Variable Speed Fan Drive Assembly.

摘要

This report covers designing, building and testing of a variable speed fan drive. Speed control automatic from 0 to approximately 4900 rpm governed by engine coolant temperature. Unit includes a fail safe device which operates the fan at maximum speed in the event of a control failure. Unit also includes a deepwater fording switch to reduce fan speed when engine compartment is flooded. Direction of rotation is counter-clockwise viewed from output end. Tests performed on unit included a functional check on speed modulation, declutching, fail safe devices and deep water fording switch operation. All these tests were performed using a 1765 rpm electric motor. A high speed test of approximately 4800 rpm was also made to assure satisfactory operation at elevated speed. Results obtained from above tests indicate that fan drive will perform satisfactorily, but final evaluation is best obtained by operating under actual engine conditions.