EP1144254B1 - Closure cap - Google Patents

Abstract

The closing cap has a bulge (6) in the transition region (7) between the cap top (2) and the cap skirt (3) to press a sealing washer (5) against the container mouth. The bulge has an undercut (8), and is divided into sectors by weakening points (10) to give the bulge radial flexibility. The undercut mar extend into a region spaced out from the inside (15) of the cap top.

Description

The invention relates to a closure cap with the features the preamble of the independent claim. Such Plastic closures are known and are also used to close containers carbonated drinks used.

There are many different arrangements for achieving one Seal between the cap and the container mouth known. In a known sealing variant, the seal with a sealing washer placed on the inside of the cap base achieved by the cap bottom against the container mouth is pressed.

It is important that especially in the area of the outer edge the container mouth a good pressure of the sealing washer is achieved.

Such a closure is, for example, from EP 55 916 known. The sealing washer is a protrusion in the Targeted area between the cap base and the cap apron against the upper outer edge of the mouth of the container pressed. In this way, a pressure is applied high surface pressure and thus a good sealing effect.

If there is excessive pressure inside the bottle, for example by fermentation or heating, there is Danger of the container breaking or the cap jump off. Various attempts have already been made made to solve this problem.

From EP 370 272 it is known, for example, that rotating Partially rib to press on the sealing washer interrupt. The sealing washer can be in the area of the interruptions avoid overpressure and thus a reduction of the Allow pressure in the container. The construction according to EP 370 272 has the disadvantage that in the areas the interruption do not touch the sealing washer at all outer edge is pressed. This can cause leakage lead even if there is no increased pressure in the container is.

From US 4,629,083 (corresponds to the preamble of claim 1) and from EP 770 559 is also a cap is known in which the bead, which the sealing washer should not press against the neck of the container as a thickening in the transition area between the cap base and the cap apron is arranged, but as axially after protruding circumferential rib below. With this construction there is the problem that the pressure due to the Gaps between the rib and the inside of the cap apron is not very strong. These two constructions also solve the problem of container bursting increased internal pressure also not.

It is therefore an object of the present invention that To avoid disadvantages of the known, in particular one To create a sealing cap, which in the case of increased internal pressure Container in the manner of a pressure relief valve works, i.e. allows the gas release, which is still at normal internal pressure seals reliably and which is simple and economical can be produced.

According to the invention, these tasks are in the present Cap by the characteristics of the characteristic part solved by claim 1.

The cap for a container has a cap base and a cap apron. The cap apron is provided with inner retaining means, which can be brought into engagement with outer retaining means at the mouth of a container. The cap can have, for example, a screw thread or a snap or bayonet thread. The cap can be used advantageously for drinks containing CO ₂ or for hot-filled drinks.

The cap also has a sealing washer which lies at least partially on the cap base. Of course is also a non-continuous sealing insert, for example a sealing ring conceivable. The cap has also in the transition area between the cap base and the cap apron a circumferential bead for pressing the Sealing washer on the upper, outer edge of the mouth of the Container. The sealing cap is between the bead and the apron at least partially with a circumferential undercut Mistake. The undercut can be evenly over 360 degrees over the circumference of the closure cap extend.

However, the undercut is also conceivable only in segments train. The bead is also in at least one provide a segment-shaped section with a weakening. The Combination of a circumferential bead with an undercut and leads to a weakening in segment-like sections to a particularly good sealing effect, which nevertheless Relief of overpressure allowed.

Because the bead runs all the way around in the transition area formed between the cap bottom and the cap apron the sealing washer is pressed on evenly to the container mouth. The undercut gives some flexibility at the bottom of the bead, so that the bead when pressure is applied to the outside is bendable. By choosing the size of the undercut can be the pressure at which the internal pressure is released be precisely predetermined. The weaknesses in the bead confer a larger one in the predetermined sections radial flexibility. In these sections, the sealing washer with increased internal pressure, be pushed outwards. A blow off is possible.

The undercut preferably extends from the lower one Edge of the bead in an area, the distance to the cap bottom having. This means that the bead is in the transition area continuous between the cap bottom and the cap wall is trained.

In a particularly preferred embodiment, the Weakening of the bead due to depressions on the outside of the bead which faces the cap apron. This creates segment-like weakenings without there is an irregular contact surface. The contact surface, which the sealing washer against the outer upper Pressed on the edge of the container mouth thus extends over 360 degrees and is essentially flat, i.e. she has none Deepenings or elevations. The wells on the Outside of the bead still give the bead in predeterminable Areas increased radial flexibility.

Of course, it is also conceivable to use other types of To provide for weakenings. For example, the bulge can pass through different choice of material, different orientation of the material or be weakened by different density of the material.

In an alternative embodiment, the weakening is of the bead formed by depressions that extend from the lower Extend the end of the bead axially against the cap base and which preferably extend over the entire thickness of the bead. Because the depressions don't extend to the top End of the bead but only extend towards the base of the cap, the disadvantages of a bead with continuous Avoid interruptions according to the prior art.

The weakening advantageously extends approximately over the height the undercut. In the area between the lower end of the bead and the end of the undercut is the bead flexible. The weakening is special in this area effective.

The sections which have weakening of the bead preferably comprise in total (i.e. the sum of all sections together) an angular range of 90 ° to 220 °. There are preferably about 3 to 15 sections with weakenings intended.

The cap base can be opened to increase the blow-off function its inside also with at least one radial Be provided depression that radially least over extends a sealing portion of the cap bottom. The sealing section defines the zone of the cap base which presses the sealing washer against the container mouth. by virtue of the recess in the cap base can be the sealing washer be displaced axially upwards and thus a way to dismantle form an overpressure. In a particularly preferred one Embodiment aligns the radial recess in the radial Seal with a weakening of the bead.

In a further exemplary embodiment, the cap base is open provided on the inside with a circumferential rib that runs concentrically to the cap. The circulating Rib serves to increase the contact pressure of the sealing washer. In addition, there can also be radial ribs on the cap base be provided. The radial ribs are preferred higher than the circumferential rib. In this case the radial depressions are dispensed with. It has found that the provision of such radial ribs especially with hot fillings, for example with fruit juices, is advantageous. Because of the heat, the Sealing washer softer and there is usually a risk of that the sealing washer is pulled radially inwards. With the radial ribs and with the circumferential rib this becomes avoided.

Figur 1

einen Querschnitt durch eine erfindungsgemässe Verschlusskappe,

Figur 2

schematische perspektivische Darstellung eines Ausschnitts einer erfindungsgemässen Verschlusskappe

Figur 3

Untenansicht einer erfindungsgemässen Verschlusskappe ohne Dichtscheibe

Figuren 4a und 4b

zwei Ausführungsbeispiele der Schwächung des des Wulstes, und

Figur 5

eine Verschlusskappe gemäss Figur 4a auf einem Behälter mit erhöhtem Innendruck.

The invention is explained below in exemplary embodiments and with reference to the drawings. Show it:

Figure 1

3 shows a cross section through a closure cap according to the invention,

Figure 2

schematic perspective view of a section of a closure cap according to the invention

Figure 3

Bottom view of a closure cap according to the invention without a sealing washer

Figures 4a and 4b

two embodiments of the weakening of the bead, and

Figure 5

a closure cap according to Figure 4a on a container with increased internal pressure.

Figure 1 shows a closure cap 1 according to the invention Cross-section. The cap 1 is essentially from a cap base 2 and a cap apron 3, which in a transition area 7 meet. The cap is provided with an inserted sealing washer 5, which rests on the inside of the cap base 2. The Sealing disc is used to seal a container mouth schematically illustrated container 20th

In the transition area 7, a bead 6 is provided, which Sealing disc 5 against the upper edge 22 of the container 20th presses.

Between the bead 6 and the inside of the cap apron 3 an undercut 8 is provided which corresponds to the lower one End 14 (see Figures 3 and 4) increased radial flexibility gives. According to the invention, the bead 6 is in the area the undercut 8 provided with weakenings 10. The Weakenings 10 impart the bead 6 in selected sections 9 (see Figures 2 to 4) an additionally increased radial flexibility.

The sealing disc 5 is in a sealing area 17 from the cap bottom 2 pressed against the container mouth. Once inside of the container creates an increased internal pressure Cap base 2 pressed up, whereby the sealing washer in Sealing section 17 is relieved of pressure. Because of the weakening 10 in the bead 6, the sealing washer 5 in the area Sections 9 with weakenings pressed radially outwards and the increased internal pressure is reduced.

The cap can also be used with other caps provide known, constructive details his. In Figure 1, a guarantee tape 19 is shown, which to indicate unauthorized opening of the closure. Furthermore the closure cap is provided with ventilation cutouts 18, which favor the gas discharge.

FIG. 2 shows a section of the closure cap according to the invention 1 shown in perspective without a sealing washer. The segment-like sections 9 can be seen in FIG which the bead 6 is provided with weaknesses 10. The Attenuations 10 are formed as depressions 12, which are arranged on the outside 13 of the bead 6.

Together with the undercut 8 lead the recesses 12 for radial flexibilization of the bead 6.

The inside 15 of the cap base 2 is also provided with radial ribs 16. The radial ribs 16 extend at least over the sealing section 17, in which a sealing disk 5 (see FIG. 1) can be pressed against a container mouth. The cap base 2 is also provided with a circumferential rib 23 which increases the pressure on the sealing disk 5 in the area outside the radial recesses 16. The height h _{1 of} the radial ribs 16 is greater than the height h _{2 of} the circumferential rib 23.

A closure cap according to the invention is shown in FIG Sealing washer shown from below. The circumferential bead 6 has a continuous inside. On the outside 13 of the Beads 6, which is directed against the cap apron 3, the bead 6 is provided with depressions 12. The wells 12 lead to weakening of the bead 6 in segment-like Sections 9. The depressions 12 are even over the distributed over the entire circumference of the closure cap. They extend each over an angular range of approximately 5 ° to 40 °. Furthermore radial ribs 16 are shown in the cap base 2, which end between the wells 12. On the inside of the cap base 2 is also shown a circumferential rib 23, which in the sealing section 17, the not shown Press the sealing disk 5 against the container mouth. The undercut 8 between the cap apron 3 and the bead 6 gives the bead 6 in combination with the depressions 12 increased flexibility in the direction of the arrow r.

Various exemplary embodiments are shown in FIGS. 4a and 4b shown to form the weakenings 10 of the bead 6.

In FIG. 4a, the bead 6 is only on the outside 13, which is directed against the cap apron 2, with a Provide depression 12. The recess 12 extends from lower end 14 axially against the cap base 2. The undercut 8 has a height h. The end of the undercut 8 is at a distance from the inside 15 of the cap base 2. This means that the bead 6 in the transition area 7 between the cap apron 2 and the cap base 3 continuously formed between the cap base and the apron is. The sealing washer 5 is against a by the bead 6 mouth of a container 20 only shown schematically pressed.

FIG. 4b shows an alternative embodiment of the Invention shown. The recess 12 ', which is the weakening 10 in the bead 6 is continuous in the radial direction educated. Otherwise the embodiment corresponds according to FIG. 4b the example from FIG. 4a.

FIG. 5 shows the exemplary embodiment according to FIG. 4a shown a container with increased internal pressure. Because of the the cap bottom 2 is increased internal pressure in the container 20 axially curved outwards (so-called doming). This will the sealing washer 5 is relieved of pressure in the sealing section 17, so that gas can escape. Because of the weakening 10 of the bead 6 can the bead and thus the sealing washer 5 in the direction of the arrow r be pushed radially outwards, causing gas can also escape in this area. In dashed lines The position of the bead in normal position is shown by lines. In the circumferential sections outside the sections 9 with weakenings 10 the bulge 6 assumes this original position. The Venting therefore only takes place in segments and is therefore precise controllable. In the remaining sections there is the contact pressure the sealing disc 5 is still so large that a seal is guaranteed.

Claims (8)

1. A closure cap (1) for a container (20),
   with a cap base (2) and
   with a cap skirt (3), with inner retaining elements (4) which may be brought into engagement with outer retaining means of the opening of the container (20),
   with a sealing disk (5) which at least partly bears on the cap base (2)
   and with a circumferential bulge (6) in the transition region (7) between the cap base (2) and the cap skirt (3), for pressing the sealing disk (5) onto the upper outer edge (22) of the opening of the container (20),
   whereby the closure cap (1) between the bulge (6) and the skirt (3) at least partly is provided with a circumferential undercut (8),
   characterized in that the bulge (6) in at least one segment-like section (9) comprises a weakening (10).
2. A closure cap (1) according to claim 1, characterised in that the undercut (8) extends up to into a region which is distanced to the inner side (15) of the cap base (2).
3. A closure cap according to one of the claims 1 or 2, characterised in that the weakening (10) of the bulge (6) is formed by deepenings (12) on the outer side (13) of the bulge (6), which faces the cap skirt (3).
4. A closure cap according to one of the claims 1 to 3, characterised in that the weakening (10) of the bulge (6) is formed by deepenings (12') which extend from the lower end (14) of the bulge (6) axially against the cap base (2) and which extend preferably over the whole thickness (d) of the bulge.
5. Closure caps according to one of the claims 1 to 4, characterised in that the weakenings (10) extend roughly over the height (h) of the undercut (8).
6. A closure cap according to one of the claims 1 to 5, characterised in that the sections (9) with a weakening (10) as a whole have an angular range of 90° to 220°, wherein preferably 3 to 15 sections (9) are provided with a weakening (10).
7. A closure cap according to one of the claims 1 to 6, characterised in that the cap base (2) on its inner side (15) comprises at least one radial rib (16) which radially extends at least over a sealing section (17) of the head plate (2), and that the cap base optionally comprises a circumferential rib (23), wherein the height (h₁) of the radial rib (16) is larger than the height (h₂) of the circumferential rib.
8. A closure cap according to claim 7, characterised in that the radial rib (16) ends between neighbouring weakenings (10) of the bulge (6).

Images