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Publication numberUS3255917 A
Publication typeGrant
Publication dateJun 14, 1966
Filing dateSep 9, 1963
Priority dateSep 9, 1963
Publication numberUS 3255917 A, US 3255917A, US-A-3255917, US3255917 A, US3255917A
InventorsFraze Ermal C
Original AssigneeFraze Ermal C
Export CitationBiBTeX, EndNote, RefMan
External Links: USPTO, USPTO Assignment, Espacenet
Container opening device for metallic can ends
US 3255917 A
Abstract  available in
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Claims  available in
Description  (OCR text may contain errors)

E. C. FRAZE June 14, 1966 CONTAINER OPENING DEVICE FOR METALLIC CAN ENDS Filed Sept. 9, 1963 2 Sheets-Sheet June 14, 1966 E. c. FRAZE 3,255,917

CONTAINER OPENING DEVICE FOR METALLIC CAN ENDS Filed Sept. 9, 1963 2 Sheets-Sheet 2 United States Patent 3,255,917 CONTAINER OPENING DEVICE FOR METALLIC CAN ENDS Erma] C. Fraze, 355 W. Stroop R0ad,. Dayton 29, Ohio Filed Sept. 9, 1963, Ser. No. 308,048 11 Claims. (Cl. 220-54) This application isa continuationdn-part of my copending application Serial No. 160,487, filed December 19, 1961, now abandoned.

The invention broadly relates to a metallic can construction and, more particularly, to an improved can opening arrangement of the type wherein the opening device and can are permanently and fixedly associated.

As is we'll known in the art to which the present disclosure pertains, there is usualy provided a cover for a metallic can or container which has incorporated therein a prescored tear strip formed in its surface and extending generally around the periphery thereof immediately adjacent the cover edge. Frequently, the tear strip has a leading end which may be operatively associated with a key to accomplish initial fracture and subsequent removal of the tear strip from the can whereby a portion of the cover is removed. Further, and as well known to those skilled in the art, prescored strip arrangements to the type here under consideration have also been utilized on containers and in other sections thereof such as the can body. For example, many prior art arrangements provide a tear strip extending peripherally around the can whereby the lid and a portion of the side of the can may be removed.

To accomplish strip removal, many prior art arrangements have secured to the leading end of the tear strip a fixedly connected opening key which provides a lever for initiating the tearing action and tfor thereafter removing the entire tear strip. Arrangements of the connected key variety have employed, for example, a weld to provide a fixed connection between the key and the leading end of the tear strip. These early designs of weld connection have used both cold and hot welding techniques. Other modes of fixed connection between the key and the leading end of the tear strip have also been suggested such as, for example, deforming portions of the key and the leading end of the tear strip so that a mechanical interlock may be produced there'between utilizing the deformed portions of the key and can. A desirable feature of weld and mechanical interlock techniques is that can continuity and seal is maintained and content spoilage or contamination is avoided.

In present day manufacture, and depending upon cost and use considerations, particular cans may be manuractured from a variety of metals such as aluminum or steel. Furthermore, and in a given class of metal can construct-ion, the cans, depending upon their ultimate use, are manufactured of varying thicknesses. In all applications, however, it is desirable to leave a substantial thickness of residual metal after scoring, since it is obvious that scoring weakens the can lid. With substantial residual thickness after scoring, can strength is not seriously weakened. However, can opening correspondingly becomes more diflioult.

Asa result of the above-mentioned factors, many users have difficulty in accomplishing can opening, i-t being difiicult for some to apply sufficient force to accomplish initial strip fracture and subsequent tear strip removal. This is particularly true in cans having contents which require the relatively heavier can sections to resist a high internal pressure such as those cans which contain carbonated beverages. In the prescored tear-strip type can opening arrangement, it will be understood that the 3,255,917 Patented June 14, 1966 most difficult manual manipulation is that required to accomplish the intial strip fracture. In this operation, the most applied force is necessary. Thereafter, the removal force applied to the now fractured tear strip tends to concentrate itself at the immediate points of juncture between the tear strip and cover, and this force required to remove the tear strip subsequent to initial fracture is considerably less.

The herein disclosure invention is generally directed to a unique key arrangement which may be connectably associated with a leading end of a tear strip whereby the key functions initially to provide afirst mode of force distribution and concentration for initial tear strip severance and thereafter is operative to provide a means for continuous force application to accomplish complete removal of the tear strip.

Accordingly, the present disclosure comprehends the rather unique arrangement that provides a relatively high initial mechanical advantage to accomplish initial tear strip fracture. Thereafter, the'key functions as a force distributionarrangement to apply the tear strip removal force to the cover.

It will be noted that the present invention is particularly adaptable to that type of key connection illustrated in my copending application Serial No. 280,545, filed May 15, 1963, for a Method of Fabricating a Sheet Metal Joint.

The basic key and tear strip arrangement herecontemplated comprises joined integral portions of a whole device, :one of the portions being what may be termed a base portion or connection portion adapted to act as connecting structure to the related can cover, the other portion which may be termed a lever or handle portion serving initially as a lever offering a high degree of mechanical advantage for initiating the tearing action and subsequently functioning as means to complete the removal of the tear strip. The connection between the first mentioned base portion and the tear strip acts additionally to add support and rigidity to the tear strip during initial cfracture to facilitate the tearing action.

Other features of the disclosed invention relate to the employment of a unique bending axis particularly located at the line of juncture between the base portion and the lever port-ion of the key to facilitate the application of an appropriate initial high mechanical advantage and thereby accomplish relatively easy initial tear strip fracture.

The above-mentioned features and other features and advantages of the invention will be more clearly understood by reference to the following specification and associated drawings, wherein:

FIG. 1 is a top plan view illustrating a typical embodiment of the invention;

FIG. 2 is a fragmentary section taken along line 2-2 of FIG. 1;

FIG. 2a is a section similar to FIG. 2 and showing the 'key section in raised or operative position;

FIG. 3 is a sectional view taken along line 33 of FIG. 1;

FIG. 4 is a sectional view taken along line 4-4 of FIG. 1;

FIG. 5 is a sectional view taken along line 5--5 of FIG. 1;

FIG. 6 is a sectional view taken along line 6-6 of FIG. 1;

FIG. 7 is an enlarged detail fragmentary plan View of the joining area between the connection portion and the lever of the arrangement;

FIG. 8 is a top plan view similar to FIG. 1 illustrating a second embodiment of the invention;

provides the mode of juncture betwen the lid 2. and a cylindrical can body (not shown). The lid 2 is provided with a plurality of score lines 6 and 8 arranged in general alignment with each other and extending peripherally around the lid of said can in a spiral-like form so that removal of the therebetween defined tear strip 10 accomplishes severing of the central portion 12 of the lid 2. The score lines 6 or 8 may be formed in the lid in any convenient manner, as by an appropriate sharp tool, and may be of a depth appropriate to the thickness of the can lid and its ultimate use so that unreasonable weakening of the can lid, which could result in accidental puncture of the lid, would be avoided.

The tear strip 10 has a generally inwardly directed section 14 terminating in a triangularly tipped leading end 16 at some point on the surface 12 of the can lid 2. A manually operable key, indicated generally at 18, is pro vided on the surface 12 of the lid 2 and arranged to overlie the leading end 16 previously mentioned. The key 18, which is a single piece of sheet metal, has a lever portion or handle portion 20 and a base portion or connection portion 22, said portions being integrally formed with each other. The base portion 22 is provided with a generally central aperture 24 (FIG. 2) which is arranged to receive an upwardly extended hollow rivet 26 formed in the leading end 16 of the tear strip 1%). The hollow rivet 26, in the completed assembly, not only projects upwardly through the aperture 24 of the base portion 22, but additionally is appropriately interlocked therewith by virtue of the formation of the bead-like peripheral segment 28 (FIG. 2) formed to overlie the immediately adjacent area of the base portion 22. It will thus be understood that a firm and positive mechanical connection is provided between the leading end 16 of the tear strip and the base portion 22, the connection being preferably made in the manner described in my mentioned copending application.

The lever portion 18 has a lower wall 30 of generally planar form and arranged to abut the surface 12 of the lid 2. It will be understood that the lower wall 30 (FIG. 1) is coplanar with the wall 23 (FIG. 2) of the base section 22. The lever portion 20 further has an elevated finger portion 34 at the free extremity thereof appropriately spaced from the surface 12 of the lid 2. The elevated finger portion 34 provides easy finger access to the underside of the free end of the lever portion section 18.

Additionally, the lever portion 20 is formed with strength ribs 36 and 38 in the form of offsets extending generally-longitudinally of the section to a point where they respectively blend with converging ribs 40 and 42, the latter joining at 44 to provide an apex or point of upwardly convex cross-sectional configuration extending into a recess or notch of the base portion 22. A generally pointed or U-shaped slot, aperture, or cut 48 is formed immediately adjacent the apex 44 and exposes a portion of the underlying tear strip. In this connection, it will be noted that the apex 44 of the lever portion 20 is arranged to immediately overlie the triangular leading end 16 of the tear strip in the final assembly of the key 18 to the lid 2.

Additionally, the lower lid abutting wall 30 of the lever portion 20 is provided with an indentation 50 arranged to extend on both sides of the pointed apex 44 from the respective termination points of the slot 48 to the respective edges of the key. In a preferred embodiment of the invention, the indentation may be formed in the key 18 by any appropriate scoring or coining operation. The indentation 50, therefore, provides a weakened bending axis for the lever portion 20, as will hereinafter appear. Considering the operation of the arrangement, it will be understood that when it is desired to remove the central section 12 from the lid 2, the manipulator simply grasps the outer end 34 of the lever portion 20 and swings the lever portion upward as shown in FIG. 2a, thereby causing a pivotal motion about the indentation 50 which, because of its scored or coined condition, acts as an axis of motion for such upward movement. The apex 44 having a point 52 (FIG. 2a) in physical abutment with the adjacent leading end 16 of the tear strip is caused to rotate with the lever 20 about the score indentation 50 and functions as a short arm of the lever portion, thereby concentrating oper-ating pressure on the tear strip and initially fracturing, as is clearly shown in FIG. 2a, the tip portion 54 of the tear strip. It will be understood that because the lever portion 20 has a relatively long arm on one side of the indentation or bending axis 50 and a relatively short arm on the other side of the indentation 50, the motion just described provides a substantial mechanical advantage to accommodate easy initial fracture of the tip portion 54 of the tear strip. It will also be noted that the base portion 22 not only overlies the tear strip 10 but extends therebeyond on both sides thereof to overlie adjacent area of the can top. By virtue of this arrangement, the base portion 22 lends rigidity to the leading end 16 of the tear strip, thereby increasing the effectiveness of the applied force to induce initial tab fracture. The extended width of the section 22 additionally provides the necessary high strength at the fulcrum connection of the lever portion 20' with the base portion 22.

After initial fracture of the leading end 16 of the tear strip 10, continued motion of the lever portion 20 away from the lid 2 accommodates easy tearing removal of the entire tear strip 10 whereby the central portion 12 of the lid 2 is severed from the can. It will be particularly understood that the connection between the leading end,

of the tear strip and the base portion 22 provided by the hollow rivet 26 does not function initially to directly distribute initial fracture to the tear strip 10. Rather, the positive mechanical connection between the hollow rivet 26 and the base portion 22 acts to reinforce and hold rigid the immediately adjacent portion of the leading end of the tear strip to provide desirable resistance in the general surface area whereby the movement of the apex 44 of the lever 20 tends to concentrate a major part of the available force on the immediately adjacent portion of the tear strip to facilitate initial fracture. This arrangement avoids unreasonably high stress concentration at the connection and generally perpendicular to the surface of the cover, thereby diminishing the possibility of key separation from the cover which has occurred in prior art devices and which renders the can opening arrangement useless. After initial rupture and upon continued motion of the lever portion 20, the severing force is distributed to the strip 10 through the connection between the hollow rivet 26 and the base section 22, it being recalled that the force required for continued severing after nitial rupture is considerably less than that needed for initial fracture.

It will be understood that the sheet metal of the key 18 may have a thickness greater than the lid 2 whereby it resists bending and provides appropriate mechanical strength to accomplish the initial rupture and subsequent severing as above described. In certain applications, it may be desirable to form the key 18 of a material that 1s harder than the lid 2, as, for example, the key 18 may be manufactured from a steel material while the lid 2 may be of aluminum material. Alternately, the apex 44 that accomplishes initial rupture of the tear strip may be appropriately hardened in any conventional manner so as to provide the proper force application for initial tab'rupture.

It will thus be seen that the invention as described provides a novel can opener arrangement comprising joined portions forming integral parts of the whole device arranged to cooperate with a positive mechanical connection to an appropriately scored tear strip to offer a relatively easy initial rupture of the tear strip from the can lid and, thereafter, provide for force distribution from the key through the mechanical connection to the tear strip to accomplish complete lid severing.

An important feature of the described construction is that the metal may be relatively lightly scored for high residual strength and still afltord minimal applied pressure.

FIG. shows the top or lid 60 of a metal can which is scored along a continuous or closed line 62 to provide a tear strip 64 having a tapered leading end 65. A key or sheet metal member, generally designated 66, which may be a one-piece sheet metal stamping, is divided into a base portion 68 and a lever portion 70, With the base portion suitably attached to the leading end 65 of the tear strip. Preferably, but not necessarily, the leading end of the tear strip is attached to the base portion 68 of the key member by means of a hollow rivet 72 as heretofore described, the hollow rivet being formed in the tear strip and being effectively embraced by the base portion of the key member.

In the construction shown, the key member 66 is apertured to form a slot 74 of generally V-shaped configuration with the two legs 75 of the slot diverging towards the side edges of the key member. The cutting of the material to form the slot 74 leaves the base portion and the lever portion of the key member interconnected by two webs at their juncture, and it is contemplated that the material of the two webs will bend to permit the lever portion to be swung outward from the plane of the base portion as heretofore described. Thus, the lever portion 70 functions as a first-class lever fulcrumed at the juncture of the lever portion with the base portion 68, the lever portion having a relatively long operating lever arm and a relatively short working lever arm, the working arm overlapping the leading end 65 of the tear strip.

By virtue of the V-shaped slot 74, the base portion 68 of the key member 66 is formed with a recess 76 in its confronting end and the short lever arm is tapered to an apex 78, with the apex extending into the recess. The V-shaped slot 74 further forms the base portion 68 of the key member 66 with two opposite side portions 80 which flank or straddle the short lever arm and which overlap in length the length of the short lever arm.

To function properly, it is essential that the lever portion 70 of the key member 66 be longitudinally rigid, and for this purpose the sheet material of the lever portion may be embossed or otfset outwardly throughout its length, the lever portion being hollow on its underside.

As shown in section in FIG. 10, the apex 78 of the short lever arm is formed with a radius and is thereby stiffened in a highly effective manner for the application of force against the underlying leading end 65 of the tear strip. Preferably, the opposite free end of the lever portion 78 is curved outwardly to form a rounded finger portion 82 to facilitate manipulation of the lever portion.

An important consideration in the construction of a key member such as described is that any yielding flexure of the base portion of the'key member in reaction to the operation of the lever reduces the effectiveness of the operation of the lever. Thus, if the base portion 68 of the key member yields sufliciently, the key member will be inoperative because lifting of the long lever arm will merely deform the base portion 68 of the key member instead of initiating severance of the tear strip.

The base portion 68 may be longitudinally reinforced in any suitable manner for longitudinal rigidity to prevent undue yielding of the base portion in response to the operation of the lever portion. In the construction shown, the base portion 68 is reinforced by being embossed to form two longitudinal ribs 84 that extend respectively into the two side portions of the base portion 68. In addition, the engagement of the hollow rivet 72 with the base portion 68 of the key member lends rigidity to the central area of the base portion.

The fact that the base portion 68 and the lever portion 70 are separately reinforced for longitudinal rigidity results in the key member 66 having least resistance to flexure at the juncture of the two portions. Preferably,

resistance to flexure at the juncture is further reduced by scoring the two interconnecting webs or metal. Thus, FIG. 9 shows two score lines 85 which are aligned respectively with the axes of the two legs 75 of the slot 74.

It is apparent that the described second. embodiment of the invention functions in the same manner as the first embodiment. When the lever portion 70 of the key member 16 is swung upward, the metal of the key member bends along the two score lines 85, and the apex of the short lever arm swings downward against the leading end 65 of the tear strip 64 to initiate rupture of the tear strip, the leading end of the tear strip being depressed inward out of the plane of the can top 60, as indicated by dotted lines in FIG. 10. It is important to note that the two ribs 84 which lend rigidity to the base portion 68 of the key member 66 flank the short lever arm and overlap in length the length of the short lever arm to extend close to the two score lines 85. The consequence of this rib arrangement and of the stiffening effect of the hollow rivet 72 is that the base portion68 of the key member lies snugly and rigidly flat against the can top 60 and does not flex upward in the region of the fulcrum of the lever. Thus, the full potential of the lever action is realized in the downward thrust of the short lever arm to initiate rupture of the tear strip 64.

My description in specific detail of the selected embodiments of the invention will suggest various changes, substitutions and other departures from. my disclosure within the spirit and scope of the appended claims.

What I claim is:

1. A metallic cover for a container having formed in the cover a plurality of score lines peripherally arranged on the cover and having a tear strip defined by score lines extending generally inwardly of the cover;

the combination of an opening element having a connection portion and a handle portion,

said connection portion overlying the tear strip and extending therebeyond to overlie adjacent areas of the cover,

an aperture in the connection portion receiving a distended-section of the tear strip which extends upwardly through the aperture and is arranged to overlie adjacent areas of the connection portion,

a generally V-shaped opening in the opening element adjacent one edge of the connection portion,

fulcrum means comprising indentations in the opening element and extending from terminal portions of the V-shaped opening to the respective edges of the opening element,

said indentations and said V-shaped opening defining the line of separation between the connection portion and the handle portion,

said handle portion comprising a relatively rigid elongated segment normally in generally faying relationship with the cover,

said handle portion having a force applying tip thereon forming an extension thereof and extending forwardly of said indentation and into said V-shaped opening,

said tip being arranged to immediately overlie the ter- :rninal edge of said tear-strip,

said handle portion and said tip comprising a relatively rigid first-class lever operative to pivot about said indentation and bring said point into pressured engagement with the terminal portion of said tearstrip,

said connection portion being arranged to provide relatively rigid support for said tear strip with adjacent areas of said cover and thereby facilitate the fracture of said tear strip from said cover.

2. In a container having a wall scored to form a tear strip with a leading end, manually operable means to remove the tear strip, comprising:

an elongated member of sheet material positioned facewise on said wall of the container and bendable along a transverse bend line dividing the member into a base portion and a lever portion swingable relative to the base portion by bending action at the bend line,

said member having a single slot of generally U-shaped configuration with both ends of the slot terminating at said bend line and with the bend line extending in both directions laterally from the slot, the middle portion of the slot extending toward said base portion of the member to form an arm of the lever portion pointing oppositely to the direction of the leading end of the tear strip and extending across the bend line,

said base portion of the elongated member being attached to said tear strip at one end thereof with said lever portion overlying said one end of the tear strip whereby manually swinging said lever portion outwardly of the container wall by bending action at said bend line causes said arm of the lever portion to depress said end of the tear strip by lever action to initiate severance of the tear strip.

3. In a container having a wall scored to form a tear strip with a leading end, manually operable means to remove the tear strip, comprising:

elongated means positioned facewise on the container wall,

said elongated means having an aperture and being divided along a transverse line into a base portion and a lever portion with the lever portion swingable at said line, said bend line extending in opposite lateral directions from the aperture,

a short arm of said lever portion pointing oppositely from the leading end of the tear strip and extending across said line,

said base portion being attached facewise to said tear strip with the major portion of the lever portion outside the area of the tear strip with said short arm overlying the tear strip end whereby manually swinging said lever portion outwardly from the container Wall swings said short arm of the lever against the tear strip to initiate severance of the tear strip by lever action.

4. A combination as set forth in claim 3, in which said elongated means is wider than the tear strip and extends laterally beyond both side edges of the tear strip.

5. A combination as set forth in claim 3, in which said lever portion is formed with a longitudinally extending offset with the offset extending to the tip of said short arm for longitudinal stiffness of the lever portion.

6. In a container having a wall scored to form a tear strip with a leading end, manually operable means to remove the tear strip, comprising:

a sheet metal member bendable along a transverse line, the transverse bend line dividing the elongated member into a base portion and a lever portion swingable relative to the base portion by bending action at the bend line,

said base portion of thesheet metal member overlying the leading end of the tear strip and being fixedly attached to the leading end of the tear strip, said lever portion of the sheet metal member being embossed for longitudinal stiffness,

said lever portion overlying the container wall beyond the end of the tear strip and having an outer handle end, said lever portion having an opposite inner end extending beyond said bend line towards the tear strip and pointing oppositely to the direction pointed by the leading end of the tear strip to move downward against the container wall in response to lifting of the handle end of the lever portion thereby to force the leading end of the tear strip out of the plane of the container wall to initiate severance of the leading end of the tear strip by lever action.

7. Manually operable means to remove a tear strip as set forth in claim 6 in which the base portion of the sheet metal member is attached to the leading end of the tear strip by a hollow rivet formed in the material of the tear strip with the hollow rivet holding the base portion facewise against the leading end of the tear strip.

8. In a container having a wall scored to form a tear strip with a leading end, manually operable means to remove the tear strip, comprising:

a one-piece sheet metal member having a connection portion and a handle portion with the handle portion swingable relative to the connection portion by bending of the sheet metal member along a transverse line at the junction of the two portions,

said connection portion overlying the tear strip and extending therebeyond to overlie adjacent areas of the container wall,

an aperture in the connection portion in the plane thereof receiving a distended section of the tear strip which extends through the aperture and overlies adjacent areas of the connection portion,

said handle portion being rigid and normally in generally faying relation with the container wall,

said sheet metal member having a cut therein forming a force-applying tip on the inner end of the handle portion with the handle portion intersecting said transverse line said force-aplying tip extending beyond the transverse line and pointing oppositely to the direction pointed by the leading end of the tear strip,

said handle portion and the tip thereof comprising a relatively rigid first-class lever operative to pivot about said transverse line and bring said tip into pressure engagement with the container wall to force the tear strip portion of the container wall out of the plane of the container wall to initiate severance of the tear strip.

9. In a container having a wall scored to form a tear strip with a leading end, manually operable means to remove the tear strip, comprising:

a one-piece sheet metal member having a transverse cut therein with the opposite ends of the cut spaced inwardly from the side edges of the sheet metal member to divide the sheet metal member into a connection portion and a handle portion with the two portions interconnected by sheet metal webs at the opposite ends of the transverse out,

said two webs being bendable along a transverse line aligned with the transverse cut for swinging movement of the handle portion away from the plane of the connection portion,

said connection portion overlying the tear strip and extending therebeyond to overlie adjacent areas of V the container wall.

an aperture in the connection portion in the plane thereof receiving a distended section of the tear strip which extends through the aperture and overlies adjacent areas of the connection portion,

said handle portion being rigid and normally in generally faying relation with the container wall, said transverse cut forming a tapered force-applying tip on the inner end of the handle portion, said force applying tip pointing oppositely tothe direction pointed by the leading end of the tear strip, 7

said force-applying tip extending beyond said transverse line,

said handle portion and the tapered tip thereof commetal member being formed respectively with longiprising a relatively rigid first-class lever operative tudinal ribs for longitudinal rigidity to resist yieldto pivot about said transverse line and bring said ing fiexure of the base portion in reaction to the tip into pressure engagement with the container Wall operation of the lever portion, to force the tear strip portion of thecontainer out said lever portion of the sheet metal member being of the plane of the container wall to initiate severcentrally longitudinally reinforced for rigidity ance of the tear strip. throughout its length, 10. In a container adapted for easy opening, the comthe base portion of the sheet metal member being atbination of: tached to the leading end of the tear strip by means scoring in the Wall of the container forming a tear 10 including aholloW rivet formed in the tear strip with strip having a leading end; and the base portion of the sheet metal member emaone-piece sheet metal member divided into a base porbracing the hollow rivet and With the rivet lending tion and a lever portion having a long lever arm and rigidity to the base portion of the sheet metal mema short lever arm, the base portion overlying the leadber. ing end of the tear strip and being attached thereto, 15 11. A combination as set forth in claim 10, in which the major portion of the lever portion being outsaid recess in the base portion of the key member and side the area of the tear strip with the short lever said apex of the short lever arm are both formed-by a arm overlying the leading end of the tear strip, the generally V-shaped slot in the key member, the slot havbase portion of the sheet metal member being cut ing two opposite divergent portions; and away to form a recess confronting the short lever 20 in which said juncture is structurally weakened on the arm and the short lever arm being tapered to form an apex extending into the recess with opposite side portions of the base portion of the sheet metal memopposite sides of the key member along lines in alignment with the two divergent portions respectively of the slot.

ber flanking the apex and overlapping in length the length of the short lever arm, said sheet metal mem- 25 ber having least resistance to fiexure at the juncture between the base portion and the lever portion for bending action at the juncture to permit the lever portion to function as a first-class lever fulcrumed at the juncture for application of lifting force to the 3 long lever arm to cause the short lever arm to initiate rupture of the tear strip by depression of the leading end of the tear strip,

said side portions of the base portion of the sheet References Cited by the Examiner UNITED STATES PATENTS 661,570 11/1900 WitkOWSki 220-38 1,856,543 5/1932 Ericsson 220--48 THERON E. CONDON, Primary Examiner.

LOUIS G. MANCENE, GEORGE E. LOWRANCE,

Assistant Examiners.

Patent Citations
Cited PatentFiling datePublication dateApplicantTitle
US661570 *Jan 8, 1900Nov 13, 1900Louis C WitkowskiCan-opener.
US1856543 *May 5, 1930May 3, 1932Lambert Ericsson GustafOpening device for sheet-metal cans and boxes
Referenced by
Citing PatentFiling datePublication dateApplicantTitle
US8844761Aug 10, 2012Sep 30, 2014Daniel A. ZabaletaResealable beverage containers and methods of making same
EP0079294A1 *Nov 2, 1982May 18, 1983CebalDevice to fix a pull tab on a wall
Classifications
U.S. Classification220/273, D09/438
Cooperative ClassificationB65D17/165, B65D17/163
European ClassificationB65D17/16B2, B65D17/16B1