CONTAINER WITH TAMPER EVIDENT CLOSURE

Abstract: A container having a hollow body portion (2) closed by a cap portion (6) has a tamper evident closure thereon which comprises at least one plug (12) carried by one of the body portion (2) and the cap portion (6) and which, with the cap portion (6) in a closed position on the body portion (2), is located in, to be a tight friction fit in, a corresponding recess (10) formed in the other of the body portion (2) and the cap portion (6), a region of weakness (18) being provided between the plug (12) and the component on which it is mounted, the arrangement being such that, on movement of the cap portion (6) from its closed position on the body portion (2), said region of weakness (18) is broken whereby, on return of the cap portion (6) to its closed position, evidence of tampering is immediately visually apparent.

Description: CONTAINER WITH TAMPER EVIDENT CLOSURE TECHNICAL FIELD The present invention relates to containers with tamper evident closures, and more particularly to such closures reacting between the cap and the body of a container to indicate unauthorised opening of the container. BACKGROUND ART In order to provide an indication of unauthorised opening of a container, for example between packaging a full container and a point of sale of the contents of the container, it is established practice to incorporate on the container a so called tamper evident closure reacting between the cap and the body of the container. Such closures are many and varied, and may comprise, for example a shrink sleeve, a circumferential tear strip or the like. In all cases, a component of the closure has to be torn or removed to enable removal of the cap from the container and access to the content of the container. Thus, authorised personnel, on receipt of a container, can determine whether or not unauthorised entry to the container has been effected, and, in the event that all is in order, can remove the closure themselves to enable authorised use . Established closures tend to suffer from various disadvantages - for example the positions of shrink sleeves may be such that they are too high or too low on the neck of the bottle to provide an effective indication of tampering having been effected, while tear strips can be expensive to produce. Often it is necessary to modify the shape of the containers to accept the closures, while the closures can sometimes be defeated by distortion of the container, for example by squeezing the neck of the container. The invention is particularly concerned with the provision of a tamper evident closure for wide necked containers of relatively malleable PVC, such as sweet jars, although it also has application to such containers of a more rigid material such as PET. The necks of PVC jars are easily squeezed or deformed whereby many existing closures are ineffective, while tear strips and the like would be expensive to incorporate in view of the substantial circumferences of wide necked containers. SUMMARY OF THE INVENTION It would be desirable to be able to provide an improved tamper evident closure particularly suited to wide necked containers of a malleable material which is economic to manufacture and which is capable of withstanding distortion/squeezing of the neck of the container. According to the present invention there is provided a container having a tamper evident closure thereon, the container having a hollow body portion closed by a cap portion and the closure being characterised by at least one plug carried by one of the body portion and the cap portion and which, with the cap portion in a closed position on the body portion, is located in, to be a tight friction fit in, a corresponding recess formed in the other of the body portion and the cap portion, a region of weakness being provided between the plug and the component on which it is mounted, the arrangement being such that, on movement of the cap portion from its closed position on the body portion, said region of weakness is broken. It will be appreciated that any disconnection of the plug from the component on which it is mounted, preferably the cap portion, is indicative that the container has been opened. In a preferred embodiment of the invention, the container has an internally threaded cap portion screwed onto an externally threaded neck on the body portion, the or each plug being integrally moulded with, to depend from the lower edge of, the cap portion to be received within a corresponding recess formed in the neck of the body portion, the or each plug and the corresponding recess being aligned when the cap portion is in its closed position on the body portion. Conveniently there are two diametrically opposed plugs formed on the cap portion and two diametrically opposed recesses formed in the neck of the body portion of the container . Preferably the or each plug is mounted to the cap portion by means of a strap one end of which is secured to the bottom edge of the cap portion by a region of weakness and on the other end of which is mounted the plug. Said strap may comprise a pair of parallel strap portions one end of each of which is secured to the bottom edge of the cap portion by an associated region of weakness, the plug being mounted on the other ends of said strap portions . The design of the strap may be such that, with the cap portion in its closed position and with the plug located in its corresponding recess in the body portion, the strap is capable of being gripped to facilitate removal by twisting by authorised users. The or each plug may be mounted to its corresponding strap by a further region of weakness whereby, on authorised opening of the container, a strap can be totally removed from the container by appropriate breakage of the regions of weakness between the cap portion and the strap and between the plug and the strap. The strap may be provided with gripper means thereon to facilitate said total removal of the strap from the container . In an alternative embodiment of the invention, the or each plug is mounted to the cap portion by means of a strap one end of which carries said plug for location in the corresponding recess in the body portion, the other end of said strap carrying a further plug for location in, to be a tight friction fit in, a corresponding recess in the cap portion, a region of weakness being provided between the further plug and the other end of said strap. Preferably a further region of weakness is provided between the first mentioned plug and the one end of the strap . In a further embodiment of the invention the strap is secured to, to extend diametrically across the top of, the cap portion and downwardly from each end of the diameter, each end of the strap carrying a plug for location one in each of two diametrically opposed recesses in the body portion, regions of weakness being provided between each plug and its associated end of the strap. BRIEF DESCRIPTION OF THE DRAWINGS Figs 1A, IB and 1C show part of a container according to the invention incorporating a first closure with the plug prior to location in the recess, subsequent to location in the recess, and after unscrewing and replacement of the cap respectively; Figs 2A, 2B and 2C are plan views of the caps of the containers of Figs 1A, IB and 1C respectively; Figs 3A, 3B and 3C are side views of the closures of Figs. 1A, IB and 1C respectively; Figs 4 and 5 show further closures on containers according to the invention prior to insertion of the plugs into their recesses; Figs 6 and 7 are a side view and a plan view respectively of a modification of the closure of Fig. 5, and Figs 8A and 8B are side view and rear view respectively of a separate closure for a container according to the invention. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Referring to Figs 1 to 3 , there is shown part of a container comprising a body portion 2 with an externally threaded neck 4 closed by an internally-threaded cap 6, the fully closed position of the cap 6 being determined by abutment of the lower edge of the cap 6 with a circumferential shoulder 8 on the body portion 2. Alternatively, the fully closed position of the cap 6, which needs to be accurately defined, may be determined by co-operating abutments on the neck 4 of the body portion 2 and internally of the cap. Formed in the neck 4 of the body portion 2, below the thread thereon, are a pair of diametrically-opposed recesses one of which is shown at 10. Integrally moulded with the cap 6, to depend from the lower edge thereof, are a pair of diametrically opposed plugs 12. More particularly each plug 12 is attached to the cap by a strap indicated generally at 14 which includes a pair of parallel strap portions 16 extending from the plug 12 and, for each strap portion 16, a reduced thickness gate 18, the gates 18 together defining a region of weakness between the plug 12 and the cap 6. The plugs 12 are configured to be a tight, friction fit in the associated recesses 10, and are located on the cap 6 such that, with the cap 6 in its fully closed position, the plugs 12 are exactly circumferentially aligned with the associated recesses 10. Subsequent to filling the container and prior to despatch of the filled container, the tamper evident closure is effected by tightening the cap 6 onto the neck 4 of the body portion 2 and then forcibly locating the plugs 12 in their associated recesses 10. When in their recesses 10, the outer surfaces of the plugs 12 are substantially flush with the surface of the container as can be seen from Figs IB and IC, their friction fitting in the recesses 10 being such that they cannot be removed therefrom. Any attempt to unscrew the cap 6 from the body portion 2 will result in tearing of the gates 18 from the lower edge of the cap 6 as clearly indicated in Fig. IC, the arrangement being such that, on return of the cap 6 to its fully closed position, the gates 14 are displaced outwardly and angularly from their original positions, as shown in Figs IC and 3C, to indicate that tampering has taken place. The lengths of the strap portions 16 of the embodiment of Figs 1 to 3 may be slightly greater than as shown in those Figures, whereby said strap portions 16, with the cap 6 in its fully closed position and prior to breakage of the gates 18, project outwardly from the container to provide a loop which can be readily gripped to facilitate authorised breakage of the tamper evident closure. This facility can be further improved by increasing the length of the strap portions 16 as shown in Fig 4 to provide a larger loop for authorised gripping and an even more obvious indication of tampering. Fig 5 shows the embodiment of Fig 4 but in which a further line of weakness in the form of gates 18 1 is provided between the plug 12 and the adjacent end of the strap portions 16. The gates 18 1 are stronger than the gates 18 whereby the latter gates 18 tear on initial turning of the cap 6 to provide evidence of tampering. It will be appreciated that, on authorised use of the container, and subsequent to opening of the cap 6 and tearing of the gates 18, the strap portions 16 can be completely removed from the container by tearing the region of weakness provided by the gates 18 1 . Figs 6 and 7 show a modification of the embodiment of Fig 5, in that the strap 14 comprises a single extent and a tab 20 is integrally formed with the strap 14 to facilitate removal of the strap 14 from the plug 12 and the cap 6, the provision of the tab 18 enabling twisting of the strap 16 relative to the plug 12 and the cap 6 to break the lines of weakness provided by the gates 18,1s 1 . In the above described embodiments, the plugs 12 are integrally moulded with the cap 6, and the recesses 10 are formed in the body portion 2 of the container. Clearly the plugs could be on the body portion 2 and the recesses in the cap 6, while the number of plugs and recesses can be chosen to suit particular requirements, be it one, two or more. As indicated in Fig. 7, the strap 14 may comprise a single extent instead of a pair of parallel strap portions 16. Fig 8 shows a still further variation of the invention in which the plug 12 is formed on one end of an independent strap 22, gates 18 being provided between the plug 12 and one end of the strap 22 to constitute a region of weakness. The other end of the strap 22, instead of being integrally formed with, to depend from the lower edge of, the cap 6, carries thereon a further plug 24 connected to the strap 22 by a further region of weakness defined by gates 26. In this embodiment, a recess corresponding to the plug 24 is formed in the sidewall or in the top of the cap 6, the arrangement being such that, with the cap 6 in its fully closed position, the recesses in the cap 6 and the body portion 2 are vertically aligned, and the corresponding plugs 12, 24, which are both tight friction fits in their associated recesses, are pushed either manually or mechanically into the recesses to effect the tamper evident closure . In an unillustrated embodiment of the invention, there is provided a strap which is secured to, to extend diametrically across the top of, the cap, the strap including end portions which extend downwardly from the ends of the diametrical extent thereof, each end portion carrying a plug attached thereto by a region of weakness. With the cap in its fully closed position, the plugs on the strap are aligned with recesses in the body portion in which they are a tight friction fit whereby, on rotation of the cap, the regions of weakness are sheared to provide an indication of tampering. The described arrangements are particularly suited to wide necked jars of, for example, malleable PVC, in that the closures cannot be defeated by distortion and/or squeezing of the neck of the container, and are relatively economic to produce without the necessity for significant adaptation of existing jars. The invention also has application to wide necked jars of a more rigid material such as PET, as well as smaller containers for, for example, pills, capsules and the like. Containers are often lifted by their caps, and the provision of the plug/strap arrangement of the invention is such as to strengthen considerably the connection between the cap and the body portion. Although described in relation to screw-on caps, the invention is applicable to containers with push-on caps. The regions of weakness may be formed by other than gates, for example by mechanically thinning the material to form lines of weakness. Other modifications and variations will be apparent to those skilled in the art.

Claims: CLAIMS 1. A container having a tamper evident closure thereon, the container having a hollow body portion (2) closed by a cap portion (6) and the closure being characterised by at least one plug (12) carried by one of the body portion (2) and the cap portion (6) and which, with the cap portion (6) in a closed position on the body portion (2), is located in, to be a tight friction fit in, a corresponding recess (10) formed in the other of the body portion (2) and the cap portion (6) , a region of weakness (18) being provided between the plug (12) and the component on which it is mounted, the arrangement being such that, on movement of the cap portion (6) from its closed position on the body portion (2) , said region of weakness (18) is broken. 2. A container as claimed in claim 1 and having an internally threaded cap portion (6) screwed onto an externally threaded neck (4) on the body portion (2) , the or each plug (12) being integrally moulded with, to depend from the lower edge of, the cap portion (6) to be received within a corresponding recess (10) formed in the neck (4) of the body portion (2) , the or each plug (12) and the corresponding recess (10) being aligned when the cap portion (6) is in its closed position on the body portion (2) . 3. A container as claimed in claim 2 in which there are two diametrically opposed plugs (12) formed on the cap portion (6) and two diametrically opposed recesses (10) formed in the neck (4) of the body portion (2) of the container . 4. A container as claimed in claim 2 or claim 3 in which the or each plug (12) is mounted to the cap portion (6) by means of a strap (14) one end of which is secured to the bottom edge of the cap portion (6) by a region of weakness (18) and on the other end of which is mounted the plug (12) . 5. A container as claimed in claim 4 in which the strap (14) comprises a pair of parallel strap portions (16) one end of each of which is secured to the bottom edge of the cap portion (6) by an associated region of weakness (18), the plug (12) being mounted on the other ends of said strap portions (16) . 6. A container as claimed in claim 4 or claim 5 in which the strap (14) is such that, with the cap portion (6) in its closed position and with the plug (12) located in its corresponding recess in the body portion (2), the strap (14) is capable of being gripped to facilitate removal by twisting by authorised users. 7. A container as claimed in any one of claims 4 to 6 in which the or each plug (12) is mounted to its corresponding strap (14) by a further region of weakness (18 1 ) whereby, on authorised opening of the container, a strap (14) can be totally removed from the container by appropriate breakage of the regions of weakness (18, 18 1 ) between the cap portion (6) and the strap (14) and between the plug (12) and the strap (14) . 8. A container as claimed in claim 7 in which the strap (14) is provided with gripper means (20) thereon to facilitate said total removal of the strap (14) from the container. 9. A container as claimed in claim 1 in which the or each plug (12) is mounted to the cap portion (6) by means of a strap (22) one end of which carries said plug (12) for location in the corresponding recess (10) in the body portion (6), the other end of said strap (22) carrying a further plug (24) for location in, to be a tight friction fit in, a corresponding recess in the cap portion (6), a region of weakness (26) being provided between the further plug (24) and the other end of said strap (22) . 10. A container as claimed in claim 9 in which a further region of weakness (18) is provided between the first mentioned plug (12) and the one end of the strap (22) . 11. A container as claimed in claim 1 in which the strap is secured to, to extend diametrically across the top of, the cap portion and downwardly from each end of the diameter, each end of the strap carrying a plug for location one in each of two diametrically opposed recesses in the body portion, regions of weakness being provided between each plug and its associated end of the strap.

Inventors: THOMPSON DAVID NOBLE, THOMPSON, DAVID, NOBLE
Applicants: AUDUS NOBLE LTD, THOMPSON DAVID NOBLE, AUDUS NOBLE LIMITED, THOMPSON, DAVID, NOBLE
Application year: 1998
Main classification: B65D55
IPC codes: B65D55