Tamper evident food container with accordiated pull tab

A plastic container capable of assuming a loading state, an initially sealed state and an opened state comprises a lid including a lid rim and a base having a base rim. The lid rim sealingly engages with the base rim. A projecting portion has an accordiated section and a pull tab that projects outwardly from the lid. The accordiated section has at least one pleat. The projecting portion includes a frangible bridge. When the plastic food container is in the initially sealed state, the accordiated section has a first length and a first orientation relative to the projecting portion. When the container is in the initially sealed state and a first pulling force is applied to the pull tab, the frangible bridge ruptures. When the frangible bridge ruptures and before the lid is separated from the base, the container is in a tab-employed state in which the accordiated section springs outward and has a second length visibly longer than the first length.

CROSS REFERENCE TO RELATED APPLICATION

Not Applicable.

Not applicable.

SEQUENCE LISTING, TABLE OR COMPUTER PROGRAM ON COMPACT DISC

Not applicable.

FIELD OF INVENTION

This invention relates generally to plastic food containers. The invention is more specifically related to resealable plastic food containers having tamper evident sealing mechanisms.

BACKGROUND OF THE INVENTION

It is known to use plastic containers in the food preparation and restaurant industry to package prepared foods. The typical food container of the prior art consists of a clear or solid colored base and a clear lid. In order to maintain the quality of food contents and prevent tampering with the contents of a sealed container, it is desirable that the food container, once initially sealed, not be capable of being initially opened without visible indication of the container having been opened. To achieve this feature, container manufacturers have designed containers having integral tamper evident features. Typically, these containers consist of a lid that is hingedly attached to a base. The lid seals to the base by superposing the rim of the lid upon the rim of the base. These types of plastic containers are sold as one-piece containers and are often referred to as “clamshell” containers or packages.

In one type of hinged tamper evident container, the lid and base each have interlocking elements respectively located on or near the lid rim and base rim where the two rims meet when the container is sealed (i.e., at a non-hinged side or portion of the container). The interlocking element of the lid or base is conventionally located on a tab or flange extending from the rim of the lid or base. Either or both of the tabs are attached to their respective rims by a frangible section of plastic. When the lid and base are placed in initial sealing arrangement, the interlocking elements on or near the lid rim and base rim engage and lock together. In order to open the initially sealed container, the frangible section of one or both tabs must be ruptured so as to release the tab or tabs from the container. Because the interlocking sealing elements are located on the tabs, rupturing one or more tabs from the container disables the locking mechanism. The ruptured tab provides evidence of the container having been opened. One shortcoming with the prior art food container described above is that the interlocked tabs can be cut from the container in clean fashion using scissors or another cutting implement so as to remove any indicia of the container having had a tamper evident mechanism. Also, with many tamper evident containers, one rim (typically the lid rim) superposes over the other rim (typically the base rim) such that at least one of the rim edges is exposed and subject to manipulation. With this type of sealing arrangement and construct in plastic containers, the lid and base can be partially pried open by inserting a thin object underneath an exposed rim edge at a point on the container distal from the tamper indicator. By partially prying open the rims in this fashion, one can doctor or tamper with the contents of the apparently sealed container without activating the tamper indicator.

In view of the issues presented by incorporating a tamper evident mechanism in the meeting rims of the hinged container, some manufacturers have incorporated tamper evident features as part of the structure that forms or includes the hinge. In these containers, the container is designed to require a severance near the hinge in order to unseal (initially open) the container. This construct make the hinge a single use hinge. These containers typically employ a square-shaped hinge arrangement (as seen from the side when the container is closed) in which the flange of the lid rim extends beyond the lid rim and then near-perpendicularly connects to a vertical segment that descends down from the lid flange. The vertical segment meets an extended portion of the base flange in similar near-perpendicular arrangement. The two flanges generally run parallel to each other and by their connection to the vertical segment form three sides of a square.

Square-shaped hinge containers suffer from a variety of deficits. One is a tendency of the container not to remain fully open for purposes of filling the container. The memory of the square hinge mechanism is such that the lid tends to rotate and cover all or part of the base. Another deficit is that the squeezing action required must move two adjacent, near perpendicular sides of the hinge structure and therefore the entire hinge structure must be effectively crushed in order to break the frangible line located at the bottom outside corner of the hinge structure. Thus, in order to rupture the frangible line, a squeezing force is applied to the entire box structure of the hinge area. This extended crushing motion may require the container to be stabilized with one's other hand in order to entirely rupture the frangible section.

Other tamper evident solutions involve using tabs that when activated remain attached to the container in a deformed condition and provide visible indication of the opening of the container. U.S. Published Patent Application No. 20100181323 (Thaler) is an example of one such tamper evident solution. This reference discloses a plastic food container that includes a lid adapted for sealing arrangement with a base. The rim of the base has an undercut formation adapted to receive the perimeter flange and flange tab of the lid when the lid and base are in the sealed arrangement. The flange tab includes an undercut release mechanism that allows a user to grasp a portion of the flange tab and initially open a sealed container via the extraction of the flange tab from the undercut formation by application of a pulling force to the undercut release mechanism. The flange tab includes tamper evident means that provides visible indication that the undercut release mechanism has been utilized to initially open the sealed container. A similar suggested tamper evident mechanism for food containers is that of U.S. 20100224630 (Petlak). With this tamper evident mechanism, a pull tab extends outwardly from at least one of the base or the cover. The surface of the pull tab has a series of grooves such that when the tab is partially separated from the lid or base via a pulling force, the tab is supposed to curl. This curling is intended to provide a visible deformation, which would be a signal to an end user that the container has been opened. With the containers of Thaler and Petlak, the lid rim inserts into the base rim to seal the container and therefore the pull tab must be extracted from within the confines of the base rim. This requires a complicated tab structure, as well as a tab and base rim mating arrangement.

In view of the features and deficits of the prior art containers, there is thus a need in the art for a re-closable plastic food container that is easy for end consumers to operate; combines reliable tamper evidence and defense against prying intrusion; and that uses a minimum of material to manufacture.

SUMMARY OF THE INVENTION

The present invention satisfies the needs in the art and provides an aesthetically appealing food container that is easy to use and that is both tamper resistant and tamper evident. In this respect the present invention food container comprises a plastic food container having a lid adapted for tight sealing arrangement with a base. An embodiment plastic food container of the present invention is capable of assuming a loading state, an initially sealed state, a tab-employed state and an opened state. The embodiment plastic food container comprises a lid including a lid rim. The lid rim includes a lid rim flange. The embodiment container further includes a base that has a bottom and a base rim. A side wall extends upwardly from the bottom to the base rim. The side wall surrounds the bottom.

A lid rim is tuned for sealing arrangement with the base rim. A projecting portion projects outwardly in general horizontal fashion from the lid rim flange. This projecting portion is preferably integrally formed in the lid rim flange. The projecting portion includes an accordiated section connected to a pull tab. The accordiated section comprises at least one pleat. The projecting portion also includes a frangible bridge. When the plastic food container is in the initially sealed state the accordiated section has a first length and a first orientation. The frangible bridge ruptures upon the application of a first pulling force to the pull tab when the container is in the initially sealed state. To ensure that the frangible bridge ruptures before the lid is removed from the base, the first pulling force is less than the pulling force required to separate the lid from the base. When the frangible bridge ruptures, the accordiated section has a second length visibly longer than the first length, thereby showing that the container's opening mechanism has been deployed.

In the preferred embodiment the at least one pleat comprises two legs. Each leg has a top and bottom. The two legs converge at their tops to meet at a peak. As is more fully described herein, there are a variety of locations at which to place the frangible bridge of the projecting portion. In one embodiment, the projecting portion includes a shoulder and the frangible bridge connects the at least one pleat to the shoulder. In another embodiment, the lid rim includes a peripherally projecting lid rim flange and the projecting portion includes a shoulder. The frangible bridge connects the shoulder to the lid rim flange. In a preferred embodiment, the base rim includes a base rim projecting platform and when the container is in the initially sealed state the projecting portion superposes over the base rim projecting platform. In a further embodiment, wherein when the frangible bridge ruptures, the accordiated section has a second orientation.

The benefits of the inventive container can be achieved with a projecting portion having only one frangible bridge. However, for optimum balance and symmetry it is preferable that the projecting portion have a first frangible bridge and a second frangible bridge. The first frangible bridge and the second frangible bridge rupture upon the application of a first pulling force to the pull tab when the container is in the initially sealed state. The first pulling force is less than a second pulling force required to separate the lid from the base. When the first frangible bridge and the second frangible bridge rupture, the accordiated section has a second length visibly longer than the first length. The invention is also directed to the projecting portion described above, which in the preferred embodiment has two frangible bridges connecting its shoulders to the flange of the lid rim.

Notably, in the loading or initially sealed container state, the accordiated section is in fixed position relative to the shoulders of the projecting portion. In this formation, the accordiated section has a first length. The accordiated section also preferably has a first orientation, which, again, for patency purposes is most noticeable when viewed relative to both the projecting portion and the base of the container. In particular, in a preferred embodiment, the bottom of the pleat legs of the accordiated section are flush with and aligned in the same plane as the projecting portion resulting in the accordiated section having a low angle upward deviation from the base. When the base includes a projecting platform disposed underneath the projecting portion, the proximity of the projecting platform provides another visual gauge by which to discern the orientation of the pull tab and accordiated section.

Furthermore, when the lid is sealed to the base to effect the initially sealed state, the lid rim and base rim tightly engage to seal the container. In terms of sealing arrangements, the inventive container is embodied in several versions in which the lid rim and base rim engagement structures vary. In one embodiment, the lid rim flange projects into an inner wall of the base rim and is protected from access. In another embodiment, the base rim has a base rim bead that includes a bead top segment as is known in the art. In the sealed state, the lid rim flange rests atop the bead top segment of the base rim. However, the top surface of the bead top segment includes an upwardly projecting guard bead that continuously surrounds the lid rim flange except for the portion at which the projecting portion on the lid rim flange projects horizontally outwardly such that the projecting portion can sit atop the base rim bead and be grasped by a user. In another embodiment, the bead top segment includes a base rim flange. In the initially sealed state, the lid flange superposes over the base rim. The lid rim is accessible, however, because the lid rim flange is very short (effectively ungraspable without use of a gripping tool like pliers) and the rims have a very tight engagement in which the short lid flange lies flush against the base rim, there is no way to grasp the lid except by the pull tab connected to the accordiated section.

In all embodiments, the first frangible bridge and the second frangible bridge are weakened sections of plastic and thus are designed to rupture upon the application of a pulling force to the gipping tip of the pull tab when the container is in the initially sealed state. Accordingly, because the only effective way to grasp the lid when it is sealingly engaged to the base is by the pull tab, pulling on the pull tab is the only way to separate the lid from the base. However, pulling on the pull tab will cause the frangible bridges to rupture, which allows the accordiated section to expand. As the accordiated section expands, it along with the pull tab angles upwards from its original position (if not blocked by structures by the base rim as in the first embodiment hereinafter described). As shown in the figures the pull tab and accordiated section are no longer fixed and thus angle upward. That upward angular change in position also represents a different orientation with the base. This visible expansion and upward orientation of the pull tab and accordiated section provides visible indication that the container has been opened.

In contrast to the containers of Thaler and Petlak, the pull tab of the present invention container is more easily graspable as it is not surrounded by base rim structure. Also, by having an accordiated section using pleats instead of simply having ribs or grooves formed in the surface of the tab structure, the pull tab not only bends upward and changes its orientation from its fixed position, but it extends in length from that fixed position. This provides a very patent indication of the container being opened.

DETAILED DESCRIPTION

FIGS. 1-35Cdepict preferred embodiments of a present invention tamper evident plastic container1,101and201along with its preferred features. As is seen in the figures, the inventive container (whether in the embodiment of1,101or201) includes a lid2and a base3. The inventive pull tab of the present invention can be embodied in a container that does not include a hinge as is shown inFIGS. 1-14 and 16-20. Alternatively, as is shown inFIGS. 21-34, the inventive pull tab can be part of a container1that includes a hinge68located on one side of the container. In practical use, the outer surface of floor26of base3will normally rest upon a surface (such as a table top) considered horizontal in reference to the user. Thus, the directional terms “vertical” and “horizontal” and the like are used to describe the container1,101or201and its components with respect to the orientation illustrated in the figures and are employed merely for the purposes of clarity and illustration. The directional terms “inner” and “inwardly” and the like are used herein with respect to the described container to refer to directions along the directional component toward the geometric center of the container when the lid is sealed to the base. The directional term “outer” and the like are used herein with respect to the described container to refer to directions along the directional component away from the geometric center of the lid, base or the container when the lid is sealed to the base. The directional term “peripherally” is used herein with respect to the described container to refer to directions along the horizontal directional component away from the geometric center of the lid, base or the container when the lid is sealed to the base. Additionally, the terms “upward,” “downward” and the like are used to describe spatial relationships among structure when lid2of container1,101or201is sealed or closed upon the base3. For example,FIGS. 25 through 28show a third embodiment container201when container201is in an initially sealed state. In the orientation shown inFIGS. 25 through 28, lid2is vertically above base3and projecting portion6is outwardly disposed of lid rim4.

FIGS. 1-14depict a first preferred embodiment present invention tamper evident plastic container1. As is seen in the figures, the inventive container1includes a lid2and a base3that are not attached to each other through a hinge. First preferred embodiment container1is capable of assuming a loading state (FIG. 1), an initially sealed state (FIGS. 7-9), and an opened state or tab-employed state wherein the pull tab40of the projecting portion6has been employed. (FIGS. 13-14). Lid2includes lid rim4. Lid rim4includes lid rim flange9, which is preferably horizontally outwardly extending. Container1further includes base3, which has bottom (floor)26, base rim5and side wall27extending upwardly from bottom26to base rim5. Side wall27surrounds bottom26. Lid rim4is formed for sealing arrangement with base rim5. Base rim5may include base rim flange10.

As explained below, lid2is unsealed from base3through application of a sustained first pulling force to pull tab40. Upon application of a first pulling force to pull tab40one or more frangible bridges48(numbered as48a,48bin the drawings) connecting pull tab40to projecting portion6are caused to break and accordiated section41on projecting portion6expands from its original state. This is shown inFIGS. 13 and 14. It is to be noted that the figures show preferred embodiment containers and projecting portions having two frangible bridges. This is merely a preferred embodiment of the invention as the invention can be effected with one frangible bridge. Continuing to pull on pull tab40, particularly in an upward manner, results in unsealing lid2from base3. Thus, container1and pull tab40can assume a tab-employed state or arrangement prior to actually opening container1. This state is shown inFIGS. 13-14. It is to be noted that the further application of a pulling force to pull tab40after expansion of accordiated section41causes lid2to unseal from base3. Additionally, container1, after being unsealed from the initially sealed state can be re-sealed (closed). In this re-sealed state, projecting portion6and pull tab40of container1would appear as inFIGS. 13-14.

As seen in the figures, first embodiment container1comprises lid2and base3. Lid2includes cover portion33and lid rim4. Lid rim4circumferentially extends about the periphery of lid2. In the preferred embodiment, lid rim4includes lid rim bead17. Base3includes base rim5circumferentially extending about the periphery of base3. Base rim5includes base rim bead11that comprises upwardly extending inner vertical wall12, downwardly extending outer13and bead top segment14. Bead top segment14extends from top of upwardly extending inner vertical wall12to top of the downwardly extending outer wall13. Upwardly extending inner wall12includes an undercut surface configured (shaped and sized) to receive and frictionally engage lid rim flange9of lid rim4when container1is in the sealed or closed arrangement. When container1is in the sealed arrangement lid rim flange9assumes a protected position below top segment14of base rim bead11.

In the context of the first embodiment container, an embodiment pull tab40of the present invention can be seen inFIGS. 1, 6, 7, 8 and 11-14. Container1includes projecting portion6projecting outwardly from lid2, preferably from lid rim4. In the preferred embodiment, projecting portion6is integrally formed in and projects outwardly from lid rim flange9. Projecting portion6includes pull tab40that comprises accordiated section41connected to gripping tip42. Accordiated section41comprises at least one pleat43. In the depicted embodiment, pull tab40of container1has three pleats43, but could have more or less. At least one pleat43preferably comprises two legs44. Each leg44has a top45and a bottom46. Legs44converge at their tops45to meet at peak47.

First embodiment present invention container1includes projecting portion6. Projecting portion6includes at least one shoulder, but preferably has two shoulders7a,7b.FIGS. 6, 11show a preferred embodiment projecting portion6in which one or more frangible bridges48a,48brespectively connect at least one pleat43to shoulders7a,7b. This is merely an illustrative embodiment.

When container1is in the loading state or the initially sealed state, accordiated section41has a first length50a, which for visual comparison purposes can be measured relative to projecting portion6. One or more frangible bridges48a,48brupture upon the application of a pulling force to pull tab40when container1is in the initially sealed state. When one or more frangible bridges48a,48brupture, accordiated section41has a second length50bvisibly different from first length50a. In the exemplary embodiment shown inFIGS. 6 and 11, pleat43is connected to projecting portion6by two frangible bridges48a,48b.

In the embodiment shown inFIGS. 1-14, base rim5includes base rim projecting platform52. Projecting portion6constitutes a localized planar extension of peripheral projecting lid rim flange9. When container1is closed, projecting platform52helps protect projecting portion6and its integral pull tab40from compression damage or being inadvertently snagged. Gripping tip42preferably includes surface texture55to aid in holding gripping tip42. In the various depicted embodiments, surface texture55is exemplarily shown as arcuate ribs, but could include other known textures including different shaped ribs, knurling, raised bumps or letterings as shown in the drawings.

As noted, projecting portion preferably includes two shoulders, first shoulder7aand a second shoulder7b. In the embodiment shown inFIGS. 1-14, first frangible bridge48aconnects at least one pleat43to first shoulder7aand second frangible bridge48hconnects at least one pleat43to second shoulder7b. When container1is in the loading state or the initially sealed state, accordiated section41has a first length50a. When lid2is sealed onto base3, projecting portion6is forced upward by the position of base rim bead11. Base rim bead11thus contacts projecting portion6and causes it to angle upwardly, which makes pull tab40more easily graspable and give projecting portion6an upwardly angled orientation relative to platform52. First and second frangible bridges48a,48brupture upon the application of a pulling force to pull tab40when container1is in the initially sealed state. When frangible bridges48a,48brupture, pull tab40is in the tab-employed state and accordiated section41has a second length50bthat is visibly different from first length50a. In the preferred embodiment, lid rim4includes lid rim flange9and projecting portion6is integrally formed in and projects outwardly from lid rim flange9.

The one or more frangible bridges48a,48bare formed as a relatively weaker material than other portions of projecting portion6, such as pleat43or shoulders7a,7b. By virtue of being formed of weakened material, frangible bridges48a,48brupture upon the application of a first pulling force to pull tab40when the container is in the initially sealed state that does not cause lid2to separate from base3. In the depicted preferred embodiment, projecting portion6has two shoulders, first shoulder7aand second shoulder7band pull tab40is interposed between shoulders7a,7b. In the embodiment in which bridges48a,48bconnect to a portion of accordiated section41, frangible bridges48a,48bmay respectively connect to shoulders7a,7bdirectly or via a riser60as shown in the figures. When container1is in the loading state or the initially sealed state, at least one pleat43in accordiated section41is connected to projecting portion6. In the depicted preferred embodiment this connection is achieved by a first frangible bridge48aextending from pleat43to riser60on first shoulder7aand by second frangible bridge48bextending from pleat43to riser60on second shoulder7b. When the at least one pleat43is connected in such fashion, pull tab40and accordiated section41has a visible first length50aand a first orientation (substantially parallel) relative to projecting portion6. In the figures showing a preferred embodiment projecting portion6in which accordiated section41has three pleats43, each pleat43is thus bookended by a pair of risers60. Risers60are shaped similarly to a transverse cross-section of pleats43in terms of kg length and the angle between legs44. Wherever first frangible bridge48aand second frangible bridge48bare located, it is preferable that they be integrally formed in projecting portion6by thinning, scoring or skip-perforating (collectively referred to as “weakening”) the plastic extending between he structures intended to separate (pleat43and riser60in the case of the embodiment shown inFIGS. 6 and 11).

As seen in the figures, projecting portion6and its associated accordiated section41deforms by operation of expansion of pleats43and not by operation of serration-like structures such as recesses or ribs (protrusions) formed on its surface. Accordingly, it provides a very reliable and noticeable deformation both in terms of visible difference. Plus, in terms of tactile feel when the accordiated section41“pops” by virtue of the rupturing of one or more frangible bridges48a,48b. However, being of weakened material, frangible bridges48aand48brupture upon the application of a first pulling force to pull tab40when the container is in the initially sealed state. To break frangible bridges48a,48b, an outwardly directed pulling force is applied to pull tab40by way of grasping gripping tip42. Notably, as shown inFIGS. 1-14, when first frangible bridge48aand second frangible bridge48brupture upon the application of a first pulling force to pull tab40, accordiated section41has a second length50bvisibly different from first length50a. Also, a visible separation61is observable in the separated structures of pull tab40. Application of a continued or further pulling force to pull tab40after rupture of frangible bridges48a,48bresults in lid2separating from base3.

The present invention is not just directed to the container shown, but more specifically to the projecting portion6described herein. A preferred embodiment projecting portion6is integrally formed in and projects outwardly from a plastic container1. The plastic container is capable of assuming a loading state, an initially sealed state and an opened state. The container can also assume a tab-employed state in which the container lid is still sealed to the base. The projecting portion6comprises an accordiated section41connected to a pull tab40. Accordiated section41comprises at least one pleat43. Projecting portion6further includes at least one shoulder (shown in the embodiments as two shoulders7a,7b). Projecting portion6includes one or more frangible bridges48a,48b. Accordiated section41has a first length50awhen one or more frangible bridges48a,48bare intact. In the case of containers101,201of the second and third embodiment, pull tab40and accordiated section41can also have a first orientation51awhen one or more frangible bridges48a,48bare intact. Accordiated section41has a second length50bwhen one or more frangible bridges48a,48bare ruptured. Second length50bis visibly longer and different from first length50a. In the second and third embodiment containers101,201, pull tab40and accordiated section41also has a second orientation51bwhen one or more frangible bridges48a,48bare ruptured whereby second orientation51bis visibly different from first orientation51a. Also, a visible separation61is observable in the separated structures of pull tab40.

As in the case of container1, a more preferred embodiment projecting portion6includes two shoulders, first shoulder7aand a second shoulder7b. It correspondingly has a first frangible bridge48aand a second frangible bridge48b. When the inventive container in any of its embodiments is in the loading state or the initially sealed state, accordiated section41has a first length50arelative to projecting portion6. Also when the inventive container in any of its embodiments is in the loading state or the initially sealed state, pull tab40and accordiated section41has a first orientation51arelative to projecting portion6. In the case of containers101and201of the second and third embodiments respectively, accordiated section41has a first horizontal orientation51awhen frangible bridges48aand48bare intact. First and second frangible bridges48a,48brupture upon the application of a pulling force to pull tab42when container1(or101or201) is in the initially sealed state. When frangible bridges48a,48brupture, accordiated section41, and thus pull tab40, has a second length50bthat is visibly different from first length50a. When frangible bridges48a,48brupture, pull tab40and accordiated section41has a second orientation51bthat is different from first orientation51a. In the case of the second and third embodiment containers101,201the difference of the second orientation is more patent. As seen inFIGS. 16-20 and 21-34, pull tab40and accordiated section41also have a second orientation51bwhen frangible bridges48aand48bare ruptured whereby second orientation51bis markedly visibly different from first orientation51a.

FIGS. 16-20depict a second preferred embodiment present invention tamper evident plastic container101along with its preferred features. As is seen in the figures, the inventive container101includes a lid2and a base3. Second preferred embodiment container101is capable of assuming a loading state (FIG. 16), an initially sealed state (in which its projecting portion is disposed as is shown inFIGS. 17 and 18), a tab-employed state (in which the pull tab portion is disposed as is shown inFIGS. 19-20. Continuing to pull on pull tab40after the container is in the tab-employed state operates to remove the lid from the base and place the container in an opened state. Lid2includes lid rim4. Lid rim4includes lid rim flange9, which is preferably horizontally outwardly extending. Container101further includes base3, which has bottom (floor)26, base rim5and side wall27extending upwardly from bottom26to base rim5. Side wall27surrounds bottom26. Lid rim4is formed for sealing arrangement with base rim5.

As explained below, after one or more frangible bridges48a,48brupture, lid2is unsealed from base3through continued or further application of a pulling force to pull tab40. Upon application of a first pulling force to pull tab40one or more frangible bridges48a,48bconnecting pull tab40to projecting portion6are caused to break. Continuing to pull or applying a discrete second pulling force on pull tab40, (i.e., further application of a pulling force to pull tab40) particularly in an upward manner, results in unsealing lid2from base3. Thus, container101and pull tab40can assume a tab-employed state or arrangement prior to actually opening container101. This state is shown inFIGS. 19-20. Additionally, container201, after being unsealed from the initially sealed state can be re-sealed (closed). In this re-sealed state, container201would also appear as inFIGS. 19-20.

As seen in the figures, second embodiment container101comprises lid2and base3. Lid2includes cover portion33and lid rim4. Lid rim4circumferentially extends about the periphery of lid2. The overall rim structural features that make the second embodiment container not just tamper evident, but also tamper resistant are similar to those shown inFIG. 15and are described infra with respect to the third embodiment container. However, in the case of the second embodiment container, bead top segment14includes an upwardly projecting guard bead31. Guard bead31peripherally and continuously extends atop base rim bead11except for one gap (a discontinuity)64sized to allow projecting portion6to extend there through when the container is in the sealed state. Guard bead31thus serves as a barrier to accessing lid rim flange9when container101is in the sealed state.

The inventive pull tab40of the second embodiment container is identical to that of the first embodiment container and the frangible bridge or bridges can be located as is described above and shown inFIGS. 6, 11 and 35A-35C. By virtue of the rim structures utilized in the second embodiment container101, projecting portion6is not biased and held at an upward angle relative to base rim5as in the case of container1. This different rim structure allows not just the length of projecting portion6to provide a visible indicator of the pull tab40being employed, but also its orientation. In this respect, when container101is in the loading state or the initially sealed state, accordiated section41has a first length50a, which for visual comparison purposes can be measured relative to projecting portion6. Accordiated section41also preferably has a first orientation51a, which for discernment purposes can be more easily seen relative to projecting portion6and platform52of base3. One or more frangible bridges48a,48brupture upon the application of a pulling force to pull tab40when container101is in the initially sealed state. When frangible bridges48a,48brupture, accordiated section41has a second length50bvisibly different from first length50a. As explained above, projecting portion6preferably has two frangible bridges48a,48b, but the invention can be practiced with only one bridge.

In the second embodiment, base rim5includes base rim projecting platform52. When container101is in the initially sealed state, projecting portion6superposes over base rim projecting platform52. Thus, when container201is closed, projecting platform52helps protect projecting portion6and its integral pull tab40from compression damage or being inadvertently snagged. Gripping tip42preferably includes surface texture55to aid in holding gripping tip42. Platform52also serves to provide a visible reference for the orientation of projecting portion6both before and after activation of pull tab40. In this respect, accordiated section can also be formed with a strong memory such that the rupturing of one or more frangible bridges48a,48bcauses projecting portion6to have a second orientation51bvisibly different from first orientation51a. As used herein, the term “orientation” in reference to projecting portion6means its orientation relative to the angle of position of projecting platform6. In the case of second embodiment container101, the orientation of projecting platform6is generally horizontal and aligned with platform52projecting from base rim5. Platform52thus serves to emphasize and delineate the orientation of pull tab40. Thus, when frangible bridge48aruptures, the memory in accordiated section41causes at least pull tab40to angle upward and increase distance from platform52. Thus, in addition to changing the length of the accordiated section and the pull tab, the rupturing of one or more frangible bridges48a,48balso preferably causes pull tab40to visibly change orientation from first orientation51ato second orientation51bas shown inFIGS. 19-20. In the preferred embodiment, lid rim4includes lid rim flange9and projecting portion6is integrally formed in and projects outwardly from lid rim flange9.

As seen inFIGS. 16-20, pull tab40and its associated accordiated section41deforms (extends) by operation of expansion of pleats43and not by operation of serration-like structures such as recesses or ribs (protrusions) formed on its surface. Accordingly, it provides a very reliable and noticeable deformation both in terms of visible difference, plus in terms of tactile feel when the accordiated section41“pops” by virtue of the rupturing of frangible bridges48a,48b. However, being of weakened material, frangible bridges48aand48brupture upon the application of a first pulling force to pull tab40when the container101is in the initially sealed state. To break frangible bridges48a,48b, an outwardly directed pulling force is applied to pull tab40by way of grasping gripping tip42. Notably, as shown inFIGS. 16-20, when first frangible bridge48aand second frangible bridge48brupture upon the application of a pulling force to pull tab40, pull tab40and accordiated section41have a second length50bvisibly different from first length50a. In the preferred embodiment, a second orientation51bis visibly different from first orientation51a. In the preferred embodiment, second orientation51bis visibly angled upward from projecting portion6in relation to its previous parallel or flush position with projecting portion6due to being fixed by frangible bridges48a,48b.

FIGS. 21-36depict a third preferred embodiment present invention tamper evident plastic container201along with its preferred features. As is seen in the figures, the inventive container201includes a lid2and a base3attached to each other through a hinge68located on one side of the container when sealed. The third embodiment container includes the inventive projecting portion described with reference to the second embodiment container or shown in the figures.

As shownFIGS. 21-34, third preferred embodiment container201is capable of assuming a loading state (FIGS. 21-24), an initially sealed state (FIGS. 25-28), a tab-employed state (FIGS. 33-34) in which the container may still remain sealed or be opened and an opened state (FIGS. 31, 32). Lid2includes lid rim4. Lid rim4includes lid rim flange9, which is preferably horizontally outwardly extending. Container201further includes base3, which has bottom (floor)26, base rim5and side wall27extending upwardly from bottom26to base rim5. Side wall27surrounds bottom26. Lid rim is formed for sealing arrangement with base rim5.

As explained below, lid2is unsealed from base3through application of a sustained pulling force to pull tab40. Upon application of an initial pulling force to pull tab40one or more frangible bridges48a,48bconnecting pull tab40to projecting portion6are caused to break. Further application of a pulling force on pull tab40, particularly in an upward manner, results in unsealing lid2from base3. Thus, container201and pull tab40can assume a tab-employed state or arrangement prior to actually opening container201. This state is shown inFIGS. 33, 34. Additionally, container201, after being unsealed from the initially sealed state can be re-sealed (closed). In this re-sealed state, container201would appear as inFIGS. 33, 34.

As seen in the figures, third embodiment container201comprises lid2and base3. Lid2includes cover portion33and lid rim4. Lid rim4circumferentially extends about the periphery of lid2.FIG. 15depicts preferred embodiment rim structural features that make the third embodiment container not just tamper evident, but also tamper resistant. In the preferred embodiment, lid rim4includes lid rim bead17that comprises a downwardly descending lid rim inner vertical wall18, an upwardly extending lid rim outer wall19and a bead bottom segment20. Bead bottom segment20extends from the bottom21of lid rim inner wall18and curves into the bottom22of the lid rim outer wall19. Base3includes base rim5circumferentially extending about the periphery of base3. Base rim5includes base rim bead11that comprises upwardly extending inner vertical wall12, downwardly extending outer wall13and bead top segment14. Bead top segment14extends from top15of upwardly extending inner vertical wall12to top16of the downwardly extending outer wall13. Upwardly extending inner wall12includes undercut surface24configured (shaped and sized) to receive and frictionally engage outer wall19of lid rim4when container201is in the sealed or dosed arrangement. When container201is in the sealed arrangement lid rim flange9assumes a position above or on top of the top surface25of top segment14of base rim bead11. As the figures also show, lid rim4is structured such that it includes lid rim flange9connected to lid rim outer wall19. Lid rim outer wall19is of such height that lid rim flange9is positioned higher than cover portion33of lid2. As an added tamper resistance feature against prying or grasping of the lid rim, cover portion33includes one or more elongate cover beads34protruding upward from the outer surface35of cover portion33. Bead34is optimally positioned 5 millimeters or less from lid rim outer wall19to prevent grasping of lid rim flange9.

In the context of container201, the inventive pull tab40of the present invention is best seen inFIGS. 26-29, 33 and 34. Container201includes projecting portion6integrally formed in and projecting outwardly from lid2, preferably from lid rim4. In the preferred embodiment, projecting portion6is integrally formed in and projects outwardly from lid rim flange9. Projecting portion6includes pull tab40that comprises accordiated section41connected to gripping tip42. Accordiated section41comprises at least one pleat43. In the depicted embodiment, pull tab40of container201has three pleats43, but could have more or less. At least one pleat43preferably comprises two legs44. Each leg44has a top45and a bottom46. Legs44converge at their tops45to meet at peak47.

The present invention container201includes projecting portion6. Projecting portion6includes one or more shoulders7a,7b. The exemplary embodiment ofFIGS. 26-29, 33 and 34can have frangible bridges48aand48bthat can respectively connect at least one pleat43to shoulders7a,7bor can connect pull tab40to shoulders7a,7bas is shown inFIG. 35B. When container201is in the loading state or the initially sealed state, accordiated section41has a first length50a, which for visual comparison purposes can be measured relative to projecting portion6. Accordiated section41also preferably has a first orientation51a, which for discernment purposes can be more easily seen relative to projecting portion6and base3. Frangible bridges48a,48brupture upon the application of a pulling force to pull tab40when container201is in the initially sealed state. When frangible bridges48a,48brupture, accordiated section41has a second length50bvisibly different from first length50a.

In the preferred embodiment, base rim5includes base rim projecting platform52. When container201is in the initially sealed state, projecting portion6superposes over base rim projecting platform52. Projecting portion6constitutes a localized planar extension of peripheral projecting lid rim flange9. On the other hand, platform52preferably includes outer wall13to add rigidity to platform52. Thus, when container201is closed, projecting platform52helps protect projecting portion6and its integral pull tab40from compression damage or being inadvertently snagged. To aid in grasping gripping tip42, platform52may include cavity53on platform surface54. Gripping tip42preferably includes surface texture55to aid in holding gripping tip42. In the depicted embodiment, surface texture55is exemplarily shown as arcuate ribs, but could include other known textures including differently shaped ribs, knurling, raised bumps or lettering. Platform52also serves to provide a visible reference for the orientation of projecting portion6both before and after activation of pull tab40. In this respect, accordiated section can also be formed with a strong memory such that the rupturing of one or more frangible bridges48a,48bcauses projecting portion6to have a second orientation51bvisibly different from first orientation51a. As used herein, the term “orientation” in reference to projecting portion6means its orientation relative to the container's horizontal direction, which horizontal direction platform52serves to emphasize and delineate. Thus, when frangible bridge50aruptures, the memory in accordiated section41causes at least pull tab40to angle upward and increase distance from platform52.

The preferred embodiment projection portion has at least one frangible bridge, but is discussed and shown in the drawings in a preferred embodiment with two frangible bridges, which provide symmetry and balance to projecting portion6and pull tab40. Similarly, in the preferred embodiment, projecting portion includes two shoulders, first shoulder7aand a second shoulder7b. Thus, by way of example, in one embodiment, the projecting portion could include first frangible bridge48aconnecting the at least one pleat43to first shoulder7aand a second frangible bridge48bconnecting the at least one pleat43to second shoulder7b. When container201is in the loading state or the initially sealed state, accordiated section41has a first length50aand a first orientation51arelative to projecting portion6. First and second frangible bridges48a,48brupture upon the application of a pulling force to pull tab42when container201is in the initially sealed state. When frangible bridges48a,48brupture, accordiated section41has a second length50bthat is visibly different from first length50a. The rupturing of frangible bridges48a,48balso preferably causes projecting portion6to visibly change orientation from first orientation51ato second orientation51bas shown in the figures. In the preferred embodiment, lid rim4includes lid rim flange9and projecting portion6is integrally formed in and projects outwardly from lid rim flange9.

Frangible bridges48a,48bare formed as a relatively weaker material than pleat43, shoulders7a,7b, or flange9. By virtue of being formed of weakened material, frangible bridges48a,48brupture upon the application of a first pulling force to pull tab40when the container is in the initially sealed state. Ideally, this first pulling force should be significantly less than the pulling force necessary to unseal lid2from base3, though testing on prototypes indicates that it is not necessarily the peak force differences between bridge frangibility and container separability, but the amount of work that determines optimum operation. In the depicted preferred embodiment, projecting portion6has two shoulders, first shoulder7aand second shoulder7band pull tab40is interposed between shoulders7a,7b. In one embodiment, frangible bridges,48a,48beach respectively connect to shoulders7a,7bvia a riser60. When container201is in the loading state or the initially sealed state, the at least one pleat43in accordiated section41is connected to projecting portion6. In the depicted preferred embodiment this connection is achieved by a first frangible bridge48aextending from pleat43to riser60on first shoulder7aand by second frangible bridge48bextending from pleat43to riser60on second shoulder7b. When the at least one pleat43is connected in such fashion, accordiated section41has a visible first length50aand a first orientation51a(substantially parallel) relative to projecting portion6. In the figures showing a preferred embodiment projecting portion6in which accordiated section41has three pleats43, each pleat43is thus bookended by a pair of risers60. Risers60are shaped similarly to a transverse cross-section of pleats43in terms of leg length and the angle between legs44. In the depicted embodiment first frangible bridge48aand second frangible bridge48bare integrally formed in projecting portion6and can be formed by thinning, scoring or skip-perforating (collectively referred to as “weakening”) the plastic extending between pleat43and riser60.

As seen in the figures, projecting portion6and its associated accordiated section41deforms by operation of expansion of pleats43and not by operation of serration-like structures such as recesses or ribs (protrusions) formed on its surface. Accordingly, it provides a very reliable and noticeable deformation both in terms of visible difference, plus in terms of tactile feel when the accordiated section41“pops” by virtue of the rupturing of frangible bridge48aor bridges48a,48b. However, being of weakened material, frangible bridges48aand48brupture upon the application of a first pulling force to pull tab40when the container is in the initially sealed state. To break frangible bridges48a,48b, an outwardly directed pulling force is applied to pull tab40by way of grasping gripping tip42. Notably, as shown inFIGS. 33-36, when first frangible bridge48aand second frangible bridge48brupture upon the application of a first pulling force to pull tab40, accordiated section41has a second length50bvisibly different from first length50a. In the preferred embodiment, it also has a second orientation51bvisibly different from first orientation51a. In the preferred embodiment, second orientation51bis visibly angled upward from projecting portion6in relation to its previous parallel or flush position with projecting portion6due to being fixed by frangible bridges48a,48b.

In the embodiment in which the a frangible bridge connects to a pleat, it is preferred that the frangible bridge be located at the point where it can extend directly from the pleat to the shoulder. Moreover, thoughFIGS. 1-34show a preferred embodiment projecting portion6in which frangible bridges48a,48brespectively connect at least one pleat43to risers60on shoulders7a,7b, this is merely an illustrative embodiment. In alternative embodiments of projecting portion6, the one or more one frangible bridge48a,48bcould be respectively located between shoulders7a,7band pull tab40. This is shown inFIG. 35A. Alternatively, as shown inFIG. 35B, projecting portion6could comprise first proximal shoulder107a, second proximal shoulder107b, first distal shoulder108aand second distal shoulder108b. In this embodiment frangible bridge48acould be located between first proximal shoulder107aand first distal shoulder108a. A second frangible bridge48bcould be located between second proximal shoulder107band second distal shoulder108b. In tests of various pull tab and projecting portion configurations, the configuration of the projecting portion shown inFIG. 35Chas shown to work best to ensure that end users grasp the portion of the pull tab that is distal to the frangible bridges. When a user grasps beyond the gripping tip42of pull tab40of projecting portion6such that he or she grasps a portion of projecting portion6that is proximal to frangible bridges48a,48b, then it is possible that the user could pull the lid and base apart without rupturing the frangible bridges48a,48b. Thus, as is shown inFIG. 35C, a preferred embodiment container and projecting portion would have a frangible bridge extending from a shoulder7aof projecting portion6to flange9of lid rim4. In the shown preferred embodiment ofFIG. 35C, the container has a first frangible bridge48aextending from shoulder7ato flange9and a second frangible bridge48bextending from shoulder7bto flange9.

Referable toFIGS. 35A-35C, in tests of prototypes, placing of the bridge wholly in the shoulder or at its proximal end nearest the lid flange aided break consistency. Additionally, though the frangible bridge may be formed as a web extending between structures, in the preferred embodiments, the frangible bridge is a distinct point between structures. It is also preferable that the gripping tip be as distant as possible from the frangible bridges. Doing so ensures that end users grab the gripping tip and not the entire projecting portion or the entire pull tab. Additionally, though for simplicity's sake the pull tab is shown to deform in one direction, depending on how (i.e., what direction) the pull tab is pulled, the pull tab can achieve a second orientation in which it is up, down or a combination of off to a side relative to its first orientation. The key is that the pull tab is always different from the first or original orientation when the container is first loaded and closed.

A container and projecting portion constructed in accordance with the present invention can be manufactured in a variety of shapes and sizes, and is preferably formed of resins or plastic materials including, but not limited to, polyethylene, polypropylene, polyvinyl chloride, polyethylene terephthalate (“PET”) or high impact polystyrene (“HIPS”). The container is preferably thermoformed, but can be blow-molded or injection molded. The container lid and base, as well as the projecting portion, can be transparent or translucent, and may be colored in either instance. The container can be provided with vents to promote the flow of air or steam in or out of the container. Further, the container can be of any shape, including round or polygonal. As shown in the figures, the rim structures of the container may be adapted to include a hinge such that the lid and base are connected to each other in a clamshell configuration.

Having described the invention in detail, those skilled in the art will appreciate that modifications may be made of the invention without departing from its spirit. Therefore, it is not intended that the scope of the invention be limited to the specific embodiment illustrated and described.