US3701014A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Measuring system employing a sensing loop and a reference loop in bucking relationship to provide current-to-voltage conversion
Assignee: Individual
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Filing: 1970-01-23
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Granted: 1972-10-24
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Expires: 1990-01-23
Abstract
Abstract This invention is a current-to-voltage conversion system. The use of the conversion system is in measuring AC or DC signals and in sound reproduction systems. The DC conversion system comprises a reference loop and a sensing loop connected in current bucking relation. A transistorized ''''zero junction circuit'''' senses the current differential between the two loops and generates an output voltage that is related to the current differential. The DC conversion system is used to sense current changes for a measuring instrument. the AC conversion system is used to sense output current flow in an audio reproduction system and to provide a feedback voltage directly related to the current flow, for example.
Inventors
- 👤 Chien San Wang
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-03 20:58
CPC Classifications
H; H03; H03F; H03F3/00; H03F3/45; H03F3/45071; H03F3/181; H03F3/183
Claims Analysis
Total Claims: 9
Claim 1
Independent Claim
139 words
An electrical measuring network comprising: a sensing branch; a reference branch; a zero junction branch, said sensing branch, said reference branch and said zero junction branch all being connected in parallel, said zero junction branch comprising: i. a first circuit, including a first active circuit element, connected so as to detect the current difference between the sensing branch and the reference branch and converting said current difference into a voltage; and, ii. a second circuit, including a second active circuit element, for producing a voltage that is essentially equal to, but opposite in sign from, the voltage drop across said first circuit, said first and second circuits being connected together so that the combined voltage drop across said zero junction branch is essentially zero; and, a measuring device connected to said first circuit so as to measure said voltage.
Claim 2
Dependent Claim
139 words
An electrical measuring network comprising: a sensing branch; a reference branch; a zero junction branch, said sensing branch, said reference branch and said zero junction branch all being connected in parallel, said zero junction branch comprising: i. a first circuit, including a first active circuit element, connected so as to detect the current difference between the sensing branch and the reference branch and converting said current difference into a voltage; and, ii. a second circuit, including a second active circuit element, for producing a voltage that is essentially equal to, but opposite in sign from, the voltage drop across said first circuit, said first and second circuits being connected together so that the combined voltage drop across said zero junction branch is essentially zero; and, a measuring device connected to said first circuit so as to measure said voltage.
Claim 3
Dependent Claim
30 words
An electrical measuring network as claimed in claim 1 including an amplifier connected between said first circuit and said measuring device for negating the effect of a steady state current.
Claim 4
Dependent Claim
40 words
An electrical measuring network as claimed in claim 2 wherein said first active circuit element is a first transistor of one polarity and wherein said second active circuit element is a second transistor of opposite polarity to said first transistor.
Claim 5
Dependent Claim
36 words
An electrical measuring network as claimed in claim 3 wherein said sensing branch includes a sensing element and a first voltage source and wherein said reference branch includes a first resistor and a second voltage source.
Claim 6
Dependent Claim
65 words
An electrical measuring circuit as claimed in claim 4 wherein said first resistor is connected in series with said second voltage source between the emitters of said first and second transistors and wherein said sensing element and said first voltage source are also connected in series between the emitters of said first and second transistors, said first and second voltage sources having oppositely connected poles.
Claim 7
Dependent Claim
81 words
An electrical measuring network as claimed in claim 5 including: a third voltage source; a second resistor, said second resistor being connected in series with said third voltage source between the base-collector terminals of said first transistor; a third resistor, said third resistor being connected between the bases of said first and second transistors and the junction between said first resistor and second voltage source; and, a fourth resistor, said forth resistor being connected between the base-collector terminals of second transistor.
Claim 8
Dependent Claim
32 words
An electrical measuring network as claimed in claim 6 wherein said amplifier is a difference amplifier having a reference voltage to compensate for the steady state voltage of said zero junction branch.
Claim 9
Dependent Claim
16 words
An electrical measuriNg circuit as claimed in claim 7 wherein said sensing means is a thermistor.
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) | 1975-10-24 | 1976-04-24 | 1976-10-24 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1979-10-24 | 1980-04-24 | 1980-10-24 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1983-10-24 | 1984-04-24 | 1984-10-24 | $7700.00 | Window Closed / Lapsed |