Voltage surge protection device for electric meters

Claim 1

An electric meter, a combination of an enclosure including an insulating base, said base having a hole opening extending therethrough, an electro-responsive measuring unit mounted within said enclosure, a meter terminal extending through said base for connecting said measuring unit to a meter socket terminal and an external circuit to measure, and a voltage surge protection device comprising; a voltage responsive current limiter having opposite end electrodes and located in said hole opening so that one of said end electrodes is exposed toward the interior of said base and the other of said end electrodes is exposed toward the exterior of said base; an inner contact member mounted within said enclosure, said inner contact member electrically connected between said one end electrode and said meter terminal; an outer contact member made of a thin elongated electro-conductive material and carried on the exterior of said base, said outer contact member including an arcing electrode section overlapping the other of said end electrodes of said current limiter; said arcing electrode section being formed integrally in said electroconductive material by a U-shaped bend formed along the length of said outer contact member so as to project along the central axis of said current limiter, said U-shaped bend extending transverse to the length along a convex arcuate contour such that the center of the transverse contour is aligned with the center of said other End electrode thereby defining a predetermined spark gap spacing therewith.