HEAT TRANSPORTING APPARATUS
In a heat transporting apparatus, a cylinder is filled with a refrigerant and pistons are arranged in the cylinder, which compress and expand the refrigerant in the cylinder. A magnet unit is movably provided around the cylinder to apply a magnetic field to the cylinder, which is alternately increased and decreased in accordance with a movement of the magnet unit. A thermal accumulator is received in the cylinder, which produces heat depending on one of the increasing and decreasing of the magnetic field at the compression of the refrigerant, and absorbs heat depending on the other of the increasing and decreasing of the magnetic field at the expansion of the refrigerant. Heat exchangers are located in the cylinder, which radiates the heat from the refrigerant and thermal accumulator to an exterior of the apparatus, and absorbs external heat and transfers the heat to the refrigerant and thermal accumulator.
This application is based upon and claims the benefit of priority from prior Japanese Patent Application No. 2005-352242, filed Dec. 6, 2005, the entire contents of which are incorporated herein by reference.
BACKGROUND OF THE INVENTION1. Field of the Invention
The present invention relates to a heat transporting apparatus for transporting heat with utilizing a refrigerating cycle having a refrigerant compressing and expanding processes.
2. Description of the Related Art
Refrigerators or heat pumps have been known as apparatuses that utilize a refrigerating cycle to transport heat. Among the refrigerators serving as heat transporting apparatuses, Stirling refrigerators are gathering much attention for their high energy efficiency. The Stirling refrigerator is essentially expected to offer a very high refrigerating efficiency. However, the Stirling refrigerator is actually used mainly to provide very low temperatures (which are almost equal to liquid helium temperature). On the other hand, the Stirling refrigerator can use helium as a refrigerant; helium is a natural refrigerant which is harmless to human beings and which is not involved in ozone layer destruction or global warming.
The Stirling refrigerator operates in accordance with a Stirling refrigerating cycle including four basic processes, isothermal compression, isovolumetric cooling, isothermal expansion, and isovolumetric heating. To implement the Stirling refrigerating cycle, a high- and low-temperature cylinder sections are provided in which a refrigerant is sealed. A higher-temperature heat exchanger, a thermal accumulator or heat storage device, and a lower-temperature heat exchanger are disposed between the cylinder sections. Compression and expansion of the refrigerant are repeated in the cylinder sections to transport heat from the lower-temperature heat exchanger to the higher-temperature heat exchanger. Of the four basic processes of the Stirling refrigerating cycle, the isovolumetric heating and cooling are mainly based on the heat exchange between the heat exchanger and the thermal accumulator. The heat radiation and absorption by the higher- and lower-temperature heat exchangers occur during the isothermal compression and expansion processes.
However, the efficiency of the Stirling refrigerating cycle used for the Stirling refrigerator is mainly limited by the heat conducting performance of the higher- and lower-temperature heat exchangers and thermal accumulator. Consequently, in spite of the theoretical high efficiency, actual apparatuses are disadvantageously inefficient and fail to achieve the desired performance.
Thus, to improve the performance of the refrigerator, it is important to increase the heat exchanging efficiency during the Stirling refrigerating cycle. To increase the heat exchanging efficiency, it is necessary to improve the heat exchanging performance of the higher- and lower-temperature heat exchangers and thermal accumulator.
BRIEF SUMMARY OF THE INVENTIONAccording to an aspect of the present invention, there is provided a heat transfer apparatus comprising:
a container filled with a refrigerant;
an operation unit which compresses the refrigerant to produce heat and expands the refrigerant to absorb heat in the container, alternately;
a generating unit configured to generate a magnetic field which is increased and decreased, alternately;
a thermal accumulator received in the container, to which the magnetic field is applied, and which produces heat depending on one of the increasing and decreasing of the magnetic field at the time of compression of the refrigerant and absorbs heat depending on the other of the increasing and decreasing of the magnetic field at the time of expansion of the refrigerant; and
first and second heat transfer units, the first heat transfer unit transferring the heat produced in the refrigerant and the thermal accumulator to the outside of the apparatus, and the second heat transfer unit transferring external heat to the refrigerant and the thermal accumulator.
According to another aspect of the present invention, there is provided a heat transporting apparatus comprising:
a cylindrical container provided with compression and expansion chambers communicating with each other and filled with a refrigerant;
a compression piston received in the cylindrical container, which compresses the refrigerant in the expansion chamber and an expansion piston which expands the refrigerant in the expansion chamber;
a generating unit configured to generate a magnetic field which is increased and decreased, alternately;
a thermal accumulator received in the cylindrical container, to which the magnetic field is applied, and which produces heat depending on one of the increasing and decreasing of the magnetic field at the time of compression of the refrigerant, and absorbs heat depending on the other of the increasing and decreasing of the magnetic field at the time of expansion of the refrigerant; and
first and second heat transfer units, the first heat transfer unit transferring the heat produced in the refrigerant and the thermal accumulator to the outside of the apparatus, and the second heat transfer unit transferring external heat to the refrigerant and the thermal accumulator.
According to yet another aspect of the present invention, there is provided a heat transporting apparatus comprising:
a cylindrical container filled with a refrigerant;
pistons received in the cylindrical container, which compress and expand the refrigerant;
a generating unit configured to generate a magnetic field which is increased and decreased, alternately;
a thermal accumulator received in the cylindrical container, to which the magnetic field is applied, and which produces heat depending on one of the increasing and decreasing of the magnetic field at the time of compression of the refrigerant and absorbs heat depending on the other of the increasing and decreasing of the magnetic field at the time of expansion of the refrigerant; and
first and second heat transfer units, the first heat transfer unit transferring the heat produced in the refrigerant and the thermal accumulator to the outside of the apparatus, and the second heat transfer unit transferring external heat to the refrigerant and the thermal accumulator.
BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWING
With reference to the drawings, description will be given of heat transporting apparatuses according to embodiments of the present invention.
FIRST EMBODIMENT
In
Inside the cylinder 1, a higher-temperature heat exchanger 4 is placed in proximity to one end of the heat storage device 2. A lower-temperature heat exchanger 5 is placed in proximity to the other end of the heat storage device 2. The higher-temperature heat exchanger 4 radiates heat from the refrigerant and heat storage device 2 to the exterior of the apparatus. The lower-temperature heat exchanger 5 absorbs external heat on the basis of heat absorption by the refrigerant and heat storage device 2.
A compression piston 6 is provided in an opening of the cylinder 1 which is closer to the higher-temperature heat exchanger 4. An expansion piston 7 is provided in an opening of the cylinder 1 which is closer to the lower-temperature heat exchanger 5. The compression piston 6 and expansion piston 7 constitute an operation unit. The compression piston 6 moves in the direction of arrow A shown in
A mechanism 8 for generating a magnetic field and increasing and reducing the magnetic field is placed outside the cylinder 1 around the periphery of the heat storage device 2. The magnetic field increasing and reducing mechanism 8 increases and reduces the magnitude of a magnetic field that is applied to the magnetic material 3 in the heat storage device 2. The magnetic field increasing and reducing mechanism 8 is not limited to a particular one shown in
Now, description will be given of the operation of the refrigerator configured as described above.
First, the compression piston 6 is moved in a direction A, that is, from the left to right of the figure, to compress the refrigerant in the cylinder 1 as shown in
Then, as shown in
Then, as shown in
Then, as shown in
The process shown in
Accordingly, in the refrigerating cycle having the refrigerant compression and expansion processes, the compression process not only allows the refrigerant to generate heat but also applies a magnetic field to the magnetic material 3 constituting the heat storage device 2 to allow the magnetic material 3 to make a heat generating reaction. The heat from the magnetic material 3 is radiated via the higher-temperature heat exchanger 4. Consequently, this refrigerator can radiate more heat to the exterior of the apparatus. The expansion process not only expands the refrigerant to allow it to absorb heat but also removes the magnetic field to allow the magnetic material 3 to make a heat absorbing reaction. This enables more external heat to be absorbed via the lower-temperature heat exchanger 5. Thus, simultaneously with the heat generation and absorption by the refrigerant, the heat storage device 2 composed of the magnetic material 3 is caused to make heat generating and absorbing reactions. The present refrigerating cycle having the compression and expansion processes offers a drastically increased heat exchanging efficiency. Therefore, a Stirling refrigerating cycle with a good heat transporting capability can be implemented.
The above first embodiment repeats the four basic processes, isothermal compression, isovolumetric cooling, isothermal expansion, and isovolumetric heating, to implement a Stirling refrigerating cycle. An Ericsson cycle can be implemented by substituting isobaric processes for the two isovolumetric processes in the Stirling refrigerating cycle. A Brayton cycle can be implemented by substituting adiabatic processes for the compression and expansion processes in the Stirling refrigerating cycle and substituting isobaric processes for the two isovolumetric processes.
SECOND EMBODIMENT
In
A heat storage device 15 is placed in the compression cylinder 12. The heat storage device 15 is provided with a magnetic material 16 having its temperature changed in response to an increase or decrease in the magnitude of a magnetic field. In this embodiment, the magnetic material 16 is a positive one, for example, a GD-based material, which has its temperature raised (heat generation) in response to an increase in the magnitude of the magnetic field, while having its temperature lowered (heat absorption) in response to a decrease in the magnitude of the magnetic field. As the magnetic material 16, generally spherical magnetic materials 16a of diameter about 1 mm or less may be filled in to the heat storage device 15 to form a porous member containing a large number of voids as shown in
A higher-temperature heat exchanger 17 is placed in proximity to the heat storage device 15. The higher-temperature heat exchanger 17 is placed opposite the communication pipe 14 across the heat storage device 15. The higher-temperature heat exchanger 17 radiates heat from the refrigerant and heat storage device 15 to the exterior of the apparatus.
A compression piston 18 is provided in the compression cylinder 12. The compression piston 18 is inserted into the compression cylinder 12 through its opening to compress the refrigerant in the compression cylinder 12. A piston shaft 19 is connected to the compression piston 18. A connecting bar 20 is connected to the piston shaft 19 and to a flywheel 21 at a position away from its rotating center. The connecting bar 20 thus constitutes a crank mechanism that converts a rotating motion of the flywheel 21 into a reciprocating motion to reciprocate the piston shaft 19 in the direction of arrow E in
A lower-temperature heat exchanger 23 is placed inside the expansion cylinder 13. The lower-temperature heat exchanger 23 absorbs external heat on the basis of heat absorption by the refrigerant and heat storage device 15. An expansion piston 24 is provided in the expansion cylinder 13. The expansion piston 24 is inserted into the expansion cylinder 13 through its opening to compress the refrigerant in the expansion cylinder 13. A piston shaft 25 is connected to the expansion piston 24. A connecting bar 26 is connected to the piston shaft 25 and to a flywheel 27 at a position away from its rotating center. The connecting bar 26 thus constitutes a crank mechanism that converts a rotating motion of the flywheel 27 into a reciprocating motion to reciprocate the piston shaft 25 in the direction of arrow F in
A disk-like support plate 28 is integrally provided on the piston shaft 19. A mechanism 30 for generating a magnetic field and increasing and reducing the magnetic field is provided on the support plate 28 via a support arm 29. The magnetic field increasing and reducing mechanism 30 has a cylindrical shape with the compression cylinder located in its hollow portion. The piston shaft 19 reciprocates in the direction of arrow E to allow the magnetic field increasing and reducing mechanism 30 to increase or reduce the magnitude of a magnetic field that is applied to the heat storage device 15.
In the refrigerator shown in
The magnetic field increasing and reducing mechanism 30 may be, for example, a double cylindrical magnet called a Halbach magnet, such as the one shown in
Further, a weak magnetic field can be generated in the hollow portion of the inner cylindrical magnet 301 by making the direction of the magnetic field 305 generated in the hollow portion by the inner cylindrical magnet 301, opposite to the direction of the magnetic field 306 generated in the hollow portion by the outer cylindrical magnet 302 so that the magnetic fields 305 and 306 cancel each other, as shown in
A cylinder main body 31 shown in
In this refrigerator, first, as shown in
Then, as shown in
Then, as shown in
Then, as shown in
The process shown in
Therefore, the above embodiment can produce effects similar to those of the first embodiment. Moreover, the compression piston 18, expansion piston 24, and magnetic field increasing and reducing mechanism 30 perform the series of operations using the driving motor 22 as a driving source. This enables the Stirling refrigerating cycle to be executed both automatically and stably. Furthermore, the rotation speed of the driving motor can be increased to achieve high-speed refrigeration.
The magnetic material 16 constituting the heat storage device 15 is a porous member containing a large number of voids or a bulk material containing communication holes which consist of small holes and which communicate with the exterior. The refrigerant can thus pass through the interior of the magnetic material 16. This makes it possible to increase the contact area between the magnetic material 16 and the refrigerant as well as the rate of heat transfer between the magnetic material 16 and the refrigerant. The magnetic material 16 and the refrigerant can thus efficiently exchange heat with each other to further improve the heat generating and absorbing effects of the heat storage device 15.
Moreover, a strong magnetic field required to operate the magnetic material 16 can be easily obtained by using a cylindrical magnet called a Halbach magnet as the magnetic field increasing and reducing mechanism 30 and composed of the outer cylindrical magnet 302 and the inner cylindrical magnet 301, located in the hollow portion.
THIRD EMBODIMENT
In the refrigerator shown in
The cool storage section 32 includes a heat storage device 321 composed of a positive magnetic material 331 which has its temperature raised in response to an increase in the magnitude of the magnetic field and which has its temperature lowered in response to a decrease in the magnitude of the magnetic field, and a storage device 322 composed of a negative magnetic material 332 which has its temperature lowered in response to an increase in the magnitude of the magnetic field and which has its temperature raised in response to a decrease in the magnitude of the magnetic field. The positive magnetic material 331 is what is called a ferromagnetic substance or a meta-magnetic substance which is in a paramagnetic state (magnetic spins are disordered) with no magnetic field applied to the material and which is brought to a ferromagnetic state (magnetic spins are ordered) when a magnetic field is applied to the material (a substance that exhibits a order-disorder transition from the ferromagnetic state to paramagnetic state in response to application and removal of a magnetic field). The negative magnetic material 332 exhibits different ordered states depending on whether or not a magnetic field is applied and exhibits an order-order transition between the two ordered states in response to application and removal of a magnetic field; the degree of order is higher (the degree of freedom of the system is lower) when no magnetic field is applied to the segments. Specific examples of the positive magnetic material 331 include ferromagnetic substances such as Gd and Gd-based alloys, that is, Gd-Y, Gd-Dy, Gd-Er, and Gd-Ho alloys, and meta-magnetic substances and ferromagnetic substances based on La(Fe, Si) 13 or La(Fe, Al) 13. Specific examples of the negative magnetic material 332 include substances such as a FeRH alloy which exhibit an order-order transition from the ferromagnetic state to an antiferromagnetic state in response to application and removal of a magnetic field. With the FeRh alloy, the magnitude of magnetic moment of Rh changes significantly between the two states owing to a difference in the polarization of Rh. This changes the entropy of an electron system.
In this refrigerator, first, as shown in
Then, in
Then, as shown in
Then, as shown in
The process shown in
Therefore, the above embodiment can produce effects similar to those of the second embodiment. Moreover, the cool storage section 32 includes the heat storage device 321 composed of the positive magnetic material 331 which has its temperature raised in response to an increase in the magnitude of a magnetic field and which has its temperature lowered in response to a decrease in the magnitude of the magnetic field, and the storage device 322 composed of the negative magnetic material 332 which has its temperature lowered in response to an increase in the magnitude of the magnetic field and which has its temperature raised in response to a decrease in the magnitude of the magnetic field. When heat is radiated from the refrigerant, heat can also be radiated from the magnetic materials 331 and 332. When the refrigerant absorbs heat, the magnetic materials 331 and 332 can also absorb heat. This enables more heat to be radiated and absorbed to further improve the heat exchanging efficiency of the refrigerating cycle.
FOURTH EMBODIMENTIn the description of the above embodiments, the refrigerator uses the Stirling refrigerating cycle having the four basic processes, isothermal compression, isovolumetric cooling, isothermal expansion, and isovolumetric heating. However, the fourth embodiment shows a refrigerator to which a refrigerating cycle of two basic processes, isothermal compression and isothermal expansion is applied.
In the figure, reference numeral 41 denotes a cylindrical casing in which a cylindrical cylinder main body 42 is placed. The cylinder main body 42 is open at one end and is closed at the other end. The cylinder main body 42 is filled with a gas refrigerant, for example, helium or nitrogen.
A heat storage device 43 is placed inside the cylinder main body 42 closer to the closed end. The heat storage device 43 is composed of a magnetic material 44 having its temperature changed in response to an increase or decrease in the magnitude of a magnetic field. In this embodiment, the magnetic material 44 is a positive one, for example, a GD-based material, which has its temperature raised (heat generation) in response to an increase in the magnitude of the magnetic field, while having its temperature lowered (heat absorption) in response to a decrease in the magnitude of the magnetic field. As the magnetic material 44, a porous member or a bulk material with a plurality of communication holes for external communication is used as described in
A higher-temperature heat exchanger 45 and a lower-temperature heat exchanger 46 are arranged on the respective sides of the heat storage device 43. In this case, the higher-temperature heat exchanger 45 is placed closer to the opening of the cylinder main body 42. The higher-temperature heat exchanger 45 radiates heat from a refrigerant and the heat storage device 43. The lower-temperature heat exchanger 46 is placed closer to the closed end of the cylinder main body 42. The lower-temperature heat exchanger 46 absorbs external heat on the basis of heat absorption by the refrigerant and heat storage device 43.
A piston 47 is provided in the cylinder main body 42. The piston 47 is inserted into the cylinder main body 42 through its opening to compress the refrigerant inside the cylinder main body 42. A piston shaft 48 is connected to the piston 42. A connecting bar 49 is connected to the piston shaft 48 and to a flywheel 50 at a position away from its rotating center. The connecting bar 49 thus constitutes a crank mechanism that converts a rotating motion of the flywheel 50 into a reciprocating motion to reciprocate the piston shaft 48 in the direction of arrow H in
A disk-like support plate 53 is integrally provided on the piston shaft 47. A magnetic field increasing and reducing mechanism 55 is provided on the support plate 53 via a support arm 54. The magnetic field increasing and reducing mechanism 55 is cylindrical with the cylinder main body 42 located in its hollow portion. The piston shaft 48 reciprocates in the direction of arrow H to allow the magnetic field increasing and reducing mechanism 30 to increase or reduce the magnitude of a magnetic field that is applied to the heat storage device 43. Also in this case, the magnetic field increasing and reducing mechanism 30 may be a double cylindrical magnet called a Halbach magnet, described with reference to
In the refrigerator shown in
In this refrigerator, first, as shown in
Then, as shown in
The process shown in
Therefore, also with the refrigerating cycle of two basic processes, isothermal compression and isothermal expansion, when the refrigerant generates heat, the magnetic material 44 is also allowed to radiate heat. Further, when the refrigerant absorbs heat, the magnetic material 44 is also allowed to absorb heat. This enables a refrigerating cycle with an increased heat exchange efficiency to be implemented. Such a refrigerating cycle can be implemented using the cylinder main body 42 and piston 47. This makes it possible to simplify the entire configuration of the apparatus to reduce costs.
FIFTH EMBODIMENT
In the refrigerator shown in
The cool storage section 56 has a heat storage device 431 and a heat storage device 432 arranged in parallel; the heat storage device 431 is composed of a positive magnetic material 441 having its temperature raised in response to an increase in the magnitude of a magnetic field, while having its temperature lowered in response to a decrease in the magnitude of the magnetic field, and the heat storage device 432 is composed of a negative magnetic material 442 having its temperature lowered in response to an increase in the magnitude of a magnetic field, while having its temperature raised in response to a decrease in the magnitude of the magnetic field. The positive magnetic material 441 and negative magnetic material 442 are similar to those described in the third embodiment.
In this configuration, first, as shown in
Then, as shown in
Similar repetition of the process shown in
This also makes it possible to exert effects similar to those of the fourth embodiment. Further, when the refrigerant radiates heat, the magnetic materials 441 and 442 are also allowed to radiate heat. When the refrigerant absorbs heat, the magnetic materials 441 and 442 are also allowed to absorb heat. This enables more heat to be radiated and absorbed, further increasing the heat exchange efficiency of the refrigerating cycle.
SIXTH EMBODIMENTIn the above embodiments, the magnetic field increasing and reducing mechanism is moved to enable an increase or reduction in the magnitude of a magnetic field for the heat storage device. However, a sixth embodiment keeps the magnetic field increasing and reducing mechanism stationary while enabling an increase or reduction in the magnitude of a magnetic field for the heat storage device.
In this case, the compression piston 6, expansion piston 7, heat storage device 2, higher-temperature heat exchanger 4, and lower-temperature heat exchanger 5 are arranged in the cylinder 1 filled with a refrigerant; the heat storage device 2 is composed of the magnetic material that has its temperature changed in response to an increase or decrease in the magnitude of a magnetic field.
A magnetic field increasing and reducing mechanism 61 is placed outside the cylinder 1 in association with the heat storage device 2. As shown in
This refrigerator can increase or reduce the magnitude of a magnetic field for the heat storage device by moving the yokes 63a and 63b with the permanent magnets 62a and 62b remaining stationary to open or close the magnetic path between the permanent magnets 62a and 62b. Consequently, effects similar to those of the first embodiment can be produced by repeatedly increasing or reducing the magnitude of the magnetic field in association with the isothermal compression, isovolumetric cooling, isothermal expansion, and isovolumetric heating processes, described in the first embodiment.
The magnetic field increasing and reducing mechanism 61 configured as described above is also applicable to the above second to fifth embodiments.
In the above embodiments, the magnetic material constituting the heat storage devices in the above embodiments consists of a uniform component with a fixed operating temperature. However, for example, the heat storage devices may each be composed of different components such that the operating temperature sequentially decreases from the higher-temperature heat exchanger toward the lower-temperature heat exchanger. Such a magnetic material makes it possible to emphasize the different operations of the higher- and lower-temperature heat exchangers, that is, heat generation and heat absorption. This enables more efficient heat radiation and absorption. Further, the higher-temperature heat exchanger and lower-temperature heat exchangers in the above embodiments may be composed of a magnetic material that has its temperature changed in response to an increase or decrease in the magnitude of a magnetic field. Moreover, the above embodiments all relate to the refrigerator. However, the present invention is of course applicable to a heat pump that transfers heat from a lower temperature side to a higher temperature side.
As described above, the present invention can provide a heat transporting apparatus which has good heat transporting capability and which enables an increase in heat exchange efficiency.
Additional advantages and modifications will readily occur to those skilled in the art. Therefore, the invention in its broader aspects is not limited to the specific details and representative embodiments shown and described herein. Accordingly, various modifications may be made without departing from the spirit or scope of the general inventive concept as defined by the appended claims and their equivalents.
Claims
1. A heat transporting apparatus, comprising:
- a container filled with a refrigerant;
- an operation unit which compresses the refrigerant to produce heat and expands the refrigerant to absorb heat in the container, alternately;
- a generating unit configured to generate a magnetic field which is increased and decreased, alternately;
- a thermal accumulator received in the container, to which the magnetic field is applied from the generating unit, and which produces heat depending on one of the increasing and decreasing of the magnetic field at the time of compression of the refrigerant and absorbs heat depending on the other of the increasing and decreasing of the magnetic field at the time of expansion of the refrigerant; and
- first and second heat transfer units, the first heat transfer unit transferring the heat produced in the refrigerant and the thermal accumulator to the outside of the apparatus, and the second heat transfer unit transferring external heat to the refrigerant and the magnetic unit.
2. The apparatus according to claim 1, wherein the thermal accumulator includes a positive magnetic material which produces the heat depending on the increasing of the magnetic field and which absorbs the heat depending on the decreasing of the magnetic field.
3. The apparatus according to claim 1, wherein the thermal accumulator includes a negative magnetic material which produces the heat depending on the decreasing of the magnetic field and which absorbs the heat depending on the increasing of the magnetic field.
4. The apparatus according to claim 1, wherein the thermal accumulator includes first and second magnetic segments arranged in series with a gap in the container, the first magnetic segment includes a positive magnetic material which produces the heat depending on the increasing of the magnetic field and which absorbs the heat depending on the decreasing of the magnetic field, and the second magnetic segment includes a negative magnetic material which produces the heat depending on the decreasing of the magnetic field and which absorbs the heat depending on the increasing of the magnetic field.
5. The apparatus according to claim 1, wherein the generating unit includes a magnet for generating the magnetic field and a mechanism configured to move the magnet along the container to apply the magnetic field to the magnetic unit and remove the magnetic field from the magnetic unit, alternately, in accordance with the compression and expansion of the refrigerant.
6. A heat transporting apparatus comprising:
- a cylindrical container provided with compression and expansion chambers communicating with each other and filled with a refrigerant;
- a compression piston received in the cylindrical container, which compresses the refrigerant in the expansion chamber and an expansion piston which expands the refrigerant in the expansion chamber;
- a generating unit configured to generate a magnetic field which is increased and decreased, alternately;
- a thermal accumulator received in the cylindrical container, to which the magnetic field is applied, and which produces heat depending on one of the increasing and decreasing of the magnetic field at the time of compression of the refrigerant and absorbs heat depending on the other of the increasing and decreasing of the magnetic field at the time of expansion of the refrigerant; and
- first and second heat transfer units, the first heat transfer unit transferring the heat produced in the refrigerant and the magnetic unit to the outside of the apparatus, and the second heat transfer unit transferring external heat to the refrigerant and the magnetic unit.
7. The apparatus according to claim 6, wherein the thermal accumulator includes a positive magnetic material which produces the heat depending on the increasing of the magnetic field and which absorbs the heat depending on the decreasing of the magnetic field.
8. The apparatus according to claim 6, wherein the thermal accumulator includes a negative magnetic material which produces the heat depending on the decreasing of the magnetic field and which absorbs the heat depending on the increasing of the magnetic field.
9. The apparatus according to claim 6, wherein the thermal accumulator includes first and second magnetic segments arranged in series with a gap in the container, the first magnetic segment includes a positive magnetic material which produces the heat depending on the increasing of the magnetic field and which absorbs the heat depending on the decreasing of the magnetic field, and the second magnetic segment includes a negative magnetic material which produces the heat depending on the decreasing of the magnetic field and which absorbs the heat depending on the increasing of the magnetic field.
10. The apparatus according to claim 6, wherein the generating unit includes a magnet for generating the magnetic field and a mechanism configured to move the magnet along the container to apply the magnetic field to the thermal accumulator and remove the magnetic field from the thermal accumulator, alternately, in accordance with the compression and expansion of the refrigerant.
11. The apparatus according to claim 6, wherein the generating unit includes an electric magnet which is alternatively energized and de-energized to increase and decrease the magnetic field.
12. The apparatus according to claim 6, wherein the generating unit includes a Halbach magnet.
13. A heat transporting apparatus comprising:
- a cylindrical container filled with a refrigerant;
- pistons received in the cylindrical container, which compress and expand the refrigerant;
- a generating unit configured to generate a magnetic field which is increased and decreased, alternately;
- a thermal accumulator received in the cylindrical container, to which the magnetic field is applied, and which produces heat depending on one of the increasing and decreasing of the magnetic field at the time of compression of the refrigerant and absorbs heat depending on the other of the increasing and decreasing of the magnetic field at the time of expansion of the refrigerant; and
- first and second heat transfer units, the first heat transfer unit transferring the heat produced in the refrigerant and the thermal accumulator to the outside of the apparatus, and the second heat transfer unit transferring external heat to the refrigerant and the thermal accumulator.
14. The apparatus according to claim 13, wherein the thermal accumulator includes a positive magnetic material which produces the heat depending on the increasing of the magnetic field and which absorbs the heat depending on the decreasing of the magnetic field.
15. The apparatus according to claim 13, wherein the thermal accumulator includes a negative magnetic material which produces the heat depending on the decreasing of the magnetic field and which absorbs the heat depending on the increasing of the magnetic field.
16. The apparatus according to claim 13, wherein the thermal accumulator includes first and second magnetic segments arranged in series with a gap in the container, the first magnetic segment includes a positive magnetic material which produces the heat depending on the increasing of the magnetic field and which absorbs the heat depending on the decreasing of the magnetic field, and the second magnetic segment includes a negative magnetic material which produces the heat depending on the decreasing of the magnetic field and which absorbs the heat depending on the increasing of the magnetic field.
17. The apparatus according to claim 13, wherein the generating unit includes a magnet for generating the magnetic field and a mechanism configured to move the magnet along the container to apply the magnetic field to the magnetic unit and remove the magnetic field from the magnetic unit, alternately, in accordance with the compression and expansion of the refrigerant.
18. The apparatus according to claim 13, wherein the generating unit includes an electric magnet which is alternatively energized and de-energized to increase and decrease the magnetic field.
19. The apparatus according to claim 13, wherein the generating unit includes a Halbach magnet.
20. The apparatus according to claim 1, wherein the thermal accumulator includes a magnetic material magnetic unit is made of a porous member or a bulk having communication holes.
21. The apparatus according to claim 1, wherein the thermal accumulator comprises a magnetic material formed of different components such that operating temperature sequentially decreases from a higher temperature side toward a lower temperature side in the container.
22. A refrigerator provided with the heat transporting apparatus according to claim 1.
23. A heat pump provided with the heat transporting apparatus according to claim 1.
Type: Application
Filed: Sep 19, 2006
Publication Date: Jun 7, 2007
Inventors: Hideo IWASAKI (Kawasaki-shi), Akihiro KASAHARA (Sambu-gun), Katsumi HISANO (Matsudo-shi), Akihiro KOGA (Tokyo), Akiko SAITO (Kawasaki-shi), Tadahiko KOBAYASHI (Yokohama-shi), Takuya TAKAHASHI (Tokyo)
Application Number: 11/533,163
International Classification: F25B 21/00 (20060101);