Patent Number: 061920967
Section: abstract

A magnetostrictive wire control rod position detector assembly which will allow nuclear reactor output to be increased, control performance to be improved, and peripheral equipment to be rationalized by continuously and accurately detecting the position of a control rod in a reactor core is provided. A magnetostrictive wire control rod position detector assembly (20) comprises: a magnet or magnets (21) mounted on a non-magnetic portion of a movable member (3) which is free to move in the longitudinal direction on the inside of a cylindrical member (1) and is partly composed of a non-magnetic material; a magnetostrictive wire detector (22) longitudinally mounted on the outer circumference of said cylindrical member, which is provided with a receiver (26); and a pulsed current generator circuit (37) which supplies a pulsed current from the receiver end to the magnetostrictive wire of the magnetostrictive wire detector. When the magnetic field generated in the magnetostrictive wire by the pulsed current approaches the magnetic field of the magnet or magnets on the movable member, mutual interference between the magnetic fields generates torsional waves in the magnetostrictive wire, and the physical position of the movable member can be accurately measured if the propagation time of the torsional waves is measured by the receiver.