US 12,325,290 B2
Air filter monitoring system and method for a work machine
Kyle A. Holl, Durango, IA (US); and Scott J. Breiner, Dubuque, IA (US)
Assigned to DEERE & COMPANY, Moline, IL (US)
Filed by Deere & Company, Moline, IL (US)
Filed on Dec. 13, 2021, as Appl. No. 17/643,886.
Prior Publication US 2023/0182545 A1, Jun. 15, 2023
Int. Cl. B60H 3/06 (2006.01); B60H 1/00 (2006.01)
CPC B60H 3/0608 (2013.01) [B60H 1/00378 (2013.01); B60H 1/00828 (2013.01); B60H 1/00985 (2013.01); B60H 2003/0683 (2013.01)] 20 Claims
OG exemplary drawing
 
1. An air filter monitoring system for a work machine, the air filter monitoring system comprising:
a plenum having a fresh air intake through which a fresh air is drawn into the plenum, a recirculation air intake through which cab air is drawn from the cab into the plenum, and an outlet through which air is exhausted into the cab;
a pressurization blower between the fresh air intake and the outlet for causing airflow from the fresh air intake to the outlet;
a first motor for driving the pressurization blower as a function of the first motor control signal, the first motor control signal at a first motor speed;
a first motor current sensor for measuring a first current to maintain the first motor speed, the first motor current sensor providing a first motor current sensor signal indicative of the first current;
a recirculation blower between the recirculation air intake and the outlet for causing airflow from the recirculation air intake to the outlet;
a second motor for driving the recirculation blower as a function of a second motor control signal, the second motor control signal at a second motor speed;
a second motor current sensor for measuring a second current to maintain the second motor speed, the second motor current sensor providing a second motor current sensor signal indicative of the second current;
a speed selector for providing a speed select signal;
a fresh air filter for filtering air flowing from the fresh air intake to the pressurization blower;
a recirculation air filter for filtering cabin air flowing from the recirculation air intake to the outlet;
a pressurization blower speed sensor for providing a first speed sensor signal indicative of a speed of the pressurization blower, wherein the speed of the pressurization blower varies as a function of an airflow from the pressurization blower;
a recirculation blower speed sensor for providing a second speed signal indicative of the speed of the recirculation blower, wherein the speed of the recirculation blower varies as a function of the speed select signal; and
a non-transitory computer readable medium comprising a program instruction for permitting a controller to monitor the HVAC system, the program instruction when executed comprising causing a processor of the controller to:
produce a first and a second motor control signals to drive independently the pressurization blower and the recirculation blower, respectively, the first motor control signal being a function of the first speed sensor signal to maintain a constant speed from the pressurization blower to the outlet despite changes in the condition of the fresh air filter and the second motor control signal being a function of the speed select signal to maintain a constant speed from the recirculation blower to the outlet despite changes in the condition of the recirculation air filter monitor;
monitor the first motor current sensor signal and the second motor current sensor signal;
compare the first motor current sensor signal to a first baseline motor current sensor signal and the second motor current sensor signal to a second baseline motor current sensor signal; and
trigger a filter replacement action identifying the filter requiring replacement when the first motor current sensor signal falls below a first threshold value of the first baseline motor current sensor signal or the second motor current sensor signal falls below a second threshold value of the second baseline motor current sensor signal.