Method for detecting fault in leakage inspector, leakage inspector

摘要

In a calibration step, air is sealed in a first device serving as a reference device; a pressure change B 1 in the first device at a point elapsed a predetermined period of time from the air sealing, and a pressure change B2 at a point further elapsed the predetermined period of time are measured; and these pressure changes are stored. In an inspection step, air is sealed in a second device to be checked for a leak; pressure changes B1' and B2' corresponding to the pressure changes B1 and B2 are measured after the air sealing; and a waveform ratio K is calculated from these measured values as (B 1' - B2')/(B 1 - B2). It is decided whether a malfunction occurs in a leakage inspector by using the value of the waveform ratio K.