| 摘要 |
PURPOSE:To stabilize the rotating speed of an engine by making the cross section of the root portion, where the field of the magnetic pole portion of the first and second yoke member pair in a similar shape, larger and making the cross section of the tip portion, where less field occurs, smaller. CONSTITUTION:The first and second yoke members 12, 13. fitted together, have a common magnetic pole portion 14b formed in an approximately cylindrical shape. Electromagnetic coils 8A, 8B are housed in the first and second yoke members 12, 13, respectively. The cross section of the root portion, where the field of the magnetic pole portion 14b of the first and second yoke members 12, 13 is concentrated, is made larger, while the cross section of the tip portion, where less field occurs, is made smaller. This allows a large field corresponding to the amount of current in the coils 14A, 14B, resulting in the paralleled property of duty flow rate. It is thus possible to stabilize the rotating speed of an engine. |
