Patent US3591858A successfully refreshed from Google Patents.
US3591858A
Expired / Lapsed
US
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Pulse rate to analog converter
Assignee: Beckman Coulter Inc
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Filing: 1968-05-31
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Granted: 1971-07-06
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Expires: 1988-05-31
Abstract
Abstract A system for providing an analog output signal whose average amplitude is proportional to the frequency of an input signal including a constant pulse width generator responsive to the input signal for providing a series of pulses each of which has a predetermined duration at the same frequency as the input signal and an averaging circuit responsive to the series of pulses for providing an analog signal whose average amplitude is a function of the duty cycle of the constant pulse width generator.
Inventors
- 👤 William R Boyd
- 👤 Robert C Franklin
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-01 09:49
CPC Classifications
G; G01; G01R; G01R23/00; G01R23/02; G01R23/06; G01P; G01P3/00; G01P3/42; G01P3/44; G01P3/48; G01P3/4802
Claims Analysis
Total Claims: 3
Claim 1
Independent Claim
241 words
A system for converting an input signal having a frequency (f) into an output signal whose average amplitude is a function of the frequency (f) of the input signal comprising: constant pulse width generating means responsive to the input signal for providing a series of output pulses at the same frequency as the input signal, each pulse having an equal and predetermined duration; said constant pulse generating means comprising a high frequency oscillator for providing a series of reference pulses at a predetermined frequency, counting means and a bistable circuit, means including said bistable circuit and responsive to the input signal for coupling said reference pulses to said counting means and said bistable circuit, said bistable circuit responding to the first reference pulse to initiate a pulse output signal, said counting means providing an output signal after a predetermined number of reference pulses, and means for coupling said output signal to said bistable circuit to reset said bistable circuit to its original state to provide a pulse output signal having a predetermined duration; a source of voltage; an averaging circuit; and switching means coupled to the output of said pulse generating means for connecting said source of voltage to said averaging circuit for the duration of each output pulse provided by the pulse generating means whereby the averaging circuit provides an analog signal output having an average amplitude which is a function of the duty cycle of the pulse generating means.
Claim 2
Independent Claim
241 words
A system for converting an input signal having a frequency (f) into an output signal whose average amplitude is a function of the frequency (f) of the input signal comprising: constant pulse width generating means responsive to the input signal for providing a series of output pulses at the same frequency as the input signal, each pulse having an equal and predetermined duration; said constant pulse generating means comprising a high frequency oscillator for providing a series of reference pulses at a predetermined frequency, counting means and a bistable circuit, means including said bistable circuit and responsive to the input signal for coupling said reference pulses to said counting means and said bistable circuit, said bistable circuit responding to the first reference pulse to initiate a pulse output signal, said counting means providing an output signal after a predetermined number of reference pulses, and means for coupling said output signal to said bistable circuit to reset said bistable circuit to its original state to provide a pulse output signal having a predetermined duration; a source of voltage; an averaging circuit; and switching means coupled to the output of said pulse generating means for connecting said source of voltage to said averaging circuit for the duration of each output pulse provided by the pulse generating means whereby the averaging circuit provides an analog signal output having an average amplitude which is a function of the duty cycle of the pulse generating means.
Claim 3
Dependent Claim
136 words
A system as defined in claim 1 wherein: said averaging circuit includes a capacitor; said switching means comprises first and second transistors each having emitter, collector, and base electrodes, the emitter electrode of said first transistor being connected to the source of voltage and the emitter electrode of said second transistor being connected to circuit ground, resistance means connected between the collector electrodes of said transistors to thereby connect said first and second transistors in series between said voltage source and circuit ground; means for connecting said capacitor to said resistance means; and means for coupling the base electrodes of said first and second transistors to said pulse generating means, said transistors responding to the pulse output of said constant width pulse generating means to alternately couple the capacitor between the voltage source and circuit ground.
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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) | 1974-07-05 | 1975-01-04 | 1975-07-06 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1978-07-05 | 1979-01-04 | 1979-07-06 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1982-07-05 | 1983-01-04 | 1983-07-06 | $7700.00 | Window Closed / Lapsed |