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US4457780A Expired / Lapsed US ⏱️ 0.0 years remaining

Electric contact materials

Assignee: Sumitomo Electric Industries Ltd
•
Filing: 1982-04-12
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Granted: 1984-07-03
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Expires: 2002-04-12
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Abstract

Abstract The invention relates to electric contact materials for use in switches, such as moulded circuit breakers, air circuit breakers, magnetic switches, etc. The electric contact materials comprise 5-60 weight % iron group metals, 1-11 weight % graphite, 5-70 weight % refractory materials, and the residual part consisting of silver, said refractory materials being held in the state of dispersion in the iron group metals and/or silver, thereby providing welding resistance, wear resistance, and insulation resistance as well as high practical utility of low temperature rise.

Inventors

  • 👤 Mitsuo Osada
  • 👤 Nobuhito Kuroishi
  • 👤 Yoshinari Amano
  • 👤 Akira Fukui

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-28 15:58
CPC Classifications
H; H01; H01H; H01H1/00; H01H1/02; H01H1/021; H01H1/023; H01H1/0233

Claims Analysis

Total Claims: 9
Claim 1
Independent Claim 63 words
Electric contact material comprising 5-60 weight % of at least one iron group metal, 1-11 weight % of graphite, 5-70 weight % of refractory material, and the residual part consisting essentially of silver, said silver being present in the material in an amount of at least 10 weight %, wherein the refractory material is dispersed in the iron group metal and/or the silver.
Claim 2
Dependent Claim 63 words
Electric contact material comprising 5-60 weight % of at least one iron group metal, 1-11 weight % of graphite, 5-70 weight % of refractory material, and the residual part consisting essentially of silver, said silver being present in the material in an amount of at least 10 weight %, wherein the refractory material is dispersed in the iron group metal and/or the silver.
Claim 3
Dependent Claim 38 words
Electric contact material as defined in claim 1, wherein the refractory material is at least one member selected from refractory metals of groups IVa, Va and VIa of the periodic table, and carbides, nitrides, borides and silicides thereof.
Claim 4
Dependent Claim 36 words
Electric contact material as defined in claim 1, wherein the refractory material comprises a refractory metal of group IVa, Va or VIa and a carbide thereof, the amount of said refractory metal being 0.1-5 weight %.
Claim 5
Dependent Claim 36 words
Electric contact material as defined in claim 1, wherein the refractory material comprises a boride and a silicide of a group IVa, Va or VIa refractory metal, the amount of said silicide being 0.1-30 weight %.
Claim 6
Dependent Claim 35 words
Electric contact material as defined in claim 1, wherein the refractory material comprises a group IVa, Va or VIa refractory metal and a nitride thereof, the amount of said refractory metal being 0.1-30 weight %.
Claim 7
Dependent Claim 30 words
Electric contact material as defined in claim 1, wherein the refractory material comprises 5-50 weight % of a nitride of a group IVa, Va, VIa, VIIa or VIIIa refractory metal.
Claim 8
Dependent Claim 47 words
Electric contact material as defined in claim 1, wherein the refractory material comprises a carbide of a group IVa, Va or VIa refractory metal and a nitride of a group IVa, Va, VIa, VIIa or VIIIa refractory metal, the amount of said nitride being 0.1-30 weight %.
Claim 9
Dependent Claim 69 words
A process for producing the electric contact material as defined in claim 1, which comprises mixing, all in powder form, 5-60 weight % of at least one iron group metal, 1-11 weight % of graphite, 5-70 weight % of refractory material, and silver; pressing the resultant mixture to obtain a compact; and sintering the compact at a temperature above 1000° C. in a reducing gas atmosphere for 1-5 hours.

References Cited (Backward Citations)

US2180956A Cited
US2234969A Cited
US2319240A Cited
JPS5195271A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1987-07-03 1988-01-02 1988-07-03 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1991-07-03 1992-01-02 1992-07-03 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1995-07-03 1996-01-02 1996-07-03 $7700.00 Window Closed / Lapsed

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