Operating mechanism for a multipolar fault-current protective switch with a rotary crossbar.

摘要

A differential switch (10) includes a switching bar (32) arranged as a contact-carrying rotary shaft (30, 26), a summer transformer (46) associated with a triggering relay (54) with automatic rearming, and a control mechanism (34) with a handle (64) and latch (88). The end (74) of the link rod (70) situated opposite the axis of articulation (72) of the knuckle joint interacts upon establishing the mechanical link with a first bearing stop (76) of the engaging lever (78) and a second bearing stop (80) of the switching bar (32). The relay (54) transmits the triggering order to the latch (88) via a triggering lever (98) associated with an intermediate mechanical amplifier. This results in a mechanism with three stages for stepping down forces between the relay (54) and the bar (32), which makes it possible to reduce the triggering energy.