JPH10270764A - Superconducting switch and manufacturing method thereof - Google Patents

Abstract

PROBLEM TO BE SOLVED: To simplify a manufacture by providing a superconducting winding wire, in which a superconducting multi-core wire formed by intertwining a plurality of superconducting wires is wound around a bobbin and an end of each superconducting wire is electrically connected to an end of another superconducting wire, and a transition means which transfers the superconducting winding wire between a superconducting condition and a normal conducting condition. SOLUTION: A plurality of superconducting wires 4 are spirally intertwined to form a superconducting multi-core wire 1. After one superconducting multi-core wire 1 is wound around a bobbin 2, the end of winding end of an arbitrary superconducting wire 4 is connected to the end of winding beginning of the next superconducting wire 4, and one superconducting wire winding wire 20 is formed in all by sequentially repeating this manner. By immersing in a cooling medium of a boiling point equal to a transition temperature of the superconducting wire 4 or below, to form a superconducting switch. Relating to opening/closing of the switch, by applying a current to a heater 5, the superconducting wire 4 is made in a normal conducting condition, and by shutting off the current, it is made in a superconducting condition. Because the superconducting multi-core wire 1 formed by intertwining a plurality of superconducting wires 4 is wound around the bobbin 2, the number of times of winding is decreased, and manufacture is simplified.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a superconducting switch using superconducting and superconducting transitions of a superconductor and used in parallel with a superconducting coil.

[0002]

2. Description of the Related Art The superconducting state is a thermodynamic phase in which the ambient temperature or the magnetic field has a certain value T, respectively.
A superconducting state is realized below c and Hc. In the superconducting state, the electric resistance disappears, and in the normal conducting state, it has a finite value. Therefore, by changing the temperature of the superconductor and the magnetic field applied to the superconductor, the transition between the superconducting state with zero electric resistance and the normal conducting state with electric resistance finite can be controlled, and this property was used for the switch. What is a superconducting switch. In particular, when a superconducting coil is subjected to permanent current excitation, this type of switch is often used.

FIG. 8 is a cross-sectional view showing a conventional superconducting switch disclosed in, for example, Japanese Patent Publication No. 51-47599. In the figure, one continuous superconducting wire 6 is wound around a winding frame 7 made of a heat insulator such as plastics. Further, at both ends thereof, terminals of a switch (not shown) are formed. A heating element 8 is provided between the wound superconducting wire 6 and the winding frame 7. Heating element 8
Is connected to a lead wire (not shown). Then, metal layer 10 is wound around bobbin 7 together with superconducting wire 6 so as to sandwich superconducting wire 6. Further, an insulating layer 11 is provided between the superconducting wire 6 and the metal layer 10 to insulate the superconducting wire 6 from each other and to maintain a good thermal conduction state. The outer periphery of the wound superconducting wire 6 is covered with a heat insulating layer 9.

The thus formed assembly is immersed in a cooling medium having a boiling point equal to or lower than the transition temperature Tc of the superconducting wire 6, such as liquid helium, to form a superconducting switch. The opening and closing of the superconducting switch is performed by turning the superconducting wire 6 into the normal conducting state by supplying a current to the heating element 8 and by turning off the heating element 8 to bring the superconducting state into the superconducting state. The means for bringing the superconducting wire 6 into the normal conducting state does not necessarily need to be provided by the heating element 8; the cooling medium is temporarily removed from around the switch or the switch itself is moved to a space where the cooling medium does not exist. Is also good. Alternatively, a magnetic field of Hc or more may be applied to superconducting wire 6 by an appropriate magnet coil.

[0005] The conventional superconducting switch thus configured is used by connecting both ends of a superconducting wire 6 in parallel to a superconducting coil (not shown). When the superconducting wire 6 of the superconducting switch is heated by the heating element 8 to a temperature higher than the critical temperature, resistance is generated. Next, the superconducting coil is excited by a DC power supply connected in parallel with the superconducting coil. Next, the temperature of superconducting wire 6 is reduced to a temperature below the critical temperature, and the superconducting switch is brought into a superconducting state. Thereafter, when the current of the DC power supply is reduced to zero, a circuit of permanent current is created by the superconducting coil and the superconducting switch.

[0006]

Generally, a superconducting switch is used as described above, and needs to have a predetermined resistance in a normal conducting state at a critical temperature or higher. In order to obtain this predetermined resistance, for example, a long superconducting wire 6 is
Must be wound. However, long superconducting wires 6
It is not easy to wind the superconducting wire 6 around the winding frame 7 uniformly and neatly, and the winding of the long superconducting wire 6 many times around the winding frame 7 is not excellent in stability of the superconducting wire 6.

SUMMARY OF THE INVENTION The present invention has been made to solve the above problems, and provides a superconducting switch which is easy to manufacture, has excellent stability, and is easy to use, and a method for manufacturing the same. It is intended for.

[0008]

In the superconducting switch according to the first aspect, a superconducting multi-core wire formed by twisting a plurality of superconducting wires is wound around a bobbin, and the end of each superconducting wire is connected to another superconducting wire. It has a superconducting winding electrically connected to the end of the wire, and transition means for transitioning the superconducting winding between a superconducting state and a normal conducting state.

In the superconducting switch of the second aspect, the plurality of superconducting wires are connected such that the direction of the current flowing through each superconducting wire is the same as the rotating direction with respect to the bobbin.

In the superconducting switch according to a third aspect, the plurality of superconducting wires are connected such that the direction of the current flowing through each superconducting wire is alternately folded with respect to the winding direction of the bobbin.

In the superconducting switch according to a fourth aspect, a plurality of superconducting wires are electrically connected in parallel to form a bundle, and the direction of the current flowing through the bundle is the same with respect to the bobbin. They are connected in the direction of rotation.

In the superconducting switch according to the fifth aspect, a predetermined number of the superconducting wires are electrically connected in parallel to form a bundle, and the direction of the current flowing through the bundle is in the winding direction of the bobbin. They are connected so that they are turned back alternately.

According to a sixth aspect of the present invention, there is provided a method for manufacturing a superconducting switch, wherein a superconducting multi-core wire formed by twisting a plurality of superconducting wires is wound around a bobbin, Electrically connecting to the end of the wire.

[0014]

BEST MODE FOR CARRYING OUT THE INVENTION

Embodiment 1 FIG. FIG. 1 is a sectional view showing a superconducting switch of the present invention. FIG. 2 is a perspective view of the superconducting multi-core wire. FIG. 3 is a sectional view of a superconducting wire. FIG. 4 is an explanatory view showing how the superconducting wires are connected. In FIG. 1, one long superconducting multi-core wire 1 having a predetermined length is
Reel 2 made of a thermal insulator such as plastics
Are wound a plurality of times to form a superconducting winding 20.
Between the wound superconducting multi-core wire 1 and the winding frame 2, a heater 5 as a heating element is disposed. A lead wire (not shown) is connected to the heater 5. Further, the outer periphery of the wound superconducting multi-core wire 1 is covered with a heat insulating layer 3.

In FIG. 2, a superconducting wire 4 coated with insulation is shown.
Are combined in a spiral form to form one superconducting multifilamentary wire 1. As shown in FIG. 3, one superconducting wire 4 is manufactured by covering a composite wire 4 b in which a superconducting element wire is embedded in a high-resistance metal with an insulating coating 4 a.

FIG. 4 shows how the respective superconducting wires 4 are connected. After one superconducting multi-core wire 1 is wound around the bobbin 2,
As shown in FIG. 4, the superconducting wires 4 constituting the superconducting multifilamentary wire 1 are electrically connected so that the direction of the current I flowing through each superconducting wire 4 is the same as the rotation direction with respect to the bobbin 2. Connected. That is, the winding end of an arbitrary superconducting wire 4 is connected to the winding start end of the next superconducting wire 4, and this is sequentially repeated to form one superconducting wire as a whole, and the superconducting winding 20 is formed. I have. The winding start end of the first superconducting wire 4 and the winding end end of the last superconducting wire 4 are connected to external electric wires as terminals. One connected superconducting wire is configured so as to obtain a predetermined resistance as a whole.

The assembly thus formed is immersed in a cooling medium (for example, liquid helium) having a boiling point lower than the transition temperature Tc of the superconducting wire 4 to form a superconducting switch. The opening and closing of the superconducting switch is performed by supplying a current to the heater 5 to bring the superconducting wire 4 into a normal conducting state, and by turning off the heater 5 to bring it into the superconducting state. The heater 5 and the cooling medium (not shown) are transition means for transitioning the superconducting winding 20 between a superconducting state and a normal conducting state.

The superconducting switch thus configured is
The both ends of the superconducting winding 20 are used in parallel with a superconducting coil (not shown). When the superconducting winding 20 of the superconducting switch is heated by the heating element 8 to a temperature higher than the critical temperature, a resistance is generated. Next, the superconducting coil is excited by a DC power supply connected in parallel with the superconducting coil. Next, the temperature of the superconducting winding 20 is reduced to a critical temperature or lower, and the superconducting switch is brought into a superconducting state. Thereafter, when the current of the DC power supply is reduced to zero, a circuit of permanent current is created by the superconducting coil and the superconducting switch.

In the superconducting switch having such a configuration, the superconducting multifilamentary wire 1 formed by joining a plurality of superconducting wires 4 is wound around the bobbin 2, so that the number of windings is reduced and the fabrication is easy. is there. Further, since the superconducting wire 4 twisted in advance is used, it can be wound uniformly and neatly, and a superconducting switch having excellent stability can be obtained.

As a transition means for transitioning the superconducting winding 20 between the superconducting state and the normal conducting state, the heater 5 does not necessarily need to be used, and the cooling medium may be temporarily removed from around the switch. Alternatively, the switch itself may be moved to a space where no cooling medium exists, and furthermore, Hc may be connected to the superconducting wire 4 by an appropriate magnet coil.
The above-described magnetic field may be applied, and it goes without saying that in such a configuration, the heat insulating layer 3 becomes unnecessary.

Embodiment 2 FIG. FIG. 5 is an explanatory view showing how to connect superconducting wires showing another example of the superconducting switch of the present invention. In the present embodiment, after the superconducting multifilamentary wire 1 is wound around the bobbin 2, the plurality of superconducting wires 4 constituting the superconducting multifilamentary wire 1 are, as shown in FIG. The direction of the current I flowing through the winding frame 2 is alternately turned back with respect to the winding direction of the winding frame 2. That is,
In one superconducting multifilamentary wire 1, the winding end of any superconducting wire 4 is connected to the winding end of the next superconducting wire 4, and the winding beginning of that superconducting wire 4 is further connected to the next superconducting wire 4. It is connected to the winding start end. This is sequentially repeated to form one superconducting wire as a whole. And
The winding start end of the first superconducting wire 4 and the last superconducting wire 4
Is connected to an external electric wire as a terminal. One connected superconducting wire is configured so as to obtain a predetermined resistance as a whole. Other configurations are the same as those of the first embodiment.

In the superconducting switch having such a configuration, the current I flowing through each superconducting wire 4 flows alternately in the winding direction of the bobbin 2. for that reason,
The magnetic field generated by the superconducting wire 4 is canceled by adjacent ones. Therefore, when the superconducting coil is excited, the electromagnetic force of the superconducting coil does not act on the superconducting switch. Further, since no magnetic field is generated, other devices are not affected.

Embodiment 3 FIG. FIG. 6 is an explanatory view showing how to connect superconducting wires showing another example of the superconducting switch of the present invention. In the present embodiment, after the superconducting multi-core wire 1 is wound around the bobbin 2, as shown in FIG. Of superconducting wires 4 are connected at the winding start end and the winding end end and are electrically connected in parallel, and a plurality of electrically parallel bundles are produced. It is connected so that the direction of the flowing current I is in the same rotation direction with respect to the bobbin 2. The connection portion at the winding start end of the first bundle and the connection portion at the winding end end of the last bundle are connected to external electric wires as terminals. One connected superconducting wire is configured so as to obtain a predetermined resistance as a whole. In the example of FIG. 6, the number of the superconducting wires 4 electrically connected in parallel is two, but the number is not limited to two, and the number is appropriately increased in accordance with the superconducting coil and the power supply to be used. Other configurations are the same as those of the first embodiment.

In the superconducting switch having such a configuration, a superconducting multifilamentary wire 1 formed by combining a plurality of superconducting wires 4 is wound around a bobbin 2, and a predetermined number of superconducting coils and a power source are provided. Since they are connected in parallel, a superconducting switch having a predetermined resistance value and current value can be easily manufactured. In addition, by appropriately changing the number of connected devices, a predetermined resistance value and a predetermined current value can be obtained, and a superconducting switch having various characteristics can be obtained without major design changes.

Embodiment 4 FIG. 7 is an explanatory view showing how to connect superconducting wires showing another example of the superconducting switch of the present invention. In the present embodiment, after the superconducting multifilamentary wire 1 is wound around the bobbin 2, a plurality of superconducting wires 4 constituting the superconducting multifilamentary wire 1 are, as shown in FIG. Of superconducting wires 4 are connected at the winding start end and the winding end end and are electrically connected in parallel, and a plurality of electrically parallel bundles are produced. The connection is made such that the direction of the flowing current is alternately turned back with respect to the winding direction of the bobbin. The connection portion at the winding start end of the first bundle and the connection portion at the winding end end of the last bundle are connected to external electric wires as terminals. One connected superconducting wire is configured so as to obtain a predetermined resistance as a whole. In the example of FIG. 7, the number of the superconducting wires 4 electrically connected in parallel is two, but the number is not limited to two, and the number is appropriately increased in accordance with the superconducting coil and the power supply to be used. Other configurations are the same as those of the third embodiment.

In the superconducting switch having such a configuration, a plurality of superconducting wires 4 are connected in parallel corresponding to the superconducting coil and the power supply to be connected, and a superconducting switch having a predetermined resistance value and current value can be easily manufactured. Produced. The current I flowing through the bundle of superconducting wires 4 connected in parallel is
Flows alternately in the winding direction of the winding frame 2. Therefore, the magnetic field generated by the superconducting wire 4 is canceled by adjacent ones. Therefore, when the superconducting coil is excited, the electromagnetic force of the superconducting coil does not act on the superconducting switch. Further, since no magnetic field is generated, other devices are not affected.

[0027]

According to the superconducting switch of the first aspect,
A superconducting multi-core wire formed by twisting a plurality of superconducting wires is wound around a bobbin, and an end of each superconducting wire is electrically connected to an end of another superconducting wire; and a superconducting winding. Transition means for transitioning the wire between the superconducting state and the normal conducting state. For this reason, since a superconducting wire twisted in advance is used, the number of windings is reduced and fabrication is easy. Further, a plurality of superconducting wires can be wound uniformly and orderly, and a superconducting switch having excellent stability can be obtained.

In the superconducting switch according to the second aspect, the plurality of superconducting wires are connected such that the direction of the current flowing through each superconducting wire is the same as the rotation direction with respect to the bobbin. Therefore, a superconducting switch having a predetermined resistance can be easily manufactured.

In the superconducting switch according to the third aspect, the plurality of superconducting wires are connected such that the direction of the current flowing through each superconducting wire is alternately folded with respect to the winding direction of the bobbin. For this reason, the magnetic field generated by the superconducting wire is canceled by adjacent ones. As a result, when the connected superconducting coil is excited, the electromagnetic force of the superconducting coil does not act on the superconducting switch. Further, since no magnetic field is generated, other devices are not affected.

In the superconducting switch according to the fourth aspect, the plurality of superconducting wires are electrically connected in parallel to form a bundle, and the direction of the current flowing through the bundle is the same with respect to the bobbin. They are connected in the direction of rotation. for that reason,
A superconducting switch having a predetermined resistance value and current value can be easily manufactured.

In the superconducting switch according to the fifth aspect, a predetermined number of the superconducting wires are electrically connected in parallel to form a bundle, and the direction of the current flowing through the bundle is in the winding direction of the bobbin. They are connected so that they are turned back alternately. Therefore, a superconducting switch having a predetermined resistance value and current value can be easily manufactured. Then, the magnetic field generated by the superconducting wire is canceled out by adjacent ones.
As a result, when the connected superconducting coil is excited, the electromagnetic force of the superconducting coil does not act on the superconducting switch. Further, since no magnetic field is generated, other devices are not affected.

In the method of manufacturing a superconducting switch according to a sixth aspect, a superconducting multifilamentary wire formed by twisting a plurality of superconducting wires is wound around a bobbin, and an end of each superconducting wire is connected to another superconducting wire. Electrically connecting to the end of the wire. Therefore, since a superconducting wire twisted in advance is used, the number of windings is reduced, and the fabrication is easy. Further, a plurality of superconducting wires can be wound uniformly and orderly, and a superconducting switch having excellent stability can be obtained.

[Brief description of the drawings]

FIG. 1 is a sectional view showing a superconducting switch of the present invention.

FIG. 2 is a perspective view of a superconducting multi-core wire.

FIG. 3 is a cross-sectional view of a superconducting wire.

FIG. 4 is an explanatory diagram showing how a superconducting wire is connected.

FIG. 5 is an explanatory view showing how to connect superconducting wires showing another example of the superconducting switch of the present invention.

FIG. 6 is an explanatory view showing how to connect superconducting wires showing another example of the superconducting switch of the present invention.

FIG. 7 is an explanatory view showing how to connect superconducting wires showing another example of the superconducting switch of the present invention.

FIG. 8 is a sectional view showing a conventional superconducting switch.

[Explanation of symbols]

1 superconducting multi-core wire, 2 winding frames, 4 superconducting wires, 5 heaters (transition means), 20 superconducting windings.

Claims (6)

[Claims] 1. A superconducting multifilamentary wire formed by twisting a plurality of superconducting wires is wound around a bobbin, and an end of each superconducting wire is electrically connected to an end of the other superconducting wire. A superconducting switch comprising: a superconducting winding; and a transition unit that transitions the superconducting winding between a superconducting state and a normal conducting state. 2. The plurality of superconducting wires are connected such that the direction of current flowing through each superconducting wire is the same as the rotation direction with respect to the bobbin. The superconducting switch as described. 3. The plurality of superconducting wires are connected such that a direction of a current flowing through each superconducting wire is alternately folded with respect to a winding direction of the bobbin. 2. The superconducting switch according to 1. 4. A plurality of said superconducting wires are electrically connected in parallel to form a bundle, and a direction of a current flowing through said bundle is the same direction of rotation with respect to said bobbin. 2. The superconducting switch according to claim 1, wherein the superconducting switch is connected in such a manner as to be described above. 5. A plurality of said superconducting wires are electrically connected in parallel to form a bundle, and a direction of a current flowing through said bundle is alternately set with respect to a winding direction of said bobbin. 2. The superconducting switch according to claim 1, wherein the switch is connected so as to be folded back. 6. A step of winding a superconducting multifilamentary wire formed by twisting a plurality of superconducting wires around a bobbin, and electrically connecting one end of each superconducting wire to an end of the other superconducting wire. And a method of manufacturing a superconducting switch.