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US4266942A Expired / Lapsed US ⏱️ 0.0 years remaining

Method for the automatic electro-chemical determination of the end point of a titration

Assignee: Siemens AG
•
Filing: 1980-01-21
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Granted: 1981-05-12
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Expires: 2000-01-21
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Abstract

Abstract A method for the automatic, electro-chemical determination of the end point of titration utilizing an initial, continuous addition of the titrant, up to a predetermined value, followed by a step-by-step addition with a resting time inserted therebetween for stabilization of the solution is disclosed. As the titrant is being added to the bath sample in constant volume units, a measured value is formed after every such addition. The difference to the preceding measurement is determined and the three consecutive differences of greatest magnitude are utilized in a mathematical formula for calculating the end point. The titration ceases when the greatest difference lies between two lesser values.

Inventors

  • 👤 Chris Vandenbossche
  • 👤 Jacky Vanhumbeeck

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-11-05 09:53
CPC Classifications
G; G01; G01N; G01N31/00; G01N31/16; G01N31/162; G01N31/164

Claims Analysis

Total Claims: 8
Claim 1
Independent Claim 144 words
An improved method for the automatic, electro-chemical determination of the end point of a titration of the type in which the titrant is added to a bath sample in constant volume units, a measured value is formed after every titrant addition, the difference from the preceding value is formed after every measured value formation, and the three consecutive additions having the greatest caculated differences are utilized in calculating the end point and wherein the titration is interupted when the greatest difference lies between two lesser differences, the improvement comprising: continuously adding the titrant to the initial bath sample, up to a selectively predetermined value thereafter adding the titrant in constant volume units in a step-wise manner; and separating each of said constant volume additions by a resting period of time in order to allow the solution to stabilize prior to obtaining the measured value.
Claim 2
Dependent Claim 144 words
An improved method for the automatic, electro-chemical determination of the end point of a titration of the type in which the titrant is added to a bath sample in constant volume units, a measured value is formed after every titrant addition, the difference from the preceding value is formed after every measured value formation, and the three consecutive additions having the greatest caculated differences are utilized in calculating the end point and wherein the titration is interupted when the greatest difference lies between two lesser differences, the improvement comprising: continuously adding the titrant to the initial bath sample, up to a selectively predetermined value thereafter adding the titrant in constant volume units in a step-wise manner; and separating each of said constant volume additions by a resting period of time in order to allow the solution to stabilize prior to obtaining the measured value.
Claim 3
Dependent Claim 26 words
An improved method for the automatic, electro-chemical determination of the end point of a titration as described in claim 1, wherein said resting period is constant.
Claim 4
Dependent Claim 31 words
An improved method for the automatic, electro-chemical determination of the end point of a titration as described in claim 1, wherein said resting period is proportional to the previous calculated difference.
Claim 5
Dependent Claim 38 words
An improved method for the automatic, electro-chemical determination of the end point of a titration as described in claim 1, in which said measured value is a pH value wherein the selectively predetermined value is a pH value.
Claim 6
Dependent Claim 29 words
An improved method for the automatic, electro-chemical determination of the end point of a titration as described in claim 1, wherein said selectively predetermined value is a volume value.
Claim 7
Dependent Claim 27 words
An improved method for the automatic, electro-chemical determination of the end point of a titration as described in claim 1, wherein the measured values are potentiometrically attained.
Claim 8
Dependent Claim 115 words
An improved method for the automatic, electro-chemical determination of the end point of a titration as described in claim 1, in which the end point is automatically calculated according to the following formulas: V E =V max +ΔV R -ρΔV R , when Δ1 is after Δ0; and V E =V max +ΣΔV R , when Δ1 is before Δ0, wherein ρ, R, and R 2 are auxiliary magnitudes which are determined as follows: ρ=0.5 R 2 -0.2 R 2 ; R 1 =Δ1/Δ0; and R 2 =Δ2/Δ1, and wherein V max signifies the total volume before the largest difference Δ0, and Δ0, Δ1, and Δ2 signify the calculated differences arranged according to decreasing size.

References Cited (Backward Citations)

US3157471A Cited
US3195982A Cited
US3246952A Cited
US3769178A Cited
US4058365A Cited
US4180440A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1984-05-11 1984-11-10 1985-05-12 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1988-05-11 1988-11-10 1989-05-12 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1992-05-11 1992-11-10 1993-05-12 $7700.00 Window Closed / Lapsed

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