METERING DEVICE WITH DEFINED ENABLED FLOW DIRECTION

摘要

A sample injector (40) configured to introduce a sample fluid into a mobile phase, wherein the mobile phase is to be driven by a mobile phase drive (20) through a separation unit (30) for separating compounds of the sample fluid in the mobile phase, wherein the sample injector (40) comprises a metering device (200) being operable for displacing fluid and for intaking a metered amount of the sample fluid into the sample injector (40), an injector valve (90) being switchable for operating the sample injector (40) selectively in a sample intake mode in which the metering device (200) is operable to intake the sample fluid from a sample container (500), or a separation mode in which intaken sample fluid is driven between the mobile phase drive (20) and the separation unit (30) for separating the compounds, and a flow direction controller (202) configured for defining an enabled flow direction of fluid displaced by the metering device (200) and for defining a disabled flow direction.