| 摘要 |
There is disclosed an instrument probe assembly that is suited for the measurement of a variable of a flowing liquid stream which contains suspension of debris and foreign matter. The instrument probe assembly includes a housing having a closed end for immersion in the liquid with a concavity in the closed lower end having sidewalls inclined at an acute angle to the longitudinal axis of the housing and at least one through opening in a sidewall of the concavity to receive at least one probe member which is sensitive to a variable of the liquid with its exposed surface generally continuous with the sidewall. The probe member assembly is employed with a pH meter that includes a sensing electrode in the concavity with the reference electrode mounted within an annular chamber of the housing and having the reference electrolyte in contact with the liquid through a porous disk which is mounted in the through opening in the sidewall of the concavity. The resultant assembly is ideally suited for measurements of a flowing liquid stream that contains debris and foreign suspended matter, e.g., process streams of a sewage plant, since the concavity of the probe assembly introduces a circulatory motion to the liquid within the concavity and this motion prevents the accumulation of debris and foreign matter about the surfaces of the sensing electrode and reference junction of the cell. |
