US3618816A

US3618816A - Tab for easy-opening container wall

Info

Publication number: US3618816A
Application number: US30649A
Authority: US
Inventors: Omar L Brown
Original assignee: Dayton Reliable Tool and Manufacturing Co
Current assignee: Dayton Reliable Tool and Manufacturing Co
Priority date: 1970-04-22
Filing date: 1970-04-22
Publication date: 1971-11-09
Anticipated expiration: 1988-11-09

Abstract

A tab including a lever portion and a handle portion integrally connected to one end of the lever portion by a pliable portion. The other end of the lever portion is suitably connected to a tear portion of a container wall. In use, the handle portion is raised as permitted by the pliable portion until the handle portion is at an appropriate angle to exert a lifting force on the lever portion. Then an outward pulling force is applied to the handle portion to initiate severance of the tear portion with the lever action of the lever portion.

Description

United States Patent Inventor Omar L. Brown Dayton, Ohio Appl. No. 30,649

Filed Apr. 22, 1970 Patented Nov. 9, I971 Assignee Dayton Reliable Tool & Mfg. Company Dayton, Ohio TAB FOR EASY-OPENING CONTAINER WALL 17 Claims, 18 Drawing Figs.

us. Cl 220/54, 220/48 m'. CI. 365d 17/24 Field oiSearch 220/27, 54,

[56] References Cited UNITED STATES PATENTS 3,22 l .924 l2/l965 Harrey et al. 220/48 X 3,462,036 8/ l 969 Siemonsen et al 220/54 X Primary Examiner-George T. Hall Allorney-Smyth, Roston & Pavitt ABSTRACT: A tab including a lever portion and a handle portion integrally connected to one end of the lever portion by a pliable portion. The other end of the lever portion is suitably connected to a tear portion of a container wall. in use, the handle portion is raised as pennitted by the pliable portion until the handle portion is at an appropriate angle to exert a lifting force on the lever portion. Then an outward pulling force is applied to the handle portion to initiate severance of the tear portion with the lever action of the lever portion.

PATENTEnunv 9 197a SHEET 2 OF 6 Omar Z. draw/ M "2.3g

A7701 n ny TAB FOR EASY-OPENING CONTAINER WALL As is well known, an easy-opening container wall typically includes a container wall having a line of weakness therein defining a tear portion and a tab connected to the tear portion for removing the tear portion. To remove the tear portion the tab is raised to initiate severance of the tear portion and then pulled outwardly to completely sever the tear portion from the container wall.

Tabs for use on easy-opening containers are either front opening or rear opening. With a front-opening tab, the forward or nose end of the tab forces a segment of the tear portion inwardly of the container wall to initiate severance of the tear portion. In a rear-opening tab, an intermediate portion of the tab lifts up on the leading end of the tear portion to initiate its severance from the container wall.

A problem with both types of tabs is to make the tear portion more easily removed. Specifically, it is desirable to make the initiation of severance of the tear portion easier as following the initial severance of the tear portion, the tear portion can usually be easily torn from the container wall.

Tab construction materially eflects the ease of rupture of the line of weakness. First, it is desirable 'to use a tab having substantial mechanical advantage. In addition, and perhaps more important, is that the tab should be easy to lift off the container wall a sufi'rcient distance to get a finger beneath or through the opening in the tab. With the tab initially raised to permit the user to firmly grasp same, substantial force can be applied to the tear portion.

Prior art tabs provide sufficient mechanical advantage but in many cases prior art tabs are not sufiiciently easy to lift off of the container wall. This is because the tab immediately upon lifting becomes effective to apply stress to the score line. Thus, the lifting force applied to the tab is substantially resisted from the outset.

In an effort to provide ease of lifting coupled with adequate mechanical advantage, one prior art tab is constructed from two separate pieces of wire. One difficulty with this construction is that wire is difficult and expensive to form, and the twopiece construction necessitates a separate assembly step. The assembly step is particularly undesirable because of the extremely high volume of tabs which the easy open end industry requires. In addition, the can end must be recessed in a particular manner to accommodate the joint between the twowire segments.

In another similar prior art construction, the tab includes a sheet metal portion and a plastic pull ring with the metal and plastic portions being clamped together. This tab is particularly difficult to make in that it requires the usual sheet metal forming operations on the sheet metal segment of the tab coupled with molding or forming of the plastic pull ring segment of the tab. In addition, a separate assembly step coupled with the usual problems of part feeding and indexing is required. As explained above, this is particularly undesirable where high volume production is necessary.

The present invention provides a one-piece tab which can be easily manually raised any desired amount with ease. The tab does substantially no work during the initial lifting thereof and accordingly this operation requires-minimal force. With the present invention, one-piece tab construction is made possible whether the tab is constructed of metal or plastic.

A tab constructed in accordance with this invention may include a lever portion and a handle portion or gripping segment joined to the lever portion with a pliable connecting portion. The lever portion is connectable to the tear portion at one end and to the handle portion at the other end. With this construction, the outer or handle end of the handle portion can be easily moved away from the container wall without substantial resistance. Thus, the tab of this invention differs from many prior art tabs in that it does not rupture the line of weakness or any other portion of the container wall during the initial lifting phase. Rather, rupture of the line of weakness is accomplished by exerting an outward pulling force on the previously raised tab. Such outward pulling force causes a lifting force to be applied to the outer end of the lever portion with consequent initiation of severance of the tear portion by the lever portion.

Preferably the handle portion has a finger-receiving opening therein to facilitate grasping thereof. The handle portion preferably extends from its juncture with the lever portion generally in the direction of the location at which the lever portion is attached to the tear portion. Stated differently, the outer or handle end of the handle portion preferably lies on the same side of the connecting portion as the lever portion. One advantage of this construction is that the lever portion may be constructed of material which would otherwise be scrapped as a result of the formation of the finger-receiving opening in the handle portion. Another advantage of this construction is that the degree of bending necessary to raise the handle portion to an optimum angle for exerting the outward pulling force is minimized to the extent that the material making up the connecting portion is fatigued a minimum amount.

Preferably the handle portion is sufi'rciently rigid to also be a lever. The handle portion preferably has a bearing region which is adapted to engage the container wall and which is on the opposite end of the handle portion from the handle end. The handle portion is pivotally connected to the lever portion by the pliable portion intermediate the ends of the handle portion and closely adjacent the bearing region. This pivotal connection may be considered as an integral hinge. The connecting portion joins the handle portion to a lifting region of the lever portion. The fulcrum of the lever portion is at the end thereof opposite from the connecting portion.

With this construction, the handle end of the tab can be moved away from the container wall with consequent pivoting of the handle portion about the pliable connecting portion. If the bearing region is sufficiently close to the container wall it will bear against the container wall and slide a short distance therealong. As the bearing region slides along the container wall, the lifting region of the lever portion is lifted slightly. Because of the mechanical advantages of the handle portion and lever portion, this initial lifting of the lever portion is insufficient to rupture the line of weakness regardless of the number of degrees through which the handle portion is pivoted. This makes initial lifting of the handle end very easy. The tab of this invention can be used as either a frontor rearopening tab.

The invention, both as to its organization and method of operation together with further features and advantages thereof, may best be understood by reference to the following description taken in connection with the accompanying illustrative drawings.

FIG. 1 is a plan view of an easy-opening container wall constructed in accordance with the teachings of this invention.

FIG. 2 is an enlarged fragmentary plan view of a portion of the easy-opening container wall.

FIG. 3 is an enlarged sectional view taken along line 3-3 of FIG. 1.

FIGS. 4-6 are fragmentary sectional views showing the easy-opening container wall installed on a can body and illustrating the sequence of operation of the tab.

FIG. 7 is a plan view of another form of easy-opening container wall embodying the principles of this invention.

FIG. 8 is an enlarged fragmentary plan view of a portion of the container wall of FIG. 7.

FIG. 9 is a sectional view taken along line 9-9 of FIG. 8.

FIGS. 10 and 11 are fragmentary sectional views similar to FIG. 9 illustrating the sequence of operation of the tab.

FIG. 12 is a plan view of a third form of easy-opening container wall constructed in accordance with the teachings of this invention.

FIG. 13 is an enlarged fragmentary plan view of a portion of the easy-opening container of FIG. 12.

FIG. 14 is a fragmentary sectional view taken along line 14-14 ofFIG. 13.

FIG. 15 is a plan view of another of a tab of plastic material constructed in accordance with the teachings of this invention.

FIG. 16 is a sectional view taken along line 16-16 of FIG. 15.

FIGS. 17 and 18 are sectional views taken along lines l7- l7 and 18-18, respectively, of FIG. 15.

Referring to the drawings and in particular to FIG. 1 thereof, reference numeral 11 designates an easy-opening container wall constructed in accordance with the teachings of this invention. The easy-opening container wall 1 1 includes a can end 13 of sheet aluminum or other suitable sheet material having a peripheral attachment bead 15 for attaching the container wall 13 to a can body 17 (FIGS. 4-6). A line of weakness in the form of a scoreline 19 in the container wall 13 defines an elongated tear portion 21 which is removable from the container wall. A tab 23 is attached to the leading end of the tear portion 21 by suitable means such as a hollow rivet 25 formed integrally with the leading end of the tear portion.

The tab 23 in the embodiment illustrated is integrally constructed from a single piece of sheet aluminum and includes a lever portion 27 (FIG. 2) and a handle portion 29 integrally joined by a pliable connecting portion 31. The lever portion 27 has a lifting end or region 33 and a fulcrum end 35. Intermediate the ends 33 and 35, the rivet 25 projects through an aperture 37 in the lever portion 27 to attach the tab 23 to the leading end of the tear portion 21. As best shown in FIG. 3, the tab lies flat against the container wall 13.

The lever portion 27 is stiffened longitudinally by integral reinforcing beads 39 and 41 which are formed by curling marginal longitudinal portions of the lever portion. The lever por tion 27 is further stiffened by a central rib 43 extending longitudinally of the tab. The fulcrum end is defined by a bead 45 of sheet material which is rolled up against the ends of the beads 39 and 41. As shown in FIG. 2, the distance between the connecting portion 31 and the rivet 25 is many times greater than the distance between the rivet 25 and the fulcrum end 35. This provides the lever portion 27 with substantial mechanical advantage in initiating severance of the score line 19.

The handle portion 29 lies in substantially the same plane as the lever portion 27 and completely surrounds the latter. The handle portion 29 has a handle end or lifting end 47, a bearing region or end 49 and a large finger receiving opening 51. A marginal portion of the handle portion 29 is turned inwardly to define an outer reinforcing bead 53 which extends for a substantial distance around the handle portion 29. The sheet material surrounding the opening 51 is turned outwardly to define an inner reinforcing bead 55 which extends for a substantial distance around the opening 51. A planar region 57 of sheet material extends between the ends of the

beads

53 and 55 and is elevated above the container wall 13 as shown in FIG. 3. The

beads

53 and 55 stiffen the handle portion 29.

In the embodiment illustrated, the handle portion 29 also serves as a lever which is hinged to the lever portion by the connecting portion 31. As shown in FIGS. 2-6, the hinge lies closely adjacent the bearing end 49 and is quite remote from the lifting end 47 so that the handle portion 29 has substantial mechanical advantage.

The connecting portion 31 integrally joins the region 57 to the lifting end 33. As shown in FIG. 3, the connecting portion 31 slopes downwardly from the region 57 to the lifting end 33. The connecting portion is pliable so as to permit relative pivotal movement between the handle portion 29 and the lever portion 27. In the embodiment illustrated, the lever portion 27 is constructed from the sheet material which would otherwise be scrapped as a result of the formation of the opening 51. The lever portion 27 extends diametrically for considerably more than one half of the diameter of the opening 51.

The operation of the device is shown in FIGS. 4-6. By moving the lifting end 47 away from the container wall 13, the handle portion 29 pivots relative to the lever portion 27 as permitted by the pliable connecting portion 31. Such pivotal movement of the handle portion 29 continues with the only resistance being the resistance afiorded by the pliable sheet material of the connecting portion 31 until the bearing region 49 of the tab firmly engages the container wall 13 as shown in FIG. 4. The angle of the handle portion 29 at which the bearing region 49 engages the container wall 13 will vary depending upon the dimensions and arrangement of the tab. If desired the bearing region 49 can be eliminated so that pivotal movement of the handle portion would not result in any lifting of the lever portion 27.

In pivoting the handle portion 29 to the position shown in FIG. 4, the bearing region forcibly engages the can end 13 and slides therealong with the result that the connecting wall 31 applies an upward lifting force to the lifting end 33 of the lever portion 27. The degree of lifting accomplished is sufiiciently small so that the line of weakness 19 does not rupture. There will, however, be some upward force applied to the lifting end 33 with the result that the score line 19 may be lightly stressed. Because of the large mechanical advantage of the handle portion 29 and of the lever portion 27, the handle portion 29 can be moved to the position shown in FIG. 4 with considerable ease. Next, the user exerts an outward pulling force on the handle portion 29 to initate severance of the tear portion 21 as shown in FIGS. 5 and 6. Of course, continued pulling of the handle portion 27 results in complete removal of the tear portion 21.

During the removal of the tab, the bead 45 causes the material of the tear portion 21 to gently bend around the bead 45 rather than forming a sharp bend line. This materially reduces the likelihood of fracturing the sheet material of the tear portion during the removal operation. This gentle bend in the tear portion 21 may straighten out when the tab 23 is pulled outwardly as shown in FIG. 6.

FIGS. 7-11 illustrate a second form of easy-opening container wall 11a in which parts corresponding to parts illustrated in FIGS. 1-6 are designated by corresponding reference characters followed by the letter a. The easy-opening container wall 11 includes an aluminum closure 13a of the type particularly adapted for attachment to the mouth of a bottle or jar and which can be completely removed therefrom. A closure of this general type is disclosed, for example, in US. Pat. No. 3,441,163 issued to Robert L. LaBarge.

The container wall has a scoreline 190, one end of which extends all the way to the periphery of the closure 13a and the other end of which terminates in a hook-shaped portion on the end wall of the container wall 13a. The scoreline 19a defines a tear portion 21a which is only partially removable from the container wall. To facilitate splitting apart of the container wall 130 following partial removal of the tear portion 21, a plurality of generally radially extending scorelines 22 are provided in the end wall of the closure 13a.

A tab 23a is affixed to the leading end of the tear portion 210 by a rivet 25a. Except in the respects specifically shown or described, the tab 23a is identical to the tab 23.

The tab 23a includes a lever portion 27a, a handle portion 290 and a connecting portion 310 for interconnecting the lever portion and the handle portion. The lever portion 270 is identical to the lever portion 27 except that the rib 43 has been eliminated and a single bead 59 extends continuously along the longitudinal edges of the lever portion and around the nose end of the lever portion where it is lanced and bent downwardly to define a rupturing point as shown in FIGS. 7-1 1.

The handle portion 290 is identical to the handle portion 29 except that the former is circular in plan and has an outer bead 530 which extends nearly completely around the outer periphery of the handle portion. In addition, the handle portion 29a has an inner bead 55a which extends all the way to the connecting portion 31a. Also the bead 59 is lanced at two places at the end thereof adjacent the rivet 25a and flattened (FIGS. 9-11) to form a piercing element 60. The piercing element terminates in a relatively sharp point 62 which assists in rupturing of score 190. Because the piercing element 60 engages the container wall at the end of the tab remote from the rivet 250, the undersurface of the bead 53a becomes a bearing region.

As shown in FIG. 10, movement of the lifting end 47a of the handle portion 29a away from the container wall 13 causes the handle portion to pivot relative to the lever portion as permitted by the pliable connecting portion 31a. This causes the bearing region 490 to bear against the container wall 13a and to possibly slide a short distance toward the rivet 25a. In any event, the pivotal movement of the handle portion 29a results in the application of a minor lifting force to the lever portion 27a which force is insufficient to rupture the line of weakness 19a. The lifting force applied to the lever portion 27a stresses the score line 19a slightly. The lifting end 47a can be raised easily to the desired elevation at which time an outward lifting force is applied as shown in FIG. 11 to initiate severance of the tear portion 21. As shown in FIG. 11, the bead 59 depresses a region of the tear portion 21 downwardly or into the container to initiate rupture of the score line 19a in front-opening fashion.

FIGS. 12-14 illustrate an easy-opening container wall 11b in which parts corresponding tovparts shown in FIGS. 1-6 are designated by corresponding reference characters followed by the letter b. Except as specifically shown or described, the easy-opening characters 11 and 1 lb are identical.

The tab 23b has a lever portion 27b with longitudinal beads 39b and 41b. The beads 39b and 41b terminate in fulcrum ends 61 and 63 which overlie regions of the can end 13b outside the area of the tear portion 21b. Although the position of the fulcrum ends 61 and 63 can be varied, in the embodiment illustrated, they lie generally along the line which would approximately bisect the rivet 25b.

The lever portion 27b differs from the lever portion 27 in that it is attached to the tear portion 21b with a mounting ear 65 which is joined by a pliable region 67 to the lever portion 27b. Thus, the lever portion 27b can pivot relative to the mounting ear 65 around a line x-x shown in FIG. 13. The lever action obtainable with the lever portion 27b is the same as that shown and described in Brown US. Pat. No. 3,303,959.

The handle portion 29b is identical to the handle portion 29 except that the former is circular in plan and has a circular opening 51b therein. In addition, the handle portion 29 has a bead 53b which extends continuously and completely around the outer periphery of the handle portion and an inner bead 55b which extends substantially completely around the opening 51b and terminates at the connecting portion 31b.

The operation of the tab 23b is identical to the tab 23 except that the bead 53b could be expected to define a bearing region 49b which would engage the can end 13b. When the lifting end 33b is elevated in response to pivotal movement of the handle portion 29b, the lever portion 27b pivots slightly about the line x-x relative to the mounting ear 65. As explained in the above-mentioned Brown patent, the initial lifting of the lifting end 33b is insufficient to cause the fulcrum ends 61 and 63 to be rigidly supported by the container wall 13b and accordingly such initial lifting is resisted only by the force required to bend the metal of the mounting ear 65 along the line xx. When the handle portion 29b is pulled outwardly, the lever portion 27b will pivot about the line x-x with the beads 27b and 39b remaining rigid until the fulcrum ends 61 and 63 are rigidly supported by the container wall 13b at which time the lever portion 27b becomes effective as a second class lever to apply an upward lifting force to the leading end of the tear portion 21b. By continuing the upward lifting, the sheet material along the scoreline 19b is ultimately ruptured with the lever portion 27b functioning as described more fully in the above-mentioned Brown patent.

FIGS. -17 illustrate a tab 71 which is functionally similar to the

tabs

23, 23a and 23b. The tab 71 differs from the abovedescribed tabs in that it is integrally molded of plastic material.

The tab 71 is identical to the tab 23 in all respects not specifically shown or described herein. The tab 71 includes a lever portion 73 and a handle portion 75 integrally connected by a bendable connecting portion 77. The lever portion 73 has an integral peripheral bead 79 extending along three sides thereof and an integral central bead 81 both of which serve to stiffen the lever portion longitudinally. As shown in FIGS. 17 and 18, the

beads

79 and 81 are enlargements of the lever portion cross section. The bead 79 has a curved surface 83 extending along the transversely extending portions thereof as shown in FIG. 16 which serves the same purposes as the curved bead 45 (FIG. 2). The lever portion 73 has an aperture 85 for receiving a rivet or other suitable means for attaching the same to the tear portion of a container wall. The lever portion 73 has a lifting end 87 adjacent the connecting portion 77.

The handle portion 75 surrounds the lever portion 73 and is generally coplanar therewith. The handle portion 75 has a finger-receiving opening 89, a lifting end 91 and a bearing region 93. The handle portion 75 is preferably substantially rigid longitudinally and the connecting portion 77 should provide for some pivotal movement of the handle portion relative to the lever portion 73 generally along a line 95. The tab 71 can be used as described hereinabove.

To strengthen the tab 71 around the aperture 85 a metal washer 97 is embedded in the lever portion 73. The washer 97 surrounds the aperture 85 and is preferably nonplanar in cross section to provide greater resistance to bending. The tab may be molded around the washer 97. The additional strength imparted by the washer is important because the region of the tab immediately surrounding the rivet receiving aperture 85 is subjected to high stress during operation of the tab. The washer 97 may be omitted; however, such omission would increase the likelihood of structural failure of the tab around the aperture 85.

Although exemplary embodiments of the invention have been shown and described, many changes, modifications and substitutions may be made by one having ordinary skill in the art without necessarily departing from the spirit and scope of this invention.

I claim:

1. A one-piece tab of the type attachable to a tear portion of an easy-opening container wall to initiate severance of the tear portion from the container wall comprising:

a leverportion of sheet material having integral means for stiffening the lever portion, said lever portion having an attachment location at which the lever portion can be attached to the tear portion, said lever portion extending away from said attachment location to define a lifting region;

a gripping element of sheet material, said gripping element having a first end and a connecting location adjacent the other end thereof, at least portions of said gripping element and said lever portion being in substantially the same plane;

a pliable connecting portion of sheet material for integrally interconnecting the lifting region of the lever portion to the connecting location of the gripping element, said con necting portion being bendable to permit substantially unrestricted pivotal movement of said gripping element relative to said lever portion in a direction tending to move the first end away from the container wall, said first end of said gripping element lying on the same side of said connecting portion as said attachment location; and

the gripping element being manually pullable to move the lifting region of the lever portion away from the container wall to initiate severance of the line of weakness of lever action of said lever portion.

2. A tab as defined in claim 1 wherein a portion of the sheet material of said gripping element is turned to form a bead, said bead stiffening the gripping element and defining a relatively smooth surface for engagement by the finger of the user.

3. A tab as defined in claim 1 wherein said tab is integrally constructed of plastic material.

4. A tab as defined in claim 1 wherein the lever portion has an end adjacent the attachment portion and the sheet material of the lever portion at said end thereof is turned out of the plane of the lever portion.

5. A one-piece tab of the type attachable to a tear portion of an easy-opening container wall to initiate severance of the tear portion from the container wall comprising:

an elongated lever portion of sheet material having integral means for stiffening the lever portion, said lever portion having an attachment location at which the lever portion can be attached to the tear portion, said lever portion extending away from said attachment location to define a lifting region;

a gripping element of sheet material, said gripping element having a first end and a connecting location adjacent the other end thereof, said gripping element having a finger receiving opening, at least portions of said gripping element and said lever portion being in substantially the same plane;

a pliable connecting portion of sheet material for integrally interconnecting the lifting region of the lever portion to the connecting location of the gripping element, said connecting portion being bendable to permit substantially unrestricted pivotal movement of said gripping element relative to said lever portion in a direction tending to move the first end away from the container wall; and

the gripping element being manually pullable to move the lifting region of the lever portion away from the container wall to initiate severance of the line of weakness by lever action with the sole lever action being derived from said lever portion.

6. An easy-opening container wall comprising:

a container wall of sheet material having a line of weakness therein defining a tear portion at least partially removable therefrom;

a tab constructed of sheet material and having a lever portion and a handle portion integrally joined by a connecting portion of sheet material, said handle portion at least partially being in substantially the same plane as said lever portion, said lever portion having an attachment location and said handle portion having an outer end;

means for attaching said lever portion at said attachment location to said tear portion adjacent said line of weakness so that said tab overlies the container wall;

said lever portion extending away from said attachment location to define a lifting region of said lever portion, said connecting portion integrally joining said handle portion to said lever portion at said lifting region, said outer end of said handle portion lying on the same side of said connecting portion as said attachment location; and

said connecting portion being bendable to permit movement of said outer end of said handle portion a substantial distance away from said container wall with consequent pivotal movement of said handle portion relative to said lever portion to thereby expose said handle portion for easy manual gripping thereof, such pivotal movement of said handle portion being incapable of causing said lever portion to rupture said line of weakness whereby pulling outwardly on said handle portion following the pivotal movement thereof lifts said lifting region of said lever portion sufficiently to cause said lever portion to rupture said line of weakness.

7. A container wall as defined in claim 6 wherein said line of weakness defines a tear portion with a relatively narrow leading end, said attachment means being at said leading end of said tear portion, said lever portion having an end portion on the opposite side of said attachment location from said lifting region, the sheet material of said end portion of said lever portion being curved to form a relatively gentle bend in the tear portion as the lever portion initiates rupture of the line of weakness.

8. An easy-opening container wall as defined in claim 6 wherein said line of weakness defines a tear portion having a relatively narrow leading end, said attachment means being located at said leading end, said lever portion of said tab defining first and second fulcrum ends engageable with the container wall outside of the tear portion and on opposite sides of the attachment means.

9. An easy-opening container as defined in claim 6 wherein said lever portion has a nose end adjacent said means for attaching, said nose end substantially overlies a region of said line of weakness and said lever portion lies substantially within the area of said tear portion.

10. A tab of the type attachable to a tear portion of an easyopening container wall wherein a line of weakness in the container wall defines the tear portion, said tab comprising:

a first lever portion attachable to the tear portion at a first location on said lever portion, said lever portion having a fulcrum engageable with the container wall and a liftable region with said first location lying closely adjacent said fulcrum;

a second lever portion having a bearing region engageable with the container wall, a handle end remote from said bearing region and a fulcrum intermediate said bearing region and said handle end; and

means for connecting said liftable region of said first lever portion to said fulcrum of said second lever portion to permit pivotal movement of the second lever portion, the handle end lying on the same side of said liftable region as said first location, whereby movement of said handle end of said second lever portion away from the container wall pivots said second lever portion about said fulcrum thereof to cause said bearing region to move along said container wall with consequent lifting of said fulcrum of said second lever portion and said liftable region, the lifting of said liftable region of said first lever portion as a result of pivotable movement of said second lever portion being insufficient to initiate severance of the line of weakness, said line of weakness being rupturable by said first lever portion in response to an upward pulling force on said second lever portion following the pivotable movement of said second lever portion about the fulcrum thereof.

11. A tab attachable to a tear portion of an easy-opening container wall to initiate severance of the tear portion from the container wall comprising:

a lever portion of plastic sheet material, one end portion of the lever portion being attachable to the tear portion adjacent the periphery of the tear portion, said lever portion extending away from said one end portion to define a lifting portion, said lever portion having integral stiffening means for making said lever portion substantially longitudinally rigid;

a gripping element of plastic sheet material; and

a connecting portion of plastic material for integrally joining the gripping element to the lifting portion of said lever portion, said gripping element at least partially being in substantially the same plane as said lever portion and extending from its juncture with the lever portion generally in the direction of said one end portion of said lever portion said gripping element having an end remote from said juncture to which a force may be applied to cause said lever portion to apply a force to the tear portion tending to initiate removal thereof.

12. A tab as defined in claim 11 wherein said connecting portion defines a hinge which permits the gripping element to pivot relative to the lever portion.

13. A tab of the type attachable to a tear portion of an easyopening container wall to initiate severance of the tear portion from the container wall comprising:

a lever portion of sheet material having integral means for stiffening the lever portion, said lever portion having an attachment location at which the lever portion can be attached to the tear portion, said lever portion extending away from said attachment location to define a lifting region;

a gripping element of sheet material, said gripping element having a first end and a connecting location adjacent the other end thereof;

means for interconnecting the lifting region of the lever portion to the gripping element to permit relatively easy movement of said gripping element relative to said lever portion in a direction tending to move the said first end of the gripping element away from the container wall;

the gripping element being manually pullable to initiate severance of the line of weakness by lever action of said lever portion; and

the sheet material at said other end of said tab 'being deformed to define a forming section for preventing the lever portion from forming a relatively sharp bend in said tear portion during severance of the line of weakness 14. A tab as defined in claim 13 wherein the sheet material at said other end of said tab is bent away from the tear strip to define the forming section.

15. A tab attachable to a tear portion of an easy-opening container wall to initiate severance of the tear portion from the container wall comprising:

a lever portion of sheet material adapted to overlie a region of the container wall, said lever portion having integral stiffening means for stiffening the lever longitudinally;

an attachment portion of sheet material attachable to the tear portion and connected to said lever portion adjacent one end of the lever portion to permit generally pivotal movement of said lever portion relative to said attachment portion;

said lever portion having a fulcrum adjacent said one end of said lever portion; and

a gripping element attached to said lever portion adjacent the other end thereof, said gripping element having an end remote from the juncture of said gripping element and said lever portion which movable with relative ease away from the container wall to facilitate manual gripping of the gripping element whereby an outward pulling force on said gripping element pivots said lever portion and causes the fulcrum to forcibly bear on the container wall with consequent severance of the tear portion from the container wall 16. A tab as defined in claim 15 wherein the tab is integrally constructed of a single piece of sheet material and said gripping element is integrally joined to the lever portion by a pliable region of sheet material.

17. A tab as defined in claim 11 wherein said one-end portion has an aperture therein, said tab including a reinforcing member joined to said lever portion of plastic material and surrounding said aperture to strengthen the region around said aperture.

Claims

1. A one-piece tab of the type attachable to a tear portion of an easy-opening container wall to initiate severance of the tear portion from the container wall comprising: a lever portion of sheet material having integral means for stiffening the lever portion, said lever portion having an attachment location at which the lever portion can be attached to the tear portion, said lever portion extending away from said attachment location to define a lifting region; a gripping element of sheet material, said gripping element having a first end and a connecting location adjacent the other end thereof, at least portions of said gripping element and said lever portion being in substantially the same plane; a pliable connecting portion of sheet material for integrally interconnecting the lifting region of the lever portion to the connecting location of the gripping element, said connecting portion being bendable to permit substantially unrestricted pivotal movement of said gripping element relative to said lever portion in a direction tending to move the first end away from the container wall, said first end of said gripping element lying on the same side of said connecting portion as said attachment location; and the gripping element being manually pullable to move the lifting region of the lever portion away from the container wall to initiate severance of the line of weakness of lever action of said lever portion.

5. A one-piece tab of the type attachable to a tear portion of an easy-opening container wall to initiate severance of the tear portion from the container wall comprising: an elongated lever portion of sheet material having integral means for stiffening the lever portion, said lever portion having an attachment location at which the lever portion can be attached to the tear portion, said lever portion extending away from said attachment location to define a lifting region; a gripping element of sheet material, said gripping element having a first end and a connecting location adjacent the other end thereof, said gripping element having a finger-receiving opening, at least portions of said gripping element and said lever portion being in substantially the same plane; a pliable connecting portion of sheet material for integrally interconnecting the lifting region of the lever portion to the connecting location of the gripping element, said connecting portion being bendable to permit substantially unrestricted pivotal movement of said gripping element relative to said lever portion in a direction tending to move the first end away from the contaiNer wall; and the gripping element being manually pullable to move the lifting region of the lever portion away from the container wall to initiate severance of the line of weakness by lever action with the sole lever action being derived from said lever portion.

6. An easy-opening container wall comprising: a container wall of sheet material having a line of weakness therein defining a tear portion at least partially removable therefrom; a tab constructed of sheet material and having a lever portion and a handle portion integrally joined by a connecting portion of sheet material, said handle portion at least partially being in substantially the same plane as said lever portion, said lever portion having an attachment location and said handle portion having an outer end; means for attaching said lever portion at said attachment location to said tear portion adjacent said line of weakness so that said tab overlies the container wall; said lever portion extending away from said attachment location to define a lifting region of said lever portion, said connecting portion integrally joining said handle portion to said lever portion at said lifting region, said outer end of said handle portion lying on the same side of said connecting portion as said attachment location; and said connecting portion being bendable to permit movement of said outer end of said handle portion a substantial distance away from said container wall with consequent pivotal movement of said handle portion relative to said lever portion to thereby expose said handle portion for easy manual gripping thereof, such pivotal movement of said handle portion being incapable of causing said lever portion to rupture said line of weakness whereby pulling outwardly on said handle portion following the pivotal movement thereof lifts said lifting region of said lever portion sufficiently to cause said lever portion to rupture said line of weakness.

10. A tab of the type attachable to a tear portion of an easy-opening container wall wherein a line of weakness in the container wall defines the tear portion, said tab comprising: a first lever portion attachable to the tear portion at a first location on said lever portion, said lever portion having a fulcrum engageable with the container wall and a liftable region with said first location lying closely adjacent said fulcrum; a second lever portion having a bearing region engageable with the container wall, a handle end remote from said bearing region and a fulcrum intermediate said bearing region and said handle end; and means for connecting said liftable region of said first lever portion to said fulcrum of said second lever portion to permit pivotal movement of the second lever portion, the handle end lying on the same side of said liftable region as said firsT location, whereby movement of said handle end of said second lever portion away from the container wall pivots said second lever portion about said fulcrum thereof to cause said bearing region to move along said container wall with consequent lifting of said fulcrum of said second lever portion and said liftable region, the lifting of said liftable region of said first lever portion as a result of pivotable movement of said second lever portion being insufficient to initiate severance of the line of weakness, said line of weakness being rupturable by said first lever portion in response to an upward pulling force on said second lever portion following the pivotable movement of said second lever portion about the fulcrum thereof.

11. A tab attachable to a tear portion of an easy-opening container wall to initiate severance of the tear portion from the container wall comprising: a lever portion of plastic sheet material, one end portion of the lever portion being attachable to the tear portion adjacent the periphery of the tear portion, said lever portion extending away from said one end portion to define a lifting portion, said lever portion having integral stiffening means for making said lever portion substantially longitudinally rigid; a gripping element of plastic sheet material; and a connecting portion of plastic material for integrally joining the gripping element to the lifting portion of said lever portion, said gripping element at least partially being in substantially the same plane as said lever portion and extending from its juncture with the lever portion generally in the direction of said one end portion of said lever portion said gripping element having an end remote from said juncture to which a force may be applied to cause said lever portion to apply a force to the tear portion tending to initiate removal thereof.

13. A tab of the type attachable to a tear portion of an easy-opening container wall to initiate severance of the tear portion from the container wall comprising: a lever portion of sheet material having integral means for stiffening the lever portion, said lever portion having an attachment location at which the lever portion can be attached to the tear portion, said lever portion extending away from said attachment location to define a lifting region; a gripping element of sheet material, said gripping element having a first end and a connecting location adjacent the other end thereof; means for interconnecting the lifting region of the lever portion to the gripping element to permit relatively easy movement of said gripping element relative to said lever portion in a direction tending to move the said first end of the gripping element away from the container wall; the gripping element being manually pullable to initiate severance of the line of weakness by lever action of said lever portion; and the sheet material at said other end of said tab being deformed to define a forming section for preventing the lever portion from forming a relatively sharp bend in said tear portion during severance of the line of weakness.

14. A tab as defined in claim 13 wherein the sheet material at said other end of said tab is bent away from the tear strip to define the forming section.

15. A tab attachable to a tear portion of an easy-opening container wall to initiate severance of the tear portion from the container wall comprising: a lever portion of sheet material adapted to overlie a region of the container wall, said lever portion having integral stiffening means for stiffening the lever longitudinally; an attachment portion of sheet material attachable to the tear portion and connected to said lever portion adjacent one end of the lever portion to permit generally pivotal movement of said lever portion relative to said attachment portion; said lever portion having a fulcrum adjacent said one end of said lever portion; and a gripping element attached to said lever portion adjacent the other end thereof, said gripping element having an end remote from the juncture of said gripping element and said lever portion which movable with relative ease away from the container wall to facilitate manual gripping of the gripping element whereby an outward pulling force on said gripping element pivots said lever portion and causes the fulcrum to forcibly bear on the container wall with consequent severance of the tear portion from the container wall.

16. A tab as defined in claim 15 wherein the tab is integrally constructed of a single piece of sheet material and said gripping element is integrally joined to the lever portion by a pliable region of sheet material.