ELECTROMAGNETIC INDUCTION-TYPE SENSOR COIL AND METHOD OF MANUFACTURING THE SAME

摘要

PROBLEM TO BE SOLVED: To easily perform an adjusting operation for taking the electromagnetic balance of two differentially connected sensor coils and to efficiently manufacture an electromagnetic induction-type sensor coil. SOLUTION: The electromagnetic induction-type sensor coil is constituted to be provided with a coil bobbin 21A on which a transmitting coil S1 and a receiving coil R1 are wound, a coil bobbin 21B on which a transmitting coil S2 and a receiving coil R2 are wound and an adjusting ring 11 which is formed of a magnetic substance near the contact part of the coil bobbin 21A with the coil bobbin 21B. The adjusting ring 11 can be moved along the center axis direction of the coil bobbins 21A, 21B, and it is fixed to the contact part of the coil bobbins 21A, 21B in a position which can obtain the electromagnetic balance.