Switchgear

A switchgear comprising in a housing containing an arc extinguishing gas,

• a stationary contact,
• a movable contact capable of contacting with and separating from said stationary contact, said movable contact and said stationary contact defining therebetween an arcing region in which an electric arc is generated when said contacts are separated;
• means for defining a gas storage chamber around said stationary contact communicated with said arcing region for storing the arc extinguishing gas increased in pressure by heat from the arc;
• an insulating nozzle attached to said gas storage chamber for defining an opening through which said movable contact movably extends and through which said arc extinguishing gas flows;
• and
• magnet means for generating a magnetic field in said opening of said gas storage chamber for rotating and elongating the electric arc generated between said stationary contact and said movable contact upon current interruption;
• said magnet means being an annular outer magnet disposed around said gas storage chamber, an inner magnet desposed within said gas storage chamber, and a magnetic material connecting said inner magnet to said outer magnet for short-circuiting the magnetic path therebetween.

A switchgear comprising in a housing containing an arc extinguishing gas,

• a stationary contact;
• a movable contact capable of contacting with and separating from said stationary contact, said movable contact and said stationary contact defining therebetween an arcing region in which an electric arc is generated when said contacts are separated;
• means for defining a gas storage chamber around said stationary contact communicated with said arcing region for storing the arc extinguishing gas increased in pressure by heat from the arc;
• an insulating nozzle attached to said gas storage chamber for defining an opening through which said movable contact movably extends and through which said arc extinguising gas flows;
• and
• magnet means for generating a magnetic field in said opening of said gas storage chamber for rotating and elongating the electric arc generated between said stationary contact and said movable contact upon current interruption;
• said magnet means including a first annular magnet mounted to said nozzle and a second annular magnet disposed outside of said stationary contact within said gas storage chamber.