Apparatus for determining hemoglobin and white blood cell count in blood

摘要

A single instrument for photometrically determining hemoglobin content and electronically determining white blood cell count of a single sample suspension of blood. The instrument is provided with a calibration mode of operation independent of the run or normal operational mode of the instrument. A vacuum system is described where vacuum is generated during the operating cycle only at periods when vacuum is required with an adjustable volume vacuum chamber interposed in the vacuum system to assure proper vacuum levels. Carryover of one liquid to a next introduced second liquid in the test vessel is reduced by successive draining of said second liquid and reintroduction into said vessel of a replacement amount of said second liquid. The second liquid can be a sample of rinse liquid. An hydraulic system is described as operating in conjunction with the pneumatic or vacuum system. The hydraulic system employs additional plural solenoid operated devices, each to perform a specific operational function during the operational cycle of the instrument.