AUTOMATIC SAMPLE TESTING MACHINE

An automatic sample testing machine for testing samples stored in test cards . The machine has a test sample positioning system for moving a tray containing a plurality of test sample cards and fluid receptacles among various stations in the machine. Th e machine has a diluting station for adding a predetermined quantity of diluent to the receptacles as needed. A pipetting station transfers fluid from one receptacle to another. A vacuum station is provided having a vacuum chamber moveable relative to the tray between upper and lower positions. The chamber cooperates with the tray to make a sealing engagement with the top surface of the tray when it is lowered to the lower position. A vacu um generator supplies vacuum to the chamber. When the vacuum is released from the chamber , the fluid samples are loaded into the cards from the receptacles. The test sample positioning system moves the tray to a cutting and sealing station and then to an incubation station and loads the cards one at a time into a carousel within the incubation station. A tes t card transport station transports the test cards from the incubation station to an optical reading station, where optical measurements (e.g., transmittance and/or fluorescence optical testing) is conducted on the wells of the card. When the card has been read, it is eithe r moved back to the incubation station for additional incubation and reading or transferred to a stacking card disposal system when the reading is complete.