Fluid-blast type circuit interrupter

Abstract From the Canadian patent

A circuit interrupter comprises a pair of separable contacts in an arc extinction chamber filled with an arc-extinguishing fluid; a pressurizing chamber for storing the fluid pressurized in an arc space in which the arc is formed by the separating contacts; and speed control means for controlling the speed of separation of the contacts in at least two steps, said speed control means being connected to a driving system for the contacts wherein the fluid is discharged through the arc space out of the arc extinction chamber after the contacts have separated by a specific distance and the arc is interrupted by puffing the fluid.