US3215306A

US3215306A - Pull tab

Info

Publication number: US3215306A
Application number: US345348A
Authority: US
Inventors: Simpson Justin; John S Bozek
Original assignee: Continental Can Co Inc
Current assignee: Continental Can Co Inc
Priority date: 1964-02-17
Filing date: 1964-02-17
Publication date: 1965-11-02
Anticipated expiration: 1982-11-02
Also published as: MY6800026A; GB1017167A

Description

NOV- 2, 1965 J. slMPsoN ETAL 3,215,306

PULL TAB Filed Feb. 17, 1964 mil@ of the container.

tabs `are raw edges.

3,215,306 PULL TAB Justin Simpson, Elmhurst, and .lohn S. Bozek, Chicago, Ill., assignors to Continental Can Company, Inc., New York, N.Y., a corporation of New York Filed Feb. 17, 1964, Ser. No. 345,348 Claims. (Cl. 220-454) `removable portion of the container immediately adjacent the starting portion of the score line so that when an `upwardly directed force is applied to the pull tab, the

container will be ruptured along the starting portion of the score line, after which the removable portion of the container may be readily removed by exerting a tension -on the pull tab suicient to tear the container along the score line. The pull tabs presently in use have met with numerous objections. In the first place, if the pull tabs are not of sufficient rigidity, when an initial upwardly directed force is applied thereto, in lieu of rupturing the container along the starting portion of the score line, the pull tab will bend or fold and not function to transmit the upwardly directed force to the removable portion On the other hand, the pull tab must be retained as thin as possible due to the fact that the pull tab must be entirely recessed within the end of the container in order to avoid interfering with any mechanism which operates on the container. It is, therefore, a primary lobject of this invention to provide a novel sheet metal pull tab which is of a cross section wherein the thickness of the pull tab is held at a minimum while the necessary strength isv imparted to the pull tab.

A major deficiency of existing pull tabs is that they i are stamped from sheet metal and the edges of the pull Accordingly, when one grips the existing pull tab and there is any slippage between ones ngers and the pull tab, very often the raw edges of the pull tab cut or slice ones fingers. It is, therefore, another object of this invention to provide a novel sheet metal pull tab which is provided with a hem extending about the entire portion of the pull tab which is gripped by ones fingers in the normal use of the pull tab, the hem serving to both protect the raw edge of the metal of the pull tab and reinforce the pull tab against undesired bending or folding.

Still another deliciency of existing pull tabs is that when the pull tabs are made to lie closely adjacent the container end, it is extremely difficult to engage ones fingers beneath the pull tab for the purpose of exerting the necessary upwardly directed force thereon. In the average container construction, approximately 14 inch pounds are required to effect the rupture of the associated container along the score line starting portion. It is obvious that such a lifting force cannot be applied with ones finger nails beneath a pull tab, and therefore, it is necessary that ones fingers can readily engage under the end of the pull tab. In view of this, it is still another object of this invention to provide a novel pull tab which is formed of sheet metal and which is of a rigid construction, the pull tab having a free end thereof upwardly offset from the remainder of the pull tab whereby the extreme free end of the pull tab may be readily engaged and lifted so that the pull tab may transmit to the con- United States Patent O ice tainer the necessary force to effect the rupture of the container along the starting portion of the score line thereof.

A further difficulty encountered with existing pull tabs is that after the initial rupture of a container occurs, sufficient tension must be applied to the removable portion of the container to effect the tearing thereof from the container. As a result, a proportionally large pull must be exerted on the pull tab. However, since the pull tab is formed of sheet metal which has very smooth surfaces, it is difficult to obtain the necessary grip on the pull tab. Therefore, it is a still further object of this invention to provide a novel sheet metal pull tab which is so configurated whereby not only is the desired strength imparted to the pull tab, but also effective gripping surfaces are presented.

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 of the easy opening type particularly adapted for dispensing a liquid and shows the can provided with a pull tab formed in accordance with this invention.

FIGURE 2 is an enlarged plan view of the pull tab of FIGURE 1 and shows the specific outline thereof.

FIGURE 3 is an enlarged longitudinal vertical sectional View taken along the line 3 3 of FIGURE 2 and shows the specific longitudinal cross section of the pull tab.

FIGURE 4 is an enlarged transverse vertical sectional View taken along the line 4*-4 of FIGURE 3 and shows the specific transverse cross section of the pull tab.

Referring now to the drawing in detail, reference is first made to FIGURE 1 wherein there is illustrated a conventional type of container which is generally referred to by the numeral 10. The illustrated container 10 is in the form of a conventional beverage can and includes a can body 11 to which there is secured a can end 12 of the easy opening type by means of a conventional double seam 13. The can end 12 includes an end panel 14 which is provided with a score line 15 defining a tear out portion 16. The tear out portion 16 includes an elongated part 17 which includes the starting part of the tear out portion 16 and which carries an integral rivet 18 which is utilized in the securement of a pull tab to the tear out portion 16 for the purpose of facilitating the rupture of the end panel 14 along the score line 15. The illustrated pull tab 2t) incorporates the specific features of this invention.

Referring now to the drawings in detail, it will be seen from FIGURE 2 that the pull tab 20 is generally rectangular in outline and from FIGURE 4 that the pull tabl 20 is of a shallow winged -channel cross section. In cross section the pull tab 20 includes a central, lowermost web 21 which is provided along the opposite sides thereof With upstanding flanges 22. A wing flange 23 extends outwardly from each of the upstanding flanges 22. The wing flanges 23 lie in a plane disposed in spaced parallel relation to the plane of the web 21. The wing anges 23 terminate at their outer edges in inwardly and reversely turned hems 24.

In FIGURE 2 it is shown that the left end of the web 21 is rounded as at 25. An upstanding ange portion 26 extends around the rounded end 25 of the web 21. The upstanding flange portion 26 connects together the two flanges 22, and the anges 22 and the ange p0rtion 26 may be considered a continuous flange.

It will be readily apparent that the upstanding flange portion 26 is generally U shaped in outline. A Similarly shaped wing ange portion 27 extends outwardly from the upstanding flange portion 26 and connects together the two wing flanges 23. The outer edge of the wing flange portion 27 also terminates in an inwardly turned hem 28. The hem 28 connects together the hems 24 and the

hems

24 and 28 may be considered to form a continuous hem while the

wing flanges

23 and 27 serve to form a continuous wing flange.

It is to be noted that the web 21 is of a constant width for a major portion of the length thereof. However, remote from the curved end portion the web 22 is widened as at 29. The web 21 is widened to provide sufficient space for the formation of an opening therethrough. The opening 30 receives the rivet 18 with the head of the rivet 18 tightly clamping against the web 2.1 surrounding the opening 30. It is also to be noted that the upstanding flanges 22 are contoured in accordance with the change in shape of the web 21 and define a space of sufficient size to receive the head of the rivet 18. rAlthough the web 21 is of an increased width at the right-hand end of the pull tab 20 and the upstanding flanges 22 follow the contour of the web 21, the outer edges of the wing flanges 23 remain straight and the wing flanges 23 are decreased in width in accordance with the increase in width of the web 21.

It is to be noted that the pull tab 20 is provided with a pointed end edge 31 at the end thereof adjacent the opening 30. The pointed end edge 31 includes a rounded nose portion 32 which may be brought into contact with the end panel 22 when utilizing the pull tab 20 for the purpose of rupturing the end panel 12 along the score line 15.

It is to be understood that when the pull tab is positioned on the end panel 14, it is tightly clamped against the surface thereof by the clamping action of the rivet 18. In order to facilitate the engagement of the end of the pull tab 20 remote from the rivet 18 and the lifting of the pull tab 20, the end of the pull tab 20 remote from the rivet 18 is folded upwardly along a transverse fold line 33. The folding of the pull tab 20 along the fold line 33 results in the wing flange portion 27 lying in a plane disposed in angular relationship to the plane of the web 21. In this manner the hem 28 and the underside of the wing flange portion are elevated above the upper surface of the end panel 14 and ones fingers may be engaged therebeneath to effect the gripping thereof and exerting an upwardly directed force thereon.

It will also be apparent that the generally U shaped upstanding flange portion 26, in association with the generally U shaped hem 28, will afford proper gripping surfaces for ones forenger and thumb. Thus, the pull tab 20 may be effectively gripped for both the initial upward lifting thereof and the application of a tensile stress to the tear out portion 16 after the initial rupture of the end panel 14.

A careful study of the pull tab 20 will make it readily apparent that the pull tab may be readily formed from `sheet metal in a simple series of stamping and forming operations so that the pull tab 20 is economically feasible. At the same time, it will be readily apparent that due to the specific winged channel cross section of the pull tab 20, a maximum strength may be obtained with a minimum of metal and at the same time the thickness of lthe pull tab may be held ,to a minimum as is required in order to properly recess the pull tab 20 within the confines of the can end 12. The

hems

24 and 28 serve the dual purpose of placing the raw edges of the metal from which the pull tab 20 is formed in a position wherein they cannot be readily engaged with ones fingers and they serve to reinforce the edge portions of the pull tab 20. These advantageous features are in addition to the aforementioned advantageous grip features of the pull tab.

Although only a preferred embodiment of the invention has been specifically illustrated and described herein, it is to be understood that minor modifications may be made therein within the spirit and scope of the invention, as defined by the appended claims.

We claim:

1. A sheet metal pull tab particularly adapted for attachment to a tearable container portion, said pull tab being of a shallow winged channel cross section and including a web having sides and ends, a narrow upstanding flange extending along the sides and one end of said vweb and a wing flange extending outwardly from said upstanding flange along the sides and the one end of said web, and an inturned hem along the periphery of said wing flange in underlying relation to said wing flange thereby forming a rigid structural unit.

2. The sheet metal pull tab of claim 1 wherein said web is widened at the other end thereof to provide clearance for a beaded fastener, and a fastener receiving opening is formed through said web other end.

3. A sheet metal pull tab particularly adapted for attachment to a tearable container portion, said pull tab being of a shallow winged channel cross section and including a web having sides and ends, a narrow upstanding flange extending along the sides and one end of said web and a wing flange extending outwardly from said vvupstanding flange along the sides andthe one end of said web, and an inturned hem along the periphery of said wing flange thereby forming a rigid structural unit, said pull tab being generally rectangular in outline, said web being widened at kthe other end thereof to provide clearance for a beaded fastener with said wing flange being proportionally narrowed, and a fastener receiving opening formed through said web other end.

4. A sheet metal pull tab particularly adapted for attachment to a tearable container portion, said pull tab being of a shallow `winged channel cross section and including a web having Vsides and ends, a narrow upstanding flange extending along the sides .and one end of said web and a wing flange extending outwardly from said upstanding flange along the `sides and the one end of said web, and an ,inturned hem along the periphery of said wing flange thereby forming a rigid structural unit, said hem being disposed entirely between the planes of said web and said wing flange.

5. A sheet metal pull tab particularly adapted for attachment to a tearable container portion, said pull tab lbeing of a shallow winged channel cross section and including a web having sides and ends, a narrow upstanding flange extending along the sides and one end of said web and a wing flange extending outwardly from said upstanding flange along the sides and the one end of said web, and an inturned hem along the periphery of said lwing flange thereby forming a rigid structural unit, said hem being disposed entirely between the planes of said web and said wing flange and extending the full height of said upstanding flange.

References VCited by the Examiner UNITED `STATES PATENTS D. 195,604 6/63 Fraze 58-26 2,750,062 6/56 Satz 215-46 3,066,821 12/62 Conklin 21S-46 3,151,766 10/64 Henchert 220-53 LOUIS G. MANCENE, Primary Examiner. THERON E. CONDON, Examiner.

Claims

1. A SHEET METAL PULL TAB PARTICULARLY ADAPTED FOR ATTACHMENT TO A TEARABLE CONTAINER PORTION, SAID PULL TAP BEING OF A SHALLOW WINGED CHANNEL CROSS SECTION AND INCLUDING A WEB HAVING SIDES AND ENDS, A NARROW UPSTANDING FLANGE EXTENDING ALONG THE SIDES AND ONE END OF SAID WEB AND A WING FLANGE EXTENDING OUTWARDLY FROM SAID UPSTANDING FLANGE ALONG THE SIDES AND THE ONE END OF SAID WEB, AND AN INTURNED HEM ALONG THE PERIPHERY OF SAID WING FLANGE IS UNDERLYING RELATION TO SAID WING FLANGE THEREBY FORMING A RIGID STRUCTURAL UNIT.