerned with a closure having a tear-off section to enable the closure to be removed from the container Tamper-evident container closures having tear-off sections have been known for many years and an example of such can be seen in GB-A-1377616.

In GB-A-1377616, a single external retaining surface projects outwardly from a peripheral wall of the container adjacent an opening n the container. The retaining surface Locates 1n a ---..Ing groove in the closure. A tear-off strip is arranged immediately beneath the groove and ce the strip is tern off the closure can be removed from the container. However the groove is the only means for retaining the closure on the container.

An object of the present invention is to provide a ciosure which is more secure than that shown in the above specification and which will also resist the insertion of a tool or fingernail between the lower end of the closure and the wall of the container.

According to a first aspect of the invention there is provided a tamper-evident closure closing an opening of a container, the container defining a peripheral wail adjacent the opening and having thereon a first surface projecting outwardly therefrom co-operating with first retaining means on the closure and a second surface projecting outwardly therefrom cooperating with tear-off second retaining means on the closure, the second retaining means having an outer surface which tapers inwardly and terminates at a free end substantially in engagement with an axially extending section of the peripheral wall of the container to inhibit insertion of a tool or fingernail between said section of the peripheral wall and the second retaining means.

With such an arrangement, the first and secona retaining means make it extremely difficult to remove the closure from the container without first removing the tear-off second retaining means and the configuration of the second retaining means makes it extremely difficult to introduce a tool or fingernail for the purposes of prising off the closure.

Preferably, the second retaining means forms a peripheral skirt. The skirt preferably terminates at a cylindrical axially-extending section of the container. Preferably the second retaining means is a ciose fit against the said axially extending section of the peripheral wall of the container so that there is virtually no gap whatsoever between the lower edge of the second retaining means and the adjacent peripheral wall of the container. That is unlike the closure described in GB-A-l377616 where a skirt beneath the tear-off band has a lower edge which terminates at an inwardly curved outer section of the container which does not lend itself to the lower edge of the skirt fitting closely against the container wall.

The second surface m be inclined. For example, it man take the form of a substantially frusto conical surface The second retaining means may include an inclined surface portion which, again, may be frusto-conical.

Preferably, the inclination of the inner surface part on 15 similar to the Sf that of the second surface.

The second retaining means may include a further inner surface portion which lies substantially parallel with an adjacent wall of the container and is preferably in firm engagement therewith.

Preferably, the further inner surface and the tapering outer surface portion of the closure terminate to form said free end of the closure which iies closely adjacent the wall of the container.

A weakening section for the tear-off second retaining means is preferably defined by an intersection of part of the first retaining means and part of the second retaining means, for example, the aforesaid inclined surface of the second retaining means.

Preferably, the said first surface of the container projects outwardly to a position further from the axis of the container than the second surface.

Preferably, the first and second surfaces are formed as part of a common outwardly directed protrusion on the container. The protrusion preferably includes a cylindricai section extending axially between the said first and second surfaces, the first retaining means of the closure projecting inwardly beneath the first surface towards the said cylindrical section.

The said first surface is preferably a radial surface and preferably extends around the periphery of the container Seaiing means such as axially spaced peripheral ribs may be disposed between the closure and container preferably between the said first surface and the open end of the container. The sealing means is preferably arranged on the closure.

According te a second aspect of the invention there is provided a tamper-evident closure for closing an opening of a container, the closure having the features of the tamper-evident closure referred to in said first aspect of the invention or in any of the consistory clauses related thereto concerned with the closure.

According to a third aspect of tne invention there provided a container for receiving a tamper-evident ciosure, tne container having the features of the container referred to in said first aspect of the invention or in any of the consistory clauses related thereto concerned with the container.

A tamper-evident closure and a container on which the closure locates will now be described by way of example with reference to the accompanying drawings in which: Fig. 1 is a perspective view of part of the closure and the container shown partly broken away, Fig.2 is a cross section of part of the closure and container shown in Fig. 1 and Fig. 3 is an elevation of the container drawn to a smaller scale and shown partly broken away.

A cylindrical container 10 has an outward protrusion 12 adjacent its open upper end as viewed in the drawings. The protrusion 12 comprises a first rib 13 having a frusto conical upper surface 14 and a radial lower surface 15. The rib 13 extends fully around the periphery of the container 10. The protrusion 12 is also formed with a frusto conical lower surface 16. The frusto conical surfaces 14, 16 extend from a wall 17 of the container 10. The protrusion 12 also includes a cylindrical surface 18 between the radial surface 15 and the frusto conical surface 16. The surfaces 15, 16 constitute the aforesaid first and second surfaces respectively of the container.

The container 10 has a cylindrical closure 20 having a circular top 22 and a side wall 23. The side wall 23 has an internal surface 24 formed with upper and lower peripheral sealing ribs 25, a frusto-conical section 26 of complementary shape to the frusto conical surface 14, a primary retaining bead 27 which extends beneath the radial surface 15 and a frustoconical secondary retaining surface 28 which extends beneath the frusto conical surface 16. The primary retaining bead 27 extends towards the cylindrical surface 18. The primary retaini-ng bead 27 and the secondary retaining surface 28 constitute the aforesaid first and second retaining means respectively. A weakening line 29 is formed at the intersection of the frusto-conical surface 28 and the lower terminal end of the primary retaining bead 27.

The secondary retaining surface 28 is formed on a tear-off skirt 30 having a tapering external surface 32 which terminates at its free lower end at an edge 33 defined by an intersection between the tapering surface 32 and a cylindrical inner surface 34. As shown clearly in Fig.2, the end 33 and surface 34 engage the outer surface of the container wall 17.

The interengagement of the side wai 17 with the end 3 and surface 34 makes it virtually impossible for an individual to insert a fingernail underneath the skirt 30 or a tool such as a knife in an attempt to prise the closure 20 from the container 10.

The skirt 30 is connected to a fin tab 35 which itseif is frangible connected to a flange 36 on the closure 20.

To remove the closure 20, the tab 35 is broken away from the flange 36 and the tab 35 is used to tear away the skirt 30 around the weakening line 29 so that the skirt 30 becomes detached from the side wall 23 of the ciosure. Once the skirt 30 has been detached, the closure can be removes from the container 10 by manuaily flexing the primary retaining bead 27 over the rib 13. In order to replace the closure, it is relocated over the upper end of the container 10 and pressed downwardly until the primary retaining bead 27 snaps over the rib 13.

The double retaining effect given by the primary retaining bead 27 and the secondary retaining surface 28 is an advantageous feature. Also, the use of the tear-off skirt 30 to prevent the introduction of a fingernail or tool between the skirt and the axially extending cylindrical container wail 17 is most advantageous.

Claims

1. A tamper-evident closure closing an opening of a container, the container defining a peripheral wall adjacent the opening and having thereon a first surface projecting outwardly therefrom co-operating with first retaining means on the closure and a second surface projecting outwardly therefrom co-operating with tear-off second retaining means on the closure, the second retaining means having an outer surface which tapers inwardly and terminates at a free end substantially in engagement with an axially extending section of the peripheral wall of the container to inhibit insertion of a tool or fingernail between said section of the peripheral wall and the second retaining means.

2. A tamper-evident closure closing the opening of a container according to Claim 1, in which the second retaining means forms a peripheral skirt.

A tamper-evident closure closing the opening of a container according to Claim 2; in which the skirt terminates at a cylindrical axially-extending section of the container.

4. A tamper-evident closure closing the opening of a container according to Claim 3, in which the second retaining means is a close fit against the said axially extending section of the peripheral wall of the container.

5. A tamper-evident closure closing the opening of a container according to any preceding claim, in which the second surface is inclined.

6. A tamper-evident closure closing the opening of a container according to Claim 5, in which the second surface takes the form of a substantially frusto conical surface.

7. A tamper-evident closure closing the opening of a container according to any preceding claim, in which the second retaining means includes an inclined surface portion.

8. A tamper-evident closure closing the opening of a container according to Claim 7, in which the inclined surface portion is frusto conical.

9. A tamper-evident closure closing the opening of a container according to Claim 7 or 8, in which the inclination of the inner surface in which the inclination of the inner surface portion is similar to that of the second surface.

10. A tamper-evident closure closing the opening of a container according to any preceding claim, in which the second retaining means includes a further inner surface ortion which lies substantially parallel with an adjacent wall cf the container.

11. A tamper-evident closure closing the opening of a container according to Claim 10, in which the further inner surface portion firmly engages said adjacent wall of the container.

2. A tamper-evident closure closing the opening of a container according to Claim 10 or 11, in which the further inner surface and the tapering outer surface of the closure terminate to fcr said free end of the closure which lies closely adjacent the wall of the contaner.

A A tamper-evident closure closing the opening of a container according to any preceding Claim, fn which a weakening section for the tearoff second retaining means is defined by an intersection of part cf the first retaining means and part of the second retaining means.

14. A tamper-evident closure closing the opening of a container according to Claim 13, in which the said retaining means includes an inclined surface portion and the weakening section is defined by the intersection of part of the first retaining means and said inclined surface portion.

15. A tamper-evident closure closing the opening of a container according to any preceding claim, in which said first surface of the container projects outwardly to a position further from the axis of the container than the second surface.

16. A tamper-evident closure closing the opening of a container according to any preceding claim, in which the first and second surfaces are formed as part of a common outwardly directed protrusion on the container.

17. A tamper-evident closure closing the opening of a container according to Claim 16, in which the protrusion includes a cylindrical section extending axially between the said first and second surfaces, the first retaining means of the closure projecting inwardly beneath the first surface towards the said cylindrical section.

18. A tamper-evident closure closing the opening of a container according to any preceding claim, in which the said first surface is a radial surface.

19. A tamper-evident closure closing the opening of a container according to any preceding claim ; in which the first surface extends around the periphery of the container.

20. A tamper-evident closure closng the opening of a container according to any preceding claim, in which sealing means is disposed between the closure and container.

A A tamper-evident closure closing the pening of a container according to Claim 20, in which the sealing means comprises a peripheral rib.

22. A tamper-evident closure closing the opening of a container according to Claim 20 or 2 which the sealing means Is disposed between the said first surface and the open end cf the container.

20. A tamper-evident closure closing the opening of a container according to Claim 20, 21 or 22, in which the sealing means is arranged on the closure.

24. A tamper-evident closure closing the opening of a container according to any preceding claim and where the tear-off second retaining means is removed and the closure is removed from the container, in which the first retaining means enables the closure te be relocated on the container by snap fitting the second retaining means over a rib defining the said first surface.

25. A tamper-evident closure closing an opening of a container constructed and arranged substantially as described herein wlth reference to the accompanying drawings.

26. A tamper-evident closure for closing an opening of a container, the closure having the features of the tamper-evident closure referred to in any preceding claim.

27. A tamper-evident closure constructed and arranged substantially as described herein with reference to the accompanyin drawings.

28. A container for receiving a tamper- evident closure, the container having the features of the container referred to in any preceding claim.

29. A container constructed and arranged substantially as described herein with reference to the accompanying drawings.