Circuit breaker

A circuit breaker having means for compressing a quenching medium, comprising:

• a nozzle member, said nozzle member being made of an insulating material and having a main duct;
• a first contact piece, said first contact piece being slidingly accommodated in said main duct;
• a second contact piece, said second contact piece being fixedly connected to said nozzle member;
• a first blow duct, said first blow duct being included in said nozzle member and having a first blow orifice located at a first axial location;
• a second blow duct, said second blow duct being included between said nozzle member and said second contact piece and having a second blow orifice located at a second axial location, said second axial location being spaced from said first axial location;
• and
• an exhaust duct, said exhaust duct being included in said nozzle member and having an exhaust orifice located at a third axial location, said third axial location being disposed between said first and second axial locations;
• wherein when current flows through the circuit breaker said first and second blow orifices and said exhaust orifice are each covered by said first contact piece;
• and
• further wherein, when said current flow is interrupted, quenching medium is blown into said blow ducts and said first and second contact pieces move relative to each other such that said first and second blow orifices and said exhaust orifice are uncovered so that said quenching medium is blown through said first and second blow orifices and into said main duct, a first portion of said quenching medium being exhausted from said main duct through said exhaust orifice.