JP2009133513A - Stirling cycle apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To obtain higher engine efficiency by increasing the energy of working gas blown from a displacer to an expansion space to effectively stir the working gas in the expansion space. <P>SOLUTION: In this Stirling cycle apparatus 1A, a piston 5 in a first cylinder 3 and the displacer 6 in a second cylinder 4 are made to reciprocate with a phase difference by a crank disc 12, thereby generating a flow of working gas through a regenerator 11 to lower the temperature of the expansion space 8 which one end of the displacer 6 faces. In the displacer 6, a pressure accumulating space 15 is formed to receive the working gas through a working gas inflow port 16 when the external space of the displacer 5 has higher pressure, and inject the working gas to the expansion space 8 through a working gas jet orifice 17 when the expansion space 8 has lower pressure. A one-way valve 18 which inhibits the outflow of the working gas to the outside of the pressure accumulating space 15 is disposed in the working gas inflow port 16. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a Stirling cycle apparatus.

  The Stirling cycle device that converts heat into power in the Stirling cycle or converts power into heat in the reverse Stirling cycle has been developed in recent years and has been put into practical use in many cases. There are many literature examples, and Patent Document 1 can be cited as an example. Patent Document 1 describes a two-cylinder Stirling cycle apparatus called α type, which is used as a refrigeration apparatus.

As a customary heat engine, the Stirling cycle device is required to constantly improve the efficiency, and therefore, many devices have been devised. In the refrigeration apparatus described in Patent Document 1, the expansion displacer has a built-in regenerator, and a working gas turbulent flow generation unit that disturbs the flow of the working gas blown into the expansion space is provided at the inlet / outlet on the expansion space side of the regenerator. Provided. Thus, the inside of the expansion space that generates a low temperature is agitated so that heat transfer between the low-temperature working gas in the expansion space and the inner wall surface of the expansion cylinder can be performed smoothly, thereby improving the refrigeration effect.
JP-A-8-152215

  In the Stirling cycle apparatus described in Patent Document 1, the working gas taken in from one end of the displacer is blown out from the other end of the displacer as it is. . The present invention has been made in view of this point, and the momentum of the working gas blown from the displacer to the expansion space is strengthened so that the working gas in the expansion space is effectively stirred to obtain higher engine efficiency. For the purpose.

  To achieve the above object, according to the present invention, a piston and a displacer are reciprocated in a cylinder with a phase difference from each other by a power source, and the flow of the working gas and the compression and expansion through the regenerator generated thereby cause the displacement of the displacer. In a Stirling cycle apparatus that absorbs heat into a working gas in an expansion space facing one end, the working gas is received inside the displacer through a working gas inlet when the pressure in the outer space of the displacer is higher, and the expansion space This is characterized in that a pressure accumulation space is formed in which working gas is ejected into the expansion space through the working gas outlet when the pressure becomes lower.

  According to this configuration, the working gas taken into the displacer is not immediately blown out, but the pressure accumulation space formed inside the displacer allows the working gas received when the pressure in the outer space of the displacer is higher to the expansion space. Because the pressure of the gas is discharged into the expansion space when the pressure becomes low, the momentum of the working gas blown out becomes strong, the working gas in the expansion space can be effectively stirred, and higher engine efficiency can be obtained. Can do.

  In the Stirling cycle apparatus having the above-described configuration, the regenerator may be disposed in the displacer, the regenerator being in communication with an expansion space facing one end of the displacer and a compression space facing the other end. The regenerator is divided into two, and a space in which one of the regenerators is stored is used as the pressure accumulation space.

  According to this configuration, heat exchange can be performed between the working gas taken into the pressure accumulating space and the regenerator, and the working gas can be ejected at a temperature close to that of the working gas in the expansion space.

  According to the present invention, in the Stirling cycle apparatus configured as described above, a first regenerator is disposed outside a cylinder housing the displacer, and the displacer has an expansion space facing one end of the displacer and the other. A second regenerator that communicates with the compression space facing the end is disposed, and a space in which the second regenerator is accommodated is defined as the pressure accumulation space.

  According to this configuration, heat exchange can be performed between the working gas taken into the pressure accumulating space and the regenerator, and the working gas can be ejected at a temperature close to that of the working gas in the expansion space.

  According to the present invention, in the Stirling cycle apparatus configured as described above, a one-way valve that prevents the working gas from flowing out of the pressure accumulating space is disposed at the working gas inlet.

  According to this configuration, it is possible to prevent the backflow of the working gas taken into the pressure accumulating space and prevent the pressure in the pressure accumulating space from decreasing before the working gas is ejected into the expansion space.

  Further, in the Stirling cycle device having the above-described configuration, the one-way valve that opens when the pressure difference between the pressure accumulation space and the expansion space becomes a predetermined value or more is disposed at the working gas outlet. It is characterized by that.

  According to this configuration, when the pressure in the expansion space is slightly lower than the pressure in the pressure accumulation space, the working gas is not discharged to the expansion space, but when the pressure difference between the pressure accumulation space and the expansion space exceeds a predetermined value. Since the directional valve is opened and the working gas is ejected, the momentum of the working gas to be ejected increases to increase the force for generating the jet flow, and higher engine efficiency can be obtained. Further, since the leakage of the working gas from the working gas outlet does not become a problem, the diameter of the working gas outlet can be increased, the jet flow rate can be increased, and the heat transfer rate can be greatly improved. Furthermore, it is possible to shift the jet timing by adjusting the one-way valve so as to generate the jet at a more effective timing.

  According to the present invention, the working gas taken into the displacer is not blown out immediately, but is taken into the pressure accumulation space in the displacer when the pressure in the outer space of the displacer is higher, and the working gas is taken up in the expansion space. Since the pressure is lower when the pressure becomes lower, the momentum of the working gas blown out is strengthened, the working gas in the expansion space is effectively disturbed, and the efficiency of the heat engine can be further enhanced. it can.

  1st Embodiment of this invention is described based on the figure from FIG. 1 to FIG. 1 is a sectional view of a Stirling cycle device, FIG. 2 is a partially enlarged sectional view of the Stirling cycle device, FIG. 3 is a partially enlarged sectional view of the Stirling cycle device, and is in a state different from FIG. FIG.

  A Stirling cycle apparatus 1 </ b> A shown in FIG. 1 has an α-type two-cylinder configuration and is used as a refrigerator, and includes a crank chamber 2, a first cylinder 3 and a second cylinder 4 protruding from the crank chamber 2. The first cylinder 3 and the second cylinder 4 are perpendicular to each other. A piston 5 is inserted into the first cylinder 3 to constitute a compressor. A displacer 6 is inserted into the second cylinder 4 to constitute an expander. The compression space 7 of the first cylinder 3 and the expansion space 8 of the second cylinder 4 are communicated by a working gas pipe 9. In the working gas line 9, a radiator 10 is provided near the first cylinder 3, and a regenerator 11 is provided near the second cylinder 4. The crank chamber 2 is provided with a crank disk 12 that is rotated by a power source (not shown) (not shown). The piston 5 is connected to the crank disk 12 via the connecting rod 13, and the displacer 4 is connected to the connecting rod 14. Are connected to each other.

  When the crank disk 12 rotates, the piston 5 reciprocates in the first cylinder 3 and the displacer 6 reciprocates in the second cylinder 4 with a predetermined phase difference. As a result, the working gas moves between the compression space 7 and the expansion space 8.

  The Stirling cycle apparatus 1A develops the operation according to the PV diagram of FIG. FIG. 4 shows a refrigeration cycle. In the compression process (1 → 2), the regenerator 11 and the expansion space 8 communicating with the compression space 7 are in high pressure. In the expansion process (3 → 4) from the isobaric process (2 → 3), the space communicating from the expansion space 8 becomes a low pressure, and the cycle is restarted through the isovolumetric process (4 → 1).

  The working gas in the compression space 7 whose pressure has increased in the compression process (1 → 2) and dissipated the heat in the radiator 10 transmits the heat to the regenerator 11 in the isovolumetric process (2 → 3), and then the expansion space 8 Head to. The working gas in the expansion space 8 becomes a low pressure in the expansion process (3 → 4), absorbs heat in the second cylinder 4, and cools the portion surrounding the expansion space 8. This portion of the second cylinder 4 functions as an endothermic head 4a, and the Stirling cycle device 1A serves as a refrigerator due to the cold heat of the endothermic head 4a. The working gas in the expansion space 8 is drawn back to the compression space 7 side in an isovolumetric process (4 → 1), and exchanges heat with the regenerator 11 in the process.

  Next, the pressure accumulation space of the displacer 6 that is the eye of the present invention will be described. Inside the displacer 6, a pressure accumulation space 15 is formed at an end portion facing the expansion space 8. In the pressure accumulating space 15, a working gas inflow port 16 composed of one through hole and a working gas jet port 17 composed of a plurality of small diameter through holes are formed facing the expansion space 8. A one-way valve 18 that prevents the working gas in the pressure accumulating space 15 from flowing out is disposed inside the working gas inlet 16. The one-way valve 18 is configured by fixing one end of a thin metal plate material (for example, phosphor bronze) to the inner wall of the pressure accumulating space 15 with a fastening member such as a screw or a rivet.

  FIG. 2 shows the behavior of the working gas during the compression process. In the compression process, the expansion space 8 becomes a high pressure. Since this pressure is higher than the pressure in the pressure accumulating space 15, the working gas flows into the pressure accumulating space 15 through the working gas inlet 16 by pushing the one-way valve 18 open. The working gas flows into the pressure accumulating space 15 from the working gas jet port 17 although it is a little. As described above, the pressure in the pressure accumulating space 15 also increases in accordance with the pressure increase in the expansion space 8 during the compression process.

  FIG. 3 shows the behavior of the working gas during the expansion process. In the expansion process, the expansion space 8 becomes a low pressure, and the pressure in the pressure accumulation space 15 becomes a high pressure. Since the working gas inlet 16 has a one-way valve 18, the working gas does not flow from here. Since the working gas jet port 17 has a small diameter, the flow resistance is large, and the working gas is not jetted through the working gas jet port 17 until the pressure difference between the expansion space 8 and the pressure accumulation space 15 reaches a certain level.

  When the pressure difference between the expansion space 8 and the pressure accumulation space 15 reaches a certain level, the working gas in the pressure accumulation space 15 is ejected from the working gas outlet 17. The ejection continues until the pressure difference between the expansion space 8 and the pressure accumulation space 15 becomes lower than the flow path resistance of the working gas ejection port 17. During ejection, the working gas forms a jet in the expansion space 8, equalizes the temperature of the working gas in the expansion space 8, and promotes heat transfer between the working gas and the heat absorbing head 4 a. Since heat exchange in the expansion process is thus promoted, the cold heat generated in the expansion space 8 can be efficiently taken out from the heat absorbing head 4a. The working gas received in the pressure accumulating space 15 when the pressure in the outer space of the displacer 6 is higher is blown out to the expansion space 8 when the pressure in the expansion space 8 becomes lower. The momentum of the working gas becomes strong, the working gas in the expansion space 8 can be effectively disturbed, and higher engine efficiency can be obtained.

  The first embodiment is an application example to a two-cylinder Stirling cycle apparatus called α-type, but a similar accumulator space has a single-cylinder Stirling cycle apparatus called β-type or a γ-type two-cylinder. It can also be provided in a Stirling cycle apparatus having a configuration. That is, the configuration of the first embodiment can be used regardless of the type of the Stirling cycle apparatus.

  A second embodiment of the present invention is shown in FIGS. FIG. 5 is a partially enlarged sectional view of the Stirling cycle apparatus, and FIG. 6 is a partially enlarged sectional view of the Stirling cycle apparatus, which is in a state different from FIG.

  In the second embodiment, the structure of the displacer is changed from the first embodiment. That is, the displacer 6 of the second embodiment has a pressure difference between the pressure accumulation space 15 and the expansion space 8 outside the working gas outlet 17 (the pressure accumulation space 15 has a higher pressure and the expansion space 8 has a lower pressure). A one-way valve 19 is disposed that opens when the pressure difference at the time exceeds a predetermined value. The one-way valve 19 has the same structure as the one-way valve 18, but the opening direction is different.

  Even if the expansion space 8 becomes low pressure during the expansion process, and the pressure in the pressure accumulation space 15 becomes high compared to that, the one-way valve 19 does not open until the pressure difference reaches a predetermined value. Only when the pressure difference reaches a predetermined value, the one-way valve 19 opens, and the working gas in the pressure accumulating space 15 is ejected from the working gas outlet 17, so that the force of the ejected working gas increases and the force for generating the jet is strong. Thus, higher engine efficiency can be obtained. Further, since leakage of the working gas from the working gas outlet 17 does not become a problem, the diameter of the working gas outlet 17 can be increased, the jet flow rate can be increased, and the heat transfer rate can be greatly improved. Furthermore, it is possible to shift the jet timing by adjusting the one-way valve 19 to generate the jet at a more effective timing. For example, it is possible to generate a jet only when the end surface of the displacer 6 moves away from the inner wall of the second cylinder 4.

  A third embodiment of the present invention is shown in FIG. FIG. 7 is a sectional view of the Stirling cycle apparatus.

  The Stirling cycle apparatus 1B of the third embodiment is different from the Stirling cycle apparatus 1A of the first embodiment in the following points. That is, a partition wall 20 is formed between the second cylinder 4 and the crank chamber 2, and a compression space 21 is formed between the partition wall 20 and the displacer 6. A rod 22 that penetrates the partition wall 20 and protrudes toward the crank chamber 2 is fixed to the displacer 6, and a connecting rod 14 is connected to the end of the rod 22. The working gas line 9 is connected to the compression space 21, and no regenerator is provided in the middle thereof. The regenerator is provided inside the displacer 6.

  The inside of the displacer 6 is divided into two concentric spaces by a cylindrical partition wall 23. The annular space outside the partition wall 23 becomes the main flow path 24, and the cylindrical space inside the partition wall 23 becomes the pressure accumulation space 25. The regenerator is also divided into two parts, one being a first regenerator 26 a inserted into the main flow path 24 and the other being a second regenerator 26 b inserted into the pressure accumulation space 25. In both the first regenerator 26 a and the second regenerator 26 b, one end communicates with the expansion space 8 and the other end communicates with the compression space 21. The flow path resistance of the pressure accumulating space 25 is much larger than that of the main flow path 24. Therefore, most of the working gas that moves between the compression space 21 and the expansion space 8 according to the operation of the displacer 6 flows through the main flow path 24. The main flow path 24 and the pressure accumulation space 25 are completely separated by the partition wall 23, and the working gas passing through the main flow path 24 and the pressure accumulation space 25 is not interchanged.

  A working gas inlet 27 and a one-way valve 28 are provided on the side of the pressure accumulating space 25 facing the compression space 21, and a working gas outlet 29 is provided on the side facing the expansion space 8. The structure of the working gas inlet 27, the one-way valve 28, and the working gas outlet 29 is the same as that of the working gas inlet 16, the one-way valve 18, and the working gas outlet 17 of the first embodiment.

  The space occupied by the compression space 7, the expansion space 8, the working gas conduit 9, the compression space 21, and the first regenerator 26a will be collectively referred to as “working space”. In the Stirling cycle apparatus 1B, the working spaces 7, 8, 9, 21, and 26a become high pressure during the compression process. Since this pressure is higher than the pressure in the pressure accumulating space 25, the working gas flows from the working gas inlet 27 into the pressure accumulating space 25 by pushing the one-way valve 28 open. When the expansion process is started, the working spaces 7, 8, 9, 21, 26a become low pressure, and the pressure in the pressure accumulating space 25 becomes high compared to that. Since the working gas ejection port 29 has a small diameter, the flow resistance is large, and the working gas is not ejected through the working gas ejection port 29 until the pressure difference between the expansion space 8 and the pressure accumulation space 25 reaches a certain level.

  When the pressure difference between the expansion space 8 and the pressure accumulation space 25 reaches a certain level, the working gas in the pressure accumulation space 25 is ejected from the working gas outlet 29. The ejection continues until the pressure difference between the expansion space 8 and the pressure accumulation space 25 becomes lower than the flow path resistance of the working gas ejection port 29. During ejection, the working gas forms a jet in the expansion space 8, equalizes the temperature of the working gas in the expansion space 8, and promotes heat transfer between the working gas and the heat absorbing head 4 a. Since heat exchange in the expansion process is thus promoted, the cold heat generated in the expansion space 8 can be efficiently taken out from the heat absorbing head 4a.

  The working gas received in the pressure accumulating space 25 when the pressure in the compression space 21 is higher is ejected into the expansion space 8 when the pressure in the expansion space 8 becomes lower. Becomes stronger, the working gas in the expansion space 8 can be effectively disturbed, and higher engine efficiency can be obtained. Further, since the second regenerator 26b is also present in the pressure accumulating space 25, heat is exchanged between the working gas flowing in from the working gas inlet 27 and the second regenerator 26b, and the working gas is used as the working gas in the expansion space 8. Since it can be ejected at a temperature close to, there is little heat loss.

  The configuration of the third embodiment can also be applied to a Stirling cycle apparatus having a structure other than the structure of FIG. Further, when the one-way valve 19 of the second embodiment is combined with the working gas outlet 29 of the third embodiment, the momentum of the working gas ejected further increases, and higher efficiency can be obtained.

  A fourth embodiment of the present invention is shown in FIG. FIG. 8 is a sectional view of the Stirling cycle apparatus.

  The Stirling cycle apparatus 1C has a β-type cylinder configuration and is used as a refrigerator. The Stirling cycle device 1C is a free piston type, and the cylinders 30 and 31 form the center of assembly. The axes of the cylinders 30 and 31 are aligned on the same straight line. A piston 32 is inserted into the cylinder 30, and a displacer 33 is inserted into the cylinder 31. The piston 32 and the displacer 33 reciprocate without contacting the inner walls of the cylinders 30 and 31 by the mechanism of the gas bearing during the operation of the Stirling cycle apparatus 1C. The piston 32 and the displacer 33 move with a predetermined phase difference.

  A cup-shaped magnet holder 34 is provided at one end of the piston 32. A displacer shaft 35 protrudes from one end of the displacer 33. The displacer shaft 35 penetrates the piston 32 and the magnet holder 34 so as to be slidable in the axial direction, and protrudes into the back pressure space.

  The cylinder 30 holds the linear motor 40 outside the portion corresponding to the operation area of the piston 32. The linear motor 40 includes an outer yoke 42 provided with a coil 41, an inner yoke 43 provided so as to be in contact with the outer peripheral surface of the cylinder 30, and a ring shape inserted into an annular space between the outer yoke 42 and the inner yoke 43. Magnet 44, a tubular body 45 surrounding the outer yoke 42, an outer yoke 42, an inner yoke 43, and synthetic resin end brackets 46, 47 for holding the tubular body 45 in a predetermined positional relationship. The magnet 44 is fixed to the magnet holder 34.

  The central portion of the spring 50 is fixed to the hub portion of the magnet holder 34. The center portion of the spring 51 is fixed to the displacer shaft 35. The outer peripheral portions of the springs 50 and 51 are fixed to the end bracket 47. A spacer 52 is disposed between the outer peripheries of the springs 50 and 51, whereby the springs 50 and 51 maintain a certain distance. The springs 50 and 51 are obtained by making a spiral cut into a disk-shaped material, and have the role of causing the displacer 33 to resonate with a predetermined phase difference (65 ° to 90 ° phase difference) with respect to the piston 32. Fulfill.

  A high temperature side heat transfer head 60 and a low temperature side heat transfer head 61 are disposed outside the portion of the cylinder 31 corresponding to the operating region of the displacer 33. The high temperature side heat transfer head 60, the low temperature side heat transfer head 61, and the regenerator tube 68 described later constitute a part of the outer shell of the Stirling cycle apparatus 1C.

  The high temperature side heat transfer head 60 has a ring shape, and the low temperature side heat transfer head 61 has a cap shape, both of which are made of metal having good heat conductivity such as copper or copper alloy. A ring-shaped high-temperature side internal heat exchanger 62 is mounted on the inner peripheral surface of the high-temperature side heat transfer head 60, and a ring-shaped low-temperature-side internal heat exchanger 63 is also mounted on the inner peripheral surface of the low-temperature side heat transfer head 61. Installed. Each of the high temperature side internal heat exchanger 62 and the low temperature side internal heat exchanger 63 has air permeability, and transfers the heat of the working gas passing through the inside to the high temperature side heat transfer head 60 and the low temperature side heat transfer head 61. The high temperature side internal heat exchanger 62 and the low temperature side internal heat exchanger 63 are formed by corrugating a thin plate made of copper or copper alloy into a ring shape.

  The high temperature side heat transfer head 60 and the low temperature side heat transfer head 61 are thus supported outside the cylinder 31 with the high temperature side internal heat exchanger 62 and the low temperature side internal heat exchanger 63 interposed therebetween. The cylinder 30 and the pressure vessel 70 are connected to the high temperature side heat transfer head 60. The pressure vessel 70 encloses the linear motor 40, the cylinder 30, and the piston 32. A space on the outer peripheral side of the cylinder 30 inside the pressure vessel 70 becomes a back pressure space 71.

  An annular space surrounded by the high temperature side heat transfer head 60, the cylinders 30 and 31, the piston 32, the displacer 33, the displacer shaft 35, and the high temperature side internal heat exchanger 62 is a compression space 65. A space surrounded by the low temperature side heat transfer head 61, the cylinder 31, the displacer 33, and the low temperature side internal heat exchanger 63 becomes an expansion space 66.

  A first regenerator 67 is disposed between the high temperature side internal heat exchanger 62 and the low temperature side internal heat exchanger 63 outside the cylinder 31 that houses the displacer 33. The first regenerator 67 is formed by winding a resin film into a cylindrical shape, and a plurality of minute protrusions are scattered on one side of the film to form gaps corresponding to the height of the protrusions between the films. It is a street. A regenerator tube 68 wraps the outside of the first regenerator 67 and forms an airtight passage between the heat transfer heads 60 and 61. The regenerator tube 68 can be formed of stainless steel, for example. Both ends of the regenerator tube 68 are connected to the inner surfaces of the high temperature side heat transfer head 60 and the low temperature side heat transfer head 61, and the high temperature side heat transfer head 60 and the low temperature side heat transfer head 61 are connected by the regenerator tube 68.

  The inside of the displacer 33 becomes a pressure accumulation space 80, and the second regenerator 81 is accommodated therein. The structure of the second regenerator 81 is the same as that of the first regenerator 67. One end of the second regenerator 81 communicates with the expansion space 66, and the other end communicates with the compression space 65. A working gas inlet 82 and a one-way valve 83 are provided on the side of the pressure accumulating space 80 facing the compression space 65, and a working gas outlet 84 is provided on the side facing the expansion space 66. The structure of the working gas inlet 82, the one-way valve 83, and the working gas jet 84 is the same as that of the working gas inlet 16, the one-way valve 18, and the working gas jet 17 of the first embodiment. Similarly to the case of the first embodiment, the space occupied by the high temperature side heat exchanger 62, the space occupied by the low temperature side heat exchanger 63, the compression space 65, the expansion space 66, and the space occupied by the first regenerator 67. Are collectively referred to as “operating space”.

  The Stirling cycle apparatus 1C operates as follows. When an alternating current is supplied to the coil 41 of the linear motor 40, an alternating magnetic field penetrating the magnet 44 is generated between the inner yoke 43 and the outer yoke 42, and the magnet 44 reciprocates by receiving an electromagnetic force in the axial direction. The piston system is made smooth by supplying electric power having a frequency substantially equal to the resonance frequency determined by the total mass of the piston system (piston 32, magnet holder 34, magnet 44, and spring 50) and the spring constant of the spring 50. Start a sinusoidal reciprocating motion.

  In the displacer system (the displacer 33, the displacer shaft 35, and the spring 51), the resonance frequency determined by the total mass and the spring constant of the spring 51 is set to resonate with the drive frequency of the piston 32.

  Due to the reciprocating motion of the piston 32, the working spaces 62, 63, 65, 66 and 67 cause pressure changes such as compression and expansion. The displacer 33 also reciprocates in synchronization with the drive frequency of the piston 32 by the thrust resulting from this pressure change. At this time, a predetermined phase difference determined by the difference between the driving frequency of the piston 32 and the resonance frequency of the displacer system occurs between the reciprocating motion of the displacer 33 and the reciprocating motion of the piston 32.

  Due to the movement of the displacer 33, a reverse Stirling cycle is formed between the compression space 65 and the expansion space 66.

  When the working gas that moves between the compression space 65 and the expansion space 66 during operation passes through the high temperature side internal heat exchanger 62 and the low temperature side internal heat exchanger 63, the working gas transfers its heat to the high temperature side internal heat exchanger. The heat is transferred to the high temperature side heat transfer head 60 and the low temperature side heat transfer head 61 through 62 and the low temperature side internal heat exchanger 63. Since the working gas from the compression space 65 toward the expansion space 66 is high temperature, the high temperature side heat transfer head 60 is heated, and the high temperature side heat transfer head 60 becomes a heat dissipation head. Since the working gas from the expansion space 66 toward the compression space 65 is at a low temperature, the low temperature side heat transfer head 61 is cooled, and the low temperature side heat transfer head 61 becomes a heat absorption head. By radiating heat with the high temperature side heat transfer head 60 and absorbing heat with the low temperature side heat transfer head 61, the Stirling cycle apparatus 1C functions as a refrigeration engine.

  The first regenerator 67 and the second regenerator 81 function to pass the working gas so that sensible heat due to the working gas temperature in the compression space 65 and the expansion space 66 is not transmitted to the counterpart space. The second regenerator 81 has a larger flow path resistance than the first regenerator 67, so that most of the working gas passes through the first regenerator 67.

  The hot working gas that has entered the first regenerator 67 from the compression space 65 through the high temperature side internal heat exchanger 62 gives its sensible heat to the first regenerator 67 when passing through the first regenerator 67, Flows into the expansion space 66 through the low-temperature side internal heat exchanger 63 in a state where the temperature has decreased. The hot working gas that has entered the second regenerator 81 from the compression space 65 also gives sensible heat to the second regenerator 81 when passing through the second regenerator 81, and enters the expansion space 66 in a state where the temperature has decreased. Inflow. The low-temperature working gas that has entered the first regenerator 67 after cooling the low temperature side internal heat exchanger 63 from the expansion space 66 recovers sensible heat from the first regenerator 67 when passing through the first regenerator 67. In the state where the temperature has risen, it flows into the compression space 65 through the high temperature side heat exchanger 62. The low-temperature working gas that has entered the second regenerator 81 from the expansion space 66 also recovers sensible heat from the second regenerator 81 when passing through the second regenerator 81.

  In the Stirling cycle apparatus 1C, in the compression process, all the spaces of the compression space 65, the regenerator 67, the expansion space 66, and the high temperature side and low temperature side internal heat exchangers 62 and 63 become high pressure. Since this pressure is higher than the pressure in the pressure accumulating space 80, the working gas flows from the working gas inlet 82 into the pressure accumulating space 80 by pushing the one-way valve 83 open. When the expansion process is started, all of the compression space 65, the regenerator 67, the expansion space 66, the high temperature side and low temperature side internal heat exchangers 62 and 63 become low pressure, and the pressure in the pressure accumulation space 80 becomes high compared to it. . Since the working gas ejection port 84 has a small diameter, the flow resistance is large, and the working gas is not ejected through the working gas ejection port 84 until the pressure difference between the expansion space 66 and the pressure accumulation space 80 reaches a certain level.

  When the pressure difference between the expansion space 66 and the pressure accumulation space 80 reaches a certain level, the working gas in the pressure accumulation space 80 is ejected from the working gas outlet 84. The ejection continues until the pressure difference between the expansion space 66 and the pressure accumulation space 80 becomes lower than the flow path resistance of the working gas ejection port 84. During ejection, the working gas forms a jet in the expansion space 66, equalizes the temperature of the working gas in the expansion space 66, and promotes heat transfer between the working gas and the low-temperature side heat transfer head 61. Since heat exchange in the expansion process is thus promoted, the cold generated in the expansion space 66 can be efficiently taken out from the low temperature side heat transfer head 61.

  The working gas received in the pressure accumulating space 80 when the pressure in the compression space 65 is higher is ejected into the expansion space 66 when the pressure in the expansion space 66 becomes lower. The working gas in the expansion space 66 can be effectively disturbed, and higher engine efficiency can be obtained. Further, heat exchange can be performed between the working gas taken into the pressure accumulating space 80 and the second regenerator 81, and the working gas can be ejected at a temperature close to that of the working gas in the expansion space 66, so that heat loss can be reduced. If the one-way valve 19 of the second embodiment is combined with the working gas outlet 84, the momentum of the working gas to be ejected is further increased, and higher efficiency can be obtained.

[Example]
It was theoretically examined how much the performance could be improved by implementing the present invention. In the examination, assuming a Stirling cycle apparatus having a β-type single cylinder configuration as shown in FIG. 8, the flow velocity when the working gas was ejected from the working gas ejection port was obtained using a general fluid analysis program. The environmental condition assumed that the pressure difference between the pressure accumulation space and the expansion space was 0.2 MPa. The number of working gas ejection ports is 57, and it is assumed that they are arranged in the pattern shown in FIG. The diameter D of the working gas outlet was 0.5 mm, and the interval r between the working gas outlets was 5 mm.

  The analysis screen is shown in FIG. From this screen, it was found that the working gas was ejected into the expansion space and reached the vicinity of the endothermic surface at a flow velocity of 50 m / s or more. It was also found that the jetted working gas was disturbing the working gas in the expansion space.

Next, the heat transfer promotion effect by the working gas jet is calculated. Using the empirical formula proposed by Martin (reference: Martin, H., Advances in Heat Transfer, 13 (1977), 1: From the Japan Society of Mechanical Engineers, "Revised Heat Transfer Engineering", 4th edition, page 66) To calculate the heat transfer coefficient. The empirical formula used for the gas outlet in FIG. 9 is as follows.
F = 0.5Re ^2/3 (2000 <Re <100,000) (Formula 5)
0.004 ≦ g <0.04 (Formula 6)
2 <H / D / 12 (Formula 7)
H: Distance between working gas outlet and endothermic surface D: Diameter of working gas outlet Nu: Nusselt number

The relationship between the Nusselt number Nu and the heat transfer coefficient h and the equation for obtaining the Reynolds number Re are shown below.
λ: Thermal conductivity of fluid (W / mK)
u: Flow velocity (m / S)
ν: Kinematic viscosity coefficient (m ² / s)

The calculation conditions were set as follows. Working gas outlet diameter D = 0.5 mm, distance r between working gas outlets r = 5 mm, distance H = 5 mm between working gas outlet and endothermic surface, jet velocity from working gas outlet is the analysis result of FIG. Was assumed to be u = 50 m / s. As the working gas, ν = 3.665 × 10 ⁻⁶ (m ² / s) and λ = 0.153 (W / mK) were used as helium. When these values are substituted into the above equation, the heat transfer coefficient is h = 5505 (W / m ² K).

Next, the heat transfer coefficient is calculated on the assumption that the displacer without the working gas jet outlet moves the working gas at the end face on the expansion space side. If the speed at which the displacer moves and the speed at which the working gas moves are the same, the maximum speed of the working gas matches the maximum speed of the displacer. The equation for calculating the working gas velocity with the displacer amplitude as Xd and the operating frequency as f is u = Xd · ω = Xd · 2πf (Equation 10)
It becomes. The equation for obtaining the heat transfer of an orthogonal flat plate is Nu = 0.060 Re ^1/2 (Equation 11) from the reference document (The Japan Society of Mechanical Engineers, “Heat Transfer Engineering Data” Rev. 4th Edition, page 62)
Was used. The heat transfer coefficient h = 2 when calculating the diameter of the displacer end face and the endothermic surface as a representative length of 40 mm, the displacer stroke (amplitude) Xd = 4 mm, and the operating frequency 60 Hz.
94 (W / m ² K). As the working gas, ν = 3.665 × 10 ⁻⁶ (m ² / s) and λ = 0.153 (W / mK) were used as the working gas as described above.

  The above calculation result shows the possibility that the heat transfer coefficient can be increased by 10 times or more by providing the working gas jet port, and it can be seen that the jet effect of the working gas is very high.

Next, as in the fourth embodiment of FIG. 8, the effect of inserting the second regenerator inside the displacer was verified by experiments. As shown in FIG. 8, a one-way valve is attached so that the working gas flows in from the compression space side of the displacer, and a working gas outlet is provided so that the working gas is ejected from the expansion space side of the displacer (“with regenerator” ") Stirling cycle equipment was prepared. One working gas outlet has a diameter of 0.5 mm. As the second regenerator, an open cell foam of polyester urethane foam was used. For comparison, a Stirling cycle device having a structure in which the working gas outlet and the second regenerator are not provided in the displacer (“no regenerator”) was also prepared.

Both the “with regenerator” Stirling cycle device and the “without regenerator” Stirling cycle device use helium as the working gas, the displacer diameter is 39.8 mm, the piston stroke is 4 mm, the operating frequency is 70 Hz, The internal pressure was 3.4 MPa.
The outer diameter x inner diameter x length of the regenerator (first regenerator) was 68 mm x 54 mm x 55 mm. In the structure of the present invention, the outer diameter x length of the second regenerator inserted into the displacer is 34.5 mm x 52.5.
mm.

  In the experiment, both the Stirling cycle device with “regenerator” and the Stirling cycle device without “regenerator” were adjusted so that the temperature of the radiator was constant at 30 ° C. and the temperature of the endothermic head at −23 ° C. The piston amplitude was also controlled to be constant. The result is shown in FIG. The ratio COP indicates that the COP of “without regenerator” is 1, and how many times the COP of “with regenerator” is increased. From FIG. 11, it can be seen that the COP is 1.2 times or more in the case of “with regenerator” compared to the case of “without regenerator”.

Next, the effect of the working gas jet was verified experimentally. In the experiment, a Stirling cycle apparatus having a β-type single cylinder structure was used in the same manner as the Stirling cycle apparatus used in the comparative experiment of “with regenerator” and “without regenerator”. The Stirling cycle device with “jet” has a structure in which a one-way valve is attached so that the working gas flows in from the compression space side of the displacer, and a working gas outlet is provided so that the working gas is ejected from the expansion space side of the displacer And no regenerator is inserted in the displacer. There were three working gas jets with a diameter of 0.1 mm. The “no jet” Stirling cycle apparatus has the same structure as the “with jet” Stirling cycle apparatus except that there is no working gas outlet. The specifications of the Stirling cycle apparatus were the same as the Stirling cycle apparatus used in the comparative experiment of “with regenerator” and “without regenerator”.

  In the experiment, both the Stirling cycle device with “jet” and the Stirling cycle device without “jet” were adjusted so that the temperature of the radiator was constant at 30 ° C. and the temperature of the endothermic head was −23 ° C. The piston amplitude was also controlled to be constant. The result is shown in FIG. The specific COP indicates a COP of “no jet” as 1, and indicates how many times the COP of “with jet” is increased. From FIG. 12, it can be seen that the COP is improved in the case of “with jet” compared to the case of “without jet”.

  Each embodiment of the present invention has been described above, but various modifications can be made without departing from the spirit of the present invention.

  The application object of the present invention is not limited to the refrigerator. A similar effect can be obtained by applying the present invention to a Stirling cycle power engine and generating a jet on the heat absorption side.

  The present invention can be used for all Stirling cycle apparatuses.

Cross section of Stirling cycle equipment Partial enlarged sectional view of Stirling cycle equipment A partially enlarged sectional view of the Stirling cycle device in a state different from FIG. PV diagram Partial enlarged sectional view of the Stirling cycle apparatus according to the second embodiment A partially enlarged cross-sectional view of the Stirling cycle apparatus according to the second embodiment, in a state different from FIG. Sectional drawing of the Stirling cycle apparatus which concerns on 3rd Embodiment Sectional drawing of the Stirling cycle apparatus which concerns on 4th Embodiment The figure which shows the arrangement pattern of the working gas outlet in the analysis experiment Analysis screen of flow velocity when working gas is ejected from working gas outlet Graph showing ratio COP value based on presence or absence of regenerator A graph showing the ratio COP value based on the presence or absence of a jet

Explanation of symbols

1A, 1B, 1C Stirling cycle device 2 Crank chamber 3 1st cylinder 4 2nd cylinder 5 Piston 6 Displacer 7 Compression space 8 Expansion space 9 Working gas line 10 Radiator 11 Regenerator 15 Accumulated space 16 Working gas inlet 17 Actuation Gas outlet 18 One-way valve 19 One-way valve 21 Compression space 25 Accumulated space 26a First regenerator 26b Second regenerator 27 Working gas inlet 28 One-way valve 29 Working gas outlet 31 Cylinder 33 Displacer 65 Compression space 66 Expansion Space 67 First regenerator 80 Accumulated space 81 Second regenerator 82 Working gas inlet 83 One-way valve 84 Working gas jet

Claims (5)

The piston and displacer are reciprocated in the cylinder with a phase difference by the power source, and the working gas flows and compresses and expands through the regenerator, thereby generating the working gas in the expansion space facing one end of the displacer. In the Stirling cycle device that absorbs heat,
When the pressure in the outer space of the displacer is higher in the displacer, the working gas is received through the working gas inlet, and when the pressure is lower in the expansion space, the working space is operated through the working gas outlet. A Stirling cycle apparatus characterized in that a pressure accumulation space for ejecting gas is formed. A regenerator that communicates with an expansion space facing one end of the displacer and a compression space facing the other end is disposed inside the displacer, and the regenerator is divided into two, and a space in which one of the regenerators is stored. The Stirling cycle device according to claim 1, wherein the pressure accumulation space is used. A first regenerator is disposed outside a cylinder containing the displacer, and a second regeneration unit communicates with an expansion space facing one end of the displacer and a compression space facing the other end inside the displacer. The Stirling cycle device according to claim 1, wherein a space in which the second regenerator is housed is used as the pressure accumulation space. The Stirling cycle device according to any one of claims 1 to 3, wherein a one-way valve that prevents the working gas from flowing out of the pressure accumulating space is disposed at the working gas inlet. The one-way valve which opens when the pressure difference of the said pressure accumulation space and the said expansion | swelling space becomes more than a predetermined value is arrange | positioned at the said working gas jet nozzle. The Stirling cycle apparatus according to Item 1.