Patent ID: 12245710

DETAILED DESCRIPTION

FIG.1shows a perspective view of a container10, according to an embodiment of the invention. The container10may be used to hold anything such as a beverage (hot or cold), food (hot or cold), and/or other items that may or may not be consumed. The container10includes an inner wall12, an outer wall14and an enamel coating16that covers the inner wall12and the outer wall14. The container10also includes a first cavity18that is defined by the inner wall12, and a second cavity (not shown here, but shown and discussed in greater detail in conjunction withFIGS.3and4) that is defined by both the inner wall12and the outer wall14. The second cavity has had air removed from it and then sealed to prevent air from the outside ambient environment from getting back in to it. Because, the second cavity has less air for its volume than the outside ambient environment, the second cavity has a pressure that is less than the pressure in the outside ambient environment. And because the second cavity has less air for its volume, heat flows through the second cavity at a slow rate, which allows the second cavity to insulate the container's first cavity18.

By including a sealed second cavity around the container's first cavity18, and glazing an enamel coating on both the inner wall12and the outer wall14, the container10can efficiently maintain the temperature of a beverage held in the container's first cavity18while having an ornate and decorative appearance that protects the inner and outer walls12and14, respectively, and provides a fresh, clean taste that doesn't retain or transfer flavors.

Still referring toFIG.1, the container may be made of any desired material capable of being formed into the container and able to withstand the physical and thermal loads that the container will experience during use. For example, in this and other embodiments, the container10is made of a metal. More specifically, the container10is made of 304 SS (stainless steel). With this material, the configuration of the container10may be formed from a single sheet of material by stamping, forming, and/or folding, which involves bending the material; and/or the container10may be formed in segments or portions that are then welded together to form the whole container10.

The enamel coating16may be any desired enamel coating. For example, in this and other embodiments the enamel coating16is applied in one or more stages or layers and includes: 1) a matrix agent, such as silicon oxide, zirconia, and titanium oxide, 2) a flux such as sodium oxide, potassium oxide, and boron oxide, 3) an opacifier such as titanium oxide, antimony oxide, zirconia, and strontium oxide, 4) an adhesion agent such as, cobalt oxide, nickel oxide, copper oxide, antimony oxide, and molybdenum oxide, and 5) a colorant such as cobalt oxide (bright blue), copper oxide (green or red), chromium oxide (dark green); and iron oxide (ochre).

The container10may also include any other component. For example, here the container10includes a handle20that is welded to the outer wall14before the enamel coating is applied to the outer wall14, and that allows one to more easily handle the container10than one could handle a container that has such a handle omitted, like a tumbler.

Other embodiments are possible. For example, the container10may include an enamel coating that only covers the inner wall12, the outer wall14, a portion of the inner wall12, a portion of the outer wall14, or just a portion of both the inner wall12and the outer wall14.

FIG.2shows a process for making the container10shown inFIG.1, according to an embodiment of the invention. The process includes three general acts: 1) forming the first and second cavities of the container10(steps22-26), 2) applying an enamel coating16to a section of the container10(steps28-34), and then 3) increasing the insulative properties of the second cavity (steps36and38).

More specifically, the first act of the process includes forming, at step22, the first cavity18of the container10by shaping the inner wall12so that a first surface (shown inFIG.3) of the inner wall12defines the first cavity18. The formation of the first cavity18, the second cavity and the connection of the inner and outer walls12and14, respectively, are discussed in greater detail in conjunction withFIG.3. The second step24of the process' first act includes forming a second cavity of the container10by shaping the outer wall14so that a third surface (shown inFIG.3) of the outer wall14surrounds the second surface (also shown inFIG.3) of the inner wall12such that together the third and second surfaces define the second cavity. And finally, the last step26of the process' first act includes connecting the inner wall12and the outer wall14together.

After the first and second cavities of the container10are formed, the enamel coating16is applied to the container10. More specifically, the second act of the process includes forming, at step28, a hole (shown inFIG.3) through the outer wall14, to expose the second cavity to the ambient environment outside of the outer wall14. Then, the process includes applying, at step30, the enamel coating16on at least one of the following: the first surface (shown inFIG.3) of the inner wall12and the fourth surface (shown inFIG.3) of the outer wall14, while preventing the enamel coating from being deposited in the hole. After the enamel coating16is applied, the process includes heating, at step34, the container to glaze the enamel coating16and fix the coating16to the one or more surfaces (shown inFIG.3).

At step28, the hole through the outer wall14may be formed using any desired technique. For example, in this and other embodiments, the hole is stamped into and through a base (shown inFIG.3) that is then welded to the end (shown inFIG.3) of the outer wall14located at the bottom of container10. In this manner the base completes the outer wall14and encloses the second cavity except for the hole through the base. In other embodiments, the hole may simply be drilled through the outer wall14at any other location, or otherwise formed through the outer wall14.

Still referring toFIG.2, at step30, the enamel coating16may be applied using any desired technique as long as the enamel coating is prevented from being deposited in the hole of the base. For example, in this and other embodiments the enamel coating16is applied to both the first surface of the inner wall12that defines the first cavity18, and most of the outer wall14by dipping the container10into a bath of liquid enamel, and is prevented from reaching the hole by not allowing the region of the base where the hole is located to be dipped into the enamel bath. In other embodiments, the region of the base where the hole is located may be masked to prevent the liquid enamel from being deposited in the hole. In such embodiments, a region adjacent the hole is also masked to ensure that a clean metallic surface is available for a plug (shown inFIGS.3and4) that will subsequently fill the hole and seal the second cavity. In still other embodiments, the enamel may be applied to only the first surface of the inner wall12, only the fourth surface of the outer wall14, or only to a portion of each of the first and fourth surfaces. In still other embodiments, the enamel may be painted on to the container10with a paint brush. This may be desirable to provide a unique aesthetic or ornate design to the container10.

At step34, the enamel coating16is heated using any desired technique. For example, in this and other embodiments the enamel is heated to about 800° C. in a conventional oven to glaze the enamel and fix it to the first surface of the inner wall12and the second surface of the outer wall14.

By forming the hole through the outer wall14and preventing enamel from being applied to the hole, one can prevent enamel coating16from entering the second cavity. And by glazing the enamel coating16before sealing the second cavity with less pressure than the outside ambient environment, one can prevent the process for glazing the enamel coating16from damaging the sealed second cavity. Thus, one can produce a container10that includes both a sealed second cavity and an enamel glaze in the first cavity18and/or the exterior of the container10, so that the container10can efficiently maintain the temperature of the beverage held in the container's first cavity18while having an ornate and decorative appearance.

Still referring toFIG.2, after the enamel16is fixed onto the container10, the second cavity's insulative properties are enhanced. More specifically, the third act of the process includes removing, at step36, air from the second cavity. Then, at step38, while the air is removed from the second cavity, the process includes sealing the second cavity so that the pressure inside the second cavity is less than the pressure in the outside ambient environment.

Removing air from the second cavity may be accomplished using any desired technique. For example, in this and other embodiments air may be removed from the second cavity by heating the second cavity to a temperature of about 400° C. in a conventional oven. At 400° C. the air's density is substantially less than the density of air at 20° C. because the heat excites or energizes the molecules in the air. This in turn increases the pressure of the air. If the air remained trapped inside the second cavity the pressure would rise commensurate with the increase in temperature. But because the second cavity is exposed to the outside ambient environment, heated air leaves the second cavity to equalize the pressure inside the second cavity with the pressure outside in the ambient environment. After a desired amount of air leaves the second cavity, the second cavity is sealed. Then, when the remaining air in the second cavity cools back down to the temperature of the outside ambient environment, the density of the air inside the second cavity is fixed, and thus its pressure decreases to less than the pressure in the ambient environment. And because less air is trapped in the second cavity, the ability of the second cavity to resist the flow of heat through it increases.

FIG.3shows a cross-sectional view of a portion of the container10shown inFIG.1, according to an embodiment of the invention. As previously mentioned, the container10includes a second cavity46that is defined by both the inner wall12and the outer wall14, and that reduces the flow of heat into and out of the first cavity18to help insulate the first cavity18. More specifically, the inner wall12includes a first surface48that defines the first cavity18, and a second surface50. The outer wall14includes a third surface52, and a fourth surface54. As previously mentioned, the first cavity18is defined by the first surface48of the inner wall12. The second cavity46is defined by the second surface50of the inner wall12and the third surface52of the outer wall14.

The first and second cavities18and46, respectively, may be configured as desired. For example, in this and other embodiments the first cavity18is cylindrical in shape and includes an opening56that allows access to the first cavity18and that is located in a region of the inner wall12. The second cavity46surrounds the first cavity18such that the inner wall12nests within the outer wall14. And, the inner and outer walls12and14, respectively, are connected to each other at the opening56. More specifically, the inner and outer walls12and14, respectively, are formed from a single, continuous piece of material such that the outer wall14extends from the inner wall's region where the opening56is located, and then down along the inner wall12. In this manner, the second cavity46surrounds the whole first cavity18to efficiently insulate the first cavity18.

The configuration of the container10may be completed as desired. For example, in this and other embodiments a circular base60is welded to the end62of the outer wall14at an interface that is formed between two flanges. The end62of the outer wall14forms one of the flanges; and the perimeter of the base60forms the other flange. The interface where the base60is welded to the outer wall14is the region of the two flanges that contact each other when the base60is positioned to form the bottom of the container10. The hole64in the base60is located at the center of the base60, at the top of the cone66. The cone66does not have any enamel coating on it so that the plug68can make good contact with the surface of the metal. This allows plug68to form a good bond with the base60and keep the hole64filled and the second cavity46sealed.

FIG.4shows a partially exploded, cross-sectional view of the container shown inFIG.1, according to an embodiment of the invention. After the enamel coating has been fixed to the fourth surface54via heat, the hole64is sealed with the plug68during the period when air is removed from the second cavity46. The plug68seals the hole64by melting and then filling the hole64after a period of exposure to the heat during the air-removal process. The cover70is then coupled to the fourth surface54of the outer wall14to protect the plug68and cover any liquid enamel that was deposited on the base—i.e., overspray and/or over-dip. The cover70may be coupled to the fourth surface54in any desired manner. For example, in this and other embodiments the cover70is releasably held in place as shown inFIG.3by the outer wall14pinching the flange72of the cover70. In other embodiments, the cover may be releasably coupled with a conventional snap. In still other embodiments, the cover70may be fixed to the outer wall14with an adhesive or by welding the cover70to the outer wall14.

FIG.5shows a perspective view of another container80, according to another embodiment of the invention. The container80is similar to the container10shown inFIGS.1,3and4, and discussed in conjunction withFIGS.1-4, except the container80is tumbler. Tumblers typically do not have a handle like the handle20shown inFIG.1. Like these tumblers, the tumbler80also does not have a handle. Instead, one simply holds the tumbler by wrapping one's fingers around the outer wall82.

FIG.6shows another process for making the containers10and80shown inFIGS.1and5, respectively, according to another embodiment of the invention. This process is similar to the process shown inFIG.2and discussed in conjunction withFIG.2, except that after the hole64(FIGS.3and4) is formed in the outer wall14, but before the enamel coating is applied to the inner and outer walls12and14, respectively, the hole64, at step90is temporarily plugged to temporarily seal the second cavity from the outside ambient environment. This ensures that liquid enamel will not be deposited in the hole64or into the second cavity46. Then, after the enamel coating has been applied, the second cavity46, at step92, is exposed to the ambient environment.

The second cavity may be temporarily sealed using any desired technique. For example, in this and other embodiments a plug (not shown) that is elastically deformable and sized to fit into a hole64in the outer wall14is inserted into the hole64. While inserted into the hole64, the plug prevents air and, more importantly, enamel coating from flowing through the hole64and into the second cavity46. Then, after the enamel coating has been applied to the container10and/or80, the plug may be removed to expose the second cavity46in preparation for heating the enamel coating to fix the enamel coating to the container10and/or80. In other embodiments, the second cavity46may be temporarily sealed by releasably coupling a cover (not shown) to the region of the outer wall14and/or base60that includes the hole64. The cover may extend as far over the second wall14as desired to seal the hole and provide a handle that one can use to hold and manipulate the container10while applying the enamel coating16. Each of the plug and the cover can be re-used in similar processes for making additional containers10. In still other embodiments, the plug may not be releasably inserted into the hole64, and instead of withdrawing the plug before heating the enamel coating16, the second cavity46may be exposed by forming another hole through the outer wall14and/or base60.

The preceding discussion is presented to enable a person skilled in the art to make and use the invention. Various modifications to the embodiments will be readily apparent to those skilled in the art, and the generic principles herein may be applied to other embodiments and applications without departing from the spirit and scope of the present invention. Thus, the present invention is not intended to be limited to the embodiments shown, but is to be accorded the widest scope consistent with the principles and features disclosed herein.