JPH04316305A - Iron core structure of electromagnet - Google Patents

Abstract

PURPOSE:To see that the permeability is nearly fixed and high in a steel plate at large by making the steel plate, which constitutes the iron core of an electromagnet, so that the direction of its rolling may be nearly parallel with the direction of the line of magnetic force, and to see that the intensity of a magnetic field in a gap becomes nearly uniform and high by reducing the leaked magnetic field. CONSTITUTION:A steel plate 26, which constitutes the iron core 24 of an electromagnet 22, is made so that the rolling direction 36 may be nearly parallel with the direction of the line 38 of the magnetic force. For example, the iron core of the deflecting electromagnet 22 of synchrotron is constituted by stacking many sheets of silicon plates 26 being made in U shapes, and reinforcing members 34 such as stainless, etc., are welded to the peripheral angles of the iron cores 24 so as to fix the whole. Coils 28 and 30 are wound on the iron core 24 so as to generate a vertical magnetic field in the gap between magnetic poles. The silicon steel plate is put in five-division structure, being divided obliquely at each corner, and those segments are welded with each other to constitute one sheet of silicon steel plate 26. Each division 26a-26e is arranged so that the rolling direction 36 may be parallel with the direction of the magnetic path.

Description

[Detailed description of the invention]

0001

[Industrial Field of Application] The present invention relates to the structure of an iron core constituting an electromagnet, which achieves high magnetic permeability.

0002

2. Description of the Related Art In bending electromagnets used, for example, in synchrotrons, the iron core generally has a laminated structure of silicon steel plates in order to avoid the generation of eddy currents in the iron core when the magnetic field rises. Silicon steel plates are manufactured by rolling, and conventional bending electromagnets are manufactured by punching out rolled silicon steel plates to create a U-shaped silicon steel plate 10 as shown in FIG.
A large number of these were laminated to form an iron core 12, and coils 14 and 16 were wound around this iron core 12.

0003

[Problem to be Solved by the Invention] The relationship between magnetizing force and magnetic flux density in a silicon steel sheet varies depending on the angle θ between the rolling direction of the silicon steel sheet and the direction of the magnetic field lines passing through it, as shown in FIG. , when these two directions are parallel (θ=0
°) has the highest magnetic permeability and deviates from parallel (θ = 90°
), the magnetic permeability decreases. The conventional silicon steel sheet 10 shown in FIG. 2 has a structure in which a rolled silicon steel sheet is simply punched out in a "U" shape, so the rolling direction is all the same as shown by the arrow 18 in FIG. The direction is uniform in this part. On the other hand, since the direction of the magnetic lines of force generated by the excitation of the coils 14 and 16 revolves around the shape of the silicon steel plate 10 as shown by the arrow 20, the angle formed between the rolling direction 18 and the direction of the magnetic lines of force 20 is θ varies in different parts, and the magnetic permeability is not uniform. For this reason, the leakage magnetic field was large, the magnetic field strength at the gap 22 was weak, and it was not possible to obtain a uniform magnetic field. The present invention solves the drawbacks of the conventional technology and can make the magnetic permeability substantially constant and high throughout the steel plate, thereby reducing the leakage magnetic field and making the magnetic field strength at the gap substantially uniform and high. It is intended to generally provide an iron core structure of an electromagnet that can be made high.

0004

[Means for solving the problem] The invention according to claim 1 includes:
The steel plate that constitutes the iron core of the electromagnet is formed so that its rolling direction is approximately parallel to the direction of the magnetic lines of force (the direction of the magnetic path).

[0005] Furthermore, the invention according to claim 2 has a steel plate constituting the iron core of the electromagnet having a divided structure, and each divided portion is arranged so that the rolling direction and the direction of the magnetic lines of force (the direction of the magnetic path) are approximately parallel to each other. It is made by arranging and joining.

[0006]

[Operation] According to the invention as claimed in claim 1, since the steel plate constituting the iron core of the electromagnet is formed so that its rolling direction is approximately parallel to the direction of the lines of magnetic force, the magnetic permeability of each portion of the steel plate is approximately equal to that of the iron core of the electromagnet. The leakage field decreases, making the magnetic field strength at the gap substantially uniform and high. Further, according to the invention as claimed in claim 2, the steel plate constituting the iron core of the electromagnet has a divided structure, and each divided portion is arranged and joined so that the rolling direction and the direction of the lines of magnetic force are approximately parallel to each other. The iron core structure in item 1 can be easily made.

[0007]

[Embodiment] An embodiment of the present invention will be explained. here,
A case will be described in which the present invention is applied to an iron core of a bending electromagnet of a synchrotron. FIG. 1 shows the side structure of a bending electromagnet to which the present invention is applied. This bending electromagnet 22 is constructed by laminating a large number of silicon steel plates 26 each having an iron core 24 formed in a "U" shape. A reinforcing member 34 made of stainless steel or the like is welded to the outer peripheral corner of the iron core 24 to fix the entire structure. Coils 28 and 30 are attached to the iron core 24.
is wound to create a vertical magnetic field in the gap 32 between the magnetic poles, which provides a horizontal deflection force on the particle beam in the storage ring of the synchrotron located within this gap 32.

One silicon steel plate 26 has a five-part structure diagonally divided at each corner, and these parts are joined together by welding to form one silicon steel plate 26. Each divided portion 26a to 26e is arranged so that the rolling direction 36 is parallel to the direction of the magnetic path.

According to the above configuration, when the coils 28 and 30 are excited, lines of magnetic force 38 are generated in the iron core 24. In this case, in each divided portion 26a to 26e, the rolling direction and the line of magnetic force 38
Since the directions are substantially parallel, the magnetic permeability is high and substantially uniform throughout the magnetic path. Therefore, the leakage magnetic field is reduced, the magnetic field strength within the gap 32 is high and substantially uniform, and a strong and stable deflection force can be applied to the particle beam.

An embodiment of the manufacturing process for the iron core 24 shown in FIG. 1 will be described with reference to FIG. 4. (2) Punching out each of the divided portions 26a to 26e from the rolled silicon steel plate 40 with the direction of the magnetic path and the rolling direction matching each other. ■ Arrange the punched divided portions 26a to 26e in a "U" shape and attach each corner 42.
are joined by spot welding or the like to make one silicon steel plate 26. Then, the required number of silicon steel plates 26 are made in the same process. Note that the protruding portion of the spot weld is ground down with a grinder to make it flat. ■ These silicon steel plates 26 are stacked and arranged in a fan shape along the shape of the deflection part of the synchrotron storage ring, and the reinforcing member 34 of L-shaped steel is applied to the outer peripheral corner, and the side part 34a is attached to each silicon steel plate 26. By welding, the silicon steel plates 26 are fixed to form the iron core 24. Then, coils 28 and 30 (FIG. 1) are wound around this to complete the deflection electromagnet.

[0011]

[Modification example] In the above embodiment, the silicon steel plate 26 was divided into five parts, but as shown in FIG.
It is also possible to have a nine-part structure consisting of a to 26i. In this case, the corner divided portions 26b, 26d, 26f, 26
h forms the rolling direction 36 in an oblique direction along the magnetic path. In addition, various numbers of divisions and various division positions are possible.

Further, in the above embodiment, the present invention is applied to a bending electromagnet of a synchrotron, but it can be applied to various other electromagnets. Furthermore, the steel plate is not limited to silicon steel plates, and various magnetic steel plates can be used.

[0013]

As explained above, according to the invention as set forth in claim 1, the steel plate constituting the iron core of the electromagnet is formed so that its rolling direction is approximately parallel to the direction of the lines of magnetic force. The magnetic permeability is substantially constant and high in each portion of the gap, and the leakage field is reduced, making it possible to make the magnetic field strength in the gap substantially uniform and high. Further, according to the invention as claimed in claim 2, the steel plate constituting the iron core of the electromagnet has a divided structure, and each divided portion is arranged and joined so that the rolling direction and the direction of the lines of magnetic force are approximately parallel to each other. The iron core structure in item 1 can be easily made.

[Brief explanation of drawings]

FIG. 1 is a side view showing an embodiment of the present invention.

FIG. 2 is a side view showing a conventional iron core structure.

FIG. 3 is a characteristic diagram showing changes in magnetic permeability depending on the angle between the rolling direction of a silicon steel plate and the lines of magnetic force.

4 is a process diagram showing an example of the manufacturing process of the iron core of FIG. 1. FIG.

FIG. 5 is a side view showing another embodiment of the invention.

[Explanation of symbols]

22 Bending electromagnet (electromagnet) 24 Iron core 26 Silicon steel plate (steel plate) 26a-26i Divided part 36 Rolling direction 38 Lines of magnetic force

Claims (2)

[Claims] 1. An iron core structure for an electromagnet, in which a steel plate constituting the iron core of the electromagnet is formed so that its rolling direction is approximately parallel to the direction of lines of magnetic force. 2. An iron core structure for an electromagnet, in which a steel plate constituting the iron core of the electromagnet has a divided structure, and each divided portion is arranged and joined so that the rolling direction and the direction of the lines of magnetic force are substantially parallel.