US3728489A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Telephone answering apparatus
Assignee: BTI Ltd
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Filing: 1972-05-23
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Granted: 1973-04-17
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Expires: 1992-05-23
Abstract
Abstract A telephone answering system with recording and playback modes. The system is coupled to a telephone line and is electrically independent of the telephone set with which it operates. The system is actuated by a ring signal on a telephone line and includes a circuit which is responsive to the ring signal to interrupt and seize the phone line for a short interval. Thereafter a hold circuit coupled to the line feeds its output to a pulse noise rejection circuit which determines if a true call is on the line and if so triggers a control circuit which causes a prerecorded message on a first tape recorder to be transmitted to the caller. Afterward, the system will couple any spoken message from the calling party to a second tape recorder in response to the prerecorded message. The recorded messages on the second tape recorder from the calling party then may be played back later at will.
Inventors
- 👤 W Beacham
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-26 17:41
CPC Classifications
H; H04; H04M; H04M1/00; H04M1/64; H04M1/65; H04M1/654
Claims Analysis
Total Claims: 23
Claim 1
Independent Claim
398 words
A telephone answering system independently operable with respect to a telephone receiving and transmitting set which is to be answered and said telephone set remains in an ''''on-hook'''' state throughout operation of said system, comprising, in combination: circuit means connected to a telephone line pair coupled to said telephone set for sensing a ringing signal thereon, seizing and maintaining seizure of said telephone line pair by coupling a predetermined impedance across said line pair, and providing an output signal of a first type when said telephone line pair is unseized and an output signal of a second type when said telephone line is seized; pulse noise rejection circuit means for preventing false initiation of operation of the system coupled to said circuit means and providing a first binary output signal and a delayed binary output signal in response to said output signal of said second type from said circuit means; a first bistable control circuit for controlling message transmitting means, coupled to said pulse noise rejection circuit means, and responsive to said first binary signal and said delayed binary output signal, becoming operable to switch to a first operating state when said binary output signals from said pulse noise rejection circuit are coincident in time to provide first energizing signal; message transmitting means coupled to said first bistable control circuit, being rendered operative in response to said first energizing signal to couple a prerecorded message to said telephone line, and said message transmitting means becoming automatically inoperative after a predetermined elapsed time and generating a first control signal at said time, said first control signal being coupled back to said first bistable control circuit whereupon said first bistable control circuit switches to a second operating state; a second bistable control circuit for controlling message receiving means, coupled to said message transmitting means and being responsive to said first control signal generated thereby to switch to a first operating state and provide a second and third energizing signal, said second bistable control circuit additionally being coupled to said pulse noise rejection circuit means and being responsive to said first binary output signal to switch to a second operating state; and message receiving means having input means coupled to said telephone line and coupled to said second bistable control circuit, being rendered operative in response to said second energizing signal to receive a message transmitted thereto over said telephone lines.
Claim 2
Dependent Claim
398 words
A telephone answering system independently operable with respect to a telephone receiving and transmitting set which is to be answered and said telephone set remains in an ''''on-hook'''' state throughout operation of said system, comprising, in combination: circuit means connected to a telephone line pair coupled to said telephone set for sensing a ringing signal thereon, seizing and maintaining seizure of said telephone line pair by coupling a predetermined impedance across said line pair, and providing an output signal of a first type when said telephone line pair is unseized and an output signal of a second type when said telephone line is seized; pulse noise rejection circuit means for preventing false initiation of operation of the system coupled to said circuit means and providing a first binary output signal and a delayed binary output signal in response to said output signal of said second type from said circuit means; a first bistable control circuit for controlling message transmitting means, coupled to said pulse noise rejection circuit means, and responsive to said first binary signal and said delayed binary output signal, becoming operable to switch to a first operating state when said binary output signals from said pulse noise rejection circuit are coincident in time to provide first energizing signal; message transmitting means coupled to said first bistable control circuit, being rendered operative in response to said first energizing signal to couple a prerecorded message to said telephone line, and said message transmitting means becoming automatically inoperative after a predetermined elapsed time and generating a first control signal at said time, said first control signal being coupled back to said first bistable control circuit whereupon said first bistable control circuit switches to a second operating state; a second bistable control circuit for controlling message receiving means, coupled to said message transmitting means and being responsive to said first control signal generated thereby to switch to a first operating state and provide a second and third energizing signal, said second bistable control circuit additionally being coupled to said pulse noise rejection circuit means and being responsive to said first binary output signal to switch to a second operating state; and message receiving means having input means coupled to said telephone line and coupled to said second bistable control circuit, being rendered operative in response to said second energizing signal to receive a message transmitted thereto over said telephone lines.
Claim 3
Dependent Claim
56 words
The apparatus as defined by claim 1 and additionally including a tone pulse generator circuit having output means coupled to said telephone line and coupled to said second bistable control circuit and being responsive to said third energizing signal to translate a tone pulse to said telephone line when said third energizing signal is received therefrom.
Claim 4
Dependent Claim
26 words
The invention as defined by claim 1 wherein said message transmitting means comprises a first recorder means and said message receiving means comprises second recorder means.
Claim 5
Dependent Claim
25 words
The telephone answering system as defined by claim 1 wherein said first and second bistable control circuit, respectively, comprise a first and second flip-flop circuit.
Claim 6
Dependent Claim
85 words
The invention as defined by claim 4 and additionally including controlled power application circuit means coupled to said circuit means and being responsive to said output signal of said second type to connect power to said pulse noise rejection circuit means, said first and second flip-flop circuit, said message transmitting means, and said message receiving means, and including circuit means for becoming inoperative and disconnecting power therefrom when said message transmitting means becomes inoperative coincident in time with said output signal of said first type.
Claim 7
Dependent Claim
57 words
The invention as defined by claim 5 and additionally including means for applying a meSsage to said transmitting means and circuit means for rendering said pulse noise rejection circuit operative to cause said first flop-flop circuit to switch states, thereby energizing said message transmitting means and rendering said controlled power application circuit operative to apply power thereto.
Claim 8
Dependent Claim
143 words
The system as defined by claim 4 when said circuit means comprises: a ring signal detector for sensing a ringing signal applied to said telephone line pair and providing a control signal in the event thereof; and hold circuit means coupled to said telephone line pair and including an impedance substantially equal to the ''''off-hook'''' impedance of a telephone and a normally open voltage controlled switch connected in series across said telephone line pair, control circuit means coupled between ring signal detector and said voltage controlled switch, said control circuit means being responsive to said control signal to close said voltage controlled switch to connect said impedance across said telephone line pair, and means responsive to another telephone line pair operating state coupled to said control circuit means for opening said controlled switch to disconnect said impedance from across said telephone line pair.
Claim 9
Dependent Claim
24 words
The system as defined by claim 7 wherein said control circuit means comprises a flip-flop circuit and said controlled switch comprises a semiconductor device.
Claim 10
Dependent Claim
63 words
The apparatus as defined by claim 4 wherein said pulse noise rejection circuit comprises a digital time delay circuit responsive to said output signal of said second type and including at least one logic inverter circuit including input means responsive to said output signal of said second type to cause said logic inverter to switch output logic states after a predetermined time delay.
Claim 11
Dependent Claim
24 words
The apparatus as defined in claim 9 wherein said input means of said at least one logic inverter circuit includes an R-C charging circuit.
Claim 12
Dependent Claim
42 words
The invention as defined by claim 10 and additionally including a dual input NAND logic gate having one input coupled to said hold circuit and an output coupled to said R-C charging circuit and also to said first and second flip-flop circuit.
Claim 13
Dependent Claim
118 words
The invention as defined by claim 4 wherein said power application circuit means comprises a third flip-flop circuit and normally open voltage controlled switch means coupled to said third flip-flop circuit for being rendered closed thereby and making a complete power circuit path, and additionally including first circuit means coupled to said first recited circuit means for triggering said third flip-flop circuit when said telephone line is seized and said output signal of said second type appears, and second circuit means coupled to said first flip-flop and said pulse noise rejection circuit receiving signals therefrom for resetting said third flip-flop when said message transmitting means is rendered inoperative and said output signal of said first type is present.
Claim 14
Dependent Claim
16 words
The apparatus as defined by claim 12 wherein said voltage controlled switch means comprises a transistor.
Claim 15
Dependent Claim
17 words
The invention as defined by claim 12 wherein said second circuit means comprises a NAND logic gate.
Claim 16
Dependent Claim
170 words
The system as defined by claim 4 wherein said circuit means comprises: a ring signal detector circuit for sensing a ringing signal applied to said telephone line pair, said detector circuit including circuit means responsive to said ringing signal to initially apply said predetermined impedance across said telephone line for a predetermined period of time, wherein said impedance is substantially equal to the impedance of an ''''off-hook'''' telephone set for seizing the telephone line and effectively answering an incoming call, said detector circuit additionally including circuit means for becoming automatically inoperative after said predetermined period of time and uncoupling said impedance from the telephone line; hold circuit means coupled to said telephone line pair providing an output signal oF a first type when said telephone line is unseized and an output signal of a second type when said telephone line is seized and additionally including circuit means applying another impedance substantially equal to the ''''off-hook'''' impedance of a telephone set after said predetermined period of time for retaining line seizure.
Claim 17
Dependent Claim
58 words
The apparatus as defined by claim 15 wherein said hold circuit means comprises normally open switch means and an impedance substantially equal to the impedance of an ''''off-hook'''' telephone set coupled in series across said telephone line, said switch means being operable to be rendered closed when said telephone line is seized by said ring signal detector circuit.
Claim 18
Dependent Claim
15 words
The apparatus as defined by claim 16 wherein said switch means comprises a semiconductor device.
Claim 19
Dependent Claim
27 words
The apparatus as defined in claim 17 wherein said semiconductor device comprises a diode poled to become conductive when a negative voltage appears across said telephone line.
Claim 20
Dependent Claim
112 words
The apparatus as defined by claim 15 wherein said ring signal detector circuit comprises a binary logic circuit having a first logic output state in absence of a ringing signal and being triggered to a second logic output state when a ringing signal is applied to said telephone line pair and additionally including circuit means for reverting back to said first output state after said predetermined time period; normally open voltage controlled switch means coupled to said binary logic circuit, being rendered operatively closed in response to said second logic output state; and said predetermined impedance means substantially being coupled by means of said switch means across said telephone line when closed.
Claim 21
Dependent Claim
16 words
The apparatus as defined by claim 19 wherein said voltage controlled switch means comprises a transistor.
Claim 22
Dependent Claim
226 words
The apparatus as defined by claim 19 wherein said binary logic output circuit includes; a NAND logic gate having first and second inputs; first circuit means coupled to said first input of said NAND gate to provide a binary signal of a first binary logic sense, second circuit means coupled from said telephone line pair to said first input of said NAND gate to provide a binary signal of a second binary logic sense when a ringing signal appears on said telephone line; an R-C charging circuit; a first binary logic inverter circuit coupled to the output of said NAND circuit means of said R-C charging circuit; a second binary logic inverter circuit coupled to the output of said first logic inverter and having an output coupled to said voltage controlled switch means and additionally including circuit means coupling the output of said first logic inverter back to said second input of said NAND gate; said ringing signal changing the logic output state of said NAND logic gate to said first binary logic sense, said first logic sense signal being coupled in sequence to said first and second logic inverter to render said transistor conductive, said R-C charging circuit thereafter charging and after said predetermined time interval causing the input of said first and second logic inverters to change output states and render said transistor non-conductive.
Claim 23
Dependent Claim
76 words
The apparatus as defined in claim 21 wherein said first circuit means comprises a resistor and a capacitor connected in series across a fixed voltage and said capacitor is connected across said first input of said NAND logic gate; and said second circuit means includes a normally non-conductive diode connected across said capacitor and capacitive coupling means coupling said diode to said telephone line pair and becoming conductive when said ringing signal appears on said line.
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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) | 1976-04-16 | 1976-10-16 | 1977-04-17 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-04-16 | 1980-10-16 | 1981-04-17 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-04-16 | 1984-10-16 | 1985-04-17 | $7700.00 | Window Closed / Lapsed |