Abstract: In an apparatus for fluid analysis, a plurality of reagent-mixture components are each injected by a respective pump through a valve matrix and into a flow-injection unit. The flow-injection unit defines a mixing chamber including a plurality of. As the reagent-mixture components are injected into the mixing chamber, the nubs agitate the fluid flow, thereby dispersing the reagent-mixture components and in turn mixing the components together to create a reagent mixture. The flow rates of the reagent-mixture components are adjusted in order to select the reagent-mixture ratio as the components are combined in the flow-injection unit to thereby create the selected reagent mixture. Upon passage through the flow-injection unit, the reagent-mixture is injected into a sensing unit for analyzing a particle distribution of the mixture.

Abstract: In an apparatus for fluid analysis, such as hematologic analysis, a plurality of reagent-mixture components are each injected by a respective pump through a valve matrix and into a flow-injection unit. The flow-injection unit defines a mixing chamber including a plurality of protuberances or nubs projecting inwardly toward the center of the chamber, and spaced relative to each other both axially and radially. As the reagent-mixture components are injected into the mixing chamber, the nubs agitate the fluid flow and create turbulence, thereby dispersing the reagent-mixture components and in turn mixing the components together to create a reagent mixture. The flow rates of the reagent-mixture components are adjusted in order to select the reagent-mixture ratio as the components are combined in the flow-injection unit to thereby create the selected reagent mixture.

Abstract: In a valve assembly exhibiting zero dead volume the port head is mounted on a solenoid and defines an inlet port on one side of the valve seat, and two outlet ports on the opposite side of the valve seat. A flexible diaphragm is seated across the valve seat between the port head and the solenoid, and is sealed along its peripheral edge. A spring-biased valve rod is coupled to the opposite side of the diaphragm relative to the valve seat, and the solenoid is actuated to move the valve rod and diaphragm between open and closed positions. The valve assembly is opened by actuating the solenoid to drive the valve rod and diaphragm away from the valve seat and permit the passage of fluid across the valve seat between the inlet and outlet ports.