US3247997A

US3247997A - Easy opening pull tab can end with wide tear strip

Info

Publication number: US3247997A
Application number: US335560A
Authority: US
Inventors: John S Bozek
Original assignee: Continental Can Co Inc
Current assignee: Continental Can Co Inc
Priority date: 1963-06-28
Filing date: 1964-01-03
Publication date: 1966-04-26
Anticipated expiration: 1983-04-26
Also published as: US3195768A; GB1037336A; BE656798A; NL6407360A; DK116844B; DE1266655B

Description

April 26, 1966 J. s. BOZEK 3,247,997

EASY OPENING PULL TAB CAN END WITH WIDE TEAR STRIP $16.3 Jenn S. B Z g3 April 26, 1966 J. 5. BOZEK 3,247,997

EASY OPENING PULL TAB CAN END WITH WIDE TEAR STRIP Filed Jan. 3, 1964 3 Sheets-Sheet 2 FIG. ll JOHN 5025K 7 ,F L gm-1 ATTORNEYS April 6, 1966 J. 5. BOZEK 3,247,997

EASY OPENING PULL TAB CAN END WITH WIDE TEAR STRIP Filed Jan. 5, 1964 "f7 1 6. INVENTOR JOHN S. BozEK United States Patent 3,247,997 EASY OPENING PULL TAB CAN END WITH WIDE TEAR STRIP John S. Eezek, Chicago, 111., assignor to Continental Can gonggpany, Inn, New York, N,Y., a corporation of New Filed Jan. 3, 1964, Ser. No. 335,560 2 Claims. ((31. 220-54) This application is a continuation-in-part of Serial No. 291,415, filed June 28, 1963, now Patent No. 3,195,768.

This invention relates in general to new and useful improvements in the manufacture of containers, and more specifically relates to a container end which is particularly adapted for opening without the use of any tools or open: ing elements other than those which are parts of the container.

In the past, it has been necessary for one to have a special opener in order to open containers of the type wherein products are dispensed through the ends of the containers. Recently, there have been developed container ends with tear strips defined therein by weakening lines and the tear strips have attached thereto pull tabs to facilitate the tearing of the tear strips along the weakening lines. Such con-tainer ends have five major deficiencies. The deficiency producing the problem from the standpoint of maintaining a seal is that after the container ends have been weakened to define the tear strips,

any shock imparted to the container, particularly to the container end, may cause rupture of the container end along one of the weakening lines. On the other hand, it the weakening lines are made too shallow, then the tear strips cannot be removed with the desired ease.

Another problem encountered is the economical attachment of a pull tab to the tear strip in a manner wherein a seal is maintained between the pull tab and the tear strip. The third problem has been in the formation of a proper pull tab which is small enough to be confined within the normal recessed end of a container, such as a can, and at the same time be of sutficient strength and size to be effectively gripped in a manner necessary to effect the tearing of the tear strip from the container end.

The other two deficiencies of present container ends relate to the removal of a major portion of the end panel in the opening thereof. The presently available can ends have a relatively narrow tear strip which has insuflicient cross section to maintain its shape as it is torn from the container end. As a result, the tear strip assumes an almost straight line relationship with the result that as one pulls on the tear strip, ones hand becomes quite distant from the can end and towards the end'of the tear strip removing operation, it becomes extremely diflEicult to continue to pull the tear strip. In fact, often it has become the normal reaction of people to release the pull tab and to grip an intermediate portion of the tear strip close to the can end and thus continue the tear strip removing operation. Due to the fact that the removed tear strip has fine, yet very sharp burrs along the edges thereof, any relative moving of ones hand with respect to the tear strip in this new position results in the cutting of ones fingers.

The fifth major deficiency of presently available can ends of the type to which this invention relates is that the relationship of the tear strip with respect to the end panel is such that as the tear strip approaches its point of detachment from the can end, that portion of the end panel which is attached to the tear strip for removal therewith has a tendency to pivot about the last point of attachment of the tear strip to the can end and to dip down into the product contained within the can. Then as the tear strip is finally torn from the can end, due partially to the springiness of the metal and partially to the inertia of the tearing operation, the removed portion of the end panel moves towards the person opening the can and the product which is disposed on the removed portion of the end panel is splashed upon the person opening the can. 7

V In view of the foregoing, it is the primary object of this invention to provide a container and which has a peripherally extending tear strip with the tear strip being defined by an inner weakening line and an outer weakening line, the material of the container end adjacent the inner weakening line being reinforced by offsetting the container end immediately adjacent the inner weakening line and the material of the container. end adjacent the outer weakening line being similarly reinforced by the offsetting of the material of the container end.

Another object of this invention is to provide a container end of the easy opening type, which container end includes a peripheral tear strip defined by weakening lines, the tear strip being relatively wide as compared to normal tear strips, and being defined by an outer weakening line and an inner weakening line, and the container end being offset adjacent each of the weakening lines throughout a major portion of the extent thereof to effect a reinforcing of the can end immediately adjacent the weakening lines so as to greatly reduce and, in most instances, eliminate the possibility of an accidental rupture of the container end along one of the weakening lines due to impact caused by rough handling during the normal shipment and storage of the container.

Still another object of this invention is to provide a novel container end which is circular in outline and which has a wide tear strip extending about the circumference thereof and being defined by weakening lines, the container end having an inwardly projecting rib surrounding an outer one of the weakening lines to reinforce the container end immediately adjacent the outer weakening line, and the central portion of the container end being inwardly recessed immediately adjacent the inner one of the weakening lines, the central recessed portion being generally kidney shaped in outline and serving to provide for the reinforcement of the inner weakening line throughout the extent thereof.

Afurt-her object of this invention is to'provide a con-- tainer end of the easy opening type wherein the container end is provided with a peripherally extending tear strip which is defined by weakening lines which include an outer weakening line, an inner weakening line, and an intermediate starting weakening-line joining together the inner and outer weakening lines, the starting weakening line being the deepest of the three weakening lines, and the inner weakening line being the shallowest of the three whereby opening of the container end is facilitated while-the accidental rupture of the container end along one of the weak ening lines is, for all practical purposes, prevented.

Another object of this invention is to provide a container end of the typeset .forth in the above object wherein the outer weakening line, adjacent its outer terminal end thereof, is for a short distance decreased in height after which it again increases for the purpose of momentarily slowing down the tearing operation whereby at the time the tear strip and the associated portion of the end panel are removed, the tearing operation is relatively slow and there is a minimum tendency of the removed portion of the end panel to quickly advance towards the person opening the container, thereby eliminating any possibility of splashing any product which would norm-ally adhere to the underside of the end panel, onto the person opening the container.

A still further object of this invention is to provide a novel container end which includes a tear strip extending generally about the periphery thereof and the tear strip being in part defined by an inner weakening line, a central portion of the container end being inwardly off set adjacent to the inner weakening line to reinforce the container end adjacent the inner weakening line, and a Another object of this invention is to provide a novel plastic pull tab for use with a' tear strip of a container end, the pull tab including an elongated body which is provided at one end thereof with a tubular plug portion,

adapted to be snapped through a flanged opening in a tear strip and form a seal with the tear strip surrounding the opening, the body terminating remote from the plug in a grip portion which has roughened surfacesand which is provided with longitudinally offset transversely extending ribs to facilitate the gripping thereof, the body portion being further provided with a central portion of reduced thickness to permit the initial bending of the pull tab body when gripped so that the necessary gripping of the grip portion may be attained.

Still another object of this invention is to provide a novel plastic pull tab in accordance with the foregoing wherein the pull tab is provided with an aligning pin on the upper surface thereof in alignment with the plug to facilitate the positioning of the pull tab with respect to the tear strip.

Another object of this invention is to provide a novel sheet metal pull tab which is reinforced by means of a central rib wherein the pull tab has a winged channel cross section, the rib being of an increased width adjacent one end of the pull tab and contoured for the reception of a head of a rivet utilized in the attachment of the pull tab to a tear strip. 7

Another object of this invention is to provide a sheet metal pull tab .in accordance with the foregoing, wherein the end thereof remote from the end to which the rivet is attached is reversely curled and bowed transversely of the pull tab to form a grip portion which maybe readily and securely gripped.

A still further object of this invention is to provide a sheet metal pull tab of the type set forth above wherein the side edges of the pull tab are reinforced through the longitudinal curling thereof.

Yet another object of this invention is to provide a container end of the easy opening type wherein a major portion of the end panel thereof is removed by tearing therefrom a tear strip, the tear strip being of an unusually wide width wherein the tear strip has a suflicient cross section to resist the straightening thereof to a generally straight line relationship and the tear strip, when torn from the container end assumes a generally helical configuration whereby the distance between the attached pull tab and the container remains a minimum during the opening of the container thereby greatly facilitating the tearing of the removable portion of the end panel from the container end.

Still another object of this invention is to provide a novel container end construction of the type wherein a major portion of the end panel thereof is torn therefrom in the opening of the container, the removed portion of the end panel including a circumferential tear strip and a central end panel portion, the tear strip being defined by inner and outer score lines with the inner score line terminating considerably short of the terminal portion of the outer score line to provide a rigid connection between the removable central end panel portion and the tear strip whereby the central end panel portion is lifted upwardly with the tear strip during the opening of the container as opposed to pivoting inwardly down into the container whereby the dipping of the removed part of the end panel into the product of the container being opened is eliminated.

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 4 detailed description, the appended claims and the several views illustrated in the accompanying drawings: 7 In the drawings:

.FIGURE 1 is a plan view of a container or can end formed :in accordance with this invention and shows the same attached to a can,the view showing the general outline of both the tear strip and the reinforcement of the can end.

FIGURE 2 is an enlarged fragmentary vertical sectional view taken through the center of the can of FIG- URE'I along the line 22 and shows the specific cross section of the can end. I

FIGURE 3 is an enlarged fragmentary vertical sectional view taken along the line 3-3 of FIGURE 2 and shows the specific details of a plastic pull tab and the connection between the plastic pull tab and the tear strip of the can end.

FIGURES 4, 5 and 6 are fragmentary'enlarged vertical sectional views taken along the

lines

44, 55 and.

66, respectively, of FIGURE 1 and show the cross sections of the score lines or weakening lines defining the.

FIGURE 8 is 'an enlarged fragmentary plan view of the can end of FIGURE 7 and shows the specific details of the pull tab.

FIGURE 9 is an enlarged fragmentary vertical sec-' tional view taken along the line 99 of FIGURE 8 and.

shows the specific relationship of the pull tab to the tear strip.

FIGURE 10 is an enlarged fragmentary vertical sectional View taken along the line 10-40 of FIGURE 9 and shows the specific cross section of the pull tab.

FIGURE 11 is a plan view of the sheet metal blank from which the pull tab of FIGURES 7 through 10 is formed.

FIGURE 12 is a fragmentary top perspective view of the container of FIGURE 2 and shows an intermediate step in the opening of the container, the generally helical configuration of the partially removed tea-r strip being shown.

FIGURE 13 is a fragmentary top perspective view of the container of FIGURE 12 immediately prior to the complete removal of that portion of the end panel which is removed during the opening of the container and shows the manner in which the last-removed portion: of the end panel moves upwardly with the tear strip as opposed to dipping down into the product within the container.

FIGURE 14 is a schematic view showing the outline of the weakening or score lines formed in a container end in accordance with this invention.

FIGURE 15 is an enlarged developed sectional ,view taken along the outer weakening'line and shows the specific variations in depths of the'outer weakening line through the length thereof, an intermediate portion of the weakening line being omitted.

FIGURE 16 is a developed sectional view similar to FIGURE 15 but taken along the inner weakening line.

Referring now to the drawings in detail, it will be seen that there is illustrated in FIGURE 2 a container or can, generally referred to .by the numeral 15.

to by the numeral 16. The can end 16 is secured to a can body 17 of the can 15 in a conventional manner by means of a double seam 18. The can end 16, in accordance with this invention, is of the easy opening type which does not require any opener to effect the opening thereof.

The can 15 is provided with a can' end, generally referred.

In order to facilitate the opening of the can 15, the

can end 16 is provided with a peripheral tear strip 19 V which has a starting end 29. The tear strip 19 has the outer boundary thereof defined by an outer weakening or score line 21 which includes a continuous circular portion. The inner boundary of the tear strip 19 is defined by an inner weakening or score line 22 which, for the most part, is disposed concentric with the weakening line 21. The starting end 20 of the tear strip 19 is, in part,'defined by a starting weakening or score line 23 which connects together inner ends of the weakening lines 21 and 22. The starting end 20 of the tear strip 19 is provided with a pull tab, generally referred to by the numeral 24, to facilitate the rupture of the can end 16 along the weakening lines 21, 2-2 and 23 and thus facilitate the opening of the can 15. The details of the pull tab 24 will be set forth hereinafter.

It has been found that during shipment and other handling procedures cans oftentimes receive impacts of a nature which will rupture the same along one of the weakening lines. It is proposed to reinforce the can end 16 in a manner so as to be of a shock absorbing nature and thus greatly increase the capacity of the can end 16 to receive shock as compared to the other existing types of can ends having tear strips incorporated therein. To this end, it is first to be noted that the tear strip 19 is relatively wide as compared to the size of the can end 16 so that the tear strip in itself has a certain degree of flexibility. The can end is reinforced about a major portion of the weakening line 21 by the provision of an inwardly or downwardly projecting head 25, as is best shown in FIGURE 2. The bead 25 may flex to a certain degree should there be an inwardly-directed force on the can in the vicinity of the seam 18, thus preventing the transfer of rupturing force to the can end 16 along the weakening line 21. In a like manner, the central portion of the can end 16 is reinforced by inwardly or downwardly depressing the same to form an offset centralportion 26 having an upper peripheral wall or shoulder 27 which is disposed adjacent to the inner weakening 'line 22 and to the starting weakening line 23 throughout the extents thereof. 'From the foregoing, it will be seen that by shaping the can end at the time of its forming to provide the internal head 25 and the inwardly offset portion 26 which does not require any additional forming step, the strength of the can end 16 may be greatly increased over the strength of similar can ends. In a like manner, by making the tear strip 19 wide as compared to customary tear strips, n certain degree of resistance to rupture may be obtained through the flexing of the tear strip 19 without any sacrifice in the opening advantages of the can end as compared to other can ends since the tearing of the tear strip is endwise and the width of the tear strip is immaterial as far as opening forces are concerned. An incidental but advantageous result of the inward offsetting of the central portion 26 of the can end 16 is to provide clearance for a grip portion of the pull tab 24, as is shown in FIGURE 3, to facilitate the gripping thereof.

Reference is now made to FIGURES 4 through 6 and 14 through 16 wherein the specific details of the several weakening lines are shown. The weakening lines 21, 22 and 23, which are in the form of scores, are of different depths so that the various portions of the can end 16 have various resistances to tearing, thereby facilitating the proper opening of the can end. It is to be-noted that the weakening or score line 23 is the deepest whereby the can end 16 is the weakest along the weakening line 23 and thus the initial tearing of the tear strip 19 from the can end 16 may be facilitated.

It is to be noted that the weakening line 21 is of a greater depth than the weakening line 22. At this time it is pointed out that it is desirable that the tearing of the tear strip 19 from the remainder of the can end 16 be uniform. Therefore, the tearing along the score lines 21 and 22 should remain uniform and in radial alignment. It is first to be noted that the score line 21, being the outer of the two score lines, is of a greater length, and therefore, the tear along the score line 21 is much longer than the tear along the score line 22'. Therefore, in order that the total tearing force along the two weakening

lines

21 and 22 will be substantially the same, the score line 21 has been made deeper than the score line 22. Furthermore, there is a general tendency to hold the pull tab '24 in a manner wherein a maximum tearing force is applied on the can end along the weakening line 22. It has been found that the specific relationship of score line depths shown in FIGURES 4 through 6 and 14 through 16 provides for a tear strip arrangement which will be easily and uniformly torn from the can end.

Reference is now particularly made to FIGURES l4 and 15 with respect to the outer weakening line 21 and the associated part of the weakening line 23. Starting at point A in FIGURE 14, which is at the center of the weakening line 23, and continuing entirely around the outer weakening line 21, 'it will be readily apparent from FIGURE 15 that the outer score line greatly varies in depth from one end to the other. The portion of FIG- URE 14 between A and B is the. starting weakening line 23. It will then be seen that the depth of the score line gradually decreases for a short distance until the depth becomes constant and the final score line depth of the score line 21 is reached. This transition portion of the score line 21 is referred to by the numeral 50. The score line 21 continues around a major portion of the can end at a constant depth until it reaches point C near the terminal end of the score-line 21, as is shown in FIGURE 14. At point C, with reference to FIGURE 15, the depth of the score line 21 abruptly decreases, as at 51, until it reaches a minimum at 52. The score line 21 then has a transition portion 53 which provides for a rapid increase in score line depth. The transition portion 53 is followed by a final score line portion 54 which may slightly increase in depth to the terminal end of the score line 21 at D. The specific configuration of the score line 21 will be described in detail hereinafter.

Referring now to FIGURES 14 and 16, it will be seen that starting at A and moving along the weakening line towards the weakening line 22, the score line is of a constant depth until the point E is reached, at which point the score line 22 starts. The score line portion between A and E is the score or weakening line 23. At E the depth of the score line begins to decrease and there is a transition portion 55. The 'depth of the score line reduces until it becomes of a constant depth which is the depth of the score line shown in FIGURE 5. The depth of the score line 22 remains constant until the terminal end thereof is reached at F at which point the score line diminishes to nothing. Y

Referring now to FIGURES 1 and 3, it will be seen that the pull tab 24 is formed of a flexible plastic material and includes an elongated body 28 which is provided at one end thereof with a downwardly projecting part 29 carrying a tubular plug 30. The plug 39 is provided with a rounded lower end 31 which opens internally into a bore 32 and continues externally into a tapered portion 33. The plug 30 is of a reduced cross section, as at 34, to define a shoulder 35.

The body 28 of the pull tab 24 is downwardly thickened, as at 36, so as to leave an intermediate portion 37 which is the thinnest and thus which is the weakest part of the pull tab body 28. The thickened part 36 of the pull tab body is disposed upwardly at a slight angle to the plane of the remainder of the body 28.

The thickened part 36 of the pull tab body terminates at its outer end in a downwardly sloping offset portion 38 which, in itself, may be considered part of a grip portion 39 of the pull tab 24. The grip portion 39 includes a sloping portion 40 which is integrally connected to the connecting portion 38 and Which'ex'tends generally parallel to the thickened portion 36. The grip portion 39 includes a terminal transversely extending rib 41 on the upper surface thereof. A second transverse rib 42 projects downwardly from the underside of the upwardly sloping portion 40 in longitudinally offset relation with respect to the rib 41.

It is to be noted from FIGURE 1 that the grip portion 39 of the pull tab 24 has concavely curved side edges 43.

tearing out of the removable portion of the can end is accomplished. a

Reference is now made to FIGURE 13 wherein it is shown that due to the rigidity of the depressed central portion 26, and the fact that the score line 22 terminates far short of the terminal end of the tear strip 19, it will be seen that the central portion 26 remains firmly attached to the tear strip 19 and remains in the plane of the asso Further, the upper and lower surfaces of the grip portion 19 so that the plug 30 effectively seals the opening 45..

At this time it is pointed out that the pull tab body 2 28 is provided with an upwardly projecting centering pin 47 which is co-axial with the plug 30and may be suitably engaged by a pull tab applying tool (not shown) wherein centering of the plug 30 with the tear strip opening 45 may be assured during the application of the pull tab 24 to the tear strip 19.

It is also to be noted that the relative construction of the pull tab 24 and the can end 16 is such that the grip portion 39 of the pull tab is partially recessed within the recessed central portion 26 of the can end 16, and at the same time gripping of the grip portion 39 may be I readily facilitated.

Reference is now particularly made to FIGURES 12 through 16 wherein the various stages in the opening of the can end 16 are shown. It is to be understood that in the opening of the can end 16, an upward force is directed onto the pull tab 24 which, through its connection, exerts an'upward force on the starting end 20 of the tear strip 19. Sufiicient force may be readily placed upon the starting end 20 to rupture the can end along the weakening line 23. A continued upward pull on the pull tab 24 results in the tearing of the tear strip 19 from the remainder of the can end 16 along the weakening

lines

21 or 22. Due to the fact that the tear strip 19 is very wide as compared to the normal narrow tear strip, and because of the differential in lengths of the weakening lines 21 and 22, it will be seen that as the tear strip 19 is removed from the can end 16, it does not assume the straight line relation normally assumed by narrow tear strips, but assumes a generallyhelical configuration, as is clearly shown in FIGURE 12. Due to the generally helical configuration of the removed portion of the tear strip 19, the distance between the pull tab 24 and the can end 16 remains at a minimum and this distance is one wherein the" continued removal of the tear strip 19 may be conveniently accomplished.

The tearing of the tear strip 19 from the can end 16 continues until point C on the weakening line 21 is reached. Atthis point tearing along the weakening line 22 hasbeen completed and the tearing of that portion of the can end which is to be removed is restricted to being along the weakening line 21. It is to be noted from FIG-. URE that the score line 21 becomes shallow starting at C and thus the resistance of the metal to tearing rapidly increases with the result that there is a momentary slowing down of the tearing operation. This also serves as a warning to the person opening the container 15 that the opening process is nearingan end. The general tendency of this increased resistance to tearing is for the person to momentarily stop tearing of the tear strip, after which the tearing operation is renewed and the final ciated portion thereof, Thus, during the final stages of the opening of the container 15, the central portion 26-: is lifted with the tear strip 19 in the manner shown in FIGURE 13, and as opposed to pivoting into the product within the container 15, the removed portion of the container end 16 is lifted directly out of the plane of the end panel thereof. This eliminates the accumulation of the contents of the container 15 on the removed portion of the can end 16 and thereby splashing, which has occurred in the past with other types of easy opening container ends, is eliminated.

Referring now to FIGURES 7 through 11, it will be seen that there is illustrated a slightly modified form of a can end construction. The can end is part of a can, generally referred to by the numeral and in itself is referred to by the numeral 116. The can end 116 is identical with the can end 16 with the exception of a' minor variation in the construction of the tear strip thereof, the

tear strip being referred to by the numeral 119. Since all other portions of the can 115 are identical with like portions of the can 15 with the exception of a pull tab,

which is referred to by the numeral 120, like numerals will:

be given to like previously described parts.

In lieu of the flanged opening 45 formed in the tear strip 19, the tear strip 119 is provided with an integral upstanding tubular rivet 121'which is crimped, as at 122,

to define an enlarged head 123. The rivet 121 passes through an opening 124 in the pull tab and the head 123 serves to retain the pull tab 120 on the rivet 121.

It is to be noted that the pull tab 120 is formed of sheet metal and is formed from a blank generally referred to by the numeral 125. The blank 125 includes a body portion 126 which is generally trapezoidal in outline and includes two diverging side edges 127, a narrow end 128.

and a wide end 129.

Wings

130 and 131 are connected to the pull tab body 126 along the side edges 127 of the end 128, respectively.

The body 126, for the major portion of the length thereof, is of a winged channel cross section, as is best shown in FIGURE 10. The body 126 is provided with a longitudinally extending depressed rib 132 which is widened adjacent the end 129, as at 133, to provide clearance for the head 123 of the rivet 121. The rib 132 has a base 134, as is shown in FIGURE 10. The base 134 becomes very enlarged and extends the full width of the body 126 at the end 129 thereof. The base 134 has the opening 124 formed therein.

It is to be notedthat the rib 132 reinforces. the body 126 against bending transversely of the axis of the pull tab 120. The pull tab 120 is further reinforced by means of the curling of the wings 130 to define longitudinally extending curled reinforcing edges 135.

The end of the pull tab 120 remote from the rivet 121 is transversely and upwardly bowed, as at 136. Partof this how is formed in the wing 131 and part is formed in the body 126. Immediately adjacent the body 136 the wing 131 is upwardly r'eversely curled to define a curled transverse enlargement 137 which, together with the body portion 136, defines a grip portion of the pull tab 120.

It will be readily apparent that the pull tab 120 may be formed of relatively thin sheet metal and due to the specific configuration thereof, it will have sufficient strength to resist-bending when an upward force is directed thereupon during the initial tearing or breaking of the tear strip 119 along the starting line thereof. At thesame time, the connection between the rivet 121 and the pull tab 120 will be sufficient to resist any accidental rupture of the pull tab 120 from the tear strip 119. At this time it is pointed out that the grip portion of the pull tab 120 overlies the inwardly offset central portion 24 of the can end and thus facilitates the gripping thereof.

It is to be understood that the can end 116 has all of the structural advantages of the can end 16 and that. the difference between the can end 116 as compared to the can end 16 is the difference in pull tab construction and the manner of attaching the two pull tabs to their respective tear strips.

It will be understood that when the can end 116 is opened utilizing the pull tab 120, the opening operation will be that described with respect to the can end 16 and shown in FIGURES 12 and 13.

Although only preferred embodiments of the invention have been specifically illustrated and described herein, it is to be understood that minor modifications may be made in the can end construction in accordance with this invention within the spirit and scope of this invention, as-

said tear strip, said container end having an oflset central portion having a border of which a major portion thereof conforms in outline to said inner weakening line, said offset central portion sitflening said can end and thereby resisting parting of said weakening lines, and said inner weakening line terminating into said offset portion, with said otfset central portion being carried by a terminal portion of said tear strip after the complete separation of said inner weakening line and maintaining its normal relationship to said tear strip during the final stages of tear strip removal whereby tilting of said offset central portion down into the interior of an associated container is prevented, said outer weakening line being of a maximum strength adjacent to but spaced from a terminal end thereof whereby during an opening operation there is a momentary slowing down of the opening operation prior to the final removal of said tear strip and springing of said central portion towards the starting end of said tear strip is restricted, and said outer weakening line being of a reduced strength between said maximum strength.

portion and said terminal end to facilitate the final re moval of said tear strip.

2. In a container end of the type wherein a major portion of an end panel thereof is removed, a peripheral weakening line having a terminal end, said weakening line being of a maximum strength adjacent to but spaced from said terminal end whereby during an opening operation there is a momentary slowing down of the opening operation prior to the final removal of said end panel removable portion and springing of said removable portion away from the plane of said end panel is restricted, said weakening line being of a reduced strength between said maximum strength portion and said terminal end to portion.

No references cited.

THERON E. CONDON, Primary Examiner.

Claims

1. A CONTAINER END, A TEAR STRIP DEFINED IN SAID CONTAINER END BY AN OUTER PERIPHERAL WEAKENING LINE AND AN INNER WEAKENING LINE CONNECTED TOGETHER BY A CONNECTING STARTING WEAKENING LINE IN PART DEFINING A STARTING END OF SAID TEAR STRIP, SAID CONTAINER END HAVING AN OFFSET CENTRAL PORTION HAVING A BORDER OF WHICH A MAJOR PORTION THEREOF CONFORMS IN OUTLINE TO SAID INNER WEAKENING LINE, SAID OFFSET CENTRAL PORTION SITFFENING SAID CAN END AND THEREBY RESISTING PARTING OF SAID WEAKENING LINES, AND SAID INNER WEAKENING LINE TERMINATING INTO SAID OFFSET PORTION, WITH SAID OFFSET CENTRAL PORTION BEING CARRIED BY A TERMINAL PORTION OF SAID TEAR STRIP AFTER THE COMPLETE SEPARATION OF SAID INNER WEAKENING LINE AND MAINTAINING ITS NORMAL RELATIONSHIP TO SAID TEAR STRIP DURING THE FINAL STAGES OF TEAR STRIP REMOVAL WHEREBY TILTING OF SAID OFFSET CENTRAL PORTION DOWN INTO THE INTERIOR OF AN ASSOCIATED CONTAINER IS PREVENTED, SAID OUTER WEAKENING LINE BEING OF A MAXIMUM STRENGTH ADJACENT TO BUT SPACED FROM A TERMINAL END THEREOF WHEREBY DURING AN OPENING OPERATION THERE IS A MOMENTARY SLOWING DOWN OF THE OPENING OPERATION PRIOR TO THE FINAL REMOVAL OF SAID TEAR STRIP AND SPRINGING OF SAID CENTRAL PORTION TOWARDS THE STARTING END OF SAID TEAR STRIP IS RESTRICTED, AND SAID OUTER WEAKENING LINE BEING OF A REDUCED STRENGTH BETWEEN SAID MAXIMUM STRENGTH PORTION AND SAID TERMINAL END TO FACILITATE THE FINAL REMOVAL OF SAID TEAR STRIP.