Patent US3184710A successfully refreshed from Google Patents.
US3875503A
Expired / Lapsed
US
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Dual slope type resistance deviation measuring apparatus
Assignee: Yokogawa Electric Corp
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Filing: 1973-11-13
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Granted: 1975-04-01
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Expires: 1993-11-13
Abstract
Abstract A resistance deviation measuring device, of the type used for measuring a temperature with temperature-sensitive resistance and for obtaining a digital signal representing the measured temperature, is characterized by a simple and reliable arrangement operating with the characteristics of a dual slope type analog-digital converter, i.e., with an integrator for first integrating an unknown analog signal for a predetermined time period and for then integrating a reference signal of inverse polarity with respect to the analog signal until the integrator is restored to its initial value, and with digital counting means for digitally measuring a time interval ending when the integrating means is restored to its initial value. The resistance deviation measuring device of the present invention connects the unknown temperature-sensitive resistance to a reference resistance in series, and uses a series voltage source to generate the same current flow through both resistances to produce the unknown analog signal and reference signal respectively. A switch connects the unknown resistance to the integrator for the predetermined time period, and then connects the reference resistance to the integrator until it is restored to its initial value. A timing circuit initiates the counting of the time interval measured by the digital counting means a predetermined amout of time, equal to the predetermined time period, after the reference signal is connected to the integrator. The digital counting means then digitally represents the deviation of the unknown resistance from the reference resistance.
Inventors
- 👤 Eiji Hayashi
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-22 21:01
CPC Classifications
G; G01; G01R; G01R27/00; G01R27/02; G01K; G01K1/00; G01K1/02; G01K1/028; H; H03; H03M; H03M1/00; H03M1/12; H03M1/50; H03M1/52
Claims Analysis
Total Claims: 9
Claim 1
Independent Claim
218 words
A resistance deviation measuring device for determining the deviation of an unknown resistance from a predetermined resistance value with dual slope type converter means having integrating means for first integrating an unknown analog signal for a predetermined time period and for then integrating a reference signal of inverse polarity with respect to the analog signal until the integrating means is restored to its initial value, and having digital counting means digitally measuring a time interval ending when the integrating means is restored to its initial value, the resistance deviation measuring device being characterized by: a reference resistance; means for generating the same current flow through the unknown resistance and the reference resistance to produce thereacross the unknown analog signal and the reference signal respectively; switch means for first connecting the analog signal developed across the unknown resistance to the integrating means for said predetermined time period and then connecting the reference signal develoPed across the reference resistance with inverse polarity to the integrating means until it is restored to its initial value; and means for initiating the time interval measured by the digital counting means a predetermined amount of time after the reference signal is connected to the integrating means, whereby the digital counting means digitally represents the deviation of the unknown resistance from a predetermined resistance value.
Claim 2
Dependent Claim
218 words
A resistance deviation measuring device for determining the deviation of an unknown resistance from a predetermined resistance value with dual slope type converter means having integrating means for first integrating an unknown analog signal for a predetermined time period and for then integrating a reference signal of inverse polarity with respect to the analog signal until the integrating means is restored to its initial value, and having digital counting means digitally measuring a time interval ending when the integrating means is restored to its initial value, the resistance deviation measuring device being characterized by: a reference resistance; means for generating the same current flow through the unknown resistance and the reference resistance to produce thereacross the unknown analog signal and the reference signal respectively; switch means for first connecting the analog signal developed across the unknown resistance to the integrating means for said predetermined time period and then connecting the reference signal develoPed across the reference resistance with inverse polarity to the integrating means until it is restored to its initial value; and means for initiating the time interval measured by the digital counting means a predetermined amount of time after the reference signal is connected to the integrating means, whereby the digital counting means digitally represents the deviation of the unknown resistance from a predetermined resistance value.
Claim 3
Dependent Claim
73 words
A resistance deviation measuring device as claimed in claim 1 wherein the time interval measured by the digital counting means is initiated a predetermined amount of time after the reference voltage is connected to the integrating means which is equal to the predetermined period of time for which the analog signal is connected to the integrating means, whereby the digital counting means represents the deviation of the unknown resistance from the reference resistance.
Claim 4
Dependent Claim
35 words
A resistance deviation measuring device as claimed in claim 2 wherein the unknown resistance is a temperature-sensing resistance, and wherein the reference resistance is provided with a predetermined resistance value representing a predetermined temperature value.
Claim 5
Dependent Claim
54 words
A resistance deviation measuring device as claimed in claim 1 further comprising timing signal means generating timing signal pulses, said switch means being responsive to the timing signal means to measure said predetermined period of time, and said digital counting means being responsive to said timing signal means to initiate its measured time interval.
Claim 6
Dependent Claim
79 words
A resistance deviation measurement device as claimed in claim 4 wherein said timing signal pulses include a first pulse to which the switch means responds by connecting the analog signal to the integrating means, a second pulse to which the switch means responds by connecting the reference signal to the integrating means, and a third pulse to which the digital counting means responds by initiating the measured interval, said first, second and third pulses being equally spaced in time.
Claim 7
Dependent Claim
40 words
A resistance deviation measuring device as claimed in claim 1 wherein said switching means is arranged to disconnect the integrating means from both the analog signal and the reference signal after the integrating means is restored to its initial value.
Claim 8
Dependent Claim
46 words
A resistance deviation measuring device as claimed in claim 1 wherein said reference resistance and said unknown resistance are connected in series with each other, and wherein the means for generating the same current flow through the unknown resistance and reference resistance comprises a voltage source.
Claim 9
Dependent Claim
71 words
A resistance deviation measuring device as claimed in claim 7 wherein the junction of the unknown resistance and reference resistance is connected to the ground level of the integrating means, and wherein said switch means comprises switch contacts respectively connected to said resistances opposite said ground connection, and comprises means for alternatively connecting the contacts to the integrating means, whereby the voltages across the resistances are applied to the integrating 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) | 1978-03-31 | 1978-09-30 | 1979-04-01 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-03-31 | 1982-09-30 | 1983-04-01 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-03-31 | 1986-09-30 | 1987-04-01 | $7700.00 | Window Closed / Lapsed |