US3281007A

US3281007A - Container closure devices

Info

Publication number: US3281007A
Application number: US424352A
Authority: US
Inventors: Adolph S Dorosz
Original assignee: United Shoe Machinery Corp
Current assignee: United Shoe Machinery Corp
Priority date: 1965-01-08
Filing date: 1965-01-08
Publication date: 1966-10-25
Anticipated expiration: 1983-10-25
Also published as: GB1136929A; FR1465829A; SE308995B

Description

Oct. 25, 1966 A. s. DOROSZ 3,281,007

CONTAINER CLOSURE DEVICES Filed Jan. 8, 1965 3 Sheets-Sheet 1 Figl InI/en for flooZp/z 5f Dorosz Oct. 25, 1966 A. s. DOROSZ 3,281,007

CONTAINER CLOSURE DEVICES Filed Jan. 8, 1965 5 Sheets-Sheet 2 Oct. 25, 1966 A. s. DOROSZ 3,281,007

CONTAINER CLOSURE DEVICES Filed Jan. 8, 1965 3 Sheets-Sheet 5 Fig. 5

United States Patent ()1 3,281,007 CONTAINER CLOSURE DEVICES Adolph S. Dorosz, Beverly, Mass., assignor to United Shoe Machinery Corporation, Flemington, N.J., a corporation of New Jersey Filed Jan. 8, 1965, Ser. No. 424,352 21 Claims. (Cl. 220-54) The present invention relates to container closures and specifically those having tear-open features.

A number of containers, and proportionately many cans, are now available having closures, usually covers or ends, which include tear-open features. These features provide access to the containers without the necessity to rely on separate container or can openers, keys, or similar expedients. The primary contribution then of these features, is one of convenience.

Closures and particularly can covers which include tearopen features, now available, are generally of metal construction. The metal used is for the most part aluminum; either the entire cover or the removable sections are of aluminum construction.

Metal construction in closures which include tear openable features leads to definite shortcomings. Of particular note is that a number of steps are required to manufacture the cover. The tear tab or opening lever employed ith one such cover and the actual closure part are produced separately by stamping or the like, the tab is then attached to the removable section of the closure part by riveting or a similar attaching step. Then too, the metal tear tab and/ or closure part is less than safe, causing a number of cut and injured fingers, as well as feet, the latter usually resulting after the tear-open section has been carelessly discarded.

It is the general object of this invention to provide a container closure device, for example a container or can cover, end, lid, section, part etc., having a tear-open feature and a can or other container provided with that device.

It is a more specific object of this invention to provide a container closure device having a tear-open feature which requires a minimum number of fabricating and assembly steps in its manufacture.

It is another more specific object of this invention to provide a container closure device having a tear-open feature which is safer to use and to dispose of than those devices presently known.

These and other objects may be attained in the present invention which is a container closure device having a tear-open feature and a container provided with the device. The container closure device of the present invention may be produced in a single step or operation, such as casting, molding, etc., while none the less being a combination of what may be considered as three components. Specifically, the components which are combined to produce the closure of this invention are a closure structure, a tear initiating means and a tear tab.

The first component referred to, the closure structure, is formed of thermoplastic synthetic polymeric material to include a panel portion and a marginal portion. The panel portion of the structure includes a tear-openable section which is defined in outline, at least at a tear initiating end, by a line of weakness forming an angle of less than 180, with the vertex of the angle defining a tear initiating site or point. The marginal portion of the closure structure is adapted for securement with or adaption into a container. As such it may be a sealing, seaming, attachment, welding or similar location in the closure structure. It may serve to facilitate securement of the container closure device to a container, or as will be indicated later, it may serve as a location at which closing of a container is carried out, as for example when the 3,281,007 Patented Oct. 25, 1966 container closure device is other than a separate unit in a container, for example a separate cover, end, etc.

The second component, the tear initiating means, includes an essentially dihedrally shaped portion, that is, a portion which is essentially defined by a dihedral angle. This portion makes up what can be considered as at least the front portion of the tear initiating means, with the line of intersection between the sides of the shaped portion forming a leading edge or front leading edge for the shaped portion, and, in turn the tear initiating means. One end of the shaped portion is attachably combined with the closure structure while the opposing end is attachably combined With the tear tab, the latter is the third component previously referred to. The end of the shaped portion which is attachably combined with the closure structure is specifically located with respect to the closure structure, to Wit at least a leading or front part of the end of the shaped portion is attachably combined with the tear initiating end of the tear-openable section in the panel portion of the closure structure. Additionally, the front or leading part of the shaped portion of the end of the shaped portion is outlined by the angle formed by the line of weakness so that the leading edge of the shaped portion leads to or intersects the tear initiating site defined by the vertex of the angle of less than formed by the line of the weakness provided in the closure structure.

By describing the portion of the tear initiating means as being essentially dihedrally shaped, or, having essentially a dihedral shape, it is intended that the shape may be somewhat deformed such as is the result when the sides of the shape do not form entirely plane surfaces. For example, the sides may be concave or convex in nature. In addition that description is intended to include a number of more specific shapes for example, dihedron, prismatic, prismoidal, truncated pyramidal, truncated trihedral and similar other shapes. The leading edge or line of intersection of any of these shapes or shaped portions may be placed in a particular angular relationship with respect to the closure structure and similarly with the tear initiating site located in the closure structure through exercise of variables available to each of the shapes or by tilting them in various ways, or as in the case of the truncated pyramidal and truncated trihedral shapes by providing them in regular or inverted relationship with respect to the closure structure. The preferred shape for the front portion of the tear initiating means is truncated pyramidal, which is in inverted relationship with the closure structure. For convenience, the description which follows will for the most part be in terms of that preference.

Preferably then, the second component, the tear initiating means, includes a truncated pyramidal shaped portion, or front portion which is in inverted relationship with respect to the closure structure. Its combination with the closure structure is effected by attaching or integrating at or through the smaller end of the truncated pyramidal shaped portion at a specific location on the tear-openable section of the panel portion of the closure structure. More specifically preferably, the location of the tear initiating means is such that at least a leading portion of the smaller end of the truncated pyramidal shaped portion is at least in effect outlined by the angle of lessthan 180 formed by the line of weakness. This combination provides in effect angles on multi-planar surfaces which intersect at the tear initiating point of the tear-openable section referred to. As a result a high concentration of stress may be conveniently obtained in the material located at the tear initiating point, the stress being transmitted to the tear initiating means by the tear tab. The provision, by which multiplanar which includes biplanar, stress concentration may be had at the tear initiating point serve greatly to facilitate easy opening and to do so with retention of effective closure or content containment by the closure device.

The third component, the tear tab, is attached to that end of the tear initiating means which is opposite to that to which the closure structure is'attachably combined. When the tear initiating means includes an inverted truncated pyramidal shaped portion, as preferred, the tear tab is attached to the larger base of that shaped portion. In doing so the tear tab may be attached in a number of different alignments with respect to the longitudinal, lateral and vertical axes of the tear initiating means. By positioning the tear tab so that it overlies the closure structure and is cantilevered or projects beyond or forward of the tear initiating point it allows stress to be very conveniently introduced to the tab, manually or otherwise, from which it is then transmitted through the tear initiating means to the tear initiating site in the closure structure.

When single step production of the container closure of this invention is desired, and, it is the preferred procedure, thermoplastic synthetic polymer materials are used in the formation of all three components. Single step molding in a single mold may then be carried out to manufacture the closure. Similarly, safety in use and disposal of closure device, and/ or its components may be had, by forming all the components from thermoplastic synthetic polymeric materials. Thermoplastic synthetic polymeric material which can be used for the purpose of this invention include for example homopolymers and copolymers of polyvinyl chlorides and polyvinylidene chlorides as well as homopolymers and copolymers of polyolefins such as the polyethylenes, polypropylenes, etc. also various homopolymers and copolymers of polystyrenes, polyacrylates and the like, also cellulose acetate and other cellulose based polymeric materials, as well as polyesters and polyamides, etc. may be used. Of these the polyvinyl chlorides and polyethylenes are presently preferred because they may be conveniently obtained having a combination of relatively low shear stress and good film strength properties. The final choice however, will depend on a number of considerations, among them the nature of the contents which are to be carried in the container to be fitted with the container closure device of this invention.

In order to further illustrate the present invention, the following drawings are included in which:

FIG. 1 is a top view, of an embodiment of the container cover of the present invention;

FIG. 2 is a bottom view of the container cover shown in FIG. 1;

FIG, 3 is a side view in section and magnification taken along the lines III-III of FIG. 1; FIG. 4 is a fragmentary side elevation, in section, of an embodiment of a container cover of this invention illustrating specific structural details;

FIG. 5 is another fragmentary side elevation, in section, of an embodiment of a container cover of this invention illustrating specific structural details;

FIG. 6 is still another fragmentary side elevation, in section, of an embodiment of a container cover of this invention illustrating specific structural details;

FIG. 7 is an exploded perspective View of an embodiment of this invention in which a container cover is attached to a container;

FIG. 8 is an exploded, perspective, partial view in magnification with parts broken away and in section illustrating an embodiment of this invention, but limited to certain parts of the same;

FIG. 9 is a fragmentary side view in section and magnification of an embodiment of the container cover of this invention illustrating specific structural details of the same;

FIG. 10 is also a fragmentary side view in section and magnification of an embodiment of the container cover of this invention illustrating specific structural details of the same;

FIG. 11 is a perspective view of an embodiment of this invention in which a closure device is included in the body portion of a container;

FIG. 12 is a perspective view of another embodiment of this invention in which a closure device is included into the body portion of a container; and

FIG. 13 is a bottom view of another embodiment of a container cover of this invention.

Reference will now be made to the drawings. One embodiment of the invention, a container closure and more specifically a cover, but including some variations is shown in FIGS. 1-10. As shown particularly in FIGS. 1-3, the container closure device, or cover 10 of this invention includes the combination of a closure structure 12, a tear initiating means 14 and a tear tab 16.

The closure structure 12 as shown, is a relatively thin web, film or sheet, etc. instance .003 to .060 in thickness, cast or molded from thermoplastic synthetic polymeric material, instance polyethylene or polyvinyl chloride. It includes a panel portion 18 and extending outward thereof a marginal portion 20. Marginal portion 20 is' shown adapted for securement with a container 22 in the manner shown in FIG. 7, and, in order to facilitate that a channel 24 is formed by or provided in marginal portion 20, see for example FIGS. 3-6 and 9 and 10.

Panel portion 18 includes a tear-openable section 26. As shown, substantially the entire of section 26 is outlined or defined by a line of weakness 28 taking the form of a scoring, indentation, etc., see particularly FIG. 2. It is preferable that the line of weakness 28 outline the tear initiating end 30 of section 26, see FIGS. 2 and 7 for a definition of tear initiating end 30. However, by extending the scoring 28, in the manner shown, predetermination of the direction and extent of tearing, after initiation is had.

At tear initiating end 30 of tear-openable section 26 the line of weakness 28 defines the same to form an angle of less than 180. FIG. 7 illustrates the angle as angle a. It is preferred that that angle be an acute angle and again beyond that angle ranging 10 to As shown, the angle is deformed as a result of the line of weakness 28 having an arcuate lineation and more precisely is shown arced inwardly. The angle may also be formed between the line of weakness 28 which is in straight lineation or it may be outwardly arced fashion. The vertex of the angle defines or forms a tear initiating site 32, at which point tearing initiates and from which point tearing follows the line of weakness 28, allowing tear initiating end 30 and eventually tear-openable section 26 to be partially or entirely displaced or removed from the remainder of panel portion 18. Parenthetically, the tear initiating site 32 may cover some small area and, as a consequence it should not be interpreted in purely geometric manner with respect to a point or vertex. Thus, the term vertex is to be construed as covering an area and not necessarily a discernible line of intersection. However, the extent to which displacement of tearopenable section 26 is to be carried out may be determined by the configuration and the extent to which the line of weakness 28 takes with respect to panel portion 18.

The line of weakness 28 may be conveniently effected as shown by use of a scoring or score line, again 28. Expedients other than scoring can also be used to effect the same purpose. Score line 28 may be located in the bottom surface 34 of panel portion 18, see FIG. 2, for example. Bottom surface 34 is opposite to surface 36 from which tear initiating means 14 projects, see FIG. 3, and in accordwith that, surface 36 may be considered as a top surface. The line of weakness 28 may also be in the form of a score line 28a located at top surface 36, see FIG. 3. Various combinations as to the location of the line of weakness28 with respect to both

surfaces

34 and 36 may also be practiced; for instance it may be formed between a pair of local reinforcing ribs 38 as shown in FIGS. 4 and 6. Parenthetically, local reinforcing ribs 38 may be used to serve as indicated, that is, to provide local reinforcement, and to allow panel portion 18 and closure 12 to be of relatively thinner cross-section if desired; also, ribs 38 may serve to locate a line of weakness 28. In general, using polyethylene or polyvinyl chloride material it is suggested that good tearing results may be obtained when the cross sectional thickness of the material in the scoring 28 is about one half the cross-sectional thickness of the material in the remainder of closure structure 12. This, however, may vary considerably and may be determined by the properties of the particular thermoplastic polymeric synthetic material which is used together with the types and nature of the local reinforcing ribs 38 which are used. In this regard note the comparative thickness in material shown in FIGS. 4-6. Specifically note the difference in thickness of the material of panel portion 18 of FIG. 5 when compared to that in FIGS. 4 and 6.

Tear initiating means 14 is attachably combined to closure structure 12. Specifically, the attachment is to the tear initiating end 30 of tear-openable section 26 of panel portion 18. In the unitary construction shown, that is, when closure device is produced in a single step molding or the like, tear initiating means 14 is integrated with or of unitary construction with tear initiating end 30, see for example, FIGS. 9 and 10 where tear initiating means 14 is in the form of a unitarily constructed upward projection of tear initiating end 30. In that type of construction, which is desirable in that it facilitates manufacture, the tear initiating means 14 is produced from the thermoplastic synthetic polymeric material used in forming closure structure 12. Other materials as well as means for attaching the two members may be used if desired but their use may be considered as contributing complication to the manufacture and structure of closure device 10.

As shown, tear initiating means 14 includes a truncated pyramidal shaped portion 14a located at what can considered as the front of the initiating means 14, see specifically FIGS. 7 and 8. The truncated pyramidal shaped portion 14:: is principally defined by or between

faces

40 and 42; and, by the line of intersection 43 formed between

faces

40 and 42, see FIG. 3.

Faces

40 and 42 may be considered as front faces and the line of intersection 43 may be considered as the leading or front edge, again see FIG. 3. Truncated pyramidal shaped portion 1411 as shown may also be characterized as being prow shaped, or as having an inverted plough shape. Note also, in this regard, that the tear initiating means 14 may itself actually be or may be considered as being of truncated pyramidal shape, however, it is the front portion 14a, defined at least in part by

faces

40 and 42 and by line 43 which is considered as forming the truncated pyramidal shaped portion 14a; see in particular FIG. 8.

With relationship to shaped portion 14a, the pyramidal shape is considered to be the triangular based type. This perspective is established with reference to back line 45 provided arbitrarily to extend between

faces

40 and 42 at some point or points to the back or rear of the line of intersection 43, again see FIG. 8. Another back line or back lines could be chosen for shaped portion 14a to give that portion the perspective of truncated pyramidal shape which is of the rectangular, etc. or other polygon based type. This same situation obtains when the front portion 14a is of essential dihedral shape other than the truncated pyramidal type.

As previously indicated the front portion 14a of tear initiating means 14 may have a deformed essentially dihedrally shaped, and as illustrated a deformed truncated pyramidal shape, if, for example, faces 40' and 42 are provided with longitudinally oriented convex contour. In the embodiment shown this shape is actually deformed in that faces 40 and 42 have a longitudinally oriented concave contour. The pyramidal shaped portion 14a as shown, includes a smaller end 44 and a larger end 46.

Ends 44 and 46, as will become more apparent herein after, may be considered the surfaces of interconnection or attachment between the pyramidal shaped portion 14a of the tear initiating member 14 and the tear tab 16 and the panel portion 18 of the closure 12 respectively. In describing end 44 as being smaller it is not intended to indicate that actual area of end 44 is necessarily smaller than the area of opposing end 46. This is for the reason, end 44 may be located in a slanted or biased plane relative to the vertical axes of the truncated pyramidal shaped portion 14a, and as a result have greater length from which to derive a greater actual area than that of end 46. By describing end 44 as smaller and end 46 as larger then it is intended that this is to be considered in outline relative to outline dimensions as they would be projected onto or through a plane located at the particular end and normal to the vertical axis of truncated pyramidal shaped portion 14a.

To return, smaller end 44 is attachably combined with tear initiating end 30 of panel portion 18. In view of that the truncated pyramidal shaped portion 14a may be considered as being in inverted position or placement in relationship to the closure structure 12. At base 44, the

faces

40 and 42, defining the front portion of base 44, are outlined by the line of Weakness 28, particularly where the latter converges to the vertex and tear initiation site 32.

Tear tab 16 is attachably combined with the tear initiating means 14, specifically at or through the larger end 46 of the truncated pyramidal shaped portion 14a of tear initiating means 14. In the unitary construction shown, as might be the case when closure device 10 is produced in a single step molding process, tear tab 16 is integrated with tear initiating means 14, seefor example FIG. 9. In that type of construction tear tab 16 is in the form of a unitarily constructed member projecting from tear initiating means 14 see for example, FIGS. 9 and 10. With that type of construction too, tear tab 16 is preferably produced from the same thermoplastic synthetic polymeric material from which tear initiating means 14 is produced. Other materials as well as means for attaching tear tab 16 to tear initiating means 14 may be used if desired but their use may be considered as contributing complication to the manufacture and structure of closure device 10.

Tear tab 16 is shown positioned on tear initiating means 14 so that it overlies closure structure 12 and projects or is cantilevered beyond tear initiating point 32. Other shapes and alignments for tear tab 16 may be used, however, that shown is preferred in that it serves very well to facilitate manual operation of the tear tab 16. Another expedient included, which serves additionally in this purpose is the provision of a locally roughened finger engageable surface 48 located on the top surface 50 of tear tab 16.

The unitary structure which can be obtained in the closure device 10 of this invention is probably best illustrated in FIGS. 7-10. These same figures indicate how tear opening takes place; FIG. 9 indicates the situation prior to the introduction of stress to tear tab 16. When stress is introduced it is transmitted through tear tab 16, from there through tear initiating means 14 to tear initiating site 32. The tear initiating site 32 acts as a high stress or concentration point as a result of its being the situs of convergence for two angles which are located in nonplanar surfaces. The first of these angles is that formed by the line of Weakness 32 in the plane of panel portion 18 and designated on in FIG. 7. The other angle is that formed between the line of intersection 43 and panel portion 18. This angle is designated {3 in FIG. 9. It is preferred practice for both of these angles to be acute and as much so as possible. The more acute angle a is, the less weakness need be inherent in the line of weakness 28 in order for the line of weakness 28 to be conveniently tearable. Similarly, the more acute angle B is the more tearing at the tear initiation site 32 is facilitated or to state it differently, the less stress is needed to obtain tearing at tear initiating site 32. A very pracical application of this latter aspect is that the more acute angle 13 is, the less need be the strength inherent in tear tab 16. As a result tear tab 16 may be made thinner or with'less material. Otherwise cutting down on material and strength of tear tab 16 may occasion tearing in or at the tear tab 16 rather than the tear initiating site 32 with the application of stress.

As indicated in FIG. tearing is initiated by lifting tear tab 16. However, it is possible to have tearing initiated by depressing or pushing down tear tab 16. To facilitate this latter operation, tear tab 16 would need be of a construction relatively stiffer than otherwise needed. This makes it a practice of lesser preference. To return, with continued stress applied, after tearing is initiated at tear initiating site 32, tearing follows along the line of weakness 28. This may be carried out to the extent that tear openable section 26 may be displaced or removed from the remainder of panel portion 18, see FIG. 7. 1

Closure device 10, specifically cover 10 may be attached to a container 22 as indicated in FIG. 7. This can be done by relying on adhesives. Adhesive, as well as other attachment, is facilitated by the presence of channel 23 on marginal portion 20. ,If the thermoplastic synthetic polymeric material is a polyethylene it is suggested that adhesive attachment may be more easily accomplished by surface treatment of the polyethylene, using for instance, electron discharge or other expedients known to aid in this type of adhesion.

As illustrated by FIG. 11 the closure device of the present invention may be located with respect to the body portion 60 of a container 62, the latter being also provided with

ends

64 and 66. As shown there, body portion 60 is formed of thermoplastic synthetic polymeric material and, may be considered as the closure structure in which a panel portion 67 having tear-openable section 68 is located. The marginal portion, or portions, not shown or legended, of the closure structure may be considered as acting as the attachment locations for

ends

64 and 66. In a variation, not shown the marginal portion or portions may be the situs of a seam, not shown or legended for body portion 60. Tear-openable section 68 is outlined by a line of weakness 70, actually shown as a scoring. Line of weakness 70, where shown as a dotted line 70a, forms an angle serving to define or outline a tear initiating end 72 of tear-openable section 68. The vertex of that angle then forms tear-initiating site 74. Tear initiating means 76 which includes a truncated pyramidal shaped portion, not shown, or legended, is attachably combined at its smaller end, not shown or legended, but outlined by dotted line 70a, to tear initiating end 72 of section 68.

The upper, that'is, larger end, not shown, or legended, is outlined to its front by dotted line 78, and is attachably combined with tear tab 80. Top surface 82 of tear tab 80 is provided with a locally roughened finger engageable surface 84 which serves to facilitate manual opening.

The embodiment of the invention illustrated in FIG. 12 shows the closure device of this invention used in a container 90, more specifically, as a unitary part of the body 92 of the container 90. Body 92 is formed of thermoplastic synthetic polymeric material and the bottom end 94 is unitary constructed with the same, as may be obtained in a container molding process. A cover 96 is provided at the other end of container body 92. Body 92 serves here as the closure structure, having an integral panel portion 93 in which a tear openable section 98 is defined in outline by line a weakness 100. The arrangement of tear initiating means, not shown, with respect to tear openable section 98 and as well with tear tab 102 may be considered as being the same as that for similar parts in FIG. 11 described immediately above.

FIG. 13 illustrates another embodiment of a container cover 110. As shown, cover 110, which is provided with a panel portion 112 and an outwardly extending marginal portion 114, is formed of thermoplastic synthetic polymeric material. Marginal portion 114 includes a channel 116 for attachment with a container, not shown. Panel portion 112 then includes a tear-openable section 118 which is outlined by a line of weakness 120 developing into an angle designated X, at tear initiating end 122. The vertex 124 of that angle serves as a tear initiating site. A tear initiating means 124 is attachably combined to the tear initiating end 122, in the same manner as in previously described embodiments, and, in similar manner tear tab 126 is attachably combined with tear initiating means 124.

As may be determined from the foregoing description, the closure device of the present invention may take many forms, including but not limited to those illustrated and described. In addition the closure device of the present invention has broad utilization in combination with containers for the containment of a wide spectrum of materials, goods, comestibles, beverages, etc.

It will thus be seen that the objects set forth above, among those made apparent from the preceding description, are efliciently attained and since certain changes may be made in the described closure device and the closure device adapted into or combined with a container, set forth without departing from the scope of the invention it is intended that all matter contained in the above description or shown in the accompanying drawings shall be interpretedas illustrative and not in a limiting sense.

Having thus described my invention, what I claim as new and desire to secure by Letters Patent of the United States is:

1. A container closure device having a tear-open feature comprising in combination a closure structure, a tear initiating means and a tear tab, the closure structure being a unitary construction formed of thermoplastic synthetic polymeric material and including a panel portion, the panel portion including a tear-openable section defined in outline at least as to a tear initiating end thereof by a line of weakness forming an angle of less than the vertex of the angle providing a tear initiating site, the tear initiating means including an essentially dihedrally shaped portion which is attachably combined through an end thereof to the tear-openable section with at least a front part of the said end outlined by the angle formed by the line of weakness, and the other end of the essentially dihedrally shaped portion attachably combined to the tear tab.

2. A container closure device accordiing to claim 1 wherein the essentially dihedrally shaped portion has a truncated pyramidal shape.

3. A container closure device according to claim 1 wherein the container closure device is formed of polyethylene.

4. A container closure device according to claim 1 wherein the container closure device is formed of poly vinyl chloride.

5. A container closure device according to claim 1 wherein the container closure device in unitarily con structed of thermoplastic synthetic polymeric material.

'6. A container closure having a tear-open feature comprising in combination a closure structure, a tear initiating means and a tear tab, the closure structure being of unitary construction formed of thermoplastic synthetic polymeric material and including a panel portion, the panel portion including a tear-openable section defined in outline at least at a tear initiating end thereof by a line of weakness forming an angle of less than 180, the vertex of the angle providing a tear initiating site, the tear initiating means including a truncated pyramidal shaped portion attachably combined through the smaller end thereof to the tear-openable section with at least a front part of the smaller end of the truncated pyramidal shaped portion outlined by the angle formed by the line of weakness with the leading edge of the truncated pyramidal shaped portion intersecting the tear initiating site to form with the panel portion of the closure structure an acute included angle, and, the larger end of the truncated pyramidal shaped portion of the tear initiating means attachably combined to the tear tab.

-7. A container closure device according to claim 6 wherein the thermoplastic synthetic polymeric material is a polyethylene.

8. A container closure device according to claim 6 wherein the thermoplastic synthetic polymeric material is a polyvinyl chloride.

9. A container closure device according to claim 6 wherein the closure structure includes a marginal portion having a channel adapted for securement into a container.

10. A container closure device according to claim 6 wherein the line of weakness is in the form of a scoring.

11. A container closure device according to claim 10 wherein scoring is provided at a single surface of the panel portion of the closure structure.

12. A container closure device according to claim 10 wherein scoring is provided at opposite surfaces of the panel portion of the closure structure.

13. A container closure device according to claim 6 wherein the tear tab projects beyond the tear initiating site.

14. A container closure according to claim 6 wherein the tear tab is provided with a roughened area in the top surface of the same.

15. A continuous closure device according to claim 6 wherein the panel portion is provided with localized reinforcement.

16. A container closure device according to claim wherein the panel portion is provided with localized reinforcement in the form of parallel ribbing having the line of weakness located therebetween.

17. A container closure device according to claim 6 wherein the angle formed by the line of weakness at the tear initiating end of the tear-openable section is an acute angle.

18. A container closure device according to claim 6 wherein the angle formed by the line of weakness at the tear-initiating end of the tear-openable section is deformed in shape.

19. A container cover having a tear-open feature comprising in combination a closure structure, a tear initiating means and a tear tab, the closure structure formed of thermoplastic synthetic polymeric mate-rial including a panel portion and a marginal portion for securement into a container, the panel portion including a tear-openable section defined in outline at least at a tear initiating end thereof by a line of weakness forming an angle of less than 180 with the vertex of the angle providing a tear initiating site, the tear initiating means including a truncated pyramidal shaped portion attachably combined through the smaller end thereof to the tear-openable section with at least a front part of the smaller end of the truncated pyramidal shaped portion outlined by the angle formed by the line of weakness, the leading edge of the truncated pyramidal shaped portion intersecting the tear initiating site to form With the panel portion of the closure structure an acute included angle, and, the larger end of the truncated pyramidal shaped portion of the tear initiating means attachably combined to the tear tab.

20. A container closure device secured into a container, the said device having a tear-open feature and comprising in combination a closure structure, a tear initiating means and a tea-r tab, the closure structure formed of thermoplastic synthetic polymeric material and including a panel portion and a marginal portion secured into a container, the panel portion including an integral tear-openable section defined in outline at least at a tear initiating end thereof by a line of weakness forming an angle of less than with the vertex of the angle forming a tear initiating site, the tear initiating means including a truncated pyramidal shaped portion attachably combined through the smaller end of the truncated pyramidal shaped portion to the tear-openable section with at least a front part of the smaller end outlined by the angle formed by the line of weakness, the leading edge of the truncated pyramidal shaped portion intersecting the tear initiating site to form with the panel portion of the closure structure an acute included angle, and, the larger end of the truncated pyramidal shape-d portion of the tear initiating means attachably combined to the tear tab.

21. A container closure device having a tear-open feature comprising in combination a closure structure, a tear initiating means and a tear tab, the closure structure being a unitary construction formed of thermoplastic synthetic polymeric material and including a panel portion, the panel portion including a tear-openable section defined in outline as to a tear initiating end thereof by a line of weakness forming an angle of less than 180 providing a tear initiating site for said tear-openable section, the tear initiating means including a narrowed stress transmitting front portion projecting from the panel portion and outlined by said angle formed by the line of weakness, and a tear tab positioned on the front portion of the tear initiating means.

References Cited by the Examiner UNITED STATES PATENTS 3,159,303 12/1964 Betner 22054 3,163,317 12/1964 Biedenstein et al 22054 THERON E. CONDON, Primary Examiner,

G. T. HALL, Assistqnt Examiner,

Claims

1. A CONTAINER CLOSURE DEVICE HAVING A TEAR-OPEN FEATURE COMPRISING IN COMBINATION A CLOSURE STRUCTURE, A TEAR INITIATING MEANS AND A TEAR TAB, THE CLOSURE STRUCTURE BEING A UNITARY CONSTRUCTION FORMED OF THERMOPLASTIC SYNTHETIC POLYMETRIC MATERIAL AND INCLUDING A PANEL PORTION, THE PANEL PORTION INCLUDING A TEAR-OPENABLE SECTION DEFINED IN OUTLINE AT LEAST AS TO TEAR INITIATING END THEREOF BY A LINE OF WEAKNESS FORMING AN ANGLE OF LESS THAN 180*, THE VERTEX OF THE ANGLE PROVIDING A TEAR INITIATING SITE, THE TEAR INITIATING MEANS INCLUDING AN ESSENTIALLY DIHEDRALLY SHAPED PORTION WHICH IS ATTACHABLY COMBINED THROUGH AN END THEREOF TO THE TEAR-OPENABLE SECTION WITH AT LEAST A FRONT PART OF THE SAID OUTLINED BY THE ANGLE FORMED BY THE LINE WEAKNESS, AND THE OTHER END OF THE ESSENTIALLY DIHEDRALLY SHAPED PORTION ATTACHABLY COMBINED TO THE TEAR TAB.