Piercing system for a sealed package

Abstract

 A cam activated piercing system 1 for a container 2, particularly a container of medicament, such as eye drops. The piercing system comprises an attachment portion 3 which remains stationary with respect to the container 2, a piercing member 4 which can move axially and rotationally within the attachment portion 3 and a closure cap 5 for reclosing the container after use. Complimentary ratchets 6,7 are provided on the attachment portion 3 and piercing member 4. When the closure cap 5 and piercing member 4 are first applied to the container 2, the ratchets 6,7 slip over one another allowing the piercing member 4 to rotate with the closure cap 5. However, when the closure cap is first unscrewed from the container 2, the ratchets 6,7 engage, preventing rotation of the piercing member 4 and the rotation of the closure cap 5 causes axial movement of the piercing member 4 by means of the interaction of the cam arrangement.

Description

[0001] The present invention relates to a piercing system for packages sealed by a frangible membrane and in particular, to piercing systems having a screw cap which engages with a piercing element via a cam arrangement to drive the piercing element through the membrane on first opening of the screw cap.

[0002] This type of cam arrangement has been applied to piercing closures for laminated cardboard containers, such as those used for fruit juices, and is described in EP 0 328 652B1 and WO 99/62776, the subject matter of both of which are included in the present application by way of reference.

[0003] The present invention is particularly suitable for use with sealed containers of medicament, where the closure has to be applied to the filled and sealed container without activating the piercing member.

[0004] Accordingly, the invention provides a piercing system for a package sealed by a frangible membrane, the piercing system comprising an attachment portion having a screw thread defined thereon, a closure cap having a complimentary screw thread, to allow the closure cap and attachment portion to be releasably connected together, and a piercing member arranged to move axially within the attachment portion, the closure cap and piercing member having complimentary cam members, adapted to drive the piercing member towards the membrane when the closure cap is first unscrewed from the attachment portion, characterised in that the attachment portion and piercing member further comprise complimentary ratchets, adapted to slip relative to one another when the closure cap is screwed on to the attachment portion, thereby allowing the piercing member to rotate relative to the attachment portion, but to engage when the closure cap is first unscrewed from the attachment portion, thereby preventing rotation of the piercing member and engaging the cam members to convert the rotational movement of the closure cap into axial movement of the piercing member.

[0005] In the case of a sealed container of medicament, the container may take the form of a bottle having a threaded neck. The threaded neck of the bottle thereby providing the attachment portion of the piercing system. Alternatively, the bottle may be provided with a neck adapted to co-operate with a closure, having a base which forms the attachment portion. The frangible membrane may be provided integral with the bottle or with the base of the closure.

[0006] The ratchet arrangement between the attachment portion and the piercing member is adapted to slip when the closure cap is applied to the container, allowing the piercing member to rotate with the closure cap, preventing activation of the cam members, and thus preventing axial movement of the percing member. This allows the closure to be screwed onto the container without activating the cam arrangement and thereby reduces the risk that the piercing member will accidentally damage the frangible membrane.

[0007] When a user first opens the closure cap, by unscrewing, the ratchet arrangement engages to prevent the piercing member rotating with the closure cap and the cam members engage to convert the rotational movement of the closure cap into axial movement of the piercing member to drive it towards and through the membrane, allowing the contents of the container to be dispensed.

[0008] Preferably the ratchet on one of the attachment portion or the piercing member has a sufficient number of equi-spaced teeth to ensure engagement of the two ratchets when the closure cap is rotated through a relatively small angle during unscrewing of the closure cap. This ensures that the cam members engage as early as possible during unscrewing and the remaining unscrewing motion of the closure cap is sufficient to drive the piercing member through the membrane.

[0009] The ratchet on the other of the attachment portion or piercing member advantageously has two ratchet teeth or projections arranged equidistant around its perimeter (ie spaced at 180º to one another). A single ratchet tooth or projection can lead to alignment problems and although the provision of more ratchet teeth / projections makes the arrangement more stable, it also increases the rigidity of the ratchet, making it more difficult for the ratchets to slip relative to one another, when the closure cap is screwed onto the container.

[0010] Two ratchet teeth / projections ensure that the ratchets remain square to one another and are not cocked, whilst allowing the ratchet to oval slightly when the closure cap is screwed on to the container and the ratchets slip over one another. The provision of more ratchet teeth has been found to inhibit the slip between the ratchets and thereby restrict the rotation of the piercing member with the closure cap.

[0011] Preferably, the frangible membrane is provided by a thinned portion covering the mouth of the container and having a cruciform shaped weakened section defined therein. On piercing, the weakened section breaks, forming a plurality of flaps which can be folded back by the piercing member to provide a dispensing opening. Preferably, the piercing member is provided with three ribs, joined in the centre of the piercing member to form a penetration point. Three ribs are chosen for this embodiment to increase the chance that one rib will lie aligned or adjacent to a line of weakening in the membrane, when the piercing member reaches the membrane. Thus removing the need for accurate alignment between the piercing member and the frangible membrane.

[0012] A prefered embodiment of the invention will now be described, by way of example only, with reference to the accompanying drawings, in which:

Fig.1 shows a side section view of a sealed bottle of medicament equipped with a piercing system according to the invention. The piercing system is shown applied to the bottle, in its closed non-activated position.

Fig.2 shows a side section view of the sealed bottle shown in Fig.1, with the piercing member in its activated position having broken through the frangible membrane.

Fig.3 shows a horizontal section through an isometric view of the piercing system shown in Figs. 1 and 2, looking upwards towards the closure cap.

Fig.4 shows a horizontal section through an isometric view of the piercing system looking downwards towards the bottle.

Fig.5 shows an enlarged view of the ratchet arrangement, indicating the direction of rotation of the closure cap/piercing member as it is screwed onto the bottle of medicament.

Fig.6 shows the same enlarged view of the ratchet arrangement shown in Fig.5, indicating the direction of rotation of the closure cap as it is unscrewed from the bottle for the first time.

[0013] Figs. 1 and 2 illustrate a piercing member 1 according to the invention, affixed to a bottle 2, for containing a medicament such as eye drops, for example. The bottle 2 has a sidewall 21 and a separate base 22. The sidewall 21 defines a neck 25 having an external screw thread 27 defined thereon. The threaded neck 27 thereby forms the "attachment portion" 3 of the invention. The neck 25 is sealed by a frangible membrane 26, integrally moulded with the sidewall 21. The bottle 2 is inverted for filling, with the contents being filled through the open end of the sidewall 21. The base 22 is then affixed to the sidewall 21, sealing the contents inside the bottle 2.

[0014] The piercing system 1 further comprises a piercing member 4, arranged within the neck 25 of the bottle 2, so that it is free to move both axially and rotationally. Orifices 41 provide a flow path to allow fluid to flow from the container 2, through the piercing member 4, once the frangible membrane 26 has been broken. A droplet nozzle 46 may be provided downstream of the piercing member 4, to enable the contents of the container to be dispensed in droplet form.

[0015] Finally, the piercing system 1 includes a closure cap 5 having a sidewall 51 with complimentary screw threads 57 to those of the bottle neck defined thereon. A conventional tamper-evidence band 52 is frangibly connected to the free edge of the skirt 51.

[0016] The closure cap 5 and piercing member 4 are both provided with complimentary cam surfaces 55, 45 which are arranged to interact when the closure cap 5 is unscrewed from the container 2, to drive the piercing member 4 towards and through the frangible membrane 26. Hence, on first opening of the closure cap 5, the piercing member 4 is driven axially through the frangible membrane 26 and remains lodged therein (as shown in Fig.2). The contents of the container 2 may thereafter be dispensed through the orifices 41 defined in the piercing member 4 and the nozzle 46. The closure cap 5 may thereafter be replaced on the container neck 25 to protect the opened bottle 2 from contamination and/or spills. Fig.2 shows the piercing system 1 after activation of the piercing member 4, with the closure cap 5 replaced on the bottle neck 25.

[0017] Figs. 3 and 4, show horizontal sections through the piercing system according to the invention showing the piercing member and ratchet arrangement in more detail. The piercing member 4 comprises three ribs 41 radiating from a central connection point. When the membrane on the container is pierced, the fluid contents of the container flows between the ribs 41 and out through the orifices 41 in the piercing member 4. Ratchets 6, 7 are provided on the attachment portion 3 and the piercing member 4 respectively.

[0018] Figs. 5 and 6, show an enlarged, simplified view of the ratchet arrangement shown in Figs. 3 and 4. When the piercing member 4 / closure cap 5 is first applied to the bottle 2, it is screwed on in a clockwise direction (as indicated in Fig.5) and the ratchet 7 on the piercing member slides past the ratchet 6 on the attachment portion 3 of the bottle neck. Thus, the piercing member 4 is free to rotate with the closure cap 5 and the piercing member does not move axially.

[0019] On first opening of the closure cap 5, a user unscrews the closure cap 5 in an anti-clockwise direction (as indicated in Fig.6). The ratchets 6, 7 engage and the piercing member 4 is thereby prevented from rotating with the closure cap 5. Because the piercing member can no longer rotate, the remaining unscrewing motion of the closure cap 5 is converted (by the cam arrangement) to move the piercing member 4 axially and drive it through the frangible membrane 26 on the bottle 2.

[0020] Although in the embodiment described, the attachment portion is provided as part of the neck of the bottle, it is readily apparent that the attachment portion may equally be provided by the body of a closure, attached to the container neck. Furthermore, it will be apparent that the piercing system according to the invention may be applied to closure systems for other applications, such as carton or tube closures for example.

Claims

1. A piercing system for a package sealed by a frangible membrane, the piercing system comprising
an attachment portion having a screw thread defined thereon,
a closure cap, having a complimentary screw thread, to allow the closure cap and attachment portion to be releasably connected together, and
a piercing member, arranged to move axially within the attachment portion,
the closure cap and piercing member having complimentary cam members, adapted to drive the piercing member towards the membrane when the closure cap is first unscrewed from the attachment portion, characterised in that
the attachment portion and piercing member further comprise complimentary ratchets, adapted to slip relative to one another when the closure cap is screwed on to the attachment portion, thereby allowing the piercing member to rotate relative to the attachment portion, but to engage when the closure cap is first unscrewed from the attachment portion, thereby preventing rotation of the piercing member and engaging the cam members to convert the rotational movement of the closure cap into axial movement of the piercing member.

2. A piercing system according to claim 1, wherein the ratchet on at least one of the attachment portion and the piercing member comprises a plurality of teeth, each tooth having a shallow sloping face and a steep engagement face,
the ratchet teeth orientated such that on screwing the closure cap onto the attachment portion, the ratchets slide relative to one another across the shallow sloping face, but on unscrewing of the closure cap the ratchets engage against the steep engagement face, preventing rotation of the piercing member.

3. A piercing system according to claim 2, wherein the ratchets on both the attachment portion and the piercing member have ratchet teeth.

4. A piercing system according to claim 3, wherein the ratchet on the attachment portion comprises a plurality of ratchet teeth and the ratchet on the piercing member comprises 2 ratchet teeth equi-spaced and disposed at 180º to one another.

5. A closure / container combination comprising a container having a frangible membrane and a piercing system according to any one of the preceding claims, wherein the container defines the attachment portion of the piercing system and the closure cap and piercing member are attached thereto.

6. A closure / container combination according to claim 5, wherein the frangible membrane has a zone of weakening defined by lines of localised thinning in the shape of a multi-pointed star and the piercing member comprises a plurality of axially extending ribs, the number of ribs being fewer than the number of lines of localised thinning.

7. A closure / container combination according to claim 6, wherein the zone of weakening in the membrane comprises 4 lines of localised thinning arranged in the form of a cruciform and the piercing member has 3 axially extending, equispaced ribs.

8. A closure / container combination according to any one of claims 5 to 7, wherein the piercing member includes at least one orifice to define a flow path through the piercing member.

9. A closure / container combination according to any one of claims 5 to 8, wherein the piercing system further includes a nozzle through which the contents of the container may be dispensed in droplet form.

Drawing