JPH01157021A - Superconducting thermal switch - Google Patents

Abstract

PURPOSE:To enable switching a large amount of current at a given temperature and make a switch compact by using a superconductor showing a superconducting mode at the temperature and floating on repulsion against a permanent magnet, and a conductor shorted via the superconductor in an afloat condition. CONSTITUTION:At a temperature level equal to or less than a given temperature, a superconductor 5 repulses a permanent magnet 4 due to Meisner effect, thereby short circuiting a first conductor 6 and a second conductor 7 for switching operation. In this case, the superconductors have no resistance and a large amount of current can be made to flow without any loss. At a level exceeding the given temperature, the superconductor 5 loses superconducting characteristics and does not repulse the permanent magnet 4. Consequently, the first conductor 6 and the second conductor 7 are away from each other and a current flow is interrupted.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application The present invention relates to a temperature switch that controls current at a given temperature.

BACKGROUND OF THE INVENTION Conventionally, in order to perform a switching operation at an arbitrary temperature and to allow a large current to flow, an element (such as a bimetal) that detects the temperature and performs a switching operation and a relay for large currents are required.

An example of the conventional temperature switch mentioned above will be described below with reference to the drawings.

FIG. 2 shows a schematic configuration of a conventional temperature switch. Second
In the figure, 1 is a small signal temperature switch, which performs a switching operation at an arbitrary temperature.

2 is a transistor, and the small signal temperature switch 1
The switching operation is performed in synchronization with the Reference numeral 3 denotes a large current relay, which performs a switching operation in response to a signal from the transistor 2 to control the large current in the circuit.

The operation of the temperature switch configured as described above will be described below.

First, if the temperature is above an arbitrary temperature, the small signal temperature switch 1
is in the OFF state, so the transistor 2 is also in the OFF state, and the large current relay 3 is also in the OFF state.
FF" state. Therefore, no current flows through the circuit.Next, below an arbitrary temperature, the small signal temperature switch 1 is in the "ON" state, and therefore the transistor 2 is also in the "ON" state. The large current relay 3 is also 'ON'
state.

Therefore, current flows through the circuit.

Problems to be Solved by the Invention However, with the above configuration, in order to perform switching operation at an arbitrary temperature and also to flow a large current, it is necessary to use an element (such as a bimetal) that detects the temperature and performs switching operation, and a device for large current. It has the drawbacks of requiring a relay and being large in size.

In view of the above drawbacks, the present invention provides a compact superconducting temperature switch capable of switching a large current at any temperature.

Means for Solving the Problem In order to achieve this object, the superconducting temperature switch of the present invention comprises a permanent magnet, a superconductor that exhibits a superconducting state at a given temperature and floats by repelling the permanent magnet, and a superconductor that floats. It consists of a conductor that is short-circuited by the body.

Function: With this configuration, at an arbitrary temperature or below, the superconductor repels the permanent magnet due to the Meissner effect, thereby shorting the conductor and performing a switching operation. At this time, the superconductor has zero resistance, allowing a large current to flow without loss.

At a certain temperature or higher, a superconductor loses its superconducting state, so the conductor becomes an oven state and no current flows.

EXAMPLE An example of the present invention will be described below with reference to the drawings.

FIG. 1 shows a configuration diagram of a superconducting temperature switch in one embodiment of the present invention. In FIG. 1, 4 is a permanent magnet. 5 is a superconductor and exhibits a superconducting state below an arbitrary temperature. 6 is a first conductor, and 7 is a second conductor.

The operation of the superconducting switch configured as above will be described below.

First, below an arbitrary temperature, the superconductor 6 repels the permanent magnet 4 due to the Meissner effect, thereby shorting the first conductor 6 and the second conductor 7 to perform a switching operation. At this time, since the superconductor has zero resistance, it is possible to flow a large current without loss. Further, at a temperature higher than an arbitrary temperature, the superconductor 5 attempts to lose its superconducting state and does not repel the permanent magnet 4, so that the first conductor 6 and the second conductor 7 are in an open state. No current flows.

As described above, according to this embodiment, by providing a permanent magnet, a superconductor that exhibits a superconducting state at an arbitrary temperature and floats by repelling the permanent magnet, and a conductor that is short-circuited by the floated superconductor, , the switching operation can be performed at any temperature, and since the superconductor has zero resistance at this time, it is possible to realize a compact temperature switch that can flow a large current without loss.

Note that S is a material that exhibits superconductivity at room temperature.
r B a YCu 307-δ is known (
Ihara et al., JAPANESE Journal Op Applied Physics (TAPANESE l0URNAL 0F
APPLIED PHYSIC3), Vol, 26.
A8.

August, 1987, PP, 167-
171). During production, first the raw material powders are pulverized and mixed. It is calcined at 920° C. in air for 5 hours, then crushed and edge-rolled three times. Shape the powder and
Sinter by heating at 00° C. in air for 6 hours and cooling in a furnace.

The sintered body produced in this way was 338K (65t
E) shows the superconducting phenomenon.

Effects of the Invention As described above, the present invention provides a permanent magnet, a superconductor that exhibits a superconducting state at any temperature and floats by repelling the permanent magnet, and a conductor that is short-circuited by the floated superconductor. , a small temperature switch capable of switching a large current at any temperature can be provided, and its practical effects are significant.

[Brief explanation of the drawing]

FIGS. 1a and 1b are block diagrams showing the state of a superconducting temperature switch according to an embodiment of the present invention below and above an arbitrary temperature, and FIG. 2 is a block diagram of a conventional temperature switch. 4...Permanent magnet, 5...Superconductor, 6
...First conductor, 7...Second conductor.

Claims (1)

[Claims] A superconducting temperature switch comprising: a permanent magnet; a superconductor that exhibits a superconducting state at a given temperature and floats by repelling the permanent magnet; and a conductor that is short-circuited by the floated superconductor.