摘要 |
A gas transfer unit includes a transfer path forming member; a gas transferring member; and a gas purifying member as defined herein, and in a case where exhaustion is performed through the first exhaust port, the transfer vanes are rotated at a first rotation number, and, in a case where exhaustion is performed through the second exhaust port, the transfer vanes are rotated at a second rotation number which is higher than the first rotation number.
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