Patent US3725745A successfully refreshed from Google Patents.
US3725745A
Expired / Lapsed
US
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Voltage surge protection device for electric meters
Assignee: ABB Inc USA
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Filing: 1971-09-23
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Granted: 1973-04-03
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Expires: 1991-09-23
Abstract
Abstract A voltage surge protection device having a combined current limiter and arc discharge arrangement extending through the enclosure of an electric meter includes an improved outer contact strip with an integrally formed arcing electrode section. A Ushaped bend in the contact strip defines the arcing electrode section and is aligned with the central axis of a cooperating arcing electrode end of the current limiter. A predetermined spark gap spacing is formed between the electrodes for controlling arc discharges within a localized path. The current limiter includes a valve block having a heat shrinkable insulating cover for compressively reinforcing the body of the valve block against mechanical destruction and preventing arcing flashovers.
Inventors
- 👤 W Zisa
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-30 20:27
CPC Classifications
G; G01; G01R; G01R1/00; G01R1/36; H; H01; H01T; H01T1/00; H01T1/16; H01T4/00; H01T4/08
Claims Analysis
Total Claims: 5
Claim 1
Independent Claim
240 words
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.
Claim 2
Dependent Claim
240 words
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.
Claim 3
Dependent Claim
41 words
The electrode meter as claimed in claim 1 wherein; said hole opening is terminated by an aperture extending to the exterior of said base, said aperture receiving said arcing electrode section so as to form a chamber surrounding said spark gap.
Claim 4
Dependent Claim
89 words
The electric meter as claimed in claim 2 wherein said arcing electrode section is formed intermediate first and second ends of said outer contact member, said first end being disposed toward the periphery of said insulating base and including a ground connector section and said second end terminating in a tip portion extending across the edge of said aperture for resiliently engaging said insulating base so as to maintain said arcing electrode section in a fixed spark gap spaced relationship with said other end electrode of said current limiter.
Claim 5
Dependent Claim
35 words
The electric meter of claim 1 wherein said current limiter includes a valve block having a peripheral side surface and an insulating cover made of a heat shrinkable tubing material compressibly binding said side surface.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1976-04-02 | 1976-10-02 | 1977-04-03 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-04-02 | 1980-10-02 | 1981-04-03 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-04-02 | 1984-10-02 | 1985-04-03 | $7700.00 | Window Closed / Lapsed |