US3186581A

US3186581A - Container

Info

Publication number: US3186581A
Application number: US246029A
Authority: US
Inventors: Schneider Alden James; Taylor William Edward; Eckman George Ernest
Original assignee: American Can Co
Current assignee: Primerica Inc
Priority date: 1962-12-20
Filing date: 1962-12-20
Publication date: 1965-06-01
Anticipated expiration: 1982-06-01
Also published as: DE1452539A1; BE641526A; ES294682A1; DK111346B; GB1071746A; CH417375A

Description

June 1, i965 A. J. scHNEmER ETAL,

CONTAINER Filed nec. zo, 1962 J iff ff ff? United States The present invention relates to containers,v and has particular reference to a hermetically sealed sheet metal reclosure can which may beopened by the simple process of peeling fr om its bodyV a circumferentially extending pull tape to uncover a circumferential slit which partly separates the upper portion of the can from its bottom portion, and then bending the upper portion upwardly to break-the body along a score line to complete its separation.

inV recentV years, great emphasis has been given to the development of consumer'packages which have added appeal to theconsumer because of special consumer convenience features whichthey offer. One of the most highly prized of such features is ease of opening. However, although it is comparatively simple to embody easy opening-features in containers made of soft, easily tearable materials such as paper and plastic, it is much more diicult in the case of the sturdier sheet metal cans which are closed by means of tamperproof, double seamed end members, and such cans have thus heretofore usually required the use of an opening tool such as an opening key or a can opener to effect the opening operation.

f The present invention solves this problem by providing a hermetically sealed can wherein the can body is provided with a precut circumferential slit which extends around the major portion of the can body just below its upper end seam and is sealed by an external sealing tape which can be easily stripped from the body to uncover the slit and'permit ready detachment of the upper portion of the can.

To reinforce the slit areaof the body against inadvertent breakthrough or displacement; of the abutting slit edges, a suitable internal reinforcement in the form of a separate or integral collar is disposed inwardly of the slit. In addition to its reinforcing function, the collar provides a. seat for'the detached upper portion of the can so that it can be used as a reclosure after the initial opening of' the can. 4

In order to -permit economical manufacture of the instant can, the slit is not extended completely around the body, but is terminated short of each side lof the side seam area so that the body blank remains at all times duringits manufacture a unitary, self-sustaining member which can be handled by thehigh speed automatic equip-` ment on which cans must bemade in order to be economically competitive with other types of containers. The unslit poriton-offthe body `between the ends of the slit is, however, scored so that when the tape is removed and the upper portion of the body hinged upwardly around the scored body portion by the ultimate consumer, the flexing of the scored metal causes the body .to break along the score line, thus completing the severance of the upper can portion and permitting it to be completely removed from the lower portion of the can to provide a convenient reclosure. i

An object ofthe invention, therefore, is the provision Y of` an easily opened, hermetically sealed reclosure can.

Another object of the invention isthe provision of an easily opened can which can be made on highspeed, automatic equipment.

Yet another object` is the provision of a can which may be'easily opened merely by the removal therefrom of an easily peelable sealing tape and a subsequent upward hinging of the body along a short breakable hinge section.

Numerous other objects and advantages of the invenf tion will be apparent as it is better understood from the following description, which, taken iny connection with the accompanying drawings, discloses a preferred embodiment thereof.

Referring to the drawings:

FIGURE l is an elevational View of a can embodying p the concepts of the instant invention; Y FIG. 2 is an enlarged fragmentary View of an upper portion of the can of FIG. l, the view showing the side seam area of the can with the sealing tape partially peeled from the can body to initiate the can opening operation; FIG. 3 is a plan view of the exterior surface of a flat blank for making the body of the can shown in FIG. l;

FIG. 4 is a vertical section, on an enlarged scale, taken substantially along the line 4-4 in FIG. 2;

FIG. 5 is a sectional view taken substantially along the line 5-5 in FIG. l;

FIG. 6 is a sectional view taken substantially along the line 6 6 in FIG. 3 and FIG. 7 is a view similar to FIG. 4 but illustrating a modified form of the invention.

As a preferred and exemplary embodiment of the instant invention, the drawingsillustrate a sheet metal can which is formed with a tubular, preferably cylindrical body 10 which is formed from a flat, single-piece, sheet metal blank 12 (see FIG. 3) which has its opposite side edge portions 14, t6 suitably notched and slit to form hook portions 1S, 20 so that when the blank is bent to tubular form to form the body 10, the edge portions 14, 16 may be joined in a soldered side seam 22. whereinv the upper and

lower portions

24, 26 comprise lap sections and the intermediate portion 28 comprises a lock section wherein the hooks 1S, 20 are reversely folded and interlocked with each other (see FIG. l). i

The opposite ends of the body 10.are sealed by irnperforate top and bottom end members 30, 32, respectively, which are secured thereto in hermetic, compound lined double seams 34.

The body 10 closely below the top double seam 34 is completely cut through to provide a circumferential slit 36 which extends around the major portion of the body and terminates just short of both sides of the upper lap portion 24 of the soldered side seam 22, as best seen in FIGS. 1 and 2. Between the separated ends of the slit 36, the sheet metal of the body 10, including both layers of the lap seam portion 24, is partially cut through to provide a score line 38 which connects the ends'of the slit 36.

The slit 36 is covered over and sealed against leakage by a thin, narrow tape 40 which is bonded to the outside`r surface, of the can body 10 and extends circumferentially around the can and also terminates short of either side of the side seam 22, so that it does not interfere with the side seam forming operations. Y Y

The tape 40 preferably comprises an external layer of aluminum foil 42 and a klayer of a thermoplastic resin 44 which is heat Sealed to the can body 10 to create a hermetic, liquid proof seal around the slit 36.-

vOne end of the tape 4t) is not bonded to the body 10, but is'doubled back on itself to form a pull tab 46, the

, occurs, the tape will not peel cleanly resin layers inthe pull tab being heat4 sealed together to has the folvDensity, .923.V

Tensile strength 1720 psi. Tensile impact 1500p.s.i. vYield strength V 1345 psi.

Elongation 526% VRigidity 1.5 X 104 psi` Hardness (Shore C) 80.

Peel tests with this ethyleneacrylic acid copolymer;

minus 0.5%) by weight, based on copolymer weight,

vreclosure which, when repositioned in frictional engagementrwith the-collar 50protects the unused portionof wherein two strips of tin plate, each wide, which are adhered to each' other by an interposed layer of this of l inch .per minute and a temperature ot 77 F. indicate a peel Strength ofabout 2.4 lbs. per 3A lineal inch.

This ethylenefacrylic acid copolymer preterabl f is ero' inea molten state.

of aluminumtoil andto then cut the tape 49 from the.'

resultant foil-resin lamination. a tape 40 of suti'icient strength and flexibility to ymeet the Y copolymerare pulled .apart at an 180 angle at a speed `truded directlyV onto the aluminum foil Vlayer-42 while` The mostl practical way of accomplishing this is to eXtrude the resin onto a large web It has Ybeen found that`Y normal requirements ofthe instant container is producedV I when the foil layer $2 is vabout 0.093 inch `thick and the resin layer 44 :is aboutl mil thick. These thicknesses e canot course be varied to meet specific can requirements.

The tape 40 is preferably applied to the body blank` 11.2` while the latter is in the fiat, as seeniin FIG.' 3," so

that itk forms a patch over the slit '35 which has the keiect of'reinforcing the slitrblank and thus permitting it to be handled by automatic can making'equipmentin much the same manner asis an unslit'blank. This application of the tape may be easily effected by heating, the body. blank 12 to a temperature of'about 325V F. to 345 Ff andpressing they tape against the blank'under moderate pressure. It is desirable to avoid overheating the blank, lest` this result in degradation of the resin 44. it` this but will'leave a residue on the blank.

It will beQunderstood that although theabove described ethylene-acrylic acid lcopolymer is well suited for use as NVA ' sound which is so reassuring `tothe consumer.

the thermoplastic resin V4/tof the instant container, it

is' by no means the only material suitable for this purpose; and other compositions having generally comparable sealing fand peeling characteristics may be substituted.

ln 'order to support the can body itl inwardly of the 1 slit 36 and thus prevent inadvertent relative displacement between the can body portions above and below the slit during shipment and storage ofthe filled, sealed can and during the can manufacturing operations wherein endwise compressive forces are exerted on the body,r such as the die Hanging operation and theV end searningV operationshthe body it) is provided with an interior collary which 'ehg'age's'tightly within Vthe body inwardly of the slit 36. -The collar may eitherbe a separate collar 5t) (see FIG. 4) which is formed with an upper, inwardly curled edge 52 and has its bottom edge portion 54 expanded outwardlyinto a groove 56 formed in thebody 1o to securelylock the collar in place, oran integral folded collar 58 which is created by a doublereverse foldingl of the body k1) in the slit area so that two layers of the body 1t? tlie inwardly of the slit 36 to form the collar 5S.` Reference is had to United States Letters A'Patent' 1,615,930 issued to whuums on February 1, 1927 on n dell Can and Method of Forming or further details'regardingV this folded wallconstruction.

In addition to its reenforcing function, Vthe collar provides a reclosure seat for thelrcan reclosurev which is created inthe can opening operation, lasar/illnowbe l described; Y

When the consumer, desires to open the sealed can, .he

grasps the tree'pull `tab 46 and pulls radially outwardly on it, thus peeling the tape` dd'from. the can body itl UntilV it is completely ydetached.'` The'upper portion of the can 'which isdisposedabove the slit 36 is then movedE upwardly in, a hinginglaction inl which the -score line 3S Vserves as the fulcrunr The resultantbending or kflexing ot vthe scoredmetal offthe .score line 38 results in the breaking of the body along thejscore line 3S thereby completing the Aseverance of the;` upperV portion ot Vthecan from Ythe lower `portion.andpermitting its complete'detachment therefrom` for use "asa separate been found that the heated-resin ddfrequen'tly flows to agreaterorlesser extent'into the slito Vduring the 'heat sealing operation and `thereby *seals it sothat this gas cannotescape from the .caniuntil the` upper portion of the can is hinged upwardly. This latter bringing action permits so Ymuch of the ygas to escape .that the character istic hissingk sound which results from'theescape of trapped gas throughY a comparatively small opening is .absent', thereby leading some consumers to mistakenly assume that the can has not beenrhermetically sealed.,

In'orderto prevent'this'a small perforated opening or orifice 6% is provided'in the can body l@ at the juncture ofthe siit 36" and score line 38 onthe pull tab side of the yside seam 22.1 Thus, when the pull tab d6 of thetape is grasped land pulled to strip the tape'f from the body i2., theopening 6), is uncovered almost immediately and the gas in the can escapes Vwith the characteristic 'hissing This occurs :because of the fact that the collarl does not lie in sufficiently tight or intimate contactwith the outwardly disposed body Vportion'to create a hermetic sealing relationship therebetween, and ;consequentlythe" gas is enabled to tlowin the minute space between the collar and the can body'and Vreach the'opening 6! in .suiiicient quan-V tity to ycreate the ,desired hissingrsound. i o It is thought that the inventionfandA many of its attendant advantages will be understood from the foregoing description and itrwill be apparentfthat various changesl maybe maderin the form, construction, and arrangement of the parts wit-hout departing Vfromthe spirit and scope of the invention or sacrificing all 'of its'material advan- Ytages,"the Vform hereinbeforesdescribed beingrmerely a preferredv embodiment thereof. Y We claim:V 1. An easily openedreclosure can, comprising in .cornbination: Y

a tubular sheet metalpb'ody having itsV edgesV seamed together in a longitudinal side seam, Y a circumferential slit Vformed in said body adjacent one end andV extending around amajor'portion thereof, said sl-it terminating closely' Yadjacent both sides `of said side seam, Y v peelabletape of metallicfoil ,covering and sealing Y said slit andbeing bonded to the` adjacent portions of said ,can body bya thermoplastic resin' adhesive or low peel resistance, and E Y a collar disposed Within said can body adjacent said slit for suporting said can body in the area thereof on both sides of said slit, said collar extending 1ongitudinally beyond one portion of said can body after it has' been opened along said slit and being engageable with another portion of said can body beyond said slit to provide a reclosure seat therefor.

2. The can of claim 1 wherein a score line is formed in said can body and extends from one end of said slit to the other end thereof, said score line extending conipletely through all of the layers of said can body in said side seam thereof to provide for complete separation of the portions of said can body on opposite sides of said slit.

3. The can of claim 1 wherein said tape is provided with an unbonded end portion which is folded back on itself to form a pull tab of double thickness.

said tape.

References Cited bythe Examiner UNITED STATES PATENTS 6/91 Quentell 220-5 4 7/ 19 Tomlinson et al. 220--5 3 11/54 Henchert 220-54 4/ 5 6 Andersen 220-54 1/ 5 7 Cheeley 229-51 9/57 Gaines 220-54 7/ 63 Kenney 220-53 FOREIGN PATENTS 1/ 6 1 Canada.

THERON E. CONDON, Primary Examiner.

Claims

1. AN EASILY OPENED RECLOSURE CAN, COMPRISING IN COMBINATION: A TUBULAR SHEET METAL BODY ITS EDGES SEAMED TOGETHER IN A LONGITUDINAL SIDE SEAM, A CIRCUMFERENTIAL SLIT FORMED IN SAID BODY ADJACENT ONE END AND EXTENDING AROUND A MAJOR PORTION THEREOF, SAID SLIT TERMINATING CLOSELY ADJACENT BOTH SIDES OF SAID SIDE SEAM,