WO1998012119A1

WO1998012119A1 - Reusable closure

Info

Publication number: WO1998012119A1
Application number: PCT/AU1997/000609
Authority: WO
Inventors: Brian Albert Frazer Smith
Original assignee: Protech Development Corporation Pty. Ltd.
Priority date: 1996-09-17
Filing date: 1997-09-17
Publication date: 1998-03-26
Also published as: AR009796A1; ZA979115B; TW342371B; AUPO239396A0

Abstract

A reusable closure for an opening in a container (1) defined by at least one upstanding wall having an inner and an outer surface, the closure including: a top (8) to cover the opening; at least one pair of downwardly projecting arms (12) to define a cavity to receive the outer surface of the at least one upstanding wall adjacent the opening and biasing means to bias the pair of arms towards one another. The biasing means includes a ring member (24) or disc engageable in an upwardly directed cavity defined by at least one pair of upwardly projecting arms (19), the ring member (24) or disc dimensioned to urge the arms (19) outwardly to in turn urge the arms (12) inwardly. Inwardly directed claws of the arms (12) engage under a flanged portion (6) of the upstanding wall whereby the closure is captured about the neck (2) of the container. A sealing means (15) seals against the inner surface of the upstanding wall, being urged into sealing engagement by downward and outward movement of a diaphragm constituting the top (8). In an alternative arrangement the downwardly projecting arms (12) and sealing means (15) are urged towards one another by means of a ring member engaging in an upwardly directed cavity defined by upwardly projecting outer and inner arms located above and adjacent the downwardly projecting arms and sealing means, the ring member dimensioned to urge the upwardly projecting outer and inner arms respectively outwardly and inwardly to in turn urge the downwardly projecting arms and sealing means respectively inwardly and outwardly.

Description

REUSABLE CLOSURE

FIELD OF THE INVENTION

The present invention relates to a closure for containers. In particular, the closure is adapted to be connected to a container having a neck which defines an opening through which the contents of the container may be dispensed. In one form, the closure is reusable.

BACKGROUND TO THE INVENTION

Closure caps for containers serve many basic non-aesthetic functions. The primary function is to prevent the contents of the container from spilling or otherwise escaping from the container. Another primary function in the case of some beverages, is to preserve carbonation of a liquid in the container.

Many types of closures have been proposed for containers ranging from mechanical sealing devices to chemical based seals. The latter, being reliant upon a chemical seal, is not readily or reliably adapted for reuse as the chemical bonding becomes ineffective after a few reuses. The invention is concerned with the former type of closure relying principally upon mechanical means to retain the closure in position to prevent the contents of the container from being dispensed and/or to create a liquid seal or to retain the contents of the container under pressure. In this specification, the reference to "seal" or "sealing means" will be understood to be equally a reference to the ability to close an opening and/or to create, for example, a liquid or gas seal.

One prior type of such mechanical seal closure is the common plastic cap which has a sealing top designed to sit across the opening in the container and an expandable resilient skirt. When applying the closure to a container the skirt is forced over the neck of the container until the neck contacts the underside of the sealing top. The neck usually has an enlarged part near the opening and an undercut which is engaged by the skirt. The closure is quite effective for non-carbonated beverages but is ineffective to prevent loss of carbonation from liquids upon reuse.

The present invention therefore set out to find a mechanical seal for a container capable of providing a strong and tight seal and useable with containers housing carbonated and non- carbonated beverages. Indeed, it is an object of the invention to provide a closure which has generally improved sealing properties to prior mechanical closures, is simple to manufacture and easy to install and remove. There have been many previous attempts to find a closure capable of fulfilling these functions, however, surprisingly it has now been found that the provision of a closure with downwardly projecting arms which define a cavity to receive the outer surface of the wall of a container and biasing means to bias the pair of arms towards one another has resulted in a closure with superior sealing properties when compared to the prior art.

The advantages of this invention can be highlighted by a comparison with the prior art. For example, AU 488194 discloses a seal which comprises a tearable annular ring which can be used to force the arms of a skirt together. This patent discloses a snap fit only. There is no disclosure of biasing means. AU 51721/64 provides the use of a seal which is concave and pushed down to a flat position to force a seal inside the neck of the container. There is no disclosure of arms defining a cavity to receive the wall and again there is no disclosure of biasing means to move the arms together. AU 57847/69 discloses a seal formed/reinforced by gases in a carbonated beverage. It is a positive requirement of that invention that gas pressure from within the container deforms and causes the closure to be urged into engagement. The higher the pressure the greater the reinforcement of the seal. The present invention requires no internal pressure to achieve a superior seal. AU57847/69 discloses the use of a disc in Figures 5 and 6 which expands under pressure to cause the disc to press an internal secondary bead against the bottle. There is no disclosure, however, of biasing means to bias any downwardly projecting arms towards each other.

GB 1,378,591 uses the downward motion of a second component over a cap to pull a first component downwardly to seal the first component on the neck of a container. The first component is urged downwardly and the sealing surface moves upwardly to engage the annular zone of the container neck. While there is a radially inward movement this is by virtue of the downward motion of the second element and not a biasing of the arms. DE 3122982A1 discloses an annular ring which pushes or holds the inner or outer wall against the neck top. Again there is no biasing of the arms. A further attempt at providing a cap for a container closure is disclosed in AU-A-61179/90. This specification purports to be a resealable cap for carbonated beverages. The cap has a press-top with a skirt to effect the sealing engagement. There is no disclosure of the use of a biasing means to effect the seal of the top on the container.

US 4,369,892 discloses a closure system for a container made of flexible and resilient material comprising a lid engaging the finish of the container and an expansion means such as a toggle pressure ring pressing a sidewall of the lid outwardly against the finish of the container to lock and seal the lid on the container. The expansion ring urges the inner wall outwardly and into engagement with the inner wall of the container, however, fundamentally, there is no biasing of the exterior arms towards each other. A similar type of seal is also disclosed in US 5,271,518 which discloses the use of a seal in the unrelated field of sump covers. Again, a ring is used to reinforce the seal by pushing the inner walls of the container outwardly.

US 4,002,516 discloses a hermetic closure useable with a can lid. The closure has a hinged annular ring. The wall of the container is not enveloped as is the case with the present invention and therefore there is no positive sealing by moving the arms.

SUMMARY OF THE INVENTION

According to the invention, there is provided a closure for an opening in a container defined by at least one upstanding wall having an inner and an outer surface, the closure including:

(a) a top to cover the opening;

(b) sealing means connected to the top and including at least one pair of downwardly projecting arms to define a cavity to receive the outer surface of the at least one upstanding wall adjacent the opening; and

(c) biasing means to bias the pair of arms towards one another.

The invention takes advantage of the translation of the forces created by the biasing means. In one embodiment, the cavity between the arms loosely approximates the opening in the container and the biasing means urges the arms which are in contact or closely approximating the outer surface of the wall into sealing engagement with the wall of the container. It is the use of the biasing means to urge the arms towards each other and the harnessing of the associated inward forces which achieves the superior sealing properties of the closure when compared to prior attempts.

In a preferred form of the invention, the arms of the sealing means include an inner sealing surface which together define a second cavity to receive both the outer and the inner surfaces of the upstanding wall adjacent the opening. In this form of the invention, the addition of the inner sealing surface creates a further means to seal the container. In this form of the invention, rather than the cavity extending across the entire diameter of the opening in the container between the downwardly extending arms, second cavities are created which approximate the width of the wall and sit about the width of the wall.

In yet a further preferred form of the invention, the biasing means biases the arms and the inner sealing surfaces towards one another. In this form of the invention, the sealing surfaces are themselves biased towards the arms to further improve the sealing qualities of the closure . In this way, the arms and the inner sealing surfaces are each urged towards the wall of the container to provide gripping internal and external forces on the wall.

The arms and/or sealing surfaces may preferably have additional sealing means projecting into the first and/or second cavity. The additional sealing means can be included to improve the sealing properties of the closure . Even more preferably, the additional sealing means is at least one finger-like projection to seal and be compressed against the upstanding wall. In other preferred forms of the invention, the additional sealing means is a skirt-like ring. The skirt-like ring is particularly advantageous when the container houses a liquid.

According to another preferred form of the invention, the sealing means includes at least one pair of upwardly projecting arms located above and adjacent the downwardly projecting arms which define an upper cavity to receive the biasing means. In this form of the invention, preferably the biasing means, when located in the upper cavity, moves the upper projecting arms away from each other which in turn urges the downwardly projecting arms towards each other. The biasing occurs about a pivot point often equidistant (though not necessarily) between the upwardly and downwardly extending arms. The urging of the upward arms outwardly and the downward arms inwardly may be considered by some skilled addressees to be a cantilevering effect. Preferably, in this form of the invention, the biasing means has a width greater than the width of the upper cavity. The greater width forces the upper cavity outward effecting the biasing of the downwardly projecting arms inwardly. Like the downwardly projecting arms, the upper projecting arms each preferably include a second engaging surface which together each define second upper cavities. In one preferred form of the invention, the biasing means includes a projection having a width greater than the width of the second upper cavities. In this form of the invention, the projection pushes the walls of the cavities outwardly.

Commercial forms of this invention will preferably require the sealing means and the biasing means to have complementary shapes or forms which have a neat look. In one preferred form of the invention, the sealing means includes means to receive the biasing means in a snap fit. In this form of the invention, the biasing means may include an aperture to receive, for example, a tooth-like projection from the sealing means or vice versa. Alternatively or in addition, the sealing means may include a downward exterior projection which traps a complementary aperture on the biasing means.

In yet further preferred forms of the invention, the closure includes secondary biasing means to bias the inner sealing surfaces towards the downwardly projecting arms. This form of the invention may operate, for example, where the primary sealing means does not operate to bias the inner sealing surfaces or where further means are required to bias these surfaces into engagement with the walls of the container. More preferably, the biasing of the sealing surfaces is achieved by including a deformable diaphragm extending between the sealing surfaces below the opening and secondary sealing means to urge the diaphragm into engagement with the sealing surfaces and to bias the secondary sealing surfaces towards the arms. In a most preferred form, the top functions as the deformable diaphragm. In another preferred form, the secondary sealing means is connected to the biasing means and preferably the secondary sealing means is at least one projection. In this form of the invention, when the biasing means is rotated into contact with the sealing means, the projection(s) which form the secondary sealing means are also brought into contact with, for example, the deformable diaphragm or top.

Preferably, the closure further includes a connecting member connecting the biasing means to the top. This prevents the biasing means from being separated from the top and possibly lost. The closure is preferably formed of plastic material (such as polyethylene terephthalate or polypropylene) or any other suitable material. If desired the entire closure can be a continuous formation created by conventional fabrication methods such as injection moulding.

DESCRIPTION OF THE DRAWINGS

In order that the invention may be fully understood there shall now be described by way of non-limiting example only preferred embodiments of the present invention, the description being with reference to the accompanying illustrative drawings, in which:

Figure 1 is a perspective view of a container with a closure according to one form of the invention;

Figure 2 is a perspective view of the closure of Figure 1 at the first opening stage;

Figure 3 is a perspective view of the closure of Figure 1 at the second opening stage;

Figure 4 is a perspective view of an alternate closure of Figure 1 at the second opening stage;

Figure 5 is a perspective view of the closure of Figure 1 at an optional removal stage;

Figures 6 to 8 are cross-sectional views of the closure of Figure 1 in various stages of being fitted to the opening in the container;

Figure 9 is an enlarged view of the closure of Figure 8;

Figure 10 is a side view of the closure of Figure 1 when fitted to the container;

Figure 1 1 is a cross-sectional view of another container with a closure according to another form of the invention;

Figure 12 is an enlarged cross-sectional view of area "A" of Figure 1 1 ;

Figure 13 is a partial assembly sequence of fitting the closure of Figures 1 1 and 12;

Figure 14 is a perspective view of the closure of Figures 11 to 13 in an open position; Figure 15 is a cross-sectional view of another closure according to the invention;

Figure 16 is a cross-sectional view of a further closure according to the invention;

Figure 17 is a perspective view of another form of a closure with a shaped closure cover;

Figure 18 is a perspective view of the closure of Figure 17 with the closure in an open position;

Figure 19 is a perspective view of another form of the invention having a tamper evident ring-pull; and

Figure 20 is a perspective view of an alternate form of a closure according to the invention.

In the drawings, like numbers refer to like features in each of the Figures.

Figures 1 to 5 show the opening sequence of a closure in accordance with the invention. Figures 6 to 8 show the closure of Figures 1 to 5 in more detail.

Container 1 has a neck 2 defined by a wall 3. Closure 4 extends across the opening 5 defined by wall 3. Container 1 has a flanged portion 6 adjacent the opening and a skirt 7 below flange 6. Flange 6 has a sloping surface. Closure 4 has a top 8 which substantially covers the surface of the container 1, a biasing cap 9 attached by a deformable flexure or hinge 10 to the sealing member 11. Biasing cap 9 functions as a secondary top by also covering the opening of the container 1. Sealing member 11 has a plurality of downwardly projecting arms 12 extending about the opening 5 in a crown formation which each have an inwardly projecting foot 14. The arms 12 are separated as a split pleat or segmented design to enhance the flexibility of closure 4. Located opposite arms 12 are sealing surfaces 15 which are attached at their lower ends to the top 8 which is shaped as a convex deformable diaphragm. The arms 12 together with the sealing surfaces 15 form a cavity 16 which as discussed below is destined to receive the flange 6. A nose 17 projects from the top 8 and has a series of holes 18 which serve the function in, for example, containers housing carbonated drinks to assist in the release of gas pressure and also to allow the contents of the container 1 to exit the container 1 in use. The sealing member 8 has a plurality of upwardly extending arms 19 adjacent the downwardly projecting arms 12. The arms 19 extend above the opening 5 in container 1 and form an upper cavity 32. Skilled addressees will understand that in certain forms of the invention, the upwardly extending arms 19 need not extend above the opening 5 in the container 1. For example, where the container includes a spout, the biasing cap may extend over the spout, however, the upward arms (while extending above the downward arms) need not extend above the opening. The member 11 has an outwardly extending portion 13 on arm 19A which includes a smaller downwardly projecting arm 20 and either an upstanding knob 21 (as shown in Figures 1 to

3 and 5) or an aperture 22 (as shown in Figures 4 and 6 to 8).

Biasing cap 9 is hingedly attached to the member 11 and has an inner downwardly projecting cylinder portion 23 and an outer downwardly projecting ring 24. It further includes an outward projecting portion 25 with a downwardly projecting arm 26 having an inwardly projecting foot 27 and either an aperture 28 or a downwardly projecting smaller arm 29. Smaller arm 29 has a foot 33 at its end.

With reference to Figures 1 to 5 the opening sequence involves lifting the biasing cap 9 and rotating it about hinge 10. If the contents of the container 1 are carbonated then for safety reasons, the biasing cap 9 can be partially opened to allow the release of pressure and then opened more fully. For example, in one form of the invention, the downwardly projecting arm 26 can be initially disengaged from arm 20 on portion 13 of arm 19A to allow some release of the pressure. The smaller arm 29 can then be disengaged from aperture 22 and then the biasing cap 9 removed from within the ring 24. The holes 18 also assist in the pressure release. The partial or gradual release of the pressure can help prevent the closure

4 from being released too quickly. It will be understood that the closure 4 will still operate with, for example, carbonated beverages without the need for holes 18. By continuing the pull up, biasing cap 9 is disengaged from the top 8 and then disengaged from the neck 2. Reversal of the opening sequence will reinstall the closure 4.

As shown in particular detail in Figures 6 to 8, in operation, sealing member 11 is initially attached to container 1 by an interference fit. Arms 12 are pushed down about the outer surface of flange 6. Feet 14 are trapped below the flange 6. The sealing surfaces 15 are received in sealing engagement with the inner surfaces of flange 6. In Figure 6, top 8 is shown in the fully open position. To seal the container 1, the top 8 is swung about the hinge 10 as shown in Figures 7 and 8. Biasing cap 9 is secured in the closed position to member 11 in a number of ways. Foot 27 of arm 26 is received in a snap fit over downwardly projecting arm 20 and either aperture 28 or arm 29 of biasing cap 9 are received in upstanding knob 21 or aperture 22 respectively to enhance the engagement. Upon the snap fit of the biasing cap 9 on member 11, the container is sealed by outer ring 24 being received in a tight fit against upwardly extending arms 19. The arms 19 can have a lead angle (an outward incline) to enable the outer ring 24 to be more easily received in the cavity 32. The hinge or flexure 10 must be of a sufficient length to enable the outer ring 24 to be adjusted and readily positioned within the upper arms 19 of sealing member 11. The tight fit forces arms 19 to pivot outwardly about pivot point 30 which in turn biases downwardly projecting arms 12 towards each other and into engagement with flange 6 of container 1. The sloping surface of flange 6 is designed to provide a recessed area into which the arms 12 are biased. In this way the sealing member 11 is captured in a tight fit about the neck 2 of the container 1.

As a further measure to seal the container 1, the inner cylinder 23 of biasing cap 9 engages top 8 (in the form of a diaphragm) of member 11 forcing it downwardly and outwardly. The outward motion forces sealing surfaces 15 into engagement with the inner surfaces of flange 6 creating an inner or secondary seal. This secondary seal is particularly advantageous when the contents of the container are carbonated as the additional secondary seal assists in maintaining the carbonation. Inner cylinder 23 also has the additional advantage of creating a sealing engagement about the nose 17.

In order to fully understand the operation of the force moments that operate in creating the superior sealing mechanism of this invention, lines depicting the operation of the forces have been included in Figure 9 as a series of arrows. Outer ring 24 has a slightly greater diameter than the diameter of the upwardly extending arms 19. Accordingly, the downward moment of ring 24 (A) is transferred into an outward force (B) on upward arms 19. Arms 19 on extending outwardly pivot about pivot point 30 to force downwardly projecting arms 12 inwardly (C) and into engagement with the flange portion 6 of the neck 2 of container 1. The downward motion of the inner cylinder 23 (D) on contact is transferred to top 8 (E) which in turn has the effect of stretching sealing surface 15 downwardly and inwardly (F) and (G) to effect a tighter seal of the surface 15 against the inner surface of flange 6. Figures 11 to 13 show a different form of the invention. In these Figures, the container 40 has a neck 41 defined by a wall 42. Container 40 has an opening 43. In this form of the invention the container need not have a flange near its opening. Closure 44 has a top 45 and downwardly extending arms 46. The arms are arranged in a split pleat or segmented design (as shown in Figure 14) to again enhance the flexibility of the outer arm (not shown). -Arms 46 have an outer claw 48 and an inner claw 49 at their distal ends which are destined to sit about the outer and inner surfaces of the wall 42 adjacent to the opening 43. The claws define a downward cavity 48. Upwardly extending arms 51 extend above the opening 43 and adjacent the downwardly projecting arms 46. A biasing cap 55 is attached by a flexible hinge 47 to closure 44 about one of the upwardly extending arms 51 which has outer and inner claws 52 and 53 which define an upper cavity 54. The biasing cap 55 has an annular rib 56.

As more particularly shown in Figures 12 and 13, the wall 42 is aligned with the annular cavity 50 in step I. The cavity 50 has a narrowed opening whilst the wall 42 has an edge rib so that the cavity opening is slightly more narrow than the thickness of the edge rib. The insertion of the wall 42 into the cavity 50 is a snap fit partial seal as shown in step II. The cavity 50 has additional seal 57 (in the form of a skirt-like ring) formed on its inner surface to enhance the overall seal.

In operation as shown in Figure 13 and in particular step III, annular rib 56 has a thickness which is greater than the opening of cavity 54. As the rib 56 enters the cavity 54, it forces the outer and inner claws 52 and 53 of upwardly extending arms 51 apart which by a biasing motion about pivot point 58 forces the outer claw 48 and inner claw 49 of downwardly extending arms 46 towards one another to reinforce the sealing contact with the edge rib of wall 42. This movement also reinforces the contact of additional seal 57 with the wall 42. The rib 56 is not exactly complementary with cavity 50 and as such the arms 46 rotate relative to the rib 56 to establish areas of sealing contact when the biasing cap 55 is closed.

Like Figure 9, arrows depicting the operation of the force moments have been included to show in further detail the principle of this form of the invention in Figure 13. The downward moment of annular rib 56 (A) is transferred into an outward force (B) on upwardly extending arms 51 causing outer claw 52 and inner claw 53 to move outwardly and away from each other. The outward motion of claws 52 and 53 pivot outer and inner claws 48 and 49 downwardly extending arms 46 towards each other (C) about pivot point 58.

The progressive release of the closure 44 (where, for example, the contents of the container 40 are carbonated) can be very easily achieved with the closure depicted in Figures 11 to 14. The segmented skirt and outer and inner claws 48 and 49 of downwardly projecting arms 46 can be sequentially released in a zipper-like fashion to allow the slow release of the carbonation. Again the breathing hole 59 operates to allow carbonation to escape.

The top 45 can have a "breathing hole" 59 as shown in Figure 1 1 or a plurality of openings 60 shown in Figure 14 to allow the closure to be used for dispensing paniculate material like pepper and salt. Obviously, in such applications the biasing cap 55 serves to seal the contents of container 40 from the spillage.

Two further forms of the invention are shown in Figures 15 and 16. In Figure 15, the upwardly extending arms 51 have a stepped interior surface 61. The seal 62 has a complementary shape to the stepped surface 61 and when in position forces the upwardly extending arms 51 out. This in turn reinforces the seal about wall 42. The locking of the arms in this form of the invention is simile to that shown in Figures 6 to 8 with the inner sealing surface 66 being apt to be used as a gas seal. In Figure 16, the upwardly extending arm 51 has an inward extension 63 to form a cavity 64. A rigid ring 65 is wedged under the extension 63 forcing it up and thereby reinforcing the seal about wall 42. This is also an example of where no secondary seal is required inside the container.

Figures 17 to 20 show further practical variations of the invention. Figures 17 and 18 show a variation on the closure 4 shown in Figures 1 to 10. In these figures, the closure 4 has an enlarged spout 31. The shape of the biasing cap 9 is similarly altered to take account of the shape of the spout 31. In this form of the invention, there is no inner cylindrical portion 23. Figure 19 shows the integration in the form of the closure depicted in Figures 11 to 13 of a tamper proof seal 67 with closure 44, between the top 45 and the biasing cap 55. This type of seal can similarly be integrated with other forms of the invention. This seal 67 is removed to allow the closure to operate as described above. Figure 20 depicts the use of the closure of the invention when used in respect of an irregular shaped container 40. The upwardly extending arms 51 are a segmented skirt similar in design to that shown in Figure 19. A tamper-proof seal 67 also acts as described in Figure 19.

While the closure of this invention can be used to close, for example, containers which house food and drinks, the types of containers to which the invention has application is limitless. For example, the invention could be used to provide a closure for a violin case or other such casings. The invention has application to regular and irregular shaped containers.

It is to be understood by those skilled in the technology that many variations or modifications in details of design or construction may be made without departing from the essence of the present invention. Therefore, the invention should be understood to include all such variations and modifications within its scope.

Claims

THE CLAIMS DEFINING THE INVENTION ARE AS FOLLOWS:

1. A closure for an opening in a container defined by at least one upstanding wall having an inner and an outer surface, the closure including:

(a) a top to cover the opening;

(c) biasing means to bias the pair of arms towards one another.

2. The closure of claim 1 , wherein the arms include an inner sealing surface which together define a second cavity to receive both the outer and the inner surfaces of the at least one upstanding wall adjacent the opening.

3. The closure of claim 2, wherein the biasing means biases the arms and the inner sealing surfaces towards one another.

4. The closure of claim 1, wherein the arms have additional sealing means projecting into the first cavity.

5. The closure of claims 2 or 3, wherein the arms and/or sealing surfaces have additional sealing means projecting into the second cavity.

6. The closure of any one of claims 4 or 5, wherein the additional sealing means is at least one finger-like projection to seal and be compressed against the upstanding wall.

7. The closure of any one of claims 4 or 5, wherein the additional sealing means is a skirt-like ring to seal and be compressed against the upstanding wall.

8. The closure of any one of claims 1 to 7, wherein the sealing means includes at least one pair of upwardly projecting arms located above and adjacent the downwardly projecting arms, the upwardly projecting arms defining an upper cavity to receive the biasing means.

9. The closure of claim 8, wherein the biasing means, when located in the upper cavity, moves the upper projecting arms away from each other which in turn urges the downwardly projecting arms towards each other.

10. The closure of claim 9, wherein the biasing means has a width greater than the width of the upper cavity.

1 1. The closure of claim 8, wherein the upper projecting arms each include a second engaging surface which together each define second upper cavities.

12. The closure of claim 9, wherein the biasing means includes a projection having a width greater than the width of the second upper cavities.

13. The closure of any one of claims 1 to 12, wherein the sealing means includes means to receive the biasing means in a snap fit.

14. The closure of any one of claims 2, 3 and 4 to 13, including secondary biasing means to bias the second arm towards the first arm.

15. The closure of claims 2, 3 and 4 to 14, including a deformable diaphragm extending between the sealing surfaces and below the opening and secondary sealing means to urge the diaphragm into engagement with the sealing surfaces and to bias the sealing surfaces towards the arms.

16. The closure of claim 15, wherein the top is the deformable diaphragm.

17. The closure of claims 15 or 16, wherein the secondary sealing means is connected to the biasing means.

18. The closure of any one of claims 15 to 17, wherein the secondary sealing means is at least one projection.

19. The closure of any one of claims 1 to 18, wherein the closure further includes a connecting member connecting the biasing means to the top.