| 摘要 |
PURPOSE:To extend a sweep time in the same inspection time, and to make a sweep without stopping the device by providing a changeover valve to test piping closer to a mass analyzer side than its connection part for sweep piping and in the middle of the conduit of the sweep piping respectively. CONSTITUTION:An object of inspection is put in bell jars 1a and 1b, which are evacuated and charged uniformly with helium gas. When the bell jar 1a is tested, a valve 5a and a changeover valve 17 are closed and a sweep changeover valve 22 and a changeover valve 18 are closed. Further, a valve 5b and a sweep changeover valve 23 are opened so as to sweep test piping 120 and sweep piping 21. In this state, a test piping 110 uses a cycle fully for a test process and the test piping 120 uses a cycle fully for a sweep process. Then, when the bell jar 1b is tested in the next cycle, respective valves are all operated reversely. Consequently, the bell jars 1a and 1b are tested or swept at any time and never suspended. Therefore, the time for testing and sweeping is extended in the same cycle. |
