Threaded Bottle Cap With Vertical External Scores

Abstract

A threaded bottle cap with a pilfer-proof skirt externally vertically scored and of sufficient length to be locked under a shoulder on the neck of a container to provide rounded, relatively smooth edges when the scores are ruptured as the cap is removed from the container.

Parent Case Text

This is a continuation-in-part of my copending application Ser. No. 117,512 filed Feb. 22, 1971, now abandoned.

Description

BACKGROUND OF THE INVENTION

1. Field of the Invention

This invention relates to a cap, or closure, attached to the open end of a container by threaded engagement with the neck of the container and having a pilfer-proof skirt turned under a locking shoulder below the threaded portion on the neck of the container. In particular, the invention relates to a closure of this type having external vertical scores in the skirt.

2. Description of the Prior Art

Threaded bottle closures with pilfer-proof skirts have become quite common in the past few years for use on containers of beverages and other liquids that used to be sold in containers capped by means of crowns. A crown, once removed, cannot be easily replaced on a container since the removal normally involves visibly deforming the crown. However, it is possible for a closure that makes threaded engagement with the neck of the container to be removed by unscrewing it and then replaced without indication that the container has been opened. It is desirable for the consumer to be able to do this but undesirable for it to be done prior to reaching the consumer, especially in the case of containers used to dispense beverages because of the possibility of contamination of the product. It would even be undesirable in the case of products not intended for human consumption because it would also make such products subject to possible contamination or pilferage.

In order to lock a threaded, metal closure in place, it has become common in recent years to provide, at the lower edge of the cylindrical part of the closure, a skirt to be deformed by a roller during the capping process so as to turn the skirt under the locking shoulder normally provided on such containers. This skirt is referred to as a pilfer-proof skirt and is initially formed as an integral part of the closure. These closures are made of ductile sheet metal, such as aluminum. During the manufacture, the cylindrical part of the closure is lanced by blades perpendicular to the axis of the closure and spaced a slight distance apart to leave several spaced bridges, which are relatively narrow sections of the ductile material. The lancing weakens the skirt so that when the closure is unscrewed the bridges are forced to rupture, thus allowing the pilfer-proof section to remain upon the neck of the container when the main part of the closure is removed. The main part can later be reapplied to the container, but it will be evident to anyone who later picks up the container that it has already been opened. Thus any potential consumer will be aware that there is a possibility of contamination or pilferage of the product.

Such containers have been almost invariably of the type to be used only once and are frequently referred to as "no return" bottles. One reason for this type of use is that the pilfer-proof ring is somewhat difficult to remove from the container and it is easier to sell the container for only a single use. In the case of beer and other alcoholic beverages sold in such containers, there is the added legal requirement that they not be used a second time. However, with the advent of widespread public interest in environmental protection, it has been found to be advantageous to make the pilfer-proof section easily removable from the neck of the container so that the container can be used again if it is legally permissible to do so. In addition, the lancing leaves a relatively sharp edge on the main part of the closure, and the small sections of the ridges increase the possibility that a person attempting to remove or replace such a closure may be cut. Moreover, it is not uncommon for some of the bridges to fail to break when an attempt is made to unscrew the closure. When this happens the threaded part of the closure is twisted askew on the threads of the container and thus becomes locked in place. Under such circumstances, it may be almost impossible to remove the closure without the aid of a suitable tool. In my U.S. Pat. No. 3,645,062 I proposed to make the closures easier to break by scoring across the bridges in a direction perpendicular to the axis of the container and in line with the long dimension of the lanced slots.

The present invention is directed to a different scoring technique that permits the pilfer-proof section to be bent out of the way easily so that the entire cap, including this section, can be removed from the neck of the container without causing the threads on the closure to become twisted askew with respect to the threads on the container. The bending of the pilfer-proof section that results from unscrewing such a closure from the container on which it is placed is sufficient evidence that the closure has been tampered with, but it may be desirable, in addition, to provide a visible pattern, such as a series of horizontal lines, on the pilfer-proof section to indicate that the scoring marks have been broken through by removing the closure from the neck of the container.

One type of closure that has been proposed as a means of attaching the pilfer-proof skirt to the main part of the closure is described in U.S. Pat. No. 3,601,273. In that patent, the lancing is done in such a way that alternate bridges are relatively wide and the remaining bridges are relatively narrow. The pilfer-proof skirt is vertically scored from the inside with fewer scores than the number of bridges and with no attempt to align the scores in any particular position relative to the bridges. When such a closure is removed from the neck of a container, it is expected that the vertical scores will rupture allowing the sectors of the pilfer-proof skirt to be cammed outwardly by the shoulder of the container. However, as shown in FIG. 4 of that patent, an extremely dangerous rupture of certain of the bridges may take place causing sharp pointed sections of the pilfer-proof skirt to project outwardly to a position where anyone attempting either to loosen or tighten the closure may be severely cut. The pilfer-proof skirt is most likely to break out this way when the scores happen to be aligned with the narrow bridges. The dangers of such a structure are readily apparent to consumers. In addition, there is a growing tendency for agencies of the government having to do with product safety to become concerned about items such as this.

It is one of the objects of the present invention to provide a closure member having a pilfer-proof section that can be easily separated into relatively small sectors having no sharp edges and attached to the remainder of the closure in such a way as to be easily bent back far enough to allow the closure to be easily removed from the container and reapplied thereto in case the product in the container has been only partially consumed.

A further difficulty encountered with some attempts at providing a screw-type closure with a pilfer-proof section that is removed from the container with the rest of the closure is the tendency of some of the scores to remain closed, thereby providing an unbalanced resistance to removal of the closure. This may cause the threaded part of the closure to be shifted askew, which greatly increases the torque required to remove the closure from the container. This is similar to the case of closures having unscored pilfer-proof rings attached by bridges that fail to break.

It is, therefore, a further object of the present invention to provide a screw-type closure with a pilfer-proof section that remains attached to the main part of the closure and has scores so arranged that the pilfer-proof section is uniformly divided into the desired individual sectors, thereby permitting easy removal of the closure from the container and easy replacement of the closure on the container.

BRIEF DESCRIPTION OF THE INVENTION

The bottle cap in accordance with the present invention includes bridges that are wider than the normal bridges in closures used heretofore. The metal of the pilfer-proof section below the bridges is scored externally and in a direction parallel to the axis of the container and in a region specifically related to the location of the bridges. When such closures are removed, the pilfer-proof section breaks through at the scored locations and twists the relatively narrow metal of the bridges to allow the pilfer-proof section to ride up over the threaded part as the closure is removed from the neck of the container. I have even found it possible, although less desirable, to omit the lateral slots that are lanced through between the threaded portion and the pilfer-proof skirt of the closure. As another alternative, I have found that the pilfer-proof section may be scored directly below each of the lateral slots instead of directly in line with the center of each of the bridges.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a side view of a closure scored in accordance with the present invention and fitted on the neck of a bottle.

FIG. 2 is a cross-sectional view along the line 2--2 of the bottle and closure in FIG. 1.

FIG. 3 shows a modified scoring arrangement for a second embodiment of a closure in accordance with the present invention.

FIG. 4 shows still another embodiment of the present invention.

FIG. 5 is a developed view of the lower edge of a closure scored in accordance with still another modification of the invention.

FIG. 6 is a side elevational view of the closure in FIG. 1 prior to the time it is applied to a container and has threads formed in it.

FIG. 7 is a perspective view of a lancing and scoring tool for use in the manufacture of the closure in FIG. 6.

FIG. 8 is a plan view of a lancing and scoring blade for use in the tool in FIG. 7.

FIG. 9 is a cross-sectional view of the lancing and scoring tool in FIGS. 7 and 8 at one point of contact with a closure.

FIG. 10 is a fragmentary cross-sectional view corresponding to FIG. 9 but illustrating a different point of contact between the closure and the scoring blade.

FIG. 11 is a simplified top elevational view of a machine for knurling, scoring and lancing the closure of FIG. 6.

FIG. 12 is a fragmentary cross-sectional view of the closure in FIG. 1 illustrating the clearance between the closure and the container onto which it is threaded.

FIG. 13 is a fragmentary view of the pilfer-proof section of the closure in FIG. 1.

FIG. 14 is a fragmentary view corresponding to FIG. 13 but illustrating the way that the score ruptures when the closure is removed from the container.

FIG. 15 is a bottom view of the closure according to the present invention illustrating the deflection of the pifler-proof section caused by removal of the closure from a container.

DETAILED DESCRIPTION OF THE INVENTION

FIG. 1 shows a bottle closure 11 having a flat top 12 and a generally cylindrical skirt extending downwardly from the perimeter of the top. This closure is preferably made of ductile material, such as a deformable aluminum base alloy having a thickness of about 0.010 to 0.011 inch. At the upper end of the skirt is a knurled band 13 that provides better frictional engagement with the closure so that the latter can be more easily unscrewed from a container 14. Below the knurled band 13 the skirt has been deformed into a threaded section 16 and at the lower end of the threaded section is an outwardly extending bulge 17 formed by pressing the sheet metal material of the skirt outwardly by a predetermined amount. The extent of the outward bulge will be described in greater detail hereinafter. The bulge may include, at its upper side, a second knurled band 18. Between the upper and lower limits of the bulge 17 are several lateral slots 19, each formed by lancing a short tongue of the skirt material inwardly, preferably pivoting each of the tongues about the lower edge thereof. The section of the skirt that remains between the slots 19 are bridges 21 that join the upper part of the closure 11 to a pilfer-proof section 22 that forms the lowermost part of the skirt.

In accordance with this invention, a plurality of vertical scores 23 are formed in the pilfer-proof section 22, and in this embodiment each of the scores 23 is directly in line with and below the center of each of the bridges 21. The lowermost end of the skirt is tucked under a shoulder (not shown) on the neck of the container 14, and, if desired, a plurality of stripes 24 may be printed on the pilfer-proof section to assist in visually indicating when the scores 23 have been broken in removing the closure from the container.

As will be described in greater detail hereinafter, when the closure 11 is unscrewed from the container 14, each of the scores 23 ruptures so that the pilfer-proof section breaks into small sectors. Each of the bridges 21 forms a hinge for the ends of the pilfer-proof sectors 22 below that bridge.

FIG. 2 shows a cross-sectional view to illustrate the arrangement of the bridges 21 and indicate that there are eight of such bridges. It is possible to use other numbers of bridges, but I have found that the use of eight bridges allows the closure to be removed without having to deform the pilfer-proof section as much as would be necessary if there were a smaller number of bridges. At the same time, it is easier to provide eight bridges than to try to fit nine or more around the closure 11.

FIG. 3 shows a modified closure 26 in which each of the external scores 27 has been extended up through the respective bridge 21 with which it is aligned. This would appear to increase the flexibility of the hinges formed by the two sections of each bridge on each side of the respective scores 27, but under certain circumstances it may be desirable not to increase the flexibility to this extent. Further, this embodiment is not as amenable to having a bulge 17 since the scores would have to extend into the bulge and would be difficult to produce.

FIG. 4 shows still another form of closure 28 in which there are scores 29 of approximately the same length as the scores 23 in the embodiment in FIG. 1, but there are no transverse slots and, therefore, no bridges to be aligned with these scores. Since the closure in any of the foregoing embodiments comes off of the container as a unitary structure and does not leave a pilfer-proof ring behind as in the case of closures previously used, it would appear that the slots that result in forming the bridges 21 of the embodiments of FIGS. 1-3 are not necessary, and, indeed, it has been found possible to do without them as is shown in the embodiment in FIG. 4. However, this means that the entire length of metal from one of the scores 29 to the next forms a hinge, whereas in the embodiments in FIGS. 1-3 only the thin strips of metal of the bridges 21 form the hinges. The segments of the pilfer-proof section 22 in FIG. 43 are stiffer and make it more difficult to remove the closure 28 from the container 14. If this is desirable, then the slots can be omitted as in the case of this embodiment. Furthermore, the external scores 29 may be increased somewhat in depth to make it easier for them to be ruptured when the closure is removed from the container.

FIG. 5 shows a fragmentary side view of still another modification of the invention with the scores 31 midway between the bridges 21 instead of in line with them. The bridges 21 are formed when tongues 32 are lanced out of the closure material and pressed inwardly to form the slots 19. Each of the scores 31 extends from the lowermost edge of the pilfer-proof section 22 to a point just below the lowermost edge of the respective tongue 32. In this case, the stiffness of the pilfer-proof section 22 that resists bending when the cap is removed from the bottle is less than that in the embodiment of FIG. 4 but greater than that in the embodiment of FIG. 1.

FIG. 6 shows the closure 11 of FIG. 1 prior to the time it is placed on a container. Thus, the threads 16 of FIG. 1, which are formed during the process of sealing the container, have not yet been incorporated. However, the knurled band 13 and, particularly, the bulge 17, the knurled band 18, the slots 19, and the bridges 21 are shown somewhat more clearly in FIG. 6 than in FIG. 1. The slots 19 are formed in such a way that the metal is bent inwardly from the top edge of the slots rather than from the bottom as in FIG. 1. In addition, the pilfer-proof section 22 is shown as being slightly conical with an included angle of approximately 6.degree. to facilitate placing the closure on a container to be sealed. The scores 23 have also been formed by the time the closure 11 reaches the stage of manufacture shown in FIG. 6.

FIG. 7 shows a device 33 constructed to lance and score caps in accordance with the present invention. The device 33 is mounted on a shaft 34 and comprises a plurality of lancing blades 36 that form the slots 19 in FIG. 1. Simultaneously, with the lancing the device 33 scores the vertical marks by means of vertical scoring blades 37. Since these scoring blades are fixedly positioned with respect to the lancing blades 36, the location of the scores relative to the bridges 21 in the closure 11 in FIG. 1 is fixed. This device 33 can be used to provide the scores 21 and the slots 19 as shown in the closure 11 in FIG. 1. If the scoring blades 37 are made longer so that they extend up between the lancing blades 36, the device 33 may also be used to lance and score the closure 26 shown in FIG. 3. By omitting the lancing blades 36, the device 33 may be used to form the scores 29 in the closure 28 of FIG. 4.

The lancing and scoring blades and the mechanism are shown in more detail in FIGS. 8-10. FIG. 8 shows one form of the lancing and scoring blade adapted for use in certain capping machines. Only about half of the perimeter of the lancing blade 38 is provided with lancing edges 39. For the sake of convenience, the structure shown in FIG. 8 is actually made up as a tool pack and individual scoring blades 41 are fitted in slots centered between pairs of the lancing edges 39. The tool pack is formed as an annular structure with a central aperture 42 to fit on a support in a capping machine. The tool pack also is provided with apertures 40 that allow the tool pack to be assembled with a specific relationship between the lancing edges 39 and the scoring blades 41.

FIG. 9 shows a closure 43 supported on a rotating member 44 in a forming machine. The member 44 has a knurling ring 46, a cylindrical section 47, a pair of discs 48 and 49 that produce the outward bulge 17 in the closure 43 and also cooperate to produce the knurled band 18 and the slots 19. Below the disc 49 is a tapered section which may comprise two discs 51 and 52 to form the slightly conically tapered pilfer-proof section 22 of the closure 43. Below the disc 52 is a limit ring 53 that prevents the closure material from being squeezed too much while the closure 43 is being formed.

Cooperating with the member 44 to form the closure 43 is a group of discs, including a knurling ring 54 that cooperates with the ring 46 to form the upper knurled band 13. Below the ring 54 is another cylindrical ring 56, the lower side of which is machined away to cooperate with the disc 48 in forming the bulge 17 and the knurled band 18. Below this is the lancing blade 38, one of the edges 39 of which is shown pressing a tongue 32 into the bulge 17. Below the lancing blade 38 is a section that holds the scoring blades 37 and below that is a disc 57 that presses against the ring 53 when the closure 43 is being formed. As shown, each of the scoring blades is at an angle that corresponds to the taper in the disc 52.

FIG. 10 shows a different cross-sectional view of the closure forming apparatus and particularly illustrates the way that one of the scoring blades 37 presses into the pilfer-proof section 22 of the skirt of the closure 43. The blade 37 may be set so that it presses approximately 0.006 inch into the 0.010 inch thickness of the closure metal.

Another type of closure forming machine is shown in FIG. 11. In this machine, unformed closures 58 enter the machine along the direction of the arrow 59 up a ramp 61. Each of the closures 58 has its open end facing upwardly and it is picked up by an arbor 62, which may be generally similar to the member 44 in FIG. 9. This arbor 62 rotates as shown by the arrows 63 and moves in a circle as indicated by the arrow 64 to push the closure 58 along a circular shelf 66. A raised central disc 67 has several forming stations set into it. The first of these stations is indicated by reference numeral 68 and forms one of knurling bands, for example the knurling 13 shown in the closure in FIG. 9. In order to form this knurling band, the arbor 62 revolves the closure 58 against the knurling surface of the station 68. Subsequently, the closure 58 reaches a second station 69, which has a configuration suitable for forming the bulge 17 and the second knurling band 18 as shown in FIG. 9. Thereafter, the closure 58 is brought around to the third station, which includes a lancing blade 71 with lancing edges 72. Scoring blades 73 are fixedly located with respect to the lancing edges 72 to place the scores as desired and preferably centered with respect to the bridges formed by the gaps between adjacent scoring edges 72. Thereafter, the closure 58, which is then in the same configuration as the closure 11 in FIG. 6, leaves the shelf 66 by way of a downwardly sloping ramp 74.

FIG. 12 is a fragmentary cross-sectional view showing the closure 11 of FIG. 1 applied to a glass bottle 14. As may be seen, the bottle has a shoulder 76 and the pilfer-proof section 22 of the closure 11 is folded under this shoulder. Above the pilfer-proof section 22 is shown one of the tongues 32 formed by the lancing blade in the apparatus just described. It is important to note that the bulge 17 in the closure 11 extends far enough out so that the inwardly directed tongue 32 does not come into contact with the wall of the container 14 above the shoulder 76. Thus when the closure 11 is removed from the container and replaced on the container, the tongues 32 do not scrape on the container surface. One effect of such scraping would be to leave an undesired metallic deposit which, in the case of certain chemicals frequently found in beverages, could lead to an unsightly dark band. Another adverse effect of such contact between the tongues 32 and the container 14 is an increase in the torque required to remove the closure from the container. Thus, the bulge 17 must extend outwardly farther than the tongues 32 extend inwardly.

FIG. 13 is an enlarged view showing precisely how the pilfer-proof section 22 is scored in the closure 11 of FIG. 1. As may be seen, the scoring mark 23 ends just below the bottom of the bridge 21 and below the bulge 17. The region of the bridge 21 just above the end of the scores 23 and to the left and right of the end of the scores acts as a hinge, or more precisely one part of a hinge, for the two segments of the pilfer-proof section 22 on each side of the scores 23.

When the closure is removed from the bottle by being unscrewed, each of the scores 23 breaks, as shown in FIG. 14, and divides to form a V-shaped notch 23a. The two segments of the pilfer-proof section 22 on the sides of the notch 23a spread apart enough to allow them to pass over the glass collar on the neck of the bottle and to allow the entire closure, including the pilfer-proof section 22, to be removed as a unit. This is contrary to the practice of present, unscored pilfer-proof sections, which normally break at the bridges. However, by virtue of the present embodiment, the bridges 21 are made stronger than such bridges have been made heretofore, and they do not break when the closure is removed. For example, previously bridges have had a width of approximately 0.030 inch; but in accordance with the present invention, they should preferably be somewhat broader, although it is not essential that they be. I have found that by making the bridges with a width of about 0.090 inch in the direction transverse to the axis of the cap, they provide an optimum bending characteristic.

When the closure is unscrewed, each of the segments of the pilfer-proof section 22 twists the half section of the bridge 21 at each of its ends just enough to allow the inwardly directed lower edge of the pilfer-proof section 22 to slide past the shoulder and threads on the bottle. But due to the fact that there are preferably about eight such segments in the complete pilfer-proof section 22, none of the segments has to pivot outwardly very far. On the other hand, one of the disadvantages of providing too many scoring marks is that some of them may not rupture. This would cause the aforementioned, undesired twisting of the closure to a skewed position. Therefore, the corners of each segment adjacent each of the notches 23a are still nearly in line with each other and there are no outwardly extending sharp edges to cut the person removing the closure from the bottle. Furthermore, by scoring the pilfer-proof section 22 from the outside, the edges of the notches are quite round and safe, as shown in FIG. 15. If there were only four such segments, for example, each one would have to turn considerably farther out and the points at the edges of each of the notches 23a would be a real danger to anyone trying to remove such a closure.

Claims

What is claimed is:

1. A closure for a container having a threaded section at the end of its neck and a ridge that extends outwardly from the neck below the threaded section, said closure comprising:

A. a closed end;

B. a skirt extending from the perimeter of said end and comprising:

1. a pilfer-proof section at the edge of said skirt remote from said closed end,

2. a cylindrical section between said closed end and said pilfer-proof section to engage said threaded section of said container,

3. an outwardly bulged section between said cylindrical section and said pilfer-proof section, and

4. a plurality of substantially evenly spaced slots encircling said skirt in said bulged section, said slots being defined by bridges of the material of said bulged section and by tongues of material of said bulged section pivoted inwardly, the total distance that each of said tongues extends inwardly being less than the radially outward extension of said bulged section, whereby the innermost end of said tongues do not reach said container; and

C. a plurality of scores extending from the edge of said skirt most remote from said closed end toward said closed end and inwardly from the outer surface of said skirt, and parallel to the axis, the depth of said scores being less than the thickness of said pilfer-proof section, said scores being equal in number to the number of said bridges and being angularly spaced apart by the same angle as said bridges so that all of said scores have substantially the same angular orientation with respect to a corresponding one of said bridges.

2. The closure of claim 1 in which said pilfer-proof section is initially flared out approximately 6.degree..

3. The closure of claim 1 in which there are eight of said scores.

4. The closure of claim 1 in which said scores extend from the edge of said skirt to a point below said bulged section.

5. The closure of claim 4 in which each of said scores is in line substantially with the center of a corresponding one of said bridges.

6. The closure of claim 5 in which each of said scores extends across the central portion of a corresponding one of said bridges.

7. The closure of claim 1 in which said scores extend from the edge of said pilfer-proof section remote from said closed end toward, but not into, each of said slots.

8. The closure of claim 1 in which each of said scores extends toward, but not into, the center of a respective one of said tongues.

9. The closure of claim 1 comprising, in addition: a plurality of lines extending across said scores whereby the breaking of said scores interrupts said lines.

10. The closure of claim 1 in which said closure is scored to a depth of at least approximately 70 percent of the thickness of the material of said closure.