Patent ID: 8668435

Claim:
A fan ( 100 ), selected from the group consisting of an axial fan and a diagonal fan, having a fan housing ( 110 ) that comprises: an air entrance opening ( 120 ); an air exit opening ( 130 ); a swivel joint arrangement ( 180 ) having at least one swivel joint ( 145 , 147 , 155 , 157 , 165 , 167 , 175 , 177 ) that is arranged on a joint carrier ( 188 ; 188 ′); at least one non-return flap ( 140 , 150 , 160 , 170 ) that is journaled rotatably by means of the at least one swivel joint ( 145 , 147 , 155 , 157 , 165 , 167 , 175 , 177 ) and, in a closed orientation, at least partly closes off the air exit opening ( 130 ); at least one elastic return member ( 142 , 152 , 162 , 172 ), that is arranged between the non-return flap ( 140 , 150 , 160 , 170 ) and joint carrier ( 188 ; 188 ′), and is mounted on the non-return flap and abuts slidingly with a preload against the joint carrier ( 188 ; 188 ′), and thereby urges said non-return flap ( 140 , 150 , 160 , 170 ) in a closing direction.