Patent Application
20080073313
While the present invention is susceptible of embodiment in various forms, there is shown in the drawings, and will hereinafter be described, a presently preferred embodiment, with the understanding that the present disclosure is to be considered as an exemplification of the invention, and is not intended to limit the invention to the specific embodiment illustrated.
With reference to the drawings, therein is illustrated a molded plastic closure 10 embodying the principles of the present invention. As will be known by those skilled in the art, plastic closure 10 can be efficiently formed from polymeric materials, such as polypropylene or polyethylene, and can be formed by injection molding or compression molding. Notably, closure 10 can be configured to exhibit a relatively large diameter, such as on the order of 63 millimeter to 110 millimeters. However, a closure keeping with the principles disclosed herein can be otherwise sized.
To facilitate the desired closing of an associated container, closure 10 includes a circular, top wall portion 12, and an annular skirt portion 14 depending from the top wall portion. For some applications, closure 10 can be provided with a suitable, separate sealing liner element (not shown).
Skirt portion 14 includes a helical, internal thread formation 16, which is configured for engagement with a like, external thread formation on an associated container. By this arrangement, relative rotational movement of the closure with respect to the container effects application and removal.
In accordance with the present invention, skirt portion 14 is of a configuration which is desirably lightened, conserving plastic material, while exhibiting the requisite strength to facilitate efficient closure formation. To this end, the interior surface of skirt portion 14 defines an array of alternating, circumferentially spaced grooves 18, and associated lands, which together define a plurality of circumferentially spaced strengthening ribs 20 on the inside surface of the skirt portion. In accordance with the preferred form, strengthening ribs 20 are vertically oriented, and generally parallel to a vertical axis of the closure 10.
In accordance with a presently preferred form, each of grooves 18 has a circumferential dimension greater than a circumferential dimension of each of the associated lands separating adjacent ones of the grooves 18. Each of grooves 18 preferably has a generally semi-cylindrical configuration, with each of the grooves preferably being open at a lower, free edge of skirt portion 14.
The desired column strength of the closure 10 is further enhanced by the provision of a plurality of circumferentially spaced, gripping knurls 22 provided on an exterior surface of the skirt portion. As illustrated in
In the preferred form, the skirt portion 14 of closure 10 includes a relatively thick, annular bead portion 24 at a free edge of the skirt portion. Bead portion 24 defines a lower ejection surface against which force can be applied for effecting “stripping” of the molded closure 10 from an associated core pin during formation. As illustrated, exterior gripping knurls 22 preferably extend upwardly from annular bead portion 24.
From the foregoing, it will be apparent that numerous modifications and variations can be effected without departing from the true spirit and scope of the novel concept of the present invention. It is to be understood that no limitation with respect to the specific embodiment illustrated herein is intended or should be inferred. The disclosure is intended to cover, by the appended claims, all such modifications as fall within the scope of the claims.
