| 摘要 |
PROBLEM TO BE SOLVED: To detect the presence or absence of a structural defect of one or more stacked permeable membranes of a body under test such as a fuel cell with a helium leak detector in a short time with high sensitivity. SOLUTION: A fixed quantity of a gas other than helium is continuously fed to a gas flow passage 5 in advance. When helium is guided into the permeable membrane 1 through a helium guide passage 3, helium permeates from the peripheral wall section of the permeable membrane 1 to the flow passage side and reaches a sniffer probe 6 after a fixed time elapses, thereby the sniffer probe 6 detects a fixed quantity of saturated helium. If the permeable membrane 1 has a structural defect such as a pinhole, helium flows out to the gas flow passage 3 side through the structural defect portion and reaches the sniffer probe 6 before it permeates the peripheral wall section. |
