Child-proof container closure

p0001The present invention relates to a container closure with a provided on a container screw neck and a subsequent screwable screw cap, at least the threaded neck is composed of a deformable by finger pressure plastics material and wherein toothed elements are provided in the region of the screw neck and the screw cap, which, when fully screwed on the screw cap together in are engaged, and only then allow unscrewing the screw cap when either the threaded neck and / or the screw cap are deformed in the region of the tooth elements to bring the tooth elements out of engagement.

p0002Such a container closure is generally known as "closure with child safety." For further details and general characteristics of such container closures, reference 44 00 993.3 made to copending same assignee German Patent Application P, whose content is incorporated by reference into the present application. Here also, the present invention of the closure illustrated in this earlier application is applicable, but not exclusively limited. As described in this prior application, either the caps or the threaded connection can be deformed when the container closures in question to bring the toothed elements of the screw cap and screw neck of a closure lower part disengaged. Since the screw cap is internally threaded and the threaded connecting piece has an external thread, and consequently the toothed elements are located on the inside of the screw cap and on the outside of the threaded connection, has to be pressed with its gear teeth radially inwardly in the region of the toothing, either the threaded connection piece or the screw cap must be moved with their toothed regions radially outward, which is generally done by so-called "ovalization" by, for example, the screw cap is compressed on two opposite, offset relative to the interlocking elements 90 ° apart points. However, the application of the present invention is mainly, though not exclusively directed to a variant in which the threaded connecting piece of the container closure deformed, ie the toothed elements are pressed radially inwardly, while the screw cap consists of a harder as compared with the threaded connection piece of the container closure material which can be deformed less easily.

p0003The preferred material for the threaded connection having lower closure parts is polyethylene. This is especially true for so-called Balgverschlüsse, is in which the threaded connector connected via a bellows with a so-called sealing foot, which is in turn fixed in a container opening. Such Balgverschlüsse must be made of a relatively flexible, easily deformable material, so that the bellows on and can be everted. But also for the compression of the threaded connection itself, to bring the tooth elements to threaded neck and the screw cap is disengaged, it is necessary that the threaded socket consists of a sufficiently easily compressible, deformable and flexible material. At the same time, the material must of course be sufficiently resistant to the various container contents and must also withstand the mechanical stresses which occur without damage such as cracks or the like occur. All these features are very well filled with polyethylene, which does not exclude that other materials with similar properties to the closure portion or the threaded connection could be used.

p0004A disadvantage of the relatively easy deformability of a material such as polyethylene, however, is that the elasticity of the material is not always sufficient to fully restore the original shape after deformation. In other words, the threaded connection piece is compressed in the radial direction at two opposite points, and then released, so remains a portion of this deformation even after the re-releasing of the threaded connector yet. This results in the subsequent screwing of the screw cap, the engagement of the toothed elements of the screw cap and screw neck is shallower than in the original state. After repeated deformation and after a certain wear of the teeth through frequent opening and screwing the closure this may result in that the toothed elements not or only very slightly engage with each other, so that the shutter without compressing the screw neck without too much force by unscrewing the screw cap can be opened.

p0005The present invention is therefore based on the object to provide a container closure, in which fixed the problem of the lack of reliability after prolonged use of the closure, but at least mitigated.

p0006This object is achieved in that the threaded connector has a radially outward projection in a circumferentially to the interlocking elements offset portion.

p0007Since this projection is offset in circumferential direction relative to the interlocking elements, preferably by about 90 °, it has during the radial Einwärtsdrücken the toothed elements, the tendency to move in a radially outward direction. This so-called ovalization has further been already mentioned in connection with the screw cap top.

p0008Due to the limited elasticity of the material is, however, assumed at the screw neck from the fact that such deformation after release of the threaded connection will not be completely reversed, ie the threaded connector retains a shape in which areas with the interlocking elements radially inwardly and the areas are pressed with one or several radial protrusions outwardly. Screwed to such a threaded socket screw cap, however, ideally, a circular shape and is simultaneously a significantly harder, less easily deformable material, which moreover also has better elastic restoring forces. If such a screw cap screwed onto the still slightly deformed threaded connection, so enter at least towards the end of Verschraubungsvorganges not only the toothed elements of the screw cap and threaded connector engaged with each other, but also the 90 ° to the interlocking elements offset projection with a corresponding portion of the inner surface of the screw cap , This means that the result of the deformation additionally pressed outward radial projection is pushed back from the inner wall of the screw cap again radially inwardly, that is, the first remaining deformation of the threaded connection is made in this way actively by the screw cap again reversed so that the threaded connection piece essentially assumes the ideal circular shape. In this case also the areas of the screw neck with the toothed elements move simultaneously radially outwardly and thus improving the engagement with the interlocking elements of the closure cap. The projection may be formed in the manner of a radially outwardly protruding cams, and preferably has, of course, such dimensions that its outermost surfaces or points, which engage with the inner surface of the screw, have the same radial distance from the imaginary axis of the screw as the inner surface of the screw itself. Thus, the cam or the corresponding region of the threaded connection when screwing the screw cap is pushed back again exactly in the position corresponding to the exact, circular shape of the threaded connector. The exact shape of the cam or protrusion is of secondary importance. The cam and / or the lower edge of the screw cap can, for. Example, have inclined run-up surfaces, to facilitate the engaging of cams and contact inner surface of the screw cap. Alternatively, two diametrically opposed cams or projections are provided that are arranged in a staggered by 90 ° position to also diametrically opposed interlocking elements on the threaded connector.

p0009The axial position of the cam is of course selected such that it at least partially is completely screwed onto the threaded stub screw inside thereof and enters into engagement with the inner surface of the screw cap but still axially remains outside of the thread of the screw, because otherwise the screwing of could hamper cap. However, it would also be possible that the projection, analogous to the toothing of the screw cap in the above already mentioned DE-44 00 993.3, along an imaginary continuation of the thread, in this case of the threaded connection could be arranged.

p0010but preferably extends the projection or cam only in an area axially outside the thread of the screw cap (when fully screwed on), in contrast to the interlocking elements, which according to the preferred variant and in accordance with the referenced German Patent Application to in the threaded portion of the screw cap, whose toothed elements are arranged in continuation of a thread.

p0011In addition, an embodiment of the invention is preferred, wherein the edge of the screw cap in the area of ​​its toothed elements set back axially, or has a recess. With screwed cap such recess provides a view of the toothed elements of the screw neck freely and simultaneously defines the position for the placement of the finger on the threaded connector to compress this. The recess on the closure cap has at the same time the advantage that a larger area of ​​the threaded connection and above all a closer lying on the toothed elements of the screw neck portion can be detected by the fingers. This is especially important because in principle of about 90 ° to the toothed elements offset projection or cam in the tendency to compress the toothed areas hampered because he an ovalization of the threaded connection resists by bearing against the inner surface of the screw cap. However, the threaded connection between the cam and gearing elements has enough room for an escape radially outward. Because of these advantages, this recess would be useful also in the case of other fasteners without the above-mentioned protrusion, said recess should preferably extend up close to the Schraubkappenverzahnung.

p0012As an alternative to the projection on the screw neck a inwardly projecting origin could also be provided at a corresponding position on the inside of the screw cap, which, is arranged similar to the teeth elements in continuation of a thread.

p0013Further advantages, features and possible applications of the present invention will become apparent from the following description of a preferred embodiment and the associated figures. Show it:<dl id="dl0001" compact="compact"><dt>figure 1</dt><dd>an axial section through a closure according to the invention,</dd><dt>figure 2</dt><dd>a section perpendicular to the axis of the closure according to the line AA in Fig. 1,</dd><dt>figure 3</dt><dd>a variant of the closure according to the invention with a projection inside the screw cap, and</dd><dt>figure 4</dt><dd>a variant of the screw cap having a peripheral recess.</dd></dl>

p0014In Figure 1 shows a closely hatched closure portion 6, which has a so-called closure foot 7 which is einprellbar example, in the edge of a circular opening of a sheet metal container. The occlusion bed 7 is connected via a flexible bellows 4 with a Balgausgießer 3, which is a more or less cylindrical part, whose upper portion is formed by a threaded connector 3a. The free when using outflow of Balgausgießers 3 is closed by an unspecified designated seal with tear-off ring.

p0015In Figure 1, the screw 1 is a little further and hatching compared with the closure portion with opposite inclinations. The screw 1 consists of the so-called cap base 14, one or two fold-pull brackets 15, a cylindrical portion 16 with an internal thread and a cylindrical seal projection 20, which engages sealingly into the threaded socket 3a, while the cylindrical portion 16 is screwed onto the external thread of the threaded connector 3a ,

p0016It can be seen in the lower part of Figure 1 left only the teeth 5 of the threaded connector 3a and the Balgausgießers 3 while additionally the teeth 2 of the screw 1 recognizes the right. The section plane AA in Figure 1 passes exactly through the area of ​​the teeth so that the teeth or tooth elements 2, 5 are clearly visible in FIG. 2 It can be seen that both the teeth 2 and the teeth 5 have an asymmetric profile with a gentle slope and a steep flank, wherein the flat flanks of the teeth 2, 5 easily slide on each other, so that due to the elasticity of the plastics from which the parts 1, 6 consist, the tooth elements 2, 5 jump over each other. In the opposite direction, however, enter the steep flanks of the teeth 2, 5 engaged with each other, thus preventing any unscrewing of the cap 1 of the closure portion 6 and the threaded connector 3a.

p0017In figure 2 also the indentations designated by 12 can still be seen in a thread ridge 11 which define the intermediate teeth 2 and which are more clearly in Figure 3 in a perspective view seen.

p0018With respect to the parts described so far corresponds to the container closure of Figures 1 to that of Figures 1 and 2 in DE-44 00 993.3. Notwithstanding that, however, protrusions 17 are provided diametrically opposite and radially outwardly projectingly provided on the lower portion of the threaded connector 3 in the present invention. In Figure 1, is one such threaded connector 17, which is located on the non-visible in this representation outside of the threaded connector 3, indicated by dashed lines in outline. According to the sectional view AA, the two diametrically opposite projections 17 in an axial plan view can be seen in FIG. 2 The two projections 17 are offset by 90 ° with respect to the teeth 5 of the threaded connection 3rd A radial depression of the threaded connection 3 in the region of the teeth 5, however, is still possible, even if the projections 17 abut with their radially outer surface to the inner surface of the screw cap. 1 As can be seen, is between the teeth 5 and the projections 17 enough space, can in which the deforming threaded connector 3 to go when a radially pressing the areas takes place with the teeth 5 to unscrew the screw cap 1 can. Should be noted, in this connection, that corresponding to the view AA, the figure 2 represents a left-hand thread, because in the opening direction, the steep edges of the teeth 2, 5 must lie against one another, while the inclined surfaces of the gear teeth come in the closing direction engage with each other, so that when the closure screwing can slide the flanks of the teeth together. For a right-hand thread, the arrows A shown in Figure 1 would have from the bottom up, according to a view on the cut surface from below. This view, however, the projections 17 would not be visible, so that here the view is selected from the top.

p0019Figure 3 shows a screw cap according to a variant of the present invention. This screw 1 'in figure 3 differs from the screw 1 in the figures 1 and 2 only in that it has an inwardly projecting protrusion 17' has, which, like the teeth 2 in extension of a thread, but as close to the the bottom of the screw cap is placed. The position of the projection 17 'corresponds exactly to the position which is occupied otherwise by the outwardly facing projection 17 of the threaded connector in a completely screwed onto the threaded connector 3 cap. Insofar substantially satisfy both projections 17 and 17 'have the same function by namely ensuring that the screw neck 3 that is pushed back to a previous deformation essentially back to its largely circular cross-sectional shape by screwing the screw cap. 1

p0020Otherwise, the screw 1 is shown in Figure 3. in the same sectional view as in Figure 1, but with the closure portion 6 is omitted, so that the views of the threaded inner wall of the screw cap 1 is released. As can be seen, which have inwardly protruding thread ridges 11, a trapezoidal profile with a band-like circumferential, flat thread surface 13. The lower end portion of the threaded web 11 has a series of notches 12 which have already been described in the radial cross-sectional view in connection with FIG 2, and defining the teeth 2 in the form of remaining between the notches 12 regions of the thread ridge 11th The axial length H of the thread ridge 11 and thus, the minimum width of the teeth 2, which engage with corresponding teeth 5 of the lower closure part 6, is at least 0.5 mm, but preferably should be more than 1 mm. As can be seen, the screw 1 has no bulge, extension or other additional space, because ultimately the teeth 2 defined only by recessed areas 12 in a present anyway thread web 11th At the corresponding threaded connector 3a and on the cylindrical Balgausgießer 3, of which the threaded connection forms a portion 3a, the teeth 5 are provided, which engage with the teeth 2 on the respective teeth 2 axial height. In this case, the thread of the threaded stub 3a readily may extend into the region of these teeth 5, ie, the teeth 5 could readily 3a also define the lowermost portion of the thread of the threaded stub.

p0021Although the teeth 2 and the projection 17 are in figure 3 'in almost the same axial level located, but preferably should the teeth 2 lie axially in figure 3 above, while the projection 17' be positioned as close to the bottom 10 of the screw cap 1 should.

p0022In a variant shown in Figure 4, the lower edge 10 of the screw cap 1 each in the range of gears 2 has an axially recessed recess 19th This recess 19 provides a view onto the teeth 5 of the threaded connector 3 when the screw cap is 1 screwed firmly onto the threaded connector 3 since then engage the teeth 2 and 5 into one another and thus are in the same range as the axial grooves 19. In this way, you can also take the fingers of one hand the toothed portion of the screw neck lighter and especially the pressing force exert relatively close to the engagement with the teeth 2 of Schraubkappenverzahnung. This makes it possible relatively safe and without too much effort, the screw neck 3 in the region of its teeth 5 compress the extent that they come with the teeth 2 of the screw cap is disengaged.

LIST OF REFERENCE NUMBERS

p0023<dl id="dl0002" compact="compact"><dt>1,</dt><dd>1 'screw</dd><dt>2</dt><dd>gearing</dd><dt>3</dt><dd>Balgausgießer</dd><dt>3a</dt><dd>threaded connector</dd><dt>4</dt><dd>bellows</dd><dt>5</dt><dd>gearing</dd><dt>6</dt><dd>Closure portion</dd><dt>7</dt><dd>closure foot</dd><dt>10</dt><dd>edge</dd><dt>11</dt><dd>thread web</dd><dt>12</dt><dd>notches</dd><dt>13</dt><dd>threaded surface</dd><dt>14</dt><dd>cap base</dd><dt>15</dt><dd>excerpt Ironing</dd><dt>16</dt><dd>cylindrical member</dd><dt>17</dt><dd>seal approach</dd><dt>17,</dt><dd>17 'projections</dd><dt>19</dt><dd>recess</dd></dl>