摘要 |
<p>The present invention is directed to the implementation of a multi-port rotary valve in an automated chemistry processing instrument which reduces chemical reagent cross contamination and simplifies system design and control. One or more multi-port rotary valves are used in conjunction with isolation valves which are each dedicated for an associated reagent in the system. According to one embodiment of the present invention, the instrument utilizes a multi-port valve which defines several fluid branches each associated with a reagent. The valve has a common inlet and common outlet which are selectively brought into fluid communication with the branches in a controlled sequence. At each branch, there is a two-way three-port isolation valve which controls introduction of an associated reagent into the branch. When a branch is selected by the rotary valve, the reagent introduced into the branch is delivered out of the common outlet by the flow from the common inlet. According to another embodiment of the present invention, the reagents are introduced through isolation valves between two multi-port rotary valves.</p> |