JP2023113446A - Electromagnet for charged particle accelerator - Google Patents

Abstract

To provide an electromagnet for a charged particle accelerator which facilitates positioning of a coil with respect to a yoke and facilitates assembly work.SOLUTION: An electromagnet 10 for a charged particle accelerator includes a yoke 20, and a coil member 30 located at least partially within the yoke 20. The coil member 30 includes an insulator 34, and a coil 32 embedded in the insulator 34. The coil member 30 is provided with a protruding portion 36 positioned within the yoke 20 and protruding toward the yoke 20.SELECTED DRAWING: Figure 2

Description

The present invention relates to electromagnets for charged particle accelerators.

US Pat. No. 5,300,000 discloses a bending magnet for use in a synchrotron storage ring.

The bending electromagnet of Patent Document 1 has a pair of iron cores (upper and lower iron cores, yoke) and a pair of coils (upper and lower coils). There is a one-to-one correspondence between the iron core and the coil. A groove is formed in each of the iron cores. Each coil is mated with a corresponding iron core such that a portion of the coil lies within the groove.

During operation of the bending electromagnet, an electromagnetic force acts on the coil. An insulator is packed between the core and the coil in the groove so that the coil will not move due to electromagnetic force.

Japanese Utility Model Laid-Open No. 3-86600

In the bending electromagnet of Patent Literature 1, each of the coils must be placed at an appropriate position within the corresponding groove of the iron core. Here, it is difficult to adjust the position of the coil with respect to the core after the insulator is stuffed into the groove of the core. Therefore, the position of the coil with respect to the core must be appropriate before and after the insulator is stuffed into the groove. Therefore, the bending electromagnet of Patent Literature 1 has problems in that the assembly work is complicated and it is difficult to properly position the coil with respect to the iron core.

SUMMARY OF THE INVENTION It is an object of the present invention to provide an electromagnet for a charged particle accelerator, in which the coil can be easily positioned with respect to the yoke and the assembling work can be easily performed.

The present invention provides, as a first electromagnet for charged particle accelerator, an electromagnet for charged particle accelerator comprising a yoke and a coil member positioned at least partially within the yoke,
The coil member includes an insulator and a coil embedded in the insulator,
Provided is an electromagnet for a charged particle accelerator, wherein the coil member is provided with a protruding portion positioned within the yoke and protruding toward the yoke.

Further, the present invention is a first electromagnet for a charged particle accelerator as a second electromagnet for a charged particle accelerator,
An electromagnet for a charged particle accelerator is provided in which a reinforcing member is embedded inside the protrusion.

Further, the present invention provides a second electromagnet for a charged particle accelerator as a third electromagnet for a charged particle accelerator,
The reinforcing member provides an electromagnet for a charged particle accelerator made of fiber tape.

Further, according to the present invention, as a fourth electromagnet for charged particle accelerator, any one of the first to third electromagnets for charged particle accelerator,
The charged particle accelerator electromagnet further comprises a positioning block,
The positioning block is fixed to the yoke so as to be adjacent to the protrusion of the coil member, and provides an electromagnet for a charged particle accelerator that restricts movement of the protrusion of the coil.

The present invention also provides a fifth electromagnet for a charged particle accelerator, which is any one of the first to fourth electromagnets for a charged particle accelerator,
The electromagnet for a charged particle accelerator is a bending electromagnet,
The coil has a shape consisting of two parallel sides and two connecting parts connecting the two sides at both ends,
The projecting portion provides an electromagnet for a charged particle accelerator projecting from two parallel sides of the coil toward the yoke.

Further, according to the present invention, as a sixth electromagnet for charged particle accelerator, any one of the first to fifth electromagnets for charged particle accelerator,
The insulator of the coil member affects the electromagnet for charged particle accelerator, which is epoxy resin or polyimide resin.

According to one aspect of the present invention, a coil member used in an electromagnet for a charged particle accelerator is provided with a protruding portion positioned within the yoke and protruding toward the yoke. The protrusion facilitates positioning of the coil member with respect to the yoke. In addition, it prevents or suppresses movement of the coil member with respect to the yoke, thereby facilitating the work of assembling the electromagnet for a charged particle accelerator.

1 is a perspective view showing an electromagnet for a charged particle accelerator according to one embodiment of the present invention; FIG. FIG. 2 is a plan view showing the electromagnet for a charged particle accelerator of FIG. 1; The inside of the yoke is shown by dashed lines. FIG. 3 is a sectional view taken along the line AA showing the electromagnet for charged particle accelerator of FIG. 2; FIG. 3 is a cross-sectional view taken along the line BB showing the electromagnet for charged particle accelerator of FIG. 2; FIG. 3 is a plan view showing a lower yoke and a lower coil member included in the electromagnet for charged particle accelerator of FIG. 2; The internal configuration of the lower coil member is indicated by dashed lines.

Referring to FIG. 1, a charged particle accelerator electromagnet 10 according to one embodiment of the present invention includes a yoke 20 and a coil member 30. As shown in FIG. Coil member 30 is located partially within yoke 20 . However, the present invention is not limited to this. The coil member 30 may be positioned entirely within the yoke 20 . In other words, the coil member 30 may be at least partially located within the yoke 20 .

As shown in FIG. 1 , the yoke 20 has an upper yoke 22 and a lower yoke 24 . The upper yoke 22 is composed of a top plate yoke 221 and a pair of upper yokes 223 and 225 . Also, the lower yoke 24 is composed of a bottom plate yoke 241 and a pair of lower yokes 243 and 245 . The top plate yoke 221, the upper yokes 223 and 225, the lower yokes 243 and 245, and the bottom plate yoke 241 are joined together and integrated. However, the present invention is not limited to this. Yoke 20 may, for example, be constructed in one piece or in two pieces.

As shown in FIG. 1, the coil member 30 includes an upper coil member 301 and a lower coil member 303. As shown in FIG. In the present embodiment, upper coil member 301 and lower coil member 303 have the same configuration and are arranged so that their winding axes are aligned. In the present embodiment, the winding shafts of upper coil member 301 and lower coil member 303 extend vertically. In this embodiment, the vertical direction is the Z direction. The +Z direction is upward and the -Z direction is downward. However, the present invention is not limited to this. The upper coil member 301 and the lower coil member 303 may be configured symmetrically with respect to a plane orthogonal to the winding axis.

As shown in FIGS. 2-4, the charged particle accelerator electromagnet 10 further comprises pole pieces 26,28. The top pole piece 26 is fixed to the top plate yoke 221 and the bottom pole piece 28 is fixed to the bottom plate yoke 241 . The top pole piece 26 corresponds to the top coil member 301 and the bottom pole piece 28 corresponds to the bottom coil member 303 . Specifically, when viewed along the winding axis of the coil member 30 , the upper pole piece 26 is located inside the upper coil member 301 and the lower pole piece 28 is located inside the lower coil member 303 . There may be a gap of about 5 mm between the upper coil member 301 and the upper pole piece 26 . Similarly, there may be a gap of about 5 mm between the lower coil member 303 and the lower pole piece 28 .

As shown in FIG. 2, the coil member 30 has a racetrack shape elongated in the front-rear direction and is slightly curved. In this embodiment, the front-rear direction is the Y direction. As understood from the shape of the coil member 30, the electromagnet 10 for charged particle accelerator is a bending electromagnet used in a circular accelerator.

As shown in FIG. 2 , the coil member 30 is provided with a plurality of projections 36 . These protrusions 36 are located within the yoke 20 and protrude toward the yoke 20 . Specifically, the protrusions 36 are provided on the upper coil member 301 and the lower coil member 303, respectively. In the present embodiment, the number of projections 36 provided on upper coil member 301 is six. Similarly, the number of protrusions 36 provided on the lower coil member 303 is also six. However, the present invention is not limited to this. The number and arrangement of protrusions 36 may be arbitrarily set according to the size and shape of coil member 30 .

As understood from FIG. 2, there is almost no gap between the projection 36 provided on the coil member 30 and the yoke 20. As shown in FIG. Specifically, there is only a gap of about 1 mm between the projecting portion 36 and the yoke 20 . As described above, since the projecting portion 36 and the yoke 20 are close to each other, it is not necessary to dispose a filler (insulator) in the gap between the coil member 30 and the yoke 20 . This makes it possible to easily position the coil member 30 with respect to the yoke 20 in the lateral direction, thereby facilitating the assembly work of the electromagnet 10 for a charged particle accelerator. In this embodiment, the horizontal direction is the X direction.

As shown in FIG. 2 , the charged particle accelerator electromagnet 10 further includes a plurality of positioning blocks 38 . The positioning block 38 is provided on the yoke 20 so as to be adjacent to the projecting portion 36 of the coil member 30 . In this embodiment, four positioning blocks 38 are provided for each of the upper coil member 301 and the lower coil member 303 . Specifically, the positioning block 38 is provided further outside the projecting portion 36 located outside in the front-rear direction. Each positioning block 38 is a metal block, for example, and is screwed to the yoke 20 . However, the present invention is not limited to this. The positioning block 38 may be formed integrally with the yoke 20 . Also, the positioning block 38 may be provided inside the protruding portion 36 positioned outside in the front-rear direction. In any case, the number and arrangement of positioning blocks 38 may be arbitrarily set according to the configuration of coil member 30 .

As can be understood from FIG. 2, the positioning block 38 restricts movement of the projecting portion 36 in the front-rear direction, thereby restricting movement of the coil member 30 . Thereby, the coil member 30 can be easily positioned in the front-rear direction, and the assembly work of the electromagnet 10 for a charged particle accelerator can be facilitated.

As shown in FIGS. 3 and 4, the coil member 30 has a coil 32 and an insulator 34 . Specifically, the upper coil member 301 and the lower coil member 303 are provided with an upper coil 321 and a lower coil 323, respectively. Each of the upper coil 321 and the lower coil 323 is, for example, wound with a copper wire whose outer periphery is covered with a glass tape. Each of the upper coil 321 and the lower coil 323 is embedded in the insulator 34 . In other words, each of the upper coil 321 and the lower coil 323 is covered with the insulator 34 . The insulator 34 is, for example, epoxy resin or polyimide resin. Each of the upper coil member 301 and the lower coil member 303 can be manufactured, for example, by placing the upper coil 321 or the lower coil 323 in a mold and performing insert molding using resin.

As shown in FIGS. 3 and 4 , the upper coil member 301 is housed within the upper yoke 22 and restricted from moving vertically by the support 40 . Similarly, the lower coil member 303 is housed within the lower yoke 24 and described for vertical movement by the support 40 .

As can be seen from FIG. 5, the lower coil 323 of the lower coil member 303 has long side portions 331 and 333 extending substantially in the front-rear direction, and a pair of connecting portions 335 and 337 connecting both ends thereof. are doing. The long sides 331 and 333 are two sides parallel to each other. The long sides 331, 333 are curved and thereby differ in length from each other. The upper coil member 301 is similar to the lower coil member 303 .

As shown in FIG. 5, the lower coil member 303 further has a plurality of reinforcing members 361. As shown in FIG. In this embodiment, the number of reinforcing members 361 is six. Each of the reinforcing members 361 is provided on the outer peripheral side surface of the long side portions 331 and 333 that are two parallel sides of the lower coil 323 and protrudes toward the yoke 20 . The upper coil member 301 is configured similarly to the lower coil member 303 .

As understood from FIGS. 5 and 2, the reinforcing member 361 is for forming the projection 36. As shown in FIG. That is, the projecting portion 36 is composed of the reinforcing member 361 and a portion of the insulator 34 covering it. In other words, the reinforcing member 361 is embedded inside each of the protrusions 36 . When forming the insulator 34 of the upper coil member 301 , the reinforcing member 361 is placed in the mold together with the upper coil 321 and integrally formed with the insulator 34 together with the upper coil 321 .

When the upper coil member 301 (or the lower coil member 303) is arranged in the upper yoke 22 (or the lower yoke 24), the reinforcing member 361 is arranged so that the protruding portion 36 is attached to the upper yoke 22 (or the lower yoke 24). Even if it collides, it needs to be strong enough not to break. In addition, the reinforcing member 361 requires a strength that makes it difficult for the upper coil member 301 (or the lower coil member 303) to deform when the electromagnet 10 for a charged particle accelerator is used. As such a reinforcing member 361, a bundled or folded glass fiber tape or Nomex (registered trademark) can be used. However, the present invention is not limited to this. The reinforcing member 361 may be composed of another member such as a resin block, or may be replaced by the insulator 34 .

As described above, the coil member 30 of the electromagnet 10 for a charged particle accelerator according to this embodiment includes the projecting portion 36 . This makes it possible to easily position the coil member 30 with respect to the yoke 20 . Thus, according to the present embodiment, it is possible to facilitate the work of assembling the electromagnet 10 for a charged particle accelerator. In addition, when the coil member 30 tries to expand in the lateral direction due to the force acting on the coil member 30 during use of the electromagnet 10 for a charged particle accelerator, the protrusion 36 abuts against the yoke 20 to prevent its deformation. can be done. In order to efficiently suppress deformation, the projecting portion 36 that suppresses deformation of the coil member 30 is preferably provided at a position where the amount of deformation of the coil member 30 is the largest. For example, when the coil member 30 has a racetrack shape, the deformation of the coil member 30 can be effectively suppressed by providing the projecting portion 36 at the central portion in the front-rear direction of the long side portions 331 and 333 . can.

As described above, the present invention has been described with reference to several embodiments, but the present invention is not limited to the above embodiments, and various modifications and changes can be made without departing from the scope of the present invention. is possible. For example, the present invention is applicable to a combination of a coil member and a yoke having a single coil. Moreover, the present invention is applicable not only to bending electromagnets, but also to electromagnets for other uses, such as converging electromagnets (magnetic lenses). The present invention is also applicable to electromagnets with circular coils and electromagnets with air-core coils. Furthermore, the present invention is applicable not only to a racetrack-shaped coil, but also to an electromagnet having a saddle-shaped coil in which both ends of the racetrack-shaped coil are bent in the direction of the winding axis. An example of a saddle coil is disclosed in Japanese Patent No. 2529492.

10 electromagnet for charged particle accelerator 20 yoke 22 upper yoke
221 top plate yoke 223 , 225 upper yoke 24 lower yoke 241 bottom plate yoke 243 , 245 lower yoke 26 upper magnetic pole piece 28 lower magnetic pole piece 30 coil member 301 upper coil member 303 lower coil member 32 coil 321 upper coil 323 Lower coil 331, 333 Long side 335, 337 Connecting part 34 Insulator 36 Protruding part 361 Reinforcing member 38 Positioning block 40 Supporting tool

Claims (6)

An electromagnet for a charged particle accelerator, comprising a yoke and a coil member located at least partially within the yoke,
The coil member includes an insulator and a coil embedded in the insulator,
An electromagnet for a charged particle accelerator, wherein the coil member is provided with a protruding portion positioned within the yoke and protruding toward the yoke. The electromagnet for a charged particle accelerator according to claim 1,
An electromagnet for a charged particle accelerator, wherein a reinforcing member is embedded inside the projecting portion. The electromagnet for a charged particle accelerator according to claim 2,
The electromagnet for a charged particle accelerator, wherein the reinforcing member is made of a fiber tape. The electromagnet for a charged particle accelerator according to any one of claims 1 to 3,
The charged particle accelerator electromagnet further comprises a positioning block,
The positioning block is fixed to the yoke so as to be adjacent to the protrusion of the coil member, and restricts movement of the protrusion of the coil. The electromagnet for a charged particle accelerator according to any one of claims 1 to 4,
The electromagnet for a charged particle accelerator is a bending electromagnet,
The coil has a shape consisting of two parallel sides and two connecting parts connecting the two sides at both ends,
The electromagnet for a charged particle accelerator, wherein the protrusions protrude from two parallel sides of the coil toward the yoke. The electromagnet for a charged particle accelerator according to any one of claims 1 to 5,
The electromagnet for a charged particle accelerator, wherein the insulator of the coil member is epoxy resin or polyimide resin.

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