Electric fan for vehicle heating or air-conditioning system

摘要

An electric motor has an opening in the casing near the commutator with a non-return valve (22) to allow the entry of cooling air, but not in the reverse direction. The valve is either flush with the casing or mounted in a short tube projecting from it. The valve is a rubber flap held at one edge on the inside. The fan wheel on the rotor shaft has a hollow cap (17) as a hub for the blades (19), and at the back of the cap, facing the motor, are short blades (20) which create reduced pressure to support the cooling air stream.