JP2000252100A - Deflecting electromagnet and its manufacture - Google Patents

Abstract

PROBLEM TO BE SOLVED: To form an efficient effective magnetic field region corresponding to charged particle beam width and to accurately set an edge angle as occasion demands by changing stacking structure of electromagnetic steel plates. SOLUTION: This deflecting electromagnet sets an edge angle α by inclining electromagnetic steel plates 2a, 2b in charged particle beam outlet and inlet 6A, 6B of an electromagnet main body 1 by a specified angle to the perpendicularly crossing surface with the beam axis of a charged particle beam 7, other electromagnetic steel plates are stacked so as to match with a designed orbit 8 through which the charged particle beam is passed by shifting one by one in parallel to the electromagnetic steel plates 2A, 2B in the charged particle beam outlet and inlet 6A, 6B, and thereby, magnetic pole width H is made wider in the central part of the designed orbit 8 than the charged particle beam outlet and inlet 6A, 6B sides.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a bending electromagnet for deflecting a charged particle beam, and more particularly to an effective magnetic field region for the shape and width of the charged particle beam by the way of stacking electromagnetic steel sheets constituting an electromagnet body. It relates to a bending electromagnet.

[0002]

2. Description of the Related Art FIG. 5 is a view showing a conventional bending electromagnet disclosed in, for example, JP-A-01-194300. The bending electromagnet includes a pair of magnetic poles 104 facing each other via a predetermined gap 105 and a yoke 106 connecting the pair of magnetic poles 104.
And a coil 103 for generating a uniform magnetic field in the gap 105 and bending the trajectory of the charged particle beam B passing through the gap 105 into an arc having a center of curvature.

The cross-sectional shape of the magnetic pole 104 of the bending electromagnet is the same regardless of the deflection angle, and the effective magnetic field area is an arc having a constant width. When the width of the charged particle beam B bent by the bending electromagnet is constant in the electromagnet main body 101 or the width of the charged particle beam changes, the maximum charged particle beam width in the electromagnet main body 101 is larger than the width of the effective magnetic field region. Applicable for small cases.

[0004]

In the conventional bending electromagnet, when the charged particle beam width changes, when the magnetic pole width is designed in accordance with the maximum charged particle beam width, the entire electromagnet body 101 becomes large. Therefore, not only is it necessary to increase the installation location of the bending electromagnet, but also the material cost of the electromagnetic steel sheet 102 and the material cost of the coil 103 increase, and the amount of power required for the coil 103 also increases.

As described above, in a conventional bending electromagnet having a constant magnetic pole width determined by the maximum charged particle beam width,
Since a wide effective magnetic field region is given over the entire trajectory of the charged particle beam B, when the charged particle beam width changes remarkably in the electromagnet main body 101, a useless magnetic field region is generated at a small charged particle beam width. As a result, there is a problem that the electromagnet main body 101 becomes large.

When an edge angle is required to converge the charged particle beam B, an electromagnetic steel plate 102 is laminated in order to form an angle corresponding to the edge angle at the entrance / exit of the charged particle beam of the electromagnet body 101. It becomes necessary to cut off the entrance and exit of the charged particle beam of the electromagnet body 1. Here, the edge angle is an intersection angle between a plane orthogonal to the beam axis of the charged particle beam and an end surface of the electromagnet main body 1 on the entrance / exit side of the charged particle beam. However, since the amount of change in the magnetic field intensity always increases at the entrance and exit of the charged particle beam, even a small error greatly affects the edge effect on the charged particle beam B, and in the conventional bending electromagnet in which the entrance and exit of the charged particle beam are cut off. However, there is a problem that the accuracy of the edge angle cannot be sufficiently obtained.

Further, in this bending electromagnet, the effective magnetic field region has the same width on the deflection center side and on the outside with the design trajectory as a boundary, but the required effective magnetic field region is the deflection center of the charged particle beam B to be deflected. If the side and the outside are different, the electromagnet body 101 is more than necessary to match the effective magnetic field area.
There was also a problem that had to be enlarged.

SUMMARY OF THE INVENTION An object of the present invention is to solve the above-described problems. The charged particle beam width is different when the width of the charged particle beam is greatly different between the entrance and exit of the bending electromagnet and the central portion. It is possible to form an effective effective magnetic field region according to the conditions, and the edge angle is not formed by cutting, and the edge angle can be adjusted with high precision as necessary by changing the laminated structure of the electromagnetic steel sheet It is an object to provide a deflectable electromagnet.

[0009]

According to a first aspect of the present invention, there is provided a bending electromagnet having a pair of magnetic poles facing each other via a gap, a yoke connecting the pair of magnetic poles, and laminating a large number of magnetic steel sheets. An electromagnet main body configured as described above, and a coil provided in the electromagnet main body to generate a magnetic field in the gap to bend a trajectory of a charged particle beam passing through the gap into an arc shape having a center of curvature, and the electromagnet main body is By tilting the magnetic steel sheet at the entrance and exit of the charged particle beam at a predetermined angle with respect to the plane orthogonal to the beam axis of the charged particle beam, an edge angle for converging the charged particle beam is formed, and the electromagnetic steel sheet at the entrance and exit of the charged particle beam is formed. The other magnetic steel sheets are arranged in parallel and stacked one by one in accordance with the arc-shaped trajectory through which the charged particle beam should pass, and the In which the central side of the track is greater than the deflection radial pole width through the rate center charged particle beam entrance side.

A bending electromagnet according to a second aspect of the present invention has a pair of magnetic poles facing each other via a gap and a yoke connecting the pair of magnetic poles, and is formed by laminating a large number of electromagnetic steel plates. And a coil provided on the electromagnet main body to generate a magnetic field in the gap to bend a trajectory of a charged particle beam passing through the gap into an arc shape having a center of curvature. The steel sheet is arranged in parallel with the plane orthogonal to the beam axis of the charged particle beam, and the other magnetic steel sheets are arranged in parallel with the electromagnetic steel sheet at the entrance and exit of the charged particle beam in an arc-shaped trajectory through which the charged particle beam should pass. The magnetic pole width in the deflection radial direction passing through the center of curvature of the orbit is charged more than the central part of the orbit of the charged particle beam. In which the child beam entrance side is larger.

Further, in the bending electromagnet according to claim 3, the electromagnet main body has a deflection angle of ２ and is joined to each other on a plane perpendicular to the beam axis of the charged particle beam. It is composed of a second laminated block.

According to a fourth aspect of the present invention, there is provided a bending electromagnet having a pair of magnetic poles facing each other via a gap, a yoke connecting the pair of magnetic poles, and a multi-layered electromagnetic steel plate. And a coil provided in the electromagnet main body to generate a magnetic field in the gap to bend the trajectory of the charged particle beam passing through the gap into an arc shape having a center of curvature, and the electromagnet main body allows the charged particle beam to pass therethrough. The magnetic pole width in the deflection radial direction passing through the center of curvature of the orbit is shifted from the entrance / exit side of the charged particle beam to the center of the orbit of the charged particle beam by laminating one by one according to the orbit of the arc to be stacked. As well as
The effective magnetic field area of the electromagnet body is shifted with respect to the trajectory of the charged particle beam by shifting the center line of the electrode of each magnetic steel sheet with respect to the trajectory of the charged particle beam with respect to the trajectory of the charged particle beam. Is what it is.

In the bending electromagnet according to the fifth aspect, shims for increasing the magnetic flux density at both ends are provided at both ends of the magnetic poles in the deflection radial direction passing through the center of curvature of the orbit.

[0014] Further, a method of manufacturing a bending electromagnet according to claim 6 includes a step of forming blocks by laminating electromagnetic steel sheets;
Cutting the block so as to have a cutting plane perpendicular to the beam axis of the charged particle beam to form a first laminated block and a second laminated block; and a cut plane of the first laminated block. And joining the cut surface of the second laminated block to the cut surface of the second laminated block.

[0015]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiment 1 FIG. 1 shows a bending electromagnet according to Embodiment 1 of the present invention. The first embodiment is applied to a case where the bending electromagnet has an edge focusing effect at the entrance and exit of the charged particle beam 7. That is, this bending electromagnet has a pair of magnetic poles 5 and 5 facing each other via a predetermined gap 6 and a yoke 21 connecting the pair of magnetic poles 5 and 5, and a large number of electromagnetic steel sheets 2 are laminated. The trajectory of the charged particle beam 7 passing through the gap 6 by generating a uniform magnetic field in the formed electromagnet main body 1 and the gap 6 between the magnetic poles 5 provided in the electromagnet main body 5 is a circle having the center of curvature 4. And a coil 3 bent in an arc shape.

The electromagnet main body 1 converges the charged particle beam 7 by tilting the magnetic steel plates 2A and 2B at the charged particle beam entrances 6A and 6B with respect to a plane orthogonal to the beam axis of the charged particle beam 7. Are formed at the entrance and exit of the charged particle beam 6A, 6B.
It is configured by stacking another electromagnetic steel plate 2 of the same shape in parallel with 2B so as to be shifted one by one in accordance with an arc-shaped design trajectory 8 through which the charged particle beam 7 passes. By employing this laminating method, the magnetic pole width H in the deflection radial direction passing through the center of curvature 4 of the design trajectory 8 of the charged particle beam 7 (when the magnetic pole width W when viewed from the direction perpendicular to the electromagnetic steel plate 2) To H
= Wcos (θ− (β / 2−α)). However,
θ is the angle between the mating surface 11 and the radial direction of the deflection passing through the center of curvature 4. ) Are charged particle beam entrances 6A and 6B
The central portion of the design trajectory 8 of the charged particle beam 7 is larger than the side.

In the electromagnet main body 1, the electromagnetic steel sheets 2 are laminated to the reference electromagnetic steel sheets 2A and 2B on the inlet 6A side and the outlet 6B side of the charged particle beam until they correspond to 1/2 of the deflection angle β. It is composed of two first laminate blocks 1A and second laminate blocks 1B.
The first laminated block 1A and the second laminated blocks 1A and 1B are joined at a center point of the entire design trajectory 8 at a mating surface 11 cut at a plane perpendicular to the design trajectory 8.

The magnetic poles 5, 5 have arc portions formed at both ends in the deflection radial direction. The central region inside the arc portion is the effective magnetic field region 9 in which the error of the magnetic field generated between the gaps 6 is within the range of the accelerator design value. The electromagnetic steel sheet 2 is shown in FIG.
As shown in FIG. 1B, the sheet is a thin plate having an H-shaped hole formed in the center. In FIG. 1A, the intervals are roughly indicated by dotted lines. That is, the electromagnetic steel sheet 2 is configured such that the yoke 21 forms a rectangular frame, and the magnetic poles 5, 5 project between the opposing sides thereof. At the center of each electromagnetic steel plate 2, a magnetic pole reference line 10 representing a position where the center position of the magnetic pole 5 is aligned with the design trajectory 8 is formed.

Next, a procedure for assembling the electromagnet body 1 of the bending electromagnet according to the first embodiment will be described. First, the magnetic steel sheets 2A, 2B at the charged particle beam entrances 6A, 6B are inclined with respect to the design trajectory 8 so as to have a predetermined edge angle α,
The magnetic pole reference line 10 is arranged on the design trajectory 8.
Next, other magnetic steel sheets 2 having the same shape as the reference magnetic steel sheets 2A, 2B are laminated by bonding or welding in parallel to the magnetic steel sheets 2A, 2B of the charged particle beam entrances 6A, 6B. At that time, the magnetic pole reference lines 10 are stacked so as to match the design trajectory 8. The lamination of the magnetic steel sheets 2 is performed until the magnetic steel sheets 2 correspond to 1/2 of the deflection angle β of the bending electromagnet. After forming two sets of blocks of this electromagnetic steel sheet, the portions of the charged particle beam entrances 6A and 6B of each block on the opposite side to the electromagnetic steel sheets 2A and 2B are cut, and the design trajectory 8 is designed at the center point of the entire area of the design trajectory 8. 8 and a first laminated block 1A and a second laminated block 1B having a mating surface 11 which is
To form Then, the first laminated block 1A and the second
The laminated block 1B is bonded or welded on the mating surface 11 to manufacture the electromagnet body 1. In the electromagnet body 1 thus manufactured, the magnetic pole width H in the deflection radial direction becomes maximum at the center of the design trajectory 8 of the charged particle beam 7, and the entrances 6A, 6
It becomes narrower in the direction B.

When a bending electromagnet is manufactured, since the electromagnetic steel plate 2 is formed by a thin plate having an H-shaped hole formed in the center as described above, the coil is not used in the electromagnet body 1 manufactured as described above. 3 is difficult to incorporate. Then, the left and right yokes 21 connecting the pair of electrodes 5 and 5 are cut up and down, and the first and second stacked blocks 1 are cut.
Also for A and 1B, four laminated blocks which are further divided up and down are formed, and the coil 3 is incorporated in the electromagnet main body 1.

In the present embodiment, the magnetic steel sheet 2 is
Although it has a shape, a C-shaped electromagnetic steel sheet may be used in which the yoke connecting the pair of electrodes is located only on one side of the left and right sides of the electrode, as in the related art. In this case, the laminated block 1
It is not necessary to divide A and 1B up and down.

Next, the operation of the bending electromagnet having the above configuration will be described. When a current is applied to the coil 3, a magnetic field is generated in the yoke 1 and a uniform magnetic field is generated in the gap 6. The charged particle beam 7 receives a uniform magnetic field generated in the gap 6 and passes through an arc-shaped design trajectory 8 having a center of curvature 4. That is, the charged particle beam 7 travels in the effective magnetic field region 9 in the gap 6. Since the width of the effective magnetic field region 9 of the deflection electromagnet in the deflection radial direction is maximum at the center of the electromagnet and minimum at the electromagnet entrances and exits 6A and 6B, the charged particle beam width is maximum at the center of the electromagnet and minimum at the electromagnet entrances and exits 6A and 6B. In this case, the effective magnetic field region 9 is used efficiently. Further, in this case, cutting processing is not required to form an edge angle, and a highly accurate edge focusing effect can be obtained.

Next, another embodiment of the present invention will be described. In the following Embodiments 2 to 4, only different points from Embodiment 1 will be described, and the same components will be denoted by the same reference numerals and description thereof will be omitted.

Embodiment 2 FIG. FIG. 2 shows a bending electromagnet according to Embodiment 2 of the present invention. This embodiment shows an embodiment having no edge angle unlike the first embodiment. That is, the electromagnetic steel plates 2A, 2B at the charged particle beam entrances 6A, 6B of the electromagnet main body 1 are arranged in parallel with a plane orthogonal to the beam axis of the charged particle beam 7, and the electromagnetic steel plates 2A, 2B at the charged particle beam entrances 6A, 6B. The other electromagnetic steel sheets 2 are stacked one by one in parallel with each other in accordance with the design trajectory 8 through which the charged particle beam should pass, so that the deflection radial direction passing through the center of curvature 4 of the design trajectory 8 of the charged particle beam Is larger on the charged particle beam entrance / exit side than on the central part side of the design trajectory 8 of the charged particle beam 7.

In the first embodiment, the electromagnet doorway 6
Although the case where the edge angle α is formed by laminating the magnetic steel sheets 2A and 2B of A and 6B in parallel with each other as a reference has been described, in the second embodiment, the charged particle beams are charged at the charged particle beam entrances 6A and 6B. Electromagnetic steel plates 2A and 2B serving as references are provided in a plane perpendicular to the axis, and are laminated in the same manner as in the first embodiment. In this way, the charged particle beam 7 having a large width at the charged particle beam entrances 6A and 6B and having a small width at the center of the electromagnet can be used as a bending electromagnet suitable for a case where an edge angle is not required.

The procedure for assembling the electromagnet body 1 of the bending electromagnet is the same as in the first embodiment. That is, after forming two sets of electromagnetic steel sheets in which the electromagnetic steel sheets 2 are stacked to correspond to 1/2 of the deflection angle β of the bending electromagnet, the magnetic steel sheets 2 of the charged particle beam entrances 6A and 6B of each block are formed.
A first laminated block 1A and a second laminated block 1B each having a mating surface 11 which is cut at a portion opposite to A and 2B and which is a vertical surface of the design trajectory 8 at a central point of the entire area of the design trajectory 8. To form Thereafter, the first laminated block 1A and the second laminated block 1B are bonded or welded on the mating surface 11 to manufacture the electromagnet body 1.

Embodiment 3 FIG. 3 shows a bending electromagnet according to Embodiment 3 of the present invention. Embodiment 3
In this example, the electromagnetic steel plate 2C at the center of the electromagnet main body 1 was installed in a plane perpendicular to the design track 8, and another electromagnetic steel plate 2 (having the same shape as the electromagnetic steel plate 2C) was laminated in parallel with the electromagnetic steel plate 2C. Things. That is, the electromagnetic steel sheet 2 is moved to the charged particle beam 7.
The charged particle beam 7 is designed so as to be shifted one by one in accordance with the arcuate design trajectory 8 through which the charged particle beam 7 passes at the magnetic pole width H in the deflection radial direction passing through the center of curvature 4 of the designed trajectory 8 of the charged particle beam 7. The center of the orbit 8 is larger than the charged particle beam entrances 6A and 6B. The center reference line 10 of the magnetic steel sheet 2 which is the center line of the design trajectory 8 is shifted outward from the center line of the magnetic pole 5 by a constant width δ in the direction of the deflection radius passing through the center of curvature 4. That is, the effective magnetic field region 9 is shifted with respect to the design trajectory 8 of the charged particle beam.

Also in this case, the charged particle beam entrance 6
The effect that the width of the effective magnetic field region 9 is different at the center between A and 6B is the same as that of the first embodiment. Further, it is preferable that the required effective magnetic field region 9 has a different width on the side of the center of curvature 4 and on the outside with respect to the design trajectory 8 of the charged particle beam. When the edge focus effect is required, the charged particle beam may be cut at an arbitrary angle at the entrance / exit 6A, 6B.

Embodiment 4 FIG. 4 shows a bending electromagnet according to Embodiment 4 of the present invention. Embodiment 4
Charges the magnetic steel sheet 2 in a deflection radial direction passing through the center of curvature 4 of the design trajectory 8 of the charged particle beam 7 by stacking the sheets one by one in accordance with the design trajectory 8 of the charged particle beam 7. The central portion of the design trajectory 8 of the particle beam is larger than the charged particle beam entrances 6A and 6B. Shims 12 for increasing the magnetic flux density at both ends are provided at both ends of the magnetic pole 5 in the deflection radial direction passing through the center of curvature 4 of the design orbit 8. The shim 12 is formed in advance at the stage of punching out the electromagnetic steel plate 2.

In the first to third embodiments, the end shape of the magnetic pole is formed in an arc shape so as not to affect the magnetic field distribution generated in the gap 6, but conversely, only the arc-shaped portion has the magnetic pole width. Results. In the present embodiment, although the effect of the higher-order magnetic field components described in the related art is affected, by providing the shims 12 at both ends of the magnetic pole 5 in the deflection radial direction, a wide effective magnetic field can be obtained as in the first to third embodiments. An area can be secured. The influence of the magnetic field higher-order component due to the provision of the shim 12 is corrected so as to reduce the error.

In each of the above embodiments, the track 3 is used as the shape of the coil 3. However, it is needless to say that the coil 3 may have an arbitrary shape such as a saddle.

[0032]

As described above, according to the first aspect of the present invention, a plurality of magnetic steel sheets are laminated with a pair of magnetic poles facing each other via a gap and a yoke connecting the pair of magnetic poles. The configured electromagnet body, comprising a coil provided in the electromagnet body to generate a magnetic field in the gap to bend a trajectory of a charged particle beam passing through the gap into an arc having a center of curvature, the electromagnet body comprising:
By tilting the magnetic steel sheet at the entrance and exit of the charged particle beam at a predetermined angle with respect to the plane perpendicular to the beam axis of the charged particle beam, an edge angle for converging the charged particle beam is formed and the electromagnetic steel sheet at the entrance and exit of the charged particle beam is formed. In parallel, another magnetic steel sheet is laminated and shifted one by one in accordance with the arc-shaped orbit through which the charged particle beam passes, and the magnetic pole width in the deflection radial direction passing through the center of curvature of the orbit is set to the charged particle beam. Since the central portion of the orbit is larger than the entrance / exit side, an effective effective magnetic field region can be provided when the beam width of the charged particle beam is maximum at the center of the electromagnet main body and minimum at the entrance / exit of the electromagnet main body. . Therefore,
A deflection electromagnet suitable for the case where the charged particle beam width changes depending on the deflection angle can be reduced in weight. In addition, since the edge angle is determined by the inclination of the magnetic steel sheet on the entrance and exit side of the charged particle beam, cutting processing is not required to form the edge angle,
A highly accurate edge focus effect can be provided. .

The bending electromagnet according to the second aspect of the present invention includes a pair of magnetic poles facing each other via a gap and a yoke connecting the pair of magnetic poles, and is formed by laminating a large number of electromagnetic steel plates. An electromagnet main body, and a coil provided in the electromagnet main body for generating a magnetic field in the gap to bend a trajectory of a charged particle beam passing through the gap into an arc shape having a center of curvature. The magnetic steel sheet is arranged in parallel with a plane orthogonal to the beam axis of the charged particle beam, and the other magnetic steel sheet is parallel to the magnetic steel sheet at the entrance and exit of the charged particle beam. The magnetic pole width in the deflection radial direction passing through the center of curvature of the orbit is configured to be shifted from the center of the orbit of the charged particle beam. Since the charged particle beam entrance / exit side is large, the beam width of the charged particle beam is maximum at the entrance / exit of the electromagnet main body, is small at the center of the electromagnet main body, and is suitable for a bending electromagnet suitable when an edge angle is not required. .

In the bending electromagnet according to the third aspect of the present invention, the electromagnet main body has a deflection angle of と と も に and is joined to each other on a plane perpendicular to the beam axis of the charged particle beam. Since it is composed of the block and the second laminated block, a bending electromagnet can be easily manufactured.

Further, the bending electromagnet according to the fourth aspect of the invention has a pair of magnetic poles facing each other via a gap and a yoke connecting the pair of magnetic poles, and is formed by laminating a large number of electromagnetic steel plates. An electromagnet main body, and a coil provided in the electromagnet main body to generate a magnetic field in the gap to bend a trajectory of a charged particle beam passing through the gap into an arc shape having a center of curvature, wherein the electromagnet main body includes the charged particle beam. The magnetic pole width in the deflection radial direction passing through the center of curvature of the orbit is changed by laminating one by one in accordance with the arc-shaped orbit through which the arc is to pass. Side and the center line of the electrode of each magnetic steel sheet is shifted by a certain dimension in the direction of the deflection radius passing through the center of curvature of the orbit with respect to the orbit of the charged particle beam. Since the effective magnetic field area of the magnet body is shifted with respect to the trajectory of the charged particle beam, it is suitable when the width of the effective magnetic field area required at the center of curvature and outside the charged particle beam at the design trajectory is different. It is. .

Further, in the bending electromagnet according to the fifth aspect of the present invention, since shims for increasing the magnetic flux density at both ends are provided at both ends of the magnetic pole in the deflection radial direction passing through the center of curvature of the orbit, the width of the magnetic pole can be reduced. A wide effective magnetic field region can be formed.

According to a sixth aspect of the present invention, there is provided a method for manufacturing a bending electromagnet, comprising: forming a block by laminating electromagnetic steel sheets; and forming a block perpendicular to the beam axis of the charged particle beam. The method includes a step of cutting the block to form a first laminated block and a second laminated block, and a step of joining the cut surface of the first laminated block and the cut surface of the second laminated block. The bending electromagnet can be easily manufactured without taking complicated steps.

[Brief description of the drawings]

FIG. 1 (a) is a plan view of a bending electromagnet according to Embodiment 1 of the present invention, and FIG. 1 (b) is a diagram showing an exit side of a charged particle beam of FIG. 1 (a).

FIG. 2 (a) is a plan view of a bending electromagnet according to Embodiment 2 of the present invention, and FIG. 2 (b) is a diagram showing an exit side of the charged particle beam of FIG. 2 (a).

FIG. 3 (a) is a plan view of a bending electromagnet according to Embodiment 3 of the present invention, and FIG. 3 (b) is a diagram showing a center cut end face of the bending electromagnet of FIG. 3 (a).

FIG. 4 (a) is a plan view of a bending electromagnet according to Embodiment 4 of the present invention, and FIG. 4 (b) is a diagram showing a center cut end face of the bending electromagnet of FIG. 4 (a).

5 (a) is a plan view showing a conventional bending electromagnet, and FIG. 5 (b) is a perspective view of the device shown in FIG. 5 (a).

[Explanation of symbols]

1 Electromagnetic body, 1A, 1B laminated block, 2 electromagnetic steel sheet, 2A electromagnetic steel sheet at charged particle beam entrance, 2B electromagnetic steel sheet at charged particle beam exit, 3 coil, 4 center of curvature, 5 magnetic poles, 6 gap, 6A charged particle beam entrance , 6B charged particle beam outlet, 7 charged particle beam,
8 Design trajectory, 9 Effective magnetic field area, 10 magnetic pole reference line, 1
1 mating surface, 12 shims, α edge angle, H magnetic pole width, β deflection angle.

Claims (6)

[Claims] 1. An electromagnet main body comprising a pair of magnetic poles facing each other via a gap and a yoke connecting the pair of magnetic poles, and configured by laminating a large number of electromagnetic steel plates, and an electromagnet main body provided on the electromagnet main body. A coil that generates a magnetic field in the gap and bends the trajectory of the charged particle beam passing through the gap into an arc shape having a center of curvature, wherein the electromagnet main body moves the magnetic steel sheet at the entrance and exit of the charged particle beam through the beam axis of the charged particle beam. A circle at which the charged particle beam should pass through another electromagnetic steel sheet in parallel with the electromagnetic steel sheet at the entrance and exit of the charged particle beam while forming an edge angle for converging the charged particle beam by inclining the charged particle beam by a predetermined angle with respect to a plane orthogonal to The stack is formed by shifting one by one in accordance with the arc-shaped orbit, and the magnetic pole width in the deflection radial direction passing through the center of curvature of the orbit is determined by the output of the charged particle beam. Bending magnet central portion of the track is larger than the port side. 2. An electromagnet main body comprising a pair of magnetic poles facing each other via a gap and a yoke connecting the pair of magnetic poles, and formed by laminating a large number of electromagnetic steel plates, and an electromagnet main body provided on the electromagnet main body. A coil that generates a magnetic field in the gap and bends the trajectory of the charged particle beam passing through the gap into an arc shape having a center of curvature, wherein the electromagnet main body is configured such that the magnetic steel sheet at the entrance and exit of the charged particle beam is moved along with the beam axis of the charged particle beam. The other magnetic steel sheets are arranged in parallel with the orthogonal plane of the charged particle beam entrance and exit parallel to the magnetic steel sheet at the entrance and exit of the charged particle beam, and are stacked one by one in accordance with an arc-shaped orbit through which the charged particle beam should pass. The magnetic particle width in the deflection radial direction passing through the center of curvature of the orbit is larger on the charged particle beam entrance / exit side than on the central side of the charged particle beam orbit. Deflection electromagnet that. 3. The electromagnet body includes a first laminated block and a second laminated block having a deflection angle of １ ／ and joined to each other on a plane perpendicular to the beam axis of the charged particle beam. The bending electromagnet according to claim 1. 4. An electromagnet body having a pair of magnetic poles facing each other via a gap and a yoke connecting the pair of magnetic poles, and configured by laminating a large number of electromagnetic steel sheets; A coil that generates a magnetic field in the gap and bends the trajectory of the charged particle beam passing through the gap into an arc having a center of curvature, wherein the electromagnet body is aligned with the arc-shaped trajectory through which the charged particle beam passes. The magnetic pole width in the deflection radial direction passing through the center of curvature of the track is shifted by one sheet at a time so that the central part of the track of the charged particle beam is larger than the entrance / exit side of the charged particle beam, and the electrode of each magnetic steel sheet. The effective magnetic field area of the electromagnet body is shifted by a certain dimension in the direction of the deflection radius passing through the center of curvature of the orbit with respect to the orbit of the charged particle beam. Deflection electromagnet adapted to shift to the orbit. 5. The bending electromagnet according to claim 1, wherein shims for increasing the magnetic flux density at both ends are provided at both ends of the magnetic poles in the deflection radial direction passing through the center of curvature of the orbit. 6. An electromagnet main body comprising a pair of magnetic poles facing each other via a gap and a yoke connecting the pair of magnetic poles, and formed by laminating a large number of electromagnetic steel plates, and provided on the electromagnet main body. A coil for bending a trajectory of a charged particle beam passing through the gap into an arc having a center of curvature by generating a uniform magnetic field in the gap, comprising: Forming a first stacked block and a second stacked block by cutting the block so as to have a cut surface perpendicular to a beam axis of the charged particle beam; and Joining the cut surface of the first laminated block and the cut surface of the second laminated block.