| 摘要 |
PURPOSE:To permit to prevent an air flowing in from outside through a gap between a pipe penetrating hole and a pipe, even if the above gap is generated by a method wherein an outlet is provided nearby a grating in a suction side, also a penetrating hole for passing through a piping is provided between the above outlet and a pre-filter and inside the outlet, a window direction control plate is also provided. CONSTITUTION:An air-stream is passing through a pre-filter 4, sucked up by a fan-motor 3, then passing through another pre-filter 7 and flowing into a duct 9. A partial air flow discharging from the outlet 6 in the duct 9, is reflecting its flow direction toward the pre-filter 7 by the use of the wind direction of the upper part of the pre-filter 7 by the use of the wind direction control plate 10, free adjustable in an angle, thereby, the air is flowing out of the gap between a space the piping and the penetrating hole 5 and the air is blown off. Therefore, the outside polluted air coming in through the gap into the duct 9 is prevented, thereby, a deterioration of air purity as well as generation of a turbulence flow in the duct 9 are eliminated. The wind direction control plate 10 consists of a rectangular shaped board and a bar for a screen, very simple in producing and also an inclined angle is freely variable. |
