JPS63129268A - Rotary type magnetic refrigerator - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

[Detailed description of the invention] [Purpose of the invention] (Industrial application field) The present invention relates to a nine-rotation magnetic refrigeration device, and more particularly.

The present invention relates to a magnetic refrigeration device that can improve the efficiency of exhausting heat from working materials.

(Prior Art) Magnetic refrigeration devices that utilize the magnetocaloric effect of magnetic materials have been known. The magnetic cooler 21B condenses the gas to be condensed using a magnetic material that has been cooled by adiabatic demagnetization.9It has the advantage of higher refrigerating efficiency per unit volume than normal compression refrigerators. .

By the way, in the case of magnetic refrigeration equipment, magnetic materials such as gadolinium, gallium, and garnet are used.

In other words, the working material is rapidly introduced into the magnetic field to be adiabatically magnetized, and the heat generated in the working material is released to the outside through a heat exhaust process, and the working material located within the field is rapidly introduced outside the magnetic field. It is necessary to perform two heat exchange processes alternately: an endothermic process in which the gas is adiabatically demagnetized, and the gas to be condensed is condensed by the endothermic action at this time.

For this reason, in conventional magnetic refrigeration equipment, 2
A linear motion type that moves the work material back and forth in a straight line and positions the work material alternately inside and outside the magnetic field through this reciprocating motion, and a linear motion type that moves the work material along a circular orbit to move the work material along a circular orbit. A rotating type is considered in which the magnetic field is alternately positioned inside and outside the magnetic field. this house.

Since the rotating type can adopt a configuration in which a plurality of working materials are arranged on the same circumference of the rotating wheel, in principle, the refrigeration efficiency can be further improved.

Moreover, it has the advantage that the entire device can be made smaller.

However, the conventional rotary magnetic refrigeration apparatus has the following problems. That is, in the two-rotation type, the working material is supported by one wheel that usually rotates nine times, and a magnetic field is applied to a part of the circular orbit through which the working material passes, thereby causing adiabatic magnetization.

As mentioned above, when the working material is in an adiabatic magnetized state, 2
It is necessary to exhaust the heat generated by the work material to the outside. For this reason, in conventional rotary magnetic refrigeration equipment, a thermal conductor is placed sufficiently close to both end faces located in the axial direction of the rotating wheel on the surface of the work material located in the magnetic field, and the thermal conductor is The system uses a method to exhaust heat. With such a heat exhaust path configuration, the heat generated in the working substance is led to the thermal conductor through the gap that exists between the working substance and the thermal conductor. Within the gap mentioned above.

Usually, a gas to be condensed is present. therefore.

The heat generated by the working material is transferred to the thermal conductor via the condensed gas layer, but the thermal conductivity of the condensed gas layer is not very high. Therefore, there is a problem in that the heat exhaust efficiency is poor and the refrigeration efficiency is also low due to this.

Therefore, in order to solve the above problems.

It is conceivable to widen the facing area between the working material and the heat conductor, but since it is a one-turn type, it cannot be made that wide.

(Problems to be Solved by the Invention) As described above, the conventional rotary magnetic refrigeration apparatus has a problem in that the efficiency of heat exhaustion during adiabatic magnetization is poor, resulting in low refrigeration efficiency.

Therefore, an object of the present invention is to provide a rotary magnetic refrigeration device that can improve heat exhaust efficiency during adiabatic magnetization without impairing the characteristics of a single-rotation type, thereby improving refrigeration efficiency.

[Configuration 1 of the Invention (Means for Solving Problems) The present invention adopts a configuration in which a working material is supported by a rotating wheel, and when the working material is located in a magnetic field, the heat generated in the working material is reduced. The target is a rotary magnetic refrigeration system equipped with a means for guiding the liquid out of the insulated container. In such a device 9 the present invention provides.

A rotating wheel is provided substantially axially movably with respect to the rotating shaft, and a heat collecting surface formed on one end side is provided with a means for guiding the heat generated in the working material out of the heat insulating container. and is provided at a position where it can slide into one end surface of the work material supported by the rotary wheel located in the axial direction of the rotary wheel, and the other end side is thermally connected to a heat exhaust system. a fixed heat conductor, and a fixed heat conductor that is arranged to face the heat collection surface of the fixed heat conductor with the rotating wheel as a boundary, and presses the work material against the heat collection surface while slidingly contacting the other surface of the work material. It consists of an elastic pressing mechanism.

<Function> As the rotating wheel rotates, when the working material supported by the rotating wheel enters the magnetic field, the working material enters an adiabatic magnetized state and generates heat. At this time, when one end surface of one working material rotates to a position where it contacts the heat collecting surface of the fixed heat conductor, this working material is pressed against the heat collecting surface of the fixed heat conductor by the elastic pressing mechanism. As mentioned above, the rotary wheel supporting one workpiece is supported so as to be substantially movable in the axial direction with respect to the rotating shaft, so that one end surface of the second workpiece and the heat collecting surface of the fixed heat conductor are connected to each other. Even if they are not completely parallel, they are in perfect contact. In other words, the thermal resistance between the two working materials and the fixed heat conductor becomes a sufficiently small value. Therefore, the heat generated by one working material is quickly exhausted via the fixed heat conductor.

(Example) An embodiment of the present invention will be described below with reference to the drawings.

FIG. 1 shows an example in which a rotary magnetic refrigeration device according to an embodiment of the present invention is incorporated into a helium liquefaction device.

In the figure, 1 indicates a helium tank. This helium tank 1 includes an outer tank 2 and a helium container 3 that is housed within the outer tank 2 and directly stores liquid helium H.

It consists of a shield plate 4 provided between this helium container 3 and an outer tank 2. The space 5 between the outer tank 2 and the shield plate 4 and the space 6 between the shield plate 4 and the helium container 3 are each evacuated and formed into a vacuum insulation layer.

In addition, outer tank 2. The helium container 3 and the shield plate 4 are made of non-magnetic material.

Helium container 3 in the space surrounded by shield plate 4
An auxiliary container 7 having a disc-shaped outer shape is located above the
are arranged with their axes facing up and down. This auxiliary container 7 is made of a non-magnetic material. The inside of the auxiliary container 7 and the inside of the helium container 3 are connected by a cylindrical body 8 at an eccentric position. A hole 9 is provided in the center of the clay wall of the auxiliary container 7, and the lower end of the cylindrical body 10 is airtightly connected to the peripheral edge of the hole 9. The upper end of this cylindrical body 10 hermetically passes through the shield plate 4 and is hermetically connected to the peripheral edge of a hole 11 provided in the earthen wall of the outer tank 2 .

On the other hand, inside the auxiliary container 7, a highly elastic disc-shaped rotary wheel 12 whose nine peripheral edges are movable in the axial direction is rotatably housed with its axis oriented in the vertical direction. The rotating wheel 12 is made of a non-magnetic material with low thermal conductivity and is fixed to the outer periphery of the shaft 13. The lower end of the shaft 13 is supported by a bearing 14 fixed to the inner surface of the lower wall of the auxiliary container 7, and the upper end is supported by a bearing 15 fixed to the inner surface of the upper wall of the auxiliary container 7. A cylindrical through hole 16 extending vertically is provided at the peripheral edge of the rotating wheel 12.
A plurality of holders 17 made of a non-magnetic material and having a plurality of holders 17 are fixed at equal intervals. A working substance 18 is installed in the through hole 17 of each holder 17, respectively.

Each working substance 18 is, for example, gadolinium, gallium, etc.
It is formed of a single crystal of garnet, and its axial length is approximately equal to the axial length of the holder 17 . The upper end of the shaft 13 that supports the one-rotation wheel 12 is connected to one end of a connecting shaft 19 made of a heat insulating material.
The other end of this connecting shaft 19 extends upward inside the cylinder 10, and then connects to a motor 22 which is fixed to the outer surface of the upper wall of the outer tank 2 via a heat insulating material via bevel gears 20 and 21. Connected to the rotating shaft.

In the auxiliary container 7, in a space on the opposite side of the axis 13 to the side to which the cylinder 8 is connected.

A fixed thermal conductor 23 made of, for example, steel is arranged. A nine trapezoidal protruding heat collecting surface 24 is formed on one end side of the fixed heat conductor 23.

This heat collecting surface 24 is arranged at a position where it can be brought into sliding contact with the lower surface of the circular orbit along which the working material 18 moves, that is, the lower end surface of the moving working material 18. The other end side of the fixed heat conductor 23 airtightly penetrates the earthen wall of the auxiliary container 7 and connects to the auxiliary refrigerator 25.
connected to the heat absorption part of the A guide tube 26 made of a non-magnetic material and extending in the vertical direction is fixed to a portion of the inner surface of the upper wall of the auxiliary container 7 that faces the heat collecting surface 24 . This guide tube 2
A flange 27 extending inward is formed at the lower end edge of 6. The guide cylinder 26 is formed into a cylinder shape with a bottom.
A presser 28 made of a non-magnetic material and having a flange on the opening edge that can engage with the flange 27 is housed so as to be movable in the vertical direction with its bottom wall facing downward. A coil spring 29 is installed between the auxiliary container 7 and the inner surface of the upper wall thereof.

On the outside of the auxiliary container 7, a superconducting coil 30 serving as a magnetic field generator is arranged so as to surround a portion connecting the heat collecting surface 24 and the presser 28, with its axis line perpendicular to the axis line of the rotating wheel 12. ing. This superconducting coil 30 is connected to liquid helium H in the helium container 3 via a heat conduction path (not shown).
It is designed to be cooled by In addition, in FIG. 1, 31 indicates a bearing, and 32 indicates a seal ring.

Next, the operation of the helium liquefaction apparatus configured as described above will be explained.

First, it is assumed that the superconducting coil 30 has been cooled to a predetermined temperature and that a persistent current is flowing through it. Therefore, a magnetic field is applied to the portion connecting the heat collecting surface 24 and the presser 28. It is also assumed that the auxiliary refrigerator 25 is operating.

When the auxiliary refrigerator 25 operates, the thermal conductor 23 is cooled to a sufficiently low temperature, and thereby the heat collecting surface 24 is also cooled to a sufficiently low temperature.

When the motor 22 starts operating in this state, the connecting shaft 19 rotates, and the rotary wheel 12 rotates accordingly. As the rotating wheel 12 rotates, each working material 1
8 moves on one circular orbit and is alternately located inside and outside the magnetic field generated by the superconducting coil 30. When the working material 18 enters the magnetic field, the working material 18 enters an adiabatic magnetized state and generates heat. Further, when one working substance 18 goes out of the magnetic field, this working substance 18 enters an adiabatic demagnetized state and absorbs heat.

In this adiabatic demagnetization state, the helium gas floating on the liquid surface in the helium container 3 and penetrating into the auxiliary container 7 condenses on the surface of the work material 18 . The droplets generated by this condensation pass through the cylinder 8 and fall into the helium container 3. therefore.

This is where the liquefaction of helium is realized.

On the other hand, the work material 18, which is in an adiabatic magnetized state at this time, generates heat. This heat is exhausted to the outside as follows. That is, when one working material 18 is located within the magnetic field, the presser 28 and the heat collecting surface 24 come into sliding contact with the upper and lower end surfaces of this working material 18 .

The pusher 28 is pressed downward by the restoring force of the coil spring 29, and the work material 18 is fixed to the periphery of the highly elastic rotary wheel 12. Therefore, the second work material 18 is pressed against the heat collecting surface 24 by the force of the presser 28 . therefore.

The thermal resistance between the working material 18 and the fixed thermal conductor 23 becomes sufficiently small, and as a result, the heat generated in one working material 18 is quickly exhausted to the auxiliary refrigerator 1 m25 via the fixed thermal conductor 23. Therefore, the temperature inside the auxiliary container 7 will not rise due to the heat generated by one working substance 18, and the temperature reduction of the working substance 18 will not be inhibited during adiabatic demagnetization.
A good refrigeration cycle is achieved here.

In this case, in particular by adjusting the restoring force of the coil spring 29 and the elasticity of the rotating wheel 12.

The thermal resistance between the working material 18 and the fixed thermal conductor 23 can be made sufficiently small without adversely affecting the rotational characteristics of the rotating wheel 12. Therefore, the thermal resistance of the entire heat exhaust path can be made sufficiently small without impairing the characteristics of the one-rotation type, so that the heat exhaust efficiency can be improved, and as a result, the refrigeration efficiency can be improved.

FIG. 2 shows an example in which a rotary magnetic refrigeration device according to another embodiment of the present invention is incorporated into a helium liquefaction device.
The same parts as those in the figure are indicated by the same reference numerals. Therefore, a detailed explanation of the overlapping portion will be omitted.

In this embodiment, a rigid structure made of non-magnetic material is used as the one-rotation wheel 12a.
a is connected to the shaft 13 via a spline mechanism 41 so as to be movable in the axial direction, and a stopper 42 roughly fixed to the shaft 13 and a coil spring 43 mounted between the rotary wheel 12a and the shaft 13 The rotating wheel 12a is always held at a stable position on the opposite side from the heat collecting surface 24. Further, a plurality of through holes 44 extending vertically on the same circumference are provided at equal intervals on the peripheral edge of the nine-rotation wheel 12a, and the work material 18 is installed in these through holes 44. Further, a branch piece 45 is provided at the upper part of the heat conductor 23 located inside the auxiliary container 7.

A through hole 46 extending in the vertical direction is provided in a portion of the branch piece 45 facing the heat collecting surface 24, and a presser 47 is mounted in the through hole 46 so as to be movable in the vertical direction. He is trying to fix it to the branch piece 45 via a spring 48. Even with this configuration, it is possible to exhibit a good heat exhaust function as in the above embodiment.

Note that the present invention is not limited to the embodiments described above. That is, in the embodiments described above, a superconducting coil is used as the magnetic field generator.

Normally conducting coils may also be used. Moreover, although the above-mentioned embodiment is an example in which the rotary magnetic refrigeration device according to the present invention is incorporated into a helium liquefaction device, it goes without saying that it can also be used to liquefy other gases.

1. It goes without saying that various modifications can be made without departing from the gist of the present invention.

[Effects of the Invention] As described above, according to the present invention, the rotary wheel that supports the work material is provided so as to be movable substantially in the axial direction with respect to the rotating shaft, and the heat generated by the work material is insulated. A heat collecting surface formed on one end side of the means for guiding out of the container may be in sliding contact with one end surface of the work substance supported by the rotating wheel, which is located in the axial direction of the rotating wheel. a fixed thermal conductor whose other end is thermally connected to the heat exhaust system; Since it is constructed with an elastic pressing mechanism that presses the work material against the heat collecting surface while slidingly contacting the surface, it does not complicate the structure or impair the characteristics of the rotary type, and furthermore, the material can be collected easily. Even if the hot surface and the surface of the work material in sliding contact with it are not completely parallel, heat can be quickly removed from the work material during adiabatic magnetization, and as a result, refrigeration efficiency can be improved. .

[Brief explanation of the drawing]

FIG. 1 is a schematic vertical sectional view showing an example in which a rotating magnetic refrigeration device according to an embodiment of the present invention is incorporated into a helium liquefaction device;
FIG. 2 is a schematic vertical sectional view showing an example in which a rotary magnetic refrigeration device according to another embodiment of the present invention is incorporated into a helium liquefaction device. 1... Helium tank, 3... Helium container, 7...
Auxiliary container, 12.128... Rotating wheel, 18...
- Working material, 19... Connection shaft, 22... Motor, 2
3... Fixed thermal conductor, 24... Heat collecting surface, 25... Auxiliary refrigerator, 27... Guide tube, 28... Presser, 2
9...Coil spring. 30...Superconducting coil, H...liquid helium. Applicant's agent Patent attorney Takehiko Suzue Figure 1

Claims (3)

[Claims] (1) An insulated container, a magnetic field generator that generates a magnetic field in a part of the insulated container, and a magnetic field generating device that generates heat when placed inside the insulated container and is located within the magnetic field generated by the magnetic field generator. a working material that absorbs heat and condenses gas to be condensed on its outer surface when located outside; a rotating wheel that supports this working material; and a rotating wheel that rotates the working material to move the working material into and out of the magnetic field. A rotary magnetic refrigeration device comprising rotation driving means arranged alternately and means for guiding heat generated in the working substance out of the heat insulating container when the working substance is located in the magnetic field,
The rotating wheel is supported substantially axially movably with respect to the rotating shaft, and the means for guiding the heat generated in the working substance to the outside of the heat insulating container includes a heat collecting surface formed on one end side. is disposed within the magnetic field and at a position where it can slide into sliding contact with one end surface of the work material supported by the rotary wheel located in the axial direction of the rotary wheel, and the other end side is thermally connected to the heat exhaust system. a fixed thermal conductor connected to the fixed thermal conductor, and a fixed thermal conductor that is provided in a relationship opposite to the heat collecting surface of the fixed thermal conductor with the rotating wheel as a boundary, and that collects the heat of the working material while slidingly contacting the other end surface of the working material. A rotary magnetic refrigeration device characterized by comprising an elastic pressing mechanism that presses against a surface. (2) The rotation according to claim 1, wherein the rotating wheel is configured with a spring member whose peripheral portion is displaceable in the axial direction, and supports the work material at the peripheral portion. type magnetic refrigeration device. (3) The rotating wheel is connected to the rotating shaft by a spline mechanism, and is held in an eccentric state toward the elastic pressing mechanism by a spring force. Rotary magnetic refrigeration device.