Apparatus for analysing a plurality of mixed gases

• US 3,893,770 A
• Filed: 09/04/1973
• Issued: 07/08/1975
• Est. Priority Date: 09/05/1972
• Status: Expired due to Term

• Current Assignee: Chiaki Shimbo, Katsumi Takami, Kyo Suda
• Original Assignee: Chiaki Shimbo, Katsumi Takami, Kyo Suda
• Inventors: Takami, Katsumi, Shimbo, Chiaki, Suda, Kyo
• Primary Examiner(s): Wibert, Ronald L.
• Assistant Examiner(s): Evans, F. L.
• Application Number:
  US05/394,256
• Time in Patent Office: 672 Days
• Field of Search: 356/51,96-98,201,204-206 250/343-345,339
• US Class Current: 356/328
• CPC Class Codes: G01N 21/3504 for analysing gases, e.g. multi-gas analysis
• CPC Class Codes: G01N 2201/1215 for interfering gases

Abstract

In the analysis of mixed gases, electrical signals corresponding to the absorption spectra of a specific wavelength range corresponding to the component gases whose mutual spectrophotometric interferences are irreversible are corrected by other electrical signals simulating the interferences between the component gases.

Claims

1. AN APPARATUS FOR ANALYZING A COMPOSITE GAS COMPRISING:

MEANS FOR OBTAINING AN ABSORPTION SPECTRUM OF EACH OF NO2 GAS, SO2 GAS, AND NO GAS, THE INTERFERENCES BETWEEN EACH GAS BEING IRREVERABLE;

MEANS FOR CONVERTING SAID EACH RESPECTIVE ABSORPTION SPECTRUM INTO A FIRST A SECOND A THIRD ELECTRICAL SIGNAL IN ACCORDANCE WITH THE INTENSITY OF THE SPECTRUM THEREOF, MEANS FOR GENERATING A FOURTH ELECTRICAL SIGNAL FOR SIMULATING THE INTERFERANCE BETWEEN SAID NO2 GAS AND SO2 GAS, WHICH HAS THE FIRST ELECTRICAL SIGNAL AS AN INPUT SIGNAL, A FIRST ADDER WHICH HAS THE FORTH ELECTRICAL SIGNAL AND THE SECOND ELECTRICAL SIGNAL AS AN INPUT SIGNAL, MEANS FOR GENERATING A SIXTH ELECTRICAL SIGNAL FOR SIMULATING THE INTERFERANCE BETWEEN SAID SO2 GAS AND NO GAS WHICH HAS A FIFTH ELECTRICAL SIGNAL DERIVED FROM SAID ADDER AS AN INPUT SIGNAL, A FIRST SUBTRACTOR WHICH HAS THE THIRD ELECTRICAL SIGNAL AND THE SIXTH SIGNAL AS AN INPUT SIGNAL, MEANS FOR GENERATING A SEVENTH ELECTRICAL SIGNAL FOR SIMULATING THE INTERFERANCE BETWEEN SAID NO2 GAS AND SAID NO GAS WHICH HAS THE FIRST ELECTRICAL SIGNAL AS AN INPUT, A SECOND SUBSTRACTOR WHICH HAS THE SEVENTH ELECTRICAL SIGNAL AND A EIGHTH ELECTRICAL SIGNAL DERIVED FROM THE FIRST SUB TRACTOR AS AN INPUT SIGNAL.

2. An apparatus for analyzing a composite gas comprising:

first means for obtaining an absorption spectrum of each respective component gas in said composite gas containing a plurality of gases by passing a beam of light through said composite gas, the respective interference between the component gases being irreversible;

second means, responsive to said first means, for convering each respective absorption spectrum into a respective signal representative thereof;

third means, responsive to a first of the signals representative of the spectrum of a first of said component gases, for generating a first output signal which simulates the interference between said first gas and a second of said gases;

fourth means, responsive to said second and third means, for combining a second of the signals representative of the spectrum of said second of said component gases, and providing a second output signal representative of said second gas with respect to which the interference between said first and said second of said gases has been eliminated;

fifth means, responsive to the output of said fourth means, for generating a third output signal which simulates the interference between a third component gas and said second component gas;

sixth means, responsive to said second and fifth means, for combining a third of the signals representative of the spectrum of a respective third component gas, and providing a fourth output signal representative of said third gas with respect to which the interference between said second and third gases has been eliminated;

seventh means, responsive to said first of the signals representative of said first of said component gases, for generating a fifth output signal which simulates the interference between said first gas and said third gas; and

eighth means, responsive to said sixth and seventh means, for combining said fourth and fifth output signals, and providing a sixth output signal representative of said third gas with respect to which the interference between said first and said third gases has been eliminated.