| 摘要 |
<p>PURPOSE:To keep the freshness of a material stored in a storage chamber by predicting the change of the oxygen concentration in the chamber and supply ing a proper amount of oxygen. CONSTITUTION:The O2 concentration in a storage chamber 1 is determined by an O2 sensor 2. Air or N2 gas generated by a gas-feeding unit 4 is supplied to the storage chamber 1 by a controlling circuit 3 based on the detection signal transmitted from the O2 sensor 2 to keep the O2 concentration in the chamber to 0<=O2<=1%. When the O2 concentration is <=0.5%, the controlling circuit 3 predicts the variation of the O2 concentration after a prescribed period based on the measured values of O2 concentration detected at regular intervals and starts the supply of N2 gas to the chamber.</p> |
