Abstract:
A cooling system using a heat differential power system and apparatus for cooling and generating mechanical and/or electrical power in a system are presented. A number of embodiments are presented. In each embodiment a heat differential power system is implemented which dissipates heat created by heat-generating components, such as, but not limited to, microprocessors, within the system and utilizes the heat differential created between the heat generating components and other parts of the system as power to operate the heat differential power system and convert thermal energy into other forms of energy such as, but not limited to, mechanical, and/or electrical energy for powering desired systems such as, but not limited to, fans, or other electrical components, and/or extending the battery life in a portable system.

Description:
CROSS REFERENCE TO RELATED APPLICATIONS  
       [0001]     The present application is a Continuation-in-Part application of U.S. patent applications Ser. No. 11/017,024 filed on Dec. 20, 2004 entitled “Heat Differential Power System” and U.S. patent application Ser. No. 11/240,863 filed Sep. 30, 2005 and also entitled “Heat Differential Power System”. 
     
    
     BACKGROUND OF THE INVENTION  
     Description of the Related Art  
       [0002]     Portable computing and telecommunication devices are increasingly being used. At the heart of these devices are processors and other heat-generating components which are becoming increasingly more powerful and which, as a result, are requiring more power to operate and generating more heat in operation. More sophisticated methods is needed for cooling these heat generating components in these systems as well as heat generating components in a wide variety of other applications and system.  
         [0003]     When these devices are used in portable mode, there is an ever increasing demand on the battery for power, which in turn shortens the battery life. Moreover, in portability mode, these devices are often at rest on a person&#39;s lap or in close contact with other parts of the body and it is not desirable to have increasing amounts of heat in such close contact with the human body.  
         [0004]     An additional environmental problem is that the increasing amounts of heat generated by these heat generating components results in additional amounts of wasted energy.  
         [0005]     The additional heat being generated by these heat-generating components has other detrimental effects. For example, it can cause component malfunctions or shut-downs and lower the useful life of the components themselves and the device as a whole.  
         [0006]     Heat differential power sources or engines such as the Stirling engine have been known and available for some time. They operate on the principal that thermal energy can be converted to other forms of energy such as mechanical or electrical energy and make use of a difference in temperature between two or more points, areas or locations to make this conversion.  
         [0007]     Thus, there is a need in the art for a sophisticated method and apparatus for cooling heat generating components. There is a need in the art for a method and apparatus for reducing the power consumed by these systems, particularly in portability mode. There is a need in the art for a method or apparatus for extending the battery life and thus the operational time of these devices in portability mode. There is a need in the art for a method or apparatus to conserve or utilize wasted thermal energy. There is a need in the art for a method or apparatus used to cool the heat generating components, conserve and utilize the thermal energy and/or to extend the battery life which can be deployed within the small footprint available in the case or housing of a system, such as a laptop computer, standalone computer, cellular telephone, an engine or any system with heat generating components. There is a need in the art for an optimal, cost-effective method and apparatus for cooling heat generating components which allows the heat generating component to operate at the marketed operating capacity, and which is effective in portability mode for the device or system.  
       SUMMARY OF THE INVENTION  
       [0008]     A method and apparatus for cooling one or more heat generating components in a system including a heat differential power system; a hot contact thermally coupling one or more heat generating components to the heat differential power system; and a cold contact for thermally coupling a region of the system cooler than the heat generating components to the heat differential power system. A variety of heat differential power-based cooling systems are implemented.  
         [0009]     The cooling system as described above wherein the heat differential power system includes a housing containing a gas and having a surface thermally coupled to the hot contact and having another surface thermally coupled to the cold contact; a first piston disposed within the housing for alternately moving the gas toward the surfaces causing the gas to expand as it nears the surface thermally coupled to the hot contact and to contract as it nears the surface thermally coupled to the cold contact; a second piston disposed within or adjacent to the housing which responds to the alternate expansion and contraction of the gas for powering the first piston; and means coupled to the pistons for receiving the mechanical motion of the second piston and providing the first piston with mechanical motion.  
         [0010]     The cooling system as described above wherein the cooling power of the system is increased or decreased by increasing or decreasing, respectively, the surface areas of the housing coupled to the hot contact and the cold contact.  
         [0011]     The cooling system as described above having additional surface area means thermally coupled to the surfaces of the housing coupled to the hot contact and/or coupled to the cold contact, said additional surface area means providing additional cooling power to the cooling system.  
         [0012]     The cooling system as described above wherein the cooler region of the system is the casing of the system.  
         [0013]     The cooling system as described above for powering one or more air flow devices for the system.  
         [0014]     The cooling system as described above further including a heat dissipating device coupled to one or more heat-generating components for providing additional cooling of the heat-generating components.  
         [0015]     The cooling system as described above for conserving electrical energy in the system.  
         [0016]     The cooling system as described above for generating electrical energy in the system.  
         [0017]     The cooling system as described above wherein the system is disposed within the casing of the system.  
         [0018]     The cooling system as described above wherein the first contact is a thermal spreader for spreading the heat from hot spots of one or more the heat generating components.  
         [0019]     A method of cooling heat generating components in a system having a heat differential power system by thermally coupling a heat differential power system to one or more heat generating components and thermally coupling a region of the system cooler than the heat-generating components to the heat differential power system.  
     
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0020]      FIG. 1  displays top, cross-sectional view of a system view of a cooling system disposed in a system housing, such as a data processing system housing, for example, and implemented in accordance with the teachings of the present invention.  
         [0021]      FIG. 2  displays a sectional view of a heat differential power system disposed within a system housing and implemented in accordance with the teachings of the present invention.  
         [0022]      FIG. 3  displays yet another sectional view of a heat differential power system disposed within a system housing and implemented in accordance with the teachings of the present invention.  
         [0023]      FIG. 4  displays yet another sectional view of a heat differential power system disposed within a system housing and implemented in accordance with the teachings of the present invention.  
         [0024]      FIG. 5  displays a sectional view of a heat differential power system disposed within a system housing and connected to an air flow device and implemented in accordance with the teachings of the present invention.  
         [0025]      FIG. 6  displays a sectional view of a heat differential power system disposed within a system housing having a flywheel with magnets disposed thereon and induction coils disposed in close proximity to the magnets as they rotate for generating electrical power and implemented in accordance with the teachings of the present invention.  
         [0026]      FIG. 7  displays a sectional view of a heat differential power system disposed within a system housing having a flywheel with induction coils disposed thereon and magnets disposed in close proximity to the induction coils as they rotate for generating electrical power and implemented in accordance with the teachings of the present invention.  
     
    
     DETAILED DESCRIPTION  
       [0027]     While the making and using of various embodiments of the present invention are discussed in detail below, it should be appreciated that the present invention provides many applicable inventive concepts, which can be embodied in a wide variety of specific contexts. The specific embodiments discussed herein are merely illustrative of specific ways to make and use the invention and do not limit the scope of the invention.  
         [0028]     Although the present invention is described herein in the context of cooling heat generating components in a wide range of data processing systems and telecommunication systems, it will be understood that the present invention applies to any system or application for cooling heat generating components. In the present invention, heat produced by a heat generating component, such as a microprocessor, for example, is dissipated by a cooling system which also converts otherwise wasted thermal energy into mechanical and/or electrical power to be used by the system. The present invention may be utilized in any computing, communications, personal convenience applications, engines, industrial systems, mechanical systems, etc. For example, the present invention could be implemented in a variety of personal computers which are portable or stationary, cell phones, and personal digital assistants (PDAs). The present invention is equally applicable to any number of heat-generating components (e.g., central processing units, digital signal processors, lasers, engine parts or any heat generating component that requires cooling) within such systems. For purposes of explanation and illustration, the present invention is hereafter described primarily in reference to a central processing unit (CPU) within a portable personal computer such as a laptop.  
         [0029]     Referring now to  FIG. 1 , a cross-sectional, top view of a data processing system  100  is depicted with a heat generating components  104  and  105  that are cooled by the heat differential power system  200  depicted in  FIG. 2 . The data processing system  100 , shown in part only in  FIG. 1 , comprises a housing  101  such as a computer cabinet or case, a main circuit board  102  such as a motherboard, heat generating component(s)  104  and  105 , such as a microprocessor, which are in direct thermal contact with a heat collector  103 . The heat collector  103  is coupled to the heat differential power system in  FIG. 2 . The heat collector  103  can be made from a variety of materials that have good thermal transfer characteristics, such as copper. In  FIG. 1 , the heat collector can be a wide variety of shapes and thickness as suited to a particular application. The different configurations would be obvious to one skilled in the art. One embodiment, of the heat collector is a comparatively thin, rectangular piece of copper thermally coupled to the heat generating components  104  and  105  by a thermally conductive means of which a wide variety of metals or compounds are available such as thermal heat sink compound paste.  
         [0030]     In operation, heat generated by the heat generating components  104  and  105 , is transferred to the heat collector  103  and then on to the heat differential power system  200  where it is used to create the temperature differential to operate the heat differential power system  200  and where heat is dissipated in the process. The heat differential power system  200  is similar to a Stirling engine and uses thermal differentials to operate. This heat differential power system  200  is depicted in  FIGS. 2-6 . In  FIG. 1 , the heat differential power system  200  acquires the thermal energy to operate through the heat collector  103 .  
         [0031]     In  FIG. 1 , an air-cooled device  106 , such as a heat sink, is also depicted. The air cooled device  106  is thermally coupled to heat generating component  105  via the heat collector  103  and provides additional cooling of heat generating component  105 . In this example, heat collector  103  also acts as a heat spreader to spread the heat generated by hot spots of the heat generating components  104  and  105 . This also enables the cooling device, of which one embodiment is an air cooled device, to do a more efficient job of cooling.  
         [0032]     It will be understood that the present invention encompasses embodiments where no air cooled device is used. Thus, if incremental cooling in addition to that provided by the heat collector  103  and the heat differential power system  200  is not needed for one or more of the heat generating components, no air cooled device, including air cooled device  106  would be used. Conversely, if heat generating component  104  required additional cooling, an air cooled device can be added and thermally coupled to heat generating component  104 . Additionally, a single air cooled device could be used to provide additional cooling of both heat generating components. Alternatively, if substantial, additional cooling power is required, the heat differential power system  200  itself can be adjusted as will be explained subsequently and used with or without an air cooled device such as air cooled device  106 .  
         [0033]     It will also be appreciated that the present invention includes a variety of coupling techniques used to thermally couple the heat collector  103  and the air cooled device  106  to the heat generating components. For example, the heat collector  103  may be thermally coupled to a different surface, such as the bottom, of the heat generating components  104  and  105  while the air cooled devices are coupled to top surface of the heat generating component  105 . This arrangement would provide cooling to two different surfaces of one or more of the heat generating components further increasing the cooling power of the system  100 .  
         [0034]      FIG. 2  is a cutaway frontal view of a heat differential power system according to the present invention. The heat differential power system  200  operates when there exists a thermal differential (temperature difference) from one side  201  of the power system  200  to the other side  204 . Very small differentials are needed to start and operate the engine. A very precisely made small power system  200  could operate from the heat emitted by one&#39;s hands at normal room temperature. As the thermal differentials become greater, the power system  200  produces more power.  
         [0035]     The power system  200  includes a sealed housing  215  having a hot side  204 A and  204 B and a cold side  201 . The hot side  204 A and  204 B are thermally connected to the heat collector  103 . The cold side  201  is thermally connected to a cooler region such as the data processing system casing  101 , as shown in  FIG. 1 . It should be noted that the cold side may be thermally connected to other points in the system and the hot side may be connected to other points of the heat generating components so long as there is a temperature differential. It is preferred, however, to have these thermal connections to points where there is sufficient temperature differential to generate the desired power from the heat differential power system  200 .  
         [0036]     A piston  202  moves back and forth toward the hot side  204 A and  204 B and cold side  201  of the housing. As the piston moves toward the cold side  201 , it displaces a gas inside the housing  215  toward the hot side  204 A and  204 B which causes the gas to expand. As the piston  202  moves toward the hot side  204 A and  204 B, it displaces the gas in the housing  215  toward the cold side  201  which cause the gas to contract. The expansion of the gas pushes piston  206  away (or outward) from the housing. The contraction of the gas, on the other hand, creates a vacuum like pulse which pulls piston  206  toward (or inward) the housing  215 . It will be understood that a wide variety of gases, including air, and combinations thereof may be used in the housing to optimize the particular application.  
         [0037]     Piston  202  is not sealed in the chamber  215 , which allows gas to be displaced from the cold side  201  to the hot side  204 A and  204 B and vice versa.  
         [0038]     Piston  206  is sealed in the chamber  205  by a low-friction, precision fit. The chamber  205  should be of an appropriate size and shape to fit the particular application and is shown in the figures as a cylinder. Sealing rings may also be used to seal piston  206  as it moves in the chamber  205 . The inward and outward motion of the piston  206  is converted to rotating motion by connecting a rod  207  to a crankshaft disc  210 . The crankshaft disc  210  is connected to a crankshaft  209 . The crankshaft  209  is connected to a flywheel  212 , which rotates and moves a connecting rod  213  in and out. The connecting rod  213  is connected to piston  202  causing it to move alternately toward and away from the hot side  204 A and  204 B and the cold side  201  in the housing  215 . The connections of rod  207  to disc  210  and rod  213  to flywheel  212 , respectively, are made so as to insure the correct timing of pistons  206  and  202 , respectively. It should be appreciated that other means and other forms of movement can be used to convert the inward and outward movement of piston  206  to mechanical and/or electrical energy and that these other forms are within the scope of the present invention.  
         [0039]     The heat collector  103  transfers heat to side  204 A&amp;B of housing  215  which creates the hot side. The side  201  of housing  215  may be a plate or other suitable device which is in thermal contact with the casing  101  of the data processing system  100  shown in  FIG. 1  and thus form the cold side of the housing  215 .  
         [0040]     Bearing support  208  is a post or other suitable shape that holds a bearing  211  that supports the rotating crankshaft  209 . Bearing block  214  supports and atmospherically seals the connecting rod  213  as it cycles in and out of the housing  215  and drives piston  202  back and forth within the housing  215 . It is important to note that connecting rods  207  and  213  during operation will have to bend or flex slightly during each cycle. This flexing can be accomplished by inserting a flexible joint, or by utilizing a sufficiently flexible material to construct connecting rods  207  and  213  as would be obvious to one skilled in the art.  
         [0041]     Heat generating component  216  is a microprocessor disposed within the data processing system  100 . One or more heat generating components  216  can be thermally connected to the heat collector  103 . Heat generated by component(s)  216  is transferred to heat collector  103  and thermally coupled to the hot side  204 A and  204 B of the housing  215 . An optional air cooled device  106  is also shown in  FIG. 2  and disposed on the heat collector  103  to provide additional cooling of heat-generating component  216 .  
         [0042]     In operation, heat transferred from the heat generating component  216  to the heat differential power system  200  via heat collector  103  is dissipated by the heat differential power system  200 , thereby cooling heat generating component  216 . If substantial, additional cooling power is required, the surface areas of the hot side  204 A and  204 B of the heat differential power system  200  and the surface area of the cold side  201  of the heat differential power system may be increased. This will result in the dissipation of substantial additional heat from the heat generating component  216 . Moreover, further heat dissipation power or cooling power can be achieved by adding fins, channels, ripples or any method or providing additional surface area for heat dissipation to the interior or exterior or any combination there of, of sides  204 A,  204 B and  201  of housing  215 . In  FIG. 2 , fins  217  are depicted on the interiors of sides  204 A,  204 B and  201  as an example.  
         [0043]      FIG. 3  represents a view of the heat differential power system  200  in  FIG. 2  from the flywheel  212  perspective. In  FIG. 3 , the heat differential power system  200  is shown. Also depicted is the cold side  201  of sealed housing  215 ; the hot side  204 A and  204 B of housing  215  and piston  202  for displacing the gas within the housing  215 .  
         [0044]     In  FIG. 3 , bearing support  208  is a post or other suitable shape that holds a bearing that supports the crankshaft  209 . Flywheel  212  is connected to the crankshaft  209 . Connecting rod  213  connects the flywheel  212  to the piston  202 , Bearing block  214  supports and atmospherically seals housing  215  as the connecting rod  213  cycles in and out of the chamber  215 . It should be appreciated that other means and other forms of movement can be used to convert the inward and outward movement of piston  206  to mechanical and/or electrical energy and that these other forms are within the scope of the present invention.  
         [0045]      FIG. 4  is a crankshaft  209  side view of the heat differential power system  200 . In  FIG. 4 , the housing  215 , the cold side  201 , the hot side  204 A and  204 B, the piston  202 , the bearing support  208 , the crankshaft  209 , the flywheel  212  are depicted similarly as in  FIG. 3 . In  FIG. 4 , piston  206  is also depicted as well as chamber  205  for atmospherically sealing piston  206  and housing  215 , and connecting rod  207  for converting the inward and outward motion of piston  206  to rotating motion applied to crankshaft disc  210 . It should be appreciated that other means and other forms of movement can be used to convert the inward and outward movement of piston  206  to mechanical and/or electrical energy and that these other forms are within the scope of the present invention.  
         [0046]      FIG. 5  depicts yet another view, similar to  FIG. 2  of the heat differential power system  200 . In  FIG. 5 , the printed circuit board  102  of  FIG. 1  such as the motherboard is depicted with a heat generating component  533  such as a microprocessor, disposed thereon. The heat collector  103  disposed on the component  533  thermally couples heat to the hot side  204 A and  204 B of the power system housing  215 . Also depicted in  FIG. 5  is an air flow device  538 , such as a fan. Within the air flow device  538 , a blade assembly  535  is disposed for circulating air through the system  100 , such, as for example, directly over the heat generating component  533  or the heat generating components  104  and  105  and air cooled device  106  depicted in  FIG. 1 . A rotating connecting rod  536  is connected to the crankshaft  209  of the heat differential power system and also connected to the impeller  535  for rotating the blade assembly within the air flow device  538 . It shall be understood that connecting rod  536  may be a separate piece connected to the crankshaft  209  or may be just an extension of the crankshaft  209 . It should also be appreciated that, it is within the scope of this invention, that a wide variety of methods can be used to transfer or convert power or energy produced by the heat differential power source, such as, but not limited to, electrical, mechanical, magnetic or other as needed to suite a particular application. Such embodiments would be obvious to one skilled in the art. For example, the flywheel  212  may be modified to include blades and thereby act as an air flow device in addition to its other functions. In this example, connecting rod  536 , airflow device  538  and blade assembly  535  may be eliminated or left in the system to provide yet additional air flow if desired. Another example would include modifications to connecting rods  207  and/or  213  such that the movement of these connecting rods in the system creates air flow. It will be appreciated then that current invention may act as both a cooling system and an air flow system and generates its own power (from otherwise wasted thermal energy) to provide air flow and/or power.  
         [0047]      FIG. 6  is a flywheel side view of the heat differential power system  200  as shown in  FIG. 3 . Magnets  650 A and  650 B are attached to the flywheel  212 . Coils  651 A and  651 B are coils of wire that form a complete circuit, so that electrical flow can enter on one conductor  652 A, then pass through a continuous coil of wire  651 A and  651 B, and then exit on the other conductor  652 B in the pair,  652 A and  652 B depicting wires that form the ends of coils  651 A and  652 B. The magnets  650  rotate with the flywheel  212 . As each magnet travels past the coil of wire  651 , a small electrical power pulse is produced. It should be appreciated that multiple magnet and coil arrangements could be placed around any rotating component, and should not be limited to the two as depicted in  FIG. 6 . Similarly, it should be understood that flywheel  212  need not be used for the magnet  650  and coil  651  assemblies, but that any device connected to the crankshaft  209  can be utilized. It should also be appreciated that, it is within the scope of this invention, that a wide variety of methods can be used to transfer or convert power or energy produced by the heat differential power source, such as, but not limited to, electrical, mechanical, magnetic or other as needed to suite a particular application. Such embodiments would be obvious to one skilled in the art.  
         [0048]      FIG. 7  is a flywheel side view of the heat differential power system  200  as shown in  FIG. 3 . Coils  651 A and  651 B are attached to the flywheel  212  for movement past stationary magnets  650 A and  650 B. The flywheel  212  is provided with a commutator surface  659  attached to the crankshaft disc  210  for passing generated electrical power from the rotating coils  651 A and  651 B, through electrical conductors  652 A and  652 B to the commutator  659 . The electrical energy is then passed through spring loaded brushes  670 A and  670 B and then exit to an electrical circuit through conductors  658 A and  658 B. The commutator  659  is attached to the outside diameter of the crankshaft disc  210 . It should be appreciated that a wide variety of configurations could be used for the commutator arrangement to suit the particular design criteria. It is even contemplated that the flywheel could be replaced by a linear induction power generator with the magnets and coils arranged for relative linear movement with respect to one another. An advantage of such a linear induction power generator is that it can be inserted into narrower spaces that a flywheel arrangement. It should also be appreciated that a rotating arrangement does not have to be used, and that anywhere on the heat differential power system where a magnet can be arranged to repeatedly pass by a coil, or a coil can be arranged to repeatedly pass by a magnet, electron flow can be induced, as with the rotating arrangement to create electrical energy.  
         [0049]     The arrangements of  FIG. 6  and  FIG. 7  can be utilized to reclaim a small amount of electrical energy from the heat differential power system  200  when the power system  200  is running at high speed. This reclamation and conversion of power is highly desirable in portable battery-operated systems to extend the time of operation of the portable system. Similarly, the electrical power generated by this arrangement could be used to help power one or more mechanical devices such as fans for additional cooling. It should also be appreciated that like most power generating units with the proper placement of magnets and coils, the arrangements in FIGS.  6  and  FIG. 7  of the coils  651 A and  651 B in combination with the magnets  650 A and  650 B could act as a motor to rotate the flywheel. It should be appreciated that this same configuration can be used as a brake to slow, hold, or stop the rotation of the flywheel if desired for a specific purpose.  
         [0050]     The present invention reduces the amount of electrical energy required to operate the system  100  by keeping the heat generating components cooler. It also conserves energy by transforming otherwise wasted thermal energy into mechanical and/or electrical energy. The present invention also minimizes medical concerns of overly hot portable devices in contact with the operators.  
         [0051]     Thus, the present invention has been described herein with reference to a particular embodiment for a particular application. Those having ordinary skill in the art and access to the present teachings will recognize additional modifications, applications, and embodiments within the scope thereof.  
         [0052]     It is, therefore, intended by the appended claims to cover any and all such applications, modifications, and embodiments within the scope of the present invention.