JPH0315809B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application The present invention relates to a magnetic field device for diametrical excitation having a cylindrical form.

BACKGROUND TECHNOLOGY Conventionally, for example, a magnetic field device installed on the outer periphery of a vacuum chamber containing a rotary circular furnace of a silicon single crystal pulling device for silicon wafers has been used to excite a defined spatial region with direct current. As shown in FIG. 5 of the accompanying drawings, it is formed from a pair of excitation coils 31, a pair of iron cores 32 arranged around the excitation coils, and a yoke 33 that interconnects these iron cores 32. and this results in
The magnetic flux induced by the excitation coil 31 is transferred to its yoke 33.
As shown in _{FIG .} It is typified by a so-called air-core coil type electromagnet device 40 that excites its own internal space R.

Problems to be Solved by the Invention However, these typical conventional methods and devices for DC exciting a space each have drawbacks as described below. That is,
The former counter electrode electromagnet device 30 has the disadvantage that the excitation coil 31 and yoke portion 32 arranged around it are larger than the excitation space R, and the installation space area and weight of the device are also large. In the latter air-core coil type electromagnet device 40, the excitation direction is limited to the winding axis direction of the coil 41, and a yoke that induces and concentrates magnetic flux cannot be used on the opposite pole (if this is installed). In this case, the excitation space R would be sealed, which would limit its utility value and increase power consumption.

The present invention has a new and improved cylindrical form that eliminates the above-mentioned drawbacks of the conventional method or apparatus and also has the features and advantages of the conventional method, and the inner diameter of the cylindrical space is made into a cylindrical shape. The object of the present invention is to obtain a magnetic field device having a function of excitation in the diameter direction of .

Means for Solving the Problems In order to achieve this object, the magnetic field device according to the present invention, as shown in FIG. A semi-cylindrical outer yoke 1, 2, a pair of magnetic pole pieces 5, 6 each assembled into the inner diameter space of each outer yoke 1, 2, and each outer yoke 1, Magnetic pole pieces 5, which are housed in the inner diameter spaces of 2 and assembled on the inner diameter surfaces thereof, respectively.
A diametrically azimuthal excitation device having a cylindrical shape formed by joining a pair of electromagnet halves, each consisting of a pair of excitation coils 7 and 8 formed to fit a magnet 6 inside, to each other at their diametrical surfaces. It is characterized by a magnetic field device for use.

Effect Since the device of the present invention has the above-described configuration, the outer cylindrical yokes 1 and 2 of each electromagnet half are fixed to each other with their diametrical surfaces facing each other, and are integrated. A cylindrical space R extending in the axial direction is formed in the center of the outer cylindrical yokes 1 and 2, and the excitation coils 7 and 8 installed inside this space R are Therefore, when the excitation coils 7 and 8 are energized, the magnetic pole pieces 5 and 6 and the outer cylinder yokes 1 and 2 work together to control the outer cylinder yokes 1 and 2. Magnetic flux is generated in a direction perpendicular to the central axis.

Embodiments Hereinafter, the present invention will be explained in detail based on FIGS. 1 and 2 of the accompanying drawings showing an embodiment thereof, and FIG. 4 showing an example of its application.

First, as shown in FIG.
A pair of outer cylindrical yokes 1 and 2 having a hollow semi-cylindrical shape
And, on the upper and lower ends of each outer cylinder yoke 1 and 2, respectively,
Upper and lower yokes 3 and 4 having a semicircular shape that are fixed to each other, and outer cylinder yokes 1 and 4, respectively, are fixed to each other.
It is designed to be assembled on the inner surface of 2.
A pair of magnetic pole pieces 5 and 6 each having an arcuate cross-sectional shape, a certain thickness, and a certain height are housed inside the inner diameter spaces of the outer cylinder yokes 1 and 2, respectively. It is composed of a pair of excitation coils 7 and 8 that have a special shape so that they can be fitted into magnetic pole pieces 5 and 6 assembled on the inner diameter surface of the magnet.

Here, the shape of each excitation coil 7, 8 will be explained in more detail as follows. That is, as shown in FIG. 1, each excitation coil 7, 8 is a substantially outer cylinder whose end portion is arranged axially within the diametric plane of each outer cylinder yoke 1, 2. Yoke 1,
A pair of linear portions 7 ₁ and 8 ₁ having a length corresponding to the height of 2 and each end thereof is connected to each other, and approximately corresponds to the inner diameter of the outer cylinder yokes 1 and 2. It consists of a pair of semicircular annular parts 7 _{2 and} 8 ₂ having _an outer diameter of
The magnetic pole pieces 5 and 6 are fitted into the spaces surrounded by the semicircular annular parts 7 ₂ and 8 ₂ , respectively. Each of the excitation coils 7 and 8 is energized via a node wire 9 connected thereto, and each node wire 9 is connected to an opening formed at the bottom of each outer cylinder yoke 1 and 2. 1 ₁ and 2 ₁ to the outside.

In this way, each electromagnet half body 10 is made up of an outer cylindrical yoke 1, 2, each of which has a magnetic pole piece 5, 6 assembled on its inner diameter surface and an excitation coil 7, 8 accommodated in its inner diameter space. _{1,10 2} is
As shown in FIG. 2, when the outer cylinder yokes 1 and 2 are joined to each other in their diametrical planes and are firmly connected to each other via appropriate fasteners 11 on the outside, a cylindrical yoke is formed inside. It now has a cylindrical shape with a space R, and the excitation coils 7 and 8 installed inside each are closely attached as if they were one coil, and each excitation coil 7 and 8 is energized ( When the direction of the current is indicated by arrow C), the axes of the coils 7 and 8 generate magnetic flux in a direction that coincides with the diameter direction of the cylindrical excitation space R. .

The device of the present invention having such a configuration is used, for example, as a magnetic field device used in the process of manufacturing single crystals for silicon wafers. The present invention provides a small and lightweight device for direct current excitation of the internal core (MCZ method*).Furthermore, it is possible to minimize the magnetic flux leaking around the device of the present invention, and to It is possible to reduce the impact on adjacent equipment (Note: *Magnetic
Field Applied Czochralski method).

In addition, the device of the present invention itself consists of two electromagnet halves 1
Since it can be divided into 0 ₁ and 10 ₂ , as shown in FIG. 4, the device of the present invention can be installed very easily without the need to penetrate the single crystal pulling device 20.

Effects of the Invention Since the present invention has the above-described configuration and operation, it is clear that the present invention can exhibit the following excellent effects.

That is, 1. In the excitation coil in the device of the present invention, two excitation coils can be brought into close contact with each other as if they were just one coil, similar to the air-core coil magnetic field device, and the excitation space can be arranged coaxially. It has a cylindrical excitation space whose orientation is changed by 90 degrees with respect to the axial direction of the excitation coil.3 The shape of the outer cylinder yoke and the excitation coil are arranged without waste in the cylindrical excitation space, and are overall small and compact. 4. The outer cylinder yoke has internal magnetic pole pieces on its inner surface, and can effectively converge the magnetic flux induced by the excitation coil, while also preventing leakage of magnetic flux to the outside. 5. Since both the outer cylinder yoke and the excitation coil are divided into two in the diameter direction, assembly and disassembly are extremely easy.

[Brief explanation of the drawing]

FIG. 1 is an exploded perspective view showing one embodiment of the present invention, FIG. 2 is a perspective view showing the assembled state, FIG. 3 is a vertical sectional view showing the principle of the device of the present invention, and FIG. Fig. 4 is a partially longitudinal front view showing an example in which the apparatus of the present invention shown in Figs. 1 and 2 is arranged in a single crystal pulling apparatus, and Figs. Electromagnetic device 2
It is a longitudinal cross-sectional view showing an example. 1, 2... Outer cylinder yoke, 3, 4... End yoke,
5, 6... Magnetic pole piece, 7, 8... Excitation coil, 7 ₁ ,
8 ₁ ... linear part, 7 ₂ , 8 ₂ ... circular part, 10
...Electromagnet device, 10 ₁ , 10 ₂ ...half electromagnet.

Claims (1)

[Scope of Claims] 1. In a magnetic field device for diametrical excitation having a cylindrical form with a two-pole opposing structure, a pair of semi-cylindrical outer yoke and an inner diameter surface of each outer yoke are provided. a pair of magnetic pole pieces that are adapted to be assembled respectively; a pair of excitation coils that are respectively accommodated in the inner diameter surface space of each outer cylinder yoke and formed so as to fit the magnetic pole pieces therein; Each outer cylinder yoke forms an electromagnet half together with the magnetic pole piece and excitation coil built inside them, and these electromagnet halves are joined to each other diametrically so that they become a single body. A magnetic field device for diametrical excitation having a cylindrical shape. 2. A magnetic field device for diametrical excitation having a cylindrical form according to claim 1, wherein semicircular yokes are fixed to the upper and lower ends of each outer cylinder yoke. 3. Each excitation coil has a straight portion extending in the axial direction at each end within the diameter plane of the outer sleeve yoke and having a length approximately corresponding to the height of the outer sleeve yoke, and a straight portion of this straight portion. Claim 1 or 2 comprises a pair of semicircular annular portions having respective ends connected to each other and having an outer diameter approximately corresponding to the inner diameter of the outer cylinder yoke. A magnetic field device for diametrical excitation having a cylindrical form.