Method to operate film leak tester; involves using form test chamber, which is evacuated using one pump, before testing using second vacuum pump and taking ambient helium concentration into account

摘要

The method involves using a tester with a film (5,6) extended in each of two frames (3,4) to form a test chamber for an item to be tested, and two vacuum pumps (13,30) to evacuate the test chamber before testing for leaks. During a first evacuation phase, only one vacuum pump is used and during leak testing only the second vacuum pump is used. The ambient helium concentration is measured before testing and used to correct the leak measurement. An Independent claim is included for a film leak tester for implementing the method.