Patent ID: 7045733

Claim:
A low-voltage circuit-breaker comprising at least one mobile contact ( 10 ), which can be coupled to/uncoupled from a corresponding fixed contact ( 20 ) and a positive-opening-operation device ( 30 ), said positive-opening-operation device ( 30 ) comprising: a moving element ( 40 ) associated to the mobile contact ( 10 ); a first kinematic chain ( 50 ) operatively associated to said mobile contact ( 10 ) and to an actuating device ( 11 ); and a second kinematic chain ( 60 ) associated to said moving element ( 40 ) and to said first kinematic chain ( 50 ), a first lever ( 51 ) being associated to the first kinematic chain ( 50 ) and a second lever ( 61 ) being associated to the second kinematic chain ( 60 ), said first and second levers ( 51 , 61 ) interacting with one another during the opening operation and being equipped with blocking devices ( 70 ) in the event of welding of the contacts ( 10 , 20 ) together.