The present invention relates to a safety screw cap for bottleneck type containers associated with a dispensing device, and an arrangement of botde, dispenser and cap.

The administration of liquid medicines from a bottle can be effected easily, cleanly and quantitatively by means of dispensing devices such as pipettes, droppers, syringes and similar devices. In order to prevent the loss or soiling of the dispensing device, it is advantageously left in the neck of the container when not in use. This arrangement, however, needs to be safeguarded in such a way that it cannot be opened, especially not by children, and the contents of the container be abused. This problem is not just limited to medicines, but may also occur with household and industrial liquids in bottles and similar containers. Moreover, it is expected that in the very near future most regulatory authorities will oblige manufacturers of liquid medicines to present their drug in child- resistant containers, in order to obtain marketing approval for such presentations. Consequently, there is a need for a device that renders child-resistant an arrangement of a botde with a dispenser removably fitted therein.

The most effective child-resistant closures for botdes today are safety screw caps that require a combination of two movements to open, generally an axial force on the cap in the direction of the container and simultaneously an unscrewing movement. Such caps are known from GB-2,182,648 and GB-2,187,177.

The object of the invention is to provide a safety screw cap especially designed for use on a botdeneck container associated with a dispensing device, i.e. a cap that can be screwed over the dispensing device left in the neck of the botde when not in use and that renders the whole arrangement child-resistant. At the same time said cap should retain the advantages of known safety screw caps such as ease of manufacture and assembly (especially by automatic machinery) and low production cost.

The problem is solved by a safety screw cap suitable for bottleneck type containers associated with a dispensing device removably fitting within and on the rim of said bottleneck, comprising a first cylindrical element constituting the cap proper, and a second cylindrical element fitted coaxially over the first element, whereby the outer surface of the first element and the inner surface of the second element are equiped with means that cause the first element to rotate as one with the second element when the

second element is screwed onto the neck of the container, and that prevent removal of the cap by unscrewing unless an axial force in the direction of the container is exerted on the second element, thus causing positive contact between both elements, characterized in that the first cylindrical element includes an upper portion having a smaller diameter than the lower portion, thus causing an external flange extending radially from the dispensing device to be tighdy fitted on the rim of the botdeneck when the cap is screwed completely onto the bottleneck, and said upper portion has a depth (or length) that is just sufficient to accommodate the pan of the dispensing device extending upwards from the flange.

Further features and modifications as well as the advantages of the new cap according to the invention will be described hereinafter in more detail, by way of example, with reference to the accompanying drawings where :

Figure 1 shows a sectional view of a safety screw cap according to the invention mounted on a botdeneck associated with a pipette as a dispenser; and Figure 2 shows a a horizontal section through II-II in Figure 1.

The screw cap shown in the drawings comprises a first cylindrical element (1) that constitutes the cap proper, and serves to close the container. The cap is conveniently made of a relatively rigid moulded plastic such as polyethylene or polypropylene, and is provided with an internal thread that pairs with an external thread offered by the neck of a standard type of container. The container, if intended for holding and dispensing liquid medicines, preferably is a bottle which is made out of glass or an acceptable rigid plastic such as polyethylene or polypropylene, and typically may have a capacity of 0.1 1.

In general, the outer surface of the first element and the inner surface of the second element are equiped with ratchet teeth, projections and recesses and the like means that cause the elements to rotate as one when the cap is screwed onto the neck of the container, and that prevent removal of the cap by unscrewing. Suitable arrangements of this type are described in, for example, GB-2,182,648 and GB-2,187,177, and the latter arrangement will be used by way of specific example throughout the further description and drawings.

The first cylindrical element 1 includes an upper portion 4 having a smaller diameter than the lower portion 5, thus causing an external flange 14 extending radially from the dispensing device 13 to be tightly fitted on the rim of the bottleneck 3 when the cap is screwed completely onto the botdeneck, and said upper portion 4 has a depth (or length)

that is just sufficient to accommodate the part of the dispensing device 13 extending upwards from the flange 14. In order to be effective, the diameter of the upper part 4 should be smaller than that of the lower part only just, thus forming a shoulder in the first element 1. It should be noted that the depth or length of the upper portion 4 having a smalller diameter man the lower portion 5, preferably is such that it will accommodate only a fully inserted dispenser 13. In case said dispenser is no fully inserted, the act of screwing on the safety screw cap will cause the dispenser to be driven fully into the bottle.

Suitable dispensers for use with the safety screw cap of the present invention are pipettes, droppers or syringes having an annular flange 14 jutting radially outwards with a diameter equal to that of the botdeneck outside. Said dispensers typically have a height and inside diameter such that their chamber volume equals desired liquid medicine doses, typically ranging up to 5 ml. Droppers and syringes preferably will have a graduated cylinder ; pipettes preferably will have a graduated plunger which is calibrated, usually in units of volume, the zero line (empty dispenser) being aligned with the top of the annular flange (14) when the plunger is inserted completely in the barrel.

The outer cylindrical wall of the first element 1 exhibits a plurality of first teeth 6 that coincide with relative straightline cylindrical generators; one flank of each such tooth 6 is merged into the cylindrical profile of the wall . The top most surface of the first element 1 exhibits a plurality of first radial dogs 8 arranged in circular pattern, and a frusto-conical projection 9 located within the circle of dogs 8 and disposed coaxially with the element 1 itself.

The screw cap comprises a second cylindrical element 2, similarly embodied in moulded plastic, which fits over and encapsulates the first cylindrical element, the two elements being coaxially disposed following assembly. The inwardfacing cylindrical wall of the second element 2 exhibits a plurality of second teeth 7 coinciding with relative straighdine cylindrical generators; one flank of each tooth 7 is merged into the cylindrical profile of the wall. These second teeth 7 are designed to engage the first teeth 6 offered by the first element 1.

The two sets of teeth 6 and 7 are arranged in such a way as to create a catch mechanism, embodied such that their dissimilar flanks will allow relative anticlockwise rotation of the two elements 2 and 1, but inhibit relative clockwise rotation. In short, the effect of the two sets of teeth 6 and 7 is to permit of screwing the cap onto the neck of the container

(clockwise rotation), whilst preventing its removal by unscrewing (anticlockwise rotation); it will be observed, in fact, that the merged flanks of the teeth simply ride over one another when the second element 2 is rotated anticlockwise, such that the first element 1 remains stationary. It will be observed also that the thickness of the cylindrical wall of the second element 2 is reduced at the points where the teeth 7 are located, to the end of facilitating passage of the flanks of the second teeth 7 over those of the first teeth 6. The effect of this reduction in thickness is to enhance flexibility, hence deformability, of the cylindrical element 2, and thus favour passage of the one set of teeth over the other.

In the event of an attempt being made, for example, by a child, to open the container simply by turning the second cylindrical element 2, the parts of the second element 2 that have been reduced in thickness will snap back into shape once contact between the merged flanks of the teeth 6 and 7 has ceased, thereby causing the second teeth 7 to strike against the outer cylindrical surface of the first element 1 and produce audible warning of such an attempt.

The topmost internal surface of the second element 2 exhibits a plurality of second radial dogs 10; these are arranged in a circular pattern similar to that of the first dogs 8, and it will be seen from figurel that the two sets of dogs 8 and 10 occupy a common circular band. The same top internal surface also exhibits a flexible annular projection 11 that comes to rest on the aforesaid frusto-conical projection 9 when the second cylindrical element 2 is fitted over the first cylindrical element 1. The depth of the annular projection 11 is such that the first dogs 8 will normally remain clear of the second dogs 10 by a small margin, and no contact can occur between the two sets of dogs 10 and 8 when the second element 2 is rotated. Applying light axial force to the second element 2 in the direction of element 1, the annular projection 11 will flex and spread over the conical surface of the projecting frustum 9, and thus shorten the distance between the two surfaces from which the sets of dogs 10 and 8 project. Rotating the second element 2 with axial force thus applied, the second dogs 10 engage the first dogs 8 and cause the two elements to turn as one, thus enabling the cap 1 to be twisted off, and the container opened. Releasing downward pressure on the second element 2, the flexible annular projection 11 will spring back into shape and distance the second element 2 from the first 1 once again, thereby disallowing contact between the first and second dogs 8 and 10. Deformability of the flexible annular projection 11 is enhanced by inclusion of a plurality of slots 12 coinciding with respective axial generators. In short, the screw cap can be twisted onto the neck of the container simply rotating the second cylindrical element 2

clockwise, by virtue of the positive contact created between the teeth 6 and 7, whereas to unscrew the cap 1, axial force must be applied to the second element 2 in the direction of element 1, i.e. in the direction of the container, before turning anticlockwise, in order to ensure positive contact between the second dogs 10 and the first dogs 8.

The screw cap disclosed may further comprise a composite collar which incorporates a first ring 15 and a second ring 16. The first ring 15 is gripped inside and underneath the first cylindrical element 1 whereas the second ring 16, which is connected coaxially with the first ring 15 via perforations, constitutes a break-open or tear-off seal. At the moment when the screw cap is fitted to the neck of the container, the second ring 16 will lodge beneath a rim with which the neck of a conventional container is generally provided, and cannot thus be twisted off together with the cap 1 when unscrewed. Accordingly, the perforations that connect the first ring 15 and the second ring 16 will break apart when the cap is removed for the first time, and one is provided with clear evidence of the container's having been opened. The tear-off band should be removed only immediately prior to use and provides an easily discemable proof of non-tampering with the bottle. Removal of the tear-off band enables the cap to be unscrewed and the dispenser to be withdrawn from the bottle.

In order to facilitate assembly of the bottle, dispenser and safety screw cap during manufacture as well as during end-use, the bottle is conveniendy equipped with a means for arranging the dispensing device coaxially with the botde, e.g. a centralizing ring. Preferably, a stopper is employed having a central perforation which just accommodates the dispensing device, and having an annular flange with about the same diameter as flange 14. Consequently, the present invention also concerns a bottle for holding and dispensing liquid medicines which is equipped with a safety screw cap as described hereinbefore and a dispensing device 13, characterized in that it further comprises a central stopper 17, the lower part of which fits in the bottleneck, the upper pan 18 of which constitutes an annular flange jutting outwardly over the rim of the botdeneck, and which is centrally perforated in order to accommodate the dispensing device, and thus assures that the flange 18 of the stopper and the flange 14 of the dispensing device are aligned coaxially, and allows the safety screw cap to be screwed onto the bottleneck without effon.

Preferably the central stopper 17 is shaped in such a way that upon withdrawing the dispensing device 13 any liquid such as syrup sticking thereto is scrubbed off by the lower pan of the central stopper.

This arrangement at the same time prevents smudging of the topmost pan of the central stopper and the central perforation upon re-insertion of the dispensing device 13 into the botde. Such smudging could cause the dispensing device 13 to become stuck after some use. A further improvement to the central stopper consists of a tiny hole perforating the central stopper 17 axially. This tiny hole should allow air to flow out of or into the bottle upon withdrawing or re-inserting the dispensing device 13.

The dispensing device employed with said botde may be a pipette, a dropper or a syringe as described hereinbefore, in particular a pipette having a graduated plunger.

The botde according to the instant invention is easily assembled using standard machinery. By virtue of the present arrangement, the dispenser can be kept neady covered up and cannot be contaminated, nor for that matter can the medicine in the bottle. The bottle can be stored, sold and used as supplied by the manufacturer. Besides its being childproof, simple and hygienic, the bottle according to the present invention has the further advantage that the botde, cap and the dispenser can be manufactured in a range of different sizes each with different diameters and/or lengths.