Twin fan control system and method
First Claim
1. A control system for controlling the speed of a plurality of fans for cooling a plurality of fluids in a work machine, each of said plurality of fluids being operative between a predetermined minimum threshold temperature and a predetermined maximum threshold temperature, said control system comprising:
- a plurality of sensors positioned to sense the temperature of each of the plurality of fluids, each sensor being operable to output a signal indicative of the temperature of that particular fluid;
an electronic controller coupled with said plurality of sensors for receiving signals therefrom, said controller being operable to receive a signal from each of said plurality of sensors indicative of a temperature for each of the plurality of fluids;
said controller being further operable to determine a desired fan speed for each of said plurality of fans based upon signals received from said plurality of sensors; and
said controller outputting a signal to each of said plurality of fans to individually control the speed thereof, each output signal being indicative of a desired fan speed for a particular fan and each output signal being based upon a comparison of at least some of the signals received from said plurality of sensors.
1 Assignment
0 Petitions
Accused Products
Abstract
A control system and method for controlling the speed of a plurality of fans for cooling a plurality of fluids in a work machine in accordance with the heat dissipation requirements of the particular heat transfer cores, the present control system including a plurality of sensors positioned to sense the temperature of each of the plurality of fluids, each sensor being operable to output a signal indicative of the temperature of that particular fluid. An electronic controller coupled to the sensors receives signals indicative of the temperature of each of the plurality of fluids, determines therefrom a desired fan speed for each fan, and outputs a signal to individually control the speed of each fan. Each output signal is based upon a comparison of at least some of the temperature error signals determined from the plurality of sensor signals.
105 Citations
35 Claims
-
1. A control system for controlling the speed of a plurality of fans for cooling a plurality of fluids in a work machine, each of said plurality of fluids being operative between a predetermined minimum threshold temperature and a predetermined maximum threshold temperature, said control system comprising:
-
a plurality of sensors positioned to sense the temperature of each of the plurality of fluids, each sensor being operable to output a signal indicative of the temperature of that particular fluid;
an electronic controller coupled with said plurality of sensors for receiving signals therefrom, said controller being operable to receive a signal from each of said plurality of sensors indicative of a temperature for each of the plurality of fluids;
said controller being further operable to determine a desired fan speed for each of said plurality of fans based upon signals received from said plurality of sensors; and
said controller outputting a signal to each of said plurality of fans to individually control the speed thereof, each output signal being indicative of a desired fan speed for a particular fan and each output signal being based upon a comparison of at least some of the signals received from said plurality of sensors. - View Dependent Claims (2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17)
said control system is further operable to determine a temperature error for each signal received from the sensors sensing the temperature of each of said first, second, third and fourth fluids, each of said temperature errors being computed based upon a difference between a predetermined desired threshold temperature for that particular fluid and the temperature of that particular fluid as indicated by the signal received from that fluid'"'"'s sensor;
said controller being operable to determine a fan speed for said first fan based upon the largest temperature error existing between the sensor signals received from said first, second, and third fluids; and
said controller being operable to determine a fan speed for said second fan based upon the largest temperature error existing between the sensor signals received from said first, second and fourth fluids.
-
-
14. The control system as set forth in claim 13, wherein said controller is operable to determine a fan speed for said first fan to be substantially the same as the fan speed for said second fan if the larger of the temperature errors for the first and second fluids exceeds the temperature errors for both the third and fourth fluids.
-
15. The control system as set forth in claim 1, wherein said controller is coupled to the work machine for receiving a power request signal therefrom, said control system determining the fan speed for each of said plurality of fans to be a minimum predetermined speed when said power request signal is received.
-
16. The control system as set forth in claim 15, wherein the fan speed for each of said plurality of fans is maintained at a minimum predetermined speed until a predetermined maximum threshold temperature for one of said fluids is reached.
-
17. The control system as set forth in claim 1, wherein said controller is coupled to the work machine for receiving a braking signal therefrom, said controller determining the fan speed for each of said plurality of fans to be a maximum predetermined speed for as long as said braking signal is received.
-
18. A control system for controlling the speed of two fans for cooling four fluids in a work machine, each fluid being associated with a particular heat transfer core and each fluid being operable between a predetermined minimum threshold temperature and a predetermined maximum threshold temperature, the control system comprising:
-
a first sensor positioned to sense the temperature of the first fluid and to output a signal indicative thereof;
a second sensor positioned to sense a temperature of the second fluid and to output a signal indicative thereof;
a third sensor positioned to sense a temperature of the third fluid and to output a signal indicative thereof;
a fourth sensor positioned to sense a temperature of the fourth fluid and to output a signal indicative thereof;
an electronic controller coupled with said first, second, third and fourth sensors for receiving signals therefrom, said controller being operable to receive a signal from each of said sensors indicative of the temperature of said first, second, third and fourth fluids respectively;
said controller being further operable to determine a first temperature error for the signal received from said first sensor, a second temperature error for the signal received from said second sensor, a third temperature error for the signal received from said third sensor, and a fourth temperature error for the signal received from said fourth sensor, each of said temperature errors being computed based upon a difference between a predetermined desired threshold temperature for that particular fluid and the temperature of that particular fluid as indicated by the signal received from that fluid'"'"'s sensor;
said controller being further operable to determined a fan speed for said first and second fans based upon a comparison of at least some of the temperature errors determined from said first, second, third and fourth sensors; and
said controller being further coupled to the drive motor of said first fan and to the drive motor of said second fan and outputting a signal respectively thereto to control the speed of said first and second fans, each output signal being indicative of a desired fan speed for that particular fan. - View Dependent Claims (19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32)
said controller being operable to determine a fan speed for said second fan based upon the largest temperature error existing between the signals received from said first, second and fourth sensors.
-
-
21. The control system as set forth in claim 20, wherein said controller is operable to determine a fan speed for said first fan to be substantially the same as the fan speed for said second fan if the larger of said first and second temperature errors exceeds both the third and fourth temperature errors.
-
22. The control system as set forth in claim 19, wherein said controller determines a fan speed for said first fan to be zero if the temperature of said third fluid is at a predetermined overcooled threshold temperature for that particular fluid.
-
23. The control system as set forth in claim 19, wherein said controller determines a fan speed for said second fan to be zero if the temperature of said fourth fluid is at a predetermined overcooled threshold temperature for that particular fluid.
-
24. The control system as set forth in claim 18, wherein said controller is coupled to the work machine for receiving a power request signal therefrom, said control system determining the fan speed for said first and second fans to be a minimum predetermined speed for each of said fans when said power request signal is received.
-
25. The control system as set forth in claim 24, wherein the fan speed for said first and second fans is maintained at a minimum predetermined speed until a predetermined maximum threshold temperature for one of said fluids is reached.
-
26. The control system as set forth in claim 18, wherein said controller is coupled to the work machine for receiving a braking signal therefrom, said controller determining the fan speed for said first and second fans to be a maximum predetermined speed for each such fan for as long as said braking signal is received.
-
27. The control system as set forth in claim 18, wherein said controller is further operable to scale each of said first, second, third and fourth temperature errors by a corresponding first, second, third and fourth predetermined value.
-
28. The control system as set forth in claim 19, wherein said first heat transfer core is an ATAAC core and wherein said first fluid is the inlet manifold air to said ATAAC core.
-
29. The control system as set forth in claim 28, wherein the predetermined desired threshold temperature for said first fluid is a function of the ambient air temperature, said control system further including a fifth sensor positioned to sense the ambient air temperature and to output a signal indicative thereof, said controller being coupled to said fifth sensor for receiving signals therefrom indicative of the ambient air temperature and said controller being further operable to at least periodically update the predetermined desired threshold temperature for said first fluid based upon the signals received from said fifth sensor.
-
30. The control system as set forth in claim 19, wherein said second heat transfer core is an engine coolant core and wherein said second fluid is the engine coolant.
-
31. The control system as set forth in claim 19, wherein said third heat transfer core is a hydraulic oil core and wherein said third fluid is the hydraulic oil.
-
32. The control system as set forth in claim 19, wherein said fourth heat transfer core is a transmission oil core and wherein said fourth fluid is the transmission oil.
-
33. A method for controlling the speed of a plurality of fans for cooling a plurality of fluids in a work machine, each of said plurality of fluids being operative between a predetermined minimum threshold temperature and a predetermined maximum threshold temperature, said method comprising the steps of:
-
positioning a plurality of sensors to sense the temperature of each of the plurality of fluids, each sensor being operable to output a signal indicative of the temperature of that particular fluid;
coupling an electronic controller with said plurality of sensors for receiving signals therefrom, said controller being operable to receive a signal from each of said plurality of sensors indicative of a temperature for each of the plurality of fluids;
operably determining a desired fan speed for each of said plurality of fans based upon signals received from said plurality of sensors utilizing said controller; and
outputting a signal to each of said plurality of fans to individually control the speed thereof utilizing said controller, each output signal being indicative of a desired fan speed for a particular fan and each output signal being based upon a comparison of at least some of the signals received from said plurality of sensors. - View Dependent Claims (34, 35)
-
Specification