| 摘要 |
A magnetic core (3) surrounded by a coil (1, 2) bears a first pole shoe (4) forming a large-surface air-gap with two zones (5a, 6a) of two armatures (5, 6) fixed to one another and disposed magnetically in parallel. The core (3) is continued beyond the coil and at this end bears a second pole shoe (9) which together with two other zones (5c, 6c) of the armatures forms a second large-surface air-gap disposed magnetically in series with the first. |
