Patent ID: 7121368

Claim:
In a vehicle having a front engine bay with an engine located therein, a radiator having a coolant circulating therein, and an axial flow cooling fan for circulating air through said radiator; the improvement comprising: a motor operative to drive said axial flow cooling fan in both a forward and a reverse direction, said forward direction being one wherein said fan blows air from said radiator through said engine bay; temperature sensing means for measuring the temperature of said coolant and to provide a temperature signal responsive thereto; vehicle speed sensing means for measuring the speed of the vehicle and to provide a vehicle speed signal; and a control circuit to receive said temperature signal and said vehicle speed signal and to control the direction of operation of said axial flow cooling fan in response to said signals, said control circuit being operative to cause said fan to operate in a reverse direction when said vehicle is moving above a predetermined speed and said temperature is below a first preset level; said control circuit also being operative to cause said fan to operate in a reverse direction when said vehicle is moving below a predetermined speed and said temperature is above a second preset level.