Patent Publication Number: US-2009223948-A1

Title: Magnetic water heater

Description:
TECHNICAL FIELD 
     The disclosed subject matter relates generally to devices used to heat fluids, and more specifically, to heaters that that utilize magnets to generate heat. 
     BACKGROUND 
     Known water heaters generally utilize electrical heating elements or combustion of fossil fuels to generate heat. Electrical heating elements are known to be inefficient and costly to operate. Fossil fuel combustion is inefficient, costly, and often requires complex and costly exhaust systems to transport exhaust gases to a safe discharge location. 
     Permanent magnet heaters are a known alternative to electrical heating elements and fossil fuel burners. Permanent magnet heaters subject an electrical conductor to a changing magnetic field, thereby producing eddy currents, i.e., a circulating flow of electrons, within the conductor. The flow of the current through the conductor is resisted by the resistance of the conductor, which produces heat. Known magnetic heaters create eddy currents in a stationary conductor by moving permanent magnets relative to a fixed conductor. The heat generated by the eddy currents is then used to heat water. However, a problem exists in that known permanent magnet heaters are inefficient, complex, and cost-prohibitive. 
     SUMMARY 
     A first embodiment of a disclosed heater includes a first rotor and a second rotor rotatably mounted to a support structure so that the first rotor is substantially coaxial with the second rotor. Each rotor has a magnet attached thereto. A tank is at least partially formed from an electrically conductive material and is located between the first and second rotors. The heater further includes a drive mechanism to rotate the first rotor in a first direction and the second rotor in a second direction opposite the first direction. 
     Also disclosed is a water heater having a first rotor and a second rotor rotatably mounted to a support structure so that the first rotor is substantially coaxial with the second rotor. Each of the first and second rotors has a magnet attached thereto. A tank is at least partially formed from an electrically conductive material and is located between the first and second rotors. The heater further includes a storage unit in fluid communication with the tank. A drive mechanism rotates the first rotor and the second rotor in opposite directions to heat the water in the heater tank. Water from the storage unit is passed through the tank to maintain water in the storage unit within a selected temperature range. 
     A disclosed forced air heater includes a first rotor and a second rotor rotatably mounted to a support structure so that the first rotor is substantially coaxial with the second rotor. Each of the first and second rotors has a magnet attached thereto. A tank is at least partially formed from an electrically conductive material and is located between the first and second rotors. The heater further includes a heater core in fluid communication with the tank. Fluid from the heater core is passed through the tank to heat the fluid, and then returned to the heater core, thereby raising the temperature of the heater core. A fan is positioned proximate to the heater core and creates a flow of air across the heater core. 
     This summary is provided to introduce a selection of concepts in a simplified form that are further described below in the Detailed Description. This summary is not intended to identify key features of the claimed subject matter, nor is it intended to be used as an aid in determining the scope of the claimed subject matter. 
    
    
     
       DESCRIPTION OF THE DRAWINGS 
       The foregoing aspects and many of the attendant advantages of this invention will become more readily appreciated by reference to the following detailed description, when taken in conjunction with the accompanying drawings, wherein: 
         FIG. 1  is a side view of an exemplary embodiment of a water heater using a magnetic heater according to the present disclosure; 
         FIG. 2  is an end view of the water heater shown in  FIG. 1 ; 
         FIG. 3  is a side view of a first rotor of the water heater shown in  FIG. 2 ; 
         FIG. 4  is a side view of a second rotor of the water heater shown in  FIG. 2 ; 
         FIG. 5  is a side view of an alternate embodiment of a rotor of the water heater shown in  FIG. 2 ; and 
         FIG. 6  is side view of an exemplary embodiment of a forced air heater using the heater shown in  FIG. 1 . 
     
    
    
     DETAILED DESCRIPTION 
     Referring to  FIGS. 1 and 2 , an exemplary embodiment of a disclosed magnetic heater  10  includes a support structure  12  with a first rotor  20  rotatably coupled thereto by a first axle  22 . The rotor  20  is disk-shaped, and the axle  22  is secured to a side of the rotor  20  so that the axle  22  extends in a perpendicular direction from a central portion of the rotor  20 . 
     A plurality of permanent magnets  24  is disposed on the face of the rotor  20  opposite the side to which the axle  22  is secured. As shown in  FIG. 3 , the magnets  24  are positioned circumferentially around the face of the first rotor  20  and are oriented so the magnets  24  all exhibit the same polarity. In the illustrated embodiment, a plurality of magnet seats are machined into the face of the rotor  20 , and a magnet  24  having a square cross-section is press fit into each magnet seat. It should be appreciated, however, that the magnets  24  can be secured to the rotor by any suitable means, including adhesives, mechanical fasteners, mounting hardware, or any combination thereof without departing from the scope of the disclosure. Further, alternate embodiments that utilize different numbers of magnets  24 , as well as magnets  24  having different sizes, shapes, positions, and orientations should also be considered within the scope of the disclosed subject matter. 
     Referring back to  FIG. 2 , a second rotor  30 , which is similar to the first rotor  20 , is rotatably mounted to the support structure  12  by an axle  32 . The second rotor  30  is disk-shaped, and the axle  32  is secured to a side of the rotor  30  so that the axle  32  extends in a perpendicular direction from the center of the rotor  30 . The second rotor  30  is mounted to the support structure  12  so that the face of the second rotor  30  opposes the face of the first rotor  20 . When the second rotor  30  is so mounted, the axles  22  and  32  of the first and second rotors  20  and  30  extend in opposite directions, and are substantially coaxial with each other. 
     As shown in  FIGS. 2 and 4 , a plurality of magnets  34  is disposed on the face of the second rotor  30  opposite the side to which the axle  32  is secured. Similar to the magnets  24  of the first rotor  20 , the magnets  34  of the second rotor  30  are positioned circumferentially around the face of the rotor  30  and are oriented so that all of the magnets  34  exhibit the same polarity; however, the polarity exhibited by the magnets  24  disposed on the first rotor  20  is opposite to the polarity exhibited by the magnets  34  disposed on the second rotor  30 . Although the polarities of the magnets  24  of the first rotor  20  and the magnets  34  of the second rotor  30  are opposite, the number and arrangement of magnets  34  in the illustrated embodiment are the same as the number and arrangement of the magnets  24  on the first rotor  20 . Alternate embodiments are contemplated, wherein the number and arrangement of magnets  24  and  34  vary between the first and second rotors  20  and  30 , respectively, and such embodiments should be considered within the scope of the present disclosure. 
     In an alternate embodiment of the first and second rotors  20  and  30 , magnets disposed on the face of a given rotor exhibit opposite polarities. Referring to  FIG. 5 , the magnets  24  positioned circumferentially around the face of the first rotor  20  are oriented so that adjacent magnets  24  on the face of the rotor  20  exhibit opposite polarities. Similarly, the magnets  34  positioned circumferentially around the face of the second rotor  30  are oriented so that adjacent magnets  34  on the face of the second rotor  30  exhibit opposite polarities. 
     Referring back to  FIG. 2 , a tank  40  is disposed between the first and second rotors  20  and  30 . In the disclosed embodiment, the tank  40  has opposing parallel walls, each wall corresponding to and being generally parallel to one of the first and second rotors  20  and  30 . The tank  40  is constructed of an electrically conductive material, such as copper, and is located in close enough proximity to the first and second rotors  20  and  30  so that relative motion between either rotor  20  or  30  and the tank  40  produces eddy currents in the tank material. In alternate embodiments, only the portions of the tank  40  positioned near the rotors  20  and  30  are formed from an electrically conductive material. 
     The heater  10  includes a drive system  50  for rotating the rotors  20  and  30  relative to the tank  40 . The illustrated drive system  50  includes a first motor  52  secured to the support structure  12  and a pulley  56  coupled to the drive shaft of the motor  52 . A belt  54  forms an endless loop that engages the pulley  56  coupled to the drive shaft of the motor  52  and also, a second pulley  56  coupled to the axle  22  of the first rotor  20 . As a result, rotation of the drive shaft turns the belt  54 , which in turn rotates the axis  22  and the first rotor  20 . 
     As shown in  FIGS. 1 and 2 , the drive system  50  further includes a second motor  58  secured to the support structure  12  and a pulley (not shown) coupled to the drive shaft of the second motor  58 . A second belt  60  forms an endless loop that operably engages the pulley coupled to the drive shaft of the second motor  58  and also, a pulley  62  coupled to the axle  32  of the second rotor  30 . In operation, the first motor  52  drives the first pulley  56  to rotate the first rotor  20  in a first direction, and the second motor  58  drives the second pulley  62  to rotate the first rotor in a second direction that is opposite the first direction. 
     Various embodiments of the drive assembly are possible and should be considered within the scope of the disclosure. In one exemplary embodiment, the motors  52  and  58  are powered by a DC current from a standard power supply. In alternate embodiments, the motors  52  and  58  are powered by one or more batteries  94  that are charged by solar panels  96 , thus eliminating the need for an external power supply. In yet another alternate embodiment, the belts  54  and  60  and the pulleys  56  and  62  are replaced with gears, chains and sprockets, a direct coupling to the motor drive shaft, or any other know method of transmitting rotational force from the motor drive shaft to the rotor axles  22  and  32 . In addition, a single motor is optionally adapted to drive both rotors  20  and  30 . 
     As the first and second rotors  20  and  30  rotate in opposite direction, the motion of the magnets  34  and  24  associated with each rotor create a magnetic vortex inside the tank  40 . The magnetic vortex, in turn, induces eddy currents in the conductive portions of the tank  40 . Heat created by the eddy currents increases the temperature of the tank  40 . As a result, water or any other fluid inside the tank is heated. 
     The rotational speed of the first and second rotors  20  and  30  differs for various embodiments. In one exemplary embodiment, the rotors  20  and  30  rotate at a speed of between 1500 and 1700 revolutions per minute. It should be appreciated, however, that the rotational speed of the rotors  20  and  30  can be varied to optimize performance for a particular embodiment. 
     The described heater  10  is suitable for use in several applications. In the embodiment shown in  FIG. 1 , the magnetic heater  10  is used to maintain water  70  in a storage unit  72  at an elevated temperature. Water  70  is discharged from the storage unit  72  and is received into the tank  40  of the heater  10  via an intake pipe  74 . A water pump  76  is provided to pump the water  70  from the storage unit  72  to the tank  40 . Alternately, the storage unit  72  is positioned above the tank  40  so that water  70  passes from the storage unit  72  to the tank  40  via gravity feed. 
     Water  70  from the storage unit  72  is heated in the tank  40  of the magnetic heater  10 . The heated water is discharged from the tank  40  and is returned to storage unit  72  via a hot water outlet pipe  78 . When water  70  from the storage unit  72  is used, replacement water is supplied to the storage unit  72  by a replacement water inlet  80 . The replacement water mixes with the water  70  in the storage unit  72 , and is subsequently heated by the magnetic heater  10 . By utilizing a thermostat to control the frequency and rate at which water from the storage unit  72  is removed, heated, and returned to the storage unit  72 , the temperature of the water  70  in the storage unit  72  can be maintained within a desired range. 
     In an alternate embodiment, the magnetic heater  10  is used to heat a swimming pool so that the temperature of the water is maintained within a desired range. This embodiment is configured similar to the previously described embodiment in which water is a storage unit  72  is heated, with main difference being that a swimming pool takes the place of the previously described storage unit  72 . Other modifications to adapt the system for use with a swimming pool would be within the knowledge of one of skill in the art and should be considered within the scope of the present disclosure. 
       FIG. 6  shows still another alternate embodiment, in which the magnetic heater  10  is adapted to be used with a known heater core  90  in a forced air heater. The magnetic heater  10  heats fluid within the heater core  90 , and a fan  92  blows air across an external portion of the heater core  90 . The resulting flow of heated air can be used to heat a building, such as a home, thereby replacing or supplementing a standard furnace. As a result, embodiments that use motors powered by batteries  94  charged by solar panels  96 , as shown in  FIG. 6 , can heat houses or other buildings without burning fossil fuels or requiring an outside power source. 
     While illustrative embodiments have been illustrated and described, it will be appreciated that various changes can be made therein without departing from the spirit and scope of the invention.