Electric motor having an improved airflow cooling system

DETAILED DESCRIPTION The present invention is directed to a switched reluctance motor that creates an improved airflow path for cooling motor components in an efficient manner.
The motor includes a support frame having an upper and lower frame, a stator having among other components four stator poles formed of multiple laminations, and a rotor having a shaft and four rotor poles formed of multiple laminations.
The rotor is mounted for rotation within the stator, which is secured to the support frames.
A centrifugal fan mounted to the motor shaft is also provided for circulating air through the motor to keep the motor cool during operation.
A rotary position encoder mounted to the shaft beneath the centrifugal fan is further provided for determining the speed, direction, and position of the motor rotor.
In one aspect of the present invention, the electrical functions are divided between an upper and a lower circuit board.
The upper circuit board is secured to the upper frame in one horizontal plane perpendicular to the rotor, and the lower circuit board is secured to the upper frame in another horizontal plane.
The centrifugal fan is mounted within an opening formed in the upper circuit board and is disposed above the lower circuit board.
This construction allows the airflow to pass across both the upper and lower circuit boards to thereby dissipate any heat that may be generated by these devices.
The airflow is also directed across sidewalls which are part of the support frame.
These sidewalls act as a heat sink for electronic power devices secured to the sidewalls and connected to the upper circuit board.
The airflow assists in removing heat generated by the electronic power devices.
The present invention also provides an additional pair of centrifugal fans that are disposed above and below the rotor laminations.
These devices direct the airflow across the rotor, stator and stator coils thereby cooling these devices and expelling the air out of ports formed in the support frame.
The centrifugal fan disposed above the rotor laminations expels the air from the flow path created by the centrifugal fan mounted within the opening in the upper circuit board