GB2126565A

GB2126565A - Screw-capped container

Info

Publication number: GB2126565A
Application number: GB08223152A
Authority: GB
Inventors: Frederick G W Mills
Original assignee: U G CLOSURES AND PLASTICS LIMI; UG Closures and Plastics Ltd
Current assignee: U G CLOSURES AND PLASTICS LIMI; UG Closures and Plastics Ltd
Priority date: 1982-08-11
Filing date: 1982-08-11
Publication date: 1984-03-28
Also published as: GB2126565B

Abstract

A screw-capped container comprises a lug and a protuberance on each of the cap and the container arranged so that, when the cap is in a desired position on the container, a cap lug 17 abuts a container lug 25, positively to prevent the cap from being over-tightened, and the protuberances 15, 27 abut one another, to retain the cap in the desired position, the or each protuberance or the part on which it is located being deformable so that, on application of sufficient screwing force the protuberances are able to move over one another, thereby to allow the cap to be unscrewed from or screwed-on to the desired position. <IMAGE>

Description

SPECIFICATION Screw-capped container The present invention relates to a screw-capped containerwhich has an arrangement for retaining the cap in a desired position relative to the container.

Screw-capped containers, especially bottles, are commonly used to contain a wide variety of liquids, such as shampoos, disinfectants and perfumes.

Repeated screwing-on or unscrewing ofthe cap, especially if the cap is overtightened, may cause the screw th read on either the cap or the container to become deformed. This may weaken the seal formed by the cap on the container, thus allowing loss ofthe contents ofthe container by evaporation andlor leakage. Moreover, the cap may work loose, for instance during transit, or become unscrewed accidentally, again allowing loss ofthe contents of the container.

Overtightening ofthe cap on the container may also result in the cap being excessively stressed and this may, especially in a hostile environment or in the presence of a hostile product, result in cracking and consequent leakage. Overtightening may also result in thread jumping which may cause leakage and thread damage to occur.

Some screw-caps for containers, which may be non-circular in cross-section, are designed to be aligned in a particular position on the container so that the closed container has a visually pleasing aspect, as well as to avoid overtightening. The cap may be designed to be aligned with features of pattern or shape on the bottle. However, if either ofthe threads becomes deformed, it is difficultto align the cap on the container in the desired position.

It is therefore desirable to provide a screw-capped container having an arrangement for retaining the cap on the container in a desired position.

Ascrew-capped bottle having such an arrangement is disclosed in British Patent Specification No. GB-A-1 261 772. The cap disclosed therein has a hem on its skirt which snaps into matching engagement with a shoulder on the bottle to preventovertightening.

However, the reliability of this arrangement depends to some extent on the quality ofthe material from which the bottle andlor cap are made. If the material is too eiastic, the arrangement may be deformed so that it is no longer possible to ensure that the cap and bottle retain the desired relative position.

Anotherscrew-capped bottle having such an arrangement is disclosed in British Patent Application No. GB-A-2 017 The arrangement comprises a notch bearing member on the cap or bottle which co-operates in snap lock fashion with a protuberance on the bottle or cap respectively. The notch bearing member orthe protuberance is deformableto enable the protuberance to snap into the notch.

The efficiency of this arrangement is also to some extent dependent on the quaiity of the material used to form the protuberance or notch bearing member.

For instance, if one is made of a softer material than the other, the opening and closing ofthe bottle may result in the wearing away of the softer member, especially as the cap snaps into place on the bottle.

Thiswill mean that itwill no longer be possibleto ensurethatthe cap is retained in the desired position.

In many cases, the cap will be of a softer material than the bottle, and it will therefore be the cap which wears away.

According to the present invention, there is provided a screw-capped container, the cap and the container each having a lug and a protuberance arranged so that, when the cap is in a desired position on the container, the lugs abut one another, positively to prevent the cap from being over-tightened, and the protuberances abut one another, to retain the cap in the desired position, the or each protuberance or the part on which it is located being deformable so that, on application of sufficient screwing force the protuberances are able to move over one another, thereby to allowthe cap to be unscrewed from or screwed-on to the desired position.

It is envisaged that the present invention will be of particular, but not exclusive, use where the container is a bottle, especially on having a cap of non-circular cross section.

Preferably both the cap and the container have two lugs, disposed diametrically opposite one another, and two protuberance also disposed diametrically opposite one another. The lines connecting the lugs and protuberances may be coincident or may be offset from each other by an angle of up to 45". Preferably, the lines are only slightly offset.

In a preferred embodiment, the protuberances on the cap are located on a part of the cap which is resiliently deformable. Conveniently, the protu berances are also to some extent resiliently deformable.

Conveniently the or each protuberance on eitherthe container or the cap has on one side a ramp up which the protuberance with which it co-operates moves towardsthedesired position, the otherside ofthe protuberance being disposed radiallysothatthe co-operating protuberance snaps into place as the desired position is reached. In a preferred embodiment, the or each ramped protuberance is formed on the container and is not resiliently deformable. The protuberance which co-operates with a ramped protuberance is conveniently part-spherical.

The cap may comprise a socket part, defining a screw thread for co-operation with the screw thread on the container, and a skirt part surrounding the socket part. The socket part is preferablytubular, but may also be ofellipsoidal or other rounded crosssectional shape.

In a preferred embodiment, the skirt part is made of a resiliently deformable material and has the or each protuberancethereon so thatthe skirt is able to deform to allow the protuberances to move over one another. This embodiment is particularly suitable for use with screw-capped bottles wherein the caps are non-circular in cross-section.

Preferably, the skirt is oval in cross-section. However, it may also be of any other asymmetric rounded shape or any angular shape in cross-section. For instance, the skirt may be square or rectangular in cross-section.

The cap may also include a seal member disposed inside itsscrewthreadforfitting in sealing relationship insidethe opening ofthe container when the cap is in the desired position.

Each lug on the cap may comprise a fiat piece of material extending beyond the screw thread, the co-operating lug on the container being formed below the screwthread thereon. Preferably the or each lug on the container is strengthened, for instance by a wedge portion behind it.

In a preferred embodiment, wherein the container is a bottle having a neck on the top of which is formed the screw th read, each co-operating lug on the bottle is formed on the neck immediately below the screw thread. However, the lugs on the bottle may also be located on the shoulder or body ofthe bottle with the lugs on the cap located on the outside ofthe cap or its skirt.

The container may be manufactured from any of the materials presently used, for instance glass, plastics or a composite material, in conventional fashion. For instance, plastic containers may be manufactured by injection moulding, vacuum forming or blow moulding.

Preferably the caps are made of plastic materials using, for example, an injection moulding technique.

Although the container is preferably a bottle, it may also be a pot, jar or tin, depending on the material which it is designed to contain.

The advantage ofthe screw-capped container of the present invention is that the cap is firmly retained in the desired position and cannot be overtightened on the container. There is a much reduced chance of the screwthreads becoming deformed, ofthe cap crack ing or splitting due to stress, orofthread jumping occurring. Moreover, the cap cannot become unscrewed accidentally. Good sealing ofthe container can be readily achieved and loss ofthe contents ofthe capped container by evaporation or spillage is sub stantially avoided. The positive positioning of the cap on the container ensures that caps of special design or non-circular cross-section can be correctly aligned on theircontainers. The snap lock achieved on screwingon the cap to the desired position indicates to a user thatthe cap is fully screwed on.

A preferred embodiment of a screw-capped container according to the present invention wherein the container is a bottle is described, byway of example only, with reference to the accompanying drawings, in which: Figure lisa planviewfrom belowofthecap; Figure 2 is a sectional view along line 2-2 of Figure 1; Figure 3 is a sectional view along line 3-3 of Figure 1; Figure 4 is a plan view ofthe bottle; Figure 5 is a front view of the neck of the bottle; and Figure 6 is a side view ofthe neck ofthe bottle.

Referring to Figures 1 to 3, the cap 1 comprises a plastics moulding having a base 3 on which are concentrically formed a cylindrical seal member 5, a tubularsocket part 7 and a skirt part 9.

A screw th read 11 is formed on the inside ofthe socket part 7. Strengthening ribs 13 are formed between the skirt part 9 and the socket part 7 and also serve to locate the cap as it is applied to the bottle.

The skirt part 9 is oval in cross-section, has a pair of part-spherical protuberances 15formed on the lower part of its inside on opposite ends of its minor axis, and is resiliently deformable.

A pair of lugs 17 in the form of non-deformable stop flats are formed between the socket part7 and skirt part 9, and extend from the base 3 past the screw 11.

The lugs 17 are also disposed at or near opposite ends of the minor axis of the skirt part 9.

Referring now also to Figures 4to 6, the bottle 18 comprises a plastics moulding having a body (not shown), an oval shoulder portion 19 and a neck portion 21. A screw thread 23, for co-operation with the screw th read 11 on the cap, is formed on the top of the neck portion 21.

Immediately belowthe screw th read 23 are formed, 6n diametrically opposite sides ofthe neck portion 21, two lugs 25 for co-operation with the lugs 17 on the bottle. The lugs 25 are strengthened bythe formation of wedge shapes 26 behind them so that the lugs are not deformable.

On the lower part ofthe neck portion 21, on diametrically opposite sides thereof, are formed two ramp-shaped protuberances 27 for co-operation with the protuberances 15 on the cap. As can be seen from Figures 4 and 5 the lugs 25 are slightly offset from the protuberances 27. The protuberances 27 increase in width towards the lugs 25.

The dimensions a, band c shown in Figure 3 are equal to the dimensions d, e and f respectively shown in Figure 4.

In use, the cap 1 is screwed onto the bottle 18 and the lugs 17 move towards the lugs 25. As the lugs approach oneanother,the protuberances 15 approach the ramp-shaped protuberances 27. As the protuberances 15 move overthe ramps, the skirt part 9 resilientlydeformstoallowthis movement.

The cap and bottle are so designed that, as the lugs 17 and 25 come into abutment, the protuberances 15 reach the wider end of the protuberances 27 and the resilience of the skirt part 9 causes the protuberances to snap back radially towards the neck portion 21. The radial faces of the protuberances 27 then abutthe protuberances 15, thus locking the cap on the bottle.

When the cap is in this position the seal member 5 comes into sealing relationship with the inside ofthe screw-threaded part of the neck portion 21, and the major axis ofthe skirt part 9 is parallel with the major axis ofthe shoulder portion 19. This is the desired position for this screw-capped container.

To unscrewthe cap 1, sufficient unscrewing force is applied to cause the skirt part 9to deform so that the protuberances 15 and 27 are able to move over one another. As the protuberances 15 and 27 move over one another, the skirt part 9 recovers its original form and the cap 1 can easily be unscrewed.

The arrangement described above is an improvementoverthe previously disclosed arrangements becausethe lugswhich preventovertightening may be made using non-deformable material and construction, thereby ensuring that the cap is only screwed on as far as the desired position, while the co-operating protuberances ensure that the cap is snap-locked in the desired position and cannot become accidently unscrewed.

CLAIMS (Filed on 1 August 1983) 1. Ascrew-capped container, the cap and the container each having a lug and a protuberance arranged so that, when the cap is in a desired position on the container, the lugs abut one another, positively to preventthe cap from being over-tightened, and the protuberances abut one another, to retain the cap in the desired position, the or each protuberance or the part on which it is located being deformable so that, on application of sufficient screwing force the protu berances are able to move over one another, thereby to allowthe cap to be unscrewed from or screwed-on to the desired position.

2. A screw-capped container according to claim 1 wherein the container is a bottle and the cap has a non-circular cross-section.

3. A screw-capped container according to claim 1 or claim 2 wherein both the cap and the container have two lugs, disposed diametrically opposite one another, and two protuberances, also disposed diametrically opposite one another 4. A screw-capped container according to claim 3, wherein the lines connecting the lugs and protuberances are coincident or are offsetfrom each other by an angle of up to 45 .

5. A screw-capped container according to any one of claims 1 to 4, wherein the protuberances on the cap are located on a part of the cap which is resiliently deformable.

6. A screw-capped container according to any one of claims 1 to 5, wherein the or each protuberance on eitherthe container orthe cap has on one side a ramp up which the protuberance with which it co-operates moves towards the desired position, the other side of the protuberance being disposed radially so that the co-operating protuberancesnapsinto place as the desired position is reached.

7. Ascrew-capped containeraccording to claim 6, wherein the or each romped protuberance is formed on the container and is not resiliently deformable.

8. A screw-capped container according to any one of claims 1 to 7, wherein the cap comprises a socket part, defining a screw thread for co-operation with the screw th read on the container, and a skirt part surrounding the socket part.

9. A screw-capped container according to claim 8, wherein the skirt part is made of a resiliently deformable material and has the or each protuberance thereon so that the skirt is able to deform to allow the prntubernncesto move over one another.

10. A screw-capped container according to any one of claims 1 to 9, wherein the cap includes a seal member disposed inside its screw thread for fitting in sealing relationship inside the opening of the containerwhen the cap is in the desired position.

11. Ascrew-capped container according to any one of claims 1 to 10, wherein each lug comprises a flat piece of material extending beyond the screw thread, the co-operating lug on the container being formed belowthe screwth read thereon.

12. A screw-capped container according to any one of claims 1 to 1 1,wherein the oreach lug on the container is strengthened, for instance by a wedge portion behind it.

13. Ascrew-capped container according to claim 2 or any claim dependent thereon, wherein each cooperating lug on the bottle is formed on the neck immediately below the screw th read.

14. Ascrew-capped container according to any one of claims 1 to 13,wherein the caps are made of plastic materials using, for example, an injection moulding technique.

15. A screw-capped container according to claim 1, substantially as hereinbefore described with reference to the accompanying drawings.

16. A screw-cap for location on a containerto provide a screw-capped container according to any oneofclaims 1 to 15.

17. A containerfor receiving a cap to provide a screw-capped container according to any one of

Claims

claims 1 to 15.