| 摘要 |
A liquid sampling apparatus which is capable of correctly detecting whether or not a suction nozzle sucks a predetermined amount of a liquid sample. A electrostatic capacitance measuring unit 51 measures a electrostatic capacitance Cx between electrodes 24 and 25 when the nozzle 26 is placed at the highest position, and an abnormal suction detection unit 53 determines whether the measured electrostatic capacitance value Cx is less than a electrostatic capacitance value Ca. If Cx<Ca stands, the detection unit 53 determines that the vessel 23 is empty, and supplies a computer 3 with an abnormal indicating signal. If Cx>/=Ca stands, the detection unit 53 stores the detected Cx as the electrostatic capacitance value Ca. As the nozzle 26 is being moved down, the measuring unit 51 measures the electrostatic capacitance Cx, and the liquid surface detection unit 52 determines whether Cx is larger than a predetermined value. The nozzle 26 is moved down until Cx becomes larger than the predetermined value. Once Cx is determined to be larger than the predetermined value, the nozzle 26 is stopped to suck a liquid sample, and is again moved upward. The measuring unit 51 measures the electrostatic capacitance Cx to determine whether it is smaller than Ca-Cb. If Cx>Ca-Cb stands, the measuring unit 51 determines abnormal suction and supplies the computer 3 with an abnormal indicating signal. <MATH> |
