GB1560583A

GB1560583A - Childproof screw closure for the openings of receptacles and a method of producing such screw closures

Info

Publication number: GB1560583A
Application number: GB45215/76A
Authority: GB
Original assignee: Individual
Current assignee: Individual
Priority date: 1975-10-29
Filing date: 1976-10-29
Publication date: 1980-02-06
Also published as: FR2329533B3; NL7611997A; FR2329533A1; SE7611849L; CH598071A5

Description

(54) CHILDPROOF SCREW CLOSURE FOR THE OPENINGS OF RECEPTACLES, AND A METHOD OF PRODUCING SUCH SCREW CLOSURES (71) I, GAUNTER KRAUTKRAMER, a citizen of the Federal Republic of Germany, of 2 Friedrichstrasse, 6501 Budenheim, German Federal Republic, do hereby declare the invention for which I pray that a patent may be granted to me, and the method by which it is to be performed, to be particularly described in and by the following statement: This invention relates to a screw closure for the opening of a container such as a bottle, canister, tube or the like, the closure having a safety feature making it difficult to unscrew the closure and therefore to open the container, and to a method of producing such screw closures.

Screw closures having such safety features are used in connection with the packing of possibly harmful or toxic articles, especially medicines, and are often called 'iChildproof screw closures".

Most of such closures are so devised that the operation of opening the screw closure i.e., of unscrewing the same - requires the combination of two movements. It has been found by experience that small children cannot carry out this combination of movements.

Previously proposed "childproof" screw closures are usually two-part devices, often in the form of two caps which are pushed one over another, the outer cap being adapted to be deformed inwardly by lateral pressure so as to be engaged positively, by way of ribs on its inside, with the actual screw cap. Only once the lateral pressure has been applied can the cap be unscrewed from the container it closes.

These two-cap closure devices have to be manufactured in two separate moulding steps and then assembled, so that the production costs of the complete closure are considerable.

According to one aspect of the present invention there is provided a childproof screw closure for a container, wherein the closure comprises an internally threaded screw cap for closing a threaded opening of the container and having external fluting and a ring surrounding the screw cap so as to be readily rotatable relative thereto but locked thereto in the axial direction, said ring having on two diametrically opposite sides zones departing from the otherwise circular radial cross-section of the ring being formed with internal teeth. the arrangement being such that radial pressure on said zones of the ring causes the internal teeth thereof to engage the external fluting on the cap, thereby locking the ring and cap so that they can be turned as one. The external fluting can be provided either over the entire periphery of the cap or merely over some of such periphery.

According to another aspect of the present invention there is provided a childproof screw closure for a container, wherein the closure comprises an internally threaded screw cap for closing a threaded opening of the container and having external fluting and a ring for surrounding the screw cap so as to be rotatable relative thereto, said ring having on two diametrically opposed sides zones departing from the otherwise circular radial cross-section of the ring and formed internally with teeth, and wherein the screw cap and ring are integral with one another along a thin readily separable region extending in the radial direction from one end of the ring to what will, in use, be the other end of the cap, whereby upon breaking said region by axially moving the cap and ring relative to each other, the cap can be introduced into the ring and locked thereto in the axial direction to provide a closure in which radial pressure on said zones of the ring causes the internal teeth thereof to engage the external fluting on the cap, thereby locking the ring and cap so that they can be turned as one.

So that the cap parts which project above the ring cannot be gripped by the teeth of a child, one end, i.e. the top surface, of the cap is preferably smooth and has at its edge a flange which rests on the corresponding edge of the ring.

The screw cap may have on its outer wall a corrugation which, upon introduction of the cap into the ring, engages in a groove in the inside wall of the ring, thereby to lock the cap and ring in the axial direction.

It has often been found that the user must pay particular attention to closing the container - i.e., to screwing up the cap - so that the container often fails to be closed properly. Such manipulations also cause difficulties in manufacturing the closure.

In order to obviate this disadvantage, the inside wall of the ring may be formed with additional saw-teeth which extend in the direction of screwing-up; and the cap outside wall has two oppositely located catch elements for engaging the saw-teeth. Consequently. when the screw closure including the ring is screwed up, pressure need not be applied to the ring since the same always remains coupled with the screw cap during screwing-up. The two opposite catch elements are rugged and may be of saw-tooth construction.

Raised centering parts are preferably disposed between the catch elements on the outside of the screw cap.

In a screw closure having on the outside wall of the screw cap a corrugation which, upon introduction of the cap into the ring, engages in a groove in the inside wall of the ring, additional saw-teeth of the ring and the catch elements of the screw cap are, conveniently, disposed above the corrugation, i.e.

to that side of the corrugation remote from that part of the closure intended to engage the container. Consequently, the ring and the screw cap always remain connected to one another during screwing-up, but in unscrewing - i.e.. opening - pressure must be applied to the outside wall of the ring at two places to couple the ring and the screw cap together.

As the ring has on two opposite sides zones departing from the otherwise circular radial cross-section of the ring, and as the internal teeth on the ring are formed at places where zones are disposed, the places where radial pressure must be applied to the ring during unscrewing are clearly apparent.

Also, the zones considerably increase the distance between the fluting on the outside of the cap and the internal teeth of the ring, thus obviating the risk of accidental and unwanted operation of the screw cap.

The force required to engage the engageable elements with one another can be predetermined by the shape and wall thickness of the zones. Consequently. such force can be increased to such an extent that no child of the age group of interest can operate the screw cap accidentally.

According to yet another aspect of the present invention there is provided a method of producing a screw closure of the kind described, wherein the screw cap and ring are extrusion moulded so as to be integral with one another along a thin readily separable region extending in the radial direction from one end of the ring to what will eventually be the other end of the screw cap, and wherein the resulting extrusion is broken into two parts at said region by axially moving the cap and ring relative to each other to enable the cap to be introduced into the ring.

In order to enable the invention to be more readily understood, reference will now be made to the accompanying drawings, which illustrate diagrammatically and by way of example an embodiment thereof, and in which: Figure 1 is a sectional view of a childproof screw closure for a container, the left-hand side of the drawing showing two parts of the closure before the closure has been assembled and the right-hand side of the drawing showing the closure after it has been assembled: Figure 2 is a section on the line IX-IX of Figure 1 of the assembld closure, and Figure 3 is a section on the line X-X of Figure 1 of the assembled closure.

Referring to Figures 1 to 3 of the drawings, there is shown a childproof screw closure comprising a screw cap 1 formed externally with fluting 2 and internally with screw threading, and ring 3 formed internally with a toothed region 4.

The screw cap 1 and the ring 3 are, as shown in the left-hand side of Figure 1, extrusion moulded so as to be integral with one another along a thin readily separable region extending in the radial direction from one end of the ring to what will eventually be the other end of the screw cap. The resulting extrusion is then broken into two parts at the readily separable region by axially moving the cap and ring relative to each other so that the screw cap can be introduced into the ring as shown in the right-hand side of Figure 1, whereafter the screw cap can be screwed onto a container to close it.

The cap 1 also has a corrugation 5 which, after introduction of the cap into the ring, engages in a groove 7 in the inner wall of the ring. At its top edge, the cap 1 has an annular flange 6 which, after introduction of the cap into the ring, rests on the top edge of the ring.

The cap 1 is introduced into the ring 3 and the fit is such that the ring can be rotated readily relative to the cap. In order to be able to un-screw the cap from, e.g. the neck of a bottle, a considerable lateral pressure must be applied to the side wall of the rin, for only when this is done will the toothed region 4 of the ring engage with the fluting on the cap, thereby locking the ring and cap so that they can be turned as one.

As more clearly shown in Figures 2 and 3, the screw cap 1 of the childproof screw closure has external saw-toothed fluting 2, and the ring 3 has internal saw-toothed regions 4. In addition, saw-toothing 12 is formed on the inside wall of the ring above the corrugation 5. The outside wall of the cap at two opposite places catch elements 13 and 14 for engaging with the saw-toothing engages the catch elements 13 and 14 when the cap is screwed up but rides over the catch elements when the cap is screwed in the other direction as if to open it.

Between the catch elements 13 and 14 the cap 1 has on its outside raised parts 15 and 16 which help to centre the cap in the ring.

At two opposite locations, the ring has zones 17 and 18 which depart from the otherwise circular radial cross-section of the ring.

The first-mentioned inner toothed regions 4 of the ring are provided at the places where the zones 17 and 18 are disposed so that by pressing in at these zones the tooth regions 4 engage the fluting 2 thereby enabling the closure to be unscrewed from e.g., the neck of a bottle, by turning the cap and ring together.

WHAT I CLAIM IS: 1. A childproof screw closure for a container, wherein the closure comprises an internally threaded screw cap for closing a threaded opening of the container an having external fluting and a ring surrounding the screw cap so as to be readily rotatable relative thereto but locked thereto in the axial direction, said ring having on two diametrically opposite sides zones departing from the otherwise circular radial crosssection of the ring and being formed with internal teeth, the arrangement being such that radial pressure on said zones of the ring causes the internal teeth thereof to engage the external fluting on the cap, thereby locking the ring and cap so that they can be turned as one.

2. A childproof screw closure for a container, wherein the closure comprises an internally threaded screw cap for closing a threaded opening of the container and having external fluting and a ring for surrounding the screw cap so as to be rotatable relative thereto, said ring having on two diametrically opposed sides zones departing from otherwise circular radial cross-section of the ring and formed internally with teeth, and wherein the screw cap and ring are integral with one another along a thin readily separable region extending in the radial direction from one end of the ring to what will, in use, be the other end of the cap, whereby, upon breaking said region by axially moving the cap and ring relative to each other, the cap can be introduced into the ring and locked thereto in the axial direction to provide a closure in which radial pressure on said zones of the ring causes the internal teeth thereof to engage the external fluting on the cap, thereby locking the ring and cap so that they can be turned as one.

3. A screw closure as claimed in Claim 1 or 2 wherein one end surface of the cap is smooth and has at its edge a flange which rests or is intended to rest on the corresponding edge of the ring.

4. A screw closure as claimed in any one of Claims 1 to 3, wherein the outer wall of the cap has a corrugation which engages or is intended to engage in a groove in the inside wall of the ring thereby to lock the cap and ring in the axial direction.

5. A screw closure as claimed in any one of Claims 1 to 4, wherein the inside wall of the ring is formed with additional saw-teeth which extend in the direction of screwing-up and the outside wall of the cap has two oppositely located catch elements for engaging the saw-teeth.

6. A screw closure as claimed in Claim 5, wherein the screw cap has on its outside wall a corrugation which, upon introduction of the cap into the ring, engages in a groove in the inside wall of the ring, and wherein the additional saw-teeth of the ring and the catch elements of the screw cap are disposed to that side of the corrugation remote from the part of the closure intended to engage the container.

7. A screw closure as claimed in Claims 5 and 6. wherein the outside of the screw cap has raised centering parts between the said catch elements.

8. A screw closure as claimed in any one of Claims 1 to 7 wherein the closure is made of plastics.

9. A childproof screw closure for a container substantially as hereinbefoe described with reference to Figures 1 to 3 of the accompanying Drawings.

10. A method of producing a screw closure as claimed in any one of the Claims 1 to 9, wherein the screw and ring are extrusion moulded so as to be integral with one another along a thin readily separable region extending in the radial direction from one end of the ring to what will eventually be the other end of the screw cap, and wherein the resulting extrusion is broken into two parts at said region by axially moving the cap and ring relative to each other to enable the cap to be introduced into the ring.

**WARNING** end of DESC field may overlap start of CLMS **.

Claims

**WARNING** start of CLMS field may overlap end of DESC **. able to un-screw the cap from, e.g. the neck of a bottle, a considerable lateral pressure must be applied to the side wall of the rin, for only when this is done will the toothed region 4 of the ring engage with the fluting on the cap, thereby locking the ring and cap so that they can be turned as one. As more clearly shown in Figures 2 and 3, the screw cap 1 of the childproof screw closure has external saw-toothed fluting 2, and the ring 3 has internal saw-toothed regions 4. In addition, saw-toothing 12 is formed on the inside wall of the ring above the corrugation 5. The outside wall of the cap at two opposite places catch elements 13 and 14 for engaging with the saw-toothing engages the catch elements 13 and 14 when the cap is screwed up but rides over the catch elements when the cap is screwed in the other direction as if to open it. Between the catch elements 13 and 14 the cap 1 has on its outside raised parts 15 and 16 which help to centre the cap in the ring. At two opposite locations, the ring has zones 17 and 18 which depart from the otherwise circular radial cross-section of the ring. The first-mentioned inner toothed regions 4 of the ring are provided at the places where the zones 17 and 18 are disposed so that by pressing in at these zones the tooth regions 4 engage the fluting 2 thereby enabling the closure to be unscrewed from e.g., the neck of a bottle, by turning the cap and ring together. WHAT I CLAIM IS:

1. A childproof screw closure for a container, wherein the closure comprises an internally threaded screw cap for closing a threaded opening of the container an having external fluting and a ring surrounding the screw cap so as to be readily rotatable relative thereto but locked thereto in the axial direction, said ring having on two diametrically opposite sides zones departing from the otherwise circular radial crosssection of the ring and being formed with internal teeth, the arrangement being such that radial pressure on said zones of the ring causes the internal teeth thereof to engage the external fluting on the cap, thereby locking the ring and cap so that they can be turned as one.