| 摘要 |
PURPOSE:To reduce a load on an air filter for an internal chamber, thereby to make the filter small in size, to use an air filter for an intermediate space for a long period and thereby to improve the effect of use by separating air cleaning in the internal chamber from air cleaning in the internal space. CONSTITUTION:Air in an internal chamber 11 passes through an exhaust port 14 and flows into an air cleaner 13 and a detrimental gas component in the air is filtered by a filter 13a. The air cleaned by the filter 13a is supplied into the internal chamber 11 through a cleaned air outlet 12. In the meantime, air in an intermediate space C passes through an exhaust port 16 and flows into an air cleaner 17 and the detrimental gas component in the air is filtered by a filter 17a and then supplied into the intermediate space C through a cleaned air outlet 15. According to this constitution, a filtering operation for the detrimental gas component in the air in the internal chamber 11 is executed by the cleaner 13, while the filtering operation for the detrimental gas component in the air in the intermediate space C is executed by the cleaner 17, and thus the cleaning operation for the air in the internal chamber 11 and that for the air in the intermediate space C are executed separately. |
