JPS60244012A - Manufacture of electromagnetic coil - Google Patents

Abstract

PURPOSE:To manufacture at the same time electromagnetic coils of the several number of pieces to generate no exfoliation between turns by a method wherein a flat board is equipped to the opened side of a coil form to press the side of a bundle of strands, and the outside periphery of the bundle of the strands is pressed according to press tools equipped to the outside peripheries of the coil form and the flat board. CONSTITUTION:A coil form 3 is enabled to be wound at the same time with the several number or pieces of double pancake coils for formation of a coil of one piece, and the pancake coils 8a, 8b, 8c, 8d are wound thereon. Dummy conductors 12 are wound by one turn around the winding end parts of the individual pancake coils. Then after the whole pancake coils are wound around, a clamp 4 is fixed according to fixing bolts 5 arranged at the equal interval on the circumference of the coil form 3, and a patch 6 arranged on the outside diametrical circumference of the pancake coils is clamped according to clamp bolts 7. When the whole of the coil is put in a drying chamber and heated, adhesive varnish of turn insulation 2 wound round on hollow conductors 1 is hardened, and between the respective turns and between the respective pancake coils are adhered to be formed in one body. According to this manufacturing method, because the dummy conductors are wound around the winding end sides of the coils, between the turns are adhered sufficiently, and exfoliation is not generated between the turns.

Description

DETAILED DESCRIPTION OF THE INVENTION [Technical Field of the Invention] The present invention relates to a method for manufacturing an annular electromagnetic coil used in nuclear fusion devices and the like.

[Technical background of the invention and its problems]

A tokamak-shaped fusion device is equipped with an annular toroidal coil or boroidal. FIG. 2 shows a cross section of a toroidal coil or a poloidal coil, which is made up of 24 turns of a water-cooled hollow conductor 1 and has six layers in the radial direction of the coil. There are two types of coil winding methods: solenoid winding, which is normally wound continuously, and double pancake winding, where two layers of coils are layered into one double pancake. When winding a double pancake circular coil, conventionally a hollow conductor 1 is used as shown in Figures 3 and 4.
Turn insulation 2 is applied on the hollow conductor 1, and tension is applied to the hollow conductor 1 from the inner diameter side to the outer diameter side by a tension device (not shown), and then the winding form 3 is attached to a winding machine (not shown).
Rotate and wrap in sequence. Subsequently, one double pancake is formed by wrapping layer B in the same manner. In order to prevent the pancake coil wound in this way from deforming and keep the dimensions to the designed values, clamps 4 are fixed with mounting bolts 5 evenly distributed on the circumference of the winding form 3. After tightening the pads 6 arranged on the outer circumference with bolts 7, the whole is heated and molded in a drying room.

Stack several heat-molded pancake coils (for example, as shown in Figure 2VC, combine four pancake coils 8a, 8b, 8c, and 8d. Interlayer insulation 9 is inserted between the pancakes) to form one coil. After that, apply ground insulation 10.

In this conventional coil winding method, several winding molds are required to wrap and heat mold each pancake one by one, and additionally, heating molding is performed even after stacking several pancakes, which requires a separate coil winding method. A winding form must be manufactured. Furthermore, when heating molding is performed with the outer diameter of the pancake coil tightened using clamps equally distributed on the circumference, the clamp positions are sufficiently tightened as shown in Figure 5, but the space between the clamps bulges toward the outer diameter. 11 occurs, and the turns are not bonded enough and the turns become separated.In fusion devices, the electromagnetic force is usually large, so the mechanical stress is close to the allowable limit, so the VC between the conductors is 300V or more, and depending on the coil, the voltage is 3KV. or more voltage is generated.

The conductors are therefore subjected to severe electrical and mechanical loads.

This inter-turn separation not only weakens the electrical and mechanical strength but also creates an error magnetic field with respect to the plasma, which is unfavorable for maintaining plasma stability. The disadvantage is that it takes many days to produce a small coil and the manufacturing cost is high.

[Purpose of the invention]

The present invention has been made to eliminate the above-mentioned drawbacks, and an object of the present invention is to provide a method for manufacturing several electromagnetic coils at once without peeling between turns.

[Summary of the invention]

In order to achieve the above object, in the method for manufacturing an electromagnetic coil of the present invention, a wire is wound around an annular winding former having a rectangular cross-section to form a wire bundle having a dummy winding on the outermost periphery. Attach a flat plate to the open side surface and press the side part of the wire bundle 1. Press the outer circumferential surface of the wire bundle with a suppressor attached to the winding form and the outer periphery of the flat plate to solidify the wires together. [Embodiment of the Invention] An embodiment of the present invention will be described below with reference to FIG. 1.

The winding form 3 is one that can be used to wind several double pancakes forming one coil at once.
- Wrap around f 8a, 8b, 8c, and 8d. A dummy conductor 12 is wrapped around the end of each pancake. Next, after wrapping all the pancakes, attach the clamp 4 to the winding form 3.
It is fixed with mounting bolts 5 equally spaced on the circumference of the pancake coil, and bolts 7 are used to tighten the metal fittings 6 arranged on the outer circumference of the pancake coil.

This process will be explained in more detail as follows. A turn insulation 2 containing an adhesive face is applied on the hollow conductor 1, and the layer A is first attached to a winding machine (not shown) while applying tension to the hollow conductor 1 from the inner diameter side to the outer diameter side using a tension device (not shown). The winding form 3 is rotated and wound in sequence. The hollow conductor 1 or another conductor having a width dimension that is almost the same as the hollow conductor 10 is wound around the end of the winding side as a dummy conductor 12 while applying tension to the end of the winding with a tension device, and the clamp 4 is used to tighten the dummy conductor with the mounting bolt 5. Fix the conductor 12. A release tape (for example, Teflon tape) is wound on the dummy conductor 12 so that it does not adhere to the turn insulation 2 wound on the hollow conductor 1. In the same way, after winding pancakes 8a, 8b, 8c, and 8d in sequence, flange 3 is fixed with tightening bolts 14. The winding form 3 and the flange 13 are held concentrically by the spigot 15, and the outer diameter side of the coil is fixed by a stud 17 passed through a circular tubular spacer 16.

The spacer 16 is attached to maintain the winding width of the coil at the designed dimension, and by tightening the tightening nut 18 of the stud 17, the winding width of the coil is maintained at the designed dimension. When the entire coil tightened in steps 1 to 1 is placed in a drying room and heated at a specified temperature for a specified period of time, the adhesive face of the turn insulation 2 wound on the hollow conductor 1 will harden, and the adhesive face between each turn and each pan will harden. An integrated coil is obtained by bonding the cakes together. By winding the dummy conductor 12 in this way, the coil manufactured by K has no bulge between the clamps unlike a conventional coil, and the turns are sufficiently bonded. Since there is no stacking of pancakes after heating and molding them, the center of each pancake is the same, and the magnetic field precision is high, making Ciplasma much more stable than before.

Although the above explanation has been made based on a double pancake-shaped coil, this manufacturing method can be applied to all annular electromagnetic coils.

〔Effect of the invention〕

As explained above, according to the present invention, since the dummy conductor is wound around the end 9 side of the coil, the turns are sufficiently bonded and there is no peeling between the turns, resulting in high mechanical strength and low reliability. An electromagnetic coil is obtained. Furthermore, since several coils are heated and molded at once, the center of each coil is the same, increasing the precision of the generated magnetic field.

[Brief explanation of the drawing]

FIG. 1 is a sectional view showing an example of the method for manufacturing an electromagnetic coil according to the present invention, FIG. 2 is a sectional view of an example of an electromagnetic coil common to the prior art and the present invention, and FIG. Show l
li side view, Figure 4 is a side view seen from the ■ arrow direction in Figure 3,
FIG. 5 is a side view of an electromagnetic coil produced by a conventional method. DESCRIPTION OF SYMBOLS 1... Hollow conductor, 2... Turn insulation, 3... Winding form, 6... Batch, 12... Dummy conductor, 13... Flange. Agent: Patent Attorney Noriyuki Chika (and 1 other person) Figure 1 Figure 2 Figure 3 Figure 4 Figure 5

Claims (1)

[Claims] Wrapping the strands around an annular winding former with a cross-sectional shape to form a strand bundle having a dummy winding on the outermost periphery, attaching a flat plate to the open side of the winding former and pressing the side of the strand bundle, A method for manufacturing an electromagnetic coil, characterized in that the outer peripheral surface of the wire bundle is pressed by a suppressor attached to the outer periphery of the winding former and the flat plate to solidify the wires together.