Abstract:
A device by which one can extract low grade thermal energy and transfer that thermal energy from one medium to another utilizing a Stirling engine compressor means, motor means, heat exchanger means and regeneration chamber. The flow of thermal energy between the two heat exchanger means utilized is reversible by the simple change in direction of rotation of the motor means.

Description:
BACKGROUND OF THE INVENTION 
     This invention pertains to apparatus for transferring heat energy from one medium to another and more particularly to apparatus for providing the reversible heating/cooling of an interior space. 
     The present invention is a device by which one can extract low grade thermal energy and transfer that thermal energy to another medium. Traditionally, this is now being done with a single piston heat pump. The present invention can be reversed but without the complicating reversing valve as is standard with a heat pump. 
     SUMMARY OF THE INVENTION 
     In accordance with the present invention, a compressor is provided with a cylinder or cylinders that contains two pistons driven by a reversible motor means through a rhombic drive means. The configuration of the cylinder and its two pistons is that of a Stirling engine. The Stirling engine, which has been well-known for over 100 years, possesses a reversible heat-to-mechanical energy conversion process which allows it to be utilized as a refrigerator or heat pump. The cylinder of the Stirling engine has two ports each connected to a heat exchanger means with a regeneration chamber connecting the two heat exchanger means to each other. The regeneration chamber has an interior mass composed of a material that possesses high thermal conductivity such as copper filings, which filings are used to absorb heat and cold extremes flowing between the two heat exchanger means. The heat exchanger means can be of a variety of configurations employing different heat transfer mediums such as water, oil, glycol, air, etc. The present invention is a closed loop system that can employ a variety of gases such as helium, argon, freon and air to be used in the compressor cylinder. 
     Since Boyle&#39;s Law determines that the compression of a gas increases the temperature of that gas and the decompression of a gas results in a decrease in temperature of that gas, the movement of the two pistons in the cylinder as defined by the rhombic drive means results in a large variation in temperatures between the two heat exchanger means connected to the cylinder. One of the heat exchanger means connected to the cylinder will have a cooler ambient temperature and the other heat exchanger means connected to the cylinder will have a warmer ambient temperature. It is a feature of the present invention that the heating/cooling procedure is reversible by the simple means of reversing the direction of the motor means driving the pistons in the cylinder without the need of a reversing valve. 
     The heat transfer unit described in the present invention can be employed in any place that a typical compressor means is used in a heating or cooling system. It can be used in a wide range of industrial, commercial or residential heating, cooling, heat reclaiming or storage systems. Other objects and advantages of the invention will become apparent from the disclosure. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     FIG. 1 is a side view of the preferred embodiment of the invention; 
     FIG. 2 is a perspective view of the preferred embodiment of the invention in the Heating Mode; 
     FIG. 3 is a perspective view of the preferred embodiment of the invention in the Cooling Mode; 
     FIG. 4 is a side view partially in section of the compressor cylinder during the compression cycle in the Heating Mode; 
     FIG. 5 is a side view partially in section of the compressor cylinder during the heat transfer cycle in the Heating Mode; 
     FIG. 6 is a side view partially in section of the compressor cylinder during the decompression cycle in the Heating Mode; 
     FIG. 7 is a side view partially in section of the compressor cylinder during the displacement cycle in the Heating Mode; 
     FIG. 8 is a side view partially in section of the compressor cylinder during the decompression cycle in the Cooling Mode; 
     FIG. 9 is a side view partially in section of the compressor cylinder during the displacement cycle in the Cooling Mode; 
     FIG. 10 is a side view partially in section of the compressor cylinder during the compression cycle in the Cooling Mode; 
     FIG. 11 is a side view partially in section of the compressor cylinder during the heat transfer cycle in the Cooling Mode; and 
     FIG. 12 is a cross-sectional view of the cylinder showing the relationship of the pistons with their respective connecting rods and subsequent sealing means. 
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     Although the disclosure hereof is detailed and exact to enable those skilled in the art to practice the invention, the physical embodiments herein disclosed merely exemplify the invention which may be embodied in other specific structure. The scope of the invention is defined in the claims appended hereto. 
     Referring to FIGS. 1-3, an apparatus 1 is illustrated that includes one embodiment of the present invention. 
     The illustrated embodiment comprises a cylinder 2 inside which travels a displacer piston 3 and a power piston 4 driven by a reversible motor means 5 through a flywheel 7, right angle gear reducer means 8 and rhombic drive means 6. Attached to the cylinder 2 are two ports, middle port 9a and end port 9b, to which are connected heat exchanger means 10, 11. One of the heat exchanger means 11 is preferably mounted on an exterior wall 21 of the enclosure to be heated or cooled. The two heat exchanger means 10, 11 in turn are connected together by means of a regeneration chamber 12. Attached in conjunction with the heat exchanger means 10, 11 are air circulation means, not shown, which allow passage of air over the heat exchanger means 10, 11 for the transfer of thermal energy between the heat exchanger means 10, 11 and ambient air. Further attached to the cylinder 2 is a buffer cylinder 18 mounted behind the power piston 4 and in communication therewith to relieve the vacuum and compression of air behind the power piston 4. This is necessary to ensure smooth operation of the compressor as the area in the cylinder 2 connected to the buffer cylinder 18 is sealed by the power piston and end 36 of the cylinder 2. 
     The rhombic drive system 6 changes rotary motion provided by the motor means 5 through the flywheel 7 and right angle speed reducer means 8 into linear motion for the movement of the power piston 4 and the displacer piston 3 in the cylinder 2. 
     The rotary motion is converted to linear motion as follows. The upper gear 15 of the rhombic drive means 6 is driven by the speed reducer means 8. In turn, the lower gear 14, having an axis parallel to upper gear 15, is driven by the upper gear. Each of the gears 14 and 15 has a peg 14a and 15a, respectively, protruding from the side thereof parallel to the axis from the respective gear. Each such peg is positioned near the outer edge of the respective gear, and positioned with respect to each other so that they are always vertically aligned. Two links, a forward upper link 16a and a rearward upper link 16b are pivotally attached to peg 15a. Similarly, two links, a forward lower link 16c and a rearward lower link 16d are pivotally attached to peg 14a. The distal ends of the forward upper link 16a and the forward lower link 16c are both pivotally connected to a forward clamp block 17a. Similarly, the rearward upper link 16b and the rearward lower link 16d are commonly connected at their distal ends to rearward clamp block 17b. Forward clamp 17a is affixed to a power piston connecting rod 19, in turn connected to the power piston 4. The rearward clamp block 17b is affixed to a displacer piston connecting rod 20. Displacer piston connecting rod 20 is smaller in diameter than power piston connecting rod 19. Power rod 19 is hollow, and displacer rod 20 runs slidably through rod 19 axially, and connects to displacer piston 3. 
     Referring to FIGS. 4-7, the apparatus provides heating by the following method: 
     As shown in FIG. 4, the motor means 5 is set in motion in such a direction as to cause the lower gear 14 of the rhombic drive means 6 to rotate in the clockwise direction. This causes the power piston 4 to move toward the displacer piston 3 in the direction indicated by arrow 22 reducing the volume and thus compressing the gas between the power piston 4 and the displacer piston 3 in the area of the cylinder 2 indicated by space 23. The ambient temperature of the gas found in the space 23 of cylinder 2 is raised by the work done by the power piston 4 compressing the gas in space 23 of cylinder 2. 
     Referring to FIG. 5, the continual clockwise rotation of the lower gear 14 of the rhombic drive means 6 results in the displacer piston 3 moving toward the power piston 4 in the direction indicated by arrow 24. This results in the heated gas found in the space 25 in the cylinder 2 being sent through the middle port 9a, through the heat exchanger means 10 and into the regeneration chamber 12. Due to the high thermal conductivity of the material in the regeneration chamber 12 and nature&#39;s attempt to maintain a state of equilibrium, the internal temperature of the regeneration chamber 12 is raised. In the same manner, the heated gas flowing through the heat exchanger means 10 results in the transfer of thermal energy from the heat exchanger means 10 to the ambient air surrounding the heat exchanger means 10. Cool gas in heat exchanger means 11 is drawn into the space 13 behind the displacer piston 3. 
     Referring to FIG. 6, the continued clockwise rotation of the lower gear 14 of the rhombic drive means 6 results in the power piston 4 moving away from the displacer piston 3 in the direction indicated by arrow 26. This results in the decompression of the gas found in space 27 of cylinder 2. The decompression of the gas results in a loss of thermal energy and subsequent cooling of the gas in space 27 of cylinder 2. 
     Referring to FIG. 7, the completion of the continued clockwise rotational cycle of the lower gear 14 of the rhombic drive means 6 results in displacer piston 3 moving away from the power piston 4 in the direction indicated by arrow 28. This results in cool gas found in space 29 of the cylinder 2 being sent through the end port 9b, through heat exchanger means 11 and into the regeneration chamber 12. Thermal energy is transferred from the ambient air around the heat exchanger means 11 to the cool gas being drawn into the heat exchanger means 11 to maintain a state of thermal equilibrium in the heat exchanger means 11. The gas that had previously been in the regeneration chamber 12 is sent into heat exchanger means 10. The gas drawn from heat exchanger means 11 into the regeneration chamber 12 is raised in temperature by the transfer of thermal energy from regeneration chamber 12 to maintain a state of thermal equilibrium in the regeneration chamber 12. The completion of the clockwise rotational cycle of the lower gear 14 of the rhombic drive means 6 results in the transfer of thermal energy from the ambient air surrounding heat exchanger means 11 to the ambient air surrounding heat exchanger means 10. 
     Referring to FIGS. 8-11, the apparatus provides cooling by the following method: 
     As shown in FIG. 8, the motor means 5 is set in motion in such a direction as to cause the lower gear 14 of the rhombic drive means 6 to rotate in the counter-clockwise direction. This causes the power piston 4 to move away from the displacer piston 3 in the direction indicated by arrow 16. This results in the decompression of the gas found in space 17 of cylinder 2. The decompression of the gas in space 17 of cylinder 2 results in the loss of thermal energy and subsequent cooling of the gas in space 17 of cylinder 2. 
     Referring to FIG. 9, the continued counterclockwise rotation of the lower gear 14 of the rhombic drive means 6 results in the displacer piston 3 moving toward the power piston 4 in the direction indicated by arrow 30. This moves the cool gas found in space 31 of cylinder 2 through port 9, through heat exchanger means 10 and into the regeneration chamber 12. The ambient air around heat exchanger means 10 is reduced in temperature in an attempt to achieve a state of thermal equilibrium between the cool gas in heat exchanger means 10 and the ambient air around it. The ambient temperature of the regeneration chamber 12 is also reduced in like manner. 
     Referring to FIG. 10, the continued counter-clockwise rotation of the lower gear 14 of the rhombic drive means 6 results in the power piston 4 moving toward the displacer piston 3 in the direction indicated by arrow 32. This results in the compression of the gas in space 33 of cylinder 2. The ambient temperature of the gas in space 33 of cylinder 2 is raised by the work done by the power piston 4 compressing the gas in space 33 of cylinder 2. 
     Referring to FIG. 11, the completion of the continued counter-clockwise rotational cycle of the lower gear 14 of the rhombic drive means 6 results in the displacer piston 3 moving away from the power piston 4 in the direction indicated by arrow 34. This moves the heated gas in space 35 of cylinder 2 through port 9, through heat exchanger means 11 and into regeneration chamber 12. Thermal energy of the gas in heat exchanger means 11 is lost to the ambient air surrounding heat exchanger means 11 in an attempt to achieve thermal equilibrium between the gas in the heat exchanger means 11 and the ambient air around heat exchanger means 11. Thermal energy of the gas in the regeneration chamber 12 is reduced in an attempt to achieve thermal equilibrium between the thermally conductive material in the regeneration chamber 12 and the heated gas. The completion of the counterclockwise cycle of the lower gear of the rhombic drive means 6 results in the transfer of thermal energy from the ambient air surrounding heat exchanger means 10 to the ambient air surrounding heat exchanger means 11. 
     In order to ensure that the cylinder 2 operates properly during the compression and decompression of the gas in the system, means must be provided to seal the system against leaks. Referring to FIG. 12, sealing means 37 is provided on the displacer piston 3 and the power piston 4 to prevent the loss of pressure between the pistons 3, 4 and the cylinder wall 38. These may consist of rings placed in circumferential grooves in the pistons 3, 4 that are in direct contact with the cylinder wall 38. Sealing means 39 is provided at the junction of power piston 4 and the displacer piston connecting rod 20 to prevent the loss of pressure at the junction where the displacer piston connecting rod 20 traverses through the power piston 4. Further sealing means 40 is provided at the junction of the displacer piston connecting rod 20 and the hollow power piston connecting rod 19 to prevent the loss of pressure at the junction where the displacer piston connecting rod 20 travels through the power piston connecting rod 19. 
     Thus, it is apparent that there has been provided, in accordance with the invention, a reversible mode heating and cooling system for the heating and cooling of an interior space that fully satisfies the objects, aims and advantages set forth above. While the invention has been described in conjunction with specific embodiments thereof, it is evident that many alternatives, modifications and variations will be apparent to those skilled in the art in light of the foregoing description. Accordingly, it is intended to embrace all such alternatives, modifications and variations as fall within the spirit and broad scope of the appended claims.