US4243852A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Membrane switch with means for impeding silver migration
Assignee: Oak Industries Inc
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Filing: 1979-04-16
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Granted: 1981-01-06
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Expires: 1999-04-16
Abstract
Abstract A membrane switch has a first silver conductor formed on a flexible membrane and a second silver conductor formed on a substrate, which may also be a flexible membrane. A spacer is positioned between and adhesively secured to the substrate and membrane in such a way that there is an opening in the spacer in register with the first and second conductors. Pressure applied to the membrane moves it toward the substrate through the opening in the spacer to cause electrical contact between the first and second conductors. There are means for impeding migration of the silver between the first and second conductors which essentially consists of orienting the conductors so as to provide the longest possible path between portions thereof.
Inventors
- 👤 Willis A. Larson
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-25 11:00
CPC Classifications
H; H01; H01H; H01H13/00; H01H13/70; H01H13/78; H01H13/785; H01H1/00; H01H1/02; H01H13/702; H01H2201/00; H01H2201/022; H01H2201/024; H01H2201/026; H01H2229/00; H01H2229/024; H01H2229/028; H01H2239/00; H01H2239/03
Claims Analysis
Total Claims: 13
Claim 1
Independent Claim
94 words
In a membrane switch, a substrate, a first silver conductor formed on said substrate, a flexible membrane, a second silver conductor formed on said membrane, a spacer positioned between said substrate and membrane, an opening in said spacer in register with said first and second conductors, said membrane moving toward said substrate through said opening to cause contact between said first and second conductors in response to pressure upon the exterior of said membrane, and means for impeding migration of silver between said first and second conductors by maximizing the silver migration path therebetween.
Claim 2
Dependent Claim
94 words
In a membrane switch, a substrate, a first silver conductor formed on said substrate, a flexible membrane, a second silver conductor formed on said membrane, a spacer positioned between said substrate and membrane, an opening in said spacer in register with said first and second conductors, said membrane moving toward said substrate through said opening to cause contact between said first and second conductors in response to pressure upon the exterior of said membrane, and means for impeding migration of silver between said first and second conductors by maximizing the silver migration path therebetween.
Claim 3
Dependent Claim
16 words
The membrane switch of claim 1 further characterized in that said substrate is a flexible material.
Claim 4
Dependent Claim
19 words
The membrane switch of claim 1 further characterized in that said first and second conductors are generally mutually perpendicular.
Claim 5
Dependent Claim
43 words
The membrane switch of claim 3 further characterized by and including a conductive area formed of a lower conductivity non-migrating material formed on at least one of said first and/or second conductors, said conductive area being generally centrally located relative to said opening.
Claim 6
Dependent Claim
31 words
The membrane switch of claim 4 further characterized by and including conductive areas on both said first and second conductors, with said conductive areas being generally in register, one with another.
Claim 7
Dependent Claim
20 words
The membrane switch of claim 1 further characterized in that said spacer is adhesively secured to said substrate and membrane.
Claim 8
Dependent Claim
38 words
The membrane switch of claim 6 further characterized by and including a recess formed between said substrate and spacer adjacent said opening by elimination of adhesive, to lengthen the path of migration between said first and second conductors.
Claim 9
Dependent Claim
42 words
The membrane switch of claim 6 further characterized by and including recesses formed between said substrate and spacer and membrane and spacer adjacent said opening by elimination of adhesive to lengthen the path of silver migration between said first and second conductors.
Claim 10
Dependent Claim
17 words
The membrane switch of claim 8 further characterized in that said recesses extends circumferentially about said opening.
Claim 11
Dependent Claim
38 words
The membrane switch of claim 6 further characterized by and including a recess formed between said membrane and spacer adjacent said opening by elimination of adhesive, to lengthen the path of migration between said first and second conductors.
Claim 12
Dependent Claim
78 words
In a membrane switch, a substrate, a first silver conductor formed on said substrate, a flexible membrane, a second silver conductor formed on said membrane, a spacer positioned between said substrate and membrane, an opening in said spacer in register with said first and second conductors, said first and second conductors being so oriented, one to another in the area of an opening, as to provide the longest path between portions thereof, thereby impeding migration of silver therebetween.
Claim 13
Dependent Claim
78 words
In a membrane switch, a substrate, a first silver conductor formed on said substrate, a flexible membrane, a second silver conductor formed on said membrane, a spacer positioned between said substrate and membrane, an opening in said spacer in register with said first and second conductors, said first and second conductors being so oriented, one to another in the area of an opening, as to provide the longest path between portions thereof, thereby impeding migration of silver therebetween.
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) | 1984-01-06 | 1984-07-07 | 1985-01-06 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1988-01-06 | 1988-07-07 | 1989-01-06 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1992-01-06 | 1992-07-07 | 1993-01-06 | $7700.00 | Window Closed / Lapsed |