| 摘要 |
PURPOSE:To securely obtain a clean space with a height necessary for an operation and contrive a reduction in blowing power, by blowing off clean air from the upper par of a blow-off port in an obliquely upward direction, while blowing off clean air from a lower part of the blow-off port substantially horizontally. CONSTITUTION:A blower 10, a filter 12, a suction port 14 and a blow-off port 16 are provided. The blower 10 and the filter 12 are disposed in a duct 18, while the suction port 14 and the blow-off port 16 are disposed respectively at an inlet part and an outlet part of the duct 18. The blow-off port 16 is divided into an upper blow-off port 16a for blowing off clean air obliquely upward and a lower blow-off port 16b for blowing off clean air horizontally. The clean air blown off skewly upward from the upper blow-off port 16a shields polluted air. The clean air blown off horizontally from the lower blow-off port 16b securely provides a clean space with a height (100-200mm), from an operating surface, necessary for the operation over the entire operating surface, under the condition where air is not polluted from the upper side. |
