US3670129A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Electrical contact members
Assignee: Westinghouse Electric Corp
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Filing: 1970-08-17
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Granted: 1972-06-13
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Expires: 1990-08-17
Abstract
Abstract Electrical make and break contact members for use in a vacuumtype circuit interrupter including a casing forming an evacuated chamber with a pair of separable contacts contained therein and composed of copper (or other similar metal), the contacting surface of each contact having a non-continuous coating of a refractory material, covering the major part of the contact surface and whereby during disengagement of the contacts the welding and high erosion rate of copper caused by an electric arc in a vacuum is minimized by the refractory material coating.
Inventors
- 👤 Sidney J Cherry
- 👤 Albert Bereza
- 👤 Paul O Wayland
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-25 15:48
CPC Classifications
H; H01; H01H; H01H33/00; H01H33/60; H01H33/66; H01H33/664; H01H33/6646; H01H1/00; H01H1/02; H01H1/0203; H01H1/06; H01H33/662; H01H33/66261; H01H2033/66276
Claims Analysis
Total Claims: 8
Claim 1
Independent Claim
130 words
In a vacuum-type circuit interrupter including wall means defining an outer evacuated cylindrical casing, a pair of contacts disposed within the casing and separable from each other whereby to interrupt an electrical circuit and each having a contact surface whereon an electrical arc can form during such interruption, the improvement comprising at least one of the contacts comprises a body of good electrical conducting metal and a discontinuous layer on the contact surface of the contact, said layer being composed of at least one refractory material selected from a group consisting of chromium, iridium, molybdenum, rhenium, tungsten, and base alloys thereof, and the refractory borides, carbides and nitrides of these elements, and which layeR covers from about 60 percent to about 95 percent of the area of the contact surface.
Claim 2
Dependent Claim
130 words
In a vacuum-type circuit interrupter including wall means defining an outer evacuated cylindrical casing, a pair of contacts disposed within the casing and separable from each other whereby to interrupt an electrical circuit and each having a contact surface whereon an electrical arc can form during such interruption, the improvement comprising at least one of the contacts comprises a body of good electrical conducting metal and a discontinuous layer on the contact surface of the contact, said layer being composed of at least one refractory material selected from a group consisting of chromium, iridium, molybdenum, rhenium, tungsten, and base alloys thereof, and the refractory borides, carbides and nitrides of these elements, and which layeR covers from about 60 percent to about 95 percent of the area of the contact surface.
Claim 3
Dependent Claim
29 words
The device of claim 1 wherein the contact body of good electrically conducting metal is selected from a group consisting of copper, silver, and gold, and base alloys thereof.
Claim 4
Dependent Claim
14 words
The device of claim 1 wherein the discontinuous layer is a perforated sheet-like member.
Claim 5
Dependent Claim
25 words
The device of claim 3 wherein each layer includes at least one opening through which the good conducting metal is exposed to the other contact.
Claim 6
Dependent Claim
11 words
The device of claim 1 wherein the discontinuous layer is tungsten.
Claim 7
Dependent Claim
18 words
The device of claim 1 wherein the discontinuous layer has a thickness of up to about 0.03 inch.
Claim 8
Dependent Claim
25 words
The device of claim 1 wherein the discontinuous layer consists of spaced discrete portions between surface portions of the good conducting metal of the contact.
References Cited (Backward Citations)
CA686188A
Cited
US2900476A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1975-06-13 | 1975-12-13 | 1976-06-13 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1979-06-13 | 1979-12-13 | 1980-06-13 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1983-06-13 | 1983-12-13 | 1984-06-13 | $7700.00 | Window Closed / Lapsed |