Patent ID: 9551626
Date: 2017-01-24
CPC Classifications: G01M

Claim:
1. A leak testing method for performing a leak test of a workpiece including a first space, a second space and a third space which are three partitioned void portions, and being likely to include a first external connection route which connects the first space to the outside, a second external connection route which connects the second space to the outside, a third external connection route which connects the third space to the outside, a first internal connection route which connects the first space and the second space, a second internal connection route which connects the second space and the third space, and a third internal connection route which connects the third space and the first space, the leak testing method comprising: a first step of injecting a gas to the first space at a predetermined pressure, and obtaining a first total leakage amount which is a total amount of the gas leaking from the first internal connection route, the third internal connection route and the first external connection route; a second step of injecting the gas to the second space at a predetermined pressure, and obtaining a second total leakage amount which is a total amount of the gas leaking from the first internal connection route, the second internal connection route and the second external connection route; a third step of injecting the gas to the third space at a predetermined pressure, and obtaining a third total leakage amount which is a total amount of the gas leaking from the second internal connection route, the third internal connection route and the third external connection route; a fourth step of injecting the gas to the first space, the second space and the third space at a predetermined pressure, and obtaining a fourth total leakage amount which is a total amount of the gas leaking from the first external connection route, the second external connection route and the third external connection route; a fifth step of injecting the gas to the first space and the third space at a predetermined pressure, and obtaining a fifth total leakage amount which is a total amount of the gas leaking from the first external connection route, the third external connection route, the first internal connection route and the second internal connection route; a sixth step of injecting the gas to the first space and the second space at a predetermined pressure, and obtaining a sixth total leakage amount which is a total amount of the gas leaking from the first external connection route, the second external connection route, the second internal connection route and the third internal connection route; a step of calculating, based on the obtained first to sixth total leakage amounts, first to sixth leakage amounts which are amounts of leakage from the first external connection route, the second external connection route, the third external connection route, the first internal connection route, the second internal connection route and the third internal connection route respectively when the gas is injected to the workpiece at a predetermined pressure; and a step of determining whether the workpiece is normal or defective based on the calculated first to sixth leakage amounts.