| 摘要 |
<p>PURPOSE:To prevent the reduction of the size of a heater from being interfered and to prevent the slipping-off of Mo fine wires thickly wound around the legs of a primary coil by manufacturing such the primary coil, and secondary winding the primary coil. CONSTITUTION:A primary coil 1 is obtained by primary winding a W wire at a specified pitch with a specified dia., and thickly winding Mo fine wires around only the portions to be legs, and then the coil 1 is secondary wound to obtain a desirably structured one. In this method, the portions of the coil 1 where the fine wires 2 are not thickly wound are secondary wound so that the pitch of secondary winding can be fully narrowed and the reduction of size can be easily attained. Further, as the fine wires 2 at the legs are wound around a primary coil at the same time when the primary winding is carried out, they are thickly wound without the slipping-off.</p> |
