Abstract:
Discloses an arc chute having spaced sidewalls of a first insulating material and arc runners having most of their active surfaces of a refractory metal. Between one of the runners and the sidewalls are two face plates of a second insulating material, such as glass-bonded mica, that is characterized by low gas evolution and greater surface resistivity than said first material under high humidity conditions. The face-plate surfaces adjacent an arc are shielded from the arc by a thermally-sprayed coating of refractory ceramic insulating material on said surfaces.
Abstract:
Discloses a vacuum-type circuit interrupter having its contacts formed of a porous refractory metal matrix and an alloy of copper and bismuth filling the pores of the matrix, the percentage of bismuth being less than 2 percent by weight of the copper-bismuth alloy.
Abstract:
Discloses a circuit breaker with a pair of contacts that are located in a fluid medium and are relatively movable into and out of engagement with each other. Each of these contacts comprises a porous skeleton of a refractory material, such as tungsten or tungsten carbide, and an alloy of silver and bismuth filling the pores of the skeleton. The percentage of bismuth is less than 2 percent by weight of the silver-bismuth alloy.
Abstract:
Discloses a vacuum-type electric circuit interrupter having its contacts formed of a porous refractory metal matrix and an alloy filling the pores of the matrix consisting essentially of copper, aluminum, and bismuth. In the alloy, the aluminum is present in a quantity of between 9 and 15 percent by weight of copperaluminum, and the bismuth is present in a quantity of less than 5 percent by weight of the total alloy.
Abstract:
Discloses a method of making an electrode that involves providing a cup-shaped shell of sintered refractory particles, placing within the shell non-refractory backing metal, heating in a reducing atmosphere to melt the backing metal and cause it to infiltrate the shell, replacing the reducing atmosphere with an inert environment, holding the assembly in the inert environment for a sufficient period to remove a substantial quantity of dissolved gases from the molten backing metal, and then cooling within said inert environment to solidify said backing metal and remove additional dissolved gases.
Abstract:
A vacuum-type circuit interrupter comprising a pair of contacts relatively movable into and out of engagement, the contacts having circuit-making and -breaking regions formed of an alloy consisting essentially of copper-beryllium and bismuth, the beryllium being present in a quantity of between 2 percent and 19 percent by weight of the copper-beryllium and the bismuth being present in a quantity of less than about 5 percent by weight of the total alloy but in a sufficient quantity to inhibit contact welding.