JPH0969431A - Stacked electromagnet - Google Patents

Abstract

(57) An object of the present invention is to secure a highly accurate magnetic pole surface of a laminated electromagnet, improve rigidity, and eliminate welding to manufacture at a low cost in a short time. SOLUTION: A plurality of cores 4 are stacked and housed in a frame 1 having a U-shaped cross section, an end plate 7 is attached to the left side of the frame 1 with bolts 6, and an end plate 7 is attached to a pin 9 to the right side of the frame 2.
Install by. At this time, a slight clearance is provided between the frame 1 and the right end plate 7. The plurality of cores 4 are pressed against the reference arc surface of the core 4 by applying a pressing plate 5 to the side surface and tightening with a bolt 6. Also, a plurality of cores 4
Is pressed against the upper surface of the core 4 and tightened with bolts so as to be pressed against the reference plane of the core 4. After that, the plurality of cores 4, the frame 1, and the both end plates 7 are fastened with tie rods 8.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a laminated electromagnet used in a synchrotron or the like.

[0002]

2. Description of the Related Art The structure of a conventional curved type laminated electromagnet will be described.

As shown in FIG. 8 (a), the structure of this laminated electromagnet is gradually displaced in the X direction with respect to the vertical axis Z of the laminated surface to secure a surface pressure of 10 to ²⁰ kg / cm ^2. While stacking a plurality of punching cores (iron cores) 21 and holding both ends with end plates 22 for holding the stacking pressure, the plurality of punching cores 21 and the two end plates 22 are formed on an arc. Side plate 2 with bend
It is structured such that it is welded and fixed to 3 and integrated. In addition, the four tie rods 24 are inserted into the plurality of punched cores 21 and the two end plates 22.

Japanese Patent Publication No. 3-78764 can be cited as a document describing this type of laminated electromagnet. However, the structure of this laminated electromagnet has the following drawbacks.

(1) The accuracy is inaccurate and the reproducibility during mass production is poor. Residual stress exists mainly due to welding heat input when stacking and fixing, and it was difficult to secure the flatness of the magnetic pole surface and the accuracy of the curved arc shape, and there were large variations among the individual products.

(2) The material cost of the punched core (iron core) is expensive. The iron core is composed of a silicon steel plate having a thickness of about 0.1 to 1 mm, but since the cores are originally arranged by using the side plates, the punched core 21 is formed as shown in FIG. The core has a notch 25, and the cost of the core is rising due to the cost increase due to the complicated shape of the mold for manufacturing the punched core. Furthermore, in order to minimize the heat input during welding and ensure the accuracy, as shown in FIGS.
1 and the side plate 23 may be lip-welded. (A)
Is a structure in which the concave side surface of the core 21 and the end side surface of the side plate 23 are lip-welded, and (b) is a structure in which the surface of the core 21 and the corner surface of the side plate 23 are lip-welded. In addition to the core cost, the side plate processing cost is high. Documents describing this type of technology include Japanese Utility Model Laid-Open No. 3-34211 and Japanese Patent Application Laid-Open No. 5-226146.
The gazette can be mentioned.

(3) There are many work steps for assembling and centering, which increases the work cost and requires skilled workers.

Usually, the following steps are taken until the completion of a welding type laminated electromagnet. It is formed with a curved die holding jig. Push in the Z direction with a hydraulic press. Tighten with a tie rod. Weld with an automatic welding machine. Perform distortion correction work. As described above, there are many work steps, and work such as, and, requires skill, work cost and work time due to the need for tools and devices such as a die jig, a hydraulic press and an automatic welding machine. It took a lot.

(4) The structure is not easy to maintain. Since the laminated electromagnet with this structure does not allow the punched core to splay after completion, the electromagnet complete set is remanufactured when there is a failure such as poor insulation or deformation of the iron core or when the shape of the iron core is changed. The structure is inflexible for modification and maintenance.

(5) The structure has low rigidity. In the welding type laminated electromagnet, as shown in FIG. 8, several separated side plates 23 and the punching core 21 are integrated by the welded fillet leg length, so the rigidity of the electromagnet as a whole is low. Therefore, there is a disadvantage that a large deformation that cannot withstand the electromagnetic force acting on the coil conductor is forcibly produced and the flatness of the magnetic pole surface and the accuracy of the curved arc shape are impaired.

FIG. 10 shows a curved laminated electromagnet having a fan-shaped iron core which is adopted when the bending amount is larger than that of the type shown in FIG. Although the cores 21 having different widths are combined or the spacers 26 are inserted between the cores 21 in order to secure the fan shape, the structure is more disadvantageous than the type of FIG. 8 in terms of accuracy and cost.

Documents describing this type of laminated electromagnet include Japanese Patent Laid-Open Nos. 5-258950 and 62-62.
No. 13006 can be mentioned.

As a document in which a laminated electromagnet having a U-shaped frame is described, Japanese Utility Model Publication No. 2-108300 can be cited.

[0014]

SUMMARY OF THE INVENTION In view of the above-mentioned conventional technique, the present invention is intended to solve the following problems in a laminated electromagnet.

(1) In order to stably travel a beam used in a synchrotron or the like, a curved and linear laminated electromagnet is realized while ensuring a necessary highly accurate magnetic pole surface.

(2) In particular, in order to cope with an electromagnet having a high magnetic field and a long stacking length, the rigidity that can withstand a large electromagnetic force generated in the coil conductor is ensured.

(3) To provide a laminated electromagnet which can be manufactured at low cost in a short time by simplifying the work of stacking and welding which requires high cost and long manufacturing time.

[0018]

The present invention employs the following means to solve the above-mentioned problems.

(1) A plurality of cores are housed in a frame having a U-shaped cross section, end plates are attached to both end faces of the frame, and the plurality of cores, the frame and the both end plates are screwed. Laminated electromagnet tightened with. (2) The laminated electromagnet according to (1), wherein the electromagnet has a curved shape. (3) The laminated electromagnet according to (1), wherein the electromagnet has a linear shape. (4) The laminated electromagnet according to (1), wherein the screw structure is a tie rod inserted through the plurality of cores and the both end plates. (5) The laminated electromagnet according to (1), wherein the screw structure is a reamer bolt provided between the frame and one of the both end plates. (6) The laminated electromagnet according to (1), wherein a cooling pipe is housed in a recess provided in the peripheral portion of the frame.

[0020]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described with reference to the drawings.

First, a first embodiment of the present invention will be described with reference to FIGS.
Shown in As shown in FIG. 1A, the assembly accuracy of the laminated magnet surface and the curved arc shape is the metal U-shape in which the reference plane 2 and the reference arc surface 3 for positioning with high precision are processed in advance. A plurality of cores 4 are secured to the frame 1 by tightening bolts 6 on the upper surface and the side surface of the holding plate 5 with the holding plate 5 interposed therebetween.

The stacking surface pressure in the Z-axis direction in FIG. 1 is adjusted by tightening the four tie rods 8 and adjusting the tightening force thereof, as shown in FIGS. 1 (b) and 2. To be done.

In FIG. 2, a pin 9 is provided between the frame 1 and the end plate 7. In the case of a laminated bending electromagnet having a thin core, by omitting the tie rod 8 and replacing the pin 9 with a reamer bolt, it is possible to tighten the cores 4 and prevent the frame 1 from opening. (Details will be described later).

The surface pressure of the laminated cores 4 in the laminating direction Z is usually 10 to 20 kg / cm ² depending on the tightening force of the tie rods 8 in order to secure a good space factor. .

In order to prevent the reaction force in the Z direction due to this tightening force from being transmitted to the frame 1, a clearance is provided between the frame 1 and the end plate 7.

Further, as shown in FIG. 4, the reaction force of the pressing plate 5 of the core 4 in the X and Y directions is generated in such a manner that the opening of the U-shaped frame 1 is opened in a broken line shape. This is an obstacle because the accuracy (flatness) of the contact surface with the core 4 of the frame 1 is impaired. Therefore, as shown in FIG. 2, a mechanism for providing the pin 9 between the frame 1 and the end plate 7 is adopted, and the rigidity of the end plate 7 prevents the frame 1 from being deformed.

FIG. 7 shows a linear laminated electromagnet according to the second embodiment of the present invention. In this type, the axial loads P of the straight tie rods 8 are equal to each other, and it is possible to expect an equal pressure of each core 4.

In the curved laminated electromagnet of the first embodiment of the present invention, it is not possible to expect an equal pressure in each core as in the linear laminated electromagnet of the second embodiment shown in FIG. . However, if the axial loads P _o and P _i in FIG. 2 are adjusted so that the overall balance of the moment effect due to the superposition of the internal pressures of all the cores can be balanced, there is no problem.

The core does not require any work for welding and fixing,
Since it suffices to provide only the long holes through which the tie rods are inserted, the core has a simple shape and the cost is low.

Since the laminated electromagnet has a structure in which all the cores are housed in a U-shaped frame, the rigidity thereof is remarkably increased, and the electromagnetic force of the coil generated in the electromagnet, the self-weight deflection, and the transportation electromagnet are generated. Can withstand the impact of.

Further, considering that the contact pressure and the contact area between the core and the frame can be sufficiently secured, as shown in FIG. 5, heat generated by iron loss in the core 4 and the coil conductor 10 during high frequency excitation are generated. In order to remove the Joule heat that is generated, it is possible to adopt an effective heat removal measure such as providing the cooling pipe 12 along the recess 13 of the frame 1. In addition,
The two coil conductors 10 are held by the joint material 11.

In other words, in the present invention, since the core is not restrained by welding, it is possible to easily deal with the need to replace the core itself.

However, the present invention is not applicable to all curved laminated electromagnets. As shown in FIG. 6A, when the degree of curvature of the arc (the maximum value of the distance between the arc and the chord) b is smaller than the width a of the core (b <a), the curved shape has the intended purpose. Can be achieved, but as shown in FIG.
With the curved shape in the case of> a, it is no longer possible to arrange the tie rods so that the compressive force is evenly distributed to all the cores laminated in the frame.

In view of the features of the technique, the present invention is a combined (divided) type (actual open flat type) in which the laminated core of the upper half body group (iron core) and the laminated core of the lower half body group are fastened with bolts. 3-
(See Japanese Patent No. 86600), the entire electromagnet is a group of 1
It can also be applied to a sheet-type electromagnet.

[0035]

As is apparent from the above description, the present invention can be used in a particle accelerator or the like and has the following effects.

(1) Since the laminated electromagnet for deflecting (converging in some cases) the beam has high magnetic pole face accuracy,
It contributes to the stability of the beam orbit, which in turn helps improve the strength of the extracted beam.

(2) Since the welding technique for reducing strain, which is difficult and requires skill, is abolished, the cost can be reduced and an inexpensive laminated electromagnet can be manufactured in a short time.

(3) The rigidity required for the electromagnet can be improved, and a cooling structure for dealing with heat generation can be provided.

[Brief description of drawings]

1A and 1B are perspective views of a main part according to a first embodiment of the present invention, in which FIG. 1A is a sectional view and FIG. 1B is a perspective view.

FIG. 2 is a cross-sectional view of the first embodiment of the present invention.

3A and 3B are side views of FIG. 2, in which FIG. 3A is a view seen in an α direction, and FIG. 3B is a view seen in a β direction.

FIG. 4 is a cross-sectional view for explaining a state of deformation occurring in the frame according to the first embodiment of the present invention.

5A and 5B show a case where a cooling structure is provided in the first embodiment of the present invention, FIG. 5A is a sectional view, and FIG. 5B is a perspective view of a part of FIG.

6A and 6B are views for explaining what kind of curved laminated electromagnet the present invention can be applied to, where FIG. 6A is an applicable diagram and FIG. 6B is an unapplicable diagram. .

FIG. 7 is a sectional view of a second embodiment of the present invention.

8A and 8B show a conventional curved laminated electromagnet, in which FIG. 8A is a perspective view and FIG. 8B is a view of FIG. 8A in the α direction.

9A and 9B are plan views of a conventional curved laminated electromagnet when lip welding is performed, in which FIG. 9A shows a first lip welding structure and FIG. 9B shows a second lip welding structure.

FIG. 10 is a perspective view of another conventional curved laminated electromagnet.

[Explanation of symbols]

 1 Frame 2 Reference plane 3 Reference arc surface 4 Core 5 Holding plate 6 Bolt 7 End plate 8 Tie rod 9 Pin 10 Coil conductor 11 Joint material 12 Cooling pipe 13 Recess

Claims (6)

[Claims] 1. A plurality of cores are housed in a frame having a U-shaped cross section, end plates are attached to both end faces of the frame, and the plurality of cores, the frame, and the both end plates have a screw structure. A laminated electromagnet characterized by being tightened. 2. The laminated electromagnet according to claim 1, wherein the electromagnet has a curved shape. 3. The laminated electromagnet according to claim 1, wherein the electromagnet has a linear shape. 4. The laminated electromagnet according to claim 1, wherein the screw structure is a tie rod inserted through the plurality of cores and the end plates. 5. The laminated electromagnet according to claim 1, wherein the screw structure is a reamer bolt provided between the frame and one of the both end plates. 6. The laminated electromagnet according to claim 1, wherein a cooling pipe is housed in a recess provided in the peripheral portion of the frame.