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| Number | Title | Issue Date |
| 7417520 | Contactor for direct current and alternating current operation The invention relates to a contactor for direct current and alternating current operation with at least one contact point with a fixed contact and a movable contact, at least one permanent magnet, arranged adjacent to the contact point, for the generation of a perma... | 08/26/2008 |
| 4503302 | Arc interrupter 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 contac... | 03/05/1985 |
| 4376271 | Polarized DC contactors Means for causing the properly-polarized one of a pair of series-connected DC contactors to open before the other, depending upon the direction of load current flow. Load current is caused to link the magnetic circuit constituted by a contactor coil, fram... | 03/08/1983 |
| 4301340 | Electrical switchgear A pair of switches are disposed adjacent one another in a housing which contains the highly insulating gas sulphur hexafluoride. In a closed position of each switch, a pivotable contact arm engages fixed contact fingers to permit the flow of load current ... | 11/17/1981 |
| 4301341 | Electrical switchgear On opening of a circuit breaker, an end portion of a pivotable contact arm disengages from fixed contacts such that an arc is drawn therebetween radially across the pole face of a field coil, the end portion of the contact arm moving transversely to the f... | 11/17/1981 |
| 4273977 | Circuit interrupter A circuit interrupter consisting of a pair of contacts being relatively movable to be detachable in an arc extinct chamber filled with a fluid for arc extinction is disclosed. Also included are a chamber for storing the fluid pressurized in an arc space i... | 06/16/1981 |
