US3881061A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Signal discriminator of an automatic telephone answering apparatus
Assignee: Pioneer Corp
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Filing: 1973-01-24
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Granted: 1975-04-29
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Expires: 1993-01-24
Abstract
Abstract A signal discriminator for use with an automatic telephone answering apparatus wherein an incoming message from a caller is discriminated from other signals, such as dial tones, busy tones or other noise. The apparatus is continuously operated to record the incoming message as long as the message arrives, and is returned to a stand-by state after the incoming message is finished even if other signals are coming from a telephone line.
Inventors
- 👤 Shizuo Ando
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-08 04:58
CPC Classifications
H; H04; H04M; H04M1/00; H04M1/64; H04M1/65; H04M1/654
Claims Analysis
Total Claims: 6
Claim 1
Independent Claim
252 words
A signal discriminator of an automatic telephone answering apparatus, comprising: a. a rectifier circuit means for rectifying an input signal received from a telephone line, b. a first monostable switching circuit means coupled to said rectifier circuit means, said first switching circuit means being triggered from a first, stable state to a second state in response to a pulse or other discernible component of a fluctuating input signal received from said rectifier circuit means, c. first timer circuit means associated with said first monostable switching circuit means said timer circuit means providing a switching signal said switching signal being interrupted for a predetermined period following each triggering of said first monostable circuit means to said second state, d. second switching circuit means responsive to both the output signal from said rectifier circuit means and said switching signal whereby said second switching circuit means is switched to a first state upon receiving either or both of said signals and to a second state upon receiving neither of said signals, and, e. a third monostable switching circuit means for controlling the telephone answering apparatus, said third switching circuit means being responsive to actuation of the said second switching circuit means such that when the latter is in said second state said third switching circuit means is triggered from a first state to a second state, and said third switching circuit means returns to its stable first state after said second switching circuit means has been maintained in its first state from a predetermined period.
Claim 2
Dependent Claim
252 words
A signal discriminator of an automatic telephone answering apparatus, comprising: a. a rectifier circuit means for rectifying an input signal received from a telephone line, b. a first monostable switching circuit means coupled to said rectifier circuit means, said first switching circuit means being triggered from a first, stable state to a second state in response to a pulse or other discernible component of a fluctuating input signal received from said rectifier circuit means, c. first timer circuit means associated with said first monostable switching circuit means said timer circuit means providing a switching signal said switching signal being interrupted for a predetermined period following each triggering of said first monostable circuit means to said second state, d. second switching circuit means responsive to both the output signal from said rectifier circuit means and said switching signal whereby said second switching circuit means is switched to a first state upon receiving either or both of said signals and to a second state upon receiving neither of said signals, and, e. a third monostable switching circuit means for controlling the telephone answering apparatus, said third switching circuit means being responsive to actuation of the said second switching circuit means such that when the latter is in said second state said third switching circuit means is triggered from a first state to a second state, and said third switching circuit means returns to its stable first state after said second switching circuit means has been maintained in its first state from a predetermined period.
Claim 3
Dependent Claim
106 words
A signal discriminator as claimed in claim 1, wherein said predetermined period for which said switching signal is interrupted has a duration of order of 0.25 seconds, whereby upon receipt of incoming signals which are either continuous or intermittent with components of duration greater than 0.25 seconds said third switching circuit means is switched to said first state, to render a telephone answering device inoperative, and upon receipt of intermittent or fluctuating incoming signals having signal components of duration less than 0.25 seconds, said third switching circuit means is switched to said second state, to render the telephone answering apparatus operative to record the incoming signal.
Claim 4
Dependent Claim
84 words
A signal discriminator as claimed in claim 1, wherein said timer circuit means comprises a first series resistorcapacitor time constant circuit connected to a power source, the common point between said resistor and capacitor being connected to said second switching circuit means, said first switching circuit means being connected via a differentiating circuit to the output of thE rectifier circuit means wherein the capacitor of said first time constant circuit means is discharged when said first switching circuit means is in said second state.
Claim 5
Dependent Claim
65 words
A signal discriminator as claimed in claim 1, wherein said third switching means includes a second series resistor-capacitor time constant circuit connected to a power source, wherein when said capacitor is charged said third switching circuit means is in said first state, and wherein second switching circuit means is arranged to discharge the capacitor of said second time constant circuit when in its second state.
Claim 6
Dependent Claim
38 words
A signal discriminator claimed in claim 1, including a noise absorbing circuit means for absorbing low level noises, arranged between the output of said rectifying circuit means and the inputs of said first and second switching circuit means.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1978-04-28 | 1978-10-28 | 1979-04-29 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-04-28 | 1982-10-28 | 1983-04-29 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-04-28 | 1986-10-28 | 1987-04-29 | $7700.00 | Window Closed / Lapsed |