DEVICE FOR ARC-FREE SWITCHING OF ELECTRIC CIRCUITS

摘要

A device for arc-free switching of electric circuits has a contact switching unit (1), to a movable contact (7) of which are connected the emitters of transistors (6, 9) contained in a circuit (5) for protecting the contacts of the contact switching unit and connected, through their collectors, to the stationary contacts (8, 2) of the contact switching unit (1) thus forming electric circuits shunting the movable contact (7) with each of the stationary ones at the moment of switching. To the bases of the transistors (6, 9) are connected the cathodes of the diodes (12, 14), and the resistors (11, 13) contained, together with the stationary contacts (8, 2), in a unit (10) for controlling the contact protecting circuit. The anode of the diode (12) connected to the transistor (6) is connected to the stationary contact (2), whereas the anode of the diode (14) connected to the transistor (9) is connected to the stationary contact (8). The control unit (10) provides for controlling the transistors (6, 9) through the extreme and intermediate positions of the movable contact (7) thus ensuring the switching of two loads (4, 16).