JPH06215899A - Multipolar magnet for accelerator - Google Patents

Abstract

PURPOSE:To provide an inexpensive multipolar magnet easy to manufacture. CONSTITUTION:Of exciting coils 2, 2', 3, 3', current is carried to the coils 2', 3' in the direction of penetrating the paper surface, and to the coils 2, 3 in the reversed direction. In such a constitution, a magnetic field is generated as shown in the drawing. This magnetic field can generate the same magnetic field as a conventional quadrupole magnet having a coil wound on each pole. Since the number of coils used in the conventional multipolar magnet can be reduced to half, the cost can be reduced by the reduction in material cost and the number of process, and the assembling is facilitated.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a linear accelerator for generating a charged particle beam, and a multipole magnet used in a circular accelerator system for injecting and accumulating a charged particle beam from the linear accelerator.

[0002]

2. Description of the Related Art Conventionally, in a multi-pole magnet used for an accelerator, the four-pole magnet described in P.98 of the accelerator (Nuclear Physics Course 6 Editor Hiroo Kumagai Kyoritsu Shuppan Co., Ltd.) is used for each pole. The excitation coil is wound. Further, generally, a magnetic field correction coil is also wound around each pole.

[0003]

Conventionally, in a multipole magnet,
Since the excitation coil and the magnetic field correction coil are wound around each pole, there are problems that the manufacturing is troublesome, the winding is difficult, and the manufacturing is difficult.

An object of the present invention is to provide a multi-pole magnet which is easy to manufacture.

[0005]

The object of the present invention can be solved by winding the exciting coil and the magnetic field correcting coil, which are conventionally wound around each pole, on the poles skipped one by one. This can also be achieved by reducing the number of excitation coils and magnetic field correction coils to half the number of poles.

[0006]

By exciting the exciting coils, which are placed apart from the poles of the multipolar magnet, it is possible to generate a multipolar magnetic field similar to the conventional multipolar magnet having the exciting coil wound around each pole. In addition, by exciting the magnetic field correction coils that are placed one for each pole of the multi-pole magnet, the magnetic field correction can be performed in the same manner as in the case where the magnetic field correction coil is wound around each conventional pole. Also, by making the number of coils half the number of poles, the same effect as this action can be obtained.

[0007]

EXAMPLES Examples of the present invention will be described in detail below.

FIG. 1 is a sectional view of a quadrupole magnet in which an exciting coil is wound around one pole of the present invention. In the figure, 1 is a magnet iron core. 2, 2 ', 3, 3'are excitation coils, 2, 2'is one coil, 3, 3'is one coil, and 2', 3'are 2, 3 Has a current flowing in the opposite direction. In this way, when the exciting coils are installed at the poles skipped one by one, the magnetic field is generated as shown by 4. This magnetic field can generate a magnetic field similar to the magnetic field created by a conventional quadrupole magnet having a coil wound around each pole. Therefore, the wound coil can obtain a magnetic field similar to the conventional one with half the conventional coil. Also, by passing a current in the opposite direction, a quadrupole magnet having opposite characteristics is obtained. FIG. 2 shows a sectional view of a 4-pole magnet when the number of coils is half the number of poles.
In the figure, 21 is a magnet iron core. 22,22 ', 23,2
3'is an excitation coil, 22 and 22 'are one coil, and 23 and 23' are one coil, 22 'and 23'.
The current flows in the direction of penetrating through the sheet of paper and in the opposite direction of 22 and 23. With such a configuration, the magnetic field is generated as in 24. This magnetic field can generate a magnetic field similar to a conventional quadrupole magnet having a coil wound around each pole. Also, by passing a current in the opposite direction, a quadrupole magnet having opposite characteristics is obtained.

FIG. 3 is a sectional view of a 6-pole magnet in which an exciting coil is wound around one pole of the present invention. Reference numeral 31 in the drawing is a magnet iron core. 32, 32 ', 33, 33', 34,
34 'is an exciting coil, 32, 32' is one coil, 33, 33 'is one coil, 34, 34' is one coil, and 32 ', 33', 34 'penetrates into the paper surface. , 32, 33, 34 have current flowing in the opposite direction. In this way, when the exciting coils are installed at the poles skipped one by one, the magnetic field is generated as in 35. This magnetic field can generate a magnetic field similar to a conventional 6-pole magnet having a coil wound around each pole. In addition, by passing a current in the opposite direction, a 6-pole magnet having opposite characteristics is obtained.

FIG. 4 shows a sectional view of a 6-pole magnet when the number of coils is half the number of poles. In the figure, 41 is a magnet iron core. 42, 42 ', 43, 43', 44, 44 'are excitation coils, and 42, 42' are one coil, 4
3, 43 'is one coil, 44, 44' is one coil, and 42 ', 43', 44 'have a current penetrating in the plane of the paper, and 42, 43, 44 have a current flowing in the opposite direction. With such a configuration, the magnetic field is generated as shown by 45. This magnetic field is 6
A magnetic field similar to that of a polar magnet can be generated. In addition, by passing a current in the opposite direction, a 6-pole magnet having opposite characteristics is obtained.

Although the 4-pole and 6-pole magnets have been described, the same applies to multi-pole magnets having more poles. Also, in the case of the magnetic field correction coil, the winding method is the same as that of the excitation coil, and therefore the description thereof is omitted.

The exciting coil and the magnetic field correcting coil of the present invention can be used in combination, or can be used in combination with the conventional method of winding the coil around each pole. An embodiment in which the magnetic field correction coil of the present invention is wound around a conventional quadrupole magnet will be described below with reference to FIG. In the figure, 51 is a magnet iron core 52, and a conventional magnetizing coil is wound around each pole. 5
Reference numeral 3 is a correction coil installed at one skipping pole of the present invention. The magnetic field can be corrected by exciting the correction coil 53.

[0013]

According to the present invention, the number of coils used in the conventional multi-pole magnet can be halved, so that the material cost and the cost can be reduced by reducing the man-hours, and the coils can be wound on all the poles. Since it is unnecessary, easy assembly is possible.

[Brief description of drawings]

[Fig. 1] 4 with an exciting coil wrapped around one pole
The top view of a polar magnet.

FIG. 2 is a plan view of a quadrupole magnet in which the number of exciting coils is halved as compared with the conventional one.

[Fig. 3] 6 with an exciting coil wound around one pole
The top view of a polar magnet.

FIG. 4 is a plan view of a 6-pole magnet in which the number of exciting coils is halved as compared with the conventional one.

FIG. 5 is a plan view of a quadrupole magnet in which a magnetic field correction coil of the present invention is wound around a conventional quadrupole magnet.

[Explanation of symbols]

1, 21, 31, 41, 51 ... Magnet iron core, 4, 24 ... 4
Polar magnetic field, 22, 23, 32, 33, 34, 42, 43,
44, 52 ... Excitation coil, 35, 45 ... 6-pole magnetic field.

Claims (6)

[Claims] 1. A multi-pole magnet for use in an accelerator, wherein the number of exciting coils is smaller than the number of poles. 2. A multipole magnet for use in an accelerator, wherein the number of exciting coils is half the number of poles. 3. A multi-pole magnet for an accelerator, wherein a multi-pole magnet used in the accelerator is provided with an exciting coil at a pole separated by one. 4. A multipole magnet for use in an accelerator, wherein the number of magnetic field correction coils is smaller than the number of poles. 5. A multipole magnet for use in an accelerator, wherein the number of magnetic field correction coils is half the number of poles. 6. A multi-pole magnet for an accelerator, wherein a multi-pole magnet used in the accelerator is provided with a magnetic field correction coil at a skipping pole.