| 摘要 |
<p><P>PROBLEM TO BE SOLVED: To appropriately secure a use restriction function of an apparatus having variable gas use quantity. <P>SOLUTION: This gas cutoff system comprises a flow rate detection means 10; a flow rate calculation means 11; an average flow rate calculation means 12; a flow rate storage means 14 for storing an average flow rate value; a flow rate change determination means 14 for determining whether or not a flow rate is changed; a flow rate registration means 15 for registering a flow rate change amount or deleting a registered flow rate near to the flow rate change amount when increase/decrease of the flow rate is determined by the flow rate change determination means 14; a flow rate memory means 16; a flow rate change correction memory means 17 for determining whether or not a total registered flow rate deleted in the past and an average flow rate are within a predetermined range, when flow rate change is determined by the flow rate change determination means 14 and only a maximum flow rate is registered; a determination period means 18 for deleting and reregistering the flow rate of the flow rate memory means 16 and the registered flow rate, when it is determined that the flow rate is not changed for a predetermined period; a monitoring value memory means 19; an abnormality determination means 20 for comparing the flow rate value of the flow rate registration means 15 with the determination value of the monitoring value memory means 19 to determine whether or not an abnormality occurs; and a use time correction means 22 for outputting a correction signal when reregistration is performed by the determination period means 18. <P>COPYRIGHT: (C)2009,JPO&INPIT</p> |
