US3204812A

US3204812A - Plastic pull tab to metal tear strip assembly

Info

Publication number: US3204812A
Application number: US289068A
Authority: US
Inventors: Henchert John
Original assignee: Continental Can Co Inc
Current assignee: Continental Can Co Inc
Priority date: 1961-02-10
Filing date: 1963-06-19
Publication date: 1965-09-07
Anticipated expiration: 1982-09-07

Description

J. HENCHERT 3,204,812

PLASTIC PULL TAB TO METAL TEAR STRIP ASSEMBLY Sept. 7, 1965 Original Filed Feb. 10. 1961 INVENTOR JQHM HEMCHEIZT BY 8' ATTORNEYS United States Patent 3,204,812 PLASTIC PULL TAB T0 METAL TEAR STRIP ASSEMBLY John I-Ienchert, Oak Park, Ill., assignor to Continental Can Company Inc, New York, N.Y., a corporation of New York Original application Feb. 10, 1961, Ser. No. 88,473, now Patent No. 3,151,766, dated Oct. 6, 1964. Divided and this application June 19, 1963, Ser. No. 289,068

2 Ciaims. (Cl. 22054) This application is a division of my copending application Serial No. 88,473, filed February 10, 1961, now Patent No. 3,151,766, granted October 6, 1964.

This invention relates in general to new and useful improvements in means for opening containers, such as cans, and more particularly is directed to a novel tear strip arrangement for containers including metal can ends wherein a container may be opened by merely grasping a pull tab attached to a tear strip and removing the tear strip to thereby remove a panel of the container.

One of the primary objects of this invention is to provide a novel tear strip and pull tab combination wherein the pull tab is firmly anchored to one end of the tear strip and is of a greater Width than the tear strip whereby the pull tab rests upon the associated container member on opposite sides of the tear strip to reinforce the tear strip at its starting end to eliminate the accidental rupture of the container member at the starting end of the tear strip.

Another object of this invention is to provide a novel tear strip and pull tab arrangement wherein the pull tab is provided with an end which is merely passed through an opening in the starting end of the tear strip and is thus interlocked with the tear strip, with the mechanical connect-ion between the tear strip and the pull tab being suificiently great to prevent the accidental removal of the pull tab from the tear strip during a tear strip removal operation.

This invention also proposes to provide means to facilitate the starting of the tearing of a tear strip from the adjacent metal whereby the tear strip is provided with a generally semi-circular end portion which is scored more deeply than side edge portions of the tear strip, whereby a lesser starting force is required to rupture the tear strip along the score lines.

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 drawings.

In the drawings:

FIGURE 1 is a perspective view of an upper portion of a can having a metal can end which is provided with a tear strip and pull tab in accordance with this invention.

FIGURE 2 is a perspective view similar to FIGURE 1 and shows the tear strip partially removed.

FIGURE 3 is an enlarged fragmentary prospective view showing further the general details of the tear strip and pull tab combination.

FIGURE 4 is an enlarged fragmentary vertical sectional view taken along the line 44 of FIGURE 3, and shows the specific details of the connection between the pull tab and the tear strip.

FIGURE 5 is an enlarged fragmentary transverse vertical sectional view taken along the line 55 of FIGURE 3 and shows further the details of the connection between the pull tab and tear strip, including the fact that the pull tab overlies the metal can end on opposite sides of the tear strip to prevent the accidental rupturing of the can end along the outline of the tear strip by a downward pressure.

FIGURE 6 is a fragmentary plan view showing the 3,204,812 Patented Sept. 7, 1965 general outline of the tea-r strip at the starting end thereof and the formation of the score lines defining the same.

FIGURE 7 is an enlarged fragmentary vertical sectional view taken along the line 7-7 of FIGURE 6, and shows the specific arrangement of the scores in the various portions of the metal can end along the outline of the tear strip.

Reference is first made to FIGURES 1, 2 and 3, wherein there is illustrated a conventional type of can which is generally referred to by the numeral 20, and which includes a can body 21 and a can end 22. The can end 22 is preferably formed of a light guage metal, and it is desirable that the metal be easily ruptura'ble. As a result, normally the can end 22 will be formed of aluminum, although the usual metals employed in the making of the can ends may be utilized. The can end 22 is secured to the can body 21 by a conventional seam 23. The can 20 is illustrated and described only to set forth one environment of the invention. The present invention is not restricted to cans, but may be used in all types of containers, etc., where it is desired to remove a portion thereof without utilizing any opening equipment, such as a can opener in the case of a can.

Reference is now made to FIGURE 3 in particular, wherein the can end 22 is illustrated as having a circumferential tear strip 24 which is defined by a pair of

score lines

25, 26 with the score line 25 being disposed outermost and being disposed adjacent the seam 23 so that when the tear strip 24 is removed, substantially the entire can end 22 within the seam 23 will be removed. The

score lines

25, 26 are disposed generally in concentric relation for the most part of their lengths and the score line 26 generally defines an inner panel 27.

A pull tab, generally referred to by the numeral 28, is secured to the starting end of the tear strip 24. The pull tab, as is best shown in FIGURES 4 and 5, is formed of a resilient deformable plastic.

The starting end of the tear strip 24 is provided with an opening 29 therethrough which is, in part, defined by a downwardly and inwardly sloping annular flange 30. The pull tab 28 is formed with an integral plug 31 which is recessed, as at 32, to be hollow or of a tubular configuration. The plug 31 extends through the opening 29 defined by the flange 30 and thus secures the pull tab 28 to the tear strip 24.

The lower portion of the plug 31 is provided with an annular rib 33 which has an upwardly flared lower portion 34 and an inwardly tapering upper portion defining shoulder 35. The flaring of the lower portion 34 facilitataes the insertion of the plug 31 through the opening 29. The terminal edge of the flange 30 rests upon the shoulder 35 and prevents the accidental withdrawal of the plug through the tear strip 24.

It will be readily apparent that the pull tab 28 may be connected to the tear strip 24 by simply pressing the plug portion 31 through the opening 29 until the annular ri'b 33 snaps beneath the lower edge of the flange 30. It is also to be noted that the pull tab 28 is of a greater width than the tear strip 24 whereby the main portion of the pull tab 28 serves to support the starting end of the tear strip 24 against accidental inward displacement by a force exerted on the starting end of the tear strip 24.

The end portion of the pull tab 28 remote from the tear strip 24 is provided with an upper transverse rib 36 and a lower transverse rib 37 to facilitate the grasping of the pull tab 28 and exerting a tear strip tearing and removal force thereon. The

transverse ribs

36 and 37 are preferably in alignment with one another, as is clearly shown in FIGURE 4. It is to be noted that the rib 37 is of a thickness equal to the spacing between the main portion of the pull tab 28 and the can end 22 whereby in the normal at rest position of the pull tab 28, the rib 37 rests upon the can end.

It is to be understood that the plug portion 31 of the pull tab 29 is compressively engaged with the flange 30 surrounding the opening 29 so that a seal i maintained between the plug portion 31 and the flange 30 at all times, .thus providing for the efiective sealing of the tear strip 24 although the opening 29 has been formed therein. The connection is of a nature wherein the can 20 is suitable for beverages packaged under pressure, etc.

Reference is now made to FIGURES 6 and 7, wherein .the details of the score lines-defining the various tear strips at the starting end of each tear strip, are shown. .For identification purposes only, the partial can end illustrated in FIGURE 6 will 'be considered to be the can end 22, and the tear strip, the tear strip 24. As previously described, the tear strip 24 is defined by a pair of

score lines

25, 26. As is best illustrated in FIGURE 7, these

score lines

25, 26 are relatively shallow. The

score lines

25 and 26 will preferably be of a depth so that the remaining metal to be torn in the removal of the tear strip 24 will have a thickness of 0.003 inch. The ends of the

score lines

25, 26 are connected together by a generally semi-circular score line 102 which has a greater base width and is of a greater depth, as is best illustrated in FIGURES 6 and 7. The depth of the score line 102 will be such that in most instances, the remaining thickness of metal tube torn will range between 0.001 inch and 0.0015 inch. By making the score line 102 much deeper than the

score lines

25, 26, it will be readily apparent .that a sharp upward pull on the starting end of the tear strip 24 by means of the pull tab 28 will result in the rupturing of the metal of the can-end 22 along the score line 102. Once the initial rupturing has been accomplished, the tear strip 24 may be removed 'by continuously exerting an upward pull thereon with the tear strip 24 being torn from the can end 22 along the

tear lines

25, 26. The advantage of the relatively deep score line 102 coupled with the supporting feature of the individual pull tab is obvious. Applicant has made the initially torn portion of the can end of sufficient weakness to facilitate the ease of tearing the starting end of the tear strip therefrom. On the other hand, by making each pull tab of a suificient width to engage the can end outwardly of the tear strip, the tear strip is prevented from deflecting inwardly due to any accidental force exerted thereon, whereby the can 20 would be opened prematurely.

From the foregoing, it will be seen that novel and advantageous provision has been made for carrying out the desired end. However, attention is again directed to the fact that variations may be made in the examples of the invention disclosed herein without departing from the spirit and scope of the invention, as defined in the appended claims.

I claim:

1. A tear strip assembly comprising a panelhaving a score line therein defining a removable tear strip having a starting end, that portion of said soore line defining said starting end being of a greater 'depth than adjacent portions of said score line to facilitate the initial rupture of said panel, and a pull tab overlying and connected to said tear strip starting end, said pull tab being Wider than the underlying portion of said tear strip and resting on said panel outwardly of said tear strip to prevent accidental rupturing of said panel along said greater depth score line portion by inward displacement of said tear strip starting end, said tear strip having an opening therethrough and said pull tab having a plug portion extending through said tear strip opening and locking behind said tear strip to both directly seal said opening and secure said pull tab to said tear strip, said tear strip opening being defined by a downwardly directed flange on said plug portion having a lower part engaged behind said flange, said plug portion being upwardly flared beneath said shoulder and formed of a resilient deformable plastic to facilitate the insertion of said plug portion through the tear strip opening.

2. The tear strip assembly of claim 1 wherein said pull tab is in the form of an elongated strip having a thick attaching portion and .a thinner grip portion, said grip portion having transverse ri'bs extending thereacross to facilitate gripping thereof.

References Cited by the Examiner UNITED STATES PATENTS 2,029,329 2/ 36 Ljungstrom et a1 22 052 X 2,224,296 12/40 Hoffman.

2,978, 4/61 Walsh.

THERON E. CONDON, Primary Examiner.

Claims

1. A TEAR STRIP ASSEMBLY COMPRISING A PANEL HAVING A SCORE LINE THEREIN DEFINING A REMOVABLE TEAR STRIP HAVING A STARTING END, THAT PORTION OF SAID SCORE LINE DEFINING SAID STARTING END BEING OF A GREATER DEPTH THAN ADJACENT PORTIONS OF SAID SCORE LINE TO FACILITATE THE INITIAL RUPTURE OF SAID PANEL, AND A PULL TAB OVERLYING AND CONNECTED TO SAID TEAR STRIP STARTING END, SAID PULL TAB BEING WIDER THAN THE UNDERLYING PORTION OF SAID TEAR STRIP AND RESTING ON SAID PANEL OUTWARDLY OF SAID TEAR STRIP TO PREVENT ACCIDENTAL RUPTURING OF SAID PANEL ALONG SAID GREATER DEPTH SCORE LINE PORTION BY INWARD DISPACEMENT OF SAID TEAR STRIP STARTING END, SAID TEAR STRIP HAVING AN OPENING THERETHROUGH AND SAID PULL TAB HAVING A PLUR PORTION EXTENDING THROUGH SAID TEAR STRIP OPENING AND LOCKING BEHIND SAID TEAR STRIP TO BOTH DIRECTLY SEAL SAID OPENING AND SECURE SAID PULL TAB TO SAID TEAR STRIP, SAID TEAR STRIP OPENING BEING DEFINED BY A DOWNWARDLY DIRECTED FLANGE ON SAID PLUG PORTION HAVING A LOWER PART ENGAGED BEHIND SAID FLANGE, SAID PLUG PORTION BEING UPWARDLY FLARED BENEATH SAID SHOULDER AND FORMED OF A RESILIENT DEFORMABLE PLASTIC TO FACILITATE THE INSERTION OF SAID PLUR PORTION THROUGH THE TEAR STRIP OPENING.