US3208618A

US3208618A - Crown cap

Info

Publication number: US3208618A
Application number: US328870A
Authority: US
Inventors: Spector Morris
Original assignee: National Can Corp
Current assignee: Rexam Beverage Can Co
Priority date: 1963-12-09
Filing date: 1963-12-09
Publication date: 1965-09-28
Anticipated expiration: 1982-09-28

Description

Sept. 28, 1965 M. SPECTOR 3,208,618

CROWN CAP Filed. Dec. 9, 1963 INVENTOR.

United States Patent 3,208,618 CROWN CAP Morris Specter, Highland Park, Ill., assignor to National Can Corporation, Chicago, Ill., a corporation of Delaware Filed Dec. 9, "1963, Ser. No. 328,870 2 Claims. (Cl. 215-46) This invention relates to improvements in crown caps, particularly a crown cap that may be removed from the container upon which it is mounted without the use of a tool opener.

The crown cap is of the type stated in which the cap has a plurality of upwardly extending tabs circumferentially spaced around the skirt of the cap and which may be grasped to tear the cap and facilitate its removal from the container. It is an object of the present invention to provide a cap of the type stated with a plurality of score lines on the inside of the crown to facilitate bending of the crown after tearing of the tabs, thereby facilitating removal of the cap from the container. By having the score lines on the inside of the crown, the score lines do not interfere with lithographing the caps nor do the score lines tend to mar the appearance of the finished cap.

It is a further object of the present invention to provide a cap of the type stated in which the score lines extend from adjacent to but spaced from the tops of the tabs so that the score lines do not Weaken the body of the cap in the regions between the ends of the score lines and the tops of the tabs.

It is an additional object of the present invention to provide a cap of the type stated that does not interfere with or require modification of high speed capping machinery in order to mount the caps onto the containers.

The attainment of the above and further objects of the present invention will be apparent from the following specification taken in conjunction with the accompanying drawing forming a part thereof.

In the drawing:

FIGURE 1 is a top plan view of a crown cap constructed in accordance with and embodying the present invention;

FIGURE 2 is a vertical sectional view through the central axis of the cap shown mounted in place on the neck of a container;

FIGURE 3 is a side elevational view of the cap shown mounted on the container;

FIGURE 4 is a top plan view of a modified form of crown cap that embodies the present invention; and

FIGURE 5 is a transverse sectional view, on an enlarged scale, of a portion of the crown and sealing disc therebelow in the region of one of the score lines.

Referring now in more detail to the drawing 1 desig nates a crown cap that comprises a metal body 3 of sheet metal, such as aluminum or black plate having a top or crown 5 and an annular skirt 7 that depends from the periphery of the crown 5 and terminates in a rim or free end 9. The bottom portion 13 of the skirt 7 is outwardly directed and generally conical while the upper portion 15 of the skirt 7 is generally cylindrical. The skirt 7 is corrugated by circumferentially spaced flutes 17 that extend from the free end 9 upwardly toward the crown 5. The flutes 17 extend across the lower portion 13 and then upwardly into the upper or cylindrical portion 15.

Formed in the body 3 are a plurality of inverted U- shaped slits 19 that define identical, upwardly extending, circumferentially spaced

tear tabs

21, 21, 21. Each slit has a curved bight 23 that defines the top of the tab 21 with the highest point of the bight lying approximately at the curved juncture of the skirt and the crown, and preferably below the crown. The

sides

25, 27 of each slit, which define the sides of the tabs 21, terminate at spaced points above the free end 9 of the skirt 7, thereby to leave

regions

29, 31 of soild metal between the terminals of the slits and the free end 9 of the skirt. Preferably also the

sides

25, 27 of each slit lie along the ridges of two adjacent flutes 17. The three tabs may be equally spaced around the periphery of the skirt 7.

Formed on the underside of the crown 5 are three

straight score lines

33, 33, 33. The score lines 33 extend between the

tabs

21, 21, 21 but the respective terminals 35 of the score lines 33 stop a substantial distance short of the bights 23 of the slits, thereby to leave gaps 39 of unscored metal between the terminals 35 of the score lines and the tabs 21. This provides a continuous unweakened joint between the crown and the skirt in the region between the tops of the tabs and the terminals of the score lines. One of the score lines 33 is shown exaggerated in FIGURE 5 for purposes of illustration only. Actually, the maximum distance between the

sides

34, 34 of the score line 33 is close to zero.

The cap 1 has a conventional flexible gas impervious yielding sealing liner 41 underlying the crown 5 and is of a diameter of approximately that of the internal diameter of the skirt at the crown. The liner 41 may be of cork with an impermeable plastic disc adhesively secured to the underside thereof. The liner is held onto the cap in any standard manner.

The cap 1 may be mounted on the container 11 by conventional high speed capping machinery. During the capping operation, the skirt 7 is radially outwardly flexed to snap over the container bead 43 and then moves under its natural resiliency, or is mechanically moved, radially inwardly into gripping engagement with the underside of the container bead 43 to hold the cap onto the container bead by the hoop strength of the distended skirt. The portions 45 of the skirt between the flutes engage the bottle bead as shown in FIGURES 2 and 3. The gripping of the container bead by the skirt also presses the sealing liner 41 downwardly into firm sealing engagement with the top of the container bead 43. The

continuous regions

39, 39 on opposite sides of each tab help to press the liner 41 downwardly at each tab.

When it is desired to remove the cap 1, the tear tabs 21 are grasped by inserting the fingernail behind the tab. The tab is then pulled outwardly and then downwardly, as shown in dotted lines in FIGURE 2. This tears one or more of the

regions

29, 31 of metal adjacent to each of the respective tabs 21 and thereby breaks the hoop strength of the skirt. The cap may then be removed from the container bead, and to facilitate such removal, the body 3 may be bent upwardly around one or more of the score lines 33.

It is customary to lithograph the metal used to form the caps so that the exposed surface of the crown is decorated with the name, trademark, or other design. By having the score lines 33 on the underside of the crown, such score lines do not interfere with the lithography nor do they tend to mar the decorative appearance of the crown of the cap.

It is also possible to provide a modified form of cap that is shown in FIGURE 4. The cap of FIGURE 4 is similar to the cap previously described except that only two score lines on the underside of the

crown

33, 33 are used. Furthermore, the three tabs 21a, 21b, 21c, which are all identical to the tabs 21, are spaced apart such that the are between the tabs 21a and 21b is less than 180 degrees, the arc between the tabs 21b and 21c is less than 180 degrees, but the are between the tabs 21a and 210 and passing through the tab 21b is greater than 180 degrees. The three tabs 21a, 21b and 210 may, of course, be equally spaced just as in the case of the cap of FIGURE 1, or preferably are unequally spaced, the distance between the tabs 21a, 21b and 21b, 21c being each slightly more than 90 degrees and the distance between 210, 21a being greater, but less than 180 degrees.

Except for the tabs and the score lines the crown cap is otherwise of conventional construction as shown for example in Ramsay Patent 1,899,210, Atwood Patent 2,156,258, and Shannon Patent 2,433,629, the disclosures of which are incorporated herein by reference. Furthermore, the

tabs

21, 21, 21 may, if desired, be constructed in the manner shown by the aforesaid Ramsay patent.

In copliance with the requirements of the paten statutes I have herein shown and described a preferred embodiment of the invention. It is, however, to be understood that the invention is not limited to the precise construction herein shown, the same being merely illustrative of the principles of the inevntion. What is new and is desired to be secured by Letters Patent is:

1. A crown cap comprising a body having a crown and peripheral skirt surrounding and projecting away from the crown, a sealing liner adjacent to the crown and surrounded by the skirt, said skirt including a curved portion that is joined to the crown, said skirt being corrugated by circumferentially spaced flutes formed in and extending from the free end of the skirt toward the crown with the skirt forming a continuous hoop so that the skirt may be radially inwardly distended throughout its entire extent into gripping engagement with a bead on a container neck to hold the cap in place on the container neck by the hoop strength of the distended skirt, first, second and third circumferentially spaced tear tabs on the body to facilitate removal of the cap from the container neck, said tabs each projecting toward the crown and each being defined by a generally U-shaped slit in the body with the bight of the U defining the end of the tab and with said bight being substantially entirely in the skirt, the portions of the slit defining the sides thereof terminating at spaced points adjacent to but spaced from said free end of the skirt so that any tab may be pulled to tear the part of the skirt between the ends of the slit and said free end, the are between the first and second tabs being less than 180 degrees and the are between the first and third tabs and which passes through the second tab being greater than 180 degrees, said crown having at least two chord-like score lines that are radially outwardly of the center of the crown and of a depth less than that of the material of the crown and along any of which the body may be bent after tearing of two of the tabs, each score line lying between two of the tabs and terminating at its opposite ends in the crown adjacent to but spaced from each of said two tabs, the crown being its normal thickness at its peripheral portion to provide a continuous annular unweakened region at the periphery of the crown to assist in pressing the liner against a container neck at said continuous region.

2. A crown cap according to claim 1 in which the score lines are on the inside .of said crown.

References Cited by the Examiner UNITED STATES PATENTS 1,899,210 2/33 Ramsay 215-46 2,156,258 5/39 Atwood 2l5-46 2,433,629 12/47 Shannon -46 FOREIGN PATENTS 896,107 5/62 Great Britain.

FRANKLIN T. GARRETT, Primary Examiner.

GEORGE O. RALSTON, Examiner.

Claims

1. A CROWN CAP COMPRISING A BODY HAVING A CROWN AND PERIPHERAL SKIRT SURROUNDING AND PROJECTING AWAY FROM THE CROWN, A SEALING LINER ADJACENT TO THE CROWN AND SURROUNDED BY THE SKIRT, SAID SKIRT INCLUDING A CURVED PORTION THAT IS JOINED TO THE CROWN, SAID SKIRT BEING CORRUGATED BY CIRCUMFERENTIALLY SPACED FLUTES FORMED IN AND EXTENDING FROM THE FREE END OF THE SKIRT TOWARD THE CROWN WITH THE SKIRT FORMING A CONTINUOUS HOOP SO THAT THE SKIRT MAY BE RADIALLY INWARDLY DISTENTED THROUGHOUT ITS ENTIRE EXTENT INTO GRIPPING ENGAGEMENT WITH A BEAD ON A CONTAINER NECK TO HOLD THE CAP IN PLACE ON THE CONTAINER NECK BY THE HOOP STRENGTH OF THE DISTENDED SKIRT, FIRST, SECOND AND THIRD CIRCUMFERENTIALLY SPACED TEAR TABS ON THE BODY TO FACILITATES REMOVAL OF THE CAP FROM THE CONTAINER NECK, SAID TABS EACH PROJECTING TOWARD THE CROWN AND EACH BEING DEFINED BY A GENERALLY U-SHAPED SLIT IN THE BODY WITH THE BIGHT BEING OF U DEFINING THE END OF THE TAB AND WITH SAID BIGHT BEING SUBSTANTIALLY ENTIRELY IN THE SKIRT, THE PORTIONS OF THE SLIT DEFINING THE SIDES THEREOF TERMINATING AT SPACED POINTS ADJACENT TO BUT SPACED FROM SAID FREE END OF THE SKIRT SO THAT ANY TAB MAY BE PULLED TO TEAR THE PART OF THE SKIRT BETWEEN THE ENDS OF THE SLIT AND SAID FREE END, THE ARC BETWEEN THE FIRST AND SECOND TABS BEING LESS THAN 180 DEGREES AND THE ARC BETWEEN THE FIRST AND THIRD TABS AND WHICH PASSES THROUGH THE SECOND TAB BEING GREATER THAN 180 DEGREES, SAID CROWN HAVING AT LEAST TWO CHORD-LIKE SCORE LINES THAT ARE RADIALLY OUTWARDLY OF THE CENTER OF THE CROWN AND OF A DEPTH LESS THAN THAT OF THE MATERIAL OF THE CROWN AND ALONG ANY OF WHICH THE BODY MAY BE BENT AFTER TEARING OF TWO OF THE TABS, EACH SCORE LINE LYING BETWEEN TWO OF THE TABS AND TERMINATING AT ITS OPPOSITE ENDS IN THE CROWN ADJACENT TO BUT SPACED FROM EACH OF SAID TWO TABS, THE CROWN BEING ITS NORMAL THICKNESS AT ITS PERIPHERAL PORTION TO PROVIDE A CONTINUOUS ANNULAR UNWEAKENED REGION AT THE PERIPHERY OF THE CROWN TO ASSIST IN PRESSING THE LINER AGAINST A CONTAINER NECK AT SAID CINTINUOUS REGION.