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US4537743A
Expired / Lapsed
US
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Electrode composition for vacuum switch
Assignee: Mitsubishi Electric Corp
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Filing: 1984-06-25
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Granted: 1985-08-27
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Expires: 2004-06-25
Abstract
Abstract The disclosed electrode composition for a vacuum switch comprises copper, as a principal ingredient, a low melting point metal such as Bi, Pb, In, Li, Sn or any of their alloys, in a content not exceeding 20% by weight, a first additional metal such as Te, Sb, La, Mg or any of their alloys and a refractory metal such as Cr, Fe, Co, Ni, Ti, W or any of their alloys in a content less than 40% by weight.
Inventors
- 👤 Takashi Yamanaka
- 👤 Yasushi Takeya
- 👤 Mitsumasa Yorita
- 👤 Toshiaki Horiuchi
- 👤 Kouichi Inagaki
- 👤 Eizo Naya
- 👤 Michinosuke Demizu
- 👤 Mitsuhiro Okumura
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-02 15:29
CPC Classifications
H; H01; H01H; H01H1/00; H01H1/02; H01H1/0203; Y; Y10; Y10T; Y10T29/00; Y10T29/49; Y10T29/49002; Y10T29/49105; Y10T29/49117; Y10T29/49204; Y10T29/49208; Y10T29/4921; Y10T29/49211; Y10T29/49213; Y10T29/53; Y10T29/5313; Y10T29/532; Y10T29/53248
Claims Analysis
Total Claims: 3
Claim 1
Independent Claim
179 words
An electrode for a vacuum switch, said electrode being produced by subjecting a composition consisting essentially of: (a) not more than 20% by weight of at least one low melting point metal selected from the group consisting of bismuth (Bi), lead (Pb), indium (In), lithium (Li), tin (Sn) and alloys thereof; (b) not more than 10% by weight of a metal capable of forming an alloy with said low melting point metal at a temperature not less than the melting point of said low melting point metal, and being alloyable with copper at a temperature not higher than the melting point of said alloy, selected from the group consisting of tellurium (Te), antimony (Sb), lanthanum (La), magnesium (Mg) and alloys thereof; and (c) the balance being copper (Cu) to a powder metallurgical technique which comprises mixing components (a), (b) and (c) in powder form, molding the resultant mixture into a predetermined electrode shape and sintering the resultant shape in a furnace at a temperature not higher than the melting point of copper in an atmosphere of substantially pure hydrogen.
Claim 2
Dependent Claim
179 words
An electrode for a vacuum switch, said electrode being produced by subjecting a composition consisting essentially of: (a) not more than 20% by weight of at least one low melting point metal selected from the group consisting of bismuth (Bi), lead (Pb), indium (In), lithium (Li), tin (Sn) and alloys thereof; (b) not more than 10% by weight of a metal capable of forming an alloy with said low melting point metal at a temperature not less than the melting point of said low melting point metal, and being alloyable with copper at a temperature not higher than the melting point of said alloy, selected from the group consisting of tellurium (Te), antimony (Sb), lanthanum (La), magnesium (Mg) and alloys thereof; and (c) the balance being copper (Cu) to a powder metallurgical technique which comprises mixing components (a), (b) and (c) in powder form, molding the resultant mixture into a predetermined electrode shape and sintering the resultant shape in a furnace at a temperature not higher than the melting point of copper in an atmosphere of substantially pure hydrogen.
Claim 3
Dependent Claim
46 words
The electrode for a vacuum switch according to claim 1 which additionally contains less than 40% by weight of at least one refractory metal powder selected from the group consisting of chromium (Cr), iron (Fe), cobalt (Co), nickel (Ni), titanium (Ti), tungsten (W) and alloys thereof.
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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) | 1988-08-26 | 1989-02-25 | 1989-08-27 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1992-08-26 | 1993-02-25 | 1993-08-27 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1996-08-26 | 1997-02-25 | 1997-08-27 | $7700.00 | Window Closed / Lapsed |