| abstract |
An apparatus for automatically performing a series of operations on a blood sample contained in a vial. For example, in performing the Coombs antiglobulin test, the apparatus is programed to initially inject saline into the vial, to centrifuge the vial at approximately 1,300 RCF, and then to decant the saline from the vial leaving a ''''button'''' of blood cells in the vial. The above sequence is repeated three times, and then a predetermined amount of Coombs serum is injected into the vial. The vial is then agitated to mix the serum with the blood cells, and then it is centrifuged at 500 RCF. At the termination of the centrifuging operation, the sample will be ready for final analysis by a technician. In carrying out this invention, a circular turntable is provided having a plurality of receptacles positioned about its outer periphery. Each of the receptacles is adapted to receive a single vial and includes a pivotally mounted flag which is lifted to a horizontal position whenever a vial is present. An electrical motor is provided to rotate the turntable, and a dispensing mechanism overlies the periphery of the turntable and includes a nozzle for injecting the saline as well as a nozzle for injecting the Coombs serum downwardly into the vial. A photoelectric mechanism is provided for detecting a horizontal flag which then actuates the appropriate injection mechanism. The Coombs injecting mechanism includes a removable cartridge containing the serum. The cartridge comprises a tubular barrel which is closed at its forward end by a nozzle and at its rear end by a cylindrical piston positioned within the bore of the barrel. The mechanism further includes a plunger for driving the piston into the bore of the barrel to dispense the liquid from the forward nozzle. |