US20110290755A1

US20110290755A1 - Closure with impact resistant ribs

Info

Publication number: US20110290755A1
Application number: US12/789,079
Authority: US
Inventors: James M. Taber; Kevin W. Orth; Darren R. Neputy
Original assignee: Silgan White Cap LLC
Current assignee: Silgan White Cap LLC
Priority date: 2010-05-27
Filing date: 2010-05-27
Publication date: 2011-12-01

Abstract

A closure that includes a top panel and a transition section extending downwardly from a peripheral edge of the top panel is provided. The closure includes a skirt extending from a peripheral edge of the transition section such that the skirt extends away from the top panel and a plurality of raised ribs. Each of the plurality of raised ribs includes a first portion extending outwardly from an outer surface of the skirt and extending axially along at least a portion of the skirt and a second portion positioned above the first portion and extending outwardly from an outer surface of the transition section.

Description

FIELD OF THE INVENTION

The present invention relates generally to the field of closures for containers. The present invention relates specifically to closures configured for impact resistance.

BACKGROUND OF THE INVENTION

This section is intended to provide a background or context to the invention that is recited in the claims. The description herein may include concepts that could be pursued, but are not necessarily ones that have been previously conceived or pursued. Therefore, unless otherwise indicated herein, what is described in this section is not prior art to the description and claims in this application and is not admitted to be prior art by inclusion in this section.
Closures are utilized to seal or close containers for a wide variety of items including food, drink, medicine, cleaning products, etc. For many applications, integrity of the closure and integrity of the seal between the closure and the container must be maintained from the time when the container is filled and sealed until the closure is removed from the container by the end user. A closure may be subject to a variety of impact events (e.g., dropping, impact with processing machinery, impact with adjacent containers and/or shipping materials, etc.) that may causes a closure to crack or to release from the container. Such a breach in the integrity of the closure or the seal created by the closure may result in contamination, spoilage or spillage of the contents of the container.

SUMMARY OF THE INVENTION

One embodiment of the invention relates to a closure that includes a top panel and a transition section extending downwardly from a peripheral edge of the top panel. The closure includes a skirt extending from a peripheral edge of the transition section such that the skirt extends away from the top panel and a plurality of raised ribs. Each of the plurality of raised ribs includes a first portion extending outwardly from an outer surface of the skirt and extending axially along at least a portion of the skirt and a second portion positioned above the first portion and extending outwardly from an outer surface of the transition section.
Another embodiment of the invention relates to an impact resistant closure that includes a generally circular top wall and a transition section extending from a peripheral edge of the top wall. The closure includes a generally cylindrical skirt extending from a peripheral edge of the transition section such that the skirt is substantially perpendicular to the top wall and a plurality of raised ribs. Each of the plurality of raised ribs includes a first portion extending outwardly from an outer surface of the skirt and extending axially along at least a portion of the skirt and a second portion positioned above the first portion and extending outwardly from an outer surface of the transition section. The second portions of the plurality of raised ribs are configured to deform upon impact to resist failure of the closure.
Another embodiment of the invention relates to a closure configured to be coupled to a container. The closure includes a top wall, a rounded shoulder section extending from an outer edge of the top wall and a skirt extending from an outer edge of the rounded shoulder section. The closure includes at least one thread extending from an inner surface of the skirt configured for engagement with threading located on a neck portion of the container and a plurality of raised ribs. Each of the plurality of raised ribs includes a first portion extending outwardly from an outer surface of the skirt and extending axially along at least a portion of the skirt and a second portion positioned above the first portion and extending outwardly from an outer surface of the rounded shoulder section. The closure includes a tamper evident band including a frangible connecting element coupling the tamper evident band to the skirt.
Alternative exemplary embodiments relate to other features and combinations of features as may be generally recited in the claims.

BRIEF DESCRIPTION OF THE DRAWINGS

This application will become more fully understood from the following detailed description, taken in conjunction with the accompanying figures, wherein like reference numerals refer to like elements in which:

FIG. 1 is a perspective view of a closure according to an exemplary embodiment;

FIG. 2 is an enlarged perspective view of the transition section and skirt of the closure of FIG. 1, using lines 2-2 of FIG. 1 as a boundary;

FIG. 3 is a top view of the closure of FIG. 1;

FIG. 4 is a side sectional view showing the interior of the closure of FIG. 1, taken along lines 4-4 of FIG. 3;

FIG. 5 is a side sectional view showing the closure of FIG. 1 attached to a container, according to an exemplary embodiment;

FIG. 6 is an enlarged side sectional view showing the transition section of the closure of FIG. 1, taken along lines 6-6 of FIG. 7; and

FIG. 7 is an enlarged top view showing a portion of the transition section and ribs of the closure of FIG. 1.

DETAILED DESCRIPTION OF VARIOUS EMBODIMENTS

Before turning to the figures, which illustrate the exemplary embodiments in detail, it should be understood that the present application is not limited to the details or methodology set forth in the description or illustrated in the figures. It should also be understood that the terminology is for the purpose of description only and should not be regarded as limiting.
Referring to FIG. 1, a closure 10 is depicted according to an exemplary embodiment. The closure 10 includes a top panel or top portion, shown as a top wall 12. As shown, the top wall 12 is generally circular and is generally planar (i.e., the outer surface of the top wall 12 is flat lying substantially in a single plane, shown as a generally horizontal plane in FIG. 1). The closure 10 includes a skirt 14 and a transition section, shown as a corner section 16. The corner section 16 extends downwardly from the outer or peripheral edge 22 of the top wall 12, and the skirt 14 extends downwardly from the lower, peripheral edge 24 of the corner section 16.
The skirt 14 includes an upper section or portion 26, and a lower section or portion 28. As shown in FIG. 1, the upper portion 26 of the skirt 14 is generally circular in cross-section and is substantially perpendicular to the plane defined by the top wall 12 (i.e., the skirt 14 is generally cylindrical). The lower portion 28 is a frustoconical section extending downwardly and outwardly from the lower edge of the upper section 26. As shown in FIG. 1, the radius of the lower, peripheral edge of the lower portion 28 is greater than the radius of the top wall 12 or of the upper portion 26 of the skirt 14.
In the embodiment shown in FIG. 1, the skirt 14 includes a plurality of raised ribs 30 extending outwardly from the outer surfaces of the skirt 14 and of the corner section 16. As shown in FIG. 1, each of the raised ribs 30 includes a first or left sidewall 32 and a second or right sidewall 34. The left sidewall 32 and the right sidewall 34 are positioned at angles relative to the outer surfaces of the skirt 14 and of the corner section 16 such that the sidewalls converge to define an outer edge 36 of each raised rib 30. In one embodiment, the outer edge 36 is curved or rounded in the circumferential direction providing a smooth feel to the ribs 30. In other embodiments, the outer edge 36 is not rounded in the circumferential directions providing a sharp or rough feel to the ribs 30. In the embodiment shown, the ribs 30 are symmetric about the radial centerlines. In various embodiments, the ribs 30 are spaced and sized to provide improved grip during twist-on/twist-off of closure 10.
The closure 10 also includes a tamper evidencing structure, shown as tamper evident band 38 in FIG. 1. The tamper evident band 38 includes a frangible connecting element 41 (shown in FIG. 4) coupling the band 38 to the skirt 14. Upon application of twisting force to the closure 10, the frangible connecting element 41 is configured to break separating the tamper evident band 38 from the closure 10. Thus, the tamper evident band 38 provides a visual indication to the user of whether the closure 10 has previously been removed from the container to which it is attached.
Referring to FIG. 2, an enlarged perspective view of the corner section 16 and the skirt 14 of the closure 10 is shown. As shown in the exemplary embodiment of FIG. 2, the corner section 16 is a rounded shoulder segment having an outwardly curved outer surface 40. The corner section 16 extends from the peripheral edge 22 of the top wall 12 to the upper end of the skirt 14 such that the skirt 14 extends from the lower, peripheral edge 24 of the corner section 16.
As shown in FIG. 2, each of the raised ribs 30 includes a first portion 42 and a second portion 44. The first portions 42 of the ribs 30 extend outwardly from an outer surface of the skirt 14 and extend axially along the height of skirt 14. The second portions 44 of the ribs 30 are located above the first portions 42 and extend outwardly from the curved outer surface 40 of the corner section 16. As shown in FIG. 2, the second portions 44 define an outwardly curved, rounded shoulder that extends from the top wall 12 to the first portions 42 of the ribs 30. In the embodiment of FIG. 2, the first portion 42 is integral with the second portion 44 of each raised rib 30 such that each rib 30 is a continuous, radially outwardly extending structure that extends from the peripheral edge 22 of the top wall 12 along the corner section 16 and the skirt 14. The second portions 44 of the ribs 30 are positioned on the corner section 16 to provide improved impact resistance by absorbing energy that may be imparted to the closure 10 by contact with an object (e.g., another container or equipment during processing or shipment) or with a surface, such as the ground or floor, if the container having the closure 10 drops or falls. In one embodiment, the second portions 44 of the ribs 30 may be configured to deform or crumple upon impact to absorb impact energy, thereby preventing or resisting damage to the closure 10 that may otherwise be caused by the impact.
As shown in FIG. 2, the first portion 42 of each rib 30 includes a lower, flared section 46 that extends radially outward and along the frustoconical surface of the lower section 28. As shown in FIG. 2, the flared section 46 of each rib 30 is shaped such that the radius of the ribs 30 at the outer edge 36 continuously increases along the axial length of the flared section 46. In one embodiment, the closure 10 is made by an injection molding process. In this embodiment, the flared sections 46 strengthen or support the skirt 14 during axial loading of the closure that may occur during removal or ejection from the injection mold.
FIG. 3 is a top view of the closure 10. As shown in FIG. 3, the raised ribs 30 are evenly spaced along the skirt 14 and the corner section 16 (i.e., the spacing between each adjacent rib 30 is same). In the embodiment shown, the number and positioning of the ribs 30 are such that the closure 10 is essentially radially symmetric. Further, in the embodiment of FIG. 3, the closure 10 is a 43 mm closure, meaning that the closure 10 is sized to fit a container neck finish having an outer thread diameter (i.e., the diameter of the container neck measured between the outer edges of the threading) of about 43 mm. In this embodiment, the number of the ribs located on the closure 10 is 90.
As shown in FIG. 3, the closure 10 includes two locating features or pull-up marks 48. The pull-up marks 48 are located along the outer surface of the skirt 14. The pull-up marks 48 identify the position of the threading located along the inner surface of the closure 10 and provides for an indication of alignment of the closure 10 as may be needed during various processes (e.g., handling, filling of the container, capping, etc.). For example, the pull-up marks 48 act as a visible feature allowing for evaluation and inspection of closure-to-container thread interaction. As shown in FIG. 3, the ribs 30 that are positioned directly above the pull-up marks 48 do not include the lower flared section 46.
FIG. 4 is a side sectional view taken along line 4-4 shown in FIG. 3. As shown in FIG. 4, the closure 10 includes a container engagement structure, shown as threading 54. The threading 54 extends inwardly from the inner surface 56 of the skirt 14. The threading 54 is configured to engage corresponding threading present on the container to which the closure 10 is attached. In various other embodiments, the closure 10 may include other engagement structures, such as snap beads or adhesives.
As shown in FIG. 5, the closure 10 may be coupled to a container 58. In this embodiment, the container 58 includes a neck portion 60 that is open at the top end. The neck portion 60 of the container 58 includes threading 62. The closure 10 is coupled to the neck portion 60 via engagement between the threading 54 of the closure 10 and the threading 62 of the container 58 to seal or close the neck portion 60. While not shown in FIG. 5, the container 58 also includes a body sidewall and an end wall at the lower end of the body sidewall such that the container 58 is capable of holding material within an interior chamber 64 of the container 58. The container 58 may be any container that is sealed by a closure, such as the closure 10, and the container 58 may be suitable for holding a variety of contents including food, drink, etc., within the chamber 64.
FIG. 6 is an enlarged side sectional view taken along line 6-6 in FIG. 7, showing one of the ribs 30 extending from the outer surface 66 (shown in dashed lines in FIG. 6) of the skirt 14. As shown, the outwardly curved outer surface 40 of the corner section 16 (shown in dashed line in FIG. 6) is continuous with and smoothly transitions into the outer surface 66 of the skirt 14. FIG. 6 is a sectional view taken along a radial centerline that passes through the center of one of the ribs 30. As shown in FIG. 6, the outer edge 36 of the ribs 30 includes an axial segment 68 and a continuous curved segment 70. The axial segment 68 is the outer-most segment of the first portion 42 of the rib 30 that lies in the radial plane shown in FIG. 6 and defines the width of the rib relative to the outer surface 66 of the skirt 14. The continuous curved segment 70 is the outer-most segment of the second portion 44 of the rib 30 that lies in the radial plane shown in FIG. 6 and defines the width of the second portion 44 of the rib relative to the curved outer surface 40 of the corner section 16.
As shown in FIG. 6, the inner segment 72 of the continuous curved segment 70 smoothly transitions into the outer surface of the top wall 12 (i.e., the inner most segment of the continuous curved segment 70 lies in the same plane as the outer surface of the top wall 12) such that the second portion 44 of the raised rib 30 does not extend axially above the peripheral edge 22 of the top wall 12. The outer segment 74 of the continuous curved segment 70 smoothly transitions into the axial segment 68 of the first portion 42 of the rib 30 such that the second portion 44 of the rib 30 does not extend radially beyond the axial segment 68 of the first portion 42 of the rib 30. In addition, the inner surface 76 of the corner section 16 between the inner surface of the top wall 12 and the inner surface 56 of the skirt 14 is a curved fillet section.
In various embodiments, the radius of curvature R defining the continuous curved segment 70 of the second portion 44 of the rib 30 may be selected to vary the impact resistant characteristics of the ribs 30. In one exemplary embodiment, the closure 10 is a 43 mm closure and R is about 0.070 inches.
As shown in FIG. 7, the ribs 30 are symmetric about the radial centerlines. In various embodiments, the angle A between the radial centerlines of adjacent ribs 30 may be selected to vary the impact resistant characteristics of the ribs 30. In various exemplary embodiments, the angle A between radial centerlines of adjacent ribs 30 is between about 1 degree and about 7 degrees. In particular embodiments, the angle A is between about 2 degrees and about 6 degrees, and more particularly between about 3 degrees and about 5 degrees. In the exemplary embodiment shown in FIG. 7, the angle A between radial centerlines of adjacent ribs 30 is between about 3.5 and about 4.5 degrees and more specifically is about 4 degrees.
FIG. 7 also depicts the angular positioning of the left sidewall 32 and the right sidewall 34 relative the outer surface of the skirt 14. In various embodiments, the angles B and C between the radial centerline of the rib 30 and the left sidewall 32 and the right sidewall 34, respectively, may be selected to vary the impact resistant characteristics of the ribs 30. In the symmetric embodiment of the ribs 30 shown in FIG. 7, angles B and C are substantially equal to each other. In various exemplary embodiments, the angles B and C are between about 10 degree and about 50 degrees. In particular embodiments, the angles B and C are between about 20 degrees and about 40 degrees, and more particularly between about 25 degrees and about 35 degrees. In the exemplary embodiment shown in FIG. 7, the angles B and C are between about 28 and about 32 degrees and more specifically are about 30 degrees.
Referring to FIG. 7, the left sidewall 32 includes a first edge 78 at the position where the sidewall 32 meets the outer surface 40 of the corner section 16 and the outer surface 66 of the skirt 14, and the right sidewall 34 includes a second edge 80 at the position where the sidewall 34 meets the outer surface 40 of the corner section 16 and the outer surface 66 of the skirt 14. The maximum width W of the ribs 30 is the distance between the first edge 78 and the second edge 80 along the skirt 14 in a direction perpendicular to the radial centerline of the ribs 30. In various exemplary embodiments, W of the ribs 30 may be between about 0.03 inches and about 0.07 inches. In particular embodiments, W is between about 0.04 inches and about 0.06 inches, and more particularly between about 0.045 inches and about 0.055 inches. In the embodiment shown, W is about 0.05 inches.
In various embodiments, the closures discussed herein may be formed from a plastic or polymer material. In various embodiments, the closures may be formed by injection molding or by compression molding. For example, the closures may be injection molded from polypropylene homopolymer resin. In specific embodiments, the closures may be made from a clear (e.g., translucent or transparent) polypropylene homopolymer resin, or they may be made from a clear random copolymer polypropylene. In various embodiments, the clear material of the closure is such that the engagement structure (e.g., threading 54) is visible from the outside of the closure through skirt 14. Impact resistant ribs, such as the ribs 30, may allow for the closures to be made using less material (e.g., the closure with ribs 30 may have thinner sidewalls and may weigh less) than a closure without impact resistant ribs while still providing acceptable impact resistant properties. Further, impact resistant ribs, such as ribs 30, may allow for the closures to be made from a material that has inherently lower impact resistant qualities than some other materials (e.g., impact resistant copolymers, etc.), while still providing acceptable impact resistant properties.
In various embodiments, the closures discussed herein may be of various sizes intended to seal containers of various sizes and having various contents. In some exemplary embodiments, the closures are configured to seal containers such as metal, glass or plastic containers or bottles for holding liquids. In specific embodiments, the closures may be 43 mm closures. In various embodiments, the ribs described herein, including ribs having the specific shapes, sizes, positioning etc., of the ribs 30 described herein, have been found to provide increased impact resistance when compared to some closures without such ribs or to closures having ribs of some other shapes, sizes, positioning, etc.
Further modifications and alternative embodiments of various aspects of the invention will be apparent to those skilled in the art in view of this description. Accordingly, this description is to be construed as illustrative only. The construction and arrangements of the closure, as shown in the various exemplary embodiments, are illustrative only. Although only a few embodiments have been described in detail in this disclosure, many modifications are possible (e.g., variations in sizes, dimensions, structures, shapes and proportions of the various elements, values of parameters, mounting arrangements, use of materials, colors, orientations, etc.) without materially departing from the novel teachings and advantages of the subject matter described herein. Some elements shown as integrally formed may be constructed of multiple parts or elements, the position of elements may be reversed or otherwise varied, and the nature or number of discrete elements or positions may be altered or varied. Other substitutions, modifications, changes and omissions may also be made in the design, operating conditions and arrangement of the various exemplary embodiments without departing from the scope of the present invention.

Claims

1. A closure, comprising:

a top panel;

a transition section extending downwardly from a peripheral edge of the top panel;

a skirt extending from a peripheral edge of the transition section such that the skirt extends away from the top panel; and

a plurality of raised ribs, each of the plurality of raised ribs including:

a first portion extending outwardly from an outer surface of the skirt and extending axially along at least a portion of the skirt, and

a second portion positioned above the first portion and extending outwardly from an outer surface of the transition section.

2. The closure of claim 1, wherein the transition section comprises a rounded shoulder having a curved outer surface.

3. The closure of claim 2, wherein the second portions of the plurality of raised ribs each include a rounded shoulder segment extending between the top panel and the first portion of each of the plurality of raised ribs.

4. The closure of claim 3, wherein an inner segment of the outer surface of the rounded shoulder of each of the plurality of raised ribs lies in the same plane as an outer surface of the top panel.

5. The closure of claim 3, wherein the second portion of each of the plurality of raised ribs does not extend axially above the peripheral edge of the top panel.

6. The closure of claim 1, wherein the plurality of raised ribs are each symmetric about a radial line extending through the center of each of the plurality of raised ribs.

7. The closure of claim 6, wherein the plurality of raised ribs include left and right sidewalls, the left and right sidewalls positioned at angles relative to the outer surfaces of the skirt and the transition section such that the left and right sidewalls converge, thereby defining outer edges of the plurality of raised ribs.

8. The closure of claim 7, wherein the outer edges of the plurality of raised ribs are rounded in the circumferential direction.

9. The closure of claim 1, wherein the skirt includes a downwardly and outwardly extending frustoconical portion positioned at the lower end of the skirt.

10. The closure of claim 9, wherein a lower section of each of the plurality of raised ribs extends in a radial direction along an outer surface of the frustoconical portion of the skirt.

11. An impact resistant closure, comprising:

a generally circular top wall;

a transition section extending from a peripheral edge of the top wall;

a generally cylindrical skirt extending from a peripheral edge of the transition section such that the skirt is substantially perpendicular to the top wall; and

a plurality of raised ribs, each of the plurality of raised ribs including:

a second portion positioned above the first portion and extending outwardly from an outer surface of the transition section,

wherein the second portions of the plurality of raised ribs are configured to deform upon impact to resist failure of the closure.

12. The closure of claim 11, wherein the transition section comprises a rounded shoulder having a curved outer surface.

13. The closure of claim 11, wherein the second portions of the plurality of raised ribs each include a rounded shoulder segment extending between the top wall and the first portion of each of the plurality of raised ribs.

14. The closure of claim 13, wherein an inner segment of the outer surface of the rounded shoulder of each of the plurality of raised ribs lies in the same plane as an outer surface of the top wall.

15. The closure of claim 14, wherein the closure is s sized to fit a container neck finish having an outer thread diameter of about 43 mm.

16. The closure of claim 13, wherein the plurality of raised ribs include first and second sidewalls, the sidewalls converging to define an outer edge of each of the plurality of raised ribs, and wherein the outer edges of the plurality of raised ribs are rounded in the circumferential direction.

17. A closure configured to be coupled to a container, comprising:

a top wall;

a rounded shoulder section extending from an outer edge of the top wall;

a skirt extending from an outer edge of the rounded shoulder section;

at least one thread extending from an inner surface of the skirt configured for engagement with threading located on a neck portion of the container;

a plurality of raised ribs, each of the plurality of raised ribs including:

a second portion positioned above the first portion and extending outwardly from an outer surface of the rounded shoulder section; and

a tamper evident band including a frangible connecting element coupling the tamper evident band to the skirt.

18. The closure of claim 17, wherein the closure is injection molded from a polypropylene homopolymer resin.

19. The closure of claim 17, wherein the closure is coupled to the container.

20. The closure of claim 17, wherein the second portions of the plurality of raised ribs each include a rounded shoulder segment extending between the top wall and the first portions of each of the plurality of raised ribs, and further wherein an inner segment of the rounded shoulder of each of the plurality of raised ribs lies in the same plane as an outer surface of the top wall.