Device for injecting a fixed quantity of liquid

摘要

A device for injecting a fixed quantity of sample liquid is provided with a unit for aspirating and injecting sample liquid. The sample aspirating and injection unit has a nozzle connecting portion. The liquid injection device is provided with an injection nozzle attached to and detachable from the nozzle connecting portion of the sample aspirating and injecting unit and electrodes are attached to the injection nozzle. Conductive members which are electrically connected to the electrodes of the injection nozzle are attached to the nozzle connecting portion of the sample aspirating and injecting unit, and a detecting unit which cooperates with the electrodes to detect the surface level of sample liquid is connected to the conductive members.