JPS61171082A - Heater wire for heating superconductor and manufacture thereof - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Field of Application] The present invention relates to a heater wire for a superconductor and a method for manufacturing the same.

[Prior art] The four superconductors exhibit superconductivity only at low temperatures.

In order to evaluate how stable a superconducting magnet using four superconducting bodies is without quenching, it is often necessary to partially heat the four superconducting bodies inside the magnet and measure the amount of heating required to partially make it normal conductive. be. Furthermore, the switching function in a superconducting switch utilizes normal conductivity caused by heating.

In these, an electric heater is usually used as the heating means. A small current is applied to the heater to generate heat and heat the four superconductors.

As a heater, an electric heating wire wrapped with resin (eg, polyester, Teflon, etc.) tape is sometimes used. However, since the heater is placed along the conductor, bending when making the conductor into a coil,
There is a high possibility that the heater tape will tear due to compression, resulting in dielectric breakdown.

If the tape tears, the conductor must be rewound to replace the insulated heater, damaging the conductor. If the conductor containing the heater is entangled, it is impossible to replace the heater. Furthermore, since the insulating layer of the tape is thick and has poor thermal conductivity, heat generated by the heater is difficult to conduct to the superconducting wires, resulting in poor responsiveness.

[Object of the Invention] An object of the present invention is to provide a heater for a superconductor that does not cause dielectric breakdown.

[Structure of the Invention] The gist of the present invention resides in an electric heating wire, a heater wire for heating a superconductor comprising an insulating fiber impregnated with a curable resin, and a method for manufacturing the same.

The method of the invention consists of wrapping insulating fibers around an electrically heating wire to cover the surface of the electrically heating wire, and then impregnating the insulating fibers with a curable resin.

The heating wire is a conventional heating wire, and examples include a nickel wire and a nichrome wire. The heating wire may be enamelled beforehand and may be, for example, Cypronic wire.

Curable resins are insulating resins that do not flow even when heated by a heater, such as phenolic resins, furan resins, yurya resins, melamine resins, alkyd resins, unsaturated polyester resins, epoxy resins, and cyanoacrylate resins. Illustrated.

Insulating fibers may be either inorganic or organic;
For example, glass fibers, polyamide (e.g. nylon and aromatic polyamide) fibers, polyether (e.g.
Examples include (polyacecool) fibers. The insulating fiber has heat resistance against heat generated by the heating wire. The insulating fiber can be wound around the heating wire as a filament, but it is preferable to wind it around the heating wire as a twisted thread. Insulating fiber roll
Various conventional winding methods may be used for the J-wrapping method, but horizontal winding is preferred.

FIG. 1 is a perspective view showing a heater wire of the present invention. The heater wire 1 consists of a heating wire 2, an insulating fiber thread 3 covering the heating wire 2, and a curable resin. Insulating fiber yarn is
Although shown in a horizontally wound state, it may be wound in any manner.

FIG. 2 is a perspective view showing four superconducting bodies. The superconductor 4 body 1O consists of a heater wire 11, a superconductor wire 4, and a stabilized copper 5 that accommodates them.

[Effects of the Invention] The heater wire of the present invention has many advantages. Because the composite strength of the resin-impregnated insulating fibers is high (the mechanical strength of the insulator is high), the heater insulation will not rupture even when the conductor is bent (for example, into a coil). Since the coating thickness can be made thin by adjusting the diameter and number of turns of the insulating fiber, the thermal response to the superconducting wire is good.

In particular, since the heater wire can be embedded in the conductor, a compact thermal superconducting switch with fast switching speed and good response can be manufactured.

The heater wire of the present invention is particularly useful in superconducting magnet conductors, superconducting switches, etc. [Examples] Examples are shown below.

Example Formal coated heating wire (outer diameter 0.7 mm)
Then, 19 glass fiber threads (outer diameter 70 μm) were wound in a helical shape, and a horizontal wrapping was applied (see Fig. 1). Next, the glass fiber yarn was impregnated with Aron Alpha (cyanoacrylate resin, manufactured by Toagosei Chemical Co., Ltd.). This heater wire was embedded in four superconducting bodies (width 5111, height 2 inches) (see Figure 2). As shown in Figure 3, the cylinder it (outer diameter 50mm
), four superconducting bodies 10 were wound into a six-turn coil. Five of these samples were manufactured and mega-checked at 1ooov for 3 minutes. The resistances of the five samples are all ■,
It was confirmed that the electrical insulation was good.

[Brief explanation of drawings]

FIG. 1 is a perspective view showing a heater wire of the present invention, FIG. 2 is a perspective view showing four superconductors, and FIG. 3 is a perspective view showing a sample wound with four superconductors. l... Heater wire, 2... Heat generating wire, 3... Insulating fiber thread, 4... Superconducting wire, 5... Stabilized copper, l
O...Superconductor, 11...Cylinder. Patent Applicant Sumitomo Electric Industries Co., Ltd. Representative Patent Attorney Aobai Ao and 2 others No. 11! 1 Column 2a! ! 13m

Claims (4)

[Claims] (1) A heater wire for heating a superconductor comprising an electric heating wire and an insulating fiber impregnated with a curable resin. (2) A heater wire for heating a superconductor according to claim 1, which has an enamel coating on the electric heating wire. (3) A method for manufacturing a heater wire for heating a superconductor, which comprises wrapping an insulating fiber around an electric heating wire to cover the surface of the electric heating wire, and then impregnating the insulating fiber with a curable resin. (4) The manufacturing method according to claim 3, wherein the electric heating wire is coated with enamel in advance.