Patent ID: 7987698

Claim:
A gas leak detection apparatus, comprising: a flow volume measurement means for measuring the instantaneous flow volume of gas flowing inside a gas flow channel; a instantaneous flow volume time differential operation means for operating the time differential value of the instantaneous flow volume which has been measured by the flow volume measurement means; a characteristics extraction means for extracting the characteristics of the gas flow including a region data in which a plurality of combinations of the instantaneous flow volume and the time differential value of the instantaneous flow volume are plotted on a two-dimensional graph, on the basis of the instantaneous flow volume which has been measured by the flow volume measurement means and the time differential value of the instantaneous flow volume which has been operated by the instantaneous flow volume time differential operation means; a storage means for registering characteristics data that includes the region data indicating different gas flow characteristics for respective types of gas appliance or for a gas leak; a characteristics data registration means for registering in the storage means characteristics data that includes the region data indicating characteristics which have been extracted by the characteristics extraction means from a flow volume pattern in which the occurrence of a flow volume has been measured by the flow volume measurement means and the flow volume has subsequently become zero; and a leak detection means for performing leak detection in which the presence or absence of a gas leak is judged, and outputting a judgment result, by comparing the characteristics data which has been registered in the storage means with the characteristics of the gas flow which has been extracted by the characteristics extraction means; wherein the leak detection means compares the region data of the characteristics data which has been registered in the storage means with the region data of the characteristics of the gas flow which has been extracted by the characteristics extraction means, judges as to whether there is a characteristics data that matches the region data of the extracted characteristics on the gas flow, and if there is no characteristics data that satisfies the matching, judges the level of a measured value or an operated value included in the characteristics of the extracted characteristics on the gas flow to judge as to whether there is a gas leak, and wherein the characteristics data registration means registers the characteristics of the gas flow forming the basis of a judgment as new characteristics data, in the storage means, when it has been judged by the leak detection means that there is no gas leak as a result of the level judgment performed by the leak detection means.