Method and apparatus for automatically analyzing fluids

Claim 1

In an automatic colorimetric analyzer, the combination of, a housing, a pair of hollow transparent cylinders in said housing, a pair of pistons mounted for reciprocation in respective ones of said cylinders, said housing having light transmitting passages extending to and through said cylinders in regions periodically blocked by said pistons as they reciprocate, said pistons having central passages for transmitting fluid paths, and from said cylinders, said passages being at the top of said cylinders and thus defining air bubble escape path, means including said passages for conveying fluid in a stream from a sample source to first one cylinder and then the other cylinder, valves for selectively blocking said stream between said source and the first cylinder, between said cylinders, and downstream of said second cylinder, a light system including a single lamp and a single photocell for passing and sensing light beams through said cylinders, means for adding a reagent to said sample stream between said cylinders, and means for alternately reciprocating said pistons and operating said valves so as to pump said stream at a uniform measured incremental rate, wipe said cylinders clean, and permit alternate sensing of light beams passing through said cylinders.

Claim 5

The method of automatically analyzing turbid water colorimetrically comprising the steps of directing two beams of light of the same intensity and wave lengths to respective ones of two transparent cells and toward a light sensor, introducing successive samples of the water under test to one of said cells, directing said samples successively from said one cell to the other cell, adding a test reagent to the sample while it is being directed from said one cell to said other cell, alternately blocking said light beam so as to cause said light sensor to read alternately said beams, comparing said sensor reading so as to detect any difference caused by a color change in the combined sample-reagent, and adding a solution to said water samples before they are introduced to said one cell, said solution having the same effect on turbidity as could later be expected from said reagent.

Claim 6

The method of automatically analyzing turbid water colorimetrically comprising the steps of directing two beams of light of the same intensity and wave lengths to respective ones of two transparent cells and toward a light sensor, introducing successive samples of the water under test to one of said cells, directing said samples successively from said one cell to the other cell, adding a test reagent to the sample while it is being directed from said one cell to said other cell, alternately blocking said light beam so as to cause said light sensor to read alternately said beams, comparing said sensor reading so as to detect any difference caused by a color change in the combined sample-reagent, and adding a solution to said water samples before they are introduced to said one cell, said solution having the same effect on turbidity as could later be expected from said reagent.