Patent Application
20220234789
The present invention relates to a closure, especially a closure for containers for liquids. In particular, the invention relates to a closure for neck finishes of blow molded containers.
Containers for large volumes of liquids such as e.g. containers for washing agents or milk bottle are often blow molded plastic containers. A disadvantage of these blow molded containers are geometric inaccuracies and seams at the opening of the container which complicate the positioning of the closure on the neck finish and hence the reliable sealing of the individual container opening.
It is an object of the invention to provide a closure with an improved sealing which compensates geometric inaccuracies of the neck finish of the liquid container.
The invention relates to a closure for sealing a neck finish of a liquid container. The closure comprises a top deck and an outer skirt extending from the top deck in an axial direction away from the top deck comprising at least one locking means (respectively locking structure) for engaging the closure to the neck finish of the liquid container. The locking means can be a thread arranged on the outer skirt or a snap lock to snap the closure on the neck finish. Other locking means are also possible. Depending on the application, the closure may further comprise a hinge.
A deformable primary sealing lip is arranged on an inner surface of the top deck and extends, respectively protrudes, in a circumferential manner along the inner surface of the top deck. The primary sealing lip is preferably deformable with respect to the top deck. With respect to its cross-section the primary sealing lip comprises a dorsal end connected to the inner surface of the top deck and a free distal end arranged opposite to the dorsal end. Preferably, the primary sealing lip has in the cross-section an elongated shape extending from the dorsal end towards the distal end featuring a first and a second side (opposite of the first side) in between the dorsal end and distal end. Furthermore, the primary sealing lip is arranged with respect to its cross section in an inclined manner facing inwardly (in the radial direction towards a center axis of the closure; the center axis extending in the axial direction, perpendicular to the radial direction). Hereby, the second side of the primary sealing lip is facing the inner surface of the top deck.
Preferably, the primary sealing lip features in an undeformed position (before initially applying the closure on the neck finish) a larger inclination angle than in a deformed position (after initially applying the closure on the neck finish). The inclination angle is thereby defined between the primary sealing lip and the inner surface of the top deck facing radially inwards (towards the center axis). Depending on the application, the first and/or the second side of the primary sealing lip may be essentially straight in the undeformed position, e.g. the primary sealing lip may have a rectangular cross-section in the undeformed position. Hence, the inclination angle is essentially uniform over the primary sealing lip. However, also curved embodiments of the first and/or second sides are possible in the undeformed position. For injection molded plastic closures a curved design is possible, as long as it is demoldable. In the case of a curved sealing lip, the inclination angle can be understood as an average angle. The primary sealing lip may be at least partially plastically deformable, such that a deformed position of the primary sealing lip is maintained after initially applying the closure to the neck finish. An inclination angle of the primary sealing lip in the undeformed position can be i.g. in the range of α=30-60 deg (degree). The (average) inclination angle of the primary sealing lip in the deformed position and in the applied position of the closure on the neck finish may be in the range of α=10-50 deg, however other angles are also possible. To facilitate the deformation of the primary sealing lip, the primary sealing lip may further comprise a thinning at the dorsal end with respect to the cross-section of the primary sealing lip, close to the inner surface of the top deck.
Preferably, at least one supporting element protrudes from the inner surface of the top deck, configured to support the primary sealing lip with respect to the neck finish in an applied position of the closure. The supporting element is arranged coaxially to the primary sealing lip to provide a uniform sealing over the circumference. Furthermore, the supporting element may be arranged on the inner surface of the top deck at least partially inside of the primary sealing lip. Preferably, the supporting element is in a radial direction arranged closer to the center axis of the closure than the primary sealing lip. Depending on the application, the supporting element may also be deformable. In an applied position of the closure, the at least one supporting element, is advantageously at least partially arranged within a projection area of the deformed primary sealing lip in the axial direction and on the inner surface. In that way, the supporting element is connected to the inner surface of the top deck in the radial direction between the distal end and the dorsal end of the deformed primary sealing lip in an applied position of the closure.
When the closure is applied for the first time, the primary sealing lip preferably engages first with the distal end with a rim of the neck finish. If the closure is applied further (e.g. the closure may be screwed further down on the neck finish) the primary sealing lip begins to deform and establishes a surface contact along the first side of the primary sealing lip. As the application pressure of the closure increases the primary sealing lip further bends radially inwards and engages with the supporting element on its second side. When the closure is fully applied, the primary sealing lip has preferably a surface contact at least partially along the first side of the primary sealing lip and is in contact with the inner edge of the rim of the neck finish. On the second side, the primary sealing lip is in contact with the at least one supporting element. The supporting element thereby supports the contact of the primary sealing lip against the rim by increasing the pressure on the inner edge of the rim. The overall sealing of the closure against the neck finish is thus enhanced. In the applied position of the closure a chamber may be formed between the primary sealing lip and the at least one supporting element. Enclosed air in the chamber thereby increases the sealing quality since it contributes to the deformability of the primary sealing lip around the rim of the neck finish.
Depending on the application, the at least one supporting element may be a secondary sealing lip, which is also inclined radially inwards, facing away from the outer skirt, as described for the primary sealing lip. Respectively, the secondary sealing lip may also be deformable. For good sealing qualities the outer rim of the neck finish in the axial direction can be arranged in the radial position between the dorsal end of the primary sealing lip and a distal end of the secondary sealing lip with respect to a cross section of the (primary and secondary) sealing lips in the undeformed position before initially applying the closure.
In another variation of the closure according to the invention, the at least one supporting element may be a circumferential first bump. Furthermore, the closure may comprise a circumferential second bump as a second supporting element arranged radially inwards of the circumferential first bump which extends along the primary sealing lip. For a uniform sealing along the circumference of the neck finish, the circumferential first bump is preferably arranged coaxially to the circumferential second bump. Good results can be achieved, if the circumferential second bump has a larger height in axial direction and in respect to the inner surface of the top deck than the circumferential first bump. Preferably, the circumferential first and second bump are arranged at least partially within the projection area of the inclined and deformed primary sealing lip on the inner surface in an applied position of the closure. In that case, the circumferential first and the second bump each connected via a base to the inner surface of the top deck, are arranged with their bases at least partially between the distal end and the dorsal end of the deformed primary sealing lip in an applied position of the closure.
The primary sealing lip and the at least one supporting element may be formed as an integral part of the closure or can be interconnected to the top deck as a separate element. Preferably, the closure is made by a (first) plastic material, in particular an injection molded plastic material. Thereby, the primary sealing lip and/or the supporting element may be made at least partially of a second plastic material, which is softer than the (first) plastic material of the other closure parts. The first and the second plastic material may injection molded in a two material injection molding process.
It is to be understood that both the foregoing general description and the following detailed description present embodiments, and are intended to provide an overview or framework for understanding the nature and character of the disclosure. The accompanying drawings are included to provide a further understanding, and are incorporated into and constitute a part of this specification. The drawings illustrate various embodiments, and together with the description serve to explain the principles and operation of the concepts disclosed.
The herein described invention will be more fully understood from the detailed description given herein below and the accompanying drawings which should not be considered limiting to the invention described in the appended claims. The drawings are showing:
Reference will now be made in detail to certain embodiments, examples of which are illustrated in the accompanying drawings, in which some, but not all features are shown. Indeed, embodiments disclosed herein may be embodied in many different forms and should not be construed as limited to the embodiments set forth herein; rather, these embodiments are provided so that this disclosure will satisfy applicable legal requirements. Whenever possible, like reference numbers will be used to refer to like components or parts.
If the closure 1 is applied for the first time on a neck finish 2 of the liquid container, the primary and the secondary sealing lip 6, 13 are deformed. Preferably, the primary and the secondary sealing lip 6, 13 are at least partially plastically deformed, such that a deformed position at least of the primary sealing lip 6 is maintained after initially applying the closure 1 to the neck finish 2.
In the illustrated second variation, the primary sealing lip 6 is combined with two supporting elements 10: A circumferential first and second bump 14,15. The circumferential first and second bump 14,15 are arranged on the inner surface 7 of the top deck 3, extending from said top deck 3. Furthermore, the primary sealing lip 6 and the circumferential first and second bump 14,15 are arranged coaxially with respect to each other. In particular, the circumferential first and second bump 14, 15 are preferably arranged at least partially within the projection area 12 of the inclined primary sealing lip 6 on the inner surface 7 in an applied position of the closure 1 (projection is indicated by dashed line). As it can be seen, the first and the circumferential second bump 14,15 may have different heights (in the axial direction) in respect to the inner surface 7 of the top deck 3. Good sealing results may be achieved, if the circumferential second bump 15 arranged radially inwards of the circumferential first bump 14 extends in axial direction further away from the inner surface 7 than the circumferential first bump 14.
The words used in the specification are words of description rather than limitation, and it is understood that various changes may be made without departing from the spirit and scope of the invention.
| Number | Date | Country | Kind |
|---|---|---|---|
| 00776/19 | Jun 2019 | CH | national |
| Filing Document | Filing Date | Country | Kind |
|---|---|---|---|
| PCT/EP2020/065027 | 5/29/2020 | WO | 00 |
