US3732387A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Key switch
Assignee: Addmaster Corp
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Filing: 1971-10-22
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Granted: 1973-05-08
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Expires: 1991-10-22
Abstract
Abstract A key switch incorporated with a printed circuit board having conductors thereon and a bearing member loosely fitted in a hole formed between adjacent terminal ends of the conductors. A depressible key is slideable in the bearing member and has a generally conical surface engaging an expandable toroidal contact spring member which rests on an outwardly tapering surface of the bearing member. As the key is depressed the conical surface thereof expands the spring member downwardly over the surface of the bearing member and into bridging contact with the conductors.
Inventors
- 👤 W Berry
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-24 14:28
CPC Classifications
H; H01; H01H; H01H1/00; H01H1/12; H01H1/14; H01H1/24; H01H1/242
Claims Analysis
Total Claims: 6
Claim 1
Independent Claim
155 words
A key operated switch comprising a flat support of non-conductive material having a pair of conductors on and extending along the upper surface thereof and having flat upper coplanar contact surfaces spaced from each other, an opening in said support between said conductors, an annular member of non-conductive material extending around said opening and over adjacent portions of said contact surfaces of said conductors, a depressible key member extending through said opening and having a generally conical surface thereon, said key member being movable at right angles to said support, and an expandable toroidal spring contact member of conductive material tensioned over said conical surface and normally located in contact with the upper surface of said annular member, said key member being depressible in said opening whereby to cause said conical surface to expand said contact member radially beyond the upper surface of said annular member and into contact with contact surfaces of said conductors.
Claim 2
Dependent Claim
155 words
A key operated switch comprising a flat support of non-conductive material having a pair of conductors on and extending along the upper surface thereof and having flat upper coplanar contact surfaces spaced from each other, an opening in said support between said conductors, an annular member of non-conductive material extending around said opening and over adjacent portions of said contact surfaces of said conductors, a depressible key member extending through said opening and having a generally conical surface thereon, said key member being movable at right angles to said support, and an expandable toroidal spring contact member of conductive material tensioned over said conical surface and normally located in contact with the upper surface of said annular member, said key member being depressible in said opening whereby to cause said conical surface to expand said contact member radially beyond the upper surface of said annular member and into contact with contact surfaces of said conductors.
Claim 3
Dependent Claim
26 words
A key operated switch according to claim 1 wherein said upper surface of said annular member tapers outwardly towards said conductors to a substantially sharp edge.
Claim 4
Dependent Claim
41 words
A key operated switch according to claim 1 wherein a bearing member fits in said opening in said support and has a flange constituting said annular member extending radially over said conductors, said flange tapering outwardly to a substantially sharp edge.
Claim 5
Dependent Claim
25 words
A key operated switch according to claim 3 wherein said key member is arrested during depression thereof against the upper surface of saiD bearing member.
Claim 6
Dependent Claim
32 words
A key operated switch according to claim 2 wherein the plane of said upper surface of said bearing member extends substantially at right angles to the general plane of said conical surface.
References Cited (Backward Citations)
US959435A
Cited
US3206561A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1976-05-07 | 1976-11-06 | 1977-05-08 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-05-07 | 1980-11-06 | 1981-05-08 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-05-07 | 1984-11-06 | 1985-05-08 | $7700.00 | Window Closed / Lapsed |