Electric circuit breaker with electromagnetic-assist means for opposing magnetic contact-separating forces

An electric circuit breaker comprising:

• (a) a first contact rod and a first contact fixed thereto,
• (b) a second contact rod and a second contact fixed thereto, said second contact being movable into engagement with said first contact to close said circuit breaker and movable out of engagement with said first contact to open the circuit breaker and interrupt the circuit therethrough, said second contact remaining in engagement with said first contact while said circuit breaker is in its fully closed position,
• (c) means for movably mounting said first contact for movement with said second contact:
• (i) following initial engagement of said contacts during the final portion of closing motion of said contact and (ii) during the initial portion of opening motion of said second contact,
• (d) first electromagnetic-assist means coupled through said first contact rod to said first contact for developing while said contacts are engaged a magnetic force on said first contact which varies directly in accordance with the current through said contacts and which urges said first contact toward said second contact,
• (e) second electromagnetic-assist means coupled through said second contact rod to said second contact for developing while said contacts are engaged a magnetic force on said second contact which varies directly in accordance with the current through said contacts and which urges said second contact toward said first contact,
• (f) and means for blocking motion of said first contact with said second contact after said initial opening motion of said second contact and for preventing during subsequent opening motion of said second contact the transmission of force from said first electromagnetic-assist means to said second contact.