Patent ID: 6933687
Filing Date: 2005-08-23
Classification: F01P,F04D,Y02B

Abstract:
1. A dual motor configuration for driving two fans for moving air to cool an engine, the dual motor configuration comprising: a primary brushless motor constructed and arranged to be electronically controlled to drive a first fan over a range of speeds, and a secondary brush motor constructed and arranged to be electronically controlled to drive a second fan over a range of speeds, the secondary brush motor including an electronic switching device associated therewith for receiving a variable frequency pulse width modulated signal for controlling speed of the secondary brush motor, whereby different combinations of speeds of the first and second motors can be selectively chosen to meet cooling requirements of an engine, wherein each of the primary brushless motor and the secondary brush motor is constructed and arranged to be controlled to operate over a speed range of 0 to 4000 rpm.