Multiple trough vessel for automated liquid handling apparatus

Claim 1

In a machine for automatically transferring at least a portion of a liquid supply to one row of wells to fill or mix with liquid samples in said one row or with another row of wells which includes: a head assembly translatable between upper and lower positions along a vertical axis; means for moving said head assembly along said vertical axis; and a plunger assembly mounted on said head assembly for movement therewith, said plunger assembly including a row of pipette nozzles, each having a depending end to receive a tip, a row of plungers respectively disposed within said pipette nozzle, and means for moving said plungers within said pipette nozzles to vary their internal volumes to aspirate liquid into or discharge liquid from said tips, the combination of a table mounted beneath said head for translation along a horizontal bed, said table having a plurality of work stations spaced along said bed for respectively accommodating at least one row of a plurality of rows of wells in at least one tray at each of said work stations and a vessel having a plurality of troughs parallel to said plurality of rows of wells to accommodate a second plurality of said work stations; means for moving said table along said horizontal bed selectively to place any one of said rows of wells in said at least one tray or one of said plurality of troughs at said work stations in register with said pipettes, means for controlling each of said moving means for said head assembly, plungers and said table to effect liquid transfer between said one trough and said one row of wells in a tray at said work stations, and receptacle means for storing a plurality of rows of replaceable tips for the ends of said pipettes nozzles at a third plurality of work stations on said table to permit disposal and replacement of said tips on said depending ends of said pipette nozzles with other tips disposed in at least some of the receptacles of said receptacle means between predetermined steps of a liquid transfer process.