JPH02252275A - Heat shield plate - Google Patents

Abstract

PURPOSE:To prevent the heat transfer phenomenon from occurring by a method wherein the title heat shield plate is provided with a high resistant member in higher electric resistance than that of a heat shield member while both ends of heat shield member are connected to the high resistant member to restrict the generation of an eddy current. CONSTITUTION:The title heat shield plate is composed of a Cu or Al made band type heat radiation shield member 1, a fiber reinforced plastic FRP 2 making the said member 1 ring-shaped and connecting both ends thereof as well as bolts 3 connecting the FRP 2 to the member 1. Besides, an aluminum bonding tape 4 is bonded onto the surface of the FRP 2 so as to electrically disconnect the member 1 by the FRP 2 in higher resistance than that of the member 1. Through these procedures, any eddy current generated in the heat shield plate 1 can be prevented from running out thereby preventing the member 1 from being heated by Joule heat. At this time, the tape 4 fills the roles such as the reflection of the heat radiation, the prevention of the thermal radiation level from increasing and the reduction of incoming heat.

Description

[Detailed description of the invention] [Industrial application field] The present invention relates to a heat shield plate for a cryogenic container.

[Prior art] A superconducting magnet whose coil is cooled by liquid helium and generates a magnetic field by the superconducting effect is housed in a helium container containing liquid helium, and the helium container is a low-temperature container with high insulation properties. surrounded by. In this low-temperature container, the helium container is equipped with a plurality of heat shield plates to prevent radiant heat from the outside, and these shield plates are made of an electrically conductive material such as copper or aluminum.

On the other hand, a pulsed current is applied to the superconducting magnet, and as a result, a pulsed magnetic field (referred to as a pulsed magnetic field) is generated.

[Problems to be Solved by the Invention] In conventional superconducting magnets, eddy currents are generated in the heat shield plate of the low temperature container due to the pulsed magnetic field. This eddy current generates Joule heat in the shield plate, causing a heat intrusion phenomenon.

[Means for Solving the Problems] According to the present invention, there is provided a band-shaped heat shield member and a high resistance member having an electrical resistance larger than the electrical resistance of the heat shield member, and both ends of the heat shield member are connected to each other. A heat shield plate characterized in that it is connected by the high-resistance member is obtained.

[Function] In the heat shield plate according to the present invention, in order to cut off eddy current, FRP is used for a part of the shield plate, and a portion with high electrical resistance is created in a closed circuit for eddy current.

[Example] Next, the present invention will be described in more detail with reference to the drawings showing an example of the present invention.

Referring to FIG. 1, a heat shield plate according to an embodiment of the present invention includes a band-shaped heat radiation shield member 1 made of copper (Cu) or aluminum (CAD), and a ring-shaped shield member 1 connected at both ends thereof. It is composed of a fiber reinforced plastic (hereinafter referred to as FRP) 2 and a bolt 3 made of FRP that connects the shield member 1 and the PRP 2.

Copper or aluminum is vapor-deposited on the surface of the FRP 2, or an aluminum adhesive tape 4 is attached.

In this embodiment, the thermal radiation shield member 1 is made of PRP.
Since it is electrically disconnected by 2, eddy current does not flow, and therefore heat generation of the shield plate member due to eddy current can be prevented.

If the thermal radiation shielding member 1 is made only of FRP, the radiation coefficient will be high and the amount of thermal radiation will be large.

For this reason, in this embodiment, the surface of the FRP 2 is vapor-deposited with copper or aluminum having a low radiation coefficient, or an aluminum adhesive tape is attached.

Thereby, it is possible to reflect thermal radiation to the shield plate and reduce heat input.

[Effects of the Invention] As explained above, according to the present invention, when forming the heat shield member into an annular shape, both ends of the heat shield member are connected with a member having an electrical resistance larger than the electrical resistance of the heat shield member. eddy current is less likely to occur.

[Brief explanation of drawings]

FIG. 1 is a plan view of a heat shield plate according to an embodiment of the present invention. 1: Heat radiation shield member, 2: FRP, 3: Bolt, 4
aluminum adhesive tape.

Claims (1)

[Claims] 1. A heat shield comprising a band-shaped heat shield member and a high resistance member having an electrical resistance greater than the electrical resistance of the heat shield member, and both ends of the heat shield member are connected with the high resistance member. shield board.