Control box for a motor vehicle engine cooling system

Claim 1

Cooling apparatus for a motor vehicle engine, comprising: a heat exchanger for air cooling of a coolant fluid flowing in thermal contact with the vehicle engine; a motorised fan unit for producing a forced circulation of air in contact with the heat exchanger, the motorised fan unit including a motor having power input terminals; an electric supply source; and a closed control box, the heat exchanger having an outer wall and the control box being mounted on said outer wall, and the apparatus further comprising: a temperature sensor for controlling the operation of the motorised fan unit according to the temperature of said cooling fluid; and means mounting the temperature sensor inside the heat exchanger so as to be in thermal contact with said cooling fluid flowing therein, the control box including said means mounting the temperature sensor, in projecting relationship from the control box, said switching means within the control box, and the apparatus further comprising electrical conductor means connecting the switching means directly with said electric supply source and motor input terminals, whereby the switching means can control the motorised fan unit in response to data from the temperature sensor; the apparatus further comprising a ballast resistor, the control box further including means mounting the ballast resistor in the control box in thermal contact with the interior of the heat exchanger so that the ballast resistor is in thermal contact with said coolant fluid in the heat exchanger, the ballast resistor being electrically connected through said switching means so that it can be electrically in series with the motor of the motorized fan unit whereby said motor can run at a reduced speed; wherein the ballast resistor is in the form of a winding, the means mounting it in the control box being such that the ballast resistor extends around the temperature sensor while being spaced from it, with the ballast resistor disposed within the heat exchanger.