Abstract:
A fluid heating system in which the electromagnetic field on both sides of a single induction work coil is utilized to heat two separate but connected chambers simultaneously.

Description:
FIELD OF THE INVENTION  
         [0001]    The present invention relates to novel and useful induction heating systems and, in particular, to such heating systems for fluid heating and steam generation.  
         BACKGROUND OF THE INVENTION  
         [0002]    In my U.S. Pat. No. 5,773,797, I teach a steam generating system in which a first induction coil is powered to heat water in a first chamber producing saturated steam that is directed to a second chamber where a second induction coil is powered to superheat the steam. The teachings of that patent, to the extent relevant to the invention described herein, are incorporated herein by reference as if fully set forth.  
           [0003]    In the present invention, I teach a fluid heating and steam generating system in which a single induction coil is disposed to heat the contents of two chambers simultaneously, thereby achieving results in a highly efficient manner.  
         SUMMARY OF THE INVENTION  
         [0004]    While prior art induction coil heating systems typically use only a portion of the electromagnetic field from an induction work coil for heating, and shield or otherwise prevent the rest of the field from inadvertently heating elements not meant to be heated, the present invention uses substantially all of the field from a coil for productive heating. By strategically locating an induction work coil between two heating chambers or elements, the present invention teaches apparatus and methods by which the field from a single induction coil simultaneously heats two separate chambers and thereby achieves the primary goal of the invention.  
           [0005]    Accordingly, it is an object of the present invention to produce heating in two chambers with a single induction work coil wherein substantially all of the field from the coil is used for productive heating.  
           [0006]    The invention possesses other objects and advantages, especially as concerns particular characteristics and features thereof which will be better understood from the following detailed description of the preferred embodiments when read in conjunction with the appended drawing figures. 
       
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0007]    [0007]FIG. 1 is a sectional side view of one embodiment of the invention in which an electromagnetic field from a single coil causes heat to be generated in two separate chambers simultaneously;  
         [0008]    [0008]FIG. 2 is a sectional side view of an alternative embodiment to FIG. 1 with a different steam discharge port;  
         [0009]    [0009]FIG. 3 is a sectional side view of an alternative embodiment of the invention of FIG. 2 wherein heating elements are disposed in each of the separate chambers;  
         [0010]    [0010]FIG. 4 is a sectional side view of an alternative embodiment of the invention used as a boiler in which the separate chambers are concentric cylinders;  
         [0011]    [0011]FIG. 5 is a top view of FIG. 4 taken along the line A-A;  
         [0012]    [0012]FIG. 6 is a sectional side view of an alternative embodiment of the invention in which heating cores are disposed in chambers which are concentric cylinders; and  
         [0013]    [0013]FIG. 7 is a top view of FIG. 6 with a portion broken away to better illustrate the interior. 
     
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS  
       [0014]    Referring to FIG. 1, in one embodiment of the invention, a heating system  11  includes a first heating chamber  12  having walls  13  and an interior space  14  disposed in the proximity of an induction work coil  16 . The electromagnetic field from the coil  16  (not shown), when it is energized by an RF source  17 , interacts with and causes heating eddy currents in the wall  13  of chamber  12 , causing heat to be generated and transferred to the interior  14  of the chamber  12 . Fluid, such as water  18 , contained in the chamber  12  is thereby heated. A second heating chamber  21  having walls  22  and an interior space  23  is also disposed in the proximity of the induction work coil  16  so that its electromagnetic field interacts with the chamber wall  22  inducing eddy currents therein which produce heat which is transferred to the chamber interior  23 .  
         [0015]    A conduit  24  connects the interior  14  of chamber  12  with the interior  23  of chamber  21  by which steam  25  formed in chamber  12  can migrate into chamber  21  where it can be superheated before exiting through exit channel  26 . A deflection plate  20  attached to channel  26  where it opens into chamber  21  causes the steam from chamber  12  to dwell in chamber  21  long enough to be superheated before exiting through channel  26 . The deflector plate  20  has the general shape of the chamber  21  and sized to leave an opening between its perimeter (or at least a portion thereof) and the chamber wall  22  through which steam can enter that portion of chamber  21  from which it can directly exit channel  26 .  
         [0016]    In this embodiment of the invention, both the conduit  24  and the channel  26  pass through the middle of induction work coil  16 , although other configurations are within the scope of the invention as illustrated in FIG. 2.  
         [0017]    Providing water  18  to first chamber  12  and maintaining a proper water level are all well within the skills of the art, as well as fully explained in my U.S. Pat. No. 5,773,797.  
         [0018]    A primary advantage of the present invention is that the electromagnetic field (not shown) induced in induction work coil  16  is used to simultaneously heat the interior spaces  14  and  23  of the two heating chambers  12  and  21 , respectively.  
         [0019]    Referring to FIG. 2, in an alternative embodiment of the invention, an exit channel  27 , rather than passing through the center of the induction work coil  16 , extends out the bottom of the second chamber  21 . In all other respects, the embodiments are the same, and, in particular, the first heating chamber  12  and the second heating chamber  21  are disposed relative to the induction work coil  16  so that both interact with the electromagnetic field established in the coil  16  to produce heating within both chambers  12  and  21 . A deflection plate  30  adjacent the conduit  24  where it opens into chamber  21  causes the steam from chamber  12  to dwell in chamber  21  long enough to be superheated.  
         [0020]    Referring to FIG. 3, in this embodiment of the invention, as in the two previously described embodiments, the first chamber  12  and the second chamber  21  are both disposed relative to the induction work coil  16  so that they interact with the electromagnetic field produced by the coil  16  when energized by the RF source  17 .  
         [0021]    In this embodiment, however, the walls  13  and  22  of the chambers  12  and  21 , respectively, are not made of a material in which eddy currents or other heating activity occurs by virtue of interaction with an electromagnetic field. Instead, a heating element  31  is disposed within the interior  14  of the first chamber  12  and a similar heating element  32  is disposed within the interior  23  of the second chamber  21 . Heating elements  31  and  32  are made of a ferrous or other induction capable material in which heating eddy currents are induced by the electromagnetic field produced by the induction work coil  16 . Material most advantageously used for the heating elements  31  and  32  are carbon and carbon plate. In this embodiment, the heating element  32  also functions as a deflector as described above in connection with deflector  20 .  
         [0022]    Thus, in this embodiment, as the electromagnetic field from the induction work coil  16  induces eddy currents in heating elements  31  and  32 , the water  18  in the first chamber is heated into steam which passes through conduit  24  to the second chamber  21  where it is further heated into superheated steam which then exits through channel  27  in the bottom of the second chamber  21 .  
         [0023]    Once again, the single heating coil  16  is positioned so that its electromagnetic field interacts with and causes heating in both the first chamber  12  and the second chamber  21 .  
         [0024]    Referring to FIGS. 4 and 5, a boiler  50  embodying the present invention has a first chamber  41  formed by cylindrical, spaced-apart walls  42  and  43  defining an interior space  44 . Chamber  41  surrounds a second chamber  46  formed by a circular wall  47  defining an interior space  48 . In a space  52 , between chambers  41  and  46 , is an induction work coil  51  which, when powered by an RF source (not shown), induces eddy currents in the walls  43  and  47  thereby producing heat in the chambers  41  and  46 . A third chamber  53  formed by wall  54 , which can be an extension of wall  42 , and defining interior space  56  forms a means for connecting the interior spaces  44  and  48  of chambers  41  and  46 , respectively.  
         [0025]    Once again, the coil  51  is disposed relative to the two chambers  41  and  46  so that both are heated simultaneously to heat the fluid in chambers  41  and  46  by the efficient use of induction work coil  51 . When the fluid is water or the like, steam is produced.  
         [0026]    The steam from space  56  can be used for a variety of commercial purposes, such as, for example, processing foods. The invention is useful for a water heater (boiler), steam generator, thermal fluid heater or fryer, to name just a few. In all cases, the present invention provides the advantage of efficiency in the use of energy.  
         [0027]    Referring to FIGS. 6 and 7, in this embodiment of the invention, a system  61  for producing superheated steam includes a cylindrical outer chamber  62  which surrounds an inner cylindrical chamber  63 . The outer chamber  62 , has a cross-section in the shape of a torus, formed by outer cylindrical wall  64  and concentrically spaced-apart inner wall which define an interior space  67  which is supplied with water  68  by a valve  76 . The level of the water  68  is maintained at a predetermined level in a manner well known in the art and which need not be described herein.  
         [0028]    Disposed within the interior space  67  of chamber  62  is a cylindrical heating core  71  having a toroidal cross-section and formed of a ferrous or other induction capable material having a plurality of channels  72  formed therein which run longitudinally from the top  73  to the bottom  74  of the heating core  71 , providing pathways by which water introduced by pump  76  can flow from the bottom of outer chamber  62  to the top of that chamber.  
         [0029]    The concentric inner chamber  63  is formed by a cylindrical wall  78  that is co-axial with first chamber walls  64  and  66  and spaced apart from wall  66 .  
         [0030]    A cylindrical inner core member  81  is disposed within the inner chamber  63  and is formed from a ferrous or other induction capable material. A plurality of channels  82  extend from the top  83  to the bottom  84  of the core  81  and provide pathways for steam to pass from the upper portion  85  of inner chamber  63  to the lower portion  86  of chamber  63  from which the steam can exit through channel  87  that connects with the inner chamber  63 .  
         [0031]    Disposed in the space  91  between the outer chamber wall  66  and the inner chamber wall  78  is an induction work coil  92  which, when energized by an RF source (not shown), produces an electromagnetic field that simultaneously causes the inner core member  81  and the outer core member  71  to generate heat.  
         [0032]    As previously explained and is well known in the art, the electromagnetic field induces eddy currents in the core members  81  and  71  producing heat. The water  68  in the outer chamber  62  is heated to produce steam which rises into a third chamber  94  which connects the outer chamber  62  to the inner chamber  63 . The steam  95  formed in the outer chamber  62  passes into the inner chamber  63  and is superheated by the core member  81  and is eventually discharged through channel  87  as superheated steam.  
         [0033]    While heating cores  71  and  81  are described in connection with this embodiment of the invention, it will occur to those skilled in the art that the invention could operate without these cores when the chamber walls are heated by an electromagnetic field, as previously described in connection with other embodiments.  
         [0034]    Once again, the invention provides an efficient use of the induction work coil  92  by disposing the heating chambers relative thereto so that the electromagnetic field produced by the coil produces heat in both chambers simultaneously.  
         [0035]    It will be apparent to those skilled in the art that various changes, modifications and alterations in the teachings of the present invention may be contemplated without departing from the intended spirit and scope thereof.  
         [0036]    As such, it is intended that the present invention only be limited by the terms of the appended claims.