US3421653A - Container closure - Google Patents

Description

Jan. 14, 1969 R. E. WHALEY 3,421,653

CONTAINER CLOSUR E Filed April l1. 1967 Jv v Y v l y I United States Patent O 2 Claims ABSTRACT F THE DISCLOSURE A one-piece, snap-on container closure of the type adapted for use with an open top container. The closure which is preferably formed of a lexible thermoplastic material is provided with a peripheral shoulder adapted to overlie the bead of the cooperating container, a downwardly depending skirt on the outer edge of the shoulder adapted to engage the outside of the cooperating container, and a depressed center panel. At the inner edge of the shoulder adjacent the depressed center panel there is provided a continuous integral upwardly and inwardly extending flange providing a restricted opening to the depressed center panel and adapted to mechanically retain in the region adjacent the depressed center panel a separate planar insert having substantially the dimensions of the depressed center panel and preferably formed of paper board.

BACKGROUND OF THE INVENTION Field of the invention This invention relates to a one-piece, snap-on container closure formed preferably by molding from a iiexible thermoplastic material such as low density polyethylene. The closure is of the type adapted to receive an insert on its upper surface, such as a printed paper board insert and for this purpose is provided with a depressed center panel to receive the insert and with an integral continuous rupwardly and inwardly extending flange surrounding the depressed center panel to retain the insert.

Description of the prior art Open top containers have become popular for a variety of purposes including particularly frozen products, such as ice cream, and the like. These containers are provided with snap-on closures which can be removed easily to gain access to the contents of the container. Such containers have ibecome popular in the marketplace because of the reuse value to the consumer. Once the original contents have been removed from the container the consumer can and does reuse the container for a variety of purposes, such as, for example, for storing leftovers.

Experience has shown that the consumer places considerable value in this reuseability feature and will, where -he or she has the choice, choose between two competing products of equal quality at an equal price on the basis that Ione such product is packed in a container capable of being conveniently reused, and the other is not. But even among reuseable containers the preference of the consumer quite decidedly is toward one lwhere the original product brand identification can readily be removed before such reuse over one where such removal is either difficult or impossible. Thus a container where the product and Ibrand Iidentification is provided solely on a removable paperboard insert will be selected over one where this product and brand identification is either printed -on or provided by means of a label adhesively secured to the container.

The problem then is to provide a means associated with the container which permits the easy insertion of an insert of paperboard or the like, which insures that the insert ICC will remain securely in place during all phases of packaging, distribution and sale, and even during the period yof initial use by the consumer, and yet will permit the insert to be removed easily iby the consumer after the period of initial use and before reuse.

-One suggestion for such means is disclosed in Crisci U.S. Patent 3,176,868. This patent discloses a closure or cover which has a flat horizontal body portion above which projects a concentric ring or ange having a plurality of inwardly directed protrusions spaced above said body portion so as to form a space for the insertion of an insert. The insert if formed from a relatively inexible material, such as paperboard, and-if properly sized so that its outer edge lies immediately against the inner edge of the upstanding ring, will be held in place by the inwardly directed protrusions. The problem with the closure disclosed in Crisci U.S. Patent 3,176,868 comes from the fact that paperboard from which the insert is normally made, and the thermoplastic material, such as polystyrene or polyethylene from which the oover is made, have drastically different temperature coeilicients of expansion. When the temperature of the combination is reduced from room temperature to the below freezing, or even below 0 F. temperature used for the storage of frozen foods, the paperboard insert either retains the same size or even expands in diameter depending on the moisture content of the paperboard while the plastic cover shrinks considerably in size. Thus if the insert is sized to cooperate with the retaining ring on the closure at the temperatures used for the storage of frozen products, the insert will be so loose as to fall out of the cover at orr near room temperature. Conversely if the insert is sized to cooperate with the retaining ring on the cover at room temperature the insert will either distort the retaining ring and knock oit the inwardly directed protrusions, or will itself be distorted out of shape depending on the relative strength of the elements when the container is chilled to the temperatures employed in the storage of frozen products. Under any of these circumstances there is a real danger that the insert will become separated from t-he parkage during storage or handling leaving the package unmarked and hence unidentiable. Even when this does not happen the insert becomes distorted out of shape making the package esthetically displeasing and hence relatively unsaleable, especially in the retail market.

SUMMARY OF THE INVENTION It is the object of this invention to provide means in a one piece snap-on container closure for retaining a paperboard insert thereon throughout the entire range of temperatures to which the closure may be subjected without any reasonable possibility that the insert can Ibecome separated from the closure under normal conditions of handling, while at the same time permitting the easy insertion and the easy intended removal of the insert while the closure is at room temperature. Specifically these means include providing the closure with a depressed center panel and providing an upwardly and inwardly extending oontinuous integral ange on the inner edge of the shoulder of the closure surrounding the depressed center panel and extending thereover. These and other objects of this invention will better Ibe understood from the drawings and from the detailed description which follows.

BRIEF DESCRIPTION OF THE DRAWING In the drawing:

FIG. 1 is an elevation of the container closure of the present invention.

FIG. 2 is an enlarged elevation in section of the marginal portion of the closure particularly within the area 2 of FIG. 1.

3 DESCRIPTION OF THE PREFERRED EMBODIMENT The one-piece, snap-on closure of the present invention indicated generally at comprises a depressed center panel 11 and a shoulder portion 12. In common with all closures of this type a downwardly dependin-g integral skirt 13 is provided `at the outer edge of shoulder 12 'and is adapted to engage and cooperate with the outside of the wall of a cooperating container. The inner side of skirt 13 is provided With a -conventional inwardly extended beaded portion 14 near the bottom thereof. In common with all such closures the shoulder portion 12 is designed to extend over the top of the side wall of the cooperating container with the depressed center panel 11 located within the walls of the container. It will be understood, of course, that while the drawing shows, and this description may make reference particularly to a circular closure designed to cooperate with a generally cylindrical container, the particular shape of the container or of the closure has no bearing on the invention, and the closure of the present invention could equally well be formed to any desired overall shape, such as, for example, oval or generally rectilinear to cooperate with a container having a cross-section of that shape.

Referring then particularly to FIG. 2 where the elements of the present invention are shown in magnified detail, the top of shoulder 12 is provided with a stacking ring 15, -an upstanding flange a'bout 1/16 of an inch in height located at a position to engage lbead 14 of skirt 13 of the next higher closure 10 in a stack of closures 10. The function of stacking ring 15 is to maintain the alignment of the closures 10 in a stack of closures and to separate successive closures slightly so that the Ibottommost closure in a stack of closures can readily be separated from the remainder of the stack in automatic closure applying machinery.

Center panel 11 is depressed in practice about 1/8 of an inch below the level of shoulder 12 and the outer edge of depressed center panel 11 is connected to the inner edge of shoulder 12 by means of vertical side wall 16. Continuous integral upwardly `and inwardly extending fiange 17 is provided on the top surface of shoulder 12 immediately adjacent vertical side wall 16 in the sense that the inner edge of flange 17 is an extension of the inner edge of side wall 16. In the particular embodiment shown flange 17 extends 'about 1A; of an inch above the top surface of shoulder 12 and into the space overlying depressed center panel 11 a distance of about z of an inch. In other words, the innermost corner of fiange 17 is located at a point a little less than 1A; of an inch above the top of shoulder 12 and about '5){52 of an inch inside of (i.e., away from skirt 13) the vertical projection of the inner edge of vertical side wall 16.

The purpose of inwardly and upwardly extending fiange 17 is to provide an entrance of restricted size into the region above depressed center panel 11 for inserts such as the insert indicated at 18. Thus in the particular embodiment shown the diameter of the entrance to the region above depressed `Center panel 11 formed 'by inwardly and upwardly extending ange 17 is approximately 3/16 of an inch less than the diameter of center panel 11 as determined by the inner edge of vertical side wall 16. The particular closure illustrated in the specific embodiment is a closure designed for a tone-pint jar land has an overall diameter of 4%". In this particular closure the diameter of the opening to the region above center panel 11 as defined by the inner corner of fiange 17 is 4" and the cardboard insert 18 has a diameter of 41/16". Since the cardboard insert 18 has only a slightly larger diameter than the diameter of the opening defined by the inner corner of flange 17 insert 18 will snap into and out of the space above center panel 11 very easily. However, since flange 17 is continuous (i.e., uninterrupted) even this slight difference in diameters makes it impossible for insert 18 once inserted to pop out no matter how roughly closure 10 is handled. Since the only way that insert 18 can readily be removed is by manipulating its edge as with a knife, a small cutout portion is, in practice, provided at one point on its edge to permit removal by manipulation with `a finger. The diameter of center panel 11 as defined by the inner edge of cylindrical side wall 16 is sufiiciently larger than the diameter of insert 18 at room temperature that due to the differential contraction when chilled, as explained above, the edge of insert 18 comes into firm contact with side wall 16 at the temperature employed in the storage of frozen products. Under this condition it becomes virtually impossible to remove insert 18 even intentionally, so that there is virtually no possibility that the identifying insert, when used in a container for frozen products, could be separated from the closure either intentionally or otherwise.

It will be understood, of course, that the particular dimensions given here are merely by way of illustration. The desired condition is to provide a degree of undercut beneath inwardly extending fiange 17 sufficient to accommodate insert 18 at the coldest temperature to which the closure is expected to be exposed to with the opening formed by flange 17 being smaller than insert 18 even at the highest temperature to which closure 1t) is expected to be exposed. Obviously, therefore, the necessary degree of undercut is increased as the dimensions of closure 10 and of insert 18 are increased, or as the expected range of temperatures is increased, while a lesser degree of undercut would be satisfactory for a smaller closure or insert or for a more restricted range of temperatures.

`Closure 10 is preferably formed of a somewhat flexible thermoplastic material such as, for example, low density polyethylene. The preferred method of making closure 10 is through a normal injection molding process. It has been found that the particular specific configuration shown herein can be made of low density polyethylene in a simple two part mold without any difficulty in stripping the formed closure 10 from the mold. The particular angle at which flange 17 departs from the upper surface of shoulder 12 is of no particular importance since the function of flange 17 is primarily to provide a restricted opening into the region immediately above center panel 11. It has been found, however, that if flange 17 extends somewhat upwardly, as well as inwardly, closure 10 can `be removed from a simple ymold readily, whereas it would be anticipated that if fiange 17 extended horizontally or downwardly a more complex mold would be required.

I claim:

1. In a one-piece, snap-on container closure formed from a flexible thermoplastic material and adapted for use with an open top container,

a peripheral shoulder adapted to overlie the bead of a cooperating container,

a downwardly depending skirt on the outer edge of said shoulder,

said skirt having an inwardly extending beaded portion near the bottom thereof,

said skirt and said beaded portion adapted to engage and cooperate with the outside of the wall of said cooperating container,

an upstanding fiange located on said shoulder at a position to engage the beaded portion of the skirt of the next higher closure in a stack of said closures to maintain the alignment of said closures in said stack of closures,

a downwardly depending sidewall portion at the inner edge of said shoulder at a position Within the body portion of said cooperating container,

a depressed center panel extending generally parallel to said shoulder from said side wall portion across said closure,

and an integral upwardly and inwardly extending fiange at the intersection of said shoulder and said downwardly depending side wall portion,

said flange providing a restricted opening to said de- 5 6 pressed center panel and adapted to mechanically References Cited retain in the region adjacent said depressed center UNITED STATES PATENTS panel Within said side wall portion a separate planar 2. In combination an open top container, the one-piece, snap-on closure as claimed in claim 1 and a planar insert in the region adjacent the depressed center panel of said closure.

JAMES B. MARBERT, Primary Examiner.

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