JP2014095535A - Magnetic air-heating and cooling apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a magnetic air-heating and cooling apparatus capable of applying intense magnetism with magneto-caloric materials.SOLUTION: Magneto-caloric materials 11 to 18 having two pieces in the radial direction (array direction), four arrays in the circumferential direction and eight pieces in the sum are arranged respectively at intervals, magnet structural bodies 21 and 25, 22 and 26, 23 and 27, and 24 and 28 which assume an upper and lower pair are arranged so as to hold the magneto-caloric materials 11 to 18 between the upper side and lower side upon magnetism application, in every other arrangement with respect to the array direction and the circumferential direction, and the respective magneto-caloric materials to constitute a magnetic circuit. In a magnetic air-heating and cooling apparatus, the respective magnet structural bodies 21 to 28 are made of a plurality of permanent magnets having a Halbach array in which directions of magnetization are different from each other and are arranged such that both directions of magnetic field lines formed by the magnet structural bodies get to the same direction between a pair of magnet structural bodies 21, 25.

Description

  The present invention relates to a magnetic air conditioner.

  Most of refrigeration apparatuses conventionally used at room temperature, such as refrigerators, freezers, and air conditioners, use heat transfer of gaseous refrigerants such as CFCs and CFCs. Recently, the problem of ozone depletion due to the emission of chlorofluorocarbons has been exposed, and there is also concern about the impact on global warming caused by the emission of alternative chlorofluorocarbons. For this reason, there is a strong demand for the development of an innovative refrigeration apparatus that is clean and has a high heat transport capability, replacing the refrigeration apparatus that uses a gaseous refrigerant such as chlorofluorocarbon gas or alternative chlorofluorocarbon gas.

  Against this background, the refrigeration technology that has recently attracted attention is the magnetic refrigeration technology. Some magnetic materials exhibit a so-called magnetocaloric effect (MCE) in which the temperature of the magnetic material changes according to the change in the magnitude of the magnetic field applied to the magnetic material. Such a magnetic substance that changes in temperature due to the magnetocaloric effect is called a magnetocaloric material (MCM) (sometimes called a magnetocaloric effect material). A refrigeration technique that transports heat using a magnetic material that exhibits this magnetocaloric effect is a magnetic refrigeration technique.

  As an application of the magnetic refrigeration technology, for example, there is a magnetic air conditioner that transports heat using heat transfer of a solid substance (Patent Document 1). This magnetic air conditioner transmits heat by the following configuration.

  A positive magnetocaloric material whose temperature increases when magnetism is applied and a negative magnetocaloric material whose temperature decreases when magnetism is applied are alternately arranged at predetermined intervals. One magnetocaloric material block is formed by a pair of positive and negative magnetocaloric materials. A plurality of magnetocaloric material blocks are arranged annularly to form a magnetocaloric material unit. The heat transfer member inserted and removed between the positive and negative magnetocaloric materials arranged in the magnetocaloric material unit is arranged between the positive and negative magnetocaloric materials. A permanent magnet is arranged on a hub-like rotating body that is concentric with the magnetocaloric material unit and has substantially the same inner diameter and outer diameter to form a magnetic circuit. And the rotary body in which the permanent magnet is arrange | positioned is arrange | positioned so as to oppose a magnetocaloric material unit, and it rotates relatively with respect to a magnetocaloric material unit. The rotation of the rotating body simultaneously applies and removes magnetism to the positive and negative magnetocaloric materials. As the rotating body rotates, the heat transfer member is inserted and removed between the positive and negative magnetocaloric materials at a fixed timing. The heat generated by the magnetocaloric material due to the magnetocaloric effect is transported in one direction in which the magnetocaloric material is disposed via the heat transfer member.

  In such a magnetic air conditioner, a permanent magnet is used in which a magnetic circuit for applying magnetism to a magnetocaloric material is rotated by 90 ° in an annular Halbach array so that the end of the magnet is eliminated. There is a configured technology (Patent Document 2).

  In this technology, a pair of annular Halbach array permanent magnet magnetic circuits are arranged so that their magnetic poles face each other, and a magnetocaloric material is arranged therebetween.

JP 2007-147209 A JP 2011-226735 A

  However, in the technique of Patent Document 2, in the portion where the magnetocaloric material is disposed between the paired permanent magnets, the direction of the magnetic lines of force is opposite to the direction of the magnetic lines of force formed by the respective permanent magnets. The part which becomes the same is made. Since the magnetic force acting on the magnetocaloric material is weakened in the part where the direction of the magnetic field lines is opposite, the part where the direction of the magnetic field lines is opposite cannot be used for applying the magnetic field. Therefore, in the prior art, only the part where the direction of the magnetic field lines is the same is used to apply magnetism (magnetic field) to the magnetocaloric material.

  For this reason, in a prior art, a large amount of magnets will be used with respect to the usage-amount of a magnetocaloric material, and the utilization efficiency of a permanent magnet will be bad.

  SUMMARY OF THE INVENTION An object of the present invention is to provide a magnetic air conditioner that can generate a strong magnetic field with a magnetic circuit and has a high utilization efficiency of a permanent magnet.

  In order to achieve the above object, a magnetic air-conditioning apparatus according to the present invention is arranged in rows at intervals, and each of a plurality of magnetocaloric materials that change temperature by applying and removing magnetism and a plurality of magnetocaloric materials. And a magnetic circuit for applying and removing the magnetism. This magnetic circuit is composed of a pair of magnet structures sandwiching the magnetocaloric material in a state where magnetism is applied to the magnetocaloric material. This magnet structure is composed of a plurality of permanent magnets having a Halbach arrangement in which the directions of magnetization are different from each other, and the direction of the lines of magnetic force formed by the magnet structure is both between the pair of magnet structures. Both are in the same direction.

  According to the magnetic air conditioner according to the present invention, a magnetocaloric material is disposed between a pair of magnet structures composed of a plurality of permanent magnets each having a Halbach array having different magnetization directions. And the direction of the magnetic force line which generate | occur | produces by each of a pair of magnet structure was made to become the same direction between a pair of magnet structures. Thereby, since the magnetic force which acts between a pair of magnet structures becomes the same direction, stronger magnetism can be applied to the magnetocaloric material between them. Therefore, a strong magnetism (magnetic field) can be efficiently applied to the magnetocaloric material with a small number of permanent magnets.

It is a schematic perspective view for demonstrating the structure of the magnetic air conditioning apparatus of embodiment. It is sectional drawing of the radial direction of a magnetic air conditioning apparatus. It is a figure for demonstrating the structure of a magnet structure, Comprising: It is sectional drawing which shows the magnet structure which became a pair, and the magnetocaloric material between them. It is a figure which shows the other example of the magnet structure of a Halbach arrangement. It is a figure which shows the other example of the magnet structure of a Halbach arrangement. It is a figure which shows the example which has arrange | positioned the member which consists of a soft-magnetic material to the both ends of the row | line | column of the permanent magnet made into the Halbach arrangement | sequence. (A) is a figure which shows the model of Example 1, (b) is the figure output by the computer which shows the magnetic characteristic profile which is a simulation result of the magnetic field analysis by the model of Example 1. FIG. (A) is a figure which shows the model of the comparative example 1, (b) is the figure output by the computer which shows the magnetic characteristic profile which is the simulation result of the magnetic field analysis by the model of the comparative example 1. (A) is a figure which shows the model of the comparative example 2, (b) is the figure output by the computer which shows the magnetic characteristic profile which is a simulation result of the magnetic field analysis by the model of the comparative example 2. (A) is a figure which shows the model of Example 2, (b) is the figure output by the computer which shows the magnetic characteristic profile which is a simulation result of the magnetic field analysis by the model of Example 2. FIG. (A) is a figure which shows the model of Example 3, (b) is the figure output by the computer which shows the magnetic characteristic profile which is a simulation result of the magnetic field analysis by the model of Example 3. FIG. It is sectional drawing of the diameter direction of the magnetic heating apparatus in Embodiment 2. FIG. (A) is a top view which shows arrangement | positioning of the magnetocaloric material in Embodiment 2, (b) is a top view which shows arrangement | positioning of the magnet structure in Embodiment 2. FIG. It is a figure for demonstrating the effect | action of Embodiment 2, and is the elements on larger scale of a magnetic heating apparatus. It is an enlarged view of a laminated form with a yoke for comparison with the second embodiment.

  Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings. In the description of the drawings, the same elements are denoted by the same reference numerals, and redundant description is omitted. In addition, the dimensional ratios in the drawings are exaggerated for convenience of explanation, and are different from the actual ratios.

(Embodiment 1)
FIG. 1 is a schematic exploded perspective view for explaining the configuration of the magnetic air conditioner according to the embodiment. Moreover, FIG. 2 is sectional drawing of the radial direction of a magnetic air conditioning apparatus.

  The magnetic cooling / heating apparatus 1 shown in the figure has a cylindrical outer shape, and moves heat from the center to the outer circumferential direction. For this reason, a total of eight magnetocaloric materials 11 to 18 are arranged at intervals, two in the radial direction (row direction) and four in the circumferential direction.

  And so that the magnetocaloric material is sandwiched from above and below when magnetism is applied, a pair of upper and lower magnet structures 21 to 28 are arranged so as to be alternately arranged with respect to the magnetocaloric material in the circumferential direction and the column direction, respectively. This constitutes a magnetic circuit. Here, the magnet structures 21 and 25, 22 and 26, 23 and 27, and 24 and 28 are paired (the upper side is 21 to 24 and the lower side is 25 to 28). For example, when the radial cross section of the portions of the magnetocaloric materials 11 and 15 is viewed, a pair of magnet structures 21 and 25 are positioned above and below the magnetocaloric material 11 as shown in FIG. 11 is in a state in which magnetism is applied.

  Each of the magnet structures 21 to 24 and 25 to 28 is fixed to a disk-shaped substrate 20, and each substrate 20 rotates in conjunction with each other so that the magnetocaloric materials 11 to 18 are magnetized from above and below. Apply and remove. The board | substrate 20 is connected with respect to the low temperature side heat exchanger 41 (after-mentioned) by bearings (not shown), such as a ball bearing, so that rotation is possible.

  Each of the magnet structures 21 to 28 has a structure in which each magnet structure is a Halbach array of a plurality of permanent magnets. The detailed structure of the magnet structure will be described later.

  A low temperature side heat exchanger 41 is provided at the center of the magnetic air conditioner, and a high temperature side heat exchanger 42 is provided at the outer periphery (in the case where the two are not distinguished from each other, simply referred to as a heat exchanger). The low temperature side heat exchanger 41 may be configured such that, for example, heat can be further transferred by flowing a fluid through a cylindrical heat conducting member or inside the cylindrical shape. On the other hand, the high temperature side heat exchanger 42 is connected to a casing (not shown) whose outer shape covers the magnetic air conditioner 1 and discharges heat to the outside. The cylindrical housing may be provided with heat radiating fins, or the heat may be further transferred by flowing a fluid through the high temperature side heat exchanger 42.

  Between the low-temperature side heat exchanger 41, the magnetocaloric materials 11 to 18 and the high-temperature side heat exchanger 42 in the respective column directions, that is, between the low-temperature side heat exchanger 41 and the magnetocaloric material 15, the magnetocaloric material 15 11, and between the magnetocaloric material 11 and the high temperature side heat exchanger 42, thermal switches 31, 32, 33 are provided. Between the low temperature side heat exchanger 41 and the magnetocaloric material 16, between the magnetocaloric material 16 and 12, between the magnetocaloric material 12 and the high temperature side heat exchanger 42, and between the low temperature side heat exchanger 41 and the magnetocaloric material 17 , Between the magnetocaloric material 17 and 13, between the magnetocaloric material 13 and the high temperature side heat exchanger 42, between the low temperature side heat exchanger 41 and the magnetocaloric material 18, between the magnetocaloric material 18 and 14, and the magnetocaloric material. 14 and the high temperature side heat exchanger 42 (hereinafter sometimes referred to as a magnetocaloric material, etc.) are also provided with thermal switches 31, 32, 33 in order from the center side. In FIG. 1, the illustration is omitted for the sake of easy viewing.

  Further, between the respective circumferential directions of the magnetocaloric materials 11 to 18 are thermally isolated from each other by a space or a heat insulating material.

  Hereinafter, each part of the magnetic air conditioning apparatus comprised in this way is demonstrated.

  As the magnetocaloric materials 11 to 18, either a positive magnetocaloric material that generates heat and absorbs heat when applied with magnetism, or a negative magnetocaloric material that generates heat when absorbed and removed with magnetism is used. A positive magnetocaloric material and a negative magnetocaloric material are opposite in the magnetocaloric effect that is manifested, and differ in the type of magnetocaloric effect. In this embodiment, a positive magnetocaloric material that is cheaper than a negative magnetocaloric material is used. This is because the negative magnetocaloric material must be manufactured from a rare magnetocaloric material, which is costly and the magnitude of the magnetocaloric effect of the negative magnetocaloric material is that of the magnetocaloric effect of the positive magnetocaloric material. This is because it is smaller than the size.

The thermal switches 31 to 33 are all the same, and transfer and block heat between magnetocaloric materials and the like. As the thermal switch, for example, a metal / insulating phase transition body can be used. When a voltage is applied to a metal / insulating phase transition body, the phase transition from the insulator to the metal increases, and the thermal conductivity increases. Conversely, when the voltage is cut off, the phase transition from the metal to the insulator causes a decrease in thermal conductivity. It has a property. An insulator exhibiting a phase transition between a metal and an insulator is an inorganic oxide mott insulator or an organic mott insulator. The inorganic oxide Mott insulator includes at least a transition metal element. As the Mott insulator, LaTiO ₃ , SrRuO ₄ , and BEDT-TTF (TCNQ) are known. Currently known devices capable of phase transition between metal and insulator include a ZnO single crystal thin film electric double layer FET and a TMTSF / TCNQ stacked FET element. Heat can be transferred by thermionic and lattice crystals. The ZnO single crystal thin film electric double layer FET and the TMTSF / TCNQ stacked FET element utilize the property that the thermal electrons move actively when a voltage is applied. More specifically, an inorganic oxide Mott insulator, an organic Mott insulator, a ZnO single crystal thin film electric double layer FET, a TMTSF / TCNQ stacked FET element, etc. containing at least a transition metal element in a metal / insulating phase transition body, It is preferable to use a material whose thermal conductivity changes greatly by applying and removing voltage.

  The thermal switches 31 to 33 are not limited to those using such a metal / insulating phase transition body, and various other forms may be used. For example, you may use the heat conductive member attached to the disk which fixed the magnet structure, and moving between magnetocaloric materials etc. by rotation of a disk. As the heat conducting member, a metal having good heat conduction, such as aluminum, nickel, iron, or alloys of various metals can be used.

  The magnet structures 21 to 28 will be described. FIG. 3 is a view for explaining the configuration of the magnet structure, and is a cross-sectional view showing a pair of magnet structures and a magnetocaloric material therebetween.

  Each magnet structure used in this embodiment is formed by joining and integrating a plurality of permanent magnets having different magnetization directions.

  The magnet structure 21 includes three permanent magnets in a Halbach array that are gradually changed by 90 degrees as one set, and two sets of these magnets are joined in succession to form a row of a total of six permanent magnets. The direction of magnetization of each permanent magnet in each of the sets 211 and 212 is set so that the directions in which the magnetization direction changes are opposite to each other. That is, the first set 211 starts with a permanent magnet 201 whose magnetization direction is upward (this is assumed to be 0 degree), changes to 90 degrees counterclockwise, and further changes to 90 degrees counterclockwise. It consists of a magnet 203. The second set 212 changes so that the magnetization direction rotates in the reverse direction to the first set 211. In other words, the three permanent magnets 201, 204, and 203 are arranged so as to change clockwise until 90 degrees reaches 180 degrees. In the figure, arrows in the permanent magnets indicate the direction of magnetization, and permanent magnets having the same magnetization direction are denoted by the same reference numerals (the same applies to other figures).

  The magnet structure 25 that forms a pair with the magnet structure 21 uses two sets of a plurality of permanent magnets similarly arranged in a Halbach array, but is arranged so that the magnetization direction of each permanent magnet is opposite to that of the magnet structure 21. It is. That is, the first set 251 of the magnet structure 25 is arranged so as to be a permanent magnet 204 that changes 90 degrees clockwise, and a permanent magnet 201 that changes 90 degrees clockwise, starting from the downward permanent magnet 203. Yes. The second set 252 is arranged with three permanent magnets 203, 202, 201 in the reverse rotation direction (counterclockwise).

  As a result, in the magnet structures 21 and 25 that form a pair, the permanent magnets that constitute each of the magnet structures 21 and 25 are in the opposite directions between the permanent magnets that are in positions facing each other.

  The magnet structure configured in this manner generates a magnetic field with the shape of approximately 8 in the horizontal direction. In the figure, a relatively strong magnetic field is indicated by a solid line, a weak magnetic field is indicated by a dotted line, and the direction of the magnetic force lines in the magnetic field generated by these arrows is indicated (the same applies to each figure described later).

  Focusing on one magnet structure 21, the first set 211 on the left side generates a strong magnetic field on the lower side and the second set 212 on the right side generates a weak magnetic field on the lower side.

  On the other hand, in the magnet structure 25 in which the magnetization direction of each permanent magnet is reversed with respect to the magnet structure 21, the first set 251 on the left side generates a weak magnetic field on the upper side and the second set on the right side. 212 is weak at the top and a strong magnetic field is generated at the bottom.

  That is, the magnet structure can form a strong magnetic field in a specific direction, here, above or below the magnet structure, by a plurality of permanent magnets having such a Halbach array.

  As a result, the direction of the lines of magnetic force generated by the magnet structures 21 and 25 is the same between the pair of upper and lower magnet structures 21 and 25, that is, in the portion where the magnetocaloric material 11 is present. Therefore, the magnetism (magnetic field) strengthened by the pair of upper and lower magnet structures 21 and 25 is applied to the magnetocaloric material 11 disposed between the pair of upper and lower magnet structures 21 and 25. In the figure, the left magnetic field lines are formed between the pair of magnet structures 21 and 25. However, the pair of magnet structures 21 and 25 may be arranged upside down so as to be reversed.

  The number of permanent magnets having such a Halbach array is not limited to six, and various variations are possible.

  4 and 5 are diagrams showing another example of the magnet structure of the Halbach array.

  For example, in the example of FIG. 4, each of the pair of magnet structures 21 and 25 is constituted by 10 magnets.

  The magnet structure 21 includes five permanent magnets 201, 205, 202, 206, and 203 in a Halbach array in which the magnetization direction is gradually changed by 45 degrees in a counterclockwise direction until reaching 180 degrees. The permanent magnets 201, 207, 204, 208, 203 whose magnetization direction gradually changes in the clockwise direction are joined as a second set. The generated magnetic field is a magnetic field in which a figure of 8 is placed horizontally, and is strong at the top in the first set 211 and weak at the bottom. In the second set 212, it is strong at the bottom and weak at the top.

  The magnet structure 25 includes five permanent magnets 203, 208, 204, 207, 201 in a Halbach array in which the direction of magnetization is gradually changed by 45 degrees and counterclockwise until it reaches 180 degrees in a first set 251. The permanent magnets 203, 206, 204, 208, 201 whose magnetization direction gradually changes clockwise are joined as a second set. The generated magnetic field is a magnetic field in which the figure of 8 is placed horizontally, and is strong at the top in the first set 251 and weak at the bottom. The second set 252 is strong at the bottom and weak at the top.

  Thus, even if the number of permanent magnets constituting one magnet structure is increased, a strong magnetic field can be obtained between the magnet structures 21 and 25 with the lines of magnetic force directed in the same direction.

  In the examples of FIGS. 5A and 5B, only one set is used. FIG. 54 (a) shows that one permanent magnet 201, 202, 203 has a magnetization structure shifted by 90 degrees to form a Halbach array, one magnet structure 21, and similarly three permanent magnets 203, 204, 201. One magnet structure 25 is formed and these are paired.

  FIG. 5B shows a magnet structure including five permanent magnets 201, 205, 202, 206, and 203 in a Halbach array in which the magnetization direction is gradually changed by 45 degrees and counterclockwise until 180 degrees. The body 21 is comprised, and the magnet structure 25 is comprised similarly by the five permanent magnets 203,208,204,207,201.

  Thus, even with one set of magnet structures, a strong magnetic field is generated on the upper side and a weak magnetic field is generated on the lower side, as described with reference to FIGS. In between, a strong magnetic field can be obtained in which the magnetic field lines are directed in the same direction.

  In addition to these, one set may be composed of more permanent magnets, or one magnet structure may be composed of more sets.

  FIG. 6 is a diagram showing an example in which members made of a soft magnetic material are arranged at both ends of a permanent magnet array in a Halbach array.

  The pair of magnet structures 21 and 25 shown in FIG. 6 are members in which members of soft magnetic material (referred to as soft magnetic members 50) are arranged at both ends of the permanent magnet rows of the magnet structures 21 and 25, respectively. By arranging the soft magnetic members 50 at both ends of the row of permanent magnets in this way, the magnetic field that appears outside the magnetocaloric material 11 is weakened, and the magnetic force applied to the magnetocaloric material 11 is further increased accordingly. be able to. The soft magnetic members 50 provided at both ends of the magnet structures 21 and 25 do not need to be magnetized (that is, become magnets).

  Here, the soft magnetic material is a material having a small coercive force and a large magnetic permeability. For example, iron, silicon steel and permalloy. On the other hand, there is a hard magnetic material as a term for the soft magnetic material, which is a material having a large coercive force. Also in the present embodiment, a hard magnet material is used for the permanent magnets arranged in the Halbach array. As a hard magnetic material used as a permanent magnet arranged in Halbach, various magnets such as an alnico magnet, a ferrite magnet, a samarium cobalt magnet, a neodymium magnet, and a samarium iron nitrogen magnet can be used.

  In FIG. 6, a magnet structure composed of six permanent magnets is shown as an example. However, even in a row of other permanent magnets such as three, five, ten, etc., soft magnets are formed at both ends in the same manner. By disposing the member 50, the magnetic field that appears outside the magnetocaloric material 11 can be weakened, and the magnetic force applied to the magnetocaloric material 11 can be further increased accordingly.

  In the magnetic structures 21 and 25 configured in this way, the arrangement direction of the individual permanent magnets (not the magnetization direction of the individual permanent magnets) may be the radial direction in the magnetic air conditioner shown in FIG. It may be in the circumferential direction.

  As described above, the structure of the magnet structure has been described by taking the pair of magnet structures 21 and 25 arranged above and below the magnetocaloric material 11 as an example, but the other pair of magnet structures 22 and 26, 23 and 27, 24. And 28 have the same structure.

  Next, with respect to the magnet structures 21 and 25 composed of the permanent magnet rows in the Halbach array in these embodiments, the configuration of the permanent magnets (magnetization direction, arrangement, number, etc. of the permanent magnets) is variously changed to change the magnetic field distribution. The simulation result will be described.

  For the magnetic field analysis, FEMM 4.2 which is a two-dimensional finite element method magnetic field analysis software was used. The calculation used this software to automatically generate a mesh. As a permanent magnet to be analyzed, a neodymium magnet (NdFeB) that this software has by default to generate a magnetic property profile by simulation is used. The magnetization direction of the permanent magnet is the direction indicated by the arrow “→” in FIGS.

Example 1
FIG. 7A is a diagram illustrating a model of the first embodiment. In Example 1, a permanent magnet row having the same structure as that shown in FIG. 4 was used as a model. That is, in one magnet structure, a total of 10 permanent magnets joined together by reversing the rotation of the magnetization direction and joining 5 sets of 5 permanent magnets arranged in a Halbach array with the magnetization direction shifted by 45 degrees. A row of magnets. This magnet structure is made up of a pair of upper and lower parts 21 and 25, and is arranged with a gap so that the magnetization directions of the individual permanent magnets constituting the pair of magnet structures 21 and 25 are opposite to each other. The size was the same for the pair of magnet components 21 and 25, and the entire length of one magnet component was 200 mm and the height was 20 mm. One permanent magnet has a length of 20 mm on one side and is arranged to be 200 mm. The interval between the upper and lower magnet components was 2 mm. Since the simulation analyzes the magnetic force in two dimensions, there is no depth in this model (the same applies to the simulation models of other examples and comparative examples).

  FIG. 7B is a computer output diagram showing a magnetic characteristic profile which is a simulation result of magnetic field analysis by the model of the first embodiment. As shown in the figure, the magnetic field lines indicating the strength of the magnetic field generated outside the magnet structure include the upper part of the left one set part of the magnet structure located above and the right set of the magnet structure located below. Although it overhangs slightly under the part, it turns out that there is almost no other part. Therefore, it can be seen that there is little leakage of magnetic flux to the outside of the paired upper and lower magnet structures. The strength of the magnetic field is the magnetic flux density (indicated by T (Tesla)).

(Comparative Example 1)
FIG. 8A is a diagram illustrating a model of the first comparative example. The model of Comparative Example 1 is one permanent magnet having a height of 200 mm and a total length of 200 mm. A yoke 101 facing the magnet 100 is provided. The yoke has a height of 20 mm. However, only the portion facing the magnet 100 is set to 40 mm in order to have a thickness corresponding to the magnet 100. The distance between the magnet 100 and the yoke 101 was 2 mm as in the first embodiment. Further, the magnetization direction of the magnet 100 (the magnetization direction of each permanent magnet) is the direction of the gap with the yoke 101.

  FIG. 8B is a computer output diagram showing a magnetic characteristic profile which is a simulation result of magnetic field analysis using the model of Comparative Example 1.

  As shown in the figure, in the model of Comparative Example 1, almost all of the magnetic field lines indicating the magnetic field generated by the permanent magnet pass through the yoke. Therefore, there is a strong magnetic field in the gap between the permanent magnet and the yoke.

  Here, when Example 1 is compared with Comparative Example 1, in Example 1 in which the Halbach array is used, the leakage of magnetic flux is very small even though the yoke that serves as a path of magnetic lines is not used. Therefore, it can be seen that sufficient magnetism can be applied to the magnetocaloric material as a magnetic refrigeration apparatus without using a yoke. For this reason, it is suitable as a magnetic air conditioner for reducing the size and weight.

  The yoke generally uses an iron material, and, as can be seen from FIG. 8A, the weight increases and the size increases because it is necessary to form a path for the lines of magnetic force at portions other than the magnet. On the other hand, in Example 1, since leakage of magnetic flux can be eliminated with only a magnet, the size and weight can be reduced accordingly.

(Comparative Example 2)
Further, a simulation was performed for the case where the magnetization directions of the permanent magnets in the rows of permanent magnets forming the upper and lower magnet structures were made the same using a pair of upper and lower magnet structures in the Halbach array.

  FIG. 9A is a diagram illustrating a model of the second comparative example. As shown in the drawing, in this comparative example 2, ten permanent magnets having a Halbach array are used as the permanent magnets forming the upper and lower magnet structures 121 and 125, but a pair of magnet structures 121 and 125 is used. Both have the same magnetization direction. The rest is the same as the first embodiment. Since the dimensions of each part are the same, they are not shown.

  FIG. 9B is a computer output diagram showing a magnetic characteristic profile which is a simulation result of magnetic field analysis by the model of Comparative Example 2.

  As shown in the drawing, in Comparative Example 2, there are more lines of magnetic force appearing outside the magnet than in Example 1, and leakage of magnetic flux is recognized. Therefore, when a pair of magnet structures arranged in the same Halbach array are used, the effect of confining the magnetic flux can be obtained by making the magnetization directions of the plurality of permanent magnets constituting each of them reverse in the vertical direction as in the first embodiment. Is high.

(Example 2)
FIG. 10A is a diagram illustrating a model of the second embodiment. In the second embodiment, similarly to the structure shown in FIG. 3, two permanent magnets in which one magnet structure is arranged in a Halbach array with the magnetization direction shifted by 90 degrees are set as one set, and the magnetization direction is reversed. A total of six pieces joined in series are used. The magnet constituents are paired up and down, and are arranged with a gap so that the magnetization directions of the individual permanent magnets constituting the pair of magnet constituents 21 and 25 are opposite to each other. The dimensions of each part were 50 mm in total length and 5 mm in height. The gap was 5 mm. The length of each permanent magnet in the precursor direction is a size (about 8.3 mm) obtained by dividing the total length of 50 mm into six.

  FIG. 10B is a computer output diagram showing a magnetic characteristic profile which is a simulation result of magnetic field analysis using the model of the second embodiment.

  As shown in the figure, in Example 2, the leakage of magnetic flux is recognized as compared with Example 1. However, most of the magnetic flux is confined in the pair of upper and lower magnet structures 21 and 25. Therefore, it can be seen that there is an effect of confining the magnetic flux even if the number of permanent magnets arranged in the Halbach array is reduced.

(Example 3)
Next, as Example 3, a simulation was performed using a model in which a soft magnetic material was disposed and joined to both ends of a permanent magnet array arranged in Halbach. The soft magnetic material was assumed to be iron (Fe).

  FIG. 11A is a diagram illustrating a model of the third embodiment. In Example 3, a total of six magnets were joined by joining two sets of three permanent magnets in which the magnetization directions were shifted by 90 degrees and arranged in Halbach as one set, and the magnetization directions were reversed. It consists of a permanent magnet. The magnet constituents are paired up and down, and are arranged with a gap so that the magnetization directions of the individual permanent magnets constituting the pair of magnet constituents 21 and 25 are opposite to each other. And the soft-magnetic member 50 was joined to the both ends of this row | line | column of this permanent magnet.

  FIG. 11B is a computer output diagram showing a magnetic characteristic profile which is a simulation result of magnetic field analysis using the model of the third embodiment.

  As shown in the drawing, it can be seen that in Example 3, the leakage of magnetic flux at both ends of the permanent magnet array is less than that in Example 2. Therefore, it is possible to concentrate more magnetic flux on the magnetocaloric material 11 by disposing the soft magnetic material at both ends of the permanent magnet row.

  Next, the operation of the magnetic air conditioner will be described. Here, as already explained, a positive magnetocaloric material is used. Therefore, the magnetocaloric material increases in temperature when magnetized, and decreases in demagnetization when the magnetism is removed.

  In the state shown in FIG. 1, when focusing on the rows of the magnetocaloric materials 11 and 15, a pair of magnet structures 21 and 25 are positioned above and below the magnetocaloric material 11. For this reason, the magnetocaloric material 11 is in a state where magnetism is applied (at the time of excitation), and the temperature of the magnetocaloric material 11 rises. On the other hand, since the magnetocaloric material 15 has no magnet structure and no magnetism is applied (during demagnetization), the temperature of the magnetocaloric material 15 decreases.

  In this state, the thermal switch 32 between the magnetocaloric materials 11 and 15 is off and the magnetocaloric materials 11 and 15 are insulated. On the other hand, the heat switches 31 and 32 between the heat exchangers 41 and 42 are turned on, from the low temperature side heat exchanger 41 to the magnetocaloric material 15, and from the magnetocaloric material 11 to the high temperature side heat exchanger 42, respectively. Heat conduction is started.

  Next, the substrate 20 rotates 45 degrees from the position shown in FIG. As a result, the pair of magnet structures 21 and 25 located above and below the magnetocaloric material 11 move to the position of the magnetocaloric material 12 and disappear from the position of the magnetocaloric material 11. At the same time, the pair of magnet structures 24 and 28 come to the position of the magnetocaloric material 15. Since the magnetocaloric material 11 is demagnetized, it is demagnetized and absorbs heat to lower the temperature. On the other hand, the magnetocaloric material 15 is magnetized and excited to generate heat and increase its temperature. At this time, the thermal switch 32 is on, and heat is conducted between the magnetocaloric materials 11 and 15. On the other hand, the heat switches 31 and 32 between the heat exchangers 41 and 42 are turned off, and between the low temperature side heat exchanger 41 and the magnetic heat quantity material 15 and between the magnetic heat quantity material 11 and the high temperature side heat exchanger 42, respectively. Is insulated.

  Thereafter, this operation is repeated by rotating the substrate 20 by 45 degrees, and heat is transferred from the low temperature side heat exchanger 41 to the high temperature side heat exchanger 42. The other rows of magnetocaloric materials (magnetocaloric materials 12 and 16, 13 and 17, 14 and 18) operate in the same manner, and the entire apparatus is heated from the low temperature side heat exchanger 41 at the center to the outer peripheral high temperature side heat. Heat is transferred to the exchanger 42.

(Embodiment 2)
FIG. 12 is a schematic cross-sectional view in the diameter direction of the magnetic heating device according to the second embodiment. Fig.13 (a) is a top view which shows arrangement | positioning of a magnetocaloric material, FIG.13 (b) is a top view which shows arrangement | positioning of a magnet structure.

  The magnetic heating device 2 of the second embodiment is based on the magnetic heating device of the first embodiment described above, and has a total of 72 magnetocaloric materials 11 arranged in the radial direction (row direction) and 12 in the circumferential direction. These magnetocaloric materials 11 are arranged in a disk shape. In the figure, four layers of the magnetocaloric material 11 arranged in a disk shape are laminated. There is no limit on the number of layers, and any number of layers may be stacked. The greater the number of layers, the higher the cooling capacity.

  Magnet structures 21 and 25 are stacked so as to sandwich the magnetocaloric material 11 arranged in a disk shape from above and below. That is, the magnetic heating device 2 includes the magnetocaloric material 11 and the magnet so that the magnet structure 21, the magnetocaloric material 11, the magnet structure 25, the magnetocaloric material 11, the magnet structure 21,. Structures 21 and 25 are alternately stacked.

  Between the radial direction (column direction) of the magnetocaloric material 11 arranged in a disk shape, a thermal switch 30 is arranged. Moreover, the low temperature side heat exchanger 41 is provided in the center of a disk, and the high temperature side heat exchanger 42 is provided in the outer periphery of the disk. There is also a heat switch 30 between the low temperature side heat exchanger 41 and the innermost magnetocaloric material 11. Similarly, there is a thermal switch 30 between the high temperature side heat exchanger 42 and the outermost magnetocaloric material 11.

  In addition, the radial rows of the magnetocaloric material 11 and the thermal switch 30 are separated by a heat insulating material 80 or the like. The heat insulating material 80 may be filled with a resin material or the like, or may be an air layer with a gap.

  The magnetocaloric material 11, the heat switch 30, and the heat insulating material 80 are integrated into a disk shape and are connected to the low temperature side heat exchanger 41 via the heat switch 30 located on the innermost periphery. .

  A fluid can flow inside the low temperature side heat exchanger 41. Further, the high temperature side heat exchanger 42 is hollow inside, and an inlet 43 a and an outlet 43 b are provided at the end of the high temperature side heat exchanger 42, and a fluid flows through the high temperature side heat exchanger 42. (The fluid flows in the direction of the arrow in the figure).

  The magnet structures 21 and 25 are respectively fixed to the disk-shaped substrate 20 and arranged so as to be alternately arranged with respect to the magnetocaloric material 11 in both the column direction and the circumferential direction.

  The magnet structures 21 and 25 are composed of a plurality of permanent magnets having the Halbach arrangement already described. And the magnetization directions in the plurality of permanent magnets having the Halbach array in the magnet structures 21 and 25 are opposite to each other. The magnet structures 21 and 25 may have soft magnetic members 50 at both ends.

  Each substrate 20 to which the magnet structures 21 and 25 are fixed is rotatably supported by a bearing 618 (for example, a ball bearing) with respect to the low temperature side heat exchanger 41 inside thereof. On the other hand, the outer side is rotatably supported by bearings 62 (for example, ball bearings) provided above and below the high temperature side heat exchanger 42. A gear 73 is provided on the outer periphery of the substrate 20. The gear 73 is engaged with a gear 71 that is rotated by a motor 70 and a shaft 72. The gear 71 rotates in conjunction with the shaft 72. As a result, all the substrates 20 are rotated in synchronization with the rotation of the motor 70.

  The uppermost layer and the lowermost substrate 20 in the stacking direction are supported by a bearing 62 so as to be rotatable with respect to a part 85 of the housing.

  The operation of the magnetic heating device 2 configured in this way is basically the same as that of the first embodiment. That is, when the substrate 20 is rotated, the magnet structures 21 and 25 successively apply and remove magnetism to the magnetocaloric material 11, and accordingly, the magnetocaloric material 11 generates heat and absorbs heat. At this time, heat is transferred from the inside to the outside by interlocking the on (heat transfer state) and off (non-heat transfer state) of each heat switch 30, and the low temperature side heat exchanger 41 to the high temperature side heat exchanger 42. Heat transfer takes place.

  FIG. 14 is a partial enlarged view of the magnetic heating device for explaining the operation of the second embodiment. FIG. 15 is an enlarged view of a laminated form with a yoke for comparison with the second embodiment.

  Focusing on one magnetocaloric material 11, in the second embodiment, a pair of magnet structures 21 and 25 are arranged above and below one magnetocaloric material 11, as shown in FIG. This is all the same in each layer. That is, in Embodiment 2, the magnet structure and the magnetocaloric material are alternately laminated.

  On the other hand, in the laminated form with yoke, as shown in FIG. 15, one permanent magnet 100 is arranged on the upper side of one magnetocaloric material 11, and the yoke 101 is arranged so that the magnetic field of this permanent magnet 100 does not leak outside. The structure reaches the lower side of the magnetocaloric material 11. In order to make the magnetocaloric material 11 into a plurality of layers, the permanent magnet 100, the yoke 101, and the magnetocaloric material 11 therebetween are stacked as a set. Thereby, each magnetocaloric material 11 can apply magnetism from the upper and lower sides.

  Comparing the configuration of the second embodiment and the laminated form with yoke, in the second embodiment, as already described, the magnet structure and the magnetocaloric material are alternately laminated. In addition, since a plurality of permanent magnets having a Halbach array are used for the magnet structures 21 and 25, there is little leakage of magnetic flux, which is almost the same as when a yoke is used (as described above).

  On the other hand, in the laminated form with a yoke, a yoke is necessary to apply magnetism to the magnetocaloric material 11 from above and below in the lamination direction. Therefore, the permanent magnet 100 is provided on the magnetocaloric material 11 for each layer, and the yoke 101 is disposed below. For this reason, in the laminated form with a yoke, a permanent magnet and a yoke exist between the magnetocaloric materials 11 in the laminating direction.

  As described above, in the second embodiment, only the permanent magnet is provided between the magnetocaloric materials 11 in the stacking direction, whereas in the stacked form with the yoke, there is a yoke. Therefore, since the yoke does not exist, Embodiment 2 can reduce the thickness of the entire magnetic heating device.

  Further, as shown in FIG. 15, the yoke must be protruded to the side of the magnetocaloric material 11. On the other hand, in the second embodiment, since such a protrusion is not required on the side of the magnetocaloric material 11, the diameter direction can be reduced.

  From these facts, when configured to be able to apply the same level of magnetism, the second embodiment can be reduced in size by about 20% compared to the case where the yoke is used. Since such a heavy object is not disposed, the weight can be reduced.

  The number of magnetocaloric materials may be more or less than that shown in the second embodiment in both the column direction and the layer direction. These may be determined according to the desired cooling / heating capacity and the heat generation, heat absorption, etc. of the magnetocaloric material.

  The effects of the embodiment described above will be described.

  (1) In this embodiment, in a state where magnetism is applied to the magnetocaloric material, a pair of magnet structures are arranged with the magnetocaloric material interposed therebetween. This magnet structure is composed of a plurality of permanent magnets having a Halbach arrangement with different magnetization directions, and the direction of the magnetic lines of force in the pair of magnet structures is in between (that is, the portion where the magnetocaloric material is disposed). Both are in the same direction. Thereby, since the magnetic force which acts between a pair of magnet structures becomes the same direction, stronger magnetism (magnetic field) can be applied to the magnetocaloric material in between. Moreover, since the magnetism (magnetic field) of the paired magnet structures can be made to act on the magnetocaloric material disposed between them, the efficiency of using the permanent magnet for the magnetocaloric material is very good. Become.

  In particular, as in the second embodiment, when a plurality of magnetocaloric materials are stacked, the magnetocaloric material can always be arranged between the magnet structures positioned above and below the magnetocaloric material. In such an arrangement, if attention is paid to the magnet structure between the magnetocaloric materials, the magnetocaloric material comes above and below, and the utilization efficiency of the permanent magnets constituting the magnet structure is further increased. It is what.

  (2) In the present embodiment, one magnet structure is composed of a plurality of permanent magnets, and the plurality of permanent magnets are arranged so as to gradually change until the respective magnetization directions become 180 degrees. With a plurality of permanent magnets arranged in such a Halbach arrangement, the magnet structure can form a strong magnetic field in a specific direction, here above or below the magnet structure, and is arranged between a pair of magnet structures. A strong magnetism can be applied to the generated magnetocaloric material, and a strong magnetic field generated by the magnetic circuit can be efficiently applied to the magnetocaloric material.

  (3) In this embodiment, a plurality of permanent magnets arranged so as to gradually change until the direction of magnetization reaches 180 degrees is set as one set, and at least one set of the plurality of permanent magnets used as one set is used. ing. Therefore, it is possible to apply strong magnetism to the magnetocaloric material disposed between the pair of magnet structures with only one set of permanent magnets. Then, by using a plurality of sets, the size of the magnet structure can be matched to various sizes of magnetocaloric materials.

  (4) In this embodiment, members made of a soft magnetic material are further provided at both ends of the magnet structure. Thereby, the direction of the magnetic field formed by the magnet structure can be directed to a more specific direction. Here, a magnetic field can be formed in the direction above or below the magnet structure.

  (5) In the present embodiment, a magnet structure, a magnetocaloric material, a magnet structure, a magnetocaloric material,... Are stacked so as to be a magnet structure, and the magnet structure between the magnetocaloric materials is The magnetism is applied to the magnetocaloric material located on the opposite side to the magnetocaloric material located on one side of the magnet structure. As described above, in this embodiment, there is a magnet structure between the magnetocaloric material and the magnetocaloric material, and strong magnetism can be applied to the magnetocaloric material without a yoke. Therefore, the size and weight can be reduced as compared with the case where the yoke structure is provided.

  Although the embodiment to which the present invention is applied has been described above, the present invention may have a configuration other than the embodiment described herein, and the present invention is various modifications defined by matters defined by the claims. Needless to say, this is possible.

11-18 magnetocaloric material,
20 substrates,
21-28 magnet structure,
30-33 thermal switch,
50 soft magnetic members,
201-208 Permanent magnet.

Claims (5)

A plurality of magnetocaloric materials arranged in rows at intervals and changing in temperature by applying and removing magnetism;
A magnetic circuit for applying and removing magnetism to each of the plurality of magnetocaloric materials;
Have
The magnetic circuit is:
In a state in which magnetism is applied to the magnetocaloric material, the magnetocaloric material comprises a pair of magnet structures with the magnetocaloric material sandwiched therebetween,
The magnet structure is composed of a plurality of permanent magnets having a Halbach array with different magnetization directions,
The direction of the magnetic force line formed by the said magnet structure is a magnetic air-conditioning / heating apparatus characterized by both the said pair of magnet structures being the same direction between the said pair of magnet structures.   The magnetic air conditioner according to claim 1, wherein the plurality of permanent magnets are arranged so as to gradually change until the direction of magnetization thereof reaches 180 degrees.   The plurality of permanent magnets arranged so as to gradually change until the magnetization direction reaches 180 degrees as one set, and the magnet structure uses at least one set of the plurality of permanent magnets. The magnetic air conditioner according to claim 2, wherein   The magnetic air conditioner according to any one of claims 1 to 3, further comprising a member made of a soft magnetic material at both ends of the magnet structure.   The magnet structure, the magnetocaloric material, the magnet structure, the magnetocaloric material,... Are stacked so as to be the magnet structure, and the magnet structure between the magnetocaloric materials is the magnet. The magnetic air conditioner according to any one of claims 1 to 4, wherein magnetism is applied to a magnetocaloric material located on the opposite side of the magnetocaloric material located on one side of the structure.