US4739439A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Overvoltage arrester
Assignee: Siemens AG
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Filing: 1987-04-15
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Granted: 1988-04-19
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Expires: 2007-04-15
Abstract
Abstract An overvoltage arrester for handling high surge currents including a pair of electrodes one of which includes a blind bore into which the second electrode projects, thereby providing at least one discharge gap between the two electrodes. The arrester of the present invention has a long useful life and a high surge current carrying capability.
Inventors
- 👤 Juergen Boy
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-28 13:42
CPC Classifications
H; H01; H01T; H01T4/00; H01T1/00; H01T1/24; H01C; H01C7/00; H01C7/10; H01C7/12; H01T4/10; H01T4/12
Claims Analysis
Total Claims: 11
Claim 1
Independent Claim
92 words
An overvoltage arrester comprising: a hollow cylindrical insulator, a pair of electrodes secured to said insulator and providing a vacuum-tight space in the interior of said insulator, one of said electrode extending into said insulator and providing a low deposition space to said insulator, a starting aid secured only to the other of said electrodes and electrically connected thereto, said starting aid extending into said low deposition space, said one electrode including a bore into which said other electrode projects, and said electrodes being shaped to provide a discharge gap between them.
Claim 2
Dependent Claim
92 words
An overvoltage arrester comprising: a hollow cylindrical insulator, a pair of electrodes secured to said insulator and providing a vacuum-tight space in the interior of said insulator, one of said electrode extending into said insulator and providing a low deposition space to said insulator, a starting aid secured only to the other of said electrodes and electrically connected thereto, said starting aid extending into said low deposition space, said one electrode including a bore into which said other electrode projects, and said electrodes being shaped to provide a discharge gap between them.
Claim 3
Dependent Claim
26 words
An overvoltage arrester according to claim 1 in which at least one of said electrodes is covered with a metallic activator layer at said discharge gap.
Claim 4
Dependent Claim
51 words
An overvoltage arrester according to claim 2 wherein the electrodes are secured to said insulator by hard soldering and wherein said activator layer is a fused on layer of aluminum and a metal spread therein which forms an eutectic with aluminum and which has a melting point below the soldering temperature.
Claim 5
Dependent Claim
15 words
An overvoltage arrester according to claim 2 wherein said activator layer is composed of silver.
Claim 6
Dependent Claim
17 words
An overvoltage arrester according to claim 3 wherein said metal is Ag, Cu, Si, Sn, or Cr.
Claim 7
Dependent Claim
20 words
An overvoltage arrester according to claim 3 wherein said activator contains from about 10% to about 40% by weight aluminum.
Claim 8
Dependent Claim
19 words
An overvoltage arrester according to claim 1 which includes at least one graphite starting strip as a starting aid.
Claim 9
Dependent Claim
37 words
An overvoltage arrester according to claim 1 wherein the shortest path from said starting aid along said insulator is at least as long as the smallest spacing between said electrodes in the region of said discharge gap.
Claim 10
Dependent Claim
27 words
An overvoltage arrester according to claim 1 wherein the inside diameter of said insulator is about 1 mm greater than the outside diameter of said one electrode.
Claim 11
Dependent Claim
26 words
An overvoltage arrester according to claim 1 wherein the interior of said arrester contains a mixture of argon and hydrogen containing between 5 and 20% hydrogen.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1991-04-19 | 1991-10-19 | 1992-04-19 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1995-04-19 | 1995-10-19 | 1996-04-19 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1999-04-19 | 1999-10-19 | 2000-04-19 | $7700.00 | Window Closed / Lapsed |