| 摘要 |
PROBLEM TO BE SOLVED: To carry out a minute leakage test rapidly and accurately by measuring changes in negative pressure in consideration of a portion of a container which is assembled with parts and causes a microleakage. SOLUTION: In the method, a sealing section 5 of a test head 4 is attached to the container 1 so as to cover a welded section 3 of the container 1. The container 1 is sealed after supplying air with a pressure nearly equivalent to an actually used pressure. The air in a pressure change measuring space 6 is vacuumed up in the arrow direction of the figure by a vacuum pump (not shown), thereby making a negative pressure state, e.g. about 100mmHg (133.3×10<SP>2</SP>Pa), in the pressure change measuring space 6. After stopping the vacuum pump, the negative pressure of the pressure change measuring space 6 is measured by a negative pressure-type air tester for several seconds for example. In the case change values of the negative pressure are not more than a prescribed value, it is judged that no leakage is present at the welded section 3. The volume of the pressure change measuring space 6 is about several percentages of that of the container 1. Therefore, the leakage test of the container 1 is carried out very rapidly and is hard to be affected by temperature changes because of the negative pressure. COPYRIGHT: (C)2004,JPO
|
