Power resistor, method of manufacturing the same, and power circuit breaker
AssigneeKabushiki Kaisha Toshiba
InventorsMotomasa Imai, Naoki Shutoh, Fumio Ueno
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Abstract
Disclosed is a power resistor which has a large heat capacity per unit volume and an appropriate and stable electrical resistance, and in which the resistance changes little with time due to surge absorption. This power resistor includes a sintered body containing aluminum oxide and carbon, and a pair of electrodes formed on the two opposing surfaces of the sintered body. This sintered body consists of first regions containing a small amount of carbon or not containing carbon and second regions containing a larger amount of carbon than in the first regions and so arranged as to be connected to the electrodes.
Claims9
A power resistor comprising:
- a sintered body containing aluminum oxide and carbon;
- and
- a pair of electrodes formed on two opposing surfaces of said sintered body;
- wherein said sintered body consists of a plurality of first regions and a plurality of second regions containing carbon in an amount larger than in each of said first regions;
- said second regions having a mean grain size of aluminum oxide particles smaller than that of the aluminum oxide particles in said first regions;
- said plurality of first regions occupying a greater part by weight of said sintered body, with said plurality of second regions occupying the remaining part by weight of said sintered body;
- and
- the carbon present in said second regions electrically connecting said second regions and said pair of electrodes and existing at triple points of aluminum oxide particles in said second regions.
Dependencies are inferred from the claim text.