Measuring and testing – Sampler – sample handling – etc. – Automatic control
Patent
1993-07-09
1996-02-27
Noland, Thomas P.
Measuring and testing
Sampler, sample handling, etc.
Automatic control
7386301, 7386311, 7386385, 7386425, 73304C, 340620, 137392, G01F 2326, G05D 912, G01N 3510, G01N 110
Patent
active
054939224
ABSTRACT:
A method and apparatus for a liquid level sensor control circuit of a bioassay apparatus for controlling a position of a sampling probe with respect to a surface of a liquid in a container. The apparatus includes a sampling probe, an oscillator circuit coupled to the sampling probe for producing a first output signal having a constant frequency, a comparator coupled to the oscillator circuit for comparing the amplitude of the first output signal to a first reference amplitude and for producing a change signal when the amplitude of the first output signal changes with respect to the reference amplitude, and a controller responsive to the change signal for controlling the position of the sampling probe with respect to the surface of the liquid.
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Moreno Mario
Ramey B. Edward
Akzo N.V.
Blackstone William M.
Muir Gregory R.
Noland Thomas P.
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