| 摘要 |
PURPOSE:To simplify a constitution and reduce a generation of air blowing sound by a method wherein a symmetrical line of a filter member having a filter element integrally arranged in a frame is set at a position displaced from a center of a fan. CONSTITUTION:A filter member be constituted of a frame 4 having a grid member 8 integrally formed therewith and a filter element 5 installed at a rear surface. A filter member to be installed at a front panel 3 is constructed in such a way as a symmetrical line A-A of the grid 8 is placed at a position displaced in respect to a center of a fan 2. As a result, a plurality of vanes of a rotating fan 2 may not cross simultaneously some ribs constituting the grid 8, reduce a noisy air blowing sound and thus a silent ventilating operation can be realized. Even if the symmetrical line A-A of the grid 8 is displaced from a center of the fan 2, the fan 2 is hidden through installation of the filter member, so that no irregular outer appearance is generated. |
