Tandem fan arrangement e.g. for motor vehicle air-conditioning system

摘要

One of the two impellers (3) is powered off the motor shaft (10) through a viscous fluid coupling (7,11), with overriding freewheel units (18) between coupling and belt pulley (12) and electric motor drive shaft (17) and associated pulley. The electric motor (16) is allocated to impeller (4), so the second impeller is driven through the coupling. The belt (13) is led over a tension roller here designed as a belt pulley driven by the electric motor and is preferably arranged outside the impeller diameter area. The viscous coupling (7,8,11) is driven off the engine shaft (10) via a flexible coupling (8), with the electric motor (16) and the viscous coupling fixedly located on the engine shaft and the impeller (fan) vanes assigned to a movably mounted cooler frame. The rating of the electric motor is thus suitable for extended running off the onboard mains. The coupling housing (11) mounts the pulley (12) for the toothed belt (13) running to the second pulley (14) allocated to the impeller (4) hub (15), with freewheel (18) fitted in between the electric motor (16) shaft (17) and pulley (14).