WO1985001271A1

WO1985001271A1 - Closures for containers

Info

Publication number: WO1985001271A1
Application number: PCT/GB1984/000313
Authority: WO
Inventors: Michael Witt; Peter John Whitehead
Original assignee: United Glass Limited
Priority date: 1983-09-15
Filing date: 1984-09-13
Publication date: 1985-03-28
Also published as: GB2155449B; IT8422674A0; ES289582U; ES289582Y; IT1175741B; GB8511596D0; AU3431284A; IE842152L; EP0156850A1; GB2155449A; PT79174A; IE56845B1; PT79174B; GB8324789D0

Abstract

A pilferproof closure comprises a cap (1) adapted for screw-threaded connection with the container or with, for example, a non-refillable fitment (11) affixed thereto, a frangible ring (30) axially movable with the cap on the container or fitment, and means formed on the ring and on the container or fitment which come into engagement during removal of the cap from the container or fitment and permit complete removal of the cap only after fracture of the frangible ring. The frangible ring may consist of an upper annular ring (31) integrally attached to a lower annular ring (32) through bridges (33), the upward extensions of which form buttresses (34) which extend radially outwardly of the upper annulus (31). The cap (1) cannot be removed unless the ring (30) is first fractured.

Description

CLOSURES I ΠR CONTAINERS

This invention relates to container closures, and especially to closures of the so called "pilferproof" type.

"Pilferproof" closures are well known and widely used, and their object is to provide visual evidence that containers to which they have been applied have or have not been tampered with, for one reason or another. "Pilferproof" closures are made from both metal and plastics materials, the metal types being more widely used. One known type comprises an overcapsule or sleeve, e.g. of lead/tin or shrunk plastics. Another well known type consists of a cap shell, unthreaded in the case of metal or pre-threaded in the case of plastics, to the bottom of which is attached by spaced frangible bridges a security or pilferproof ring. When the closure is applied to a container the security ring is deformed or shrunk below a retaining bead on the container, to prevent axial movement of the closure off the container. When the closure is rotated to remove it from the container, the bridges fracture, thus indicating that the container has been opened .

In the spirits industry it has become standard practice to fit the spirits containers with non-refillable fitments. Such fitments comprise one-way valves which allow the dispensing of the fluid from the container but not the re-filling of the container. Thus, when a container filled with spirits is fitted with a non-refillable fitment, it becomes impossible to adulterate or dilute the contents of the container. Une particular non-refillable fitment which has achieved considerable popularity is that described in U.K. Patent Specification No : 1, 178, 237, known as the "Whittam" fitment. Such a fitment comprises, a valve body which fits within the nock of the container, an annular shoulder or flange which fits over the container neck rim, and a screw-threaded pouring spout through which the container contents are dispensed and to which is screw-threadedly attached a cap. The fitment is held on the container by means of a cowl, which is flanged over the annular shoulder and deformed into an annular recess on the container neck beneath the annular shoulder. It has become popular to cover nonrefillable fitments such as that mentioned above with pilferproof closures. These are frequently of the aforementioned capsule type. A disadvantage of these is that they must be applied in a subsequent step to the primary closure application step.

It is an object of the present invention to provide an improved pilferproof closure. It is a particular object of the invention to provide such a closure which can be used in association with a nonrefillable fitment.

According to the present invention a closure for a container comprises a cap adapted for screwthreaded connection with the container or with a member affixed thereto (e.g. a non-refillable fitment), a frangible ring axially movable with said cap on said container or member, and means formed on said ring and on said container or said member which com e into engagement during removal of said cap from said container or said member and permit complete removal of said cap only after fracture of said frangible ring. In a preferred embodiment the cap is adapted for screw-threaded connection to a non-refillable fitment affixed to the container, for example by means of a metal or plastics cowl.

The cap may have a single skirt, or, and preferably, it has inner and outer skirts, the inner skirt being screw-threaded for attachment to the container or to a member affixed thereto and the frangible, ring being held between the inner and outer skirts, for example by means of cooperating shoulders formed on the ring and on the inner wall of the outer skirt of the cap.

In a preferred embodiment the frangible ring comprises an, upper annulus and a lowεr annulus of larger radius than the upper annulus, the two annuli being attached together by means of spaced bridges. Such bridges are suitably equi-spaced, and there may for example be three or four of them.

The bridges may form buttresses extending radially outwardly from the upper annulus, and each having a bead or shoulder which engages a corresponding bead or shoulder formed on the inside of the cap skirt. The lower annulus is suitably provided with one or more inwardly-and-upwardly-directed lips which are intended to encage with a shoulder formed on the container or on the member affixed thereto when an attempt is made to remove the cap from the container. Preferably the engaging parts of the lip or lips and the shoulder are spaced a small distance apart when the cap is fully secured on the container, so that a small amount of upward movement of the cap relative to the container is permitted upon unscrewing of the cap, before the lip or lips come into engagement with the shoulder. At this point, continued removal o f the cap from the container can only be achieved if the frangible ring is broken. Breakage of the frangible ring may occur by virtue of the connection between each bridge and the adjacent portions of the lower annulus being completely severed, in which case the portion of the lower annulus will fall away. In a preferred embodiment, however, the connection between each bridge and one of the adjacent portions of the lower annulus is stronger than the connection between the bridge and the other adjacent portion, so that the ring breaks by virtue of the breakage of the weaker connections and each portion of the annulus remains attached at one end only to a bridge. In this way the broken ring provides clearly visible evidence of tampering, particularly if the length of the cap skirt is selected such that its lower end does not obscure the ring.

An embodiment of the invention will now, be described with reference to the drawings, in which Figure 1 is an exploded view of a closure according to the invention; and

Figure 2 is a part-sectional elevation of the closure of Figure 1 , fitted onto the neck of a container. Referring to the drawings, a cap 1 comprises an inner cap skirt 2, internally screw-threaded, and an outer skirt 3 provided with external knurling 4. Radially inwardly of the inner skirt 2 is an annular sealing flange 5.

Affixed within the neck 10 of a container is a non-return fitment 11 comprising a valve body 12, an annular shoulder 13 and a screw-threaded pouring spout 14, the pouring spout being screw-threaded for engagement with the inner cap skirt 2. Between the fitment 11 and the container neck 10 is an annular sealing disc 15. The fitment 11 is held on the container neck 10 by means of a cowl 16 which is flanged over the top of shoulder 13, as at 17, and is rolled into a circumferential groove 18 and beneath an annular bead 19 on the container neck 10. Between the shoulder 13 and the pouring spout 14 of the fitment 12 is formed an annular step 20 having an annular overhang 21.

Between the cap 1 and the fitment 11 is a frangible ring 30, consisting of an upper annular ring 31 integrally attached to a lower annular ring 32, of larger diameter than the ring 31. Rings 31 and 32 are joined through bridges 33, the upward extensions of which form buttresses 34 which extend radially outwardly of the upper annulus 31.

In the embodiment shown, there, are four bridges 33, and the lower annulus 32 is effectively divided into four segmental portions extending between, and joined to, adjacent bridges 33. As will be seen most clearly from the bridges 33 shown in Figure 1, the connection 330 between the bridge and the segmental portion on one side of itis stronger than the connection of the bridge and the segmental portion on its other side, which is a weak and readily-frangible connection.

Formed inwardly of each segmental portion of the ring 32 is a lip 35 which, as better seen from Figure 2, extends upwardly and inwardly from the ring 32. The top of the lip 35 is spaced a short distance from but in axial alignment with, the overhang 21 of the fitment 11, when the closure is in the fully engaged position shown in Figure 2, and presses against the side surface of the step 20. Each buttress 34 is formed with a hook 36 engaging an annular groove 6 formed on the inside wall of the outer cap skirt 3.

The closure of the invention may be attached to a container in one of two ways. In the first method, the fitment 11 is firstly affixed to the neck 10 of the container by means of the metal cowl 16. The ring 30 is inserted in the lower end of the cap 1, and the cap is screwed onto the fitment 11. As lip 35 contacts the annular overhang .21 , it is deflected outwardly so as to pass over the overhang 21 and then resumes the configuration shown in Figure 2.

Alternatively, a unit consisting of the cap 1, ring 30, fitment 11 and cowl 16 may be assembled preliminarily. This whole fitment may then be attached to the container by placing it on the container, applying pressure to the top of the cap 1, and rolling the cowl 16 into the groove 10 and beneath the bend 19 on the container neck. Top pressure is applied to the cowl through the skirt of the cap by a slight temporary distortion of the top of the cap.

Initial unscrewing movement of the cap 1 has the effect of moving the ring 30 axially upwardly with it. After a small axial movement the top of lip 35 comes into engagement with the annular overhang 21, and further axially upward movement of lip 35 is prevented. Continued upward movement of the cap 1, and thus the upper annulus 31 by virtue of the engagement of hook 6 with groove 36, sets up an axial tension in the connections between the bridges 33 and the lower annulus 32. Further continued unscrewing of the cap 1 results in the weaker connections between the bridges 33 and the ring 32 fracturing, and after this the cap 1 can be com pletely removed. The top portion of ring 30 remains in the cap, with the four portions of the lower annulus swinging about a respective bridge It is thereafter impossible to reconstitute the lower annulus, and this provides clear evidence that the cap has been removed.

All the corponents of the closure of this invention are suitably moulded from plastics material, e.g. bolyethylene, polystyrene, and can be used in association with both plastics and glass containers. The frangible ring is suitably made of a relatively soft material , e.g. high density polyethylene, to enable the lips 35 of the ring to ride over the overhang 21 during application of the closure. The cowl 16 has been described herein as a metal cowl . It could equally well be made from a plastics material , and attached to the neck 10 of the container by means, for exampl e, of the construction illustrated in Figure 2 of our International Application No : PCT/GB83/00129.

Claims

CLAIMS :

1. A closure for a container comprising a cap adapted for screw-threaded connection with the container or with a member affixed thereto, a frangible ring axially movable with said cap on said container or member, and means formed on said ring and on said container or said member which come into engagement during removal of said cap from said container or said member and permit complete removal of said cap only after fracture of said frangible ring.

2. A closure according to claim 1 wherein the cap is adapted for screw-threaded connection with a non-refillable fitment affixed to the container.

3. A closure according to claim 1 or 2 wherein the cap has inner and outer skirts, the inner skirt being screwthreaded for attachment to the container or the member affixed thereto, and the frangible ring being held between the inner and outer skirts.

4. A closure according to claim 3 wherein the frangible ring is held between the inner and outer skirts by means of cooperating shoulders formed on the ring and on the inner wall of the outer skirt.

5. A closure according to any of claims 1 to.4 wherein the frangible ring comprises an upper annulus and a lower, annulus of larger radius than the upper annulus, the two annuli being attached together by means of spaced bridges.

6. A closure according to claim 5 wherein there are three or four bridges and the bridges are equi-spaced.

7. A closure according to claim 5 or 6 wherein the bridges form buttresses extending radially outwardly from the upper annulus, each buttress having a bead or shoulder which engages a corresponding bead or shoulder formed on the inside of the cap skirt.

8. A closure according to any of claims 5 to 7 in which the lower annulus is provided with one or more inwardlyand-upwardly-directed lips for engagement with a shoulder formed on the container or on the member affixed thereto.

9. A closure according to any of claims 5 to 8 wherein the connection between each bridge and one of the adjacent portions of the lower annulus is stronger than the connection between the bridge and the other adjacent portion of the lower annulus.