Patent Publication Number: US-2007114681-A1

Title: Method and apparatus for an oval carbonator

Description:
BACKGROUND OF THE INVENTION  
      1. Field of the Invention  
      The present invention relates to beverage dispensing and, more particularly, but not by way of limitation, to methods and apparatus for beverage dispensing with cold carbonation.  
      2. Description of the Related Art  
      In the post-mix beverage dispensing industry, carbonated beverages account for the largest segment of the different beverage types. Unfortunately, carbonation of a beverage can dramatically affect the quality of a finished drink. Proper carbonation must be achieved in order to consistently produce quality drinks, including minimal foaming.  
      Over the past decades, it has been determined that colder temperatures in the carbonation process produce better carbonation efficiencies and can be accomplished at lower carbon dioxide pressures. As such, the carbonation methods used to carbonate finished drinks have moved from ambient carbonators to various forms of chilled carbonators. A further deviation from this trend includes using prechilled water in carbonators to further reduce the temperatures in the carbonation process.  
      Current trends include casting the carbonators directly into a cold plate of a beverage dispenser. Cast-in-place carbonators operate at-reduced temperatures due to the decreased temperature of the cold plate, thereby increasing absorption of the gas in the carbonator.  
      While cast-in-place carbonators provide increased efficiencies, it is often a struggle to maximize the size of the carbonator, without increasing the size of the cold plate. Further complications arise when the multitude of preformed dispensing tubes located in the cold plate must be adjusted to provide clearance for the integral carbonator. Attempts have been made to reduce the height of the carbonator, but have resulted in complex designs that are difficult to manufacture.  
      Accordingly, an improved cast-in-place carbonator design that would increase carbonator efficiencies, provide for simplified dispense tubing designs, and a decreased cold plate thickness would be beneficial to beverage dispensing manufacturers  
     SUMMARY OF THE INVENTION  
      In accordance with the present invention, an oval carbonator provides a decreased height and an increased exterior surface area for carbonators. The decreased height reduces the amount of material required in a cold plate, while the increased exterior surface area provides additional heat removal capability. The oval shape further provides an increased liquid/gas interaction area. The oval carbonator further consolidates carbonator components into a single location, therein simplifying tubing runs in an associated cold plate, and reducing manufacturing costs.  
      The invention further includes a film generator assembly for increasing the surface area of a liquid stream for interaction with a gas. A corresponding method increases the amount of liquid surface area present in the carbonator. The film generator assembly further isolates the incoming liquid and the turbulence associated with the incoming liquid to provide an improved level sensing capability.  
      It is therefore an object of the present invention to provide a carbonator with an oblong shell for a decreased carbonator height.  
      It is a further object of the present invention to provide an increased exterior surface area for additional heat removal capability.  
      It is still further an object of the present invention to provide an increased liquid/gas interaction area in the carbonator for increased carbonator efficiencies.  
      It is still yet further an object of the present invention to provide a film generator assembly to increase the surface area of an incoming liquid stream in the carbonator.  
      It is still yet further an object of the present invention to provide a method for increasing the surface area of a liquid.  
      Still other objects, features, and advantages of the present invention will become evident to those of ordinary skill in the art in light of the following. Also, it should be understood that the scope of this invention is intended to be broad, and any combination of any subset of the features, elements, or steps described herein is part of the intended scope of the invention. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       FIG. 1  provides a perspective view of an oval carbonator according to the preferred embodiment.  
       FIG. 2  illustrates a beverage dispenser including a cold plate and an integral oval carbonator according to the preferred embodiment.  
       FIG. 3  provides an exploded view of the oval carbonator according to the preferred embodiment.  
       FIG. 3   a  provides an exploded view of the orifice housing components according to the preferred embodiment.  
       FIG. 4  illustrates an end view of the oval carbonator according to the preferred embodiment.  
       FIG. 5  provides a cross section view of a film generator assembly according to the preferred embodiment.  
       FIG. 5   a  is a method flowchart for increasing the surface area of a fluid according to the preferred embodiment.  
       FIG. 6  is a method flowchart showing the operation of refilling the carbonator according to the preferred embodiment. 
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT  
      As required, detailed embodiments of the present invention are disclosed herein; however, it is to be understood that the disclosed embodiments are merely exemplary of the invention, which may be embodied in various forms. It is further to be understood that the figures are not necessarily to scale, and some features may be exaggerated to show details of particular components or steps.  
      An oval carbonator minimizes the height required in a cold plate and increases the gas/water interaction area in the carbonator as compared to commonly used circular carbonator designs. The oval carbonator further includes a film generator assembly that more efficiently diffuses the incoming water, thereby promoting increased surface area exposure for interaction with gas in the carbonator. The oval carbonator includes a probe that may be used with a controller to ascertain whether the carbonator requires refilling. The oval carbonator is designed to be used in a cold plate of a beverage dispenser to carbonate water for beverage drinks. Use of the oval carbonator further simplifies the routing of beverage and diluent tubing runs in the cold plate due to its compact design.  
      As shown in  FIGS. 1-6 , an oval carbonator  100  may be integrally cast into a cold plate  310 , wherein the cold plate  310  is used to provide cooling to items in contact with the cold plate  310 , including beverage dispensing lines, diluent lines and the integral oval carbonator  100 . Once cooled, beverage drinks may be dispensed through a beverage dispensing nozzle  305  when an activator  306  is operated. The oval carbonator  100  includes a housing  110 , a probe assembly  250 , and a film generator assembly  260 . The housing  110  includes a shell  120 , a front plate  130  and a back plate  140 . The shell  120 , having a first end  121  and a second end  122 , is of a hollow oblong cross section as shown in  FIG. 4 . The first end  121  and the second end  122  are cut perpendicular to the axis of the shell  120  for simplicity, but could otherwise be at any preselected angle. The second end  122  of the shell  120  includes an exit port  123  to allow a carbonated water pickup tube  142  to pass through the shell  120  during assembly. The front plate  130  and the back plate  140  are of a shape complementary to the openings of the shell  120 , and are suitably mounted to the shell  120  to contain an interior volume of the shell  120 . In most cases, the front plate  130  and the back plate  140  are welded to the shell  120  when outfitted.  
      The front plate  130  includes a first side  135 , a second side  136 , a gas inlet port  138 , and a probe aperture  131 . The probe aperture  131  is of a size suitable to accept an outer diameter of a probe fitting  132 . A front plate assembly  230  includes the front plate  130 , the probe fitting  132 , and a gas inlet tube  148 . A first end  133  of the probe fitting  132  is inserted into the probe aperture  131  of the front plate  130  to a predetermined distance, substantially such that half of the probe fitting  132  is disposed into the aperture  131 . The probe fitting  132  must be suitably connected to the front plate  130 , preferably through a welding process. The second end  134  of the probe fitting  132  further includes a slot  137  for aligning the probe assembly  250 . The first end  133  is in alignment with the first side  135  of the front plate  130 . The gas inlet port  138  is of a size sufficient to accept the gas line  148 . The gas line  148 , in communication with a gas source (not shown), passes through the front plate  130  to enter the housing  110  to deliver gas to the oval carbonator  100 . This connection must also be suitably sealed to allow the carbonator  100  to hold liquids and gases.  
      A back plate assembly  240  includes the back plate  140 , the film generator assembly  260 , a probe guide  144 , an orifice housing  170 , and a water inlet tube  146 . The back plate  140  includes a first side  167 , a second side  168 , a liquid inlet port  171 , and a depression  179 . The liquid inlet port  171  is of a size sufficient to not impede water entering the housing  110  from a water inlet tube  146  and the orifice housing  170 . The orifice housing  170  is of the same form as disclosed in U.S. patent application Ser. No. 10/677,854, filed on Oct. 2, 2003, the disclosure of which is hereby incorporated by reference. The orifice housing  170  includes a first aperture  172 , a second aperture  173  leading to the first aperture  172 , and a fitting  174  that may be removable for cleaning or carbonator  100  tuning situations. The first aperture  172  of the orifice housing  170  is aligned with the liquid inlet port  171  of the back plate  140 . The second aperture  173  is coupled to the water inlet pipe  146 , such that water to be carbonated passes from the water inlet tube  146  through the second aperture  173 , into the first aperture  172 , through an orifice  175  in the fitting  174  and through the liquid inlet port  171  to enter the housing  110 . The orifice housing  170  requires a plug  176  and an o-ring  177  at the exposed end of the first aperture  172  to seal the interior chamber of the carbonator  100 .  
      The film generator assembly  260  includes a hemispherical redirector  163 , and a cylindrical film generator  164 . The film generator  164  includes a first end  161  and a second end  162 . The first end  161  is coupled to the second side  168  of the back plate  140 , whereby the cylindrical shape of the film generator  164  is concentric to the liquid inlet port  171 . As previously disclosed, the redirector  163  is hemispherical in shape, and of a diameter substantially equal to the diameter of the film generator  164 , such that the exposed diameter may be coupled to the second end  162  of the film generator  164 . Coupling of the film generator  164  and the hemispherical redirector  163  may be accomplished through welding. The film generator  164  further includes multiple apertures  165  used to aid in the filming process.  
      The depression  179  is of a size sufficient to accommodate a first end  151  of the probe guide  144 , thereby providing locating aid during assembly. As such, the probe guide  144  may be repeatedly located on the backplate  140  and attached to the backplate  140  using any suitable process, for example, welding. The probe guide  144  further includes evacuation holes  145  near the first end  151  to prevent gas from being trapped in the probe guide  144 .  
      The probe assembly  250  includes a probe housing  251 , a primary probe  252 , a secondary probe  253 , a first insulator  254 , a second insulator  255 , o-rings  256  and a protrusion  257 . The probe housing  251  includes a central aperture  280  that passes through the probe housing  251  from a first end  281  to a second end  282 . The first insulator  254  is disposed in the central aperture  280  of the probe housing  251 . The first insulator  254  includes a primary aperture  283  and a secondary aperture  284 . The primary probe  252  is of shape sufficient to be housed in the primary aperture  283  in the first insulator  254 . The secondary probe  253  is likewise of sufficient diameter to be housed in the secondary aperture  284  of the first insulator  254 . The second insulator  255  also includes a primary aperture  285  and a secondary aperture  286 , wherein the primary probe  252  and the secondary probe  253  similarly pass through the primary aperture  285  and the secondary aperture  286  of the second insulator  255 , respectively. The insulators  254  and  255  provide a mechanism to separate and restrain the probes. The second insulator  255  includes an outer diameter that mirrors the inner diameter of the probe guide  144 . As such, the second insulator  255  slides into the probe guide  144  to center the probes  252  and  253 .  
      The probe housing  251  includes features to accept the o-rings  256  and provide proper sealing. The protrusion  257  is of a size sufficient to slide into the slot  137  of the probe fitting  132  when the probe assembly  250  is located in the probe fitting  132 , further providing a mechanical stop for the probe assembly  250 . A probe nut  258  includes threads  259  to secure the probe nut  258  in the probe fitting  132 , thereby restraining the probe assembly  250  in the confines of the probe fitting  132 .  
      Upon assembly, the first end  133  of the probe fitting  132  is inserted into the first end  121  of the shell  120  and the front plate  130  is welded to the shell  120  to create a portion of a vessel. A first end  183  of the carbonated water pickup tube  142  is then placed into the inner portion of the shell  120 , such that a second end  184  protrudes from the exit port  123  located on the second end  122  of the shell  120 . The back plate assembly  240  may now be aligned with the shell  120  to insert a second end  152  of the guide tube  144  into the second end  122  of the shell  120 . The back plate assembly  240  must be inserted such that the guide tube  144  is in alignment with the probe fitting  132  mounted in the first end  121  of the shell  120 . Once inserted, the back plate assembly  240  may be welded to the shell  120  to further enclose the housing  110 . The welding operations include sealing all mating seams, thereby creating a vessel that will hold pressure. At this point, openings remaining in the vessel include an inner passage  201  of the probe fitting  132 , a passage  202  through the gas inlet tube  148 , a water inlet passage  203  in the water inlet tube  146 , and carbonated water passage  204  through the carbonated water pickup tube  142 .  
      Once the welding of the housing  110  is complete, the probe assembly  250  is installed into the inner passage  201  of the probe fitting  132 . An exposed end of the primary probe  252  is inserted into the guide tube  144 , and the probe assembly  250  is further pushed into the inner passage  201  of the probe fitting  132 . As the probe housing  251  enters the probe fitting  132 , the o-rings  256  engage an inner diameter of the probe fitting  132  to create a seal. The protrusion  257  of the probe housing  251  then enters the slot  137  in the probe fitting  132 , thereby locating the probe assembly  250  in the passage  201 . The probe nut  258  is then installed in the inner passage  201  of the probe fitting  132  to secure the probe assembly  250 .  
      In use, the carbonator  100  is disposed in a cold plate  310 . In this preferred embodiment, the cold plate  310  is disposed within a beverage dispenser  300  at an angle of substantially ten degrees. The carbonator  100 , being substantially parallel with the cold plate  310 , is similarly inclined at substantially ten degrees, with the front plate  130  of the housing  110  nearest a lowest end of the cold plate  310 . The cross section of the oval carbonator  100 , in combination with the slant of ten degrees provides a substantially increased fluid/gas interface area.  
      The oblong shell  120  of the carbonator  100  also increases the exterior surface area of the carbonator  100 , thereby increasing the heat removal capability over the commonly used round cross section shells. The oblong shell  120  further provides for a reduced vertical profile in the cold plate  310 . The reduced vertical height of the oval carbonator  100  reduces the height requirement for the cold plate  310 , thereby minimizing the thickness of the cold plate  310  and the quantity of aluminum required in a cold plate  310 . While this preferred embodiment has been shown with an oblong shell  120 , it should be clear to one skilled in the art that the shape of the shell does not have to be a perfect oblong. An oval or semi-oblong shape may be suitable to provide a decreased vertical height in a cold plate  310 .  
      In most instances, the dispenser  300  includes a controller  301  to conduct dispensing operations, including the operations of the probe assembly  250  in the carbonator  100 . The controller  301  is connectable to the primary probe  252  and the secondary probe  253  to take resistive measurements between the probes and a common ground. Each resistive measurement is representative of a liquid or a gas. The controller  301  then utilizes the information to determine whether the carbonator  100  requires filling, as well as when the carbonator  100  is full.  
      In operation, the gas inlet tube  148  is coupled to a gas regulator (not shown) and ultimately, a gas source (not shown). The water inlet tube  146  is coupled to a boost pump (not shown) and ultimately, a water source (not shown). The carbonated water pickup tube  142  is coupled to delivery tubes that lead to the beverage dispensing nozzle  305  for mixing with beverage syrup. The gas source and the gas regulator provide gas to the housing  110  at a pressure of seventy to eighty pounds per square inch. The gas enters the housing  110  through the gas inlet pipe  148  and occupies the area above any existing water level in the housing  110 . The water source delivers water to be carbonated to the water inlet tube  146 . The water to be carbonated moves from the inner passage  203  of the water inlet tube  146  into the first aperture  172  of the orifice housing  170 , and through the orifice  175  in the removable fitting  174  to enter the liquid inlet port  171  of the back plate  140 . The water entering from the water inlet tube  146  is pressurized to one hundred twenty five to one hundred fifty pounds per square inch by a boost pump (not shown). The pressurized water passing through the orifice  175  in the removable fitting  174  creates a water jet as it enters the housing  110 .  
      As shown in  FIG. 5 , the jet stream is unobstructed until it contacts an inner surface  178  of the hemispherical film generator assembly  260 . The jet stream contacts the inner surface  178  of the hemispherical redirector  163  and is forced to flow along the inner surface  178  of the hemispherical redirector  163  towards the film generator  164 . The film generator  164  includes a plurality of apertures  165  to force the fluid into a film, thereby increasing the exposed surface area of the fluid. The increased surface allows more gas to be absorbed into the liquid. Additional benefits of this type of film generator assembly  260  include the separation of the jet stream, as well as any disruptions in the fluid due to the high pressure jet stream, from the carbonator probes  252  and  253 . Separation of this type minimizes the possibility of erratic readings due to turbulent fluids in the carbonator  100  and better level sensing.  
      As shown in  FIG. 5 , the carbonator  100  includes a Low Level line  181  and a High Level line  182 . When the carbonator  100  is initially started, the carbonator  100  is pressurized to seventy to eighty pounds per square inch through the gas inlet tube  148 . Water at approximately one hundred twenty five to one hundred fifty pounds per square inch is let into the carbonator  100  through the water inlet tube  146 , into the orifice housing  170  and through the orifice  175  in the removable fitting  174  to enter the carbonator  100 . As previously disclosed, the water enters in a jet stream and contacts the film generator assembly  260 , therein creating a film as the fluid momentum forces the water to follow the inner surface  178  of the hemispherical redirector  163  and the cylindrical film generator  164 . When the momentum of the fluid has been exhausted, the fluid moves downward over the cylindrical film generator  164 , and becomes part of the carbonated water supply pool.  
       FIG. 5   a  provides a method flowchart for increasing the surface area of a liquid. Increased surface area in a liquid provides for an increased gas/liquid interaction area. The process begins with step  60 , wherein a liquid is sprayed into a chamber containing a pressurized gas. Once the liquid is sprayed into the chamber, it is redirected through the use of a hemispherical redirector  163  as shown in step  65 . The hemispherical redirector  163  forces the liquid to flow along an inner surface  178  towards the cylindrical film generator  164 . As the fluid flows along the surface of the cylindrical film generator  164 , it turns into a film as it passes over the apertures  165  in the cylindrical film generator  164  as shown in step  70 . The pressurized gas is absorbed by the liquid at all exposed liquid surface areas, step  75 . The amount of gas absorbed by the fluid is directly related to the readily available liquid/gas interface, the decreased fluid temperature, as well as all exposed surface areas due to filming and sprays. The liquid/gas mixture is then stored for use.  
      As the water enters the pressurized carbonator  100 , gas is absorbed into the water, thereby creating carbonated water. After passing through the film generator assembly  260 , the carbonated water pools in the lower portion of the carbonator  100 , to await removal through the carbonated water pickup tube  142  and delivery to a dispensing nozzle  305 . The carbonator  100  continues to be filled until the water level in the carbonator  100  reaches the high level line  182 . Once the high level line  182  is reached, the controller  301  ceases providing power to the carbonator pump motor. In this state, the carbonator  100  will remain pressurized, however, as carbonated drinks are dispensed, the carbonated water level decreases. When the carbonated water level falls below the low level line  181 , the controller  301  commences to provide power to the carbonator pump motor to refill the carbonator  100  to the high level line  182 .  
       FIG. 6  provides a method flowchart for the carbonator probe operations. The process commences with step  10 , the start position. Once the process is started, the controller  301  moves to step  20 , wherein the controller  301  commences to monitor the primary and secondary probes  252  and  253  at a predetermined interval, every one tenth of a second in this preferred embodiment. The process then moves to step  30 , wherein the controller  301  determines whether the primary probe  252  reading is representative of a liquid. If the reading is not representative of a liquid, the process moves to step  40 , wherein the controller  301  determines if the secondary probe  253  reading is representative of a liquid. If the reading in step  40  is representative of a liquid, the controller returns to step  20  to continue sampling. If the reading in step  40  is not representative of a liquid, the controller  301  provides power to the carbonator pump motor to refill the carbonator  100 .  
      If the reading in step  30  is representative of a liquid, the process moves to step  35 , wherein the controller  301  determines if the carbonator pump motor is on. If the carbonator pump motor is not on in step  35 , the controller  301  returns to step  20  to continue the sampling of the probes. If the carbonator pump motor is on in step  35 , the process moves to step  45 , wherein the controller  301  turns the carbonator pump motor off. The controller  301  then returns to step  20  to continue sampling.  
      After turning the carbonator pump motor on in step  50 , the process moves to step  55 , wherein the controller  301  determines if an off signal has been received. If an off signal has been received in step  55 , the controller  301  moves to step  58 , the end. If an off signal has not been received in step  55 , the process returns to step  20 , wherein the controller  301  continues to sample the probes.  
      In summary, the oblong shell  120  provides an improved gas/water interaction area within the confines of the carbonator  100 . The increased cross sectional area provides a larger water surface area, whereby an increased amount of the pressurized gas is exposed to the increased surface area. Further advantages of the oval carbonator  100  include a simplification of the tubing bundles that are cast into the cold plate  310 . The oval carbonator  100  consolidates the volumes previously used by the carbonator, thereby allowing the tubing bundles to be consolidated. Consolidation of this type translates into reduced manufacturing time and increased savings due to the simplified design.  
      Although the present invention has been described in terms of the foregoing preferred embodiment, such description has been for exemplary purposes only and, as will be apparent to those of ordinary skill in the art, many alternatives, equivalents, and variations of varying degrees will fall within the scope of the present invention. That scope, accordingly, is not to be limited in any respect by the foregoing detailed description; rather, it is defined only by the claims that follow.