Patent Description:
Beverage container designers have developed many proposals for producing reclosable two-piece aluminum beverage containers having stay-on tab (SOT) ecology lids (can ends) wherein a portion of the contents can be saved for consumption at a later time. In the case of beverage cans, most of these inventions have required using a variation on a combination of materials, for example a displaceable polymeric insert mounted within a pour opening which provides an initially pressure resistant seal. None of these inventions have been commercially accepted on a widespread basis.

Recently, reclosable three-piece aluminum beverage containers have become popular in the energy drink market. These containers are reclosable by utilizing a lug-type closure added to the otherwise two-piece construction of the beverage container. Similarly, the beer market utilizes a two-piece aluminum beverage container with a threaded closure.

There are few commercial innovations in the field which combine a reclosable feature with a traditional SOT beverage can end. Fewer commercial innovations combine a reclosable cover with a rivetedly attached tab such that the cover rotates with the tab. Finally, there are few known commercial innovations that add complimentary features to the can end, tab and reclosable cover to create a leak-proof, reclosable can end. One such can end, with the features of the preamble in claim <NUM>, is disclosed by patent document <CIT>.

Existing products in this space generally require added features in the can end to become suitably reclosable. These features can be difficult to manufacture and require additional machinery and processing steps, which escalate cost of production. These features can also cause confusion for the consumer when trying to reclose the beverage can end.

None of the known commercial options have the universal and lightweight appeal of the SOT can end.

The present disclosure is provided to solve the problems discussed above and other problems, and to provide advantages and aspects not provided by prior can ends of this type. A full discussion of the features and advantages of the present invention is deferred to the following detailed description, which proceeds with reference to the accompanying drawings.

One aspect of the disclosure is directed to a can end for enclosing a container body. The can end is configured to be reclosable after opening. A curl extends circumferentially about a longitudinal axis. A circumferential wall extends downwardly from a radially inner portion of the curl. A circumferential strengthening member is joined to lower segment of the circumferential wall. The circumferential strengthening member extends circumferentially about a center panel. The center panel has a public side opposite a product side. A peripheral edge defines a radially outer perimeter of the center panel. A tear panel is spaced radially inwardly from the peripheral edge and is defined by a frangible score in the public side and a non-frangible hinge segment located between terminal ends of the frangible score. A tab is attached to the center panel by a rivet of the center panel. The tab is configured to rotate about the rivet. A lift end of the tab is opposite a nose portion which overlays the tear panel in a frangible score breaking position. A tongue area of the tab has a rivet aperture through which the rivet passes to attach the tab to the center panel. A void region partially surrounds the tongue area and has a first leg extending along a first side of the tongue area and a second leg extending along a second side of the tongue area. A tab hinge extends between respective terminal ends of the first and second legs of the void region. A cover is attached to the tab and is rotatable therewith. The frangible score is breakable to form a pour opening in the center panel.

An aspect of the present disclosure is directed to a can end for enclosing a container body comprising:.

This aspect of the disclosure may include one or more of the following features, alone or in any reasonable combination. The substantially leak-proof seal may comprise a film and a fixing member between the film and a surface of the tab. The film may be produced from a metal. The metal may be an aluminum alloy. The fixing member may be an adhesive. The fixing member may be an acrylic acid compound. The tab may further comprise a rivet well wherein the rivet, the tongue area, and the void region are recess within the rivet well. The substantially leak-proof seal may be formed over the rivet well. The substantially leak-proof seal may be at least substantially liquid leak-proof. The substantially leak-proof seal may be at least substantially fluidly leak-proof. The tab may comprise an enclosed grab portion between the lift end and the rivet attaching the tab to the center panel. The grab portion may have a surface area greater than a surface area of the tear panel. The grab portion may be rotational about the rivet to cover a pour opening created by fracturing the frangible score and deflecting the tear panel. The sealer may be chosen from the group consisting of a thermoplastic elastomer and a silicon rubber. The barrier may be at least substantially liquid leak-proof. The barrier is at least substantially fluidly leak-proof. The tear panel may be defined by a frangible score in the public side and non-frangible hinge segment located between terminal ends of the frangible score. The tab may be configured to rotate about the rivet. A tab hinge may extend between respective terminal ends of the first and second legs of the void region. The can end may further comprise a continuous bead having circumferential portion adjacent the peripheral edge of the center panel and non-continuous portion radially inwardly of the circumferential portion and extending radially inwardly from the circumferential portion adjacent the frangible score. The continuous portion may have a depression adjacent the lift end of the tab in the frangible score breaking position. The rivet well may have an outer perimeter bounded by a portion of the upper side of the tab which is positioned at a height along the longitudinal axis greater than a height of the outer perimeter of the rivet well when viewed from above in the frangible score breaking position. The portion of the upper side of the tab may be circumferential and encircles the rivet well, and the seal may be formed with the portion of the upper side of the tab which extends about the rivet well.

An aspect of the present disclosure, not forming part of the current invention, is directed to a can end for enclosing a container body comprising:.

This aspect of the disclosure may include one or more of the following features, alone or in any reasonable combination. The grab portion may be rotational about the rivet to cover a pour opening created by fracturing the frangible score and deflecting the tear panel. The sealer may be configured to withstand a leakage of a contents of a container to which the can end is attached by creating a barrier between the underside of the tan and the center panel. The sealer may be circumferential through from the nose end through the lift end and back to the lift end of the tab. The sealer may be chosen from the group consisting of a thermoplastic elastomer and a silicon rubber. The barrier may be at least substantially liquid leak-proof. The barrier may be at least substantially fluidly leak-proof. The tear panel may be defined by a frangible score in the public side and non-frangible hinge segment located between terminal ends of the frangible score. A tab hinge may extend between respective terminal ends of the first and second legs of the void region. The can end may further comprise a continuous bead having circumferential portion adjacent the peripheral edge of the center panel and non-continuous portion radially inwardly of the circumferential portion and extending radially inwardly from the circumferential portion adjacent the frangible score. The continuous portion may have a depression adjacent the lift end of the tab in the frangible score breaking position.

This aspect of the disclosure may include one or more of the following features, alone or in any reasonable combination. The retainer may be rotatable about the rivet in reaction to a rotation of the tab about the rivet. The retainer may be extensible from the tab to engage the curl. The retainer may comprise a keeper configured to frictionally engage the curl to retain the tab in a desired position. The retainer may comprise a fold wherein the retainer is extensible by unfolding the retainer about the fold. The retained may be produced from an elastomer. The rivet may be offset from the longitudinal axis such that the rivet is located radially outwardly of the longitudinal axis on the center panel. The can end may further comprise a cover rotatable about the rivet to place the can end in a reclosed condition covering a pour opening formed after the fracturing the frangible score to form the pour opening. The cover may be attached to the tab.

Other features and advantages of the invention will be apparent from the following specification taken in conjunction with the following drawings.

To understand the present invention, it will now be described by way of example, with reference to the accompanying drawings in which:.

While this invention is susceptible of embodiments in many different forms, there is shown in the drawings and will herein be described in detail preferred embodiments of the invention with the understanding that the present disclosure is to be considered as an exemplification of the principles of the invention and is not intended to limit the broad aspect of the invention to the embodiments illustrated.

The present disclosure provides an at least substantially leak-proof, reclosable can end for beverage containers and the like. These can ends are produced from a metal or metal alloy and have a frangible score which is fractured to form a pour opening for drinking or pouring the contents of a container. A tab is affixed by a rivet to assist in the fracture of the frangible score. A cover is provided to reclose the pour opening. The cover, tab, and can end have structural elements that are complimentary to the opening and reclosing process.

More specifically, according to this disclosure, a can end for beverages, various fluids, preferably of low viscosity, confectionary candy, chewing gum, dry food stuffs, food supplements, etc. is produced from a metal or metal alloy. The can end has a frangible score at which, when severed or fractured, defines, together with a non-frangible hinge segment, a pour opening for drinking/pouring. A tab is staked (attached) to a center panel of the can end by a rivet. The tab can be lifted to press against a tear panel and deflect it into the container. The tab can be rotated, left or right (clockwise or counterclockwise), to engage the various parts of the can end to provide a reclosable cover for the pour opening.

The various embodiments described herein are intended to provide a leak-proof or substantially leak-proof, reclosable can end for containers. Prior to opening, when seamed, or attached, to a container body, the can end is capable of holding carbonated beverages without losing pressure. A headspace of a sealed container could be nitrogen-filled to extend shelf life.

According to a further aspect of the disclosure, a potential advantage of reclosable can ends described herein is that they can be produced from aluminum or aluminum alloys. Can ends described herein are compatible with existing seamer technology, are stackable, can be transported via existing can end transfer systems, and packaged and transported by existing equipment. Can ends described herein have promotional capabilities such as laser etching on both sides, incising, embossing, and QR codes. They can be manufactured in colored stock and printed. Grab portions of some tabs described herein have a large surface area making it easy to open without damaging fingernails. The tab is convenient for people with reduced dexterity with their hands.

The present disclosure includes a lift end of a tab configured to be lifted by a user in a typical fashion to break a frangible score, thus forming a pour opening or aperture. Once the pour opening is created, the tab can be rotated across or along an upper surface (public side) of the can end to move a cover into a position wherein it recloses the pour opening.

In an embodiment, the can end is produced from metal. The can end has a pour opening created be severing a frangible score and a tab affixed by a rivet to a public side of a center panel. The tab can be lifted to fracture the frangible score. The tab can also be rotated to engage the various parts of the can end to provide a reclosable cover for the pour opening.

A traditional stay-on-tab can end for beverages has a center panel with a pour opening. A tab is affixed by a rivet, which is integral with the center panel of the can end. The elements of the present disclosure function like the traditional stay-on-tab can end, where the tab is moved upwardly to press and break the frangible score thereby creating the pour opening. After the pour opening is created, the tab can be rotated about the rivet to reclose the can end by positioning a cover over the pour opening.

According to an embodiment, an improvement to the manner in which a tab can reclose a pour opening of a beverage container comprises a keeper feature on the tab. The tab can be rotated so a retainer (or tail) is positioned over the pour opening. A first part of the retainer is flat or planar with the can end, and a second part of the gripper tab (the keeper feature) engages a double seam of the container and can end such that the tab is latched in a reclosed position. The retainer may have an elastomer material bonded to it to assist in a leak proof, reclosable function.

According to an embodiment, a can end has an upward protrusion positioned behind a rivet (opposite a pour opening) which engages a nose (the opening end) of a tab such that a tail of the tab is leveraged against a pour opening. A tail of the tab may have an elastomer material bonded to it to assist in a leak proof, reclosable feature.

The accompanying can end for these tabs may have protrusions formed entirely or partially around the frangible score which would reduce the distortion of the lid during the breaking of the frangible aperture.

The features disclosed herein provide a structure and a process by which a tab can reclose such can ends. By creating a keeper and/or retainer feature in the tab, the tab can be rotated so the retainer portion (or tail) is positioned over the drinking aperture. A first part of the retainer being flat or planar with the can end and the second part of the retainer engaging a double seam of a container and can end such that the tab is latched in a reclosed position.

In an embodiment, the retainer may have an elastomer material bonded to it to assist in a leak proof, reclosable function.

In an embodiment, a nose of a tab and a tongue area of the tab are integrated to function as a single unit to improve tab strength and openability. A tongue form is stepped down to allow a hinge seal to be applied. This is essential for the seal application further on in the process. This seal also must be higher than a top surface of a rivet attaching the tab to a center panel of the can end, so they do not interfere with each other. The unique shape and larger tab enclosed grab portion is novel to the tab art.

In an embodiment, a manufacturing process of a tab and a seal requires forming the tab in a conversion press; feeding out the tab to a seal application station wherein a sealing material is applied to a product side of the tab; curing the sealing material; and feeding the tab back to the conversion press; and staking the tab to a can end. These processing steps may be performed in the listed sequence.

In one embodiment, a manufacturing process of a can end includes providing a standalone high-speed tab press; forming tabs retained in a web of sheet material; feeding the tabs retained in the web into a seal applicator station; applying a sealing material to the tab retained in the web; feeding the tabs retained in the web to a separate conversion press; and staking the tabs onto can ends on the conversion press. These processing steps maybe performed in the listed sequence.

In an embodiment, a method comprises running tab coils through a high speed press and then recoiling them up and feeding them straight to a conversion press with a sealing material applied and with no need to loop it back into the conversion press.

In an embodiment, a can end has a raised, in relation to a public side of the can end, V-bead. The V-bead aids in creating a seal by to close the tab downwardly against the public side of the can end and helps to improve a stability of the can end. A purpose of the V-bead is to create a contact point for the seal where a nose carry slot and the V-bead form meet. This V-bead is an important aspect for reclosing of the can end lid after a pour opening has been created by opening the can end. This point of contact pushes the tab down and applies a pressure to close out the tab as it covers the pour opening.

In an embodiment, the can end has an L-step around a circumference of a pour opening or a tear panel closing the pour opening for buckle strength and to improve openability of a frangible score which at least partially defines the pour opening prior to opening the can end.

In an embodiment, a hinge seal is formed from a foil, for example an aluminum foil or sealing film, such as an induction sealable material. The material is chosen to withstand high temperature is biaxially oriented and will not distort. The sealing film or foil can carry an adheive, epoxy, or the like on one side which will engage the tab. The sealing film or foil can be heated to activate the adhesive for attachment to the tab.

In an embodiment, a sealing material for a hinge seal comprises a thermoplastic polymer resin that has a very good temperature range -<NUM> to +<NUM> , such as PETP polyethylene. The sealing material is practically insoluble in water, strong, dimensionally stable, a good gas barrier, chemical resistant, and is widely used in the food industry. The tab is heated with a focused IR light to apply the seal. The sealing material may comprise an acrylic acid compound between <NUM>% and <NUM>% to allow the PETP to bond to the tab. The sealing material could also be cured using infrared light conduction and/or induction.

In an embodiment, a sealer is applied around and over a pour opening. The sealer may be formed from a thermoplastic elastomer. Alternatively, the sealer may be formed from a high compression liquid silicon rubber injected at high speed to a surface of the tab.

High speed application of a sealing material may be provided via Nordson EFD Piezo jetting technology. This technology can be used to apply a UV cured adhesive/sealant with 752v valve having multiple heads. A plurality of tabs retained within a strip may be fed into a sealant applying station where the sealing material is applied to an inverted tab starting at a nose area and finishing at the nose area and sealing off the carry strip.

Referring now to <FIG>, a container <NUM> having a reclosable beverage can end <NUM> is illustrated. The can end <NUM> has a center panel <NUM> separated from a seaming curl <NUM> by a circumferential wall <NUM> extending downwardly from the seaming curl <NUM> to a strengthening segment <NUM> which is joined to the center panel <NUM> (see, e.g. <FIG>). The container is typically a drawn and ironed metal can, usually constructed from a thin plate of aluminum or steel. Beverage can ends <NUM> for such containers <NUM> are also typically constructed from a cutedge of thin plate of aluminum or steel, formed into blank end, and manufactured into a finished end by a process often referred to as end conversion in a conversion press.

The can end <NUM> can be joined to a container body <NUM> by the seaming curl <NUM> which is joined to a mating curl of the container body <NUM>. The seaming curl <NUM> of the can end <NUM> is integral with the center panel <NUM> by the circumferential wall <NUM> and the strengthening segment <NUM>, typically either a generally U-shaped countersink or a fold, which is joined to a peripheral edge of the center panel <NUM>, which defines an outer perimeter of the center panel <NUM>, often through an additional strengthening feature such as a circumferential step or other circumferential wall.

The circumferential seaming curl <NUM> defines an outer perimeter of the beverage can end <NUM>. It is generally centered about a longitudinal or vertical axis <NUM>, sometimes located at a center of a rivet.

The circumferential wall <NUM> extends downwardly from a radially inner portion of the seaming curl <NUM>.

The circumferential strengthening segment <NUM> is joined to a lower segment of the circumferential wall <NUM> and extends circumferentially about the center panel <NUM>.

The center panel <NUM> has a means for opening the end <NUM>. The means for opening the can end <NUM> may include a displaceable foil closure member or, as shown in <FIG>, a tear panel <NUM> defined by a curvilinear frangible score <NUM> and a non-frangible hinge segment <NUM> which extends between terminal ends of the frangible score <NUM>. Accordingly, the hinge segment <NUM> is defined by a generally straight line between a first end and a second end of the frangible score <NUM>.

The tear panel <NUM> of the center panel <NUM> may be opened, that is the frangible score <NUM> may be severed and the tear panel <NUM> displaced at an angular orientation relative to the remaining portion of the center panel <NUM>, while the tear panel <NUM> remains hingedly connected to the center panel <NUM> through the non-frangible hinge segment <NUM> (see <FIG>). In this opening operation, the tear panel <NUM> is displaced at an angular deflection, as it is opened by being displaced away from the plane of the panel <NUM>. This deflection of the tear panel <NUM> creates a pour opening <NUM> through which the contents (solid, liquid, or gas) the container can exit a containment space of the container <NUM>. This opening sequence will often plastically deform the material of the can end <NUM>.

The frangible score <NUM> is preferably a generally V-shaped groove formed into a public side <NUM> of the center panel <NUM>. A residual is formed between the V-shaped groove and a product side <NUM> of the can end <NUM>.

The can end <NUM> has a tab <NUM> secured to the center panel <NUM> adjacent the tear panel <NUM> by a rivet <NUM> which passes through an aperture in a tongue area <NUM> of the tab <NUM> (see, e.g., <FIG>). The rivet <NUM> is formed in the typical or customary manner well known in the art of can end manufacture.

A nose portion <NUM> of the tab <NUM> overlays the tear panel <NUM> in a frangible score breaking position. During opening of the can end <NUM>, the user lifts a lift end <NUM> of the tab <NUM> to displace the nose portion <NUM> downward against the tear panel <NUM> (see <FIG>). The force of the nose portion <NUM> against the tear panel <NUM> causes the score <NUM> to fracture. As the tab <NUM> displacement is continued, the fracture of the score <NUM> propagates around the tear panel <NUM>, preferably in progression from the first end of the score <NUM> toward the second end of the score <NUM>.

As shown in, for example, <FIG> and <FIG>, the tab <NUM> has a void region <NUM> which partially surrounds the tongue area <NUM>. The void region <NUM> has a first leg extending along a first side of the tongue area <NUM> and a second leg extending along a second side of the tongue area <NUM>. The tab <NUM> comprises downwardly extending legs along the first and second sides of the tongue area <NUM> which defining a space between the public side <NUM> of the center panel <NUM> and a bottom side of the tab <NUM>. The void region <NUM>, the rivet <NUM>, and the rivet aperture may be recessed within a rivet well <NUM> as illustrated, for example, in <FIG>.

A tab hinge extends between respective terminal ends of the first and second legs of the void region. The tab <NUM> bends about the tab hinge during the opening process.

As shown in, for example, <FIG>, the tab <NUM> may have an enclosed grab portion <NUM>. The grab portion <NUM> has a surface area slightly larger than an area of the pour opening <NUM> and, consequently, a larger surface area than the tear panel <NUM>. The enclosed grab portion <NUM> of the tab <NUM> comprises an upper side <NUM> and an underside <NUM>. Once the can end is in an open condition (see <FIG>), the grab portion <NUM> can be rotated about the rivet <NUM> to position the grab portion <NUM> over the pour opening <NUM> to reclose and/or reseal the can end <NUM> after the tear panel <NUM> has been removed or deflected into the container to produce the pour opening (see <FIG>).

The can ends <NUM> disclosed herein include center panel <NUM> features that contribute to the functionality of the can ends <NUM>. One such feature is a tab deflector <NUM> (see <FIG>, and <FIG>). The tab deflector <NUM> aids in creating a seal by forcing the tab <NUM> downwardly against the public side <NUM> of the can end <NUM>. As such, the tab deflector <NUM> extends upwardly from the public side <NUM> of the can end <NUM>. The tab deflector <NUM> is an important aspect for reclosing of the can end <NUM> after the pour opening <NUM> has been created by opening the can end <NUM>. As the grab portion <NUM> is rotated over the pour opening <NUM>, the nose end <NUM> of the tab <NUM> engages the tab deflector <NUM> (see, e.g., <FIG>). This point of contact pushes the tab <NUM> down and applies a pressure to close out the tab <NUM> as it covers the pour opening <NUM>.

The tab deflector <NUM> can be a structure added to the center panel, such as an epoxy or the like but, as shown in <FIG>, <FIG>, and <FIG>, the tab deflector <NUM> is preferably a raised bead (approximately <NUM> thousandths of an inch) produced by displacing a portion of the center panel <NUM> to form a raised emboss on the public side <NUM> of the can end <NUM> and a recess on the product side <NUM> of the can end <NUM>.

In <FIG> and <FIG>, the tab deflector <NUM> is a triangular or V-shaped bead. The V-shaped bead is positioned such that a contact point between the V-shaped bead and the nose portion <NUM> of the tab <NUM> is created when the can end <NUM> is in the reclosed condition. As illustrated on the can end shell <NUM> of <FIG>, the center panel <NUM> may have two tapered guides <NUM> on opposite sides of the tab deflector <NUM> to assist the rotation of the tab <NUM> to a position engaging the tab deflector <NUM>.

In <FIG>, the tab deflector <NUM> is a crescent or kidney shaped bead. Likewise, this bead is positioned such that a contact point between the bead and the nose portion <NUM> of the tab <NUM> is created when the can end <NUM> is in the reclosed condition.

As shown in <FIG> and <FIG>, the can end has an L-step <NUM> forming a convex bead on the public side <NUM> of the center panel <NUM>, about a circumference of the center panel <NUM>, and along a peripheral edge of the center panel <NUM> adjacent the strengthening member <NUM>. A portion of the L-step <NUM> is interrupted by an indent or depression forming be a crescent-shaped a finger well <NUM> for accessing the lift end <NUM> of the tab <NUM>.

The L-step <NUM> transitions to opposing branches <NUM> of a convex bead that extend radially inwardly towards the longitudinal axis <NUM>. The opposing branches <NUM> generally follow the shape or contour of the pour opening <NUM> or a tear panel <NUM>. The L-step <NUM> and the opposing branches <NUM> preferably form a continuous structure wherein intersections of the opposing branches <NUM> with the L-step <NUM> are uniform without interruption of a beaded form. These structures are primarily for strength and/or rigidity of the can end <NUM>.

As shown in <FIG> and <FIG>, the L-step <NUM> and the opposing branches <NUM> together form a continuous bead having a circumferential portion adjacent the peripheral edge of the center panel and non-continuous portion radially inwardly of the circumferential portion and extending radially inwardly from the circumferential portion adjacent the frangible score.

Also shown in <FIG> and <FIG>, the tear panel may have a bead <NUM> to take up slack metal and improve rigidity of the tear panel <NUM>. As shown in <FIG>, this tear panel bead <NUM> can be a convex bead on the public side <NUM> of the center panel <NUM>. Alternatively, the tear panel bead <NUM> can be a down bead or down panel in the public side <NUM> of the center panel <NUM> as shown in <FIG>.

As best shown in <FIG>, to restrict fluid leakage owing to the rivet/tab assembly, a seal <NUM> is formed over the rivet well <NUM>. This seal <NUM> may take any suitable form capable of withstanding internal pressures when the tab <NUM> is in the reclosed condition over the pour opening <NUM> and preventing fluid flow from a containment space of the container <NUM> to the external environment. The seal <NUM> may comprise a foil or film member <NUM> or the like positioned over the tongue area <NUM>, including the rivet <NUM>. More specifically, the seal <NUM> covers the void region <NUM> partially surrounding the tongue area <NUM>, the rivet <NUM>, and the rivet aperture, forming a cover over the rivet well <NUM>. Structurally and spatially, the rivet well <NUM> has an outer perimeter bounded by a portion of the upper side <NUM> of the tab <NUM> which is positioned at a height along the longitudinal axis <NUM> greater than a height of the outer perimeter of the rivet well <NUM> when viewed from above in the frangible score breaking position. Thus, this portion of the upper side <NUM> of the tab <NUM> is circumferential and encircles the rivet well <NUM>. The seal <NUM> is preferably formed with this circumferential portion of the upper side <NUM> of the tab <NUM> which extends about the rivet well <NUM>. The seal <NUM> forms a barrier which is desirably at least substantially liquid leak-proof, and more desirably at least substantially fluidly leak-proof. "Substantially liquid leak-proof" is intended to encompass preventing a free flow of liquid through the pour opening when the container is tipped at angle which would otherwise cause liquid to pass. "Substantially fluidly leak-proof" is intended to encompass providing a barrier against escape of a gas release from a dissolved CO<NUM> within the contents of the container.

The foil or film <NUM> may be attached by fixing member <NUM>, such as a weld, an adhesive, an epoxy or other coating which may be curable to form attachment between the foil or film and the tab <NUM>. The foil or film <NUM> can be supplied with the fixing member <NUM> already supplied thereon, or the fixing element <NUM> can be applied between the foil or film <NUM> and the tab <NUM> during application of the seal <NUM>.

The seal <NUM> may comprise a thermoplastic polymer resin film, such as PETP polyethylene. The seal <NUM> may comprise an acrylic acid compound between <NUM>% and <NUM>% to allow the PETP to bond to the tab. The seal <NUM> may also be cured using infrared light conduction and/or induction.

Again, the seal <NUM> may comprise a film or foil <NUM>, for example and an aluminum alloy foil or a sealing film, such as an induction sealable material. The material is chosen to withstand high temperature, is biaxially oriented, and will not distort. The sealing film or foil <NUM> can carry an adheive, epoxy, or other coating on one side which will engage the tab <NUM>. The sealing film or foil <NUM> can be heated or otherwise energized to activate the fixing member <NUM> for attachment to the tab.

The foil or film <NUM> may be produced from a thermoplastic polymer resin that has a very good temperature range -<NUM> to +<NUM> , such as PETP polyethylene. The film or foil <NUM> of this type is practically insoluble in water, strong, dimensionally stable, a good gas barrier, chemical resistant, and is widely used in the food industry. The tab is heated with a focused IR light to apply the seal. The film or foil <NUM> may comprise an acrylic acid compound between <NUM>% and <NUM>% as a fixing member <NUM> to allow the PETP to bond to the tab. The seal may also be cured using infrared light conduction and/or induction.

A separate sealer <NUM> is further applied between an underside <NUM> of the tab <NUM> and the public side of the center panel <NUM>. The underside <NUM> of the tab <NUM> is the side of the tab <NUM> facing the public side <NUM> of the can end <NUM> in face-to-face relationship with the public side <NUM> of the center panel <NUM>. According to <FIG>, the sealer <NUM> is applied to an underside <NUM> of the tab <NUM>. According to <FIG>, the sealer <NUM> (shown in dashed lines) is applied to the public side <NUM> of the center panel <NUM>.

The sealer <NUM> is a circumferential member. The sealer <NUM> can be formed from a thermoplastic elastomer. Alternatively, the sealer <NUM> can be formed from a high compression liquid silicon rubber injected at high speed to a surface on the underside <NUM> of the tab <NUM>.

High speed application of material of the sealer <NUM> can be provided via Nordson EFD Piezo jetting technology. This technology can be used to apply a UV cured adhesive/sealant with a 752v valve having multiple heads. A plurality of tabs <NUM> retained within a strip could be fed into a sealant applying station where the sealer <NUM> is applied to an inverted tab <NUM> starting at, for example, the nose end <NUM> of the tab <NUM> finishing at the nose end <NUM> of the tab <NUM> and sealing off the carry strip.

The sealer is configured, as in sized, shaped, and positioned, to improve the tab's ability to withstand spillage from the containment space by creating a barrier or seal about the pour opening <NUM> with the public side <NUM> of the can end <NUM>. The barrier is desirably at least substantially liquid leak-proof, and more desirably at least substantially fluidly leak-proof. "Substantially liquid leak-proof" is intended to encompass preventing a free flow of liquid through the pour opening when the container is tipped at angle which would otherwise cause liquid to pass. "Substantially fluidly leak-proof" is intended to encompass providing a barrier against escape of a gas release from a dissolved CO<NUM> within the contents of the container.

Thus, according to one embodiment, a seal <NUM> is formed on an upper side <NUM> of tab <NUM> over one or more of the tongue area <NUM>, the rivet <NUM>, the rivet aperture, and the void region <NUM>. The upper side <NUM> of the tab <NUM> being the opposite side of the tab <NUM> in relation to the underside <NUM> of the tab <NUM>. A sealer or sealing ring <NUM> is applied to the underside <NUM> of the tab <NUM>. The sealer <NUM> engages the public side <NUM> of the center panel <NUM> of the can end <NUM> to form at least a substantially leak-proof sealed pour opening <NUM> when the can end <NUM> is in the reclosed condition as illustrated in, for example, <FIG>. "Substantially" is intended to encompass preventing a free flow of liquid through the pour opening when the container is tipped at angle which would otherwise cause liquid to pass.

A manufacturing process for forming a can end <NUM> of any embodiment of <FIG> is illustrated in <FIG>.

A conversion press <NUM> is adapted to form and stake tabs <NUM> to a can end <NUM>. The conversion press <NUM> is typically the last manufacturing process of a finished can end <NUM>. Tabs <NUM> are formed by a tab die assembly <NUM> and left retained to a strip <NUM> of metal. The strip <NUM> carrying a plurality of tabs <NUM> is fed out from the die assembly <NUM> and inverted to a sealer applicator <NUM> where the sealer <NUM> is applied to the underside <NUM> of the tab <NUM> now facing upwardly (or inverted). The strip <NUM> continues to a curing station <NUM> where the sealer <NUM> is cured, for example, by a UV infrared curing system. The strip <NUM> is inverted again and fed back into the conversion press <NUM> where each tab <NUM> is removed from the strip <NUM> and staked (attached) to a can end <NUM> by positioning the rivet aperture over the rivet <NUM> and striking the rivet <NUM> to flatten the rivet <NUM>. A tester <NUM> and inspections cameras <NUM> examine the can ends <NUM> for quality purposes as the can ends <NUM> with the tabs <NUM> staked thereon exit the conversion press <NUM>.

As the can ends <NUM> exit the conversion press <NUM>, a seal applicator station <NUM> applies the seal <NUM> over the rivet well <NUM>. This may require application of the metal foil or film and curing of the seal if necessary.

This method may further require a looping mechanism due to the speed of some steps moving faster than others. The looping mechanism allows the strip to move faster through one process, for example tab forming, than another process, for example sealer curing.

Referring to <FIG>, a schematic of a seal applicator station <NUM> is illustrated. Here, can ends <NUM>' carried by an indexing transfer belt <NUM> are aligned under a punch <NUM> and die <NUM> supported on the product side <NUM> by a lower assembly comprising a projection insertable within the rivet <NUM> product side <NUM> for support. A strip <NUM> carrying the sealing film or foil is punched by the punch <NUM> such that a disk of the sealing film or foil <NUM> is carried by the punch <NUM> and adhered thereto by a vacuum pressure PV via a vacuum port <NUM>. The disk is carried through a bridge plate <NUM> to a waiting can end <NUM>'. The disk is positioned over the rivet well <NUM>. The sealing film or foil <NUM> is then cured such that the seal <NUM> is formed over the rivet well <NUM>.

Referring to <FIG>, a more detailed schematic of a seal applicator station <NUM> is illustrated. Here, can ends <NUM>' carried by the indexing transfer belt <NUM> are aligned under the punch <NUM>, biased by a spring <NUM>, and die <NUM> supported on the product side <NUM> by the lower assembly comprising the projection insertable within the rivet <NUM> product side <NUM> for support. The strip <NUM> of sealing film or foil is clamped against the die <NUM> by a seal clamp punch <NUM> and punched by the punch <NUM> such that the disk of the sealing film or foil <NUM> is carried by the punch <NUM> and adhered thereto by a vacuum pressure PV via a vacuum port <NUM> in tubularly configured ejector <NUM>. The disk is carried through the bridge plate <NUM> to the waiting can end <NUM>'. The disk is positioned over the rivet well <NUM>. The sealing film or foil <NUM> is then cured such that the seal <NUM> is formed over the rivet well <NUM>. A stripper plate <NUM> has an aperture defined by a sharpened edge <NUM> for removing excess material from the strip <NUM> prior to and subsequent to punching.

An example of the strip <NUM> carrying a plurality of pre-cut sealing film or foil members <NUM> prior to punching is illustrated in <FIG>. The pre-cut sealing film or foil members <NUM> are held within the strip <NUM> by <NUM> carry strips <NUM>. The carry strips <NUM> are spaced by an angle α, preferably equally spaced wherein the angle α is <NUM> degrees. Adjacent the carry strips <NUM> are clamping areas <NUM>.

Alternatively, a manufacturing method of a can end includes providing a standalone high-speed tab press. The tabs are formed and retained to a strip of metal in a conventional manner. The strip with the tabs retained thereto is fed into a seal applicator station, The sealing material is applied the underside of each tab. The strip is then fed into a conversion press where the tabs are removed from the strip as each tab is staked to a corresponding can end. These processing steps maybe performed in the listed sequence.

This method may comprise the step of coiling the strip bearing the tabs retained thereto in to a coil and uncoiling the strip to feed the strip into the conversion press with the sealing material applied and no need to loop the strip back into the conversion press.

As shown in <FIG>, a tab <NUM> of the present disclosure includes a cover <NUM> configured, as in sized and shaped, to be positioned over and/or within the pour opening <NUM> to desirably preserve any remining contents within the container when the can end <NUM> is in the reclosed condition. The cover <NUM> is positioned over the pour opening <NUM> by rotating the tab <NUM> to place the cover <NUM> in the desired position over the pour opening <NUM>. This rotation of the tab <NUM> is imparted to the cover <NUM> either via the cover <NUM> having been integrally formed with the tab <NUM> during the same metal forming process or by connection of the cover <NUM> to the tab <NUM>. It follows that the cover <NUM> can also be rotated without manipulating the tab <NUM>. Relative rotational movement between the tab <NUM> and the cover <NUM> will naturally occur upon rotating one of the tab <NUM> and the cover <NUM>. The container bodies illustrated in these figures are shown for example purposes and are not intended to represent commercially available container bodies.

In one embodiment, the cover <NUM> has a shape that matches a shape of the frangible score <NUM>.

In the reclosed condition of the can end <NUM>, the cover <NUM> engages the center panel <NUM> along a region of the center panel <NUM> surrounding the pour opening <NUM>. The cover <NUM> may be located within the pour opening <NUM> between the product side and the public side <NUM> of the center panel when the can end is in the reclosed condition.

An attachment fixes the cover <NUM> to the tab <NUM>. Alternatively, the cover <NUM> can be integrally formed with the tab <NUM> during the tab forming process in a one-piece construction. Optionally, the cover <NUM> is attached with the tab <NUM> by the rivet <NUM> which passes through a rivet aperture in the tab <NUM> wherein a rivet is produced from the material of the cover <NUM>, or the rivet passes through a rivet aperture on the cover <NUM>, and the rivet is produced from the material of the tab <NUM>. Optionally, the cover <NUM> is not joined to the tab <NUM> such that it rotates independently of the tab <NUM>.

As shown in, for example, <FIG>, the pour opening <NUM> can be reclosed by the cover <NUM> by simple rotation of the tab <NUM>. A portion of the cover <NUM> is positioned and fits within a space created by beam form of the tab <NUM> configured in an inverted u-shape. However, such factors as material properties and the opening process, alone or in combination, can cause the cover <NUM> to skew in a direction parallel to the longitudinal axis <NUM> or skew due to the torque during opening. These factors can cause the cover <NUM> to improperly seat over or within the pour opening <NUM>. This could cause leakage when attempts are made to reclose the pour opening <NUM>.

Referring to <FIG>, the present disclosure provides alternative structural modifications, which, alone or in combination, reduce or eliminate the effects causing poor reclosability of the pour opening <NUM>. One of these modifications is a retainer that engages a seam of the container <NUM>, namely the plastically deformed curl <NUM> of the can end <NUM> subsequent to attachment to a container body <NUM>. The retainer <NUM> including a keeper <NUM> which is configured, as in sized and shaped, to engage and a seam <NUM> attaching a can end <NUM> to a container body <NUM> and is formed from an aperture in the retainer <NUM>.

The retainer <NUM> may be a separate member attached to the tab <NUM> and extensible therefrom as depicted in <FIG>. Here, once the cover <NUM> is positioned over the pour opening <NUM>, The retainer <NUM> can be unfolded along a crease of fold line <NUM> to bring the keeper <NUM> into contact with the seam <NUM>. This extensible retainer <NUM> can be rigid but is preferably flexible and/or stretchable, for example, produced from an elastomer, to increase its ability of the keeper <NUM> to be retained to the seam <NUM> as shown in <FIG>. In <FIG>, the keeper <NUM> is stretched or folded over the seam <NUM>. Accordingly, the extensible retainer <NUM> can be produced from a rubber, elastomer or the like.

Alternatively, as shown on <FIG>, the retainer <NUM> can be an integral member as part of the lift end <NUM> of the tab <NUM>. Here, the rivet <NUM> is offset from a center position of the center panel <NUM>, i.e., offset from the longitudinal axis <NUM>. This positioning allows the tab <NUM> to be configured, as in sized and shaped, to allow the keeper <NUM> to reach the seam <NUM> when the cover <NUM> is placed over the pour opening <NUM>. Here, the keeper <NUM> is formed from an aperture in the retainer <NUM> may include a curl of the material forming the tab <NUM> having a radius of curvature configured, as in sized and shaped, to engage and grip the seam <NUM> (see <FIG>, <FIG>, <FIG>, <FIG>). This allows the cover <NUM> to be forcibly retained over the pour opening <NUM> in the reclosed condition of the can end <NUM>.

Referring to <FIG>, the cover <NUM>, the retainer <NUM>, and the keeper <NUM> may be integrally formed as part of the tab <NUM>, forming a novel one-piece construction.

Referring to <FIG> and <FIG>, the cover <NUM> is formed on the grab portion of the tab <NUM> the lift end <NUM>. In one construction, the cover <NUM> is formed by a recess <NUM> formed in the grab portion. A sealer <NUM> is applied between a bottom surface of the tab <NUM> and the center panel <NUM>. The recess <NUM> fits within the pour opening <NUM> such that the sealer <NUM> engages the center panel <NUM> to create the reclosed condition.

The retainer <NUM> is formed from the lift end <NUM> of the tab <NUM> such that in the reclosed condition as shown in <FIG>, <FIG>, <FIG>, and <FIG>, the retainer <NUM> extends beyond an outer peripheral edge of the container <NUM>. The keeper <NUM> is located radially outwardly of the cover <NUM> and inwardly from a peripheral edge of the lift end <NUM> of the tab <NUM>. Here, the keeper <NUM> comprises an aperture formed in the retainer <NUM> and a lug <NUM> formed from the tab material partially defining a shape of the aperture and extending into a s the aperture. The lug <NUM> is configured, as in sized and shaped, to engage the curl <NUM> and retain the cover <NUM> within the pour opening <NUM> (see, e.g., <FIG> and <FIG>) and may include a downwardly curled form of the material of the tab <NUM> extending towards the center panel in the ready to open position. This allows the cover <NUM> to be forcibly retained over the pour opening <NUM> in the reclosed condition of the can end <NUM>.

The center panel <NUM> may have a concave recess <NUM> configured, as in sized and shaped, to receive the cover <NUM> therein (see <FIG> and <FIG>). This recess <NUM> allows the tab <NUM> to sit closer to the center panel <NUM> such that the tab will not be an impediment to stacking can ends <NUM> or containers <NUM>.

Referring the <FIG> and <FIG>, the tab <NUM> may comprise a bend <NUM> in the grab portion which deflects the lift end <NUM> upwardly away from the center panel <NUM>. Accordingly, the bend <NUM> is a concave bend when viewed from above the can end <NUM>. The bend <NUM> also deflects the retainer <NUM> upwardly, as well as the keeper <NUM>. As shown best in <FIG>, the bend <NUM> allows the retainer <NUM>, keeper <NUM> and lug <NUM> to extend to and over the seam <NUM> to retain the tab <NUM> in the reclosed condition. This allows the cover <NUM> to be forcibly retained over the pour opening <NUM> in the reclosed condition of the can end <NUM> (see <FIG>, <FIG>, and <FIG>).

Claim 1:
A can end (<NUM>) for enclosing a container body (<NUM>) comprising:
a curl (<NUM>) extending circumferentially about a longitudinal axis (<NUM>);
a circumferential wall (<NUM>) extending downwardly from a radially inner portion of the curl (<NUM>);
a circumferential strengthening member (<NUM>) joined to lower segment of the circumferential wall (<NUM>); and
a center panel (<NUM>) about which the circumferential strengthening member (<NUM>) extends having a public side (<NUM>) opposite a produce side (<NUM>), the center panel (<NUM>) comprising:
a peripheral edge defining a radially outer perimeter of the center panel (<NUM>);
a tear panel (<NUM>) spaced radially inwardly from the peripheral edge; and
a rivet (<NUM>);
a tab (<NUM>) is attached to the center panel (<NUM>) by the rivet (<NUM>), the tab (<NUM>) comprising:
a lift end (<NUM>) opposite a nose end (<NUM>), the nose end (<NUM>) overlaying the tear panel (<NUM>) in a frangible score breaking position;
a tongue area (<NUM>) having a rivet aperture through which the rivet (<NUM>) passes to attach the tab (<NUM>) to the center panel (<NUM>);
a void region (<NUM>) partially surrounding the tongue area (<NUM>) having a first leg extending along a first side of the tongue area (<NUM>) and a second leg extending along a second side of the tongue area (<NUM>);
a substantially leak-proof seal (<NUM>) formed over at least one of the rivet (<NUM>), the tongue area (<NUM>), and void region (<NUM>); and
a sealer (<NUM>) on an underside of the tab (<NUM>) and in face-to-face relationship with the public side (<NUM>) of the center panel (<NUM>),
wherein the sealer (<NUM>) is configured to withstand a leakage of a contents of a container to which the can end (<NUM>) is attached by creating a barrier between the underside of the tab (<NUM>) and the center panel (<NUM>),
wherein the sealer (<NUM>) is circumferential through from the nose end (<NUM>) through the lift end (<NUM>) and back to the nose end (<NUM>) of the tab (<NUM>).