US 4,250,553 A · Fluid flow measurement system

Abstract

An oxidant flow conduit having a restriction and branching downstream of the restriction to provide a primary flow conduit for supplying oxidant to a nebulizer and an auxiliary flow conduit having an adjustable valve for supplying oxidant to a mixing chamber is provided. A differential pressure transducer measures the pressure drop across the restriction to provide an output signal. A primary fuel conduit is provided having a pair of restrictions with an adjustable valve for supplying fuel to the mixing chamber. A boost conduit having a restriction is connected to the primary fuel conduit and between the restrictions providing for supplementing the fuel to the mixing chamber when a different fuel mixture is used. A differential pressure transducer measures the pressure drop across the pair of restrictions to provide an output signal. A square root linearization operation is performed on each signal in a microprocessor and modified output signals drive respective fuel and oxidant digital displays. Consequently, increased and substantially identical sensitivity to adjustment and attainment of normal flame conditions are achieved when switching between boosted and non-boosted fuel flow.

Claims5

Dependent claims

A fluid measuring and control system for the burner in atomic spectroscopy comprising:

a fluid flow conduit having an inlet port and an outlet port for transmitting fluid under pressure from said inlet port to said outlet port;
a first restriction in said fluid flow conduit providing a pressure drop thereacross;
a second restriction in said fluid flow conduit downstream of said first restriction;
a boost conduit in communication with said fluid flow conduit at a location therealong between said first restriction and said second restriction and lying in communication with said outlet port, said boost conduit having a third restriction therein;
a sensor for sensing the pressure drop across said first and said second restrictors and providing an output signal proportional to said pressure drop;
means operable on said signal for providing a substantially linear indication of said pressure drop as a function of the rate of flow of the fluid through said conduit;
means in said flow conduit downstream of said first and said second restrictions for adjusting the flow through said conduit to a predetermined flow in accordance with said indication;
and
means for enabling flow through said fluid flow conduit and said boost conduit simultaneously.

6 more elements

Dependencies are inferred from the claim text.

Fluid flow measurement system

Life of this patent

Fluid flow measurement system

Life of this patent

Abstract

Claims5