| 摘要 |
<p>PROBLEM TO BE SOLVED: To effectively suppress a leakage flux by spirally winding a primary coil wire on a coil bobbin so as to return the wire by winding, with the winding start position and the winding end position on the same side. SOLUTION: At the time of winding a primary coil 12 on a coil bobbin 13, a coil wire 121 is spirally wound on the axis part of the coil bobbin 13 so as to return the wire by winding, with a substantial axis length which allows the length of the primary coil and the length of a secondary coil to be almost equal and with a winding start position 1S and a winding end position 1E on the same side. Then, on the axis part of the coil bobbin 13, a guide groove 17 which spirally winds the coil wire 121 and a pin 18 which supports the returning part of the coil wire 121 are formed. Thus, a leakage flux is effectively suppressed, and voltage transforming efficiency between the primary side and the secondary side is improved.</p> |
