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US 5,633,777 AGranted
Gas-filled, three-electrode overvoltage surge arrester for large switching capacities
AssigneeSiemens Aktiengesellschaft
InventorsJurgen Boy, Gerhard Lange
Life of this patent
Estimating the term…
Abstract
To adapt a three-electrode arrester having copper electrodes to high switching capacities (200 Amp a.c. current per discharge gap simultaneously for 11 cycles at 60 Hz), the following measures are provided: The cylindrical end electrodes have a volume of at least 60 mm.sup.3, given a ratio of length (L.sub.2) to diameter (D.sub.2) of less than 2.5; the middle electrode has the shape of a hollow cylinder with end regions of a reduced wall thickness; the middle electrode and the hollow cylindrical insulators are soldered to one another at the front ends.
Claims10
A gas-filled overvoltage surge arrester, comprising:
- a) two cylindrical end electrodes being made of copper, each having a flange-like base, and axially opposing one another, wherein a cylindrical section (L.sub.1, D.sub.1) of each of the end electrodes has a volume of at least 60 mm.sup.3, and an axial length (L.sub.1) of the cylindrical section is smaller than 2.5-times its diameter (D.sub.1);
- b) a middle electrode being made of copper, surrounding the two end electrodes over one section of their axial length, wherein the middle electrode has a hollow cylindrical design;
- and
- c) two hollow cylindrical insulators, each having a wall thickness of about 1 mm, and being disposed between the middle electrode and the bases of the end electrodes, wherein the middle electrode and the two hollow cylindrical insulators are soldered to one another at the front ends, an inner surface area of the middle electrode being provided in regions bordering the two insulators in each case with a radial graduation, and the middle electrode having a wall thickness (d.sub.1) in the area of the soldered connection points, which amounts at the most to 60% of the wall thickness (d.sub.3) of the insulators.
1 more element
Dependencies are inferred from the claim text.