Patent US3603979A successfully refreshed from Google Patents.
US3603979A
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US
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Digital system including temperature compensating means
Assignee: Bendix Corp
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Filing: 1969-09-04
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Granted: 1971-09-07
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Expires: 1989-09-04
Abstract
Abstract A two-speed system having a counter for providing a digital output corresponding to a condition in which a resolver provides an analog error signal corresponding to the difference between the condition and the digital output. The analog error signal is converted to pulses which are counted by the counter. Followup means connected to the counter and to the resolver nulls the error signal when the count in the counter corresponds to the condition. The null is defined by a pair of reference voltages and the count is stopped when the amplitude of the error signal is greater than one reference voltage and less than the other reference voltage. The counting rate of the counter is controlled by providing a high frequency pulse train to the counter when the error signal is above a predetermined amplitude and a low frequency pulse train when the error signal is below the predetermined amplitude. Independent high and low temperature compensation provides accurate operation over wide temperature range and eliminates trial and error adjustment.
Inventors
- 👤 Henry Kosakowski
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-24 20:02
CPC Classifications
H; H03; H03M; H03M1/00; H03M1/12; H03M1/48; H03M1/485
Claims Analysis
Total Claims: 8
Claim 1
Independent Claim
221 words
A system for providing a digital output corresponding to a condition, comprising: counting means providing the digital output; signal means providing an error signal corresponding to the difference between the digital output and the condition; means for controlling the counting rate connected to the signal means and to the counting means and providing a pulse train of one frequency when the error signal is above a predetermined amplitude and a pulse train of another lesser frequency when the error signal is below the predetermined amplitude; means connected to the counting means and to the signal means for nulling the error signal so that the digital output from the counting means corresponds to the condition when the error signal is at null; means connected to the signal means for sampling the error signal; means connected to the sampling means for holding the sampled error signal; means for comparing the held error signal to reference signals defining null limits for the error signal; and switching means connected to the controlling means, the comparing means and the counting means and controlled by the comparing means for passing one of the pulse trains from the controlling means to the counting means when the error signal is outside the null limits and for blocking the pulse train when the error signal is within the null limits.
Claim 2
Independent Claim
221 words
A system for providing a digital output corresponding to a condition, comprising: counting means providing the digital output; signal means providing an error signal corresponding to the difference between the digital output and the condition; means for controlling the counting rate connected to the signal means and to the counting means and providing a pulse train of one frequency when the error signal is above a predetermined amplitude and a pulse train of another lesser frequency when the error signal is below the predetermined amplitude; means connected to the counting means and to the signal means for nulling the error signal so that the digital output from the counting means corresponds to the condition when the error signal is at null; means connected to the signal means for sampling the error signal; means connected to the sampling means for holding the sampled error signal; means for comparing the held error signal to reference signals defining null limits for the error signal; and switching means connected to the controlling means, the comparing means and the counting means and controlled by the comparing means for passing one of the pulse trains from the controlling means to the counting means when the error signal is outside the null limits and for blocking the pulse train when the error signal is within the null limits.
Claim 3
Dependent Claim
89 words
A system of the kind described in claim 1 in which the sampling means includes a zero crossover detector providing a pulse when an alternating current reference voltage, phase related to the error signal, crosses the zero amplitude level, a monostable multivibrator connected to the detector and providing a sampling pulse in response to alternate pulses from the detector, and a sampling circuit, connected to the signal means, to the multivibrator and to the holding means, samples the error signal in response to the sampling pulses from the multivibrator.
Claim 4
Independent Claim
230 words
A system for providing a digital output corresponding to a condition, comprising: counting means providing the digital output; signal means providing an alternating current error signal corresponding to the difference between the digital output and the condition; means for controlling the counting rate connected to the signal means and to the counting means and providing a pulse train of one frequency when the error signal is above a predetermined amplitude and a pulse train of another frequency when the error signal is below the predetermined amplitude; means connected to the counting means and to the signal means for nulling the error signal so that the digital output from the counting means corresponds to the condition when the error signal is at null; first temperature compensating means connected to the nulling means for applying a compensating signal to the nulling means in response to an increase in ambient temperature from a reference temperature level; and second temperature compensating means including a voltage divider network having a plurality of grounded resistors and receiving an alternating signal phase related to the alternating error signal, and connected to the nulling means for independently applying another compensating signal to the nulling means in response to a decrease in temperature from the temperature level, and a thermistor connected across the grounded resistors for changing said compensating signal as the temperature decreases below the reference temperature level.
Claim 5
Independent Claim
230 words
A system for providing a digital output corresponding to a condition, comprising: counting means providing the digital output; signal means providing an alternating current error signal corresponding to the difference between the digital output and the condition; means for controlling the counting rate connected to the signal means and to the counting means and providing a pulse train of one frequency when the error signal is above a predetermined amplitude and a pulse train of another frequency when the error signal is below the predetermined amplitude; means connected to the counting means and to the signal means for nulling the error signal so that the digital output from the counting means corresponds to the condition when the error signal is at null; first temperature compensating means connected to the nulling means for applying a compensating signal to the nulling means in response to an increase in ambient temperature from a reference temperature level; and second temperature compensating means including a voltage divider network having a plurality of grounded resistors and receiving an alternating signal phase related to the alternating error signal, and connected to the nulling means for independently applying another compensating signal to the nulling means in response to a decrease in temperature from the temperature level, and a thermistor connected across the grounded resistors for changing said compensating signal as the temperature decreases below the reference temperature level.
Claim 6
Dependent Claim
162 words
A system of the kind described in claim 3 wherein: the first temperature compensating means includes means for providing a control signal when the ambient temperature increases above the reference tempeRature level, and means connected to the control signal means and controlled by the control signal to provide the first mentioned temperature compensating signal when the temperature increases above the reference temperature level; and the control signal means including a voltage divider receiving an alternating current voltage, phase related to the error signal, and providing a variable output which may be changed to calibrate the first temperature compensating means, an amplifier, a feedback resistor connected between an input and an output of the amplifier, and a thermistor connecting the voltage divider to the input of the amplifier and cooperating with the feedback resistor to change the gain of the amplifier so that the control signal provided by the amplifier increases in amplitude as the ambient temperature increases above the reference temperature level.
Claim 7
Dependent Claim
93 words
A system of the kind described in claim 4 in which the compensating signal means includes a network providing two equal outputs when the ambient temperature is at the reference temperature level and providing unequal outputs when the ambient temperature is above the reference temperature level, where the difference between the outputs corresponds to the increase in the ambient temperature, in response to the control signal from the amplifier; and means connected to the network for providing the first mentioned compensating signal in accordance with the difference between the outputs from the network.
Claim 8
Dependent Claim
72 words
A system of the kind described in claim 5 in which the network includes a resistor connecting the amplifier to one input of the difference means, and a thermistor connecting the amplifier to another input of the difference means, the thermistor having a resistance value equal to that of the resistor at the reference temperature level which decreases as the temperature increases to cause the inputs to the difference means to differ.
References Cited (Backward Citations)
US2500581A
Cited
US2945123A
Cited
US3201781A
Cited
US3419819A
Cited
US3419800A
Cited
US3443070A
Cited
US3521269A
Cited
US3463999A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1974-09-06 | 1975-03-08 | 1975-09-07 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1978-09-06 | 1979-03-08 | 1979-09-07 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1982-09-06 | 1983-03-08 | 1983-09-07 | $7700.00 | Window Closed / Lapsed |