US3283946A

US3283946A - Can end

Info

Publication number: US3283946A
Application number: US426536A
Authority: US
Inventors: Frederick J Stec
Original assignee: Continental Can Co Inc
Current assignee: Continental Can Co Inc
Priority date: 1965-01-19
Filing date: 1965-01-19
Publication date: 1966-11-08
Anticipated expiration: 1983-11-08
Also published as: AT258782B

Description

F. J. STEC Nov. 8, 1966 CAN END Filed Jan. 19, 1965 INVENTOR Unite ttes Patent @dice 3,283,946 Patented Nov. 8, 1966 3,283,946 CAN END Frederick J. Stec, @ak Lawn, Ill., assigner to Continental Can Company, liuc., New York, N.Y., a corporation of New Yori:

Filed Jan. 19, 1965, Ser. No. 426,536 Claims. (Cl. 220-54) This invention relates in general to new and useful improvements in the construction of containers and more specifically to a novel can end of the easy opening type.

This invention particularly relates to can ends intended to be utilized as closures for cans containing products packaged under pressure. It will be readily apparent that in order that the can ends may be of the easy opening type, once an initial rupture of such a can end has occurred, the pressure within the can, if not vented, will act upon the tear out portion of the can end and serve to automatically blow out the tear off portion of the can end in an uncontrolled manner. This invention proposes to eliminate the possibility of the tear out portion of the can end from being blown out in two ways. First, it is proposed to make the tear out portion of the can end very narrow so that the total force exerted thereon will be reduced accordingly. Secondly, it is proposed to provide the can end with a tab which is an extension of the tear strip and the tab being separated from the starting end portion of the tear strip bv a transverse score line whereby when an upwardly directed force is exerted on the starting end portion of the tear strip, the tab will also be lifted and rupture of the can end will occur at the intersection between the tab and the tear strip so as to first form a vent opening in the can end in a manner whereby uncontrolled blow off of the tear strip is prevented.

Another object of this invention is to 'provide a can end of the type which includes a removable panel portion which is in the form of a tear strip, the removable panel portion being defined by a score line and having a starting end portion which is defined by a pair of score line portions, the score line portions having extensions which generally outline a tab disposed at the continuation of the starting end portion of the removable panel, and there being a transverse score line portion separating the tab from the starting end portion so that initial rupture occurs between the starting end portion and the tab and venting of the can end prior to the tearing away of the removable panel occurs.

Another object is to provide a novel can end in accordance with the foregoing wherein the transverse score line portion is arcuate and opens away from the starting end portion whereby there is a progressive rupture of the can end along the transverse score line portion and at the same time the tendency for the can end to rupture along those portions of the score line defining the removable panel is restricted.

With the above and other objects in view that will hereinafter appear, the nature of the invention will be more clearly understood by reference to the following detailed description, the appended claims and the several views illustrated in the accompanying drawing:

In the drawing:

FIGURE 1 is a fragmentary top perspective view of a can having the upper end thereof closed by a can end formed in accordance with this invention.

FIGURE 2 is an enlarged fragmentary vertical sectional view taken along the line 2 2 of FIGURE 1 and shows the specific constructional details of the can end.

FIGURE 3 is a fragmentary horizontal sectional view taken along the line 3 3 of FIGURE 2 and shows the specic outline of the removable panel portion of the can end and the tab aligned therewith.

FIGURE 4 is a fragmentary vertical sectional View similar to FIGURE 2 and shows the pull tab which is attached to the removable panel in an initially lifted position and the end panelrof the can end partially distorted.

FIGURE 5 is another fragmentary vertical sectional view similar to FIGURE 2 and shows the can end after an initial rupture thereof has occurred with there being venting of the gases from within the can through the vent opening which is formed.

FIGURE 6 is still another enlarged fragmentary vertical sectional View similar to FIGURE 2 and shows the can end after the venting of the gas from within the can has been completed and the pull tab having been moved to a position whereby tearing of the removable panel from the can end has begun.

Referring now to the drawing in detail, it will be seen that there is illustrated in FIGURE 1 a can formed in accordance with this invention. The can is generally referred to by the numeral 10 and includes a conventional type of can body 11 which will have the lower end thereof (not shown) closed in a normal manner. The upper end of the can body 11 is closed by means of a can end, which is generally referred to by the numeral 12. The can end 12 is formed in accordance with this invention and is secured to the can body 11 by means of a conventional double seam 13.

The can end 12 with the exception of the easy opening feature thereof, may be of a conventional construction and includes a recessed end panel 14. The end panel 14 is provided with a removable panel portion or tear strip 1S which, in the illustrated form of the invention, is specifically designed for the dispensing of liquids, but the invention is not so limited. The removable panel portion 15 is defined by a weakening line formed in the end panel 14, the weakening line preferably being in the form `of a score line 16. The configuration of the removable panel portion 15 is such so as to define a starting end portion 17 and an enlarged terminal end portion 18 which are connected together by an intermediate connecting strap 19. The starting end portion 17 is provided With an integral rivet 20 by means of which a pull tab 21 is rigidly secured to the starting end portion 17. Inasmuch as the pull tab 21 in itself does not constitute a part of this invention, it will not be described in detail.

It is to be noted that the removable panel portion or tear strip 1S is so contigurated wherein the connecting strap 19 thereof is narrower than either the starting end portion 17 or the terminal portion 18. By making the connecting strap 19 as narrow as possible, yet retaining therein suicient strength to facilitate the tearing out of the removable panel portion 15, it will be seen that the effective area of the removable panel portion 15 in the vicinity of the connecting strap 19 is reduced to a minimum. Inasmuch as the total blow `off force exerted on the removable panel portion 15 is directly proportional to the amount of area on which the pressure within the can 10 is effective, it will be seen that the blow off force exerted on the removable panel portion 15 is held to a minimum. Furthermore, by making the connecting strap 19 of a minimum width, it will be seen that after the initial rupture of the can end 14 occurs, and tearing away of the starting end portion 17 from the end panel 18 has been completed, the force per linear dimension of the connecting strap 19 is retained at a minimum and therefore, the resistance to uncontrolled tearing out of the removable panel portion 15 is greatly increased.

It is to be understood that normally the starting end portion of a removable panel or tear strip of an easy opening can is rounded and generally concentric with respect to the integral rivet carried thereby. However, in the present instance the score line 16 has portions thereof, referred toby the numeral 22, extending generally parallel on opposite sides of the integral rivet 2d. Furthermore, the portions 22 of the score line 16 have extensions 23 which extend beyond the removable panel portion 19 and generally define a tab 24,. The tab 24 is in the form of an extension of the removable panel portion 15 and is separated therefrom by a transverse score line 2'5 which extends between the score line portions 22 and intersects the same at the intersections of the extensions 23 therewith. It is to be noted that the transverse score line 25 is arcuate in outline and opens towards the tab 24.

Referring now to FlGURE 2 in particular, it will be seen that the pull tab 21 normally overlies the transverse score line 25 and protects the end panel 14 against accidental rupture along the score line 25. However, when the' pull tab 21 is elevated in the normal manner for removing the. removable panel portion 15, it will he seen that an upwardly directed force is applied to the starting end portion 17 and there is an upward bowing of the end panel 14 in the vicinity of the transverse score line 25. It will be readily apparent that the position of the transverse score line 25 is such that this is the portion of the end panel 14 which first ruptures. Inasmuch as the transverse score line 2S is arcuate7 it will be seen that the rupture of the end panel 14 will normally start at the center of the score line 25 and progress towards the opposite ends thereof.

When the end panel 14 ruptures along the score line 25, a vent opening is formed in the end panel 14, as at 26` in FIGURE 5. lt is to be noted that the vent opening 26 is still shielded by the pull tab 21, but at the same time, the pull tab 21 is suiiciently spaced from the vent opening 26 to permit the escape of gases from the can 10 throu-gh the vent opening 26. On the other hand, the position and size of the vent opening 26 is such that the product packaged within the can does not escape with the gases as the gases are vented from within the can lil.

It is also pointed out at this time that inasmuch as the transverse score line 2S is curved away from the starting end portion 17, there is little tendency for the continued rupture of the end panel 14 along the score line portions 22 whereas the tendency for the end panel 14 to rupture is generally along the extensions 23. Furthermore, the relationship of the transverse score line 25 to the score line portions 22 is such that relatively sharp corners 27 are formed at the opposite ends of the score line 25.

After the initial rupture of the end panel 14 and the distortion thereof to the position shown in FGURE 5, a further upwardly directed pull on the pull tab 21 and movement of the pull tab 21. generally to the left in FIG- URE 6 will result in the tearing away of the removable panel portion from the remainder of the end panel 14 alongr the score line 16. Although the tab 2d will rei main as a part of the end panel 14, it will be readily apparent that it will in no way be disadvantageous to have it remain a part of the end panel.

It is also pointed out at this time that when certain beverages are packaged in cans, particularly soft drinks, the pressure within the can has a tendency to blow out the weakened portion of the can end. Should this accidentally occur with the can end 12, it will be apparent that the blow out will occur along the transverse score line with the result that the vent opening 26 will be formed and there will not be a blowing oif of the removable panel 15. Thus, the possibility of one becoming accidentally injured by the blowing oif of the removable panel is eliminated.

Although only a preferred embodiment of the invention has been specifically illustrated Aand described herein, i-t is to be understood that minor variations may be made in the disclosed can end construction without departing from the spirit and scope of the invention, as defined in the appended claims.

I claim:

1. An easy opening can end particularly adapted for use `as a closure for liquids packaged under pressure, said can end having a removable panel delined by a peripheral score line and including a starting end portion, a large terminal end portion and an elongated connecting strap between said end portions, and said connecting strap being materially narrower than each of said end portions whereby the force exerted on said connecting 'strap by pressure within an associated can is held to minimum thereby preventing .the accidental bl-ow out of said removable panel xafter the initial rupture of the can end along said score line.

Z. The can end of claim 1 wherein a pull tab is secured to said starting end portion to facilitate -t-he rupture of the can end.

3. The can end of claim 1 wherein said score line has extensions defi-ning` a tab forming yan extension of said starting end por-tion with -a portion 'of said score line separating said tab from said starting end portion whereby when a lifting force .is exerted on said starting end portion said tab will lift therewith and initially rupture along said score line portion.

4. An easy opening can end particularly adapted for use as a closure for products packaged under pressure, said can end having -a .tear strip defined the-rein by a Iscore line and said tear strip having a starting end portion, `and said score line having extensions deiining a tab forming an extension of said starting end portion with a portion of said score line separating said tab from said starting end portion whereby when a lifting force is exerted on said starting end portion said tabwill lift therewith and initially rupture along said score line portion.

5. The can end of claim 4 wherein said score line portion is arcuate t-o provide for a progressive rupturing of said can end along said score line portion.

6. FBhe can end of claim 4 wherein said score line portion is arcuate to provide for a progressive rupturing of said can end along said score line portion, said score line portion opening .towards said tab.

7. An easy opening can end particularly adapted for use as a closure for products packaged under pressure, said can end having a tear strip defined therein by a pair of score line portions disposed gene-rally in side-by-side spaced relation, said score Iline portion-s having terminal parts defining a t-ab for-ming an extension of s-aid tear strip, and .a transverse s-core line portion extend-ing between the first mentioned score line portions separating said ta'b from a starting en-d portion of said tear strip whereby when a lifting force is exerted on said star-ting end portion said -tab will lift therewith and initially rupture along said score line portion.

S. The can end of claim 7 lwherein said score line portion is arcuate to provide for a progressive rupturing of said can end along said score line portion.

9. The can end of claim 7 wherein said score line portion is arcuate to provide lfor a progressive rupturing of said can en-d along said score line portion, said score line portion opening toward-s said tab.

10. The can end of claim 7 wherein a pull tab is secured to said starting end portion Aand projects therefrom as an exten-sion of said tear strip, said pull tab overlying said transverse score line portion and protecting the can end .against accidental rupture thereof lalong said transverse score line portion.

No references cited.

THERON E. CONDON, Primary Examiner.

G. T. HALL, Assistant Examiner.

Claims

1. AN EASY OPENING CAN END PARTICULARLY ADAPTED FOR USE AS A CLOSURE FOR LIQUIDS PACKAGED UNDER PRESSURE, SAID CAN AND HAVING A REMOVABLE PANEL DEFINED BY A PERIPHERAL SCORE LINE AND INCLUDING A STARTING END PORTION, A LARGE TERMINAL END PORTION AND AN ELONGATED CONNECTING STRAP BETWEEN SAID END PORTIONS, AND SAID CONNECTING STRAP BEING MATERIALLY NARROWER THAN EACH OF SAID END PORTIONS WHEREBY THE FORCE EXERTED ON SAID CONNECTING STRAP BY PRESSURE WITHIN AN ASSOCIATED CAN IN HELD TO MINIMUM THEREBY