| 摘要 |
<p>1499424 Fan intake silencers TATRA NARODNI PODNIK 22 May 1975 [12 July 1974] 22338/75 Heading FIB The intake duct 1 of a cooling fan 4 for an I.C. engine has a lining 9 of sound absorbing material and is curved so that a line joining the edge 7 of the mouth of the duct to a point 6 on the periphery of the fan housing, is tangential to the inner surface 5 of the opposite wall of the duct. In a first modification, Fig. 2 the duct is bifurcated and each branch is curved. In a second modification, Fig. 3 (not shown), guide vanes (19, 20, 21, 22) are provided in the duct and extend from wall to wall. The leading and trailing edges of adjacent vanes are tangential to lines drawn from a point on the periphery of the housing and passing out through the mouth of the duct. In a third modification, Fig. 5 (not shown) the duct is barrel-shaped as seen in one plane including the axis of the fan and includes curved plates (39, 40, 42, 43) lined with soundabsorbing material and a central member (41). Lines joining the upstream and downstream edges of the curved plates are tangential to the surface of the adjacent member.</p> |
