| 摘要 |
PURPOSE:To reduce the impedance of the whole coil and to make the output higher reducing the size, by using more than two pieces of wire, by making coil blocks winding the respective pieces of wire around magnetic materials, and by composing one exciting coil by the assemblage of these coil blocks. CONSTITUTION:Around a magnetostrictive bar 11, three coil blocks divided vertically to the longitudinal direction (axial direction), namely, the first coil 12, second coil 13, third coil 14 are wound and constitute one exciting coil C. In this way, the three coil blocks have winding start tips 12a, 13a, 14a and winding end 12b, 13b, 14b respectively, and the respective winding start tips 12a, 13a, 14a are bound together into one and make an input tip I. On the other hand, the winding end tips 12b, 13b, 14b are bound together into one making an output tip O, and the input tip I and output O are connected to a sound input section 15. |
