Patent Publication Number: US-6981387-B1

Title: Apparatus for delivering carbonated liquid at a temperature near or below the freezing point of water

Description:
CROSS REFERENCE TO RELATED APPLICATIONS 
   Provisional Patent Application No. 60/428,333 filed Nov. 22, 2002. 

   I. BACKGROUND OF THE INVENTION 
   1. Field of Invention 
   A double tank system and refrigerated compressor device for mixing water and carbon dioxide to produce a carbonated liquid within an inner tank, cooled by compressor coils attached to the inner tank, placed within the outer tank, with a vacuum or a highly insulated foam placed in a void between the inner tank and the outer tank, delivering the chilled carbonated water product to a faucet bank for mixing with a cooled beverage syrup, providing the carbonated beverage at a temperature at or below the freezing point of water, due to the enhanced cooling ability of the system and device. 
   2. Description of Prior Art 
   The following United States patents were discovered and are disclosed within this application for utility patent. All relate to a type of beverage dispenser having a compressor which delivers a produce at a reduced temperature or in a frozen state. 
   In U.S. Pat. No. 6,276,150 to Nelson, a beverage is mixed with carbon dioxide and then through a chiller, then further delivered to the primary target of the invention, which is the faucet or dispenser, allowing ice into the cup, followed by the cooled beverage through the same faucet means. It contains no double tank system nor claim of delivering a liquid at or below 32 degrees F. A frozen beverage, which has entered a state of crushed ice is the delivery subject of the dispenser in U.S. Pat. No. 6,301,918 to Quartarone, which also utilizes an auger to lift the frozen product into an expulsion tube to deliver the frozen product to an outlet. 
   A single tank carbonator is disclosed in the beverage dispenser of U.S. Pat. No. 5,140,832 to Deininger, which is the common state of the prior art. U.S. Pat. Nos. 4,866,949 and 4,970,871 to Ridick demonstrate refrigerators with single tank carbonators incorporated within the refrigerator. 
   The present apparatus discloses an inner tank within an outer tank, with the refrigerant coils positioned on the outer surface of the inner tank, the inner tank and outer tank also being sealed within each other with a vacuum between the two tanks or some other insulation material, a pre-chiller or heat exchanger, and also incorporates syrup tubes within the inner tank for the pre-cooling of the syrup before being mixed with the carbonated liquid at the delivery faucet. 
   II. SUMMARY OF THE INVENTION 
   The current state of the beverage dispenser industry provides several mechanisms to provide a carbonated beverage to a customer by mixing water, carbon dioxide gas and a flavored syrup in a cooled environment with the mixed beverage delivered to one or more faucets on a counter top drink dispenser. The temperature of the dispensed beverage varies to a great extent, but no current machine is able to deliver the beverage to the faucet at or below freezing, the temperature of the beverage at the faucet being somewhere around 40 degrees. In addition, only so much liquid may be chilled by the current machines before the liquid being dispensed starts being delivered at even higher temperatures, exceeding the cooling capacity of the machines. Also significant in effecting these current machines in the environmental temperature surrounding the machines, outdoor dispensers being a greater challenge to regulate than indoor dispensers. 
   The present apparatus delivers the mixed soft drink beverage to the faucet at or below the freezing temperature of water which provides several benefits over the prior art. First, an advantage is gained by the beverage being less likely to melt the ice in a beverage glass upon dispensing the beverage, slowing the process of the ice turning to water which would dilute the beverage once dispensed. A second advantage is gained by the apparatus allowing for a greater volume of beverage being able to be dispensed at a lower temperature than the prior art devices because the inner tank of the double tank carbonator is not exposed to the environment surrounding the prior art carbonators, being insulated from the environment by either the vacuum in the void between the inner tank and outer tank or a highly insulating foam product. A third advantage lies in the cooling coils being contained within the same void as the inner tank, making the cooling coils transfer their cooling properties more efficiently to the inner tank and its contents than if the cooling coils were exposed to the environment of the prior art devices. This allows the refrigerant circulating system to run less often than the prior are systems, saving costs for energy required to operate the refrigerant circulating systems, which is the bulk of the cost of operation of these type of beverage dispensing units. 
   Noted in the apparatus is a distinction between diet syrup lines and sugared syrup lines. This is due to the effect of temperature on these ingredients. Sugared syrups may be chilled below the freezing point of water without effect on the diet syrup, to some extent, provided that the sugared syrup is not frozen. However, with diet syrup, especially when flavored with the current artificial sweetener ingredients, these sweeteners are broken down when chilled too close to the freezing point of water, and can alter the flavorings to the point of making these artificial sweeteners become bitter. Therefore, the diet syrup lines are channeled through a heat exchange unit, cooled by fresh water, prior to delivery to the faucet bank, while the sugared syrup lines are optionally channeled through syrup coils traversing the inner tanks, lowering the sugared syrup to a temperature similar to the carbonated water. 
   The primary objective of the apparatus is to provide a beverage dispensing apparatus which delivers a carbonated beverage to its faucets at or below the freezing point of water by providing the apparatus with an inner tank within an outer tank with cooling coils between the two tanks in an environment not affected by outside factors including heat, air pressure or adverse weather conditions. 
   A secondary objective of the apparatus is to provide a more economically efficient method and space convenient component arrangement for pre-cooling the components being mixed into a carbonated beverage prior to their being combined and delivered to the faucet to enhance the efficiency of the beverage dispenser for lower the cost of operation. A third objective would be to provide the apparatus in a counter top embodiment for restaurant and concession use which is less effected by the surrounding environment of the location of the apparatus. 

   
     III. DESCRIPTION OF THE DRAWINGS 
     The following drawings are submitted with this utility patent application. 
       FIG. 1  is a flow diagram of the apparatus for delivering carbonated liquid at a temperature near or below the freezing point of water showing the integrated system. 
       FIG. 2  is a flow diagram of the water circulation system. 
       FIG. 3  is a flow diagram of the refrigerant system. 
       FIG. 4  is a cutaway side view of the inner and outer tank, the hub and the temperature probe and sleeve. 
       FIG. 5  is a side view of the inner tank within a cutaway side view of the outer tank. 
       FIG. 6  is a front view of the heat exchange unit. 
       FIG. 7   a  is a side view of a syrup tube. 
       FIG. 7   b  is a side cross section of the syrup tube. 
       FIG. 8  is a top view of the heat exchange unit. 
       FIG. 9  is a cross section of the outer syrup coil tube. 
       FIG. 10  is a perspective view of the hub. 
       FIG. 11  is a top view of the outer tank indicating the placement of the plurality of syrup coils. 
       FIG. 12  is a side view of the outer tank indicating the placement of the plurality of syrup tubes within the inner tank. 
       FIG. 13  is an exploded view of the fluid level probe, the hub and sleeve assembly. 
   

   IV. DESCRIPTION OF THE PREFERRED EMBODIMENT 
   An apparatus for delivering a carbonated beverage at or near the freezing point of water, connected to a fresh water line, a carbon dioxide gas tank and a beverage syrup container which blends the fresh water, carbon dioxide gas and beverage syrup together for dispensing a cold soft drink is shown in  FIGS. 1–13  of the drawings and comprises essentially a double tank carbonator  10 ,  FIGS. 1–5 , having an inner tank  20  and an outer tank  30 , with an insulated void  14  between said inner tank  20  and outer tank  30 , the inner tank  20  surrounded by a set of refrigerated cooling coils  50  integrated with a refrigerant circulating system  100 ,  FIG. 3 , a carbon dioxide cylinder  300  with compressed gas lines  302  directing carbon dioxide gas to the inner tank  20  and to a plurality of syrup pumps  185 , a plurality of syrup lines  186 ,  188  connected to a plurality of syrup tanks  180 ,  182 , including diet drink syrup tanks  180  and sugared syrup tanks  182 , each syrup line  186 ,  188  connected to a separate syrup pump  185 , a first fresh water line  202  providing fresh water to a heat exchange unit  70 ,  FIGS. 6 and 8 , and a second fresh water line  203  from the heat exchange unit  70  to a water circulating loop  210  in a water circulating system  200 ,  FIG. 2 , a fluid level probe  65  within the inner tank  20  regulating fresh water being delivered to the inner tank  20 , and a temperature sensing means  60  within the inner tank  20  regulating the refrigerant circulating system  100 . The fresh water and carbon dioxide are combined within the water circulating loop  210  to form soda water which is then directed through a pump  214  to the inner tank  20  to a soda water inlet line  205  where the soda water is chilled to a temperature at or below the freezing temperature of water, after which the soda water is delivered to the faucet bank  350 , cycled through the heat exchange unit  350  and then returned to the water circulating loop  210 , the diet syrup lines  186  running through the heat exchange unit  70  directly to the faucet bank  350  and the sugared syrup lines  188  connected to one of a plurality of syrup coils  80 ,  FIGS. 7A ,  7 B,  9 ,  11  and  12 , passing within the inner tank  20  of the double tank carbonator  10 , further directed to the faucet bank  350 , the faucet bank  350  blending the soda water with diet syrup for diet beverages, blending the soda water with sugared syrup for sugared beverages, a fourth fresh water line  209  dispensing fresh water at the faucet bank  350 , for consumption or further mixing with tea or other non-carbonated beverages. 
   As further defined, the water circulating system  200 , shown in  FIG. 2 , further comprises the first fresh water line  202  connected to the heat exchange unit  70 , then to a second fresh water line  203  to the water circulating loop  210 , the water circulating loop  210  having a check valve  212 , a solenoid  213  and a water circulating pump  214 , shown in  FIG. 2  of the drawings. A third fresh water line  204  delivers fresh water to the water circulating loop  210 , through the pump  214  to a soda water inlet line  205 , then to a water inlet tube  220  within the inner tank  20  of the double tank carbonator  10  where fresh water and return soda water are further mixed with carbon dioxide to form the soda water chilled to a temperature at or below the freezing temperature of water and then directed through a soda water outlet line  206  to the faucet bank  350 . From the faucet bank  350 , a first return soda line  207  delivers the chilled soda water to a central soda water tube  78  in the heat exchange unit  70  to a second return soda line  208  which connects to the third fresh water line  204 , the soda water prevented from entry into the third fresh water line  204  by the check valve  212 . This water circulating system keeps the fresh water and soda water under pressure from the carbon dioxide gas circulating within the system so the liquids do not freeze within the system, such liquids being near or below their normal freezing points. 
   As the carbonated liquid in mixed within the inner tank  20  and the temperature reaches the freezing point of water, an ice bank will be formed within the inner tank  20 . The temperature sensing means  60 , again indicated in  FIG. 2  of the drawings, should be housed within a sealed channel  62  penetrating through the outer tank  30  and the inner tank  20  terminating near where the ice bank would be formed. The temperature sensing means  60  is integrated with the refrigerant circulating system  100 , deactivating the refrigerant circulating system  100  by sensing the temperature of the carbonated water within the inner tank as it reaches a determined set point. 
   The refrigerant circulating system  100  is further defined in  FIG. 3 , as having the set of refrigerated cooling coils  50  attached to the inner tank  20  within the void  14  between the inner tank  20  and the outer tank  30 , the void being filled with either a vacuum or a highly insulating expansion foam completely filling the void  30 . The refrigerated cooling coils  50  are connected to a first refrigerant line  102 , passing over an accumulator  110 , through a dryer  120  to a compressor  130 , to a second refrigerant line  104  directed to a condenser unit  140 , to a third refrigerant line  106  traveling back over the accumulator  110  to the refrigerated cooling coils  50 . The refrigerant circulating system  100  is filled with a compressed refrigerated gas which under compression, is delivered at a temperature below the freezing point of water. The refrigerant circulating system  100  is regulated by the temperature sensing means  60 . 
   The double tank carbonator  10  is further defined in  FIGS. 4 and 5 , including the outer tank  30  containing the inner tank  20 , a lower end  24  of the inner tank  20  suspended within a lower end  34  of the outer tank  30  by a support peg  12 . The void  14  is located between the inner tank  20  and the outer tank  30 , and as previously indicated, the void  14  is either drawn to a vacuum or is filled with the highly insulating expansion foam, with a seal cap  16 , indicated in  FIG. 5  of the drawings, giving access to the void  14  during the time of manufacture of the double tank carbonator  10 . A hub  40 , shown in  FIGS. 4–5 ,  10  and  13 , is attached to an upper end  32  of the outer tank, penetrating into an upper end  22  of the inner tank  20 , the hub  40  having a central opening  44  attaching to a perforated inner cylinder  46  within which is inserted the fluid level probe  65 , attached to the hub  40  by an attaching means  48 , the fluid level probe  65  regulating the flow of fresh water into the inner tank  20 . This fluid level probe  65  may be mechanical float mechanism or as an electronic bridge type probe, depicted in  FIG. 13 . The fluid level probe  65  is connected to the solenoid  213 , which regulates the flow of fresh water into the water circulating loop  210 , the fluid level probe  65  signaling the solenoid  213  to open to allow fresh water into the water circulating loop  210  when water in the inner tank  20  is low, and signaling the solenoid  213  to close to disallow fresh water into the water circulating loop  210  when the inner tank  20  is full. 
   The hub  40  has a plurality of holes  42 , a first hole  42   a  accepting the compressed gas line  302  from the carbon dioxide cylinder  300  introducing carbon dioxide gas into the inner tank  20 , a second hole  42   b  accepting the soda water inlet line  205  connected to the water inlet tube  220  forming a J-tube  222  within the inner tank  20 , a third hole  42   c  accepting the soda water outlet line  206 , and a fourth hole  42   d  provided for pressure relief. The J-tube  222 , the compressed gas line  302  and the soda water outlet line  206  are directed to the lower end  24  of the inner tank  20 . In the alternative, any of the lines running through the hub  40  may be introduced by direct line to the inner tank without passing through the hub, by penetration of the outer tank and inner tank. 
   The heat exchange unit  70 , shown in  FIGS. 6 and 8 , further comprises a sealed cylindrical frame member  72  having an inner cavity  73  with a fresh water inlet  74  and a fresh water outlet  75 , the fresh water inlet  74  connected to the first fresh water line  202  and the fresh water outlet  75  connected to the water circulating loop  210  through the second fresh water line  203 . Within the heat exchange unit  70  are a plurality of diet syrup tubes  76  through which the diet syrup passes, the diet syrup tubes  76  connecting to the diet syrup lines  186 , cooling the diet syrup within the diet syrup lines  186  prior to terminating at the faucet bank  350 . The heat exchange unit  70  may be attached to the outer tank  30  of the double tank carbonator  10  by a bracket  77 , shown in  FIG. 8  of the drawings. A central soda line  78  also runs within the inner cavity  73 , connected between the first return soda line  207  and the second soda return line  208  providing the heat exchange unit with the capacity to lower the temperature of the fresh water flowing through the inner cavity  73  and the diet syrup within the diet syrup tubes  76 . 
   Each of the syrup coils  80 , shown in  FIGS. 7A ,  7 B and  9  of the drawings, is a closed tube having a syrup inlet  81  connected to a sugared syrup line  188  introducing the sugared syrup into the syrup coil  80  which further has an outer syrup tube  82  with an interior surface  83  aligned with a multiplicity of inwardly protruding dimples  84  to create a turbulence within the syrup coil  80 . A syrup outlet  86 , connected to an internal outlet tube  87  is located within the outer syrup tube  82  to extract the sugared syrup from within the outer syrup tube  82 . This syrup outlet  86  is connected to the faucet bank  350 . Each syrup coil  80  may be secured within the double tank carbonator  10  as indicated in  FIGS. 11–12  of the drawings. 
   Most preferably the double tank carbonator  10  is made entirely of stainless steel, which is demonstrated to have the desired thermal qualities sought in the apparatus. The cooling coils  50  are preferably copper which is attached by soldering the formed copper to the inner tank  20 . The hub  40  is best presented as a stainless steel hub with the plurality of holes  42  machined through the hub  40  leading into the inner tank  20 . The heat exchange unit  70  would preferably be made of stainless steel or another metal which would not be subject to corrosion and would have the thermal qualities required to operated the apparatus efficiently. The syrup coils  80  would also be made of similar metal materials with the interior surface  83  of the syrup coils  80  having a smooth surface or inner lining that would be resistant to a buildup of syrup over time. 
   The water lines and syrup lines within the apparatus would be best suited if made from stainless steel or copper with like metal couplings, although the current art uses flexible plastic hoses to connect most syrup containers and carbon dioxide cylinders to soft drink dispensers. Flexible plastic hoses would be sufficient for the lines connecting the external carbon dioxide cylinder and the external syrup containers to the apparatus, but likely not sufficient to be use for connecting the inner components of the apparatus. 
   It is also preferred that the inner tank  20  and outer tank  30  be a cylindrical shape with the upper end  22  and lower end  24  of the inner tank  20  and the upper end  32  and the lower end  34  of the outer tank  30  being domed, which is preferred in the art for stability of the tanks under the pressure of a vacuum or under the pressure of a highly insulating expansion foam filling the void  14  between the inner tank  20  and outer tank  30 . 
   In addition to its implementation into the apparatus, the double tank carbonator  10  may by itself be incorporated into current art soft drink dispensing devices and is therefore independently made part of the specification. This independent embodiment of the double tank carbonator  10  comprises the inner tank  20  suspended with the outer tank  30 , the void  14  between the inner tank and outer tank again being occupied by a vacuum or highly insulating expansion foam, with the double tank carbonator  10  having the hub  40  accepting the third fresh water line  204  and the compressed gas line  302  from the carbon dioxide cylinder  300 , and having a soda water outlet line  206  connecting to a faucet bank  350 . Syrup coils  80  may be integrated within the double tank carbonator  10  with a syrup inlet  81  connecting to the syrup lines  186 ,  188  and a syrup outlet  86  connecting the syrup coil  80  to the faucet bank  350 . The cooling coils  50  located with the void  14  may be connected to an outside refrigerant circulating system  100  with the temperature sensing means  60 , housed within a sealed channel  62  penetrating through the outer tank  30  and inner tank  20 , controlling the refrigerant circulating system  100 . The fluid level probe  65 , contained within the perforated inner cylinder  46 , inserted through the central opening  44  of the hub  40 , may be integrated with any fresh water line to control the flow of fresh water into the inner tank  20 . 
   While the invention has been particularly shown and described with reference to a preferred embodiment thereof, it will be understood by those skilled in the art that changes in form and detail may be made therein without departing from the spirit and scope of the invention.