Single-pole switching unit and switching unit comprising one such unit

Abstract

The invention relates to a single-pole switching unit having a housing comprising a moving contact bridge and a pair of fixed contacts cooperating with said moving contact bridge and respectively connected to a current intake conductor, two electric arc cutoff chambers respectively opening onto an open volume of the moving contact bridge, each cutoff chamber being connected to at least one exhaust channel (). The exhaust channel () comprises a rotating gate () designed to be rotated around an axis substantially perpendicular to the exhaust channel () by the passage of switching gases. The rotating gate () comprises an edge () positioned across from an inner wall () of the exhaust channel, in the first obstruction position. The arrangement of the rotating gate () and the inner wall () is such that the distance between said edge () and said inner wall () remains constant and equal to said first distance up to a first threshold value of the angle of rotation of the rotating gate (), then increases linearly up to a second rotation angle threshold value corresponding to complete opening of the discharge channel. The invention also relates to a switching unit comprising at least one single-pole switching unit.