Patent ID: 7508146
Filing Date: 2009-03-24
Classification: F01P,F04D,Y02B

Abstract:
1. A dual fan module system comprising: a first electric motor operating a first fan, a second electric motor operating a second fan, and switching structure constructed and arranged to operate the system at more than two different speeds, wherein the first motor is a two-speed motor having first and second commutators and associated first and second windings, and wherein the second motor is a one-speed motor, and wherein the switching structure includes at least a first switching device, a second switching device, a third switching device, and a fourth switching device, the first switching device is disposed between a positive lead of a power source and an input to the positive side first winding, the second switching device is disposed between the positive lead of the power source and an input to the positive side second winding, the third switching device is disposed between the positive lead of the power source after the second switching device and the positive power input to the one-speed motor after the fourth switching device, the fourth switching device is selectively associated with first and second contacts, such that when the fourth switching device engages the first contact, an output of the negative side of the second winding is connected with a negative lead of the power source, and when the fourth switching device engages the second contact, an output of the negative side of the second winding is connected to an input to the one-speed motor, and wherein an output of the one-speed motor is connected with the negative lead of the power source.