EP0025966B1 - Childproof closure - Google Patents

Description

The invention relates to a child safety closure made of plastic, for containers with a neck and screw thread, in the form of a screw cap, with a locking ring overlapping a transfer ring on the container neck, by means of whose elastic deformation the closure can be unscrewed.

For the storage of highly effective and / or z. B. in overdose of toxic or harmful substances, especially medicinal products, it is required that opening the corresponding container is made impossible by children.

Children are to be understood in particular as small children who are not yet able to read the appropriate labels or warnings on the container. In addition to the child safety lock mentioned at the outset, a number of further locks are known, which are either difficult to manufacture, complex to assemble or difficult to use even by adults, for example older people or people weakened by illness.

A large number of child safety locks are already known, but they do not meet practical requirements. In a known child safety closure, a safety ring is provided with at least one locking lug arranged on the safety ring, which interacts with at least one triangular holding lug arranged on the neck of the container (DE-A-2 449 134). In this known child safety lock, the locking ring firmly connected to the screw cap must be deformed at certain points in order to open the lock in order to overcome the locking effect of a locking cam cooperating with a retaining cam. The opening process in this known closure therefore requires, on the one hand, precise knowledge of the closure in order to apply the considerable force required for sufficient deformation at the appropriate points.

Child safety locks are also known, in which two caps are coaxially inserted into one another and these two caps have latching cams and pawls on their top or inside. Since both parts are made of plastic, the locking lugs and pawls or similar entrainment and locking elements are deformed or worn to such an extent that the function is no longer guaranteed if they are operated frequently. This wear and deformation stems from the fact that with these closures the force for opening the closure has to be transmitted directly via the locking lugs, cams or the like.

In contrast, the invention is based on the object of designing a child safety lock of the type described at the outset in such a way that it is simple to produce, can be applied mechanically to associated containers, and the force required for opening can be set in a simple manner.

This object is achieved according to the invention in a child safety lock of the type mentioned essentially in that the locking ring has an approximately triangular inner locking step and at least one axially parallel slot that the locking ring is surrounded by an outer ring which with the locking ring on at least two oblique struts is connected and in the region of or an axially parallel slot of the locking ring has a deformable section which, in the event of radial pressure, by enlarging its radius of curvature via the oblique struts adjacent to the axially parallel slot, expands the locking ring while enlarging the axially parallel slot in such a way that the locking ring extends over the transfer ring on the container neck can slide and that cap, locking ring and outer ring and oblique struts are integrally formed.

The child safety lock according to the invention has considerable advantages over the known child safety locks. The one-piece design enables rapid production in injection molding machines without post-processing. Assembly times for related parts, such as those used in known child safety locks, are eliminated. The number of slots in the locking ring allows the strength of the locking ring or the pressure force required for screwing on or unscrewing the closure from the associated container to be set in a simple manner.

To adapt the pressure forces required for screwing on or unscrewing from the container, it is advantageous according to a development of the invention that several pairs of V-shaped oblique struts are provided between the locking ring and the outer ring.

In a preferred embodiment of the invention, at least one slot is provided in one step between the outer ring and the screw cap in the region of the deformable section. This facilitates the stretching of the deformable portion of the outer ring.

According to a modified embodiment, a reduction in wall thickness can be provided in one step in the deformable section, such that a relatively thin plastic skin is formed which is elastically deformable.

In an expedient embodiment of the invention, the outer ring has at least one outwardly directed pressure wart in its deformable section.

It is advantageous in terms of production technology if the printing nipple (s) is (are) hollow.

• Fig. 1 einen Querschnitt eines erfindungsgemäßen Kindersicherheitsverschlusses, gemäß der Linie I-I in Fig. 2,
• Fig. 2 eine Ansicht in Pfeilrichtung A der Fig. 1 und
• Fig. 3 eine Draufsicht auf einen Verschluß nach der Erfindung.

Further details and advantages of the invention are explained in more detail with reference to the drawing, which schematically represents an embodiment. It shows

• 1 shows a cross section of a child safety lock according to the invention, along the line II in FIG. 2,
• Fig. 2 is a view in the direction of arrow A of Fig. 1 and
• Fig. 3 is a plan view of a closure according to the invention.

The child safety closure according to the invention is, as shown in Fig. 1, in one piece and has a screw cap part 1 with internal thread 2 and gripping ribs 3. The internal thread 2 cooperates with the external thread on the neck of a (not shown) container. On the inner surface of the screw cap 1, sealing rings 20 and / or an attachment 19 for mounting and for sealing a container insert, such as pouring spout, dropper or the like, can be provided.

In the lower area, a locking ring 4 is provided, which has an approximately triangular locking step 5 on its lower edge. Due to the inclined inner edge of the locking step 5, when the closure 1 is screwed onto a container, the locking ring 4 is stretched so far when it hits the transfer ring that it can slide over the transfer ring. Due to the shorter flank of the triangular locking step 5, screwing back and thus unintentional or unauthorized opening of the closure for a child is avoided with certainty.

In order to enable the closure to be opened by an adult, an outer ring 7 is formed on a step 8 according to the invention, so that there is an annular gap between the inner ring 4 and the outer ring 7. The locking ring 4 has at least one axially parallel slot 6, as can be seen in FIG. 2, by means of which the corresponding expansion of the locking ring 4 when reaching over the transfer ring is made possible both when screwing on and when unscrewing.

The outer ring 7 is connected to the locking ring 4 via at least two oblique struts 9, 10 which are arranged on both sides of the axially parallel slot 6. In the area of these axially parallel slots 6, the outer ring 7 has a deformable section 11.

From Fig. 2 it can be seen that in the region of the deformable portion 11 of the outer ring 7 pressure warts 17 and 18 can be provided, which are advantageously hollow, i. H. have essentially the same wall thickness as the other regions of the outer ring 7.

To set the compressive force required to open the closure, further oblique struts can be arranged in the annular gap between the locking ring 4 and the outer ring 7. In Fig. 2 four pairs of V-shaped oblique struts 12, 13, 14, 15 are shown. In Fig. 1 it can be seen particularly clearly that the outer ring 7 in the region of its deformable portion 11 in the step 8 has a slot 16 to facilitate the deformation. Instead of the slot 16, however, a reduction in wall thickness can also be provided, such that there is a thin plastic skin at this point, which is relatively easily deformable.

3, which shows a top view, the arrangement of the slot 16, the pressure nipples 17, 18 and oblique struts 9 and 10 can be clearly seen.

When a child safety lock according to the invention is screwed on, no special measure is required, since the screw cap 1 is screwed on in a known manner by screwing the internal thread 2 onto the external thread of the container neck. As soon as the locking ring 4 with its triangular locking step 5 abuts the transfer ring on the container neck, only a greater torque is required in order to bring about an expansion of the locking ring 4 by means of the axially parallel slot 6 and an overlap of the locking ring 4 via the transfer ring. The strength of the force required for this is determined by the oblique struts 9, 10 or 12 to 15 acting in the manner of a collet. Another way of influencing the screwing force is to choose the hardness of the plastic used for the closure.

If a child tries to unscrew the cap from the container again, this will not succeed because the shorter leg of the triangular locking step 5 lies against the transfer ring from below and prevents unscrewing even with a relatively large amount of force being applied to the cap.

Opening is only possible when inward radial pressure forces are exerted in the region of the deformable section 11 of the outer ring 7. As a result, the deformable section 11 deforms from its approximately circular section shape into an elongated shape which is approximately tangential to the locking ring 4 and thereby pulls the inner locking ring 4 apart by enlarging the oblique struts 9, 10, enlarging the axially parallel slot 6 to such an extent that the locking ring 4 over the transfer ring can slide on the neck of the container.

If the pressure warts 17, 18 shown in FIG. 1 are missing in the simple embodiment, then even an older child cannot see that the closure can be opened by exerting a radial pressure. Even if a child tried to open it by deforming the outer ring 7, it would have to catch the deformable portion 11 more or less by chance and continue to apply relatively strong radial compressive forces to unscrew the closure from the container while rotating.

To make it easier for adults to operate the child safety lock, a corresponding note can be attached to the surface of the screw cap 1 that the bead or the pressure nipple 17, 18 must be pressed inwards in order to open it.

Claims (6)

1. Child-proof safety lock made of plastics material, for containers having a neck and a screw thread in the form of a screw cap (1), and a locking or stop ring (4) which covers a transfer ring on the container neck and the elastic deformation of which can cause the lock to be unscrewed, characterised in that the locking ring (4) has an inner locking step or shoulder (5), which is apporximately triangular in cross-section, and at least one axially parallel slot (6), that the locking ring (4) is surrounded by an outer ring (7) which is connected to the locking ring (4) via at least two diagonal braces (9, 10) and, in the area of the or an axially parallel slot (6) of the locking ring (4), has a deformable section (11) which, when subjected to radial pressure as a result of an increase in its radius of curvature via the diagonal braces (9, 10) adjacent to the axially parallel slot (6), causes the locking ring (4) to expand during enlargement of the axially parallel slot (6) in such a manner that the locking ring (4) can slide over the transfer ring on the container neck, and that the cap (1), locking ring (4), outer ring (7) and diagonal braces (9, 10) are designed in one piece.

2. Child-proof safety lock according to Claim 1, characterised in that several pairs of diagonal braces (12-15) in a V-shaped arrangement are provided between the locking ring (4) and the outer ring (7).

3. Child-proof safety lock according to Claim 1 or 2, characterised in that, between the outer ring (7) and the screw cap (1), at least one slot (16) is provided in a step or shoulder (8) in the area of the deformable section (11) of the outer ring (7).

4. Child-proof safety lock according to Claim 1 or 2, characterised in that an elastically deformable plastic membrane or film, which is thinner than the remaining edge area of a step (8), is provided between the outer ring (4) and screw cap (1), in the area of the deformable section (11) of the outer ring (7).

5. Child-proof safety lock according to any one of Claims 1 to 4, characterised in that the outer ring (4) has, in its deformable section (11), at least one outwardly directed pressure bead (17, 18).

6. Child-proof safety lock according to Claim 5, characterised in that the pressure bead (beads) (17,18) is (are) hollow in design.

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