| 摘要 |
An electric switch has an arc interrupter mounted in a housing between two main conductors. The interrupter comprises a fixed contact having a first arcing surface, a fixed electrode having a second arcing surface, an arc-driving coil and a movable contact, the surfaces and the coil being coaxial with one another and the contact being mounted for angular movement about a pivot axis between a make position and a break position. During opening of the interrupter, an arc is initially struck between the contacts after which it is transferred from the contact to the electrode. The coil, now being part of the arc current path, produces a magnetic flux which interacts with the arc so that it is driven around the axis between the surfaces. That movement of the arc assists in extinguishing the arc at an appropriate current zero. Ferromagnetic material forms part of the magnetic circuit of the coil. Two interrupters can be arranged in series between the main conductors. Alternatively, the interrupter can have two fixed contacts, two movable contacts and two coils. |
