Patent US4320440A successfully refreshed from Google Patents.
US4320440A
Expired / Lapsed
US
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Connect switch
Assignee: FLOWIL INTERNATIONAL (HOLDING) BV
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Filing: 1979-03-19
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Granted: 1982-03-16
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Expires: 1999-03-19
Abstract
Abstract A photoflash unit having a plurality of high voltage type flashlamps mounted in a planar array on a printed circuit board containing circuitry for sequentially igniting the flashlamps in response to successive high voltage firing pulses applied thereto. The circuitry includes a plurality of solid state switches capable of being easily activated by radiant energy generated during flashing of lamps located adjacent to respective switches. Initially, the switches have a high resistance, and after being activated by radiation, they undergo chemical conversion to a conductive state. The switches are prepared from compositions which include a comparatively large proportion of nonconductive inert particulate solids to improve switch functioning.
Inventors
- 👤 Boyd G. Brower
- 👤 John W. Shaffer
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-05 20:01
CPC Classifications
G; G03; G03B; G03B15/00; G03B15/02; G03B15/03; G03B15/04; G03B15/0452; G03B15/0457; H; H05; H05K; H05K1/00; H05K1/02; H05K1/0286; H05K1/0293; H05K2201/00; H05K2201/01; H05K2201/0104; H05K2201/0112; H05K2203/00; H05K2203/17; H05K2203/173
Claims Analysis
Total Claims: 11
Claim 1
Independent Claim
61 words
A radiation switch for a photoflash unit comprising an admixture of material having a dried composition by weight of 34-74% silver carbonate and/or silver oxide, 25-65% of electrically non-conductive inert particulate solids, and 0.5-5% binder, said nonconductive particulate solids including a sodium-containing material, the proportion of said sodium-containing material being not more than 10% by weight of said total dried composition.
Claim 2
Dependent Claim
61 words
A radiation switch for a photoflash unit comprising an admixture of material having a dried composition by weight of 34-74% silver carbonate and/or silver oxide, 25-65% of electrically non-conductive inert particulate solids, and 0.5-5% binder, said nonconductive particulate solids including a sodium-containing material, the proportion of said sodium-containing material being not more than 10% by weight of said total dried composition.
Claim 3
Dependent Claim
13 words
The switch composition of claim 1 wherein said sodium-containing material comprises glass beads.
Claim 4
Dependent Claim
37 words
The switch composition of claim 2 wherein said nonconductive particulate solids include said glass beads and one or more members selected from the group consisting of titanium dioxide, aluminum oxide, aluminum phosphate, barium sulfate, and silicon dioxide.
Claim 5
Dependent Claim
18 words
The switch composition of claim 3 wherein said nonconductive particulate solids consist of titanium dioxide and glass beads.
Claim 6
Dependent Claim
33 words
The switch composition of claim 1 wherein said nonconductive particulate solids are one or more members selected from the group consisting of titanium dioxide, aluminum oxide, aluminum phosphate, barium sulfate, and silicon dioxide.
Claim 7
Dependent Claim
121 words
In a multilamp photoflash unit comprising a pair of flashlamps, an electrical circuit into which said lamps are arranged to fire individually and in sequence, and a solid state radiation switch located external of the lamps and forming part of said electrical circuit, said switch being located adjacent one of said flashlamps to receive radiant energy emitted by that flashlamp, the improvement wherein said radiation switch comprises an admixture of material having a dried composition by weight of 34-74% of silver carbonate and/or silver oxide, 25-65% of electrically nonconductive inert particulate solids, and 0.5-5% binder, said nonconductive particulate solids including a sodium-containing material, the proportion of said sodium-containing material being not more than 10% by weight of said total dried composition.
Claim 8
Dependent Claim
121 words
In a multilamp photoflash unit comprising a pair of flashlamps, an electrical circuit into which said lamps are arranged to fire individually and in sequence, and a solid state radiation switch located external of the lamps and forming part of said electrical circuit, said switch being located adjacent one of said flashlamps to receive radiant energy emitted by that flashlamp, the improvement wherein said radiation switch comprises an admixture of material having a dried composition by weight of 34-74% of silver carbonate and/or silver oxide, 25-65% of electrically nonconductive inert particulate solids, and 0.5-5% binder, said nonconductive particulate solids including a sodium-containing material, the proportion of said sodium-containing material being not more than 10% by weight of said total dried composition.
Claim 9
Dependent Claim
28 words
The photoflash unit of claim 6 wherein said radiation switch comprises a mass of said material interconnected to a pair of spaced-apart electrical terminals in the electrical circuit.
Claim 10
Dependent Claim
33 words
The photoflash unit of claim 7 wherein said nonconductive particulate solids are one or more members selected from the group consisting of titanium dioxide, aluminum oxide, aluminum phosphate, barium sulfate, and silicon dioxide.
Claim 11
Dependent Claim
54 words
The photoflash unit of claim 7 wherein said nonconductive particulate solids include glass beads and one or more members selected from the group consisting of titanium dioxide, aluminum oxide, aluminum phosphate, barium sulfate, and silicon dioxide, the proportion of said glass beads being not more than 10% by weight of said total dried composition.
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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) | 1985-03-15 | 1985-09-14 | 1986-03-16 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1989-03-15 | 1989-09-14 | 1990-03-16 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1993-03-15 | 1993-09-14 | 1994-03-16 | $7700.00 | Window Closed / Lapsed |