Apparatus for analyzing a mixture of substances by selective absorption of infrared radiation

• US 3,162,761 A
• Filed: 05/29/1961
• Issued: 12/22/1964
• Est. Priority Date: 06/03/1960
• Status: Expired due to Term

• Current Assignee: Karl Luft
• Original Assignee: Karl Luft
• Inventors: Luft, Karl
• Application Number:
  US04/113,467
• Time in Patent Office: 1,303 Days
• US Class Current: 250/344
• CPC Class Codes: G01N 21/3504 for analysing gases, e.g. multi-gas analysis
• CPC Class Codes: G01N 21/37 using pneumatic detection opto-acoustic detection G01N21/1702

Claims

1. AN APPARATUS FOR ANALYZING A MIXTURE OF SUBSTANCES TO MEASURE THE RELATIVE AMOUNT, IN SAID MIXTURE, OF A GIVEN COMPONENT THEREOF CAPABLE OF SELECTIVELY ABSORBING RAYS OF WAVELENGTHS BELONGING TO A GIVEN RANGE OF WAVELENGTHS, WHICH APPARATUS COMPRISES, IN COMBINATION, A MEASUREMENT CELL ARRANGED TO CONTAIN THE MIXTURE TO BE ANALYZED, A REFERENCE CELL ARRANGED TO CONTAIN A REFERENCE SUBSTANCE, MEANS FOR FORMING TWO SUBSTANTIALLY IDENTICAL RAY BEAMS, ONE OF SAID BEAMS BEING CALLED MEASUREMENT BEAM AND THE OTHER ONE REFERENCE BEAM, A DETECTOR DEVICE LOCATED IN FIXED POSITION WITH RESPECT TO SAID CELLS, MEANS FOR PASSING THE MEASUREMENT BEAM INTERMITTENTLY FOR FIRST RECURRENT TIME PERIODS THROUGH SAID MEASUREMENT CELL AND ONTO SAID DETECTOR DEVICE, MEANS FOR PASSING THE REFERENCE BEAM INTERMITTENTLY THROUGH SAID REFERENCE CELL AND ONTO SAID DETECTOR DEVICE DURING SECOND RECURRENT TIME PERIODS CORRESPONDING TO THE INTERVALS BETWEEN SAID FIRST RECURRENT TIME PERIODS, SAID DETECTOR DEVICE COMPRISING TWO DISTINCT DETECTOR ELEMENTS FOR PRODUCING SIGNALS IN RESPONSE TO THE ACTION OF RAYS THEREON, THE FIRST OF SAID DETECTOR ELEMENTS SELECTIVELY SENSITIVE TO RAYS OF WAVELENGTHS CORRESPONDING TO THE MAXIMUM OF ABSORPTION BY SAID COMPONENT IN SAID RANGE OF WAVELENGTHS, SAID MAXIMUM ABSORPTION RAYS FORMING A FIRST PARTIAL RADIATION OF SAID BEAMS, THE SECOND OF SAID DETECTOR ELEMENTS BEING SENSITIVE TO THE RAYS OF A SECOND PARTIAL RADIATION OF SAID BEAMS COMPRISING RAYS OF WAVELENGTHS DIFFERENT FROM THOSE OF SAID MAXIMUM ABSORPTION RAYS, MEANS FOR APPLYING THE FIRST AND SECOND PARTIAL RADIATIONS OF SAID MEASUREMENT BEAM TO SAID FIRST AND SECOND DETECTOR ELEMENTS, RESPECTIVELY, FOR SAID FIRST RECURRENT TIME PERIODS, MEANS FOR APPLYING THE FIRST AND SECOND PARTIAL RADIATION OF SAID REFERENCE BEAM TO SAID FIRST AND SECOND DETECTOR ELEMENTS, RESPECTIVELY, FOR SAID SECOND RECURRENT TIME PERIODS, AND MEANS OPERATIVELY CONNECTED WITH BOTH OF SAID DETECTOR ELEMENTS FOR COMPARING THE VALUE OF THE SIGNAL DELIVERED BY SAID FIRST DETECTOR ELEMENT RELATIVELY TO THE VALUE OF THE SIGNAL DELIVERED SIMULTANEOUSLY BY SAID SECOND DETECTOR ELEMENT, DURING THE FIRST RECURRENCE PERIODS, WITH THE VALUE OF THE SIGNAL DELIVERED BY SAID FIRST DETECTOR ELEMENT RELATIVELY TO THE VALUE OF THE SIGNAL DELIVERED SIMULTANEOUSLY BY SAID SECOND DETECTOR ELEMENT, DURING THE SECOND RECURRENCE PERIODS.