| 摘要 |
PURPOSE:To improve the operating characteristics of a magnetic circuit at the fully wire driving time by providing a shunt plate made of a soft magnetic material immediately at the outside of a coil, thereby enhancing the preventing efficiency of wasteful increase in the shunt magnetic path length. CONSTITUTION:A shaft plate 12 made of a soft magnetic material is wound externally of a coil. When only the coil of right side is energized, a composite magnetic flux of a magnetic flux PHI11 due to an exciting current and PHIIL1 partly branched to the adjacent magnetic circuit cancels PHIM1, thereby performing a printing operation. The presence of the PHIL11 is effective to reduce the drive current and to increase the variable amount of the magnetic flux. Further, the magnetic flux PHIIS1 passing through the shunt plate is added to further improve the operating characteristics. When all coils are energized, the branching magnetic flux PHIIL1 is eliminated, but the magnetic flux passing the shunt plate is presented, and the PHIIS1 is superposed on the magnetic flux PHII1 to cancel the PHIM. |
