Document Type and Number:
Japanese Patent JPS4971335
Kind Code:
A
Abstract:
A shroud enclosing an automotive type fan has ridges projecting from the internal surface equally spaced circumferentially to provide a circumferentially undulating pattern to the axial flow of air forced through the space between the shroud and the fan to reduce the noise level of the shroud-fan combination.
Application Number:
JP11104873A
Publication Date:
July 10, 1974
Filing Date:
October 04, 1973
Export Citation:
International Classes:
F04D29/54; F01P11/10; (IPC1-7): F04D29/40