| 摘要 |
PROBLEM TO BE SOLVED: To control the concentration of oxygen in a sterilizing booth, to reduce the danger of fire occurrence under high concentration and further to prevent adverse influences upon a human body. SOLUTION: The time from the open of a solenoid valve for oxygen in a start mode to the close is set in limit value setting processing (step 202). In this limit value setting processing, the capacity of the sterilizing booth is read and based on a transform table or a transform formula preset from that capacity, the opening time is found suitably for the concentration of oxygen allowable in the sterilizing booth having the relevant capacity. Then, when it is discriminated the solenoid valve for oxygen is opened for prescribed time set by the step 202 (step 220), the solenoid valve for oxygen is closed (step 230) so that the concentration of oxygen can be prevented from rising in a space to be sterilized because of unwanted opening. |
