JPH01112712A - magnetic levitation device - 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 Field of Industrial Application The magnetic levitation device according to the present invention is used in transportation equipment, especially small-sized transportation equipment such as indoor equipment, and small-sized weak electrical equipment such as magnetically levitated speakers.

Conventional technology Magnetic levitation devices using superconductivity include devices that use the Meissner effect, in which the superconductor does not allow magnetic flux to penetrate, whereas those that use the ultra-strong magnetic field created by superconducting coils. A composite device is being considered [Survey on superconducting technology from the perspective of resources and energy (Science and Technology Agency Resource Survey New Material No. 144)]. For example, as shown in Figure 3, F
This is a magnetic levitation device that utilizes the repulsive force between a magnetic flux generator made of a permanent magnet or an electromagnet made of a ferromagnetic material such as e, Go, etc., and a plate-shaped superconductor.

In this magnetic levitation device, the magnetic flux generated from the magnetic flux generating body is curved by the completely diamagnetic superconductor, and the density becomes high below the plate-shaped superconductor.

Since the energy of the magnetic field is proportional to the square of the magnetic flux density, a force acts in a direction that reduces the magnetic flux below the plate-shaped superconductor, that is, in an upward direction. Therefore, in order to obtain a strong floating blade, it is necessary to create a structure in which the magnetic flux density at the bottom of the plate-shaped superconductor varies greatly depending on the position of the plate-shaped superconductor.

Problems to be Solved by the Invention However, if the magnetic flux generator has a normal configuration as shown in FIG. As shown in Fig. 4, the magnetic flux is curved within the ferromagnetic core material to prevent the magnetic flux density from increasing at the bottom of the plate-shaped superconductor. As a result, the floating blade is kept within a certain range and does not become large.

Means for Solving the Problems The present invention provides a strong frki
The present invention provides a structure in which the core material is preferably made into thin wires and each wire is wrapped in a superconducting material.

According to the means of the present invention, the magnetic flux inside the ferromagnetic core cannot pass through the wrapped superconductor, so no curvature occurs inside the core, but is generated from the open end face of the core. . As a result, as the floating plate-shaped superconductor approaches the end face of the open core material, the magnetic flux density becomes extremely large. In reality, magnetic flux leaks through a small gap between the plate-shaped superconductor and the magnetic flux generator, so the magnetic flux density does not diverge, but the force acting on the plate-shaped superconductor increases in a divergent manner.

EXAMPLE An example of the present invention is shown in FIG. As a magnetic flux generator, an Fe-based permanent magnet is used as the core material 1, and the outside? Composition formula YB
A plurality of wire rods wrapped in a superconducting material 2 made of an oxide such as a2Cu30p-δ were reinforced by folding them together. The thickness of the superconducting material 2 is constant at 1 cm, the diameter of the core material is 0.1 cm,
The configurations were changed to 1 cm and 5 cm.

As the plate-shaped superconductor 3, a disk-shaped sintered product of the oxide superconductor 2 having the same compositional formula YBa2Cu309-,5 was used, having a thickness of 2 mm and a diameter of 2 cm.

At liquid nitrogen temperature, the repulsive force exerted when the two were brought close to each other up to 2H was measured as a floating blade.

The results are shown in Table 1 in comparison with the conventional method, that is, when using a permanent magnet that is not wrapped in superconducting material.

(The following is a blank space) The method according to the present invention was able to obtain a floating blade that was much stronger than the conventional method. In addition, as the diameter of the core material becomes smaller to I Cm and I Mll, a dramatically stronger floating blade is obtained than when the diameter of the core material is 5 cm. This indicates that the effect of blocking the magnetic flux generated from the edge of the material is large. Therefore, in order to obtain a larger floating blade, it was found that it is better to form a magnetic flux-generating end surface by forming a large number of wires made of a ferromagnetic core material with a smaller diameter and a superconductor surrounding it. .

In this example, a magnetic flux generator was used on one side and a plate-shaped superconductor was used on the other side, but as shown in Figure 2, even if a pair of magnetic flux generators according to the present invention is used, the same strong levitation can be obtained. It is clear that the blade is obtained. Furthermore, the strong floating blade of the present invention is derived from the Meissner effect of the superconducting material surrounding the ferromagnetic core material, so for example, when a magnetic flux generator is constructed using a material that has the Meissner effect at room temperature, Needless to say, a strong floating blade can be obtained at room temperature.

Effects of the Invention If a strong floating blade can be obtained with a relatively simple structure of ferromagnetic material and superconductor as in the present invention, the effect on transportation and transportation technology will be immeasurable.

[Brief explanation of the drawing]

Fig. 1 is a magnetic flux distribution diagram in a magnetic levitation device according to an embodiment of the present invention in which a ferromagnetic core material is wrapped with a superconductor, and Fig. 2 is a diagram of a magnetic flux distribution in a different embodiment of the present invention consisting of a pair of magnetic flux generating devices. Magnetic flux distribution diagrams in a magnetic levitation device. FIGS. 3 and 4 are magnetic flux distribution diagrams when plate-shaped superconductors are separated and close to each other, respectively, in a conventional magnetic levitation device. 1...Ferromagnetic core material, 2...Superconductor,
3...Plate superconductor. Name of agent: Patent attorney Toshio Nakao (1st person)
Figure 2

Claims (3)

[Claims] (1) A magnetic levitation device characterized in that at least one magnetic flux generating device is composed of a ferromagnetic core material and a superconducting material surrounding it. (2) The magnetic levitation device according to claim 1, wherein the open magnetic flux generating end surface of the ferromagnetic core material is smaller than the superconducting material surface of the opposing levitation device. (3) A magnetic levitation device according to claim 1 or 2, in which an oxide superconductor is used as the superconducting material.