Patent US3686445A successfully refreshed from Google Patents.
US3686445A
Expired / Lapsed
US
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Timing signal generators
Assignee: Individual
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Filing: 1971-03-01
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Granted: 1972-08-22
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Expires: 1991-03-01
Abstract
Abstract A timing circuit for use in converting from push-button derived signals to dial-type impulse trains, in which the different intervals required in the conversion are obtained by dividingdown signals from a master oscillator operating at 20 kH. The timing circuit uses MOS integrated circuits and comprises three ''''twisted ring'''' dividing circuits of different division ratios, different interval timing signals being derived from coincident output signals from two of these dividing circuits and from all three of the dividing circuits respectively.
Inventors
- 👤 Bernard Sydney Barnaby
- 👤 Graham Webb
- 👤 Robert Andrew Stevenson
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-25 19:43
CPC Classifications
H; H04; H04Q; H04Q1/00; H04Q1/18; H04Q1/30; H04Q1/50; H04M; H04M1/00; H04M1/26; H04M1/30; H04M1/31; H04M1/312
Claims Analysis
Total Claims: 10
Claim 1
Independent Claim
105 words
An electric impulse transmitter for a push-button telephone instrument including electric storage means for storing digit values selected by operation of respective push-buttons of the instrument, wherein means for timing impulse trains representative of the digit values stored in said storage means comprises a pulse generator, at least two frequency dividing circuits each responsive to a different number of pulses from the output of said pulse generator periodically to provide a respective output pulse, and gating means to derive timing signals for timing the mark and space intervals of said impulse trains in response to coincident output pulses from two of said frequency dividing circuits.
Claim 2
Dependent Claim
105 words
An electric impulse transmitter for a push-button telephone instrument including electric storage means for storing digit values selected by operation of respective push-buttons of the instrument, wherein means for timing impulse trains representative of the digit values stored in said storage means comprises a pulse generator, at least two frequency dividing circuits each responsive to a different number of pulses from the output of said pulse generator periodically to provide a respective output pulse, and gating means to derive timing signals for timing the mark and space intervals of said impulse trains in response to coincident output pulses from two of said frequency dividing circuits.
Claim 3
Dependent Claim
131 words
An electric impulse transmitter for a push-button telephone instrument including electric storage means for storing digit values selected by operation of respective push-buttons of the instrument, wherein means for timing impulse trains representative of the electric signals stored in said storage means comprises a pulse generator, three frequency dividing circuits each responsive to a different number of pulses from the output of said pulse generator to provide a respective output pulse, gating means to derive timing signals for timing the mark and space intervals of said impulse trains in response to coincident output pulses from two of said frequency dividing circuits, gating means to derive timing signals for timing the interdigit pause intervals between said impulse trains in response to coincident output pulses from all three of said frequency dividing circuits.
Claim 4
Dependent Claim
131 words
An electric impulse transmitter for a push-button telephone instrument including electric storage means for storing digit values selected by operation of respective push-buttons of the instrument, wherein means for timing impulse trains representative of the electric signals stored in said storage means comprises a pulse generator, three frequency dividing circuits each responsive to a different number of pulses from the output of said pulse generator to provide a respective output pulse, gating means to derive timing signals for timing the mark and space intervals of said impulse trains in response to coincident output pulses from two of said frequency dividing circuits, gating means to derive timing signals for timing the interdigit pause intervals between said impulse trains in response to coincident output pulses from all three of said frequency dividing circuits.
Claim 5
Dependent Claim
40 words
An electric impulse transmitter in accordance with claim 1 wherein each of the frequency dividing circuits comprises a respective multistage shift register which is made cyclic in operation by a feedback connection from its output stage to its input stage.
Claim 6
Dependent Claim
17 words
An electric impulse transmitter in accordance with claim 3 wherein the feedback connection includes an inverting stage.
Claim 7
Dependent Claim
27 words
An electric impulse transmitter in accordance with claim 1 wherein the means for timing impulse trains is formed substantially as a single-chip integrated circuit utilizing metal-oxide-semiconductor transistors.
Claim 8
Dependent Claim
145 words
In a push-button telephone instrument for connection to conventional dialling-impulse type exchange equipment, an electric impulse transmitter comprising a set of push buttons, electric storage means for storing digit values selected by operation of respective ones of said push-buttons, switching circuit means to generate trains of impulses in dependence upon the digit values stored in said storage means, and interval timing means comprising a pulse generator, at least two frequency dividing circuits each responsive to a different number of pulses from the output of said pulse generator periodically to provide a respective output pulse, gating means responsive to coincident output signals from two of said frequency dividing circuits to time the generation by said switching circuit means of said impulses, a pair of line terminals for the instrument, and means responsive to said impulses selectively to establish a low impedance path between said line terminals.
Claim 9
Dependent Claim
145 words
In a push-button telephone instrument for connection to conventional dialling-impulse type exchange equipment, an electric impulse transmitter comprising a set of push buttons, electric storage means for storing digit values selected by operation of respective ones of said push-buttons, switching circuit means to generate trains of impulses in dependence upon the digit values stored in said storage means, and interval timing means comprising a pulse generator, at least two frequency dividing circuits each responsive to a different number of pulses from the output of said pulse generator periodically to provide a respective output pulse, gating means responsive to coincident output signals from two of said frequency dividing circuits to time the generation by said switching circuit means of said impulses, a pair of line terminals for the instrument, and means responsive to said impulses selectively to establish a low impedance path between said line terminals.
Claim 10
Dependent Claim
47 words
An electric impulse transmitter in accordance with claim 6 wherein the interval timing means comprises three frequency dividing circuits, and there are provided gating means responsive to coincident output signals from all three of said frequency dividing circuits to time interdigit pauses between respective trains of impulses.
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) | 1975-08-22 | 1976-02-21 | 1976-08-22 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1979-08-22 | 1980-02-21 | 1980-08-22 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1983-08-22 | 1984-02-21 | 1984-08-22 | $7700.00 | Window Closed / Lapsed |