US3950237A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Coulometric titrating devices
Assignee: Mitsubishi Chemical Corp
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Filing: 1975-03-31
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Granted: 1976-04-13
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Expires: 1995-03-31
Abstract
Abstract An electric quantity titrating device is disclosed of the type comprising electrolytic electrodes immersed in a solution to be analyzed for passing electrolytic current, detecting electrodes immersed in the solution, detecting apparatus connected across the detecting electrodes for producing a voltage signal which is used to continuously supply the electrolytic current to the electrolytic electrodes and integrating apparatus for integrating the electrolytic current for measuring the electric quantity required for the analysis until an end point is reached. A current controlling apparatus is provided in this system which includes a device for detecting the deviation of the voltage signal from a preset value at the end point, an amplifier for amplifying the deviation signal, and a current converter for converting the amplifed current into output current which is applied to the electrolytic electrodes. The integrating apparatus includes a device for converting the output from the current converter into a pulse train, and a counter for counting the pulse train.
Inventors
- 👤 Kiyoshi Arawa
- 👤 Seiji Ishikawa
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-08 14:03
CPC Classifications
G; G01; G01N; G01N27/00; G01N27/26; G01N27/416; G01N27/42; G01N27/423
Claims Analysis
Total Claims: 15
Claim 1
Independent Claim
165 words
In an electric quantity titrating device of the type comprising electrolytic electrodes immersed in a solution of a substance to be analyzed for passing electrolytic current through said solution, detecting electrodes immersed in said solution, detecting means connected across said detecting electrodes for producing a voltage signal which is used to continuously supply said electrolytic current to said electrolytic electrodes and means for integrating said electrolytic current for measuring the electric quantity required for the analysis until an end point is reached, the improvement which comprises: means for controlling electric current including means for detecting the deviation of said voltage signal from a preset value thereof at the end point, an amplifier for amplifying the deviation signal, a current converter for converting the amplified signal into output current, and means for supplying said output current to said electrolytic electrodes, and wherein said integrating means includes means for converting the output from said current converter into a pulse train, and means for counting said pulse train.
Claim 2
Dependent Claim
165 words
In an electric quantity titrating device of the type comprising electrolytic electrodes immersed in a solution of a substance to be analyzed for passing electrolytic current through said solution, detecting electrodes immersed in said solution, detecting means connected across said detecting electrodes for producing a voltage signal which is used to continuously supply said electrolytic current to said electrolytic electrodes and means for integrating said electrolytic current for measuring the electric quantity required for the analysis until an end point is reached, the improvement which comprises: means for controlling electric current including means for detecting the deviation of said voltage signal from a preset value thereof at the end point, an amplifier for amplifying the deviation signal, a current converter for converting the amplified signal into output current, and means for supplying said output current to said electrolytic electrodes, and wherein said integrating means includes means for converting the output from said current converter into a pulse train, and means for counting said pulse train.
Claim 3
Dependent Claim
28 words
The coulometric titrating device according to claim 1 which further comprises a blank current eliminater connected between the output of said current controlling means and said integrating means.
Claim 4
Dependent Claim
44 words
The coulometric titrating device according to claim 2 which further comprises a correction operator connected between said blank current eliminater and said integrating means for converting the unit of the electric quantity into that of the analyzed value and for correcting the sample quantity.
Claim 5
Dependent Claim
44 words
The current quantity titrating apparatus according to claim 2 wherein said blank eliminator comprises a memory device for storing the blank current at the end of a previous analysis and a subtractor for subtracting said blank current from the electrolytic current during subsequent analysis.
Claim 6
Dependent Claim
22 words
The coulometric titrating device according to claim 1 which further comprises an end point detecting means connected to receive said voltage signal.
Claim 7
Dependent Claim
61 words
The coulometric titrating device according to claim 5 wherein said end point detecting means comprises an integrator, means for initiating the operation of said integrator when said voltage signal reaches a predetermined low level, and means responsive to the output of said integrator for operating an alarm or display device when the output from said integrator reaches a predetermined high level.
Claim 8
Dependent Claim
39 words
The coulometric titrating device according to claim 1 wherein said detecting means comprises means for passing constant alternating current across said detecting electrodes and means for detecting the voltage drop across said detecting electrodes to produce said voltage signal.
Claim 9
Dependent Claim
50 words
The coulometric titrating device according to claim 1 which further comprises a correction operator connected between the output of said current controlling means and said integrating means for converting the unit of the electric quantity into that of the analyzed value and for correcting the sampled quantity of the sample.
Claim 10
Dependent Claim
62 words
The electric quantity titrating device according to claim 1 wherein said detecting means comprises an AC bridge circuit including said detecting electrodes as one arm thereof, an amplifier connected across the output terminals of said bridge circuit, and an insulating transformer connected to the output of said amplifier to electrically isolate the secondary voltage of the insulating transformer from said detecting electrodes.
Claim 11
Dependent Claim
39 words
The coulometric titrating device according to claim 1 wherein said detecting means comprises means for passing constant direct current across said detecting electrodes, and means for detecting the voltage drop across said detecting electrodes for producing said voltage signal.
Claim 12
Dependent Claim
42 words
The coulometric titrating device according to claim 1 wherein said detecting means comprises a DC bridge circuit including said detecting electrodes as one arm thereof and means for deriving out the unbalanced output of said DC bridge circuit as said voltage signal.
Claim 13
Dependent Claim
39 words
The coulometric titrating device according to claim 1 wherein said detecting means comprises means for applying constant alternating voltage across said detecting electrodes and means for detecting the current flowing across said detecting electrodes to produce said voltage signal.
Claim 14
Dependent Claim
113 words
The coulometric titrating device according to claim 1 wherein said current controller comprises a proportional amplifier, an integrator, a voltage-current converter connected to the output of said integrator, means for determining the proportionality gain of said proportional amplifier, a low level detecter responsive to said voltage signal, and means for supplying the output from said voltage-current converter to said electrolytic electrodes as the electrolytic current, whereby until a point near the end point is reached said voltage signal is applied to said voltage-current converter through said proportional amplifier and around said integrator whereas near said end point said voltage signal is applied to said voltage-current converter through said proportional amplifier and said integrator.
Claim 15
Dependent Claim
66 words
The coulometric titrating apparatus according to claim 13 wherein said means for determining the proportionality gains of said amplifier and said low level detecter are arranged such that until a point near the end point is reached said electrolytic current is controlled at a constant rate determined by said proportionality gain determining means, whereas thereafter said electrolytic current is controlled in proportion to said voltage signal.
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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) | 1979-04-13 | 1979-10-13 | 1980-04-13 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1983-04-13 | 1983-10-13 | 1984-04-13 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1987-04-13 | 1987-10-13 | 1988-04-13 | $7700.00 | Window Closed / Lapsed |