| 摘要 |
PURPOSE:To improve an assemblying characteristics or an accuracy in size with a simple structure and further improve an aerodynamic performance or an effect of reducing noise by a method wherein a centrifugal fan device is disposed such that a fan suction port is faced against a device suction port and outer walls are substantially abutted against the right and left side surfaces of a casing with a hard porous structure. CONSTITUTION:Since a fan suction port 16 is disposed to face against a device suction port 2, there is no increased noise caused by a disturbed flow sucked into the fan. The device is made such that it has a hard porous outer wall 10 of which size is increased up to its full width size under a severe dimensional restriction (i.e., substantially abutting against the inner surface of the case) and further its outside part is provided with a rear surface air layer 17 utilizing a dead space, resulting in that an aerodynamic performance is superior and a noise reducing effect can be excessively high. In addition, the hard porous outer wall 10 can be easily pressed by only the outer wall edge holding part 13 and a fan device lower partition plate 14, so that its structure is quite simple and its assemblying performance or accuracy in size can be excessively improved. |
