CONTAINER SEAL CLOSURE AND ASSEMBLY
A seal closure for a container includes a closure body and a plug liner. In embodiments, the closure body includes an upper wall, an outer annular wall, a radially outer support portion, and a radially inner support portion. The outer annular wall includes formations configured to engage a neck portion of a container. The plug liner may be configured to extend radially across the radially inner support portion. A hollow space can be formed by and provided between the plug liner, the radially inner support portion, and the upper wall. Embodiments of the closure may also include a plug seal. A method for designing or configuring a closure to accommodate or displace a headspace associated with a container is also disclosed.
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This application claims the benefit of U.S. Provisional Application No. 61/595,882, filed Feb. 7, 2012, which is incorporated by reference as though fully set forth herein.
TECHNICAL FIELDThis invention relates generally to closures for containers, including closures and closure assemblies suitable for use in connection with hot-fill applications.
BACKGROUNDPlug-type closures can fill in headspace associated with containers. Headspace generally comprises an area provided between the fill level of the product contents and the associated cap. In applications, a secondary vacuum can build up with an absorption of remaining headspace by product contents. The fill level can rise as a result of the associated vacuum, but will generally stabilize when the level comes into contact with the plug. With traditional closure systems the structure of the bottle may be configured to resist the vacuum associated with nearly all of the headspace.
Plug seal closures can provide a useful option to reduce gram weight by employing a thinner neck (or “E-wall”). However, with a thinner E-wall, a conventional container can be more prone to ovalization or warping, particularly with hot-fill applications. It is desirable to provide a container closure and assembly that can serve a dual purpose of providing a sealing function and protecting the neck (e.g., serving as a form of insulator). It can further be desirable to provide closures that, inter alia, may provide:
(a) a lower fill level at opening for consumer convenience than traditional fill level specifications used to minimize headspace;
(b) less/smaller oxygen (O2) headspace content (which can provide better product quality);
(c) improved resistance to bottle-to-bottle contact pressure when product contents reach an associated plug;
(d) improved resistance to denting and ovalization under secondary vacuum when product contents reach an associated plug; and/or
(e) opportunities for potential light-weighting.
SUMMARYWith embodiments a closure assembly includes a closure with a plug insert that inserts itself into the headspace of a container and displaces it, which can thereby move an associated fill level closer to the cap. Having the fill level closer to the cap can generate more internal pressure and greater container stability.
Embodiments of the invention will now be described, by way of example, with reference to the accompanying drawings, wherein:
Reference will now be made in detail to embodiments of the present invention, examples of which are described herein and illustrated in the accompanying drawings. While the invention will be described in conjunction with embodiments, it will be understood that they are not intended to limit the invention to these embodiments. On the contrary, the invention is intended to cover alternatives, modifications and equivalents, which may be included within the spirit and scope of the invention.
It is noted that the plug liner 80 may extend vertically below the lowermost vertical point of the radially inward support portion 60 (e.g., as illustrated in
As generally illustrated, a hollow space 90 may be formed by and provided between the plug liner 80, the radially inner support portion 60, and the upper wall 30. Additionally, as generally shown, the inclusion of the plug liner 80 will serve to displace headspace (typically atmosphere or air residing above the container contents) in connection with a closed/sealed container. The closure 10 may be produced by various methods known in the art, including injection molding, co-injection molding, and/or compression molding.
By configuring and/or adjusting the plug liner 80 and hollow space 90, the closure can be configured to accommodate or displace a headspace associated with a container. Digital models (e.g., computer or CAD models of the components) may be generated and adapted to provide a design for a closure with plug liner and/or a hollow space to address desired container fill levels or other objectives. In embodiments, a digital model for a seal closure having an upper wall, an outer annular wall, a radially outer support portion, and a radially inner support portion can be created or generated. A digital representation of a plug liner and hollow space may be included with the digital model of the closure. Various elements of the digital model can be adjusted or configured to meet desired objectives. For example and without limitation, (i) the volume of the hollow space, (ii) the size and/or the shape of the plug liner, or both (i) and (ii) may be adjusted or configured to meet an anticipated container fill condition. Aspects of the aforementioned process can be used to provide a closure for a container that minimizes an associated headspace. With brief reference to
As generally illustrated in
It is noted that the foregoing concepts may be used in connection with various other hot-fill related container system techniques that address internal pressures and/or vacuum forces, including post-sealing techniques. For example, closures such as described herein may be used in connection with techniques for heating and/or pressurizing plastic containers disclosed in U.S. patent application Ser. No. 12/702,370, filed Feb. 9, 2010, and U.S. Pat. No. 7,735,300, published Jun. 15, 2010, which are incorporated herein in their entirety by reference. For instance, heating, pressurizing and/or other hot-fill related techniques can be additionally employed to provide further vacuum absorption post-sealing, while the inclusion of a plug liner can serve to reduce the associated headspace to be offset. While some post-sealing processes can increase the internal pressure by displacing headspace, by employing closures with features as described herein, less headspace may need to be addressed.
For example, and without limitation, in an embodiment of a system, a container may be hot-filled with contents and a closure with sealing features (such as disclosed herein) may be applied to seal the container. Then, a post-sealing process for dealing with vacuum absorption (e.g., heating/pressurizing) may be applied to the sealed container. For some embodiments, the maximum distance between the fill level after post-sealing treatment (e.g., heating/pressurizing) and the plug is kept to about 2 mm±1.5 mm.
Although numerous embodiments of this invention have been described above with a certain degree of particularity, those skilled in the art could make numerous alterations to the disclosed embodiments without departing from the spirit or scope of this invention. It is intended that all matter contained in the above description or shown in the accompanying drawings shall be interpreted as illustrative only and not limiting. Changes in detail or structure may be made without departing from the spirit of the invention as defined in the appended claims.
Claims
1. A seal closure for a container, the closure comprising:
- a closure body including an upper wall, an outer annular wall, a radially outer support portion, and a radially inner support portion; the outer annular wall including formations configured to engage a neck portion of a container; and
- a plug liner, the plastic plug liner extending radially across the radially inner support portion;
- wherein a hollow space is formed by and provided between the plug liner, the radially inner support portion, and the upper wall.
2. The seal closure of claim 1, wherein the radially inner support portion and the plug liner are formed as a unitary component.
3. The seal closure of claim 1, wherein the plug liner extends vertically downward below the radially inner support portion.
4. The seal closure of claim 3, wherein the plug liner extends vertically downward a distance that is about the same or greater than a distance that the lowermost point of the radially inner support portion extends vertically downward from the upper wall.
5. The seal closure of claim 1, wherein the plug liner is substantially fixed and rigid.
6. The seal closure of claim 5, wherein the plug liner is configured to substantially resist flex-inducing forces.
7. The seal closure of claim 1, wherein the plug liner has a wall thickness that is at least as thick as a wall thickness of the radially inner support portion.
8. The seal closure of claim 1, wherein the plug liner is comprised of plastic.
9. The seal closure of claim 1, including a plug seal provided at or adjacent the upper wall and radially between the radially outer support portion and the radially inner support portion.
10. The seal closure of claim 1, wherein the plug seal is comprised of plastic.
11. The seal closure of claim 10, wherein the plug seal is comprised of thermoplastic elastomer or ethylene vinyl acetate.
12. A method for designing or configuring a closure to accommodate or displace a headspace associated with a container, the method comprising:
- creating or generating a digital model of a seal closure with a closure body including an upper wall, an outer annular wall, a radially outer support portion, and a radially inner support portion; and
- creating or generating a plug liner in or with the digital model such that the plug liner extends radially across the radially inner support portion to form a hollow space between the plug liner, the radially inner support portion, and the upper wall.
13. The method of claim 12, including adjusting the volume of the hollow space.
14. The method of claim 13, wherein the volume of the hollow space is sized or configured with respect to an anticipated container fill level.
15. The method of claim 12, including adjusting the size or shape of the plug liner with respect to an anticipated container fill level.
16. The method of claim 13, including a digital representation of a plug seal with the digital model, the plug seal provided at or adjacent the upper wall and radially between the radially outer support portion and the radially inner support portion.
17. The method of claim 12, including physically forming or manufacturing a closure with a plug liner and hollow space in accordance with the digital model.
18. The method of claim 16, including physically forming or manufacturing a closure with a plug liner, hollow space, and plug seal in accordance with the digital model.
Type: Application
Filed: Feb 7, 2013
Publication Date: Aug 8, 2013
Applicant: Plastipak Packaging, Inc. (Plymouth, MI)
Inventor: Plastipak Packaging, Inc. (Plymouth, MI)
Application Number: 13/761,652
International Classification: B65D 41/00 (20060101);