RELATED APPLICATIONS This application is a Continuation-in-Part application of U.S. patent application Ser. No. 14/226,898 for LIGHT WEIGHT, HINGED SELF-CLOSING CONTAINER COVERS AND COMBINATION FLEX-TORSION SPRINGS FOR USE WITH SUCH COVERS filed Mar. 27, 2014 and included herein in its entirety by reference.
FIELD OF THE INVENTION The invention pertains to container covers and, more particularly, to lightweight, self-closing covers having frangible seams surrounding reclosable gates that occupy a large percentage of the area of the container cover and are supported by elastomer springs.
BACKGROUND OF THE INVENTION For many years, manufacturers of cans, particularly aluminum beverage containers have searched for a way to replace pull tab opening mechanisms ubiquitous in the beverage industry. Variations of pull tab opening mechanisms are universally used throughout the world but have two primary deficiencies. First, with some pull tab designs, the tab may fall into the beverage container and potentially become a swallowing hazard. Second, once opened, pull tab opening mechanisms are not easily resealed. Beverages, particularly carbonated beverages like beer and soft drinks, rapidly lose their effervescence as the entrained carbon dioxide is released from the beverage and passes into the air surrounding the beverage container.
Additionally, pull tab opening mechanisms typically require at least some finger/hand strength to open the container. The opening process may present difficulties to potential users who do not possess sufficient finger/hand strength.
Also, pull tab tops of the prior art require a quantity of metal, generally aluminum, that might be reduced in a better design, and are process intensive in their manufacture.
In the previously filed application included by reference, covers having relatively large reclosable gate openings (i.e., gate openings occupying 90% or more of the cover including chuck walls) have been disclosed. These covers rely on metallic combination flex-torsion springs to effect opening and reclosing thereof. These combination flex-torsion springs provide resistive and restoring forces through a combination of flexing and torsional movements. The disadvantages include cost of manufacturing and the complexity of assembly of covers that include them.
It would, therefore, be desirable to create an easily openable container cover having a large gate, and that also eliminates the possibility of any portion of the pull tab opening mechanism from detaching from the can and falling into the contents. It would further be desirable to create a reclosable cover so as to trap carbon dioxide from escaping from the beverage into the surrounding air. It would be still further desirable to make the container top lightweight to minimize the amount of metal needed to form the top and any associated spring. It would be further desirable to provide self-closing covers using elastomer springs placed either internally (i.e., within the container), or externally on the outside cover surface.
SUMMARY OF THE INVENTION In accordance with the present invention there are provided lightweight, covers for containers having self-closing gates or dome areas that are operatively connected to outer portions of the cover by an elastomer spring. Such elastomer springs may be formed from resilient materials having the necessary properties including percentage of elongation, cure methods, cure times, etc.
A unique tri-fold seam including a frangible seam portion forms a flange that works cooperatively with the elastomer spring to implement three modes of operation of the openable gates. In a first mode, after the gate is initially opened by downward directed pressure, for example a tap on the dome or gate by the heal of the palm of a user's hand, the gate returns to a reclosed orientation. Further downward pressure on the gate pushes it further into the container to which the novel cover is attached whereat a toggle operation locks the gate in the open position. An action such as swirling the container contents against the gate, overcome the toggle and the gate again returns to a reclosed orientation. Finally, if the gate is pushed even further downward, the toggle mechanism is defeated and the elastomer spring is forced past its elastic limit and the gate remains in a permanently open orientation. The novel covers in accordance with the invention may be fabricated to be compatible with current production equipment and practices. The novel covers eliminate the pull tab construction of the prior art and allow a comparable container to be produced using less material than prior art containers. Multiple designs for elastomer springs are also provided, including extremely narrow designs that allow the gate to occupy nearly 100% of the cover area inside or outside the chuck walls.
It is, therefore, an object of the invention to provide a lightweight, reclosable cover for a container that utilizes a spring formed from an elastomer material.
It is another object of the invention to provide a lightweight, reclosable cover for a container that utilizes an elastomer spring to effect reclosing.
It is a further object of the invention to provide a lightweight, reclosable cover for a container wherein the elastomer spring may be either disposed on an outer surface or disposed adjacent an inner surface of the cover.
It is an additional object of the invention to provide a lightweight, reclosable cover for a container that utilizes an elastomer spring to provide three modes of operation of the gate: a first mode allowing the gate to close upon release of the downward pressure upon it; a second mode wherein the gate remains open when the downward pressure is released but recloses when tapped or otherwise stimulated; and a third mode where the gate remains permanently open.
It is a further object of the invention to provide a lightweight, reclosable top for a container wherein the gate occupies 90% or more of the cover area inside or outside the chuck walls.
It is a still further object of the invention to provide a lightweight, reclosable top for a container that may be formed using smaller amounts of aluminum or other material than container covers of the prior art.
It is yet another object of the invention to provide a lightweight, reclosable top for a container that may be attached to containers using existing machinery without modification.
BRIEF DESCRIPTION OF THE DRAWINGS Various objects, features, and attendant advantages of the present invention will become more fully appreciated as the same becomes better understood when considered in conjunction with the accompanying drawings, in which like reference characters designate the same or similar parts throughout the several views, and wherein:
FIG. 1A is a side elevational, cross-sectional, schematic view of a cover using an elastomer spring in accordance with the invention;
FIG. 1B is an enlarged view of a portion of the cover of FIG. 1A;
FIG. 1C is an enlarged view of another portion of the cover of FIG. 1A;
FIG. 1D is a top plan, schematic view of the cover of FIG. 1A;
FIG. 1E is a partial side perspective, cross-sectional, schematic view of the cover of FIG. 1A;
FIGS. 2A-2H are partial side elevational views of the top of FIG. 1A in various stages of initial opening and subsequent self-closing;
FIG. 3A is a side elevational, cross-sectional, schematic view of a cover using an elastomer spring disposed on an external chuck wall in accordance with the invention;
FIG. 3B is an enlarged view of a portion of the cover of FIG. 3A;
FIG. 3C is an enlarged view of another portion of the cover of FIG. 3A;
FIG. 3D is a top plan, schematic view of the cover of FIG. 3A;
FIG. 3E is a partial side perspective, cross-sectional, schematic view of the cover of FIG. 3A;
FIGS. 4A-4D are partial side elevational views of the top of FIG. 3A in various stages of initial opening and subsequent self-closing;
FIG. 5A is a side elevational, cross-sectional, schematic view of a cover using an internal elastomer spring disposed on an inner surface of the cover;
FIG. 5B is an enlarged view of a portion of the cover of FIG. 5A;
FIG. 5C is an enlarged view of another portion of the cover of FIG. 5A;
FIG. 5D is a bottom plan, schematic view of the cover of FIG. 5A;
FIG. 5E is a partial side perspective, cross-sectional, schematic view of the cover of FIG. 5A;
FIGS. 6A-6E are partial side elevational views of the top of FIG. 5A in various stages of initial opening and subsequent self-closing;
FIG. 7A is a side-elevational, schematic view of an external flush elastomer spring that may be pre-formed and cured;
FIG. 7B is a side-elevational, schematic view of the elastomer spring of FIG. 7A with adhesive applied to respective left and right adhesive-receiving walls;
FIGS. 7C-7L show a series of partial side elevational, cross-sectional, schematic views of a portion of a container cover having the elastomer spring of FIG. 7A installed with the gate at various stages of opening and re-closing;
FIG. 8A is a side elevational, cross-sectional, schematic view of another internal elastomer spring;
FIG. 8B is a side elevational, cross-sectional, schematic view of a self-closing container using elastomer spring of FIG. 8A to provide the restorative force for the reclosing;
FIGS. 8C and 8D, show detailed partial views of flange portions of the cover of FIG. 8B;
FIG. 8E is a bottom plan, schematic view of the container cover of FIG. 8B;
FIG. 8F is a bottom, perspective, schematic view of the cover of FIG. 8E;
FIG. 8G is an enlarged detail of a portion of the cover of FIG. 8F.
FIG. 8H is a partial side perspective, cross-sectional, schematic view of the cover of FIG. 8A;
FIGS. 8I-8M show a series of side elevational, cross-sectional, schematic views illustrating five sequential steps involved in opening and subsequently re-closing the container cover of FIGS. 8B-8G;
FIGS. 9A-9F show detailed side elevational, cross-sectional, schematic views of the flange region of the container cover of FIGS. 8B-8G in various stages of opening and closing, including a toggle mode;
FIG. 10A is a top plan, schematic view of a cover having a center domed external elastomer hinge;
FIG. 10B is a side elevational, cross-sectional, schematic view of the cover of FIG. 10A;
FIG. 100 is a partial side elevational, cross-sectional, schematic view a portion of the cover of FIG. 10B;
FIG. 10D is a side perspective, view of the cover of FIG. 10A;
FIG. 10E is a side elevational, cross-sectional, schematic view of the cover of FIG. 10B but with the cover crimped to side walls of a container;
FIG. 10F is a side elevational, cross-sectional, schematic view of the cover of FIG. 10A in an unopened state;
FIG. 10G is a side elevational, cross-sectional, schematic view of the cover of FIG. 10F in a partially open state;
FIG. 10H is a side elevational, cross-sectional, schematic view of the cover of FIG. 10F further open than shown in FIG. 10G;
FIG. 10I is a side elevational, cross-sectional, schematic view of the cover of FIG. 10F even further open than shown in FIG. 10H;
FIG. 10J is a side elevational, cross-sectional, schematic view of the cover of FIG. 10F with the cover automatically re-closed; and
FIG. 10K is a side elevational, cross-sectional, schematic view of the container tilted to a drinking position with the upper lip of a drinker applying inward pressure against the center domed elastomer cushion hinge.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT The present invention provides for lightweight, reclosable container tops that utilize elastomer springs to allow the cover of the container to self reclose once it has been initially opened. Elastomer springs function in manners similar to the combination flex-torsion springs that are described in detail in my previous U.S. patent application Ser. No. 14/226,898 included herein by reference.
There are many advantages in forming the necessary springs from an elastomer material and not from metal as in the prior art flex-torsion springs described and claimed in my previous work. First, elastomer springs are lighter in weight than metal combination flex-torsion springs while providing the same functionality. In addition, elastomer springs are significantly less expensive than their metallic counterparts. Also, assembly time is typically shorter compared to assembly time for covers with metallic combination flex-torsion springs. There may be a slight safety advantage if a metallic combination flex-torsion spring should fail and become disconnected from the container top.
Technically, elastomers are polymers with viscoelasticity (i.e., “elasticity”). These materials typically exhibit low values of Young's modulus as well as high failure strain compared with other materials. The term elastomer, derived from elastic polymer, is often used interchangeably with the term “rubber”. Each of the monomers which link to form the elastomers is usually made of carbon, hydrogen, oxygen and/or silicon. Elastomers are amorphous polymers existing above their glass transition temperature, so that considerable segmental motion is possible.
Elastomers or elastomer materials have several physical properties that must be evaluated to determine their suitability for use as material from which to form elastomer springs.
First is cure shrinkage percentage (%). Cure shrinkage % for these materials may range from a fraction of one percent to what the industry calls “unmeasurable.” It is absolutely essential that an elastomeric material from which springs are formed exhibits a sufficient shrinkage percentage such that an elastomer spring is able to pull a gate portion of a container cover back to the self-closed position with enough force to create a complete seal between mating flanges (i.e., fully self-closed). If the elastomer does not shrink when cured then the weight of the gate will prevent complete self-closing.
Another physical property that must be considered is adhesion strength. Container covers, especially those designed for the food and beverage industry typically are formed from aluminum having a protective coating. A good bond between the elastomer spring and the coated aluminum surface is necessary. The bond must be strong, generally far stronger than the elastomer material itself. Such a bond is similar to a welded joint in steel. A weld applied to steel is typically far stronger than the steel itself. This may be illustrated by the facts that a single edge razor blade will easily cut through an elastomer spring but will not typically be able to scrape the adhesive bond away from the surface of the coated aluminum. An etchant may be mixed with the elastomer to increase the strength of the bond.
Another mechanical property of the elastomer that must be considered in choosing an elastomer from which to form elastomer springs is percent elongation. Percent elongation is a measurement that represents how much an elastomer can be elongated or stretched before it comes to a rather abrupt stop. For example, an elastomer with a 1000% elongation specification means that particular elastomer can elongate (i.e., stretched) ten times its original cured length before the elongation process abruptly stops.
Finally, the tear strength for the elastomer must be considered. Tear strength becomes important after the elongation limit has been reached and defines the typically far greater force required to physically tear the cured elastomer than the force required to stretch the elastomer to its elongation limit.
Cure time is also important, especially if elastomer springs are to be applied to container covers in a high speed production environment.
It will be recognized that properties other than these four properties discussed above may also be important for a specific elastomer material or for a specific geometry of a particular elastomer spring.
One material found suitable for forming elastomer springs for use with self-closing container covers is Catalog Number US-SRB-201-HE fast cure silicone rubber parts binder provided by Silicone Technologies of Ogdensburg, N.Y. USA. The US-SRB-201-HE material is intended for applications demanding very high elongation (over 1000%). When cured, the elastomer resists weathering, ozone, moisture, UV and high temperatures. Further, US-SRB-201-HE works well in manual and automatic dispensing equipment.
Another material found suitable for constructing elastic polymer springs or hinges suitable for use with self-closing covers is a heat cured silicone adhesive, Catalog Number RTV-6445 provided by GE Bayer Silicones (now part of Momentive Performance Materials headquartered in Columbus, Ohio USA). RTV-6445 is a heat cured silicone elastomer having approximately a 625% elongation limit.
It will be recognized by those of skill in the polymer arts that numerous other materials exist and any suitable material may be substituted for the materials cited for purposes of disclosure. Consequently, the patent is not considered limited to the materials chosen for purposes of disclosure. Rather, the patent is intended to include any suitable elastomers from which the elastomer springs, in accordance with the invention, may be formed.
As described hereinbelow, an elastomer spring may be placed on an external surface of a cover or, alternately, the elastomer spring may be placed on or adjacent to an inner surface of the cover.
Referring first to FIG. 1A, there is shown a side elevational, cross-sectional, schematic view of a cover having an external elastomer spring in a “button top” configuration in accordance with the invention, generally at reference number C1.
Cover C1 is shown before attachment to a container represented by partial container side structure 118a, 118b. Cover C1 is shown with its gate in a sealed (i.e., unopened) state. Further, cover C1 is a simplified design used to illustrate the operation of the elastomer spring. More complex covers using other elastomer springs are described and discussed in more detail hereinbelow.
Cover C1 consists of a seaming panel 102 (best seen in FIG. 1D) surrounding a central gate or dome 108. Seaming panel portions 102a, 102b have respective distal ends 104a, 104b that are adapted for attachment to upstanding walls 118a, 118b of a container and adapted to form a peripheral seal, not shown. Note that any container or portion thereof shown or discussed herein forms no part of the present invention and is shown and/or discussed only to better describe cover C1.
In the cross-sectional view of FIG. 1A, distal ends 104a, 104b, seaming panel portions 102a, 102b, panel portions 120a, 120b, countersinks 116a, 116b, and flanges 106a, 106b are labeled for purposes of discussion. However, cover C1 is typically a circular structure best seen in FIG. 1D and distal end 104, seaming panel 102, panel 120, countersink 116, and flange 106 represented respectively thereby are continuous, circular structures, at least until the initial opening of gate 108.
Distal ends 104a, 104b of seaming panel portions 102a, 102b, respectively, form what is commonly known in the industry as a curl. Proximal ends, not specifically identified, of seaming panel portions 102a, 102b are each contiguously connected to respective panel portions 120a, 120b. Panel portions 120a, 120b terminate in respective countersinks 116a, 116b. Another panel portion 126a, 126b join respective countersinks 116a, 116b to respective tri-fold separable seams forming flanges 106a, 106b, respectively. Flanges 106a, 106b are shown in detailed portions 122a 122b in FIGS. 1B and 1C, respectively, and are discussed in more detail hereinbelow.
A gate or dome 108 occupies the central region of cover C1 surrounded by seaming panel 102 (FIG. 1D). Gate 108 in the simplified cover C1 occupies approximately 80% or more of the top surface of cover C1. It will be recognized that the novel construction may be implemented in gate or dome 108 ranging in size from substantially 100% of the cover surface down to very small sizes creating small apertures.
Chuck walls 114a, 114b define respective countersunk regions 116a, 116b.
Panel sections 126a, 126b are surrounded by countersinks 116a, 116b and fill the space between countersinks 116a, 116b and respective tri-fold flanges 106a, 106b.
An external button top elastomer spring 112 is disposed substantially atop tri-fold flange 106a and connecting panel portion 126a and gate 108. Spring 112 provides support and closure force for gate 108 after the gate has been initially opened.
Referring now also to FIGS. 1B and 1C, there are shown enlarged drawings of portions 122a, 122b of flanges 106a, 106b respectively. Of particular interest is the coined frangible seam 110a, 110b formed in flanges 106a, 106b. Frangible seam 110a, 110b defines a tear line completely around gate 108 that allows separation of gate 108 from panel 126 as gate 108 of cover C1 is “opened”. Frangible seams 110a, 110b are typically formed using a coining process. However, it will be recognized by those of skill in the art that alternate formation processes may be utilized.
Referring now also to FIGS. 1D and 1E, there are shown top plan schematic and partial side perspective schematic views, respectively of cover C1 of FIGS. 1A, 1B, and 1C. In FIGS. 1D and 1E, the relationship of each of the components and features described hereinabove with respect to FIGS. 1A, 1B, and 1C may readily be seen. The width of gate 108 is represented by arrow 128. In FIG. 1E, the relationship of external button top elastomer spring 112 to the remainder to the structure of cover C1 may readily be seen.
Referring now also to FIGS. 2A-2H, there are shown a series of side elevational, cross-sectional, schematic views of a cover having an external elastomer spring in an external “button top” configuration of FIG. 1A in various stages of opening and self-closing. Table I provides, a percentage of elongation of elastomer spring 112 and an angle of rotation of gate 108 relative to a horizontal reference line 130 connecting an upper point of frangible seam points 110a, 110b. Angle of rotation is indicated by reference number 138.
TABLE I
Figure % Elongation Angle of Gate Rotation
FIG. 2A 0.1% −5°
FIG. 2B 0.5% −10°
FIG. 2C 200% −20°
FIG. 2D 300% −30°
FIG. 2E 200% 10°
FIG. 2F 0.3% 20°
FIG. 2G 0.2% 8°
FIG. 2H 0.0% 0°
In FIG. 2A, a downward directed pressure has been exerted on gate 108 as shown by arrow 132. In response to this downward pressure, frangible seam 110a has ruptured and the remainder of flange 106a has moved downward carrying gate 108 downward into what would be an interior region of a container, not shown, to which cover C1 would be attached. Reference number 134 denotes the gap between the edges of frangible seam 110a. As may be seen by the relationship of lines 138 and reference horizontal line 130, gate 108 has rotated approximately −0.5°. This motion has caused elastomer spring 112 to be slightly elongated (approximately 0.1%). Frangible seam portion 110b has not yet ruptured.
In FIG. 2B, continued downward directed force on gate 108 has caused further downward travel of the remainder of flange 106 and gate 108. Consequently, gap 134 has widened. Gate 108 has now rotated approximately −10°. The continued downward movement has further elongated elastomer spring 112 by approximately 0.5%. Frangible seam portion 110b has still not begun to rupture.
In FIG. 2C continued downward directed force on gate 108 has caused even further downward travel of the remainder of flange 106 and gate 108. Gap 134 has now widened even further. Gate 108 has now rotated approximately −20° and elastomer spring 112 has been elongated approximately 200%. Frangible seam portion 110b has still not begun to rupture.
In FIG. 2D, frangible seam 110b has ruptured and the remaining portion of flange 106b has started to travel downward as indicated by gap 136. Gate 108 is now rotated to a 30° angle relative to reference horizontal line 130. Gap 134 has stopped widening. Elastomer spring 112 has now been elongated to its maximum extent (i.e., approximately 300%).
In FIG. 2E, the dynamics of the movement of gate 108 changes. Once frangible seam portion 110b has ruptured, elastomer spring 112 contracts and begins to pull the remaining portion of flange 106a upward thereby closing gap 134. The elongation of spring 112 shrinks to approximately 200° and the angular orientation of gate 108 shifts, moving from −30° in FIG. 2B to a 10° orientation in FIG. 2E. However, as the left edge of gate 108 rises, the right edge of gate 108 continues downward.
In FIG. 2F, frangible seam portion 110a has returned to its original, unopened position and gap 134 has shrunk to substantially zero. Gap 136 has opened as the right edge of gate 108 continues downward to create an angle of rotation of approximately 20°. The elongation of elastomer spring 112 has dropped to approximately 0.3%.
In FIG. 2G, an upward directed restoring force 140 is exerted on gate 108 by elastomer spring 112. In response to this upward directed force 140, the right edge of gate 108 has started to move upward. In FIG. 2G, the elongation of elastomer spring 112 has shrunk to approximately 0.2% and the rotation angle of gate 108 has been reduced to approximately 8°.
In FIG. 2H, cover C1 has completely reclosed and substantially resealed as both portions of the frangible seam 110a, 110b have reclosed. The elongation of elastomer spring 112 has become zero (i.e., no elongation) and the angle of rotation of gate 108 has also become zero. Line 138 has become coincident with horizontal reference line 130.
In the formation process of elastomer springs (e.g., elastomer spring 112), elastomer shrinkage during the curing process creates an important gate closing bias in the spring. This bias is sufficient to support the weight of a severed gate and hold that gate firmly in a tightly closed position. A typical shrinkage during curing is approximately 0.05%, a seemingly small amount but sufficient to provide the necessary force to hold a severed gate in a tightly closed condition. It will be recognized that elastomer raw materials having different curing shrink rates may be chosen for different spring designs and placements. Consequently, the invention is not considered limited to a particular cure shrinkage rate. Rather, the invention is intended to include any suitable cure shrinkage rate in addition to the approximately 0.05% chosen for purposes of disclosure.
It will be recognized that operation of the opening and self-reclosing of gate 108 as shown in FIGS. 2A-2H and described in the attending descriptions is controlled by the design of cover C1. The primary control over the function of gate 108 is the material choice for elastomer spring 112. In this example, an elastomer having a maximum percentage of elongation of 300% has been chosen. In FIG. 2D, the maximum elongation is reached. Consequently, no further downward travel of the left edge of gate 108 is possible and the downward directed force 132 is transferred to the right edge of gate 108 thereby causing frangible seam portion 110b to rupture. As the right edge of gate 108 is freed, elastomer spring 112 immediately begins contracting and begins pulling the left edge of gate 108 upward until the right edge of gate 108 is finally returned to approximately its unopened position and frangible seam portion 110a is closed.
If a material with a higher percentage of elongation (i.e., >300) had been chosen, the downward travel of the left edge of gate 108 could have been deeper into an interior region of the container to which cover C1 was attached. The greater downward travel could allow splashing of the container contents.
This performance is achieved by the choice of elastomer, specifically the percentage of elongation.
Referring now also to FIG. 3A, there is shown a side elevational, cross-sectional, schematic view of a cover having an external elastomer spring disposed in a chuck wall in accordance with the invention, generally at reference number C2.
Cover C2 is shown before attachment to a container, not shown, and in a sealed (i.e., unopened) state represented by partial sides 318a, 318b. Further, cover C2 is a simplified design used to illustrate the operation of the elastomer spring disposed in a chuck wall. Additional covers using other elastomer springs and spring configurations are described and discussed in more detail hereinbelow.
Cover C2 consists of a seaming panel 302 (best seen in FIG. 3D) connected to a sloping panel 320 surrounding a central gate or dome 308. Seaming panel portions 302a, 302b have respective distal ends 304a, 304b that are adapted for attachment to upstanding walls 318a, 318b of a container and adapted to form a peripheral seal, not shown. Note that any container or portion thereof shown or discussed herein forms no part of the present invention and are shown and/or discussed only to better describe cover C2. While in the cross-sectional view of FIG. 3A, seaming panel portions 302a, 302b, distal ends 304a, 304b, and panel portions 320a, 320b are labeled for purposes of discussion, cover C2 is typically a circular structure best seen in FIG. 3D and seaming panel 302, distal end 304 and panel 320 represented respectively thereby are continuous, circular structures, at least until initial opening of gate 308.
Distal ends 304a, 304b of seaming panel portions 302a, 302b, respectively form what is commonly known in the industry as a curl. Proximal ends, not specifically identified, of seaming panel portions 302a, 302b each connect to respective sloping panel portions 320a, 320b that terminate in respective tri-fold separable seams forming flanges 307a, 307b, respectively located in chuck walls or countersinks 306a, 306b. Flanges 306a, 306b are shown in detailed portions 322a 322b in FIGS. 3B and 3C, respectively, and are discussed in more detail hereinbelow.
A gate or dome 308 occupies the central region of cover C2 surrounded by tri-fold seam 316 (FIG. 3D). Dome 308 in the simplified cover C2 occupies approximately 80% or more of the top surface of cover C2. It will be recognized that the novel construction may be implemented in gate or dome 308 ranging in size from substantially 100% of the cover surface down to very small sized apertures.
An external elastomer spring 312 is disposed substantially in a chuck wall forming a portion of tri-fold flange 306a connecting panel portion 320a and gate 308. Elastomer spring 312 provides support and closure force for gate 308 after the gate has been opened.
Referring now also to FIGS. 3B and 3C, there are shown enlarged drawings of portions 322a, 322b of flanges 306a, 306b respectively. Of particular interest is the coined frangible seam 310a, 310b formed in flanges 306a, 306b. Frangible seam 310a, 310b defines a tear line completely around gate 308 that allows separation of gate 308 from panel 320 as gate 308 of cover C2 is “opened”. Frangible seams 310a, 310b are typically formed using a coining process. However, it will be recognized by those of skill in the art that alternate formation processes may be utilized.
Referring now also to FIGS. 3D and 3E, there are shown top plan schematic and partial side perspective schematic views, respectively of cover C2 of FIGS. 3A, 3B, and 3C. In FIGS. 3D and 3E, the relationship of each of the components and features described hereinabove with respect to FIGS. 3A, 3B, and 3C may readily be seen. The width of gate 308 is represented by headed line 328. In FIG. 3E, the relationship of external chuck wall elastomer spring 312 to the remainder to the structure of cover C2 may readily be seen.
Referring now also to FIGS. 4A-4D, there are shown a series of side elevational, cross-sectional, schematic views of a cover C2 having an external elastomer spring in the external chuck wall configuration of FIG. 3A in various stages of opening and self-closing. Table II provides, a percentage of elongation of elastomer spring 312 and an angle of rotation of gate 308 relative to a horizontal reference line 330 connecting an upper point of frangible seam points 310a, 310b. Angle of rotation is indicated by reference number 338.
TABLE II
Figure % Elongation Angle of Gate Rotation
FIG. 4A 0.0% 0°
FIG. 4B 150% 6°
FIG. 4C 10% 6°
FIG. 4D 0.05% 0°
FIG. 4A shows gate prior to rupturing of frangible seam 310a, 310b and before any significant elongation of elastomer spring 312. Horizontal reference line 330 is still level.
In FIG. 4B, a downward directed pressure has been exerted on gate 308 shown by arrow 332. In response to this downward pressure 332, frangible seam 310a has ruptured and the remainder of flange 306a has moved downward carrying gate 308 downward into what would be an interior region of a container, not shown, to which cover C2 would be attached. Reference number 334 denotes the gap between the edges of frangible seam 310a. As may be seen by the relationship of lines 338 and reference horizontal line 330, gate 308 has rotated approximately 6°. This motion has caused elastomer spring 312 to be slightly elongated (approximately 150.%) Frangible seam portion 310b has not yet ruptured.
In FIG. 4C continued downward directed force on gate 308 has caused even further downward travel of the remainder of flange 306 and gate 308. Gap 334 has now widened even further. Gate 308 has now rotated approximately 6° and elastomer spring 312 has been elongated approximately 10%. Frangible seam portion 310a has still not begun to rupture.
In FIG. 4D, the dynamics of the movement of gate 308 changes. Once frangible seam portion 310b has ruptured, elastomer spring 312 contracts and begins to pull the remaining portion of flange 306a upward thereby closing gap 334. The elongation of spring 312 shrinks to approximately 0.05° elongation and the angular orientation of gate 308 shifts, moving from 6° in FIG. 4C to a level (i.e. 0°) orientation in FIG. 4C. However, as the left edge of gate 308 rises, the right edge of gate 308 continues downward.
In FIG. 4D, cover C2 has completely reclosed and substantially resealed as both portions of the frangible seam 310a, 310b have reclosed. The elongation of elastomer spring 312 has become zero (i.e., no elongation) and the angle of rotation of gate 108 has also become zero. Line 338 has become coincident with horizontal reference line 330.
As stated hereinabove, in the formation process of elastomer springs (e.g., elastomer spring 112), elastomer shrinkage during the curing process creates an important gate closing bias in the spring. This bias is sufficient to support the weight of a severed gate and hold that gate firmly in a tightly closed position. A typical shrinkage during curing is approximately 0.05%, a seemingly small amount but sufficient to provide the necessary force to hold a severed gate in a tightly closed condition. It will be recognized that elastomer raw materials having different curing shrink rates may be chosen for different spring designs and placements. Consequently, the invention is not considered limited to a particular cure shrinkage rate. Rather, the invention is intended to include any suitable cure shrinkage rate in addition to the approximately 0.005% chosen for purposes of disclosure.
It be recognized that operation of the opening and self-reclosing of gate 308 as shown in FIGS. 4A-4D and described in the attending descriptions is controlled by the design of cover C1. The primary control over the function of gate 308 is the material chosen for elastomer spring 312. In this example, an elastomer having a maximum percentage of elongation of 150% has been chosen. In FIG. 4B, the maximum elongation is reached. Consequently, no further downward travel of the left edge of gate 308 is possible and the downward directed force 332 is transferred to the right edge of gate 308 thereby causing frangible seam portion 310b to rupture. As the right edge of gate 308 is freed, elastomer spring 312 immediately begins contracting and begins pulling the left edge of gate 308 upward until the right edge of gate 308 finally returns to approximately its unopened position and frangible seam portions 310a, 310b are closed.
If a material with a higher percentage of elongation (i.e., >200%) had been chosen, the downward travel of the left edge of gate 308 could have been deeper into an interior region of the container to which cover C2 was attached. The greater downward travel could have allowed splashing of the container contents.
This performance is achieved by the choice of elastomer, specifically the percentage of elongation.
Referring now also to FIG. 5A, there is shown a side elevational, cross-sectional, schematic view of a cover having an internal elastomer spring in in accordance with the invention; generally at reference C3.
Cover C3 is shown before attachment to a container, not shown, and in a sealed (i.e., unopened) state. Further, cover C3 is a simplified design used to illustrate the operation of the elastomer spring. More complex covers using other elastomer springs are described and discussed in more detail hereinbelow.
Cover C3 consists of a panel 526 (best seen in FIG. 5D) surrounding a central gate or dome 508. Panel portions 502a, 502b have respective distal ends 504a, 504b that are adapted for attachment to upstanding walls 518a, 518b of a container and adapted to form a peripheral seal, not shown between upstanding walls 518a, 518b and respective distal ends 504a, 540b of seaming panel 502a, 502b, respectively. Note that any container or portion thereof shown or discussed herein forms no part of the present invention and are shown and/or discussed only to better describe cover C3. While in the cross-sectional view of FIG. 5A, seaming panel portions 502a, 502b, distal ends 504a, 504b, and panel portions 520a, 520b are labeled for purposes of discussion, cover C3 is typically a circular structure best seen in FIG. 5D and seaming panel 502, distal end 504 and panel 520 represented respectively thereby are continuous, circular structures, at least until initial opening of gate 508.
Distal ends 504a, 504b of seaming panel portions 502a, 502b, respectively form what is commonly known in the industry as a curl. Proximal ends, not specifically identified, of seaming panel portions 502a, 502b each terminate in respective countersinks 516a, 516b. In turn, sloped panels 520a, 520b are connected to respective tri-fold separable seams forming flanges 506a, 506b. Flanges 506a, 506b are shown in detailed portions 522a, 522b in FIGS. 5B and 5C, respectively, and are discussed in more detail hereinbelow.
A gate or dome 508 occupies the central region of cover C3 surrounded by panel 526 (FIG. 5D). Dome 508 in the simplified cover C3 occupies approximately 80% or more of the top surface of cover C3. It will be recognized that the novel construction may be implemented in gate or dome 508 ranging in size from substantially 100% of the cover surface down to very small size apertures.
Panel sections 526a, 526b surrounded by countersinks 516a, 516b and fill the space between countersinks 516a, 516b and gate 508.
An elastomer spring 512 is disposed on a lower (i.e., internal) surface of panel 526a and attached both to the lower surface of panel 526a and to a lower portion of flange (i.e., the portion beyond frangible seam 510a). Spring 512 provides support and closure force for gate 508 after the gate has been opened.
Referring now also to FIGS. 5B and 5C, there are shown enlarged drawings of portions 522a, 522b of flanges 506a, 506b respectively. Of particular interest is the coined frangible seam 510a, 510b formed in flanges 506a, 506b. Frangible seam 510a, 510b defines a tear line completely around gate 508 that allows separation of gate 508 from panel 526 as gate 508 of cover C3 is “opened”. Frangible seams 510a, 510b are typically formed using a coining process. However, it will be recognized by those of skill in the art that alternate formation processes may be utilized.
Referring now also to FIGS. 5D and 5E, there are shown top plan schematic and partial side perspective schematic views, respectively of cover C3 of FIGS. 5A, 5B, and 5C. In FIGS. 5D and 5E, the relationship of each of the components and features described hereinabove with respect to FIGS. 5A, 5B, and 5C may readily be seen. The width of gate 508 is represented by arrow 528. In FIG. 5E, the relationship of internal elastomer spring 512 to the remainder of the structure of cover C3 may readily be seen.
Referring now also to FIGS. 6A-6E, there are shown a series of side elevational, cross-sectional, schematic views of the cover having an internal elastomer spring 512 of FIG. 5A in various stages of opening and self-closing. Table III provides, a percentage of elongation of internal elastomer spring 512 and an angle of rotation of gate 508 relative to a horizontal reference line 530 connecting an upper point of frangible seam points 510a, 510b. Angle of rotation is indicated by reference number 538.
TABLE III
Figure % Elongation Angle of Gate Rotation
FIG. 6A 0.0% 0°
FIG. 6B 50% −10°
FIG. 6C 20 0°
FIG. 6D 0.0% 9°
FIG. 6E 0.0% 0°
In FIG. 6A, a downward directed force pressure exerted on gate 508 as shown by arrow 532 has not yet been sufficient to rupture frangible seam 510a, 510b. Horizontal reference line 530.
In FIG. 6B, a sufficient downward directed force 532 has been exerted on gate 508 and, in response, frangible seam 510a has ruptured and the remainder of flange 506a has moved downward carrying a left edge of gate 508 downward into what would be an interior region of a container, not shown, to which cover C3 would be attached. Reference number 534 denotes the gap between the edges of frangible seam 510a. As may be seen by the relationship of lines 538 and reference horizontal line 530, Gate 508 has rotated approximately −10°. This motion has caused internal elastomer spring 512 to be slightly elongated (approximately 50%). Frangible seam portion 510b has not yet ruptured.
In FIG. 6C, continued downward directed force 532 on gate 508 has caused further downward travel of the remainder of flange 506a and gate 508. Consequently, gap 534 has widened. Frangible seam 510b has now ruptured and gate 508 is floating freely constrained only by elastomer spring 512. Gate 508 is now substantially horizontal (i.e., 0° rotation) but is now moved downward into what would be an interior of a container to which cover C3 would be attached. The continued downward movement has further elongated internal elastomer spring 512 by approximately 20%.
In FIG. 6D, frangible seam 510b has ruptured and the remaining portion of flange 506b has traveled downward as indicated by gap 538. As internal elastomer spring 512 contracts, the left end of gate 508 has risen and gap 534 has been reduced. Internal elastomer spring 512 has started to contract in FIG. 6C and is now completely contracted (i.e., at 0.0% elongation).
In FIG. 6E, cover C3 has completely reclosed and substantially resealed as both portions of the frangible seam 510a, 510b have reclosed. The elongation of internal elastomer spring 512 has become zero (i.e., no elongation) and the angle of rotation of gate 508 has also become zero. Line 538 has become coincident with horizontal reference line 530. An upward directed source provided by internal elastomer spring 512 now holds gate 508 in a tightly sealed position.
In the examples of elastomer springs 112, 312, 512, it is assumed that the springs may be formed and/or cured in situ. In a high speed can filling and sealing operation, such in situ placement and curing of any elastomer spring may be impractical.
Referring now also to FIG. 7A, there is shown a side-elevational, schematic view of an external flush elastomer spring 700 for that may be pre-extruded and cured and then machine-applied to a container cover. Spring 700 has a roughly triangular shape with a left adhesive-receiving surface 702a and a right adhesive-receiving surface 702b.
A slit 704 is disposed in the left side of spring 700 below a lower edge of left adhesive-receiving wall 702a. Slit 704 leads to an open central area 706 from an outside surface, not specifically identified, of spring 700.
A flange receiving region 708 is disposed adjacent a hook tip 724.
Referring now also to FIG. 7B, there is shown spring 700 of FIG. 7A with adhesive, shown schematically at reference numbers 710a, 710b applied to respective left and right adhesive-receiving walls 702a, 702b. Adhesive 710a, 710b may be applied to spring 700 at the time the spring is manufactured. If adhesive 710a, 710b is applied when spring 700 is manufactured, an optional protective coating, not shown, may be placed over adhesive 710a, 710b to prevent drying of the adhesive or prevent contaminating debris from clinging to the tacky surface of adhesive 710a, 710b. In alternate embodiments, adhesive, not shown, may be applied to specific areas of a container cover prior to placing spring 700 into place. This may be accomplished using a variety of materials and techniques believed to be well known to those of skill in the art.
Referring now also to FIGS. 7C-7L, there are shown a series of partial side elevational, cross-sectional, schematic views of a portion of a container cover having elastomer spring 700 installed. The depicted cover portions each show a portion of a gate 712 and a portion of a surrounding panel 714. Also shown is a tri-fold seam or flange represented by reference number 718. A frangible seam 716 is placed in gate portion 712.
As seen in FIG. 7C, elastomer spring 700 is sized and configured to fit between outer portions of gate 712 and panel 714 so that the elastomer spring's top surface, not specifically identified, is substantially flush with the gate 712 and surrounding panel 714 to which elastomer spring 700 is attached. As may readily be seen, left and right adhesive receiving surfaces 702a, 702b of a non-elongated elastomer spring 700 conform to respective surfaces, not specifically identified, of gate 712 and surrounding panel 714, respectively.
In FIG. 7D, a downward directed force 720 applied to gate 712 causes gate 712 to move downward, thereby stretching elastomer spring 700. As may be seen, central open area 706 and flange engaging region 708 are both compressed.
As seen in FIG. 7E, continued downward force 720 causes further downward travel of gate 712 with consequent further elongation of elastomer spring 700. As seen in FIG. 7E, central open area 706 and flange engaging region are both now almost completely compressed.
As seen in FIG. 7F, continued downward force 720 causes further downward travel of gate 712 with consequent further elongation of elastomer spring 700. The elongation of elastomer spring 700 allows flange engaging region 708 to slide past bottom 718 of the tri-fold flange and flange engaging region 708 is positioned for toggle mode.
As seen in FIG. 7G, as elastomer spring 700 relaxes, flange engaging region 708 is pulled upward to encircle and retain bottom 718 of the tri-fold flange. Once region 708 of elastomer spring 700 is in this position, the so-called toggle mode for the container top is set.
As seen in FIG. 7H, once region 708 of elastomer spring 700 is in the position seen in FIG. 7G, elastomer spring 700 continues to exert an upward force on the flange, represented by bottom of flange 718. Because elastomer spring 700 is not compressible, the force caused by its contraction separates frangible seam 716 and forms a gap 728. Once gap 728 is formed, the contents of the container (e.g., soda, beer, etc.) may be oscillated or swirled in the container so as to put pressure 726 on the inside of gate 712.
In FIG. 7I, gate 712 continues its upward movement and gap 728 opens further as elastomer spring 700 continues to contract to its original position as seen in FIG. 7C as the oscillated container contents continue to push against gate 112 (i.e., generates upward directed force 726).
In FIG. 7J, once flange engaging region 708 is clear of bottom of flange 718 of the tri-fold seam, elastomer spring 700 again supplies the upward directed force 722 that continues to move gate 712 upward.
And in FIG. 7K, elastomer spring 700 snaps back into its extruded shape and gap 728 closes.
Finally, in FIG. 7L, gate 712 is returned to a closed position thereby effectively re-sealing the contents of the container.
Referring now also to FIG. 8A, there is shown a side elevational, cross-sectional, schematic view of another elastomer spring, generally at reference number 800. Elastomer spring 800 is intended as an internal spring for a cover C4 having a toggle mode.
Elastomer spring 800 has a body 802 divided generally into an upper body portion 804 and a lower body portion 806. Body 802 has a hole 808 disposed therein.
An elongated tail 810 proceeded from lower body portion 806. A slot 812 separates tail 810 from upper body portion 804.
Upper body portion 804 has a flange-receiving area 814 on a right side thereof.
Elastomer spring 800 is formed such that tail 810 provides a counter clockwise (CCW) bias attempting to always exert an upward, CCW force on a lower surface of gate 826.
Referring now also to FIG. 8B, there is shown a side elevational, cross-sectional, schematic view of a self-closing container using elastomer spring 800 to provide the restorative force for the reclosing.
A gate or dome 826 is surrounded by a panel 838, shown as panel portions 838a, 838b in the cross-sectional view of FIG. 8B. As seen in FIG. 8E, panel 838 is a continuous circular structure. Intermediate gate 826 and panel 838 is a trifold seam or flange 824, also shown as seam or flange portions 824a, 824b. Flanges 824a, 824b include frangible seam 828a, 828b that separates gate 826 from panel 838.
Panel 838 is connected to countersinks 830 that are, in turn, connected to panel 832, again shown as panel portions 832a, 832b. Panel 832 is, in turn, connected to seaming panel 820, shown as seaming panel portions 820a, 820b having respective distal ends 822a, 822b.
Elastomer spring 800 is fitted against a lower surface of panel portion 838a and fastened thereto with adhesive 846 best seen in FIG. 9A. Spring tail 810 is fastened to a lower surface of gate 826 with adhesive 848, also best seen in FIG. 9A.
Referring now also to FIGS. 8C and 8D, there are shown detailed partial views of flange portions 824a, 824b respectively at reference numbers 834a, 834b.
Referring now also to FIG. 8E, there is shown a top plan, schematic view of the container cover of FIG. 8B. The relative positions of all the structures discussed in conjunction with FIGS. 8A-8B may readily be seen. In addition, the width of gate 826 is shown by arrow 840.
Referring now also to FIG. 8F, there is shown a partial side perspective view of the cover of FIGS. 8B-8E.
Referring now also to FIG. 8F, there is shown a bottom, perspective, schematic view of the cover of FIG. 8E.
Referring now also to FIG. 8G, there is shown an enlarged detail of a portion of the cover of FIG. 8F.
Referring now also to FIG. 8H there is shown a partial side perspective, cross-sectional, schematic view of the cover of FIG. 8A.
Referring now also to FIGS. 8I-8M, there are shown a series of side elevational, cross-sectional, schematic views illustrating five sequential steps involved in opening and subsequently re-closing gate 826 of the container cover.
In FIG. 8I, the cover is unopened. A horizontal reference line 842 shows that both sides of frangible seam 828 (i.e., frangible seam portions 828a, 828b) as well as both edges of gate 826 are at the same elevation or level. A downward directed force represented by arrow 844 has not yet been sufficient to rupture frangible seam 828a.
In FIG. 8J, downward directed force 844 has caused the rupture of frangible seam, at least frangible seam potion 828a. The left edge of gate 826 has dropped causing primarily the spring tail portion 810 of spring 800 to be elongated and reference line 842 has an upward slope relative to flange portion 824a.
In FIG. 8K, continued downward pressure 844 has now caused frangible seam portion 828b to rupture and gate 826, while substantially horizontal, has now been pressed downward into the container, not shown, to which the cover is attached. It should be noted that spring tail 810 is still significantly elongated.
In FIG. 8L it may be seen that once frangible seam portion 828b ruptures, spring tail 810 contracts pulling the left edge of gate 826 upward until frangible seam portion 828a is reclosed. Note that the right edge of gate 826 is still downwardly depressed and reference line 842 now has a downward slope relative to frangible seam portion 828a.
Finally, as seen in FIG. 8M, the restoring force provided by a relaxing elastomer spring 800 has caused the right edge of gate 826 to be raised to substantially its original, unopened position and frangible seam portion 828b is reclosed.
FIGS. 8G-8K have illustrated a five step “see-saw” sequence for the initial opening of the container using elastomer spring 800. Once initially opened and re-closed, the container may repeatedly be opened and reclosed. With the design of elastomeric spring 800, the container cover may be operated in a so-called toggle mode.
Referring now also to FIGS. 9A-9F, there are shown detailed side elevational, cross-sectional, schematic views of the flange region of a container top in various stages of opening and closing, including a toggle mode (FIG. 9D) wherein gate 826 is retained in a fully open state until deliberately oscillating (e.g., swirling) the container contents to force gate 826 out of the toggle mode lock.
In FIG. 9A, adhesive regions 846 and 848 may be seen adhering elastomer spring 800 to panel region 838a and gate 826. Although not clearly shown in FIG. 9A, frangible seam 820a has been previously ruptured (i.e., the container opened) and gate 826 has returned to a self-closed position as shown. The CCW bias discussed above is applied to gate 826 by spring tail 810 as indicated by arrow 850. The constant upward force provided by the CCW bias holds gate 826 in a closed position as shown.
In FIG. 9B, a downward force 844 against gate 826 causing downward movement of gate 826 with the subsequent deflection of spring tail 810. Downward pressure 844 overcomes the CCW bias built into elastomer spring 800. Bottom of flange 824a rotates toward flange receiving portion 814 of elastomer spring 800 for eventual capture and retention thereby. Additional CCW arrow 844 shows a second region of CCW rotation and/or CCW bias force development.
In FIG. 9C, continued downward pressure 844 causes additional downward movement of gate 826 and deflection of spring tail 810. Pivot point 852 around which gate 826 rotates has shifted to a point near the bottom of flange portion 828a. Flange 824a has rotated almost into flange receiving portion 814 of elastomer spring 800. Rotation of gate 826 is now around a new pivot point 854 best seen in FIG. 9E). At this point of rotation of gate 826, flange 824a is almost captured by flange receiving region 814 of elastomer spring 800.
In FIG. 9D, the rotation of gate 826 in response to continued downward pressure 844, seam receiving region 814 of elastomer spring 800 has completely captured and retained flange 824a. Spring tail 810 is maximally deflected and because of the angle of gate 826, the force on gate 826 retains flange 824a in flange receiving portion 814 of elastomer spring 800. As long as no external force is applied, gate 826 is held open.
In FIG. 9E, an internal force 860 applied against the inside surface of gate 826 forces flange portion 824a out of flange receiving region 814. Such an internal force is typically generated by oscillating (e.g., swirling, etc.) the contents of the container so as to splash or slosh the contents against the inside surface of gate 826.
In FIG. 9F, once flange 824a is released from flange receiving portion 814 of elastomer spring 800, the restoring force provided by contraction of elastomer spring 800, particularly spring tail 810, in cooperation with any continued oscillation of the container contents, brings gate 826 upward toward its initial position as shown is FIG. 9A.
Referring now also to FIG. 10A, there is shown a top plan view of a cover designated C5 having a center domed external elastomer hinge 1000 that is so-called “manufacturing center registration compliant.” The design shown in FIG. 10A allows an offset gate 1014 larger than the openings possible with center rivet designs of the prior art. In addition, the size and placement of center domed external elastomer hinge 1000 interacts well with the upper lip 1042 (FIG. 10K) of a consumer 1040 (FIG. 10L) drinking from the container, not specifically identified, to which cover C5 is attached. This process is best illustrated in FIG. 10K.
Referring now also to FIG. 10B, there is shown a side elevational, schematic view of the cover of FIG. 10A. The center domed external elastomer hinge 1000 is attached to both gate 1014 and surrounding panel 1010 by adhesive 1022, readily seen in FIG. 10B. Also visible in FIG. 10B are flanges 1012a, 1012b and frangible seam 1016a, 1016b. Reference number 1024 identifies a section of cover C5 shown in FIG. 10B.
Referring now also to FIG. 100, the area identified by reference number 1024 in FIG. 10B is shown in more detail.
Referring now also to FIG. 10D, there is shown a perspective view of cover C5.
Referring now also to FIG. 10E, there is shown the side elevational, cross-sectional, schematic view of cover C5 but attached to container sides 1026a, 1026b with a respective crimp 1028a, 1028b. Neither container sides 1026a, 1026b nor crimps 1028a, 1028b form any part of the present invention but are shown merely to show cover C5 in its intended operating environment.
Referring now also to FIGS. 10F-10J, there are shown a series of side elevational, cross-sectional, schematic views of cover C5 in various stages of being opened and subsequently self-closing after opening.
In FIG. 10F, cover C5 is shown prior to initial opening.
In FIG. 10G, in response to downwardly directed forces shown as arrow 1030, frangible seam 1016a has ruptured and the left edge of gate 1014 has moved downward. In the process of moving downward, a gap 1034 is formed. Note that frangible seam 1016b has not yet ruptured. A horizontal reference line 1032 is provided to indicate the angle of gate 1014 relative to its original, closed position.
In FIG. 10H, in response to continued downwardly directed force represented by arrow 1030, gap 1034 has possibly widened slightly and frangible seam 1016b has now ruptured creating a right gap 1036. Gate 1014 is lower than its original position (i.e., the position in FIG. 10F) and appears to be approximately parallel to horizontal reference line 1032.
With the frangible seam 1016 represented by frangible seam 1016a, 1016b, completely ruptured, the center domed external elastomer hinge 1000, previously elongated and otherwise stretched from its original shape as seen in FIGS. 10G and 10H, begins to return to its original shape. As shown in FIG. 10I, the restorative force provided by the return of hinge 1000 to its original shape exerts an upward force shown as arrow 1038 and the left side of gate 1014 is pulled upward closing gap 1034.
Finally, as seen in FIG. 10J, the right side of gate 1016 is also pulled upward to close gap 1036. The gate 1014 has now self-closed and the container is effectively resealed.
Referring now also to FIG. 10K, a partial schematic view of a face 1040 representing a consumer of the contents of the container is shown. Another useful feature of center domed external elastomer hinge 1000 is that it is placed on the cover in a location that the upper lip 1042 of consumer 1040 contacts while drinking from the container. Because frangible seam 1016 has previously been completely ruptured as described hereinabove, a gentle pressure by upper lip 1042 of consumer 1040 succeeds in pressing gate 1014 of cover C5 inward, thereby allowing liquid or other content, neither shown, through the opening 1044 in cover C5.
Since other modifications and changes varied to fit particular operating requirements and environments will be apparent to those skilled in the art, the invention is not considered limited to the example chosen for purposes of disclosure, and covers all changes and modifications which do not constitute departures from the true spirit and scope of this invention.
Having thus described the invention, what is desired to be protected by Letters Patent is presented in the subsequently appended claims.
