GB626842A - Improvements in or relating to gas-blast electric circuit-breakers - Google Patents

Abstract

626,842. Gas-blast switches. REYROLLE: & CO., Ltd., A., and BLANCH, N. R. Sept. 9, 1947, No. 24763. [Class 38(v)] In a gas-blast circuit-breaker comprising a unit including the main contacts F, H, an associated nozzle G, and a contact enclosure F' whose interior is in open communication with the reservoir housing the unit, and wherein a blast valve, formed by the exhaust valves B, B' is opened in timed relation with the contact-operating means so that arc-extinguishing gas flows over the separating contacts, the reservoir is formed by two complementary and mutuallydetachable parts C', C<SP>2</SP>, the part C<SP>1</SP> carrying the unit and housing the operating means wholly, and the second part C<SP>2</SP> carrying the terminals D<SP>2</SP>, D3 and housing the unit. The circuit-breaker is closed by electromagnetically opening a valve N<SP>2</SP> torelieve the back pressure on a piston K' which moves upwardly to rotate a lever K<SP>2</SP> clockwise and close the contacts. To open the circuit-breaker, a pilot valve K<SP>7</SP> is opened to relieve the back pressure on a second piston K<SP>3</SP> which moves downwardly in cylinder K<SP>5</SP> to separate the contacts. As the contacts separate, the valve B<SP>1</SP> is opened to relieve the back pressure on a diaphragm B which lifts to allow a gas blast upwards through a nozzle F<SP>4</SP>, carrying an auxiliary electrode F<SP>5</SP>, and through conduits G<SP>1</SP> to atmosphere. An arc is then drawn between H and F<SP>5</SP>, thereby inserting a series resistance F<SP>6</SP>, and this arc is extinguished by the gas blast through nozzle G when the contact H moves above it. Three conduits G<SP>1</SP> are held between a plate E<SP>1</SP> and a cooling plate E<SP>3</SP> by three tie rods E<SP>2</SP>, the conduits and rods being arranged on a circle concentric with contact H which has a guide H<SP>1</SP> supported by a spider attached to the rods E<SP>2</SP>. The contacts are connected to the terminals D<SP>2</SP>, D3 by contacts H<SP>6</SP> and F<SP>8</SP> carried by the reservoir part C<SP>1</SP>. The circuitbreaker shown forms one phase of a threephase circuit-breaker, the pivot K of the lever K<SP>2</SP> passing through a sleeve opening into each of the three reservoirs, so that their interiors are connected.