WO1999028205A1

WO1999028205A1 - Tamper-evident container closure

Info

Publication number: WO1999028205A1
Application number: PCT/AU1998/000997
Authority: WO
Inventors: Christopher Lyndon Higgins; Liam Stephen Irwin; Peter William Brown; Robert Mcfadyen
Original assignee: C.T.E.B. Equipment Pty. Ltd.
Priority date: 1997-11-28
Filing date: 1998-11-30
Publication date: 1999-06-10
Also published as: AUPP062897A0

Abstract

A tamper-evident and optionally child-resistant closure (1) for application to a container neck (8) includes inner (2) and outer (3) components both of which comprise respectively a top wall (4, 13) and a peripheral skirt (5, 14) for both rotational and axial movement of the outer component (3) relative to the inner component (2). Rotation of the closure (1) in the anti-clockwise direction, as in opening the container, causes breakage of frangible bridge members (15) which join the outer peripheral skirt (14) to the top wall (13) whereupon the outer peripheral skirt (14) moves downward relative to the inner peripheral skirt (5) to reveal the colour of the inner component (2) through a gap (22), the presence of which indicates that the container has previously been opened or that the closure has been tampered with. The closure (1) optionally also includes a child-resistant feature requiring the outer peripheral skirt (14) to be squeezed out of round at predetermined points to cause engagement between lugs (26, 27) allowing rotation of the inner and outer components (2, 3) in unison for opening of the container.

Description

TAMPER-EVIDENT CONTAINER CLOSURE

TECHNICAL FIELD

The present invention relates to tamper-evident closures and more particularly relates to an improved closure allowing visual colorimetric indication of tampering. In a preferred form, the invention also relates to tamper-evident child-resistant closures.

The closure according to the present invention includes an inner and outer component both of which comprise respectively a base wall and peripheral skirt for both rotational and axial movement of the outer component relative to the inner component. In addition, both the inner and outer components may move together depending upon the direction of turning of the closure and extent of applied torque. The invention achieves the above without the need for special complimentary features of the container and the consequent problems of control of tolerances/clearances which may adversely affect the performance of the closures.

BACKGROUND ART

There are already in existence a wide variety of child resistant closures of the type comprising an outer shell having a base wall and a peripheral skirt and an inner shell having a base wall and a peripheral skirt. One such arrangement is described in British patent 1529999. The inner shell in that closure includes threads on an inner surface adapted to engage threads on a container. The outer component has a series of radial projections on its wall which engage corresponding projections on an outer surface of the shell. This particular device suffers from the problem that the closure is not user friendly in that the amount of axial force required to remove the closure is dependant upon the interengagement of the size of the projections to provide the necessary breakaway torque necessary to loosen the closure.

Another arrangement is described in Australian Patent 624762 which sought to improve the arrangement in British patent 1529999 by providing means by which a closure having an outer and inner component can be removed either by tilting of the outer shell relative to the inner shell or by axial movement only of the outer shell relative to the inner shell. The arrangement further includes an inclined surface on the inner surface of the outer shell extending radially at an acute angle to the plane of the base wall of the outer shell such that when the outer shell is tilted in the direction of the inclined surface the lugs projecting from the inside surface of the base wall of the outer shell engage grooves in the outer surface of the base wall of the inner shell allowing the inner shell to be unscrewed from the container on which the closure is provided and such that the closure can be also operated by moving the outer shell axially with sufficient force towards the inner shell to engage the projections. Whilst this arrangement works, a reasonable degree of axial force is still required to remove the closure.

Australian patent 656851 also discloses a child resistant reminder closure comprising outer and inner closures members having respectively a base wall and a peripheral skirt with means on the outer closure member retaining the inner closure member against axial outward movement relative to the outer closure member. This device further comprises an indicator disc having an opening on the outer surface of the base wall of the inner shell allowing the inner shell to be unscrewed from the container on which the closure is provided and such that the closure can be also operated by moving the outer shell axially with sufficient force towards the inner shell to engage the projections. Whilst this arrangement works, a reasonable degree of axial force is still required to remove the closure.

Australian patent 656851 also discloses a child resistant reminder closure comprising outer and inner closures members having respectively a base wall and a peripheral skirt with means on the outer closure member retaining the inner closure member against axial outward movement relative to the outer closure member. This device further comprises an indicator disc having an opening on the outer surface of the base wall of the inner closure member which is rotatable relative to the outer and inner closure members. The outer closure member and inner closure and indicator disc are constructed and arranged to maintain engagement of the indicator disc with the outer closure member and the inner closure member wherein the indicator disc has indicia visible through the window to indicate the circumferential position of the indicator disc relative to the outer closure member. Whilst this device functions quite well, it does not have a frangible bridge which allows for easy fracturing to indicate tampering. Another child resistant closure arrangement is disclosed in Australian patent 47291/96 and comprises an inner closure part having an internal screw thread for screw threading engagement with a neck of a container and an outer closure part retained on the inner closure part with a first set of castellations do not engage unless an axial compressive force is applied between the inner and outer parts. Whilst this arrangement involves an inner and outer closure it does not teach visual identification of tampering with a colorimetric indicator.

There are other arrangements described in prior art specifications having an outer and inner components both with a wall and peripheral skirt with interact to provide a child resistant closure for sealing an opened topped container having an external screw thread formed on a neck finish of the container. Examples of these can be found in Australian applications 65711/96, 26367/84,53245/86, and patents 616613 and 622583.

United States patent 5829611 discloses a tamper-evident cap and overcap for containers such as beverage containers for mineral water, sports drinks, syrups or the like, or for shampoo, soaps and other comestibles wherein the removal of the overcap revealed an underlying portion of the cap of a colour different to that of the overcap. However this tamper-evident cap is designed such that the overcap can be re -fitted to the container to protect the underlying portion of the cap when not in use.

However, none of these documents disclose in combination a closure comprising an inner and outer component wherein a peripheral skirt on the outer component is joined via a bridge to a base wall in which fractures on a degree of rotation reveal a colorimetric indicator of tampering and in combination with the feature of child resistance. Thus it is not found in the prior art to provide in combination a closure having a drop down skirt and squeeze knurls for operation of a child resistant feature. DISCLOSURE OF THE INVENTION

It is an object of the present invention to provide a tamper-evident closure for a container which goes at least some way towards overcoming or at least minimising the prior art problems or limitations outlined above.

It is another object of this invention to provide a tamper-evident and optionally also child- resistant closure which is universally adaptable for use with a variety of containers, and which includes an added tamper evident characteristic which becomes highly visible at the first removal, or attempted removal, of the closure.

It is a further object of this invention to provide a means of converting a standard closure for a container to a tamper-evident and optionally also child-resistant closure by fitment of an overcap to the standard closure wherein the overcap includes a tamper evident characteristic which becomes highly visible at the first removal, or attempted removal, of the closure and the overcap.

It is yet another object of the present invention to provide a tamper-evident and child resistant closure which is relatively simple in construction and relatively inexpensive to manufacture.

These and other objects of this invention will become more apparent from the following descriptions and the drawings.

According to one aspect of the present invention, there is provided a tamper-evident closure for application to a container neck comprising a wall and a depending peripheral skirt adapted for attachment as an overcap to a conventional screw threaded container closure which is threadably attached to the neck of a container, the overcap is attachable to the container closure such that the overcap is allowed to rotate with or relative to the container closure at least to a limited extent, said overcap including a frangible bridge member or members which join the peripheral skirt of the overcap to said wall of said overcap, such that rotation of the overcap and the underlying container closure in the anti-clockwise direction causes the bridge member(s) to break, whereupon said peripheral skirt of said overcap moves downwards relative to the underlying container closure to reveal the colour of the container closure through a gap formed after breakage of said bridge member(s) between the peripheral skirt and the wall of the overcap.

According to a further aspect of the present invention, there is provided a tamper-evident closure for application to a container neck comprising an inner component having a wall and a depending peripheral skirt threaded so as to be threadably attached to the neck of the container, and an outer component having a wall and a depending peripheral skirt which surrounds the peripheral skirt of the first component, and wherein the said outer component is either attached to or is attachable to the inner component such that said outer component is allowed to rotate with or relative to the inner component at least to a limited extent, said outer component including a frangible bridge member or members which join the peripheral skirt of said outer component to the wall of said outer components, such that rotation of the closure in the anti-clockwise direction causes the bridge member or members to break whereupon said peripheral skirt of the outer component moves downwards (e.g. under gravity) relative to the peripheral skirt of the inner component through a gap formed after breakage of said bridge member(s) between the peripheral skirt and wall of the outer component.

According to another aspect of the present invention, there is provided a tamper-evident child-resistant closure for application to a container neck said closure comprising; an inner component having a wall and a depending peripheral skirt threaded so as to be threadably attached to the neck of a container; an outer component having a wall and a depending peripheral skirt which surrounds the peripheral skirt of the first component; means on said outer component engaging with an undercut on said inner component so as to retain said outer component against said inner component but allowing said outer component to rotate with or relative to the inner component at least to a limited extent; said inner component including projections of an outer surface of the peripheral skirt of the inner component which engage corresponding projections on an inner surface of said outer component to prevent relative movement between said inner and outer components; a frangible bridge member or members which join the peripheral skirt of the outer component to said wall of said outer component such that rotation of the closure in the anti-clockwise direction causes said bridge member or members to break whereupon said peripheral skirt of said outer components moves downwards relative to the peripheral skirt of the inner component to reveal the colour of the inner component through a gap formed after breakage of said bridge member/s between the peripheral skirt and wall of the outer component.

Ideally, in all embodiments of the invention the top wall of the outer component or overcap remains attached to the top wall of the underlying container closure or inner component after separation from the peripheral skirt of the outer cap or overcap. This may be ensured by welding or other equivalent means.

BRIEF DESCRIPTION OF THE ACCOMPANYING DRAWINGS The present invention will now be described in more detail according to a preferred but non limiting embodiment and with reference to the accompanying illustrations wherein: Figure 1 : shows a part cross sectional profile of the closure arrangement according to a preferred embodiment of the invention; Figure 2: shows the arrangement of figure 1 this time manifesting the tamper evidencing facility wherein the peripheral skirt of the outer component is separated from its corresponding base wall; Figure 3: shows an elevation view of a profile of the inner component absent the outer component; Figure 4: shows a plan view of the arrangement of figure 3; Figure 5 : shows an elevation view of the outer component of the closure according to a preferred embodiment; and Figure 6: shows a plan view of the closure arrangement of figure 5. Referring to figure 1 there is shown a part cross sectional view of a closure according to a preferred embodiment of the invention. Closure 1 comprises inner component 2 surrounded thereabout by outer component 3 which interacts and cooperates in the manner described below.

Inner component 2 comprises a top wall 4 and a downwardly depending peripheral skirt 5 including a formation 6 which engages corresponding threaded formations 7 of the neck portion 8 of a container 9. The closure is applied to container 9 which may be a bottle or the like made of plastics or glass material by rotating the closure in a generally clockwise direction in a universal manner. Inner component 2 includes an undercut 10 forming a recess 11 into which profile part 12 of outer component 3 nests. This ensures that the top wall 13 of outer component 3 does not separate from inner component 2 (particularly after fracturing of bridge elements 15 described below) but is free to rotate with or relative to inner component 2. The stepped up portion of outer component 3 allows for transfer of any top load on the cap through the sidewall of top wall 13 to the neck 8 of bottle 9. Upon assembly of the components 2 and 3 profile feature 30 on outer component 3 engages profile part 29 on the inner component 2 thus preventing actual separation of the inner and outer components 2 and 3 respectively. Outer component 3 comprises a downwardly depending peripheral skirt 14 which is connected to top wall 13 via bridge element 15. Bridge element 15 comprises a frangible connection and these may be spaced intermittently circumferentially around the closure in numbers according to the degree of strength of the connection required between peripheral skirt 14 and top wall 13. When closure 1 is applied to container 9, inner and outer components 2 and 3 respectively rotate together until such time as the required application torque is reached. Drive lugs 16 transfers the application torque from the outer component 3 to stop lugs 17 on inner component 2. Once the closure is set in position on container 9, removal of the closure or manifestation of tamper evidence requires rotation of the closure in an anti-clockwise direction. In this case lugs 18 contact stop members 19 when the closure is rotated in the anti-clockwise direction. Stop means 19 on the inner component prevent the rotation of the outer closure as anti-clockwise torque is increased. This causes bridges 15 to undergo shear failure thereby separating depending skirt 14 from base wall 13 of outer component 3. In a further embodiment (not shown) the top wall can be permanently affixed to the corresponding top wall of the inner cap (4) by spot welding or the like. The frangible bridges 15 may also be broken, by means of downward force applied to the peripheral skirt 14.

Figure 2 shows the embodiment of figure 1 this time with bridging member 15 fractured such that downwardly depending skirt 14 moves in a generally downward or axial direction relative to inner component 2 in the direction of arrow 20. Figure 2 has been assigned numerals corresponding to the same components described in figure 1. Once fracturing of bridge 15 has taken place, a gap indicated by arrow 22 is created allowing visual contact with surface 23 of inner component 2. Inner component 2 is coloured so that as soon as the inner component colour is visible, this means that the closure has been tampered with. Preferably downwardly depending skirt 14 will drop down under gravity exposing a red colour acting as a warning on surface 23.

Figure 3 shows inner component 2 applied to the upper reaches of the neck of a container. Figure 3 has been numbered with numerals corresponding to those in figures 1 and 2. Figure 3 shows inner component 2 separated from outer component 3 and describes recess 11 providing an undercut to receive protrusion 12 of base wall 13 of outer component 3 ( see figures 1 and 2).

Figure 4 shows a plan view of the inner component 2 shown in figure 3.

Referring to figure 5 there is shown an elevation view of outer component 3 free of inner component 2. Typically outer component 3 which in figure 3 has been assigned numbers corresponding to those assigned in figures 1 and 2 comprises top wall 13 connected by means of bridge 15 to downwardly depending skirt 14. The degree of fracturing torque required to break the peripheral skirt 14 away from the wall 13 will depend upon and can be adjusted according to the total contact length or length of the bridge/s.

Figure 6 shows a plan view of the outer component 3 shown in figure 5. The child resistant feature of the closure operates according to the following regime.. As the skirt 14 of outer component 3 drops in the direction of arrow 20, child resistant lugs 26 which are in an identical vertical plane as child resistant lugs 27 of inner component 2. In order to engage the child resistant lugs in both inner and outer components, outer component 3 is squeezed 180° apart at squeeze knurls 28 ( see figure 5).

Outer component 3 may the be turned anti-clockwise until both sets of child resistant lugs 26 and 27 engage. Further torque will unscrew the inner closure thus removing the two component closure system.

The tamper-evident closure of the present invention is relatively simple in construction to ensure ease of assembly and reliable operation. The component parts are ideally moulded from suitable plastics material, for example by injection moulding.

It will be recognised by persons skilled in the art that numerous variations and modifications may be made to the present invention as broadly described herein without departing from the overall spirit and scope of the invention.

Claims

1. A tamper-evident closure for application to a container neck, said closure comprising a wall and a depending peripheral skirt adapted for attachment as an overcap to a conventional screw threaded container closure which is threadably attached to the neck of a container, wherein the overcap is attachable to the container such that the overcap is allowed to rotate with or relative to the container closure at least to a limited extent, said overcap including a frangible bridge member or members which join the peripheral skirt of the overcap to the wall of said overcap, such that rotation of the overcap and the underlying container closure in the anti-clockwise direction causes the bridge member(s) to break, whereupon said peripheral skirt of the overcap moves downwards relative to underlying containing closure to reveal the colour of the container closure through a gap formed after breakage of said bridge member(s) between the peripheral skirt and the wall of the overcap.

2. A tamper-evident closure for application to a container neck, said closure comprising an inner component having a wall and a depending peripheral skirt threaded so as to be threadably attached to the neck of the container, and an outer component having a wall and depending peripheral skirt which surrounds the peripheral skirt of the first component, and wherein said outer component is either attached to or is attachable to the inner component such that said outer component is allowed to rotate with or relative to the inner component at least to a limited extent, said outer component including a frangible bridge member or members which join the peripheral skirt of said outer component to the wall of said outer component, such that rotation of the closure in the anti-clock direction causes the bridge member(s) to break, whereupon said peripheral skirt of the outer component moves downwards relative to the peripheral skirt of the inner component to reveal the colour of the inner component through a gap formed after breakage of said bridge member(s) between the peripheral skirt and wall of the outer component.

3. A tamper-evident and child-resistant closure for application to a container neck, said closure comprising an inner component having a wall and a depending . peripheral skirt threaded so as to be threadably attached to the neck of a container; an outer component having a wall and a depending peripheral skirt which surrounds the peripheral skirt of the first component; means on said outer component engaging with an undercut on said inner component so as to retain said outer component against said inner component but allowing said outer component to rotate with or relative to the inner component at least to a limited extent; said inner component including projections on an outer surface of the peripheral skirt of the inner component which engage corresponding projections on an inner surface of said outer component to prevent relative movement between said inner and outer components; a frangible bridge member or members which join the peripheral skirt of the outer component to said wall of said outer component such that rotation of the closure in the anti-clockwise direction causes said bridge member or members to break whereupon said peripheral skirt of said outer components moves downwards relative to the peripheral skirt of the inner component to reveal the colour of the inner component through a gap formed after breakage of said bridge member/s between the peripheral skirt and wall of the outer component.

4. A tamper-evident closure as claimed in any one of claims 1 to 3, wherein said wall of said outer component or said overcap is releasably attached to said inner component or container closure after breakage of said bridge members.

5. A tamper-evident closure as claimed in any one of the preceding claims, wherein the inner component or the peripheral skirt thereof is of a colour different to that of the outer component or overcap.

6. A tamper-evident closure as claimed in any one of the preceding claims, wherein when the peripheral skirt of the outer component moves downwards, one or more projections on the inner surface of the peripheral skirt of the outer component are adapted to engage one or more projections on the outer surface of the peripheral skirt of the inner component when the peripheral skirt of the outer component is distorted out of the round by squeezing at opposite sides of said peripheral skirt at predetermined locations preventing relative movement between said inner and outer components and allowing them to be rotated in unison.

7. A tamper-evident closure as claimed in any one of the preceding claims wherein the wall of the outer component is attached to the underlying wall of the inner component.