JPH0559400B

• Main Authors: GUNJI MINORU, SAITO MAKOTO
• Format: Patent
• Language: English
• Published: 30.08.1993
• Edition: 5
• Subjects: GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; NUCLEAR ENGINEERING; NUCLEAR PHYSICS; NUCLEAR REACTORS; PHYSICS; REDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGYGENERATION, TRANSMISSION OR DISTRIBUTION; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS; TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINSTCLIMATE CHANGE

PURPOSE:To surely cut off control rods at the time of temperature abnormal increase by incorporating heat sensitive magnetic materials among a coil and all the attraction faces. CONSTITUTION:A first iron core is rotation symmetry, structure in which a center leg part 20a and a peripheral cylindrical part 20b are connected in the upper part thereof is made and a coil is wound on the center leg part 20a. The lower end faces of the leg part 20a and the cylindrical part 20b are attraction faces respectively and a second circular plate-like iron core 22 which becomes are an armature is attracted. Further, respective heat sensitive magnetic materials 26a, 26b are provided between a coil attaching part and an attraction face of the iron core 20. In the case where temperature does not reach Curie temperature, magnetic flux which generates in the coil 24 almost passes in a magnetic circuit because the magnetic materials 26a, 26b are ferromagnetic substances and sufficient attraction works on an attraction face X, Y to hold control rods. Further, when circumstance temperature exceeds a Curie point, the magnetic materials 26a, 26b lose magnetization and the magnetic flux density of the attraction faces X, Y is remarkably lowered. As the result, the attraction decreases to cur off the iron core, which drops to stop a reactor.