JPH01209706A - Structure of magnetic pole - Google Patents

Abstract

PURPOSE:To form an extremely uniform magnetic field and to omit adjustment, by providing optical parallel flat plates as spacers between a pair of magnetic poles, specifying the gap between the magnetic poles, and thereby specifying the parallelism of the gap between the magnetic poles highly accurately. CONSTITUTION:Planar magnetic poles 2 and 3 are made to face optical parallel glass plates 4 and 5 as spacers. A unitary body is formed with a bonding agent 6. A space 8 surrounded with the magnetic polses 2 and 3 and the optical parallel plates 4 and 5 becomes a space for a magnetic field. When the optical parallel plates 4 and 5 are held as the spacers, the gap between the magnetic poles 2 and 3 is strictly specified. Therefore, the uniform, highly accurate magnetic field is formed in the space 8.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to magnetic pole structures, and particularly to magnetic pole structures useful for use in uniform magnetic field generators for NMR and ESR devices.

[Prior art]

In an NMR device or an ESR device, it is necessary to generate a -like and strong magnetic field.

Such a magnetic field can be formed in a gap by making a north magnetic pole and a south magnetic pole face each other with a gap therebetween.

However, in order to obtain precise uniformity of the magnetic field, adjustment means have conventionally been required;
The spacing between the magnetic poles can be adjusted with screws as disclosed in the above publication, or the magnetic path can be adjusted on the side of the air gap as disclosed in Japanese Utility Model Application Publications No. 166111/1982 and No. 88210 of 1982. Additional magnetic pole structures have been proposed.

[Problem to be solved by the invention]

According to the conventional magnetic pole structure described above, an attempt is made to obtain a -like and strong magnetic field by adjusting the magnetic pole spacing and the magnetic flux path, but there is a limit to the accuracy that can be obtained with such adjustment, and it is difficult to obtain a magnetic field of 10 or more. -There is a problem in that it is not possible to obtain the characteristics. Further, there is a problem that the adjustment work itself is not easy.

Therefore, the object of the present invention is to have a simple structure,
It is an object of the present invention to provide a magnetic pole structure that does not require adjustment and can also obtain a magnetic field pattern of 10 or more.

[Means to solve the problem]

In order to achieve the above object, the magnetic pole structure of the present invention has a magnetic pole structure in which a pair of magnetic poles are opposed to each other with an air gap in order to form a magnetic field space. A structural feature is that the magnetic pole gap is defined by

In the above configuration, the optical parallel plate may be made of a transparent material having a -like refractive index, such as glass or hard plastic.

[Effect]

Optical parallel plates made of transparent materials with a negative refractive index achieve parallel accuracy up to approximately 1716 wavelengths of light by repeatedly performing accuracy evaluation and optical polishing using the interference of reflected light from the front and back surfaces. I can do it.

Therefore, when such an optical parallel plate is used as a spacer, the gap between the magnetic poles can be defined with extremely high precision, so a desired magnetic field, especially a transverse magnetic field, can be easily obtained, the structure is simple, and adjustment is possible. is also no longer necessary.

〔Example〕

Hereinafter, the present invention will be explained in more detail based on embodiments shown in the drawings. Here, FIG. 1 is a perspective view of a magnetic pole structure according to an embodiment of the present invention, FIG. 2 is a front view of a uniform magnetic field generator using the magnetic pole structure shown in FIG. 1, and FIG. FIG. 4 is a front view of another embodiment of the present invention, FIG. 5 is a front view including a partially cutaway view of still another embodiment of the present invention, FIG. 6 is a perspective view of a magnetic pole structure in which a shim coil is added to the embodiment shown in FIG. 1, FIG. 7 is a front view of a uniform magnetic field generator using the magnetic pole structure shown in FIG. 6, and FIG.
The figure is a conceptual diagram showing the magnetic flux of the uniform magnetic field generator shown in Fig. 7,
9 is a perspective view including a partially cutaway view of the magnetic pole structure in which a leakage magnetic flux prevention wall is added to the embodiment shown in FIG. 1, and FIG.
A front view of a uniform magnetic field generator using the magnetic pole structure shown in the figure, Fig. 11 is a conceptual diagram showing the magnetic flux in the uniform magnetic field generator shown in Fig. 1O, and Fig. 12 is a uniform magnetic field generator shown in Fig. 2. FIG. 13 is a perspective view of a main part of a chemical plant including a process sensor using a uniform magnetic field generator shown in FIG. 2. It should be noted that the present invention is not limited to the embodiments shown in the figures.

In the magnetic pole structure l shown in FIG.
are opposed to each other using an optical parallel flat glass 4.5 as a spacer, and are integrated with an adhesive 6. (Note that the adhesive 6 is exaggerated.) As the material for the magnetic poles 2 and 3, commercially pure iron of less than CO, OS% can be used.

A cross roller bearing 7 is attached to a portion of the upper and lower corners of the magnetic pole 2.3, so that it can be easily incorporated into the uniform magnetic field generator 10 shown in FIG.

That is, as shown in FIG. 2, the -transverse magnetic field generator 10 has the columnar return yokes 12 and 13 interposed inside the cylindrical return yoke 11, and the permanent magnets 14 and 15 are fixed between the plates. The magnetic pole structure 1 is inserted into the gap between the magnets 14 and 150.

A space 8 surrounded by the magnetic pole 2.3 and the optical parallel plate 4.5 becomes a magnetic field space.

Figure 3 schematically shows the magnetic field formed between the magnetic poles 2.3, and as mentioned above, by sandwiching the optical parallel plate 4.5 as a spacer, the air gap between the magnetic poles 2.3 is tightly controlled. Therefore, a highly accurate uniform magnetic field is formed in the space 8.

FIG. 4 shows a magnetic pole structure 21 of another embodiment, in which flanges 22, . 23. are provided, and after making both magnetic poles 22 and 23 face each other using an optical parallelism ratio @24.25 as a spacer, the flange portion 22.
．． 23. are connected with bolts 26 and nuts 27 to form an integrated unit.

FIG. 5 shows a magnetic pole structure 31 of yet another embodiment,
Mounting holes are provided that pass through the plate-shaped magnetic poles 32, 33 and the optical parallel plates 34, 35, and bolts 36 are passed through the mounting holes, and they are integrally connected with nuts 37.

Now, as can be understood from FIG. 3, in the magnetic pole structure 1, a highly accurate uniform magnetic field is obtained at the center of the space 8, but at the ends, the magnetic flux spreads outward, so the magnetic field becomes slightly uniform. There are some points where the pattern and parallelism are inferior.

Therefore, the magnetic pole structure 41 shown in FIG.
A shim coil 42 is provided so as to surround the outer periphery of the optical parallel plate 4.5 to improve the uniformity and parallelism of the magnetic field.

The uniform magnetic field generator 50 using this magnetic pole structure 41 has a seventh
As shown in the figure, it has the same structure as the uniform magnetic field generator 10 shown in FIG. 2, except that a shim coil 42 is added.

FIG. 8 schematically shows the magnetic field formed between the magnetic poles 2.3 of the transverse magnetic field generator 50, in which a current is passed through the shim coil 42 in the direction of increasing the magnetic flux between the magnetic poles 2.3, magnetic pole 2
, 3 suppresses the magnetic flux from spreading outward.

In addition, in the magnetic pole structure 61 shown in FIG. 9, in order to improve the uniformity and parallelism of the magnetic field as described above, the outer periphery of the magnetic pole structure 1 is surrounded by a container 63, and a coolant is placed inside the container 63. (not shown) and a superconducting material plate 62.

As the material for the superconducting material plate 42, an alloy superconducting material or a composite oxide superconducting material can be used.

The uniform magnetic field generator 70 using this magnetic pole structure 61 is
It has the same structure as the uniform magnetic field generator 10 shown in FIG. 2, except that the B conductive material plate 62 shown in the figure is added.

FIG. 11 schematically shows the magnetic field in the transverse magnetic field generator 70, in which the Meissner effect of the superconducting material plate 62 prevents the magnetic flux from spreading outward at the ends of the magnetic poles 2 and 3. As a result, the magnetic field properties and parallelism are improved.

FIG. 12 shows an application of the transverse magnetic field generator IO to an NMR analyzer 80. The sample S is inserted into the space 8. 81 is an excitation coil, and 82 is a detection coil. - Instead of the transverse magnetic field generator 10, - the transverse magnetic field generator 30 or the uniform magnetic field generator 70 can be used.

Next, FIG. 13 shows a chemical plant 90 using the transverse magnetic field generator IO as a process sensor. 9
1 is a reactor, and 92 is a pump. - Instead of the transverse magnetic field generator IO, - the transverse magnetic field generator 50 or the uniform magnetic field generator 70 can be used.

〔Effect of the invention〕

According to the present invention, in a magnetic pole structure in which a pair of magnetic poles are opposed to each other with an air gap in order to form a magnetic field space, an optical parallel plate is interposed between the pair of magnetic poles as a spacer to define the magnetic pole gap. A unique magnetic pole structure is provided, which allows the parallelism of the magnetic pole gap to be defined with high precision (approximately 500 magnets/cm), making it possible to form an extremely similar magnetic field of more than 1O in the gap, and also to make adjustment possible. No longer needed. Therefore, it becomes possible to easily obtain a high-resolution NMR device or ESR device.

[Brief explanation of the drawing]

FIG. 1 is a perspective view of a magnetic pole structure according to an embodiment of the present invention, FIG. 2 is a front view of a uniform magnetic field generator using the magnetic pole structure shown in FIG. A schematic diagram showing magnetic flux in a magnetic field generator, FIG. 4 is a front view of another embodiment of the present invention,
FIG. 5 is a front view including a partially cutaway view of still another embodiment of the present invention, FIG. 6 is a perspective view of a magnetic pole structure in which a shim coil is added to the embodiment shown in FIG. 8 is a conceptual diagram showing the magnetic flux of the uniform magnetic field generator shown in FIG. 7, and FIG. 9 is a front view of a uniform magnetic field generator using the magnetic pole structure shown in the figure.
! FIG. 10 is a perspective view including a partially cutaway view of the magnetic pole structure in which a leakage flux prevention wall is added to the embodiment shown in FIG. 9; FIG. 10 is a front view of a uniform magnetic field generator using the magnetic pole structure shown in FIG. 9; The figure is a conceptual diagram showing the magnetic flux in the uniform magnetic field generator shown in Fig. 10, Fig. 12 is a perspective view of the main part of the NMR analyzer using the uniform magnetic field generator shown in Fig. 2, and Fig. 13 is a schematic diagram showing the magnetic flux in the uniform magnetic field generator shown in Fig. 2. FIG. 2 is a perspective view of a main part of a chemical plant including a process sensor using the uniform magnetic field generator shown in the figure. [Explanation of symbols] 1.21, 31.41.61...Magnetic pole structure 2.3...
・Magnetic pole 4.5...Optical parallel plate 6...Adhesive 7...Cross roller ring 8...Magnetic field space 10.50.70...-Transverse magnetic field generator 14.15...
- Permanent magnet 42...Shim coil 62...Superconducting material plate 63...Container 80...NMR analyzer 90...Chemical plant.

Claims (1)

[Claims] 1. A magnetic pole structure comprising a pair of magnetic poles facing each other with an air gap in order to form a magnetic field space, characterized in that an optical parallel plate is interposed between the pair of magnetic poles as a spacer to define the magnetic pole gap.