Patent US3767967A successfully refreshed from Google Patents.
US3767967A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Instant-on circuitry for ac/dc television receivers
Assignee: RCA Licensing Corp
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Filing: 1971-11-24
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Granted: 1973-10-23
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Expires: 1991-11-24
Abstract
Abstract A single pole switching arrangement maintains the filament of the cathode-ray kinescope of a television receiver at full power when the set is turned to an ''''ON'''' condition and connected to an alternating current power source, but operates the filament at half power when the set is turned to its ''''OFF'''' state. When the receiver is connected to a direct current power source, on the other hand, no filament power is used when the single pole arrangement switches the set to its ''''OFF'''' condition, thereby extending the number of viewing hours between direct current battery re-charges, for example. Switching the single pole arrangement to turn the receiver to its ''''ON'''' state when the set is connected to the direct current source once again applies full power to the kinescope filament.
Inventors
- 👤 D Luz
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-31 09:58
CPC Classifications
H; H04; H04N; H04N5/00; H04N5/63; H02; H02M; H02M1/00; H02M1/0003; H02M1/0032; Y; Y02; Y02B; Y02B70/00; Y02B70/10
Claims Analysis
Total Claims: 7
Claim 1
Independent Claim
236 words
In a television receiver, the combination comprising: a cathode-ray kinescope having a heater filament; first means for providing a source of alternating voltage; a full wave rectifier network coupled to said first means and responsive to the alternating voltage provided thereby for developing rectified direct voltages between a pair of output terminals of said network; second means coupling said network terminals between opposite ends of said kinescope filament along a filament coupling path for applying rectified direct voltages to energize said kinescope; a filter capacitor; and third means for switching said capacitor into said filament coupling path to filter the rectified direct voltages coupled for application to said cathode-ray kinescope when it is desired to operate said television receiver from said alternating voltage, and for switching said capacitor out of said coupling path to provide unfiltered rectified direct voltages for application to said cathode-ray kinescope when it is desired to de-energize said television receiver, whereby the value of unfiltered rectified direct voltages applied to said kinescope when said capacitor is switched out of said coupling path is less than the value of filtered rectified direct voltage applied to said kinescope when said capacitor is switched into said coupling path such that said filament operates at a first power from said alternating voltage when said capacitor is switched into said coupling path and operates at substantially half-power when said capacitor is switched out of said coupling path.
Claim 2
Dependent Claim
236 words
In a television receiver, the combination comprising: a cathode-ray kinescope having a heater filament; first means for providing a source of alternating voltage; a full wave rectifier network coupled to said first means and responsive to the alternating voltage provided thereby for developing rectified direct voltages between a pair of output terminals of said network; second means coupling said network terminals between opposite ends of said kinescope filament along a filament coupling path for applying rectified direct voltages to energize said kinescope; a filter capacitor; and third means for switching said capacitor into said filament coupling path to filter the rectified direct voltages coupled for application to said cathode-ray kinescope when it is desired to operate said television receiver from said alternating voltage, and for switching said capacitor out of said coupling path to provide unfiltered rectified direct voltages for application to said cathode-ray kinescope when it is desired to de-energize said television receiver, whereby the value of unfiltered rectified direct voltages applied to said kinescope when said capacitor is switched out of said coupling path is less than the value of filtered rectified direct voltage applied to said kinescope when said capacitor is switched into said coupling path such that said filament operates at a first power from said alternating voltage when said capacitor is switched into said coupling path and operates at substantially half-power when said capacitor is switched out of said coupling path.
Claim 3
Dependent Claim
36 words
The combination of claim 1 wherein said first means includes a transformer having a secondary winding to which said rectifier network is coupled and a primary winding adapted for connection to a source of alternating power.
Claim 4
Dependent Claim
57 words
The combination of claim 2 wherein said rectifier network includes first and second rectifier devices having their anode electrodes interconnected and their cathode electrodes coupled to opposite terminals on said secondary winding, and wherein said second means couples said kinescope filament between an intermediate tap on said secondary winding and to said anode electrodes of said rectifiers.
Claim 5
Dependent Claim
32 words
The combination of claim 3 wherein said third means switches said filter capacitor in circuit between said intermediate tap and said anode electrodes when it is desired to operate said cathode-ray kinescope.
Claim 6
Dependent Claim
190 words
A power supply circuit for the filament of a cathode-ray kinescope comprising: a first transformer winding providing an alternating current voltage and having first, second and third taps; first, second, third and fourth rectifier devices, each having anode and cathode electrodes; direct connections from the cathode electrodes of said first and second devices to said first tap on said transformer winding; direct connections from the cathode electrodes of said third and fourth devices to said second tap on said transformer winding; a direct connection between the anode electrodes of said first and fourth Rectifier devices; a direct connection between the anode electrodes of said second and third rectifier devices; means coupling the filament of said cathode-ray kinescope between the anode electrode of said first rectifier and said third tap on said transformer winding; a filter capacitor; and a single pole switching means which, in a closed position, couples said capacitor between the anode electrode of said second rectifier and said third tap on said secondary winding, and which forms a current coupling path including a portion of said transformer winding between said second rectifier anode and said third winding tap.
Claim 7
Dependent Claim
190 words
A power supply circuit for the filament of a cathode-ray kinescope comprising: a first transformer winding providing an alternating current voltage and having first, second and third taps; first, second, third and fourth rectifier devices, each having anode and cathode electrodes; direct connections from the cathode electrodes of said first and second devices to said first tap on said transformer winding; direct connections from the cathode electrodes of said third and fourth devices to said second tap on said transformer winding; a direct connection between the anode electrodes of said first and fourth Rectifier devices; a direct connection between the anode electrodes of said second and third rectifier devices; means coupling the filament of said cathode-ray kinescope between the anode electrode of said first rectifier and said third tap on said transformer winding; a filter capacitor; and a single pole switching means which, in a closed position, couples said capacitor between the anode electrode of said second rectifier and said third tap on said secondary winding, and which forms a current coupling path including a portion of said transformer winding between said second rectifier anode and said third winding tap.
References Cited (Backward Citations)
US3448335A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1976-10-22 | 1977-04-23 | 1977-10-23 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-10-22 | 1981-04-23 | 1981-10-23 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-10-22 | 1985-04-23 | 1985-10-23 | $7700.00 | Window Closed / Lapsed |