Abstract: Method of cooling a heat exchanger of an engine using a cooling fan system includes: measuring conditions of an engine cooling system, determining a desired fan cooling demand. Based on the fan cooling demand, a fan control circuit operates to selectively control an electrically commutated (EC) motor at a continuously variable speed for an EC cooling fan and to control a direct current (DC) motor of a DC cooling fan. The DC motor is controlled to: not operate the DC cooling fan, operate the DC motor at a first predetermined operating speed, and operate the DC motor at a second predetermined operating speed corresponding to a second DC motor speed signal that is less than the first predetermined operating speed. The conditions for determining fan cooling demand include at least one of a temperature and a pressure of an engine coolant and of a refrigerant of a vehicle air conditioning system.

Abstract: An assembly for increasing air flow to a vehicle cooling system includes a portion of a cooling fan shroud, the portion having a face defining an opening therethrough, and a plurality of support members extending from the face. A flap includes a plurality of apertures proximal to an edge. Each aperture of the plurality of apertures is formed to receive one of the plurality of support members for coupling the flap thereto. A clearance fit formed between the apertures and the support members permits movement of the flap from a first position generally parallel to the face to a second position in response to a flow of air.

Abstract: An improved plastic, injection-molded shroud/banded fan combination in which the shroud extends axially from an inlet portion to an outlet portion, and the outlet portion comprises means for connecting a heat exchanger to the shroud, More specifically, the shroud includes an inlet lip which is curved in cross-section and positioned at the inlet portion of the shroud. The lip extends radially inward and axially downstream from the inlet portion of the shroud to a trailing edge. An intermediate cylindrical wall is attached to said inlet lip. The intermediate cylindrical wall is positioned: 1) coaxially with the fan; and 2) radially between the inner surface of the shroud and portions of the outer surface of the fan band so as to form a wall-to-band radially restrictive running clearance.