US3715657A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Transducer for converting selected environmental parameter differentials to frequency differentials
Assignee: Universal Oil Products Co
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Filing: 1970-12-28
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Granted: 1973-02-06
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Expires: 1990-12-28
Abstract
Abstract To form a transducer, two uniformly d.c. biased signal detector means are connected in parallel. Each of these signal detector means includes a variable resistor that controls the output frequency of that signal detector means. The variable resistors are located in environments differing only in a parameter for which differential measurement is desired. Such parameters include temperature, thermal absorption, and other variables that affect electrical current flow in the resistors. A non-uniform change in the variable resistors changes the frequency differential existing between the two signal detector means.
Inventors
- 👤 R Sampson
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-26 17:55
CPC Classifications
G; G01; G01N; G01N27/00; G01N27/02; G01N27/04; G01N27/12; G01N27/122
Claims Analysis
Total Claims: 4
Claim 1
Independent Claim
258 words
In a chromatography detector for quantitatively measuring the percentage of each component of a fluid mixture, including a thermal absorption sensitive resistor located in a carrier stream containing said fluid mixture and an identical reference resistor located in a reference carrier stream, the improvement comprising uniformly d.c. biased identical first and second signal detector means, wherein said thermal absorption sensitive resistor is connected to and controls the output frequency of said first signal detector means and said reference resistor is connected to and controls the output frequency of said second signal detector means, said signal detector means being comprised of first and second input terminals, an input circuit having a fixed resistor and a capacitor connected in series between said first and second input terminals, first and second output terminals, a load resistor connected between said output terminals, a programmable unijunction transistor having an anode, a gate, and a cathode with said anode connected to said input circuit between said fixed resistor and said capacitor and with said cathode connected to said first of the aforesaid output terminals which is connected to said capacitor through said load resistor, said second output terminal and said second input terminal, a resistor connected between said gate and said cathode; said thermal absorption sensitive resistor and said reference resistor being connected between said gate and said first input terminal of said first and second signal detector means respectively, whereby a change in the quantitative composition of said mixture causes a change in frequency differential between said first and second signal detector means.
Claim 2
Dependent Claim
258 words
In a chromatography detector for quantitatively measuring the percentage of each component of a fluid mixture, including a thermal absorption sensitive resistor located in a carrier stream containing said fluid mixture and an identical reference resistor located in a reference carrier stream, the improvement comprising uniformly d.c. biased identical first and second signal detector means, wherein said thermal absorption sensitive resistor is connected to and controls the output frequency of said first signal detector means and said reference resistor is connected to and controls the output frequency of said second signal detector means, said signal detector means being comprised of first and second input terminals, an input circuit having a fixed resistor and a capacitor connected in series between said first and second input terminals, first and second output terminals, a load resistor connected between said output terminals, a programmable unijunction transistor having an anode, a gate, and a cathode with said anode connected to said input circuit between said fixed resistor and said capacitor and with said cathode connected to said first of the aforesaid output terminals which is connected to said capacitor through said load resistor, said second output terminal and said second input terminal, a resistor connected between said gate and said cathode; said thermal absorption sensitive resistor and said reference resistor being connected between said gate and said first input terminal of said first and second signal detector means respectively, whereby a change in the quantitative composition of said mixture causes a change in frequency differential between said first and second signal detector means.
Claim 3
Dependent Claim
258 words
In a chromatography detector for quantitatively measuring the percentage of each component of a fluid mixture, including a thermal absorption sensitive resistor located in a carrier stream containing said fluid mixture and an identical reference resistor located in a reference carrier stream, the improvement comprising uniformly d.c. biased identical first and second signal detector means, wherein said thermal absorption sensitive resistor is connected to and controls the output frequency of said first signal detector means and said reference resistor is connected to and controls the output frequency of said second signal detector means, said signal detector means being comprised of first and second input terminals, an input circuit having a fixed resistor and a capacitor connected in series between said first and second input terminals, first and second output terminals, a load resistor connected between said output terminals, a programmable unijunction transistor having an anode, a gate, and a cathode with said anode connected to said input circuit between said fixed resistor and said capacitor and with said cathode connected to said first of the aforesaid output terminals which is connected to said capacitor through said load resistor, said second output terminal and said second input terminal, a resistor connected between said gate and said cathode; said thermal absorption sensitive resistor and said reference resistor being connected between said gate and said first input terminal of said first and second signal detector means respectively, whereby a change in the quantitative composition of said mixture causes a change in frequency differential between said first and second signal detector means.
Claim 4
Dependent Claim
258 words
In a chromatography detector for quantitatively measuring the percentage of each component of a fluid mixture, including a thermal absorption sensitive resistor located in a carrier stream containing said fluid mixture and an identical reference resistor located in a reference carrier stream, the improvement comprising uniformly d.c. biased identical first and second signal detector means, wherein said thermal absorption sensitive resistor is connected to and controls the output frequency of said first signal detector means and said reference resistor is connected to and controls the output frequency of said second signal detector means, said signal detector means being comprised of first and second input terminals, an input circuit having a fixed resistor and a capacitor connected in series between said first and second input terminals, first and second output terminals, a load resistor connected between said output terminals, a programmable unijunction transistor having an anode, a gate, and a cathode with said anode connected to said input circuit between said fixed resistor and said capacitor and with said cathode connected to said first of the aforesaid output terminals which is connected to said capacitor through said load resistor, said second output terminal and said second input terminal, a resistor connected between said gate and said cathode; said thermal absorption sensitive resistor and said reference resistor being connected between said gate and said first input terminal of said first and second signal detector means respectively, whereby a change in the quantitative composition of said mixture causes a change in frequency differential between said first and second signal detector means.
References Cited (Backward Citations)
No citation records indexed.
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1976-02-06 | 1976-08-07 | 1977-02-06 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-02-06 | 1980-08-07 | 1981-02-06 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-02-06 | 1984-08-07 | 1985-02-06 | $7700.00 | Window Closed / Lapsed |