Microcontroller methods of improving reliability in DC brushless motors and cooling fans
AssigneeMinebea Co., Ltd.
InventorsScott Frankel, Eric Hardt, Nigel Strike
Life of this patent
Estimating the term…
Abstract
A method of controlling a motor speed for a fan assembly includes receiving a duty cycle value at a microcontroller. The microcontroller receives a measured fan speed from a speed sensor. An expected fan speed is determined, where the expected fan speed corresponds to the duty cycle value. The measured fan speed is compared with the expected fan speed. A duty cycle of a motor driving signal is reduced if the measured fan speed is less than a predetermined fraction of the expected fan speed.
Claims21
A method of controlling a motor speed for a fan assembly, comprising:
- receiving a duty cycle value at a microcontroller;
- receiving a measured fan speed, from a speed sensor;
- determining an expected fan speed based on the duty cycle value;
- comparing the measured fan speed with the expected fan speed;
- and
- reducing a duty cycle of a motor driving signal if the measured fan speed is less than a predetermined fraction of the expected fan speed.
A method of operating a cooling fan, comprising:
- monitoring a temperature of the cooling fan;
- determining if the temperature is within a predefined temperature window;
- multiplying a weighting factor, based on the temperature of the cooling fan, by a first number of revolutions to create a weighted number of revolutions;
- and
- adding the weighted number of revolutions to a total number of revolutions to create a total weighted number of revolutions.
A method of monitoring a cooling fan assembly, comprising:
- monitoring a plurality of points of interest of the cooling fan assembly;
- periodically capturing readings for each of the plurality of points of interest to create a number of measurements for each of the plurality of points of interest of the cooling fan assembly;
- storing the number of measurements for each of the plurality of points of interest in a memory;
- and
- transmitting the stored number of measurements for each of the plurality of the points of interest to an external receiver.
A method of monitoring a cooling fan, comprising:
- monitoring a plurality of measurement points in a cooling fan to capture readings for the plurality of measurement points;
- determining whether the readings for the plurality of measurement points are above a plurality of corresponding established thresholds for the plurality of measurement points;
- and
- modifying operation of the cooling fan if one or more of the plurality of readings is above the corresponding established threshold.
A method of operating a cooling fan, comprising:
- monitoring a temperature of the cooling fan;
- determining if the temperature is within a predefined temperature window;
- multiplying a weighting factor, based on the temperature of the cooling fan, by a first number of revolutions to create a weighted number of revolutions;
- adding the weighted number of revolutions to a total number of revolutions to create a total weighted number of revolutions;
- determining if the total weighted number of fan revolutions is greater than a milestone revolution target;
- and
- generating a message if the total weighted number of fan revolutions is greater than the milestone revolution target.
Dependencies are inferred from the claim text.