GB899177A - A high-voltage glass-blast circuit-breaker - Google Patents

Abstract

899,177. Gas-blast switches. LICENTIA PATENT-VERWALTUNGS G.m.b.H. March 9, 1959 [March 10, 1958], No. 8056/59. Class 38 (5). A gas-blast circuit-breaker comprises an arcquenching chamber 1 of slot-like cross-section in which fixed and rectilinearly-movable contacts 2, 3 are arranged so that the arc 5 heats the air in space 4 to produce an upward arcextinguishing blast past the arcing contacts 6 and insulating members 7. In a modification, Fig. 2 (not shown), an additional air compartment is formed beneath the lower end of the quenching chamber and is connected thereto by a narrow passage containing barriers which further restrict its size. Figs. 3 and 4 show a breaker having a pivoted contact 3, an additional compartment 4, a cooler 11, partitions 12 and a filter 14 consisting of a fine fabric of wire or textiles. This filter may be replaced by a restricted passage 15, Fig. 5, in which the chamber walls are covered by a gas-evolving material 16, and the action of a soot arrester 17 is improved by a liquid 18 such as water. The surface leakage path between the contacts of the breaker shown in Fig. 1 is increased by a number of deep grooves formed in the walls of the quenching chamber, Figs. 6 and 7 (not shown). In another modification Fig. 8 (not shown), the width of the pivoted contact is made equal to that of the quenching chamber, whose walls have recesses to increase the air flow past the movable contact when it is opened. To avoid the need for recesses, the moving contact may comprise a two-armed lever pivoted in the centre of the chamber, each arm cooperating with a fixed contact, Fig. 9 (not shown).