| 摘要 |
A contactor has a movable contact assembly which is connected to the magnet armature in such a way that the contact assembly moves translatorily in the same direction as the armature between a closed and an open position. The contact assembly comprises a movable main contact with relatively small contact elements of silver alloy and a movable arcing contact with contact elements of silver-free material. The arcing contact makes and breaks the main current, whereas the main contact carries almost the entire current in closed position. The contacts have separate contact pressure springs. The contactor has at least one opening spring which is obliquely directed in relation to the direction of motion of the armature and is clamped between two bearing points, of which one is fixed whereas the other, upon operation of the electric switch, is displaced together with the armature in the same direction of motion. Thereby, the component of the spring force which counteracts the attractive force of the magnet will be reduced upon closing, which means that, despite double contact and spring systems, it is possible to use an operating magnet with relatively small dimensions. |
