| 摘要 |
PROBLEM TO BE SOLVED: To prevent dispersion of pitches, in a wire which is spirally wound on the outer periphery of a bobbin for primary coil and to keep the performance /level of an ignition coil to be constant. SOLUTION: In the primary coil for ignition coil for an internal combustion engine, a primary wire 1 is spirally wound to a wire winding part 3 at the outer periphery of the bobbin for a primary coil 2. Spiral projections 6 are installed in the wire winding part at the outer periphery of the bobbin for primary coil, at a pitch which is almost identical to the diameter D of the primary wire, and the primary wire is spirally wound along the intervals of the projections. |
