CN109564049B

CN109564049B - Self-cooling beverage container with heat exchange unit and twist top activation system using liquid carbon dioxide

Info

Publication number: CN109564049B
Application number: CN201780049546.8A
Authority: CN
Inventors: M.西林斯
Original assignee: Joseph Company International Inc
Current assignee: Joseph Company International Inc
Priority date: 2016-06-13
Filing date: 2017-06-13
Publication date: 2021-12-03
Anticipated expiration: 2037-06-13
Also published as: JP2019519737A; EP3469275A1; CN109564049A; WO2017218494A1; US20190301784A1; JP7055755B2; BR112018075973A2; EP3469275A4

Abstract

A self-chilling container for holding food or beverage includes a Heat Exchange Unit (HEU) secured within its interior such that the food or beverage contacts an exterior surface of the HEU, the HEU being closed by a frangible membrane which is pierced by a piercing pin upon rotation of a torsional base activator in a first direction to create an imbalance such that liquid carbon dioxide contained in the HEU is converted directly from a liquid to a gaseous state and passes through a restricted orifice to the atmosphere to cool the food or beverage.

Description

Self-cooling beverage container with heat exchange unit and twist top activation system using liquid carbon dioxide

Technical Field

The present invention relates generally to containers for holding food or beverages, further comprising a heat exchange unit using liquid carbon dioxide and having an outer surface that contacts the food or beverage and changes the temperature of the food or beverage upon activation.

Background

It has long been desired to provide a simple, effective and safe device which can be housed in a container of, for example, food or beverage for changing the temperature of the food or beverage as required.

In many cases, for example where ice or refrigeration is not readily available, such as in camping, on a beach, boating, fishing, etc., it is desirable to have the beverage cool prior to drinking. In the past, ice-containing freezers and the like and containers for beverages had to be employed so that they could be cooled and subsequently applied in the desired manner. The use of such ice bins is cumbersome, takes up a lot of space and can only be maintained for a very limited time, after which the ice must be replaced. While also in use from time to time the water formed by the melted ice must be drained from the ice bin.

In view of this, there have been numerous attempts to provide a container in which food or beverages are contained and which also contains a heat exchange unit which, when activated, is capable of cooling the food or beverages contained therein. The heat exchange unit in such prior art devices contains a refrigerant material, usually under pressure, which when released absorbs heat from the surrounding food or beverage, thereby cooling it prior to consumption. The coolants utilized in prior art heat exchange units include gases under pressure such as hydrofluorocarbons, ammonia, liquid nitrogen, carbon dioxide, and liquid carbon dioxide. A system has also been developed that uses compacted carbon granules that adsorb carbon dioxide gas under pressure. Upon exposure of the heat exchange unit to the atmosphere by opening the valve, the carbon dioxide gas is desorbed and cools the food or beverage in the container. Examples of such systems are shown in us patents 7,185,511, 6,125,649 and 5,692,381. Examples of such prior art patents that include carbon dioxide in its gaseous or liquid form are shown in U.S. patents 3373581, 4688395, and 4669273. Containers utilizing such heat exchange units as shown in the prior art are complex and difficult to manufacture, thereby creating significant waste, making such prior art self-cooling beverage containers commercially unattractive. Furthermore, in the case of using liquid carbon dioxide, the release of the liquid carbon dioxide causes the liquid carbon dioxide to transform into a solid state, which provides a very limited reduction of the temperature of the food or beverage.

The applicant has found that by filling the heat exchange unit in such a vessel with liquid carbon dioxide and subsequently discharging the carbon dioxide through suitably sized flow-restricting orifices, the liquid carbon dioxide is converted directly from the liquid state to the gaseous state. Such a system is disclosed in PCT7US2015/028318, which is incorporated herein. The disclosed system utilizes machined metal components to form the flow restriction orifice. As a result, applicants have developed a system that utilizes dual function molded plastic valves to form the metering orifice, and this is disclosed in PCT/US16/23194, which is incorporated herein. The system is activated with a push button to move as a valve into position, causing the liquid carbon dioxide to change to a gaseous state and to discharge the gaseous carbon dioxide. It has been found that some users have difficulty moving the push button into position to form the restricted orifice and release gaseous carbon dioxide. In view of this, there is a need for a simple, easy to assemble and efficient self-cooling system for food or beverages, which should be easy to activate and inexpensive to manufacture.

Disclosure of Invention

In a food or beverage containing assembly, the assembly comprising: an outer container for receiving food or beverage and having a top and a bottom, the bottom defining an opening therethrough; heat Exchange Unit (HEU) comprising a metallic inner vessel having an opening and intended to be filled with liquid carbon dioxide (CO)₂) And adapted to be fixed to the outer container in the opening; a valve device secured to the HEU for providing a flow restriction orifice having a size that creates an imbalance when activated to allow liquid CO to flow₂Directly from liquid to gas, but while maintaining residual CO in the HEU₂In a liquid state until it is fully discharged, the improvement comprising a frangible member closing said opening in said HEU, said valve means comprising a penetrating pin and a rotation-activated member coupled to said penetrating pin to move said penetrating pin in contact with said frangible member to cause the frangible member to break.

Drawings

FIG. 1 is a phase diagram of carbon dioxide, showing CO₂Pressures and temperatures in the solid, liquid, gaseous, and supercritical fluid states;

FIG. 2 is a cross-sectional view of a vessel having a heat exchange unit constructed in accordance with the principles of the present invention;

FIG. 3 is a top perspective view of the container of the present invention utilizing torsional activation;

FIG. 4 is a partial cross-sectional view showing components of the activation system;

FIG. 5 is a perspective view of a heat exchange unit attachment adapter;

FIG. 6 is a cross-sectional view of the heat exchange unit attachment adapter taken at line 6-6 of FIG. 5;

FIG. 7 is a perspective view of a calibrated penetration plug of the present invention;

FIG. 8 is a side view of a calibrated penetrating plug;

FIG. 9 is a cross-sectional view of the calibrated penetrating plug taken at line 9-9 of FIG. 7;

FIG. 10 is a perspective view of a penetrating pin;

FIG. 11 is a cross-sectional view of the penetrating pin of FIG. 10 taken at line 11-11;

FIG. 12 is a perspective view of the twist base activator;

FIG. 13 is a perspective view of the ratchet attachment clamp ring;

FIG. 14 is a cross-sectional view showing the ratchet engaged with the base ring;

fig. 15 is a sectional view showing a ventilation path for carbon dioxide gas. FIG. 16 further illustrates the venting of carbon dioxide gas to the atmosphere;

FIG. 17 is a plan view of the punch-out bottom showing the bottom of the outer container;

FIG. 18 is a cross-sectional view of an alternative embodiment of a container having an HEU constructed in accordance with the principles of the present invention;

FIG. 19 is a cross-sectional view of the HEU assembly;

FIG. 20 is a cross-sectional view of the valve mechanism of FIG. 18; and

fig. 21 is a cross-sectional view of another alternative embodiment of a container having an HEU constructed in accordance with the principles of the present invention.

Detailed Description

Referring now more particularly to fig. 1, a phase diagram for carbon dioxide is shown. As shown, the carbon dioxide may have a solid, liquid, or vapor or gas phase. In accordance with the principles of the present invention, it is critical that carbon dioxide maintain its liquid phase and be prevented from entering the solid phase where dry ice may form during the use of the heat exchange unit to reduce the temperature of the food or beverage in the container. As shown, the triple point on the phase diagram is a point where three states of matter (gaseous, liquid, and solid) coexist. The critical point is a point on the phase diagram where a substance (carbon dioxide in this example) cannot be distinguished between liquid and gaseous states. The vaporization (or condensation) curve is curve 10 on the phase diagram, which represents the transition between liquid and vapor or gaseous states. As shown, the phase diagram plots pressure (typically in atmospheric pressure) versus temperature (in this case in degrees celsius). These lines represent the combination of pressure and temperature at which the two phases exist in equilibrium. In other words, these lines define the phase change point. In accordance with the principles of the present invention, the heat exchange unit is filled with carbon dioxide at a temperature and pressure such that the carbon dioxide is in its liquid state. The heat exchange unit is then sealed such that the liquid state remains in equilibrium in the heat exchange unit until such time as it is desired to allow the food or beverage in the container surrounded by the heat exchange unit to cool. At this point, an imbalance is created such that liquid carbon dioxide is allowed to transition to a vapor or gaseous state, but at the same time, it is critical that the pressure in the heat exchange unit is still maintained such that any carbon dioxide still present in the heat exchange unit remains in a liquid state. As described in more detail below, this is achieved by: providing a path for the liquid carbon dioxide to transition from its liquid state to its gaseous state and to be discharged to the atmosphere through a flow restriction orifice having a size that creates a pressure drop such that the pressure in the heat exchange unit can be maintained such that the remaining carbon dioxide contained in the heat exchange unit remains in its liquid state until such time as all of the liquid carbon dioxide transitions directly from its liquid state to its gaseous state and is discharged to the atmosphere through the flow restriction orifice, thereby completely discharging the liquid carbon dioxide in the heat exchange unit and allowing the food or beverage in the container to cool.

As mentioned above and with particular reference to the two PCT patent applications previously filed, systems have been developed which provide the desired size of the flow restriction orifice and which in fact serve to cause the liquid carbon dioxide to pass directly from its liquid state to its gaseous state and to be vented to the atmosphere and to cool the food or beverage in contact with the heat exchange unit. However, it can be determined that the mechanism developed and disclosed is fabricated from machined metal parts and in one embodiment the activation mechanism is a push button. The result is that the resulting mechanism is very expensive and difficult to manufacture commercially due to the use of machined metal parts, and in that push button activation, as noted above, it is difficult for some to depress the button sufficiently to activate the flow-restricting orifice and thereby provide the ability for the liquid carbon dioxide to transition from the liquid to the gaseous state and achieve the desired cooling. As a result, applicants have redesigned the activation mechanism and manner of creating the flow restriction orifice while eliminating expensive machined components, thereby reducing the overall cost of the device, making it commercially viable. The present invention therefore relates to a novel structure that utilizes a torsional base or rotary activator coupled to the penetrating pin to move the penetrating pin in such a way as to break the frangible member to create an imbalance to allow the liquid carbon dioxide to enter the gaseous state directly and achieve the desired cooling. This redesign is described more fully below, which implements a structure that includes a molded plastic part, and a penetrating pin as the only metal, and a heat exchange unit.

Referring now more particularly to fig. 2 and 3, the general structure of one embodiment of the present invention is shown to include a torsional base or rotary actuator 20. As shown in fig. 2, the structure includes an outer vessel 12 and a heat exchange unit 14 attached to a heat exchange unit attachment adapter 16 that is secured to a bottom 18 of the outer vessel 12. The torsional base or rotary activator 20 may be rotated in a first direction to move and break the penetrating pin towards the frangible member of the heat exchange unit. As described more fully below, a mechanism is provided to prevent rotation of the torsion base activator in the opposite direction. In a preferred embodiment, the twist base activator is allowed to rotate only in a clockwise direction, as shown by arrow 22 at the top of the twist base activator 20 in fig. 3.

As has been described previously, the top 24 of the outer container 12 is closed and includes a generally popular top or pull tab (lift tab) to provide access to the contents 26 in the outer container 12, which may be food or beverage, and in accordance with a preferred embodiment of the invention, beverage around the outer surface of the heat exchange unit 14 so that the contents 26 may be cooled to a desired drinking temperature. The exterior surface of the heat exchange element that is in contact with the beverage is coated with a food grade coating to prevent metal from entering the food or beverage, as disclosed in U.S. patent No.6,105,384, which is incorporated herein by reference.

Referring more particularly to fig. 4, the assembly of the various components of this embodiment for attaching the HEU to the outer container is shown in more detail. As shown in fig. 4, the HEU attachment adapter 16 is threadably secured to the neck portion 28 of the heat exchange unit 14. The attachment adapter 16 is made of an engineering plastic material reinforced with glass fibers. As an example, the adapter may be made of 50% glass filled polyacrylamide or glass filled polyoxymethylene or Acrylonitrile Butadiene Styrene (ABS). The specific engineering materials used must be food compatible. As shown in fig. 4, the attachment adapter has an upwardly extending neck portion that passes through an opening in the bottom 18 of the outer container 12.

With reference to fig. 5 and 6, the attachment adapter is shown in more detail. As shown therein, the adapter has a downwardly extending body portion 30 that includes threads 32 on an inner surface thereof for engaging threads on a necked-down portion of the heat exchange unit. The adapter includes an outwardly extending flange 34 that seats against the inner surface of the base 18 of the outer container 12. The adapter further includes an upwardly extending neck portion 36 which also has threads 38 formed on its outer surface and threads 40 formed on its inner surface to receive a calibrated penetrating plug as will be described more fully below. Adapter 16 also includes a pair of

posts

42 and 44 extending outwardly from neck portion 36.

Posts

42 and 44 serve to hold the HEU in place and prevent it from rotating when torsion base activator 20 is utilized, as will be described more fully below. The profile shown in figure 17 can be punched out (punch) by means of a beverage showing the way this happens, so reference should be made to figure 17. As shown therein, the bottom portion 18 of the outer container 12 has an opening 46 disposed therein for receiving the adapter 16, and a pair of

channels

48 and 50 extending from the periphery of the opening 46 are also provided. The

posts

42 and 44 fit into the

channels

48 and 50, thereby keeping the attachment adapter securely positioned in the bottom of the outer container 12. The ratchet attachment clamp ring 52 sits above the neck 36 of the attachment adapter 16. The ratchet attachment clamp ring 52 is held in place by a nut 54 that is secured to the external threads 38 of the neck portion 36 of the attachment adapter 16. Alternatively, a snap ring may be used in place of nut 54, if such is desired. The ratchet attachment clamp ring 52 will be described in more detail below. As also shown in fig. 4, the calibrated penetration plug 56 is threadably secured by threads 40 on the inner surface of the neck portion 36 of the attachment adapter 16. The penetration pin 58 is secured within the calibrated penetration plug and is utilized when the torsional base activator 20 is activated to break through the frangible heat exchange unit member 60 to create an imbalance and allow liquid carbon dioxide contained in the heat exchange unit 14 to change directly from a liquid to a gaseous state and vent to the atmosphere, as will be explained more fully below.

The twist base activator 20 is also a molded plastic member formed of fiberglass filled engineering plastic material and includes a downwardly extending activation finger 62 that engages the calibrated penetration plug 56 so as to rotate the same upon rotation of the twist base activator 20 such that the penetration plug moves downwardly and penetrates the frangible member 60 of the heat exchange unit.

Referring now more particularly to fig. 7, 8 and 9, the calibrated penetrating plug is shown in more detail. The calibrated penetrating plug 56 is also constructed using a fiberglass-filled engineering plastic material as described above. The penetration plug 56 defines a plurality of threads 64 on an outer surface of its body that engage the threads 40 on the inner surface of the neck portion 36 of the attachment adapter 16 to thereby secure the penetration plug in place. The penetration plug 56 defines a hexagonal opening 66 in its top 68 that engages the finger 62 on the twist base activator 20 to allow downward movement of the calibrated penetration plug 56, as shown in fig. 4, to complete penetration of the frangible member 60 of the heat exchange unit. The body 70 of the penetration plug defines a channel 72 that extends along the entire length of the body 70 and extends through the threads 64, as shown. The channel 72 is used to provide a passage for gaseous carbon dioxide into the area where the flow restriction ports are created to allow the gaseous carbon dioxide to pass to the atmosphere, as will be described more fully below.

The outer surface 74 of the top portion 68 of the calibrated penetration plug 56 has critical dimensions and fits in another critical area 76 of the attachment adapter, as shown in fig. 6. The combination of the outer surface 74 and the inner surface 76 provides a desired size for the flow restriction orifice, as will be described more fully below.

The penetrating pin 58 is shown in more detail in fig. 10 and 11, and reference should therefore be made to fig. 10 and 11. As shown, the penetration pin has a sharp point 78 for breaking through a frangible member of the heat exchange unit when the torsion base activator 20 is rotated in a first direction. The penetrating pin 58 has threads 80 formed on its outer surface that threadably engage threads 82 formed on the inner surface of the penetrating insert, as shown in fig. 9. While the penetrating pin is described as being threadably secured to the calibrated penetrating plug, it is understood that it may be press-fit to the calibrated penetrating plug, or formed as an overmolded unit, wherein the penetrating plug will be molded around the penetrating pin, if such is desired. As mentioned above, the penetrating pin is the only element of the assembly (other than the heat exchange unit) formed of metal. Specifically shown at 84, the pierce pin is formed with a hexagonal opening for threading the pierce pin into place in the calibrated pierce plug 56.

Referring now more particularly to fig. 12, the twist base activator 20 is shown in greater detail. Fig. 12 shows a perspective view showing the inner portion of the torsion base activator 20 cooperating with the ratchet attachment clamp ring and calibrated penetration plug 56 to move the penetration pin 58 downward to break through the frangible member 60 of the heat exchange unit. The torsional base activator 20 includes a downwardly facing outer rim 86, which will be described more fully below, for directing gaseous carbon dioxide downwardly along the outer surface of the outer vessel 12. The torque base activator 20 includes a downward facing flange 88 that seats around the outer surface of the ratchet attachment clamp ring 52. An inwardly facing wedge-shaped lip extends from the bottom of the flange 88 and defines a shoulder 89 that seats against a surface 91 on the ratchet attachment clamp ring 52, as shown in fig. 4, to hold the torsion base activator 20 in place. When the components are assembled, the torsional base activator 20 is placed in position and pushed downward. The flange 88 will move outward and the wedge-shaped lip will snap into place to secure the twist base activator 20. A plurality of stiffening ribs 90 extend between and along the top surface of outer surface 92 of flange 88 and engage the inner surface of rim 86 merely to provide additional structural integrity to twist base activator 20. The twist base activator 20 includes a downwardly extending activation finger 62 that includes an irregular surface 92 that cooperates with the opening 66 in the calibrated penetration plug to turn the calibrated penetration plug when the twist base activator 20 is rotated so that the penetration pin moves downwardly and breaks the frangible member 60 of the heat exchange unit. A plurality of ratchet teeth 94 extend completely around the actuating finger 62 and along the inner edge of the flange 88. The ratchet teeth cooperate with a ratchet attachment clamp ring, which will be described below, to allow the torsion base activator 20 to rotate only in a clockwise direction and prevent it from rotating in a counterclockwise direction. However, those skilled in the art will appreciate that the ratchet teeth and the clamp ring may be designed, for example, such that the torsion base activator is rotated in a counterclockwise direction for activation, and prevented from rotating in a clockwise direction as desired.

Referring now more particularly to fig. 13, the ratchet attachment clamp ring 52 is shown in greater detail. The ratchet attachment clamp ring 52 includes an upwardly extending flange 96 that defines a ratchet leg 98 and a ratchet leg 100 positioned 180 ° apart on the flange 96. Ratchet

legs

98 and 100 cooperate with ratchet teeth 94 to allow torsion base activator 20 to rotate only in the clockwise direction, as described above. If an attempt is made to rotate the torsion base activator 20 in a counterclockwise direction, the

ratchet legs

98 and 100 will prevent this from occurring due to the ratchet teeth 94. As shown, the ratchet attachment clamp ring includes an opening 102 that includes

recesses

104 and 106. The

recesses

104 and 106 cooperate with the

posts

42 and 44 on the attachment adapter 16 to hold the ratchet attachment clamp ring in place for proper function.

Referring now to fig. 14, the cooperation of the torque base activator 20 and the ratchet attachment clamp ring 52 is shown. As shown, the ratchet attachment clamp ring 52 is in position such that the ratchet legs (e.g., as shown at 98) cooperate with the ratchet teeth 94 such that when the torsion base activator 20 is rotated in a clockwise direction as shown by arrow 108, the ratchet legs 98 will allow this to occur. However, if an attempt is made to move the twist base activator 20 in the opposite direction, the ratchet legs 98 will engage the ratchet teeth 94 and prevent such movement.

Referring now more particularly to FIG. 15, a gaseous carbon dioxide vent path is shown when utilizing the various elements of the activation system described above. As shown in fig. 15, upon rotation of the twist base activator 20 in a clockwise direction, the finger 62 will cause the penetration plug 56 to rotate and the threads 64 thereon cooperate with the threads 40 on the attachment adapter 16 to move the penetration pin 58 downward to rupture the frangible member 60 of the heat exchange unit, creating an imbalance allowing the liquid carbon dioxide to boil and transition directly from the liquid to the vapor state. The gaseous carbon dioxide then passes upwardly as indicated by arrow 110 along channel 72 in the calibrated penetrating plug and then through flow-restricting orifice 75 formed between outer surface 74 of the calibrated penetrating plug and critical inner surface 76 of neck 38 of attachment adapter 16. The combination of these two surfaces provides the size of the flow restriction orifice and, in accordance with a presently preferred embodiment of the invention, provides a 12 micron annular opening allowing gaseous carbon dioxide to pass through the flow restriction orifice and outwardly into the region below the torsional base activator 20, as indicated by arrow 112. However, the 12 micron annular opening creates a pressure drop such that any residual carbon dioxide in the HEU remains in a liquid state.

As shown in FIG. 16, and thus with reference to this figure, once gaseous carbon dioxide has passed through the flow restriction orifice 75, it then passes through an opening 116 below the ratchet plug 98 below the rim of the flange 88 and outwardly along the bottom portion of the outer container 12 and downwardly along that surface as indicated by arrows 118. Due to this passage of gaseous carbon dioxide, cooling is not only achieved by the heat exchange unit inside the outer vessel, but additional cooling is also provided by the gaseous carbon dioxide passing along the outer surface of the outer vessel 12.

To provide cost savings for the structure described above, the heat exchange unit is fabricated from steel using a drawing and redrawing process, allowing for a high speed manufacturing process and providing a heat exchange unit with a configuration and space to receive about 90 grams of liquid carbon dioxide. In addition to this, the heat exchange unit is filled with liquid carbon dioxide, and the frangible members of the heat exchange unit are placed across the openings in the heat exchange unit and sealed prior to incorporation of the heat exchange unit into the outer container 12. This is achieved by subjecting the formed heat exchange unit to a sufficient amount of carbon dioxide pressure gas for forming liquid carbon dioxide. Once the heat exchange unit has been completely filled with 90 grams of carbon dioxide, the frangible members are placed across the opening of the heat exchange unit and sealed in place, and then the pressurized gas is vented to atmosphere and the gas-laden heat exchange unit is removed. The frangible member 60 also provides the function of a rupture disc (burst disc). If the pressure in the HEU is excessive, the member 60 will rupture and allow the carbon dioxide to safely vent to the atmosphere. By pre-bleeding (bleeding) the heat exchange unit using such a method, the overall cost is reduced by about 60%.

To provide the desired flow restriction orifice as described above, the opening is defined as H7g 6. H7 refers to the opening size 76 in the neck 38 of the attachment adapter 16 and g6 refers to the size of the outer surface 74 of the calibrated penetrating plug. The combination of these two dimensions will provide a 12 micron annular opening through which gaseous carbon dioxide must pass for eventual discharge to the atmosphere, as described above.

Referring now more particularly to fig. 18, an alternative embodiment of a beverage container is shown having a heat exchange unit that utilizes a twist top activation system, which is a simplified version as described above. As shown in fig. 18, the beverage container 120 has a heat exchange unit 122 secured to a bottom 124 of the container 120. The support collar 126 is positioned on the neck 128 of the HEU with one end seated against the HEU and the other end seated against the bottom of the container, and the attachment housing 130 is threadably secured to the neck 128 of the HEU 122 and thus secures the HEU to the bottom 124 of the outer container 120.

The assembly of the HEU is shown in more detail in fig. 19, and reference is therefore made thereto. As shown, the HEU 122 includes threads 132 on its outer surface and additional threads 134 on its interior. An adapter 136 is threadably secured to the threads 134 on the interior of the neck of the HEU 122. The adapter 136 is hollow as shown and defines a shoulder 138 that receives a spring 140. The valve stem 142 is inserted into the hollow interior of the adapter 136. The valve stem 142 defines an inwardly directed lip 144 at its lower end. The lip 144 snaps into place and seats in a groove 146 defined in a frangible member or rupture disc holder 148. A frangible member or rupture disc 150 is a frangible member and is seated in the holder 148 and held in place by a grub screw 152. A Polytetrafluoroethylene (PTFE) gasket 154 is seated on top of rupture disc holder 148 and against the bottom of adapter 136 to provide a seal to retain liquid carbon dioxide contained within HEU 122, as will be described more fully below. The headless screw 152 defines an opening 156 therein. Those skilled in the art will appreciate that rupture disk 150 is continuously exposed to the pressure of the liquid carbon dioxide contained in HEU 122, and if the pressure therein exceeds a predetermined amount, rupture disk 150 will rupture and the liquid carbon dioxide will then begin to boil and be expelled through opening 156 and outwardly into the atmosphere. Opening 156 serves to throttle the gas to some extent to protect the components contained in the valve mechanism upstream of rupture disk 150.

To fill the HEU 122 with liquid carbon dioxide, the assembled HEU shown in fig. 19 is contacted by a liquid carbon dioxide fill head that pushes the valve stem 142 downward as shown in fig. 19, causing the rupture disc retainer 148 to move downward, breaking the seal defined by the PTFE gasket 154 so that liquid carbon dioxide can subsequently enter the HEU 122. When the desired amount of liquid carbon dioxide is contained in the HEU 122, the fill head is removed and the spring 140 moves the valve stem upward, allowing the seal defined by the gasket 154 to engage between the top of the rupture disc holder 148 and the bottom of the adapter 146 to again provide a seal and maintain the seal so that the liquid carbon dioxide remains in equilibrium in the HEU 122. Once this is achieved, the filled HEU will then be assembled with the rest of the valve mechanism, as shown in fig. 18.

The details of the valve mechanism are shown in more detail by referring more specifically to fig. 20. As shown in fig. 20, the penetration pin 160 is contained in the penetration plug 162 as described above. The penetrating pin 160 is metallic and has a sharp point 164. The penetration plug 162 defines a plurality of drive splines therein which are engaged by downwardly facing fingers 164 on a torsional activator 166. The penetration plug 162 is carried by the attachment housing 168 in a manner that is carried along the torsion activator 166Upon rotation in one direction (e.g., clockwise as described above), penetration plug 162 drives penetration pin 160 downward such that point 164 contacts and punctures rupture disk 150, allowing liquid carbon dioxide contained in HEU 122 to disproportionate, boil and transition directly from the liquid state to the gaseous state, and move upward through the opening around the penetration pin in stem 142 and outward through channels 72 (fig. 8) formed in the threads of penetration plug 162 to engage the lower surface of torsional activator 166 and pass outward and downward as described above. A restrictive orifice is disposed in the gas flow path as described above and sized to provide a pressure drop to divert remaining CO in the HEU₂Remains in the liquid state until all of it is directly converted to the gaseous state and vented as described above. As can be seen from the display of fig. 20, the structure of the valve mechanism included in this embodiment is simplified relative to the embodiment described above, thereby allowing for easier assembly and providing a cheaper valve mechanism. For example, the attachment housing 168 is a single molded plastic component, replacing the attachment adapter 16, ratchet attachment clamp ring 52, and nut 54 of the embodiment shown in fig. 4.

The support ring 126 carries O-

rings

170 and 172. The O-ring 170 prevents the beverage contained in the outer container 120 from contacting the outer surface of the HEU, which does not have a protective coating thereon. The O-ring 172 provides a seal to prevent the beverage contained in the outer container 120 from exiting the interior of the container 120.

With reference to fig. 21, there is shown a further embodiment of a twist activated HEU constructed in accordance with the principles of the present invention. The configuration shown in fig. 21 has a different adapter 174 designed to accommodate a different type of HEU than that shown in fig. 20. As also shown in fig. 21, the HEU support loops 176 are slightly different in structure from those shown in fig. 20. In all other respects, the structure shown in fig. 21 is the same as and functions in the same manner as that shown in fig. 20, and thus the description of fig. 20 is incorporated herein with respect to fig. 21.

There is thus described herein a modification of a heat exchange unit that has been designed to be activated by a twisting action (as opposed to using a push button type activation as previously described) and to use a molded plastic part (as opposed to a machined metal part as previously described) to significantly reduce the manufacturing cost of the system.

Claims

1. An improvement in a self-cooling food or beverage container (12) having a heat exchange unit (14) secured to an opening in a bottom thereof and extending into contact with the food or beverage and having a valve mechanism (140) 142 for passing liquid carbon dioxide into the heat exchange unit through the opening therein, the improvement characterized in that

A frangible member (60-150) closing an opening in the heat exchange unit;

the valve mechanism includes a penetrating pin system (56, 58-160, 162) disposed adjacent the frangible member;

a rotary activation member (20-166) coupled to said penetrating pin system adapted to rotate in only one direction, upon such rotation, advancing said penetrating pin to engage said frangible member to penetrate it to allow liquid carbon dioxide to transition from a liquid state to a gaseous state and discharge along a flow path; and

a flow restriction orifice (75) disposed in the flow path and sized to create a pressure drop that maintains any remaining carbon dioxide in the heat exchange unit in a liquid state.

2. The improvement of the self-cooling food or beverage container as defined in claim 1 wherein the penetrating pin system includes a penetrating pin (56-162) and a penetrating pin (58-160) carried by said penetrating pin, and said rotary activation member (70-166) engages said penetrating pin to rotate said penetrating pin to advance said penetrating pin into engagement with said frangible member.

3. The improvement of the self-chilling food or beverage container as defined in claim 2 wherein said penetration plug defines an opening (66) therein and said rotary activation member includes a finger (62) extending into said opening in said penetration plug to allow rotation of said penetration plug.

4. The improvement of the self-cooling food or beverage container as claimed in claim 3, wherein the outer surface (74) of the penetrating spigot cooperates with a region (76) of the attachment adapter (16) defining said flow restriction orifice (75).

5. The improvement of the self-cooling food or beverage container as defined in claim 1 wherein said frangible member acts as a rupture disc always associated with liquid CO₂Contact and rupture when the pressure in the HEU reaches a predetermined level.

6. The improvement of the self-cooling food or beverage container as claimed in claim 1 wherein said rotary activation member includes ratchet teeth (94) cooperating with ratchet legs (98-100) to prevent rotation of said rotary activation member in a direction other than said one direction.

7. The improvement of a self-cooling food or beverage container as claimed in claim 1 in which said rotary activation means includes a downwardly directed outer rim (86) which directs the exiting CO₂The gas flows down along the outer surface of the container (12).

8. The improvement of the self-cooling food or beverage container as defined in claim 1 wherein said heat exchange unit includes a neck portion (28-128) having threads (132) on its outer surface and further including an adapter (16-136) threadably secured to said threads on the neck of the HEU to secure the HEU to the bottom of the container.

9. The improvement of the self-cooling food or beverage container as claimed in claim 8, wherein the adapter is made of an engineering plastic material comprising glass fiber filled polyacrylamide (GRP) or Polyoxymethylene (POM) or Acrylonitrile Butadiene Styrene (ABS) with glass fiber.

10. The improvement of the self-cooling food or beverage container as claimed in claim 8 wherein said rotary activation member (20-166) includes a downwardly facing flange (88) having an inwardly facing wedge lip which secures the rotary activation member to the adapter.

11. The improvement to the self-cooling food or beverage container as claimed in claim 8 further including a frangible member retainer and a headless screw (152) which secures the frangible member in place in the retainer.

12. The improvement of the self-cooling food or beverage container as defined in claim 8 further including a sealing member seated between the frangible member retainer and the bottom of the adapter (136) to maintain liquid carbon dioxide in the HEU in equilibrium.

13. The improvement from a self-cooling food or beverage container as claimed in claim 12 wherein the adapter is hollow and further including a valve stem (142) disposed within the hollow interior of the adapter and a spring urging the valve stem to a position to urge the frangible member to the sealing position, the valve stem being movable against the force of the spring to move the frangible member retainer away from the bottom of the adapter to allow liquid carbon dioxide to enter the HEU.

14. The improvement from a cold food or beverage container as claimed in claim 11 wherein said headless screw includes an opening through which pressure in the HEU is communicated to the frangible member, the opening in the headless screw being sized to regulate the pressure of the gaseous carbon dioxide being released in the event that the frangible member ruptures due to increased pressure in the HEU.

15. The improvement of the self-cooling food or beverage container as claimed in claim 8 further comprising an HEU support ring (126) surrounding a neck portion (128) of the HEU and seated against the HEU at one end thereof and against the bottom of the container at the other end thereof for securing the HEU to the container.