Magnetothermal release mechanism associated with the mechanism of a miniature circuit breaker with an insulating casing.

摘要

1. Thermomagnetic trip release (10), associated with an opening mechanism of a molded insulated case miniature circuit breaker, comprising : - a first thermal trip release with a bimetallic strip (14) sensitive to overload currents, - a second electromagnetic trip release for protection against short-circuit currents, comprising a control coil (34) electromagnet (16), made up by helical winding of a deformable conductor having a preset rigidity, - and an adjustment device (52) of the thermal tripping threshold of the first trip release, characterized in that the coil (34) of said electromagnet is extended by a tail (44), arranged as an adjustable support part of the bimetallic strip (14), the foot (48) of the latter being inserted by soldering between said tail (44) and an electrical connection means (76, 80) with a contact pad, to cause the current to flow thickness-wise through the foot (48) of the bimetallic strip (14), and that the tail (44) comprises a hinge (60) between the junction point of the foot (48) of the bimetallic strip (14) and the coil (34), in such a way as to allow a relative movement of one part of said tail (44) due to the action of the thermal tripping threshold adjusting device (52), the other part, connected to the coil (34) remaining appreciably stationary.