JP2010151407A - Magnetic refrigerating device and magnetic refrigerating system - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a magnetic refrigerating device and system, reducing input power by reducing power sources and improving refrigerating efficiency. <P>SOLUTION: This magnetic refrigerating device and system is provided with: a heat exchange container filled with magnetic particles having magnetocaloric effect; a magnetic field applying/removing mechanism for applying and removing magnetic field to the magnetic particles by relative motion of magnet and the heat exchange container; a low temperature side heat exchange part disposed at one end side of the heat exchange container; a high temperature side heat exchange part disposed at the other end side of the heat exchange container; and a liquid refrigerant moving mechanism forming a heat transport refrigerant flow flowing from one end side to the other end side or in the reverse direction in the heat exchange container by mechanically transmitting positional change of the magnet or the heat exchange container. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a magnetic refrigeration device and a magnetic refrigeration system using magnetic particles having a magnetocaloric effect.

Currently, most of refrigeration technologies in the room temperature range, which are closely related to human daily life, such as refrigerators, freezers, indoor air-conditioners, etc., use gas compression / expansion cycles. However, regarding refrigeration technology based on a gas compression / expansion cycle, environmental destruction associated with environmental discharge of specific chlorofluorocarbon gas is a major problem. Furthermore, there are concerns about the environmental impact of alternative chlorofluorocarbons. Therefore, recently, improvements using natural refrigerants (such as CO ₂ ) and isobutane are being carried out. Against this background, there is a demand for the practical use of a clean and highly efficient refrigeration technique that does not have the problem of environmental destruction associated with the disposal of working gas.

  In recent years, as one of such environmentally friendly and highly efficient refrigeration technologies, expectations for magnetic refrigeration have increased, and research and development of magnetic refrigeration technologies for room temperature regions have become active. In 1881, Warburg found a magnetocaloric effect in iron (Fe). The magnetocaloric effect is a phenomenon in which, when an externally applied magnetic field is changed with respect to a magnetic substance in an adiabatic state, the temperature of the magnetic substance changes.

  In magnetic refrigeration, a low temperature is generated as follows using the magnetocaloric effect. In a magnetic substance, entropy changes due to the difference in the degree of freedom of the electron magnetic spin system between a state when a magnetic field is applied and a state when a magnetic field is removed. With such entropy change, entropy shift occurs between the electron magnetic spin system and the lattice system. Magnetic refrigeration uses a magnetic material with a large electron magnetic spin. The entropy is transferred between the electron magnetic spin system and the lattice system to generate a low temperature by using a large entropy change between when the magnetic field is applied and when the magnetic field is removed.

In the first half of the 1900s, paramagnetic salts such as Gd ₂ (SO ₄ ) ₃ .8H ₂ O and Gd ₃ Ga ₅ O ₁₂ (gadolinium gallium garnet; GGG) are represented as magnetic refrigeration working substances having a magnetocaloric effect. Refrigeration devices using paramagnetic compounds have been developed. The refrigeration device that realizes magnetic refrigeration using paramagnetic substances is mainly applied to the cryogenic region below 20K, and uses a magnetic field of about 10 Tesla that can be obtained using a superconducting magnet. Yes.

On the other hand, in order to realize magnetic refrigeration at higher temperatures, research on magnetic refrigeration using a magnetic phase transition between a paramagnetic state and a ferromagnetic state in ferromagnetic materials has been actively conducted since the 1970s. . And lanthanum series rare earth elements such as Pr, Nd, Dy, Er, Tm, Gd, or two or more rare earth alloy materials such as Gd-Y, Gd-Dy, RAl ₂ (R represents a rare earth element) , The same applies hereinafter), and many magnetic materials containing rare earths having a large electron magnetic spin per unit volume, such as rare earth intermetallic compounds such as RNi ₂ and GdPd.

  In 1974, Brown in the United States realized magnetic refrigeration at room temperature for the first time using a ferromagnetic material Gd having a ferromagnetic phase transition temperature (Tc) of about 294K. However, in Brown's experiment, although the refrigeration cycle was operated continuously, it did not reach a steady state. In 1982, Barclay in the United States devised the active use of lattice entropy, which had been positioned as an impediment to magnetic refrigeration at room temperature. In addition, a refrigeration system that simultaneously bears the heat storage effect of storing the cold generated by the magnetic refrigeration work has been proposed (see Patent Document 1). This magnetic refrigeration system is called an AMR (Active Magnetic Refrigeration) system. Both of these refrigeration devices operate under a strong magnetic field using a superconducting magnet.

  In 1997, Zim, Gschneidner, Pecharsky et al. Of the United States made a prototype of an AMR type magnetic refrigeration device using a filled cylinder filled with fine spherical Gd, and succeeded in continuous steady operation of the magnetic refrigeration cycle at room temperature. . According to this, by changing the magnetic field from 0 Tesla to 5 Tesla by using a superconducting magnet in the room temperature range, when the freezing temperature difference (ΔT) is 13 ° C. It has been reported that very high refrigeration efficiency (COP = 15; except for the input power to the magnetic field generating means) was obtained. Incidentally, the COP (Coefficient of Performance: coefficient of performance) of a household refrigerator or the like in a compression cycle using conventional chlorofluorocarbon is about 1 to 3.

  In 2000, there was a report using permanent magnets at Bohigas et al. In Spain. This is a structure in which a magnetic refrigeration working material with a rotational drive system is inserted into a gap between fixed opposing permanent magnets. Using Gd as a magnetic refrigeration work substance, cooling at 1.5 ° C. has been demonstrated in a room temperature environment under the conditions of magnetic field strength: 0.3 T, refrigerant: olive oil, rotation speed: 4-50 rpm.

  Since then, room temperature refrigeration technology using permanent magnets has been actively developed. The magnetic field application / removal means is roughly classified into a rotary type and a reciprocating type. The rotation type is a method in which a magnet moves in a rotation direction with respect to a fixed magnetic refrigeration working material. On the other hand, the reciprocating type is a system in which a magnetic circuit that generates a magnetic field and a magnetic refrigeration material relatively reciprocate.

In order to obtain an AMR type magnetic refrigeration cycle regardless of the rotary type or the reciprocating type, magnetic field ON → refrigerant movement to the high temperature side → magnetic field OFF → refrigerant movement to the low temperature end is repeated. Therefore, in the AMR type magnetic refrigeration device, conventionally, the power source for applying and removing the magnetic field, the power source for moving the refrigerant, and the timing of the magnetic refrigeration cycle are intended to synchronize the magnetic field applying and removing mechanism and the refrigerant moving mechanism. A control circuit was used.
US Pat. No. 4,332,135

  However, when two power sources are used in the magnetic field application removal mechanism and the refrigerant moving mechanism, there is a problem that the operation input power of the magnetic refrigeration device is increased and the refrigeration efficiency is lowered. Here, the refrigeration efficiency is represented by COP, and there is a relationship of actual COP = refrigeration capacity W / input power W. In order to improve the refrigeration efficiency of the magnetic refrigeration device, it is necessary to reduce the input power for obtaining a constant refrigeration capacity.

  The present invention has been made in view of the above circumstances, and an object of the present invention is to provide a magnetic refrigeration device and a magnetic refrigeration system that reduce input power by reducing the power source and improve refrigeration efficiency. There is to do.

  A magnetic refrigeration device according to an aspect of the present invention includes a heat exchange container filled with magnetic particles having a magnetocaloric effect, and applying and removing a magnetic field to and from the magnetic particles relative to the magnet and the heat exchange container. A magnetic field application removal mechanism realized by movement, a low temperature side heat exchange part provided on one end side of the heat exchange container, a high temperature side heat exchange part provided on the other end side of the heat exchange container, the magnet or the heat A liquid refrigerant moving mechanism that forms a heat transport refrigerant flow that flows in the heat exchange container from the one end side to the other end side or in the opposite direction by mechanically transmitting a change in position of the exchange container. It is characterized by.

  In the magnetic refrigeration device according to the above aspect, the liquid refrigerant moving mechanism generates pressure in conjunction with a piston provided at both ends of the heat exchange container and moving the liquid refrigerant, and a position change of the magnet or the heat exchange container. It is desirable to provide a pressure generator and a pressure pipe that transmits the pressure generated by the pressure generator to the piston.

  In the magnetic refrigeration device of the above aspect, it is desirable that a pressure on-off valve that interlocks opening and closing of the valve with a change in position of the magnet or the heat exchange container is provided in the pressure pipe.

  In the magnetic refrigeration device according to the above aspect, it is desirable that the magnet and the heat exchange container relatively linearly move.

  In the magnetic refrigeration device according to the above aspect, the magnet and the heat exchange container relatively rotate, and the liquid refrigerant moving mechanism converts the rotational movement of the magnet or the heat exchange container into a linear motion. It is desirable to have

  In the magnetic refrigeration device of the above aspect, the magnetic field application / removal mechanism includes a plurality of power sources, a cooling / freezing state monitoring unit that monitors a cooling / freezing state of the heat exchange vessel, and a monitor by the cooling / freezing state monitoring unit It is desirable to have a power source switching unit that switches the power source according to the result.

  In the magnetic refrigeration device of the above aspect, it is desirable to use mechanical energy by wave force, wind force or hydraulic power as a power source of the magnetic field application removal mechanism.

  The magnetic refrigeration system according to one aspect of the present invention includes the magnetic refrigeration device according to the above aspect, a cooling unit that is thermally connected to the low temperature side heat exchange unit, and an exhaust that is thermally connected to the high temperature side heat exchange unit. And a heating part.

  According to the present invention, it is possible to provide a magnetic refrigeration device and a magnetic refrigeration system that reduce input power by reducing power sources and improve refrigeration efficiency.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings.

(First embodiment)
The magnetic refrigeration device according to the first embodiment of the present invention includes a heat exchange container filled with magnetic particles having a magnetocaloric effect, and application and removal of a magnetic field to these magnetic particles to exchange heat with a magnet. Magnetic field application removal mechanism realized by relative movement with the container, a low temperature side heat exchange part provided on one end side of the heat exchange container, a high temperature side heat exchange part provided on the other end side of the heat exchange container, and a magnet Alternatively, a liquid refrigerant moving mechanism that forms a heat transport refrigerant flow that flows in the heat exchange container from one end side to the other end side or in the opposite direction by mechanically transmitting the position change of the heat exchange container.

  Here, mechanically transmitting means that mechanical energy is transmitted as mechanical energy without being converted into another energy form such as electric energy.

  FIG. 1 is a schematic structural cross-sectional view of the magnetic refrigeration device of the present embodiment. In the magnetic refrigeration device 10, magnetic particles 12 having a magnetocaloric effect are filled in a heat exchange container 14 using, for example, a mesh-like partition plate.

  And the magnetic field application removal mechanism 20 is provided. This magnetic field application removal mechanism 20 has permanent magnets (hereinafter also simply referred to as magnets) 16a and 16b, and a power source 18 that drives the permanent magnets 16a and 16b in the direction of the black arrow in the figure. The magnetic field application removal mechanism 20 enables application and removal of a magnetic field to the magnetic particles 12 in the heat exchange container 14 by relative movement between the magnets 16 a and 16 b and the heat exchange container 14.

  As the permanent magnets 16a and 16b, for example, NdFeB magnets, SmCo magnets, ferrite magnets, and the like can be applied. The magnets 16a and 16b are arranged in a U shape, a cylindrical shape, a Halbach type or the like, and the magnets 16a and 16b and a magnetic yoke (not shown) are used for effective and high efficiency of a magnetic flux return path. The magnetic circuit is formed.

  The magnetic refrigeration device 10 is connected to the pipe 30 on the other end side of the low-temperature side heat exchanging unit 22 provided on one end side in the heat exchange container 14 and connected to the pipe 30 on the other end side of the heat exchange container 14. The high temperature side heat exchange part 24 provided is provided. Here, the low temperature side heat exchanging unit 22 can have a function of exchanging cold with the outside of the device. The high temperature side heat exchanging unit 24 can have a function of exchanging high heat with the outside of the device.

  And this magnetic refrigeration device 10 flows in the direction of the high temperature side heat exchange part 24 or the reverse direction from the low temperature side heat exchange part 22 through the inside of the heat exchange container 14 as shown by the white arrow in the figure. A liquid refrigerant moving mechanism 26 that forms a heat transport refrigerant flow is provided. The liquid refrigerant moving mechanism 26 forms a heat transport refrigerant flow by mechanically transmitting a relative positional change between the magnets 16a and 16b and the heat exchange container 14 indicated by black arrows in the drawing.

  Here, a case where the heat exchange container 14 is fixed and the positions of the magnets 16a and 16b change will be described as an example. This bidirectional heat transport refrigerant flow is synchronized with the application and removal of the magnetic field to the magnetic particles 12 by the magnetic field application and removal mechanism 20.

  The heat exchange container 14, the low temperature side heat exchange unit 22, and the high temperature side heat exchange unit 24 are connected to each other by a pipe 30 through which a liquid refrigerant, for example, an ethylene glycol aqueous solution is passed, to form a refrigerant circuit in which the refrigerant circulates. A new power source other than the power source 18 for moving and circulating the liquid refrigerant is not provided.

  In the magnetic refrigeration device 10 of the present embodiment, the heat exchange container 14 is filled with magnetic particles 12 such as Gd (gadolinium) having a magnetocaloric effect. Then, when the permanent magnets 16a and 16b are opposed to the magnetic particles 12, the magnetic particles generate heat. This thermal energy is moved to the high temperature side heat exchanging unit 24 side by the heat transport refrigerant flow generated by the liquid refrigerant moving mechanism 26.

  The magnetic particles 12 absorb heat by moving the permanent magnets 16a and 16b away from the magnetic particles 12 by the magnetic field application / removal mechanism 20 using the power source 18. This heat energy is moved to the low-temperature side heat exchanging part 22 side in the reverse direction by the heat transport refrigerant flow generated by the liquid refrigerant moving mechanism 26. By repeating this operation (hereinafter referred to as a magnetic refrigeration cycle), a temperature gradient is generated in the heat exchange vessel 14 due to the heat storage effect of the magnetic particles 12, and the cold heat is high on the low temperature side heat exchange section 22 side. High heat can be obtained on the side heat exchange section 24 side.

  In the magnetic refrigeration device 10, the position change of the magnets 16 a and 16 b is mechanically transmitted to form a heat transport refrigerant flow. That is, the movement of the magnets 16 a and 16 b and the liquid refrigerant is executed by one power source 18.

  FIG. 2 is a schematic structural cross-sectional view of the main part of the magnetic refrigeration device of the present embodiment. FIG. 2 particularly shows the power transmission mechanism of the liquid refrigerant moving mechanism 26 of FIG. 1 in detail. First, the magnets 16a and 16b are supported by the magnet support members 32a and 32b so as to be movable in the vertical direction in the figure with respect to the heat exchange container.

  Further, a power transmission plate 34 is attached to the magnet support member 32b. The power transmission plate 34 transmits the positional changes of the magnets 16a and 16b and the magnet support members 32a and 32b to the liquid refrigerant.

  The magnetic refrigeration device 10 includes a pressure pipe 36 for transmitting the position changes of the magnets 16a and 16b and the magnet support members 32a and 32b to the liquid refrigerant. The low temperature end side piston 38 on the low temperature end side, the low temperature end side pressure generator 40, the high temperature end side pressure generator 42, and the high temperature end side high temperature end side piston 44 are connected via the pressure pipe 36. ing.

  The low temperature end side piston 38 and the high temperature end side piston 44 have a piston structure for moving the liquid refrigerant filled in the heat exchange container 14. A flow path 30a that leads from the low temperature end side piston 38 to the low temperature side heat exchange part 22 (FIG. 1), and a flow path 30b that leads from the high temperature end side piston 44 to the high temperature side heat exchange part 24 (FIG. 1) Is provided. The low temperature end side pressure generator 40 and the high temperature end side pressure generator 42 have a piston structure for transmitting pressure to the air in the pressure pipe 36.

  And the low temperature end side pressure on-off valve 50 and the high temperature end side pressure on / off valve 52 are being fixed to the fixed ends 48a and 48b, respectively. The low temperature end side pressure on / off valve 50 and the high temperature end side pressure on / off valve 52 are also connected to the pressure pipe 36. The opening and closing of the valve is interlocked with the change in position of the magnets 16a and 16b, so that the flow of the liquid refrigerant is synchronized with the application and removal of the magnetic field to the magnetic particles 12 by the magnetic field application and removal mechanism 20. .

  FIG. 3 is a cross-sectional view of a two-stage pressure on / off valve used for the low temperature end side pressure on / off valve 50 and the high temperature end side pressure on / off valve 52. Two pressure on-off valves, that is, an open valve 56 and a pressure valve 58 are attached to the base 54.

  Pistons 56a and 58a are provided in the cylinders in the release valve 56 and the pressure valve 58 so as to be slidable. Through holes 56b and 58b are provided in the pistons 56a and 58a. Air pipes 56c and 58c connected to the pressure pipe 36 are provided on the side surface of the cylinder, and springs 56d and 58d are provided between the cylinder base 54 side and the pistons 56a and 58a.

  An operating plate 59 is connected to both the pistons 56a and 58a. When the operating plate 59 moves, the pistons 56a and 58a move, and when the through holes 56b and 58b are aligned with the air pipes 56c and 58c connected to the pressure pipe 36 (FIG. 2), the valve is opened. It becomes the structure which becomes.

  The positions of the air pipe 56c and the air pipe 58c differ from each other by a certain distance d as shown in the figure. Therefore, in this two-stage pressure on-off valve, when the operating plate 59 is pushed in, the opening valve 56 is first opened, and the pressure valve 58 is opened after a predetermined delay time. have. In the present embodiment, open ends 36 a and 36 b (FIG. 2) for releasing the pressure of air in the pressure pipe 36 are connected to a portion corresponding to one end of the air pipe 56 c of the open valve 56.

  Next, an operation procedure according to the magnetic refrigeration cycle of the magnetic refrigeration device 10 will be described. 4-8 is explanatory drawing of the operation | movement procedure of the magnetic refrigeration device of this Embodiment.

  The position in FIG. 4 is defined as the start of the magnetic refrigeration cycle. The permanent magnets 16 a and 16 b move linearly by the power source 18 and move to the low temperature end side of the heat exchange vessel 14. Along with this, the power transmission plate 34 also rises and starts pushing the piston of the low temperature end side pressure generator 40. In the state of FIG. 4, all of the low temperature end side pressure on / off valve 50 and the high temperature end side pressure on / off valve 52 are closed.

  Furthermore, as shown in FIG. 5, the permanent magnets 16 a and 16 b move to the low temperature end side of the heat exchange container 14. As a result, a magnetic field is applied to the magnetic particles 12 and the magnetic particles 12 start to generate heat.

  The magnet support member 32a comes into contact with the low-temperature end-side pressure on / off valve 50. First, the open valve is opened, and the pressure pipe 36 is opened at the open end 36a. When the permanent magnets 16a and 16b further move to the low temperature end side of the heat exchange vessel 14, the pressure valve of the low temperature end side pressure opening / closing valve 50 is opened after a predetermined delay time.

  Then, the pressure applied to the air in the pressure pipe 36 by the low temperature end side pressure generator 40 passes through the pressure pipe 36 of the open low temperature end side pressure open / close valve 50 through the pressure pipe 36 as indicated by the black arrow. Then, the piston of the low temperature end side piston 38 is pushed to move the liquid refrigerant from the low temperature end side to the high temperature end side of the heat exchange vessel 14. Then, the liquid refrigerant flows through the flow path 30b to the high temperature side heat exchange unit 24 (FIG. 1).

  Next, as shown in FIG. 6, the permanent magnets 16 a and 16 b start moving to the high temperature end side of the heat exchange container 14. As a result, the magnetic field begins to be removed from the magnetic particles 12 and the magnetic particles 12 start to absorb heat. Then, both the pressure valve and the open valve of the low temperature end side pressure open / close valve 50 are closed.

  Next, as shown in FIG. 7, the permanent magnets 16 a and 16 b further move to the high temperature end side of the heat exchange container 14. Thereby, the magnetic field is almost removed from the magnetic particles 12. The power transmission plate 34 is also lowered and starts to push the piston of the high temperature end side pressure generator 42.

  Further, as shown in FIG. 8, when the permanent magnets 16 a and 16 b move to the high temperature end side of the heat exchange vessel 14, the power transmission plate 34 comes into contact with the high temperature end side pressure open / close valve 52. First, the release valve is opened, and the pressure pipe 36 is opened at the open end 36b. When the permanent magnets 16a and 16b further move to the high temperature end side of the heat exchange vessel 14, the pressure valve of the high temperature end side pressure on / off valve 52 is opened after a predetermined delay time.

  Then, the pressure applied to the air in the pressure pipe 36 by the high temperature end side pressure generator 42 passes through the pressure pipe 36 through the pressure valve of the opened high temperature end side pressure open / close valve 52 as shown by the black arrow. Then, the piston of the high temperature end side piston 44 is pushed to move the liquid refrigerant from the high temperature end side to the low temperature end side of the heat exchange container 14. Then, the liquid refrigerant flows through the flow path 30a to the low temperature side heat exchange unit 22 (FIG. 1).

  After returning to the position shown in FIG. 4 through the above operation, a magnetic refrigeration cycle is realized by repeating these operations.

  As described above, according to the present embodiment, the change in position of the magnet of the magnetic field application / removal mechanism is mechanically transmitted to the pressure generator of the liquid refrigerant moving mechanism, so that an independent actuator or pump for moving the refrigerant can be used. No power source is required. Therefore, the input power required for moving the refrigerant is reduced, and a high COP can be realized.

  Also, by transmitting the position change of the magnet of the magnetic field application / removal mechanism mechanically to the pressure on / off valve, after applying or removing the magnetic field to / from the magnetic particles, the heat exchange container at the high temperature end side or low temperature The refrigerant can move to the end side. Therefore, there is no need for a position monitor or a control circuit that measures the timing of the magnetic refrigeration cycle. Therefore, simplification of the device and further improvement of COP can be realized.

  In addition, it is not always essential that the pressure pipe is provided with a pressure on / off valve that is linked to the change in position of the magnet or the heat exchange container. Even if a position monitor, a control circuit, or the like for measuring the timing of the magnetic refrigeration cycle is separately provided, a high COP can be realized by eliminating the need for a power source such as an independent actuator or a pump for moving the refrigerant.

  In addition, natural mechanical energy such as wave power, wind power, hydraulic power or geothermal steam is directly used as mechanical energy for the power source of the magnetic field application / removal mechanism of the present embodiment without converting it into electrical energy. It is desirable. This is because there is no energy loss due to electrical conversion, and further improvement of COP can be realized.

  In the present embodiment, the position of the magnet is changed. However, the position of the heat exchange container may be changed with the magnet fixed.

The magnetic particles having the magnetocaloric effect of the present embodiment are not particularly limited. For example, Gd compounds in which various elements are mixed with Gd (gadolinium), intermetallic compounds composed of various rare earth elements and transition metal elements, Ni ₂ MnGa, and the like as long as the magnetic particles exhibit a magnetocaloric effect. Magnetic particles such as alloys, GdGeSi compounds, LaFe ₁₃ compounds, LaFe ₁₃ H, and the like can be used.

  The magnetic particles are preferably substantially spherical and have an average particle diameter of 100 μmΦ to 2000 μmΦ. The measurement of the average particle diameter of the magnetic particles can be evaluated by vernier calipers or the like under visual observation, or by direct observation under a microscope or measurement with a micrograph.

  To reduce the pressure loss, increase the surface area, and increase the heat exchange efficiency, a substantially spherical shape is suitable. Further, if the average particle diameter is smaller than this range, the pressure loss is remarkably increased, the movement of the heat transport refrigerant is hindered, and the refrigeration efficiency of the magnetic refrigeration device may be lowered. Further, if it exceeds this range, the surface area becomes small and the amount of refrigerant involved in heat transport becomes extremely small, so that the effect of improving the heat exchange efficiency of the present embodiment is hardly exhibited.

  From the viewpoint of reducing the pressure loss and improving the heat exchange efficiency, the aspect ratio of the magnetic particles of 80 wt% or more is 2 or less, and the magnetic particle diameter (major axis) is 100 μmΦ or more and 2000 μmΦ or less. desirable.

  Further, from the viewpoint of further increasing the freezing temperature difference (ΔTspan), the average particle diameter is more preferably 200 μmΦ to 800 μmΦ. The definition of the freezing temperature difference (ΔTspan) is the temperature difference between the high temperature end temperature and the low temperature end temperature.

  The volume filling rate of the magnetic particles in the heat exchange container is desirably 40% or more and 70% or less. This is because if the temperature falls below the above range, the refrigeration temperature difference (ΔTspan) is significantly reduced due to a decrease in the heat exchange area. Further, when the value is below the above range, magnetic particles caused by magnetic field removal due to application and removal of the magnetic field and vibration / collision of the magnetic particles due to the flow of the refrigerant occur, so that fine powder is generated and pressure loss is likely to occur. Moreover, if it exceeds the said range, it is because a freezing temperature difference ((DELTA) Tspan) will decrease by the increase in pressure loss. The volume filling rate is more preferably 50% or more and 65% or less.

  As a refrigerant, water is suitable because it has the highest specific heat and is inexpensive, but in a temperature range of 0 ° C. or lower, an oil-based refrigerant such as mineral oil or silicon, a solvent system such as an antifreeze, alcohol such as ethylene glycol, or the like. A refrigerant can also be used.

  The oil-based refrigerant, solvent-based refrigerant, water, a mixed solution thereof, and the like described above can be appropriately selected according to the operating temperature range of the refrigeration cycle. As for the average particle size of the magnetic particles, it is desirable to select an optimal particle size within the above range according to the viscosity (surface tension) of the refrigerant used and the size of the heat exchange container.

(Second Embodiment)
In the magnetic refrigeration device according to the second embodiment of the present invention, the magnetic field application / removal mechanism has a plurality of power sources, a cold / freezer state monitor unit for monitoring the cold / frozen state of the heat exchange container, and a cold / frozen state monitor. A power source switching unit that switches a plurality of power sources according to the monitoring result of the unit. Except for having a plurality of power sources, a cold / refrigeration state monitoring unit, and a power source switching unit, it is the same as in the first embodiment, and therefore, the description of the overlapping contents is omitted.

  FIG. 9 is a schematic structural cross-sectional view of the main part of the magnetic refrigeration device of the present embodiment. As shown in the figure, the magnetic field application removal mechanism includes a first power source 60 and a second power source 62. Moreover, these power sources are connected and the power source switching part 64 which switches two power sources is provided.

  Furthermore, a cooling / freezing state monitoring unit 66 for monitoring the cooling / freezing state of the heat exchange container 14 is provided. Further, it has a power source control circuit 68 that receives the monitoring result from the cold / freezing state monitoring unit 66 as a signal and controls the power source switching unit 64.

  Here, the first power source 60 uses, for example, mechanical energy in nature, for example, wave power, wind power, hydraulic power or geothermal steam as mechanical energy as it is without converting it into electrical energy. The second power source 62 is, for example, an internal combustion engine or an actuator that moves linearly converted from electric energy.

  According to the magnetic refrigeration device of the present embodiment, for example, when the first power source 60 using unstable natural mechanical energy alone does not stabilize the cold / refrigerated state, the power source is used as the second power source. By switching to the source 62, a stable cold / refrigerated state can be maintained. Therefore, it is possible to exhibit a stable refrigerating capacity while directly using natural mechanical energy to reduce input power and improve COP.

(Third embodiment)
In the magnetic refrigeration device according to the third embodiment of the present invention, the magnet or the heat exchange container relatively rotates, and the liquid refrigerant moving mechanism moves the rotation of the magnet or the heat exchange container into a linear motion. It has a conversion part. Since the magnet or the heat exchange container is the same as in the first embodiment except that the magnet or the heat exchange container performs a rotational motion rather than a linear motion and has a motion direction conversion unit, the description of the overlapping contents is omitted.

  FIG. 10 is a schematic structural cross-sectional view of the main part of the magnetic refrigeration device of the present embodiment. 11 is a cross-sectional view taken along line AA in FIG. 12 is a cross-sectional view taken along the line BB in FIG. FIG. 13 is a top view of FIG.

  This magnetic refrigeration device includes magnets 70a, b, c, and d, a magnet support plate 72a that supports the magnets 70a and c, and a magnet support plate 72b that supports the magnets 70b and d. The magnets 70a to 70d are configured to be rotatable with respect to the heat exchange containers 78a and 78b by the power source 76 with the rotation shaft 74 as a center.

  As shown in FIG. 11, the low temperature end side pistons 80a, 80b are connected to the low temperature end side of the heat exchange containers 78a, 78b, and the high temperature end side pistons 82a, 82b are connected to the high temperature end side. The low temperature end side pistons 80a, 80b are connected to a low temperature end side pressure generator (not shown) by pressure piping. The high temperature end side pistons 82a and 82b are connected to a high temperature end side pressure generator (not shown) by pressure piping.

  The low temperature end side pistons 80a, 80b and the high temperature end side pistons 82a, 82b have a piston structure for moving the liquid refrigerant filled in the heat exchange containers 78a, 78b. Then, the flow paths 84a, b leading from the low temperature end side pistons 80a, 80b to the low temperature side heat exchange part (not shown) are connected to the high temperature side heat exchange part (not shown) from the high temperature end side pistons 82a, b. Channels 86a and 86b that communicate with each other are provided.

  Furthermore, as shown in FIG. 13, a motion direction conversion unit 88 is provided. The movement direction conversion unit 88 converts, for example, the rotational movement of the magnet support plate 72a into a linear movement using an eccentric mechanism such as a crankshaft. Using this linear motion, as in the first embodiment, the liquid refrigerant mechanism is operated to move the liquid refrigerant.

  In addition, it is desirable to use an eccentric mechanism such as a crankshaft from the viewpoint of conversion efficiency and ease of structure for conversion from rotational motion to linear motion. However, for example, a mechanism using a planetary gear or a ball screw may be used.

  According to the present embodiment, similarly to the first embodiment, it is possible to realize a magnetic refrigeration device with improved COP by reducing the number of power sources. Furthermore, it is desirable to use wind power or hydraulic power, which is mechanical energy in the natural world that can be easily converted into rotational motion, as the power source of the present embodiment, because it is possible to further improve COP.

(Fourth embodiment)
A magnetic refrigeration system according to a fourth embodiment of the present invention includes a magnetic refrigeration device according to the first to third embodiments, a cooling unit thermally connected to a low-temperature side heat exchange unit, and a high temperature And an exhaust heat unit thermally connected to the side heat exchange unit. Hereinafter, the description overlapping with the contents described in the first to third embodiments is omitted.

  FIG. 14 is a schematic structural cross-sectional view of the magnetic refrigeration system of the present embodiment. This magnetic refrigeration system includes a cooling unit 90 that is thermally connected to the low temperature side heat exchange unit 22 and a heat exhaust unit that is thermally connected to the high temperature side heat exchange unit 24 in addition to the magnetic refrigeration device 10 of FIG. 100.

  The low temperature side heat exchanging unit 22 includes a low temperature side reservoir 92 for storing a low temperature refrigerant, and a low temperature side heat exchanger 94 provided in contact with the refrigerant therein. Similarly, the high temperature side heat exchange unit 24 includes a high temperature side reservoir 102 that stores a high temperature refrigerant, and a high temperature side heat exchanger 104 that is provided in contact with the refrigerant inside. The cooling unit 90 is thermally connected to the low temperature side heat exchanger 22, and the exhaust heat unit 100 is thermally connected to the high temperature side heat exchanger 24.

  Here, this magnetic refrigeration system can be applied to a household refrigerator, for example. In this case, the cooling unit 90 is a freezing / refrigeration room that is an object to be cooled, and the exhaust heat unit 100 is, for example, a heat sink.

  Moreover, this magnetic refrigeration system can be applied to a freezer for fishing boats, for example. In this case, the cooling unit 90 is a freezer that is an object to be cooled, and the exhaust heat unit 100 is, for example, a heat sink. And it is preferable to use wave power as the power source 18. At this time, for example, a linear up-and-down movement by a wave of a float floating on the sea surface is used as the magnetic field removal applying mechanism. By using wave power, input power can be reduced and further COP improvement can be achieved.

  The magnetic refrigeration system is not particularly limited. In addition to the above-mentioned domestic refrigerator-freezers and fishing boat freezers, for example, it is applied to refrigeration systems such as household refrigerator-freezers, household air conditioners, industrial refrigerator-freezers, large-sized refrigerator-freezers, liquefied gas storage / transport refrigerators, etc. It is possible. The required refrigeration capacity and control temperature range differ depending on the application location. However, the refrigerating capacity can be varied according to the amount of magnetic particles used. Further, the control temperature range can be adjusted to a specific temperature range because the magnetic transition temperature can be varied by controlling the material of the magnetic particles. Furthermore, the present invention can also be applied to air conditioning systems such as home air conditioners and industrial air conditioners that use the exhaust heat of the magnetic refrigeration device as heating. You may apply to the plant using both cooling and heat_generation | fever.

  With the magnetic refrigeration system of the present embodiment, a magnetic refrigeration system that improves the magnetic refrigeration efficiency can be realized.

  The embodiments of the present invention have been described above with reference to specific examples. The above embodiment is merely given as an example and does not limit the present invention. Further, in the description of the embodiment, the description of the portions that are not directly necessary for the description of the present invention in the magnetic refrigeration device, the magnetic refrigeration system, etc. is omitted, but the required magnetic refrigeration device, the magnetic refrigeration system. It is possible to appropriately select and use elements related to the above.

  In addition, all magnetic refrigeration devices and magnetic refrigeration systems that include the elements of the present invention and whose design can be appropriately changed by those skilled in the art are included in the scope of the present invention. The scope of the present invention is defined by the appended claims and equivalents thereof.

It is a typical structure sectional view of the magnetic refrigeration device of a 1st embodiment. It is typical structure sectional drawing of the principal part of the magnetic refrigeration device of a 1st embodiment. It is sectional drawing of the two-stage pressure on-off valve of 1st Embodiment. It is explanatory drawing of the operation | movement procedure of the magnetic refrigeration device of 1st Embodiment. It is explanatory drawing of the operation | movement procedure of the magnetic refrigeration device of 1st Embodiment. It is explanatory drawing of the operation | movement procedure of the magnetic refrigeration device of 1st Embodiment. It is explanatory drawing of the operation | movement procedure of the magnetic refrigeration device of 1st Embodiment. It is explanatory drawing of the operation | movement procedure of the magnetic refrigeration device of 1st Embodiment. It is a typical structure sectional view of the important section of the magnetic refrigeration device of a 2nd embodiment. It is a typical structure sectional view of the important section of the magnetic refrigeration device of a 3rd embodiment. It is AA sectional drawing of FIG. It is BB sectional drawing of FIG. It is a top view of FIG. It is a typical structure sectional view of the magnetic refrigeration system of a 4th embodiment.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 Magnetic refrigeration device 12 Magnetic substance particle 14 Heat exchange container 16a, b Permanent magnet 18 Power source 20 Magnetic field application removal mechanism 22 Low temperature side heat exchange part 24 High temperature side heat exchange part 26 Liquid refrigerant moving mechanism 30 Piping 32a, b Magnet support member 34 Power transmission plate 36 Pressure pipe 38 Low temperature end side piston 40 Low temperature end side pressure generator 42 High temperature end side pressure generator 44 High temperature end side piston 48a, b Fixed end 50 Low temperature end side pressure on-off valve 52 High temperature end side pressure on / off valve 54 Pedestal 56 Opening valve 56a Piston 56b Through hole 56c Air pipe 58 Pressure valve 58a Piston 58b Through hole 58c Air pipe 59 Operating plate 60 First power source 62 Second power source 64 Power source switching unit 66 Cold / freezing state monitor Portion 68 Power source control circuit 70a-d Magnet 72a, b Magnet support plate 74 Rotating shaft 76 Power source 78a, b Heat exchange vessel 80 a, b Low temperature end side piston 82a, b High temperature end side piston 86a, b Flow path 88 Movement direction conversion part 90 Cooling part 92 Low temperature side reservoir 94 Low temperature side heat exchanger 100 Heat exhaust part 102 High temperature side reservoir 104 High temperature side Heat exchanger

Claims (8)

A heat exchange container filled with magnetic particles having a magnetocaloric effect;
A magnetic field application / removal mechanism for applying and removing a magnetic field to / from the magnetic particles by a relative motion of a magnet and the heat exchange vessel;
A low temperature side heat exchange section provided on one end side of the heat exchange vessel;
A high temperature side heat exchange section provided on the other end side of the heat exchange vessel;
A liquid refrigerant moving mechanism that forms a heat transport refrigerant flow that flows in the heat exchange container from the one end side to the other end side or in the opposite direction by mechanically transmitting a change in position of the magnet or the heat exchange container. When,
A magnetic refrigeration device comprising: The liquid refrigerant moving mechanism is
Pistons provided at both ends of the heat exchange container to move the liquid refrigerant;
A pressure generator that generates pressure in conjunction with a change in position of the magnet or the heat exchange vessel;
A pressure pipe for transmitting the pressure generated by the pressure generator to the piston;
The magnetic refrigeration device according to claim 1, comprising:   The magnetic refrigeration device according to claim 2, wherein the pressure pipe is provided with a pressure on / off valve that interlocks with a change in position of the magnet or the heat exchange container.   The magnetic refrigeration device according to any one of claims 1 to 3, wherein the magnet and the heat exchange container relatively linearly move.   The magnet and the heat exchange container relatively rotate, and the liquid refrigerant moving mechanism has a motion direction conversion unit that converts the rotational motion of the magnet or the heat exchange container into a linear motion. The magnetic refrigeration device according to any one of claims 1 to 4.   The magnetic field application removal mechanism includes a plurality of power sources, a cooling / freezing state monitoring unit that monitors a cooling / freezing state of the heat exchange container, and the power source according to a monitoring result by the cooling / freezing state monitoring unit. The magnetic refrigeration device according to any one of claims 1 to 5, further comprising a power source switching unit for switching.   The magnetic refrigeration device according to any one of claims 1 to 6, wherein mechanical energy generated by wave power, wind power, or hydraulic power is used as a power source of the magnetic field application removal mechanism. A magnetic refrigeration device according to any one of claims 1 to 7,
A cooling unit thermally connected to the low temperature side heat exchange unit;
An exhaust heat section thermally connected to the high temperature side heat exchange section;
A magnetic refrigeration system comprising:

Images