US3743880A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Dual filament readout lamp
Assignee: REFAC Tech DEV CORP
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Filing: 1971-05-06
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Granted: 1973-07-03
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Expires: 1991-05-06
Abstract
Abstract A readout lamp for producing numeric or alpha-numeric displays in which two sets of incandescent filament segments in parallel spaced relationship with each other are employed to produce a double lined number or letter. Failure of one or more filaments will still enable the lamp to produce an intelligible display. The two sets of filaments are slightly displaced vertically from each other to prevent electrical contact without destroying the substantially uniplanar appearance of the display.
Inventors
- 👤 P Demarest
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-27 08:52
CPC Classifications
G; G09; G09F; G09F9/00; G09F9/30; G09F9/302; H; H01; H01K; H01K9/00
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
342 words
A miniature dual filament system numeric or alpha-numeric readout lamp comprising: a sealed envelope; a transparent faceplate for said envelope; a ceramic slab spaced from and beneath said transparent faceplate; a ring sealingly connecting the peripheries of said faceplate and slab; a first plurality of electrically conductive posts secured at one end to said slab and extending above its upper surface towards said transparent faceplate; said first plurality of electrically conductive posts being arranged in a first predetermined pattern; a first set of incandescent filaments secured to the free ends of said first plurality of electrically conductive posts for the passage of current and for selectively producing a first display; a second plurality of electrically conductive posts secured at one end to said slab and extending above its upper surface towards the transparent faceplate arranged in a second predetermined pattern similar to said first predetermined pattern; each of said second plurality of electrically conductive posts being adjacent to one of said first plurality of electrically conductive posts; a second set of incandescent filaments vertically displaced from said first set of filaments a distance sufficient to permit filament cross-over while retaining the substantially uniplanar aspect of the display and secured to the free ends of said second plurality of electrically conductive posts for the passage of current and for selectively producing a second display; said second set of filaments being disposed substantially parallel to said first set of filaments so that said second display is substantially the same as said first display; electrically connecting means on the surface of said slab opposite said filaments in contact with said posts, said means including separate connections for each free end so that the display produced by the first set of incandescent filaments is independent of the display produced by the second set of incandescent filaments; a plurality of lead-in conductors for said connecting means for connecting the filaments to an external source of power; and a block of dielectric material having filament receiving bores therein, and means to support the block within the sealed envelope.
Claim 2
Dependent Claim
342 words
A miniature dual filament system numeric or alpha-numeric readout lamp comprising: a sealed envelope; a transparent faceplate for said envelope; a ceramic slab spaced from and beneath said transparent faceplate; a ring sealingly connecting the peripheries of said faceplate and slab; a first plurality of electrically conductive posts secured at one end to said slab and extending above its upper surface towards said transparent faceplate; said first plurality of electrically conductive posts being arranged in a first predetermined pattern; a first set of incandescent filaments secured to the free ends of said first plurality of electrically conductive posts for the passage of current and for selectively producing a first display; a second plurality of electrically conductive posts secured at one end to said slab and extending above its upper surface towards the transparent faceplate arranged in a second predetermined pattern similar to said first predetermined pattern; each of said second plurality of electrically conductive posts being adjacent to one of said first plurality of electrically conductive posts; a second set of incandescent filaments vertically displaced from said first set of filaments a distance sufficient to permit filament cross-over while retaining the substantially uniplanar aspect of the display and secured to the free ends of said second plurality of electrically conductive posts for the passage of current and for selectively producing a second display; said second set of filaments being disposed substantially parallel to said first set of filaments so that said second display is substantially the same as said first display; electrically connecting means on the surface of said slab opposite said filaments in contact with said posts, said means including separate connections for each free end so that the display produced by the first set of incandescent filaments is independent of the display produced by the second set of incandescent filaments; a plurality of lead-in conductors for said connecting means for connecting the filaments to an external source of power; and a block of dielectric material having filament receiving bores therein, and means to support the block within the sealed envelope.
References Cited (Backward Citations)
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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) | 1976-07-02 | 1977-01-01 | 1977-07-03 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-07-02 | 1981-01-01 | 1981-07-03 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-07-02 | 1985-01-01 | 1985-07-03 | $7700.00 | Window Closed / Lapsed |