IE44386B1 - Tear-open bottle cap - Google Patents

Abstract

TEAR OPEN BOTTLE CAP A tear open bottle cap formed of lightweight sheet metal having a circular top panel surrounded by a cylindrical skirt connected thereto by a radiused juncture portion. An integrally formed pull member extends away from the skirt edge with score lines commencing at either side of the pull member and extending upwardly across the cap skirt. The score lines diverge outwardly away from each other within the radiused juncture portion and continue part way about the periphery of the cap top panel in arcuate paths. The terminal portions of the score lines extend outwardly into the cap skirt at spaced positions opposite the pull member. An annular sealing gasket is disposed within said cap top so as to lie just radially inwardly of the arcuate scoring.

Description

This invention relates to tear-off bottle caps formed from lightweight sheet metal and which are simply removed by hand. Heretofore beer, carbonated beverages and other liquids which were packaged in bottles and other small containers were frequently sealed by so-called crown caps. Such crown caps have the disadvantage of requiring an opener or other tool to remove them. In recent years the trend has been to replace the use of crown caps by caps which are easily handremovable thus avoiding the necessity of using an opener or other tool. One such type of hand-removable cap is formed with a tear strip which can be torn by a pulling action which enables the cap to be destroyed and removed by hand. This type of tear-off, hand-removable cap has met with considerable customer acceptance.

It has been found that the prior tear-off bottle caps are difficult to remove without spilling the contents of the bottle if the bottle is held in the user's hands while removing the cap. This is due to the fact that more pull is required to be applied as the tearing progresses across the top of the cap. Thus, when the bottle is held in one hand and the tearing of the cap is being done with the other hand the additional pull required to completely remove the cap is not applied evenly making it difficult to hold the bottle steady and resulting in spilling or splashing of the contents. - 2 44386 One way to alleviate this problem is to construct the cap so that the scored lines tear more easily. However, in constructing a tear strip with an improved ease of tearing many factors have to be taken into consideration. For example, the depth and configuration of the score lines will to a great extent be determined by the container pressure that the cap will be required to retain.

Another factor is the configuration of the scored or tear out area which is formed by the score lines. In this regard it has been found desirable for tht score lines, in the top panel of the cap, to have an arcuate configuration and to be positioned at the outer periphery of the top panel.

Heretofore, the common practice in the construction of tear-off handremovable caps has been to cover the score lines with an internal gasket. This has served to prevent the contents of the container or bottle from coming into contact with the scored area. In most cases the gasket is of a flowed-on type which adheres to the interior surface of the closure including the score line. Upon the removal of the cap it is not only necessary to tear the cap along the score lines but is also necessary to tear through the gasket material. Additionally, the use of high temperature gasket compounds such as are required for commonly employed sterilized food processing have a higher resistance to tearing which further aggravates the tearing problem.

According to the invention, there is provided a metal tear-off bottle cap for a container, comprising a circular top panel surrounded by a cylindrical skirt terminating in a lowermost free edge, a radiused juncture portion connecting said top panel and said skirt, a gripping ear formed as an integral part of said skirt extending from said free edge, a sealing gasket covering a portion of said cap interior, and a tearing zone commencing at the free edge of the skirt adjacent said gripping ear and extending upwardly across said skirt and blending into an arcuate path positioned within the radiused juncture of the cap and lying radially outwardly of said sealing gasket, said tearing zone extending rearwardly from said gripping ear to at least partially surround said cap top panel. Such a closure cap - 3 44386 ensures that tearing along said tearing zone causes the major portion of said cap top panel to be separated from said cap skirt without also having to tear the gasket, so that the removal force necessary to sever the thin layer of metal remaining behind the score line in order to remove the cap of this invention from a bottle is minimal. In addition, the particular scoring pattern offers the advantage of allow’ng the major part of the cap top pane! to be lifted inwardly off o: the underlying bottle mouth or fir.ish as the cap is being torn open, leaving only a very narrow surrounding portion of the cap skirt for easy dislodgement from the bottle as the termination of the tearing action is reached.

An embodiment of the invention will now be described by way of example and with reference to the accompanying drawings, in which:Figure 1 is a perspective view of a closure cap in accordance with the invention; Figure 2 is a top plan view thereof; Figure 3 is a sectional view taken along the line A - A in Figure 2 and looking in the direction of the arrows; Figure 4 is an enlarged fragmentary sectional view showing the juxtaposed relationship between the sealing gasket and the semi-circular scoring, and Figure 5 is a perspective view of the closure in its torn-open position just prior to separation from a bottle.

The closure cap of the invention, generally indicated by numeral 1 and, as shown in Figures 1 and 2, is formed out of a lightweight sheet metal and comprises a circular top panel 2 surrounded by a radiused juncture portion 3. A cylindrical skirt 4 depends from the juncture portion 3 and terminates in a lowermost free edge 5. A major annular region 6 is formed in the top panel 2 and radially outwardly blends into the radiused juncture portion 3 in a gradually upwardly inclined outer step portion 7 thus forming a shallow inverted channel 8 as clearly seen in Figure 4.

In addition, a circular panel 9 is centrally disposed within the major annular region 6, defined by an inclined inner step 10, The closure cap 1 is further provided with a gripping ear 11 extending downwardly from the skirt free edge 5 in a short neck 12 and then extending radially outwardly and downwardly in a base portion 13 which merges into a pull ring 14. A pair of parallel, embossed reinforcing ribs 15 extend vertically from the base portion 13 across the neck 12 and skirt 4 and terminate at the radiused juncture portion 3.

A pair of score lines generally indicated at 18 are formed in the cap body and, for illustration purposes, are shown as being formed in the exterior surface of the cap, although interior scoring could also be employed. Each of the score lines commences at a notch 17 formed in the skirt edge 5 at either side of the neck portion 12. From the notches 17 the scores 18 extend upwardly across the cap skirt 4. Upon entering the radiused juncture portion 3, the score lines flare outwardly away from each other at 19 and blend into arcuate paths 20 extending part way about the radiused juncture portion 3 surrounding the periphery of the cap top panel 2. The curved score line portions 20 are so positioned within the radiused juncture portion 3 as to define the outer border of the inverted channel 8. Each score line portion 20 continues along an arcuate path to a point angularly displaced approximately 45 degrees from a point diametrically opposite the gripping ear 11 and then flares radially outwardly at 21 terminating in the cap skirt 4 on the opposite side of the cap from the gripping ear 11.

An annular sealing gasket 22, consisting, for example, of a vinyl resin plastisol, is formed, for example by deposition, within the cap interior. As clearly seen in Figure 4, the gasket 22 completely occupies the shallow inverted channel 8 created by the inclined top panel outer step 7 and the part of the radiused juncture portion 3 disposed above the score line portion 20. This gasket configuration leaves the score line 20 exposed just beyond the outer edge of the gasket with the inner edge of the gasket flowing radially inwardly from the channel 8 towards the annular region 6 to form an effective top seal when applied to a container. This arrangement of placing the score line completely outside the gasket offers the advantage of protecting the score line area against exposure to the packaged product without resort to costly post-coating operations. Such - 5 44386 protection is frequently required where lack of product compatibility may cause a chemical attack on the closure cap base metal with resultant contamination of the packaged product. Even with scoring on the outside surface of the cap, a certain amount of damage occurs to the interior surface coatings which must still be protected against.

A bottle 23 provided with a circumferentially enlarged lip 24 surrounding the bottle neck opning vr finish is shown in Figure 5. The closure cap 1 of the invention is here shown in an intermediate opening position with the cap in the torn-open condition but prior to complete separation from the underlying bottle lip 24.

In addition to the already described advantages resulting from the improved score pattern of the present invention, opening and removal of the cap is similarly enhanced. A substantial amount of tearing resistance has heretofore been encountered as the sealing gasket 22 is severed in tearing across and along it during tearing of the cap from the underlying bottle neck. As is clearly evident from the above described’gasket-score line relationship of the invention, any tearing through the relatively tough gasketing material has been completely avoided. The only tearing force required to uncap the bottle is that necessary to sever the very thin section of remaining metal behind the score lines.

Finally, the score line configuration of this invention has been found to make a significant improvement in the ease with which the torn open cap is separated from the bottle. This ease of cap removal conies about by reducing to a minimum the ability of the remaining cap portions to grip the underlying bottle lip 24. With the score pattern herein disclosed, only a narrow band of metal consisting of the skirt portion 4 and the remaining part of the radiused juncture portion s is left in engagement with the bottle lip after tearing. Completion of the tearing action occurs when the metal becomes severed along the full extent of the score lines 20 and the terminal points remote from the gripping ear are reached. Continuation of the normal pulling force applied to the ring 11 then causes the - 6 44386 relatively flimsy remaining cap portion to be quite easily dislodged from the underlying bottle lip 24 thus avoiding any undesirable splashing or spillage of the bottled product.

From the foregoing it is readily apparent that numerous advantages result from the closure cap of the invention as above described. It should be noted that variations in the cap construction could be employed such as varying the construction or shape of the cap gripping ear. Also different gasketing systems could be employed such as an overall liner adhered to or frictionally retained within the cap interior.

The tear-off bottle cap disclosed provides a cap construction which completely eliminates the need to tear through the cap gasket when the cap is torn. This is accomplished by using score lines which have arcuate configuration and which are positioned in the radiused juncture portion of the cap rather than in any portion of the cap top panel. An annular sealing gasket is secured to the interior surface of the cap top panel and is positioned radially inwardly of the arcuate score lines. Since the score lines are positioned outside the gasket area this construction has the technical effect of requiring only the metal score area to be torn for removal of the cap. This eliminates the problem of having to tear the gasket itself in addition to the metal remaining in the scored areas.

This is of particular significance because in providing a cap having score lines with improved tearing qualities, the problem of the previously known caps is eliminated in which the tearing became progressively more difficult as it proceeded, required the application of more tearing force which in turn resulted in agitation and spilling of the bottle contents. An additional technical effect is achieved in that the scored area is protected by the gasket from contamination by the bottle contents (and vice versa) without having the gasket positioned directly over the score lines. Additionally the gasket serves to cushion against the effect of pressure within the container acting against the scored areas which could cause a premature rupturing thereof.

Claims (6)

C L AIMS

1. A metal tear-off cap for a container, comprising a circular top panel surrounded by a cylindrical skirt terminating in a lowermost free edge, a radiused juncture portion connecting said top panel and said skirt, a gripping 5 ear formed as an integral part of said skirt extending from said free edge, a sealing gasket covering a portion of said c?p interior, and a tearing zone commencing at the free edge o' the ;kirt adjacent said gripping ear and extending upwardly across said skirt into said radiused juncture portion and blending into an arcuate path positioneo within the radiused juncture portion of said cap and 10 lying radially outwardly of said sealing gasket, said tearing zone extending from said gripping ear to at least partially surround said cap top panel.

2. A tear-off cap according to Claim 1 including a tearing zone commencing at said skirt free edge on either side of said gripping ear.

3. A tear-off cap according to Claim 1 or Claim 2, wherein said sealing 15 gasket extends radially outwardly to a position in close proximity to said arcuate tearing zone path.

4. · A tear-off cap according to any one of Claims 1 to 3, including a concentric annular region formed in said cap top panel.

5. A tear-off cap according to Claim 4, wherein a gasket receiving channel 20 is formed by said annular region about the periphery of said cap top panel.

6. A metal tqar-off cap substantially as hereinbefore described and with reference to the accompanying drawings.