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US3843929A Expired / Lapsed US ⏱️ 0.0 years remaining

Automatic t.v. shut-off device responsive to absence of sync. signal

Assignee: Philips North America LLC
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Filing: 1970-08-21
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Granted: 1974-10-22
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Expires: 1990-08-21
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Abstract

Abstract Apparatus for automatically turning off any device, as for example a television receiver, upon the discontinuance of a certain signal component for a preselected period of time. The automatic shut-off feature is incorporated into a conventional television receiver without in any way affecting the normal operation of the television receiver until the station to which the set is tuned, leaves the air. When a station leaves the air, this will be sensed as a loss of a signal component, as for example, the synchronizing signal and automatically thereafter there will be energized a timer mechanism which is effective after a preselected period of time to shut off the television set; but, without in any way interfering with a subsequent turning on of the set by a viewer to a selected television broadcast when the station has resumed broadcasting. The invention is particularly useful where television sets are installed in bedrooms and the televiewer falls asleep, allowing the television set to stay on after the television station has ceased broadcasting.

Inventors

  • 👤 L Mayle

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-25 11:34
CPC Classifications
H; H04; H04N; H04N5/00; H04N5/63; H04W; H04W52/00; H04W52/02; H04W52/0209; H04W52/0225; H04W52/0241; Y; Y02; Y02D; Y02D30/00; Y02D30/70

Claims Analysis

Total Claims: 11
Claim 1
Independent Claim 364 words
An apparatus for automatically turning off a television set having an on-off switch, said on-off switch controlling the source of electrical energy for both said television set and said apparatus comprising: manually operable means for moving said switch to the on position; electrical means associated with said switch and energizable for moving said switch to the off position thereof; a capacitor in circuit with said electrical means operable when charged to a predetermined voltage level to cause momentary energization of said electrical means; a charging circuit connected to said capacitor operable to charge said capacitor at a predetermined rate, said charging cicuit being a purely passive circuit connected to a direct current potential difference within the television set; a discharging circuit connected to said capacitor; said charging circuit being under the control of said switch and initiating charging of said capacitor upon movement of said switch to the on position thereof so thaT a predetermined time after movement of said switch to the on position thereof said capacitor will be charged to said predetermined voltage level unless previously discharged via said discharging circuit; said discharging circuit comprising a transistor having the collector-emitter path thereof connected in shunting relation to said capacitor; a tank circuit coupled to the base of said transistor and operable when energized at the resonant frequency thereof to supply signals to the base of said transistor to make said transistor conductive and thereby discharge said capacitor at a rate not less than the rate at which said capacitor is charged by said charging circuit, whereby, when both said charging and said discharging circuits are operating, said capacitor is prevented from charging; said tank circuit being connected to the television set to receive therefrom a signal received by the television set, whereby, when said television set signal ceases, said discharging circuit becomes inoperative allowing said charging circuit to charge said capacitor thus energizing said electrical means so as to turn said television set and said apparatus off; said tank circuit having as the said resonant frequency a frequency equal to n times the frequency of occurrence of synchronizing pulses in the received signal, wherein n is a whole number greater than one.
Claim 2
Independent Claim 364 words
An apparatus for automatically turning off a television set having an on-off switch, said on-off switch controlling the source of electrical energy for both said television set and said apparatus comprising: manually operable means for moving said switch to the on position; electrical means associated with said switch and energizable for moving said switch to the off position thereof; a capacitor in circuit with said electrical means operable when charged to a predetermined voltage level to cause momentary energization of said electrical means; a charging circuit connected to said capacitor operable to charge said capacitor at a predetermined rate, said charging cicuit being a purely passive circuit connected to a direct current potential difference within the television set; a discharging circuit connected to said capacitor; said charging circuit being under the control of said switch and initiating charging of said capacitor upon movement of said switch to the on position thereof so thaT a predetermined time after movement of said switch to the on position thereof said capacitor will be charged to said predetermined voltage level unless previously discharged via said discharging circuit; said discharging circuit comprising a transistor having the collector-emitter path thereof connected in shunting relation to said capacitor; a tank circuit coupled to the base of said transistor and operable when energized at the resonant frequency thereof to supply signals to the base of said transistor to make said transistor conductive and thereby discharge said capacitor at a rate not less than the rate at which said capacitor is charged by said charging circuit, whereby, when both said charging and said discharging circuits are operating, said capacitor is prevented from charging; said tank circuit being connected to the television set to receive therefrom a signal received by the television set, whereby, when said television set signal ceases, said discharging circuit becomes inoperative allowing said charging circuit to charge said capacitor thus energizing said electrical means so as to turn said television set and said apparatus off; said tank circuit having as the said resonant frequency a frequency equal to n times the frequency of occurrence of synchronizing pulses in the received signal, wherein n is a whole number greater than one.
Claim 3
Dependent Claim 26 words
The apparatus of claim 1 wherein said charging circuit is a purely resistive network connecting said capacitor across a direct current potential within said television set.
Claim 4
Dependent Claim 29 words
An apparatus according to claim 1 which includes a first component in the circuit connecting said capacitor with said electrical means which is nonconductive below said predetermined voltage level.
Claim 5
Dependent Claim 65 words
An apparatus according to claim 3 which includes a normally nonconductive second component in the energizing circuit for said electrical means, said second component having a gate responsive to a voltage signal to become conductive thereby to effect energization of said electrical means, said gate being connected to receive a signal from said first component when the latter becomes conductive at said predetermined voltage level.
Claim 6
Dependent Claim 15 words
An apparatus according to claim 3 in which said first component is a neon bulb.
Claim 7
Dependent Claim 14 words
An apparatus according to claim 3 in which said first component is a diode.
Claim 8
Dependent Claim 16 words
An apparatus according to claim 6 in which said first diode is a four layer diode.
Claim 9
Dependent Claim 31 words
An apparatus according to claim 1 in which said switch has a plurality of on positions into which it is movable in succession prior to moving to the off position thereof.
Claim 10
Independent Claim 328 words
An apparatus for automatically turning off a television set having an on-off switch said on-off switch controlling the source of electrical energy for both said television set and said apparatus; manually operable means for moving said switch to the on position, electrical means associated with said switch and energizable for moving said switch to the off position thereof, a capacitor in circuit with said electrical means operable when charged to a predetermined voltage level to cause momentary energization of said electrical means, a charging circuit connected to said capacitor operable to charge said capacitor at a predetermined rate, a discharging circuit connected to said capacitor, said charging circuit being under the control of said switch and initiating charging of said capacitor upon movement of said switch to the on position thereof so that a predetermined time after movement of said switch to the on position thereof said capacitor will be charged to said predetermined voltage level unless previously discharged via said discharging circuit, said discharging circuit comprising a transistor having the collector-emitter path thereof connected in shunting relation to said capacitor, a tank circuit coupled to the base of said transistor and operable when energized at the resonant frequency thereof to supply signals to the base of said transistor to make said transIstor conductive and thereby discharge said capacitor at a rate not less than the rate at which said capacitor is charged by said charging circuit, said tank circuit being connected to the television set to receive therefrom a signal received by the television set whereby when said television set signal ceases, said discharging circuit becomes inoperative allowing said charging circuit to charge said capacitor thus energizing said electrical means so as to turn said television set and said apparatus off, and said tank circuit having as the said resonant frequency a frequency equal to n times the frequency of occurrence of synchronizing pulses in the received signal, where n is a whole number greater than one.
Claim 11
Independent Claim 328 words
An apparatus for automatically turning off a television set having an on-off switch said on-off switch controlling the source of electrical energy for both said television set and said apparatus; manually operable means for moving said switch to the on position, electrical means associated with said switch and energizable for moving said switch to the off position thereof, a capacitor in circuit with said electrical means operable when charged to a predetermined voltage level to cause momentary energization of said electrical means, a charging circuit connected to said capacitor operable to charge said capacitor at a predetermined rate, a discharging circuit connected to said capacitor, said charging circuit being under the control of said switch and initiating charging of said capacitor upon movement of said switch to the on position thereof so that a predetermined time after movement of said switch to the on position thereof said capacitor will be charged to said predetermined voltage level unless previously discharged via said discharging circuit, said discharging circuit comprising a transistor having the collector-emitter path thereof connected in shunting relation to said capacitor, a tank circuit coupled to the base of said transistor and operable when energized at the resonant frequency thereof to supply signals to the base of said transistor to make said transIstor conductive and thereby discharge said capacitor at a rate not less than the rate at which said capacitor is charged by said charging circuit, said tank circuit being connected to the television set to receive therefrom a signal received by the television set whereby when said television set signal ceases, said discharging circuit becomes inoperative allowing said charging circuit to charge said capacitor thus energizing said electrical means so as to turn said television set and said apparatus off, and said tank circuit having as the said resonant frequency a frequency equal to n times the frequency of occurrence of synchronizing pulses in the received signal, where n is a whole number greater than one.

References Cited (Backward Citations)

US2923862A Cited
US3172041A Cited
US3378775A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1977-10-21 1978-04-22 1978-10-22 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1981-10-21 1982-04-22 1982-10-22 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1985-10-21 1986-04-22 1986-10-22 $7700.00 Window Closed / Lapsed

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