JPS5843367A - 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 The present invention relates to a magnetic refrigerator, and more specifically, to a magnetic refrigerator, more specifically, a single crystal of a rare-earth coiled-spin rearranged phosphorus compound, which is a single crystal with 41 crystal directions aligned, is produced in a static field Φ. When rotated,
When a magnetic field is applied, depending on the direction, ms'-(D increases-
This relates to a refrigerator that performs cooling (by means of lead dripping and fins).

Conventionally, magnetic refrigeration using so-called magnetic quenching mK was performed by adding or removing a strong field of several Tesla to a resident salt.
It is based on the principle of heat radiation or heat absorption. This method requires a strong magnetic field as described above, and mono-resident salts are effective at temperatures below helium temperature], and ferromagnetic materials have drawbacks such as problems with sealing and insulation when entering and exiting the magnetic field. .

It is an object of the present invention to provide a magnetic refrigerator which does not have the above-mentioned drawbacks.

The above object of the present invention is to seal a magnetic material i in a manner such that the crystal constituting the magnetic material is a single crystal whose direction of easy magnetization changes depending on the temperature or a crystal in which at least one crystal direction is aligned. In the static magnetic field of chamber 2, the magnetic material 1 is rotated with K at -.
If the direction is the direction in which the crystal temperature increases, the IK is brought into contact with the medium on the high temperature side, and if the direction is the direction in which the crystal temperature decreases, it is brought into contact with the medium on the low temperature side, and the low temperature side is brought into contact with the medium. It is possible to accomplish this by using an all-in-one refrigerating machine with a 41 image. A magnetic material whose orientation direction is the easy magnetization direction of the single crystal (such as a single crystal or a polycrystal with at least one crystal orientation) has a magnetic material in which the easy magnetization direction of the entire magnetic material is one of the orientation directions. Match. When this magnetic material is placed in a static magnetic field, when the direction of easy magnetization of the magnetic material is parallel to the direction of the magnetic field, the magnetization of the l1m material by the magnetic field is maximum, and when this is perpendicular, the magnetization is minimum. .

When such a magnetic material is rotated in a static magnetic field in a temperature range that does not include the temperature at which the direction of easy magnetization changes, the entropy change is extremely small. When the direction of easy magnetization is changing, the entropy changes greatly, and heat generation or heat absorption occurs during rotation. 1:・:、
The present invention is based on the above principle. :□・・
・□・ ・The four materials used in the present invention are rare earths... ~ 臘 alloys, and the direction of easy magnetization changes to the true direction from two planes and clii as shown in Figure 1, depending on the temperature wtK. □. A magnetic material made of polycrystals oriented in one crystal direction is obtained even at a temperature higher than the transition temperature at which the magnetic material turns in the incoming direction. Rare earth core/4 rut type alloy is RCo 5m, R, C60, fl
i is 6 choices. The relationship between the easy magnetization direction and temperature for these alloys is shown in FIGS. 2 and 3. In the RC type alloy, for example, the temperature at which the direction of easy magnetization of DyCo turns from the zero plane to the true direction is about 370''K, and it can be used at a temperature higher than this. Furthermore, 8 of this alloy
%Co can be partially replaced with other elements.

The basic operation of the magnetic refrigerator will be explained with reference to FIG. The magnetic material 1 is made up of crystals whose direction of easy magnetization changes depending on the temperature, and these crystals are oriented in at least one crystal direction and rotated within the hermetic seal 11ii12. A sealed chamber 261-
What makes a static magnetic field work? Magnetic! 1#9. Carr, -
1, & □, oh, ka. .

In this case, a low-temperature medium is introduced into the sealed chamber 2, brought into contact with the magnetic material 1, cooled, and circulated through the low-temperature circuit 3. On the other hand, while the direction of the magnetic material 1 is in the direction in which the crystal temperature increases, contact with the low-temperature medium is stopped, and the high-temperature medium is allowed to flow in and circulate to the high-temperature circuit 4.

The magnetic refrigerator of the present invention is different from conventional ones based on adiabatic demagnetization, and exhibits a sufficient refrigeration function by rotating in a static magnetic field similar to that obtained with ordinary permanent magnets or electromagnets. be able to. By using a rare earth cobalt type alloy with a transition temperature lower than room temperature,
It can be frozen at room temperature. In addition, compared to conventional gas refrigerators, the volume of working material is approximately 1/300th
Since it is small in size and does not require a high-pressure compressor, it can be downsized and reduce noise and vibration.
1 It is thought that it can also be used for

Next, the main parts of the embodiment 1) of the cicada refrigerator of the present invention will be explained with reference to FIG. Ml! # Department DF,
The transition temperature at which the easy magnetization direction of , -machi, 1 ("O,?'・.,,) changes from the C solid direction to the true direction is 55 C, and does not change above this temperature. This crystal is heated to a temperature of 100 C.
Magnetic at ℃! The compacted powder compacted in the chamber was heated to 1200°C
h Sintered. This sintered body was processed to form a fan-shaped body a with a large number of through-holes, each fan-shaped body weighed 13II, and four fan-shaped bodies were adiabatically bonded to form a magnetic material l. The magnetic material 1 can be rotated in contact with the inside 11 of the sealed chamber 2.
A quiet field source is arranged on both sides of the sealed chamber 2, a medium outlet is provided at right angles to the direction of the Ka field of the sealed chamber 2, and a medium water (30%) is poured from the inner cavity 5 of the magnetic material 1. Alcohol (7,0-) was flowed in at a flow rate of 100-c.

, Magnetism, Material, Family 1 is rotated clockwise at lrpm, f
The strength of the magnetic field passing through the fl edge material 1 was set to 4 kO·.

At position 5 shown in FIG. 5, the directions of easy magnetization of the sectors a and b change from parallel to perpendicular to the direction of the field a6')')
Therefore, the magnetic material 1 demagnetizes and absorbs heat.

At this time, the low temperature side circuit 3 is opened by operating the valve 6 of the Koryu skewer. Next, when Km-sensitive material 1 rotates and the previous direction changes from a right angle to a half line, the low temperature side circuit is closed and the high temperature is reached! Open to circuit 4. The low-temperature side circuit 3 includes a conduit and a pump (not shown). The medium on the low temperature side is circulated and returned to the inner cavity 5 of the magnetic material 1.The temperature becomes 1, and the temperature drops from 25.7℃ to 0.7℃9.After 10 minutes of repeating this, the medium temperature The temperature could be lowered to 7℃.

[Brief explanation of the drawing]

Figure 1 is a model diagram of the easy magnetization direction of the single crystal used in the magnetic refrigerator of the present invention, and Figure 2 is a diagram showing the relationship between the easy magnetization direction and temperature of the RCOsl1 alloy single crystal used in the magnetic refrigerator of the present invention. Figure 3 is a graph showing the relationship between the easy magnetization direction and temperature of the "z"<r type combined single crystal used in the magnetic refrigeration quasi of the present invention, and Figure 4 is a graph showing the relationship between the temperature and the direction of easy magnetization. Explanation of the Principle of the Magnetic Refrigerator of the Invention-2 □ FIG. 5 is an explanatory view of the main part of the magnetic cooling embodiment of the present invention.・ □゛1...Magnetic material, 2...Sealed chamber 3...Ass low temperature side medium circuit, 4...High temperature side medium circuit, 5...Inner cavity of magnetic material, 6...Valve. Patent applicant Fujitsu Limited Tokugi Patent attorney Akira Aoki Patent attorney Kazuyuki Nishidate Patent attorney 1) Yukio Patent attorney Akira Yamaguchi '8 ( , '□:, Figure 2, 3@

Claims (1)

[Claims] 1. The crystal that makes up the magnetic material is a single crystal whose direction of easy magnetization changes depending on the temperature, or at least one crystal direction is aligned and the magnetic material (1゛) is sealed. Chamber (2)C) Place the magnetic material (1
) is the direction in which the crystal temperature increases, and the high temperature side is integrated with *! ! A magnetic refrigerator characterized in that it repeatedly brings the temperature of the iris into contact with a low temperature medium to cool the low temperature medium in the direction in which the temperature of the iris decreases.