Abstract:
A lamp having a light emitting diode, a pettier device, a heat sink, a translucent thermally conductive window, and an optical fluid. The pettier device is in thermal communication with the light emitting diode and converts a waste thermal energy discharged by the light emitting diode into an electrical energy. Conductors transfer the electrical energy from the pettier device to a boost circuit which converts a level of a voltage associated with the electrical energy output from the pettier device to a higher, more useful value. The heat sink transfers a second thermal energy from the pettier device. The optical fluid is located between the translucent thermally conductive window and the light emitting diode. The optical fluid has an angle of diffraction having an intermediate value relative to an angle of diffraction associated with the light emitting diode and an angle of diffraction associated with the translucent thermally conductive window.

Description:
CROSS-REFERENCE TO RELATED APPLICATION 
       [0001]    The present invention claims the benefit of U.S. Provisional Patent Application No. 61/117,827 filed Nov. 25, 2008, the contents of which are incorporated herein by reference. 
     
    
     TECHNICAL FIELD 
       [0002]    The present invention relates to the powering and regeneration of waste heat generated by light sources. More particularly, the present invention relates a method to reclaim the thermal energy using the reclaimed energy to stabilize the operating temperature and/or generate an electrical energy. 
       BACKGROUND OF THE INVENTION 
       [0003]    Wasted heat generated by the operation of light sources, including, but not limited to, LED&#39;s is always a problem for designers for light source and fixture designers. A method is needed to reclaim thermal energy. 
       SUMMARY OF THE INVENTION 
       [0004]    A first aspect of the invention is directed to a lamp. The lamp comprises: a means for illumination; a means for converting a waste thermal energy from the means for illumination in thermal communication with the means for illumination wherein the means for converting the waste thermal energy converts the waste thermal energy into an electrical energy; a means for conducting the electrical energy from the means for converting the waste thermal energy; a means for converting a level of a voltage associated with the electrical energy output from the means for converting the waste thermal energy; a heat sink for transferring a second thermal energy from the means for converting the waste thermal energy; a translucent thermally conductive window; and an optical fluid between the translucent thermally conductive window and the means for illumination, the optical fluid having an angle of diffraction having an intermediate value relative to an angle of diffraction associated with the means for illumination and an angle of diffraction associated with the translucent thermally conductive window. 
         [0005]    A second aspect of the present invention is directed to a lamp comprising: a light emitting diode; a peltier device in thermal communication with the light emitting diode wherein the peltier device converts a waste thermal energy discharged by the light emitting diode into an electrical energy; a means for conducting the electrical energy from the peltier device; a means for converting a level of a voltage associated with the electrical energy output from the peltier device; a heat sink for transferring a second thermal energy from the peltier device; a translucent thermally conductive window; and an optical fluid between the translucent thermally conductive window and the light emitting diode, the optical fluid having an angle of diffraction having an intermediate value relative to an angle of diffraction associated with the light emitting diode and an angle of diffraction associated with the translucent thermally conductive window. 
         [0006]    A third aspect of the present invention is directed to a light fixture. The light fixture comprises: a means for illumination; a housing having a chamber in which the means for illumination is at least partially within; a fluid carrying conduit in thermal communication with the means for illumination; a fluid pressure within the fluid carrying conduit wherein a waster thermal energy from the means for illumination causes a heated fluid pressure within the fluid carrying conduit; a means for converting a thermal energy radiating from fluid pressure into an electrical energy; a means for conducting the electrical energy from the means for converting the thermal energy from the fluid pressure; a means for converting a level of a voltage associated with the electrical energy output of the means for converting the thermal energy from the fluid pressure; and a heat sink for transferring a second thermal energy from the means for converting the waste thermal energy. 
         [0007]    A fourth aspect of the present invention is directed to a lamp. The lamp comprises: a means for illumination; a means for converting a thermal energy to an electrical energy; and a means for conducting the electrical energy from the means for converting. 
         [0008]    This aspect of the invention may include one or more of the following features, alone or in any reasonable combination. This aspect may further comprise: a heat sink. The means for illumination may be a light emitting diode in thermal communication with the means for converting the thermal energy, and a waste thermal energy from the light emitting diode may be transferred to the means for converting the thermal energy. The heat sink may receive a second waste thermal energy from the means for converting the thermal energy. This aspect may further comprise: a translucent thermally conductive window. This aspect may further comprise: an optical fluid between the translucent thermally conductive window and the means for illumination. This aspect may further comprise: a fluid carrying conduit in thermal communication with the means for illumination; and a fluid pressure within the fluid carrying conduit wherein the fluid pressure is adapted to receive a transfer of a thermal energy from the means for illumination. The fluid pressure may be in thermal communication with the means for converting a waste thermal energy to an electrical energy, a thermal energy may be transferable from the fluid pressure to the means for converting a waste thermal energy to an electrical energy. This aspect may further comprise: a means for converting a level of a voltage associated with the electrical energy output of the means for converting the thermal energy. This aspect may further comprise: a microcontroller for controlling an operation of the means for converting a level of a voltage. The means for converting a level of a voltage may be a boost circuit wherein a voltage associated with the electrical energy output of the means for converting the thermal energy is increased to a second voltage by the boost circuit. This aspect may further comprise: a reflector defining a chamber in which the means for illumination is at least partially within, the means for illumination being a metal halide lamp; a fluid carrying conduit in thermal communication with the means for illumination; a fluid pressure within the fluid carrying conduit wherein the fluid pressure is adapted to receive a transfer of a thermal energy from metal halide lamp wherein the fluid pressure is in thermal communication with the means for converting a waste thermal energy to an electrical energy and wherein a thermal energy is transferable from the fluid pressure to the means for converting a waste thermal energy to an electrical energy; and a means for converting a level of a voltage associated with the electrical energy output of the means for converting the thermal energy. 
         [0009]    Another aspect of the present invention is directed to a method to extract thermal energy from lighting fixtures. The method comprises the step of: using a plurality of modes of recovery comprising thermal couples, fluids used in a carnot cycle and peltier generators wherein the extracted thermal energy is used to either improve the overall operational cycle efficiency or to do other useful work such as fixture thermal management. 
         [0010]    This aspect of the invention may include one or more of the following features, alone or in any reasonable combination. A thermal flow may be directed through a thermal-electrical recovery device comprising a peltier junction wherein the plurality of modes direct a thermal energy flow from a means for illumination to a heat sinking reservoir. A recovered energy may be reconverted to usable energy/voltage levels and recycled to a power input to the means for illumination and reused in a primary function of the light fixture. A boost circuit may be provided to increase a recovered energy level to a usable level by the light fixture. The light fixture may include a flat clear thermal conducting material to laterally redirect a thermal energy to a recovery area. A fluid having an intermediate index of refraction may be adapted to increase an optical transfer between layers. One quarter wave coatings may be used to reduce internal reflections. The recovered energy may be used to operate auxiliary attachments to enhance, communicate or redirect energy flows in and around the prime source operating object. The recovered energy may be divided between enhancement functions and regeneration to the prime operating object. A thermal energy from the means for illumination may be used either summated or fractionalized to drive a working fluid in a carnot-type thermal cycle for altering a local thermal gradient to enhance work space via recovered energies. A thermal energy stored in the working fluid may be stored for time displaced usage or other recovery via low head turbines or other methods thermal-fluid manipulation. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0011]    To understand the present invention, it will now be described by way of example, with reference to the accompanying drawings in which: 
           [0012]      FIG. 1  is a mechanical scenario showing an LED mounted to a Peltier junction; 
           [0013]      FIG. 2  is a block diagram of an energy flow in the mechanical apparatus; 
           [0014]      FIG. 3  is an illustration of a recovered energy being fed to a conversion means; 
           [0015]      FIG. 4  is a circuit diagram showing a method of energy possible conversion technique; 
           [0016]      FIG. 5  is a block diagram illustrating a maximum energy transfer criteria; 
           [0017]      FIG. 6  is a flowchart for a maximum power transfer; and 
           [0018]      FIG. 7  is a diagram illustrating a converted energy used for emergency lighting and forced cooling; 
           [0019]      FIG. 8  is a diagram illustrating a fixture showing two scenarios with Peltier junctions  44  and with heat exchanger with working fluid pipes; 
           [0020]      FIG. 9  is a diagram of a room showing thermal gradient with lighting fixtures  50  working fluid conduits  51  and heat exchanger  45  for creating exaggerated thermal gradient at lower working level  52 ; and 
           [0021]      FIG. 10  is a graph showing natural thermal gradient  46  in a room in  FIG. 9  and an exaggerated distribution by recapturing waste heat to drive heat exchanger  45 . 
       
    
    
     DETAILED DESCRIPTION 
       [0022]    While this invention is susceptible of embodiments in many different forms, there is shown in the drawings and will herein be described in detail preferred embodiments of the invention with the understanding that the present disclosure is to be considered as an exemplification of the principles of the invention and is not intended to limit the broad aspect of the invention to the embodiments illustrated. 
         [0023]    The present invention relates to the powering and regeneration of waste heat generated by light sources. The invention includes a method to reclaim a thermal energy from any heat source to mechanical or electrical conversion technique and then using the reclaimed energy to: 1) use the reclaimed energy to keep the light source in a state of ideal operational equilibrium such as stabilize the operating temperature via a fan of or other devices powered from the waste heat; and 2) convert the waste heat to an electrical energy to a level that a lamp drive can reuse and improve the system efficiency—how much light for a given input wattage. 
         [0024]    Methods for conversion of heat energy are well known in the art. Examples of such methods include thermal piles consisting of thermal couples, Peltier devices, and secondary conversion methods such as phase changes in a working fluid—the working fluid being used to drive other cooling or generating means. A readily available mechanism is a Peltier junction. 
         [0025]    Referring to  FIG. 1 , a device  100  of the present invention is illustrated. This device  100  comprises, a light emitting diode (“LED”)  1  mounted, or electrically joined, by any good thermal conductive means to a heat converting means, preferably a peltier device  2  having voltage output leads  3 , thermal conductors such as heat conducting channels  4 , a thermally conductive window  5 , and a heat sink  6 . This device includes a front side cooling method of the LED junction  1  via the thermally conductive window  5 , which is preferably optically clear, and a redirection of the thermal energy to the heat converting means  2  through heat conducting channels  4 . No conversion method is 100% in its operation so a heat will be typically given off to remove what remains of the unconverted energies. 
         [0026]    In  FIG. 1 , the thermally conductive window  5  is immediately in front of, and in contact with, a front side of the LED  1 . The contact may be the front side window alone or in conjunction with an optical fluid  12  to reduce boundary reflection in the optical transmission path. This optical conduction matching is accomplished by providing a medium that has an angle of diffraction that is of an intermediate value to the path through the LED  1  optical path and the window&#39;s  5  value. 
         [0027]      FIG. 2  shows the flow of energies  11  in the above device  100 . In this case, a heat source, the LED  1 , is shown attached to the conversion platform with a heat sink for un-captured heat removal. Peltier junctions  2  have thermal differentials of about, but not limited to, 10 to 100 degrees Celsius. This differential is made by the heat source  1  and the heat energy flow is characterized by a quantity E source . As shown in  FIG. 2 , the heat flows  11  from greater temperature to the lower temperature. In creating this thermal disequilibrium and resulting heat flow  11  in the Peltier junction  2  extracts a part of this energy flow as electrical energy. Equation 10 shows the energy balance of the operation E e  is the portion of the energy flow  11  made available. 
         [0000]        E   source   =E   e   +E   sink   (10)
 
         [0028]    This action has the ancillary effect of reducing size and cost of heat sinks  2  to remove the un-captured heat by a level proportional to amount of energy conducted out of the flow as electrical energy. 
         [0029]    Also, since the converter  2  is typically symmetric in its operation from heat-to-electrical conversion, it can be used as an electrical-to-heat device. In this case, stored energy would be used to drive heat away from the system shown in  FIG. 1 . The purpose of this is to actively stabilize the LED  1  temperatures where the peltier junction  2  is driven so as to produce a thermal gradient that enhances heat flow away from the junction  2  for short periods of times if the LED  1  were pushed close to non-optimal operation. 
         [0030]      FIG. 3  is flow diagram showing the voltage leads from the peltier junction  14  being applied to a converter  13  to transform the energy to a level where it is regenerated into to power input supplying the light source power supply  16 . The transformation is by any number of boosting or bucking techniques known in the art. 
         [0031]    A converter  200  as illustrated in  FIG. 4  is one method the recovered energy may be boosted to a new level. The voltage  14  from the peltier junction  2  causes current to flow into the inductor L Boost    18  during the on-time of switch  19 . The gate voltage shown in  21  is applied to initiate conduction in the switching element  19  for a period of time to store energy derived from the peltier junction  2 . Capacitor  20  is provided to store energy. Diode  17  redirects the energy onto the capacitor  20 . 
         [0032]    The on-time P W    22  is controlled by any number of control schemes known in the art to control the boost cycle for optimal energy transfer. However, maximum energy transformation, as derived from the maximum energy transfer, specifies that when the voltage drop across the load is equal to the voltage drop across the internal series impedance. 
         [0033]      FIG. 5  illustrates an equivalent circuit for the peltier junction  2 . The voltage generated Vj  14  is the voltage generated by the junction in series with a series impedance  24 . This supplies energy to the load impedance Rload  25 . 
         [0034]    To actively achieve maximum transfer, the boost circuit  200  of  FIG. 4  could be driven from a microcontroller  300  (see  FIG. 2 ) using the program flow shown in  FIG. 6 . A sample  27  would be taken while the Vj is not loaded, e.g. the off time of the gate drive the processor, taking a reading of the unloaded source  14 . This value would be averaged as stored  28  as the open circuit value. When the gate drive is present, another sample  29  would be made to capture the loaded value that would represent the time variant load that a circuit will represent to the peltier source of  FIG. 5 . A single sample at the mid point of the drive cycle Pw  22 , or a series of samples averaged over the entire on-time of the drive, can yield an indication of loading factor for operation at maximum transfer. This loaded value is then stored  30 . A comparison step  31  is then conducted to see if the load voltage is ½, of the open circuit voltage. The decision tree would either direct the drive to increase in duty cycle to increase  32  the loading, decrease the duty cycle to decrease the loading  33 , or make no adjustment and loop back to the beginning  34  and continue monitoring. 
         [0035]    Output from the boost circuit may be used to power external elements  400  (see  FIG. 2 ), such as fans, other illuminating means, circuits, microprocessors, etc. 
         [0036]      FIG. 7  shows a configuration where the output  38  of the peltier junction  2  is fed into a converter that can either direct the energy into a storage device, e.g., but not limited to, a battery. Should the battery become completely charged then the excess could be regenerated as previously described. Should power be lost the circuit could switch its power source to the energy stored in the batteries. 
         [0037]    Referring to  FIGS. 8 and 9 , another application of heat recycling may be used in conjunction with high intensity light sources (HID) such as metal halide lamps. Each lamp could be a source for hundreds of watts. One implementation could be peltier junctions  44  mounted to a reflector  50  defining a chamber in which the lamp is at least partially housed. As described above, the peltier junctions  44  feed the recovered energy to a lamp drive circuit or use a direct form of conversion to use the waste heat for another purpose such as thermally stratifying a working area. This can work in an installation or room  42  with high ceilings where most HID lighting is located. This example illustrated shown in  FIG. 9 . A thermal gradient  43  will naturally occur in any space with heat sources. The temperature T 1  and T 2  in the thermal gradient  43 , if not actively interfered with, will be such that T 1  will be greater than T 2 . An effect caused by lower density hot air rising and colder air falling. To assure that the most heat is directed to the peltier junction  2 , a method may be employed to conduct heat away from the source from 2 sides of the light source  41 . This method can be used to cool a work area  52 . 
         [0038]      FIG. 10  shows two gradients  46  and  47 . In gradient  46  is seen a native thermal distribution providing a uniform distribution from the floor temperature to ceiling temperature. In gradient  47  the gradient has a small increase in the early part of the curve then increases more quickly as the height increases. The gradient illustration shows that it could be possible to accentuate the gradient at reduced heights 8 feet and below where people work while at the same time not changing the net gradient significantly. This is achievable by running a working fluid through the reflector  50  as shown in  FIG. 8 , for example by a fluid pressure within a conduit  51  in thermal communication with the light source  41 . This fluid is of a typical type used in Carnot cycle refrigeration systems; however, its energy source is the waste heat or thermal energy of the HID lighting much like refrigerators that use a natural gas heat source for cooling. The arrangement is shown in  FIG. 9 , the fixtures  50  would heat and pressurize the working fluid where it would be directed to cooling component  45  of the Carnot cycle device. This cold air would be released at the lower level creating a cold strata and thereby create the exaggerated gradient of  FIG. 10  gradient  47 . 
         [0039]    While the specific embodiments have been illustrated and described, numerous modifications come to mind without significantly departing from the spirit of the invention and the scope of protection is only limited by the scope of the accompanying Claims.