JPH04337300A - Superconducting deflection magnet - Google Patents

Abstract

PURPOSE:To provide a superconducting deflection magnet capable of suppressing the occurrence of quenching by providing a vacuum duct with a refrigerant passage on a superconducting wire coil. CONSTITUTION:A thin plate 4a is welded in close contact with the outer periphery of a vacuum duct 4 to form a refrigerant passage 5 with a square cross section. Liquid helium flows as a refrigerant in the passage 5 of the vacuum duct 4, not only the duct 4 but also a superconducting wire coil 1 is cooled at the extremely low temperature state via the thin plate 4a via the heat conduction by the temperature of the liquid helium. The coil 2 is efficiently cooled because it is cooled not merely via an epoxy resin outer film 3. A superconducting deflection magnet can suppress the occurrence of quenching, and the synchrotron radiation light with stable intensity can be provided.

Description

[Detailed description of the invention]

0001

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a superconducting deflection magnet used for deflecting the traveling direction of electrons in a synchrotron radiation generator.

0002

[Prior Art] Electrons are accelerated in an internal cavity in an ultra-high vacuum state of a vacuum duct configured in an annular shape, and the traveling direction of the electrons is deflected at a curved portion of the vacuum duct. There is a synchrotron radiation generating device that extracts synchrotron radiation emitted from the synchrotron radiation to the outside and utilizes it. Conventionally, in the above device, a coil made of superconducting wire is provided in the curved portion on the outer peripheral surface of the vacuum duct in order to generate a magnetic field for deflecting the traveling direction of electrons. For example, the superconducting wire coil disclosed in Japanese Patent Application No. 1-069798 and provided as described above as shown in FIG. It is molded with a covering epoxy resin and fixed to the outer peripheral surface of the vacuum duct 1. The outer peripheral side of the epoxy resin outer skin 3 is filled with liquid helium for cooling the superconducting wire coil 2 in order to bring the superconducting wire coil 2 into a superconducting state. It should be noted that other coils, collars, etc. are provided on the outer peripheral surface side of the epoxy resin outer skin 3, but these are omitted in FIG.

0003

[Problems to be Solved by the Invention] As mentioned above, the superconducting wire coil 2 is cooled with liquid helium, but since the cooling is performed indirectly via the epoxy resin outer skin 3, the cooling efficiency is not necessarily good. In particular, synchrotron radiation light emitted from electrons is irradiated onto the inner peripheral surface of the vacuum duct 1, so that the temperature of the vacuum duct 1 rises, and the temperature of the superconducting wire coil 2 also rises due to the heat conduction. Therefore, a so-called quench, in which the superconducting wire coil 2 ceases to be in a superconducting state, is likely to occur, and if a quench occurs, there is a problem that synchrotron radiation cannot be generated. The present invention was made to solve these problems, and an object of the present invention is to provide a superconducting deflection magnet that can suppress the occurrence of quenching.

0004

[Means for Solving the Problems] The present invention provides a superconducting deflection magnet equipped with a superconducting wire coil used in a superconducting state to generate a magnetic field for deflecting the traveling direction of electrons passing through an ultra-high vacuum. , characterized by comprising a vacuum duct having a refrigerant flow path.

[0005]

[Operation] With this configuration, the vacuum duct is cooled by the refrigerant flowing through the flow path, so it is possible to suppress the heat generated by synchrotron radiation irradiation from being conducted to the superconducting wire coil. At the same time, it can assist in cooling the superconducting wire coil from the outside, and acts to suppress the occurrence of quench in the superconducting wire coil.

[0006]

[Example] The vacuum duct 4 described below, which is used in the superconducting deflection magnet of the present invention, is a vacuum duct at a bent part that deflects the traveling direction of electrons among the vacuum ducts constituting the synchrotron radiation light generating device. It is. 1 to 4 showing one embodiment of such a vacuum duct 4, on the outer peripheral surface of the vacuum duct 4, as shown in FIG. A concave groove 5a having an appropriate depth is formed along the axial direction of the vacuum duct 4. Groove 5 on the outer peripheral surface of vacuum duct 4
Although the formation position of a is arbitrary, as shown in FIG.
In order to effectively cool the superconducting wire coil 2, a plurality of ducts may be formed at appropriate intervals in the circumferential direction of the duct 4 at a position facing the superconducting wire coil 2, and synchrotron radiation light emitted from electrons may be irradiated with the duct 4. They may be formed intensively at locations corresponding to the inner circumferential surface of the duct 4.

By welding a thin plate 4a to the entire outer peripheral surface of the vacuum duct 4 in which the groove 5a is formed, as shown in FIG. A refrigerant passage 5 having a cross-sectional shape is formed. Both ends of such a cooling passage 5, that is, both ends of the vacuum duct 4 in the axial direction as shown in FIG. By drilling a hole in the thin plate 4a near the flange 7 provided in the refrigerant inlet/outlet 6
is formed.

Further, as shown in FIG. 4, the refrigerant inlet/outlet 6 of the refrigerant passage 5 may be provided on the outer surface of the flange 7 by extending the refrigerant passage 5 to the flange 7 and providing a passage inside the flange 7. The refrigerant inlet/outlet 6 thus formed is connected to liquid helium, which is a refrigerant, existing outside the superconducting wire coil 2 , and liquid helium flows through the refrigerant passage 5 . Note that FIG. 1 does not show any components such as a coil in the outer circumferential direction of the epoxy resin sheath 3, and FIGS. Although not shown, the outer circumferential direction of the epoxy resin outer skin 3 or the thin plate 4a is also described in Japanese Patent Application No. 1-06979 in the same way as in FIG.
The components disclosed in No. 8 are provided. Further, the outer circumferential side of the epoxy resin jacket 3 is filled with liquid helium, and the superconducting wire coil 2 provided in contact with the outer circumferential surface of the vacuum duct 4 is cooled by the liquid helium, as in the conventional case.

With this configuration, the vacuum duct 4
Since liquid helium, which is a refrigerant, flows through the refrigerant passage 5, the vacuum duct 4 is heated by heat conduction due to the temperature of the liquid helium.
Of course, the superconducting wire coil 2 is also cooled to an extremely low temperature via the thin plate 4a. Therefore, since the superconducting wire coil 2 is not cooled only through the epoxy resin outer sheath 3 as in the conventional case, cooling is performed efficiently. Therefore, the superconducting deflection magnet of this example can suppress the occurrence of quenching and can obtain synchrotron radiation light of stable intensity.

The vacuum duct 4 having the refrigerant passage 5 is particularly effective for superconducting deflection magnets using the epoxy resin outer cover 3 as described above, but it is also useful for superconducting deflection magnets of a type in which the superconducting wire coil is not molded with epoxy resin. Even when used as a vacuum duct constituting the non-molded type superconducting deflection magnet, the effectiveness of the vacuum duct in the above embodiment is fully recognized as it can suppress the temperature rise of the duct due to irradiation with synchrotron radiation light. It can also be used.

[0011]

[Effects of the Invention] As detailed above, according to the present invention, since the vacuum duct is cooled by the refrigerant flowing through the flow path,
The generation of heat conducted to the superconducting wire coil can be suppressed, and the cooling from the outside of the superconducting wire coil can be assisted, and the occurrence of quench in the superconducting wire coil can be suppressed.

[Brief explanation of drawings]

FIG. 1 is a cross-sectional view of a vacuum duct portion constituting an embodiment of a superconducting deflection magnet of the present invention.

FIG. 2 is an enlarged view showing the refrigerant passage shown in FIG. 1.

FIG. 3 is a longitudinal sectional view of a vacuum duct showing an example of a refrigerant inlet/outlet of a refrigerant passage formed in the vacuum duct constituting the superconducting deflection magnet of the present invention.

FIG. 4 is a longitudinal sectional view of a vacuum duct showing an example of a refrigerant inlet/outlet of a refrigerant passage formed in the vacuum duct constituting the superconducting deflection magnet of the present invention.

FIG. 5 is a cross-sectional view of a vacuum duct portion of a conventional superconducting deflection magnet.

[Explanation of symbols]

2... Superconducting wire coil, 3... Epoxy resin outer cover, 4... Vacuum duct, 4a... Thin plate, 5... Refrigerant passage.

Claims (2)

[Claims] Claim 1: A superconducting deflection magnet equipped with a superconducting wire coil used in a superconducting state to generate a magnetic field for deflecting the traveling direction of electrons passing through an ultra-high vacuum, the vacuum having a coolant flow path. A superconducting deflection magnet characterized by being equipped with a duct. 2. A superconducting deflection magnet in which a superconducting wire coil used in a superconducting state is molded with resin from the outer circumferential side of the coil to generate a magnetic field to deflect the traveling direction of electrons passing through an ultra-high vacuum. A superconducting deflection magnet characterized by comprising a vacuum duct having a coolant flow path.