Brushless DC ring motor cooling system

• US 20030173916A1
• Filed: 05/16/2003
• Published: 09/18/2003
• Est. Priority Date: 05/03/2000
• Status: Active Grant

• Current Assignee: Horton Incorporated
• Original Assignee: Horton Incorporated
• Inventors: Nelson, Christopher A., Palmer, Bradford K.
• Granted Patent: US 6,912,353 B2
• Time in Patent Office: Days
• US Class Current: 318/268
• CPC Class Codes: F01P 11/10 Guiding or ducting cooling-air, to, or from, liquid-to-air heat exchangers
• CPC Class Codes: F01P 2005/046 with electrical pump drive
• CPC Class Codes: F01P 7/048 using electrical drives
• CPC Class Codes: F04D 25/0633 Details of the magnetic circuit
• CPC Class Codes: F04D 25/064 Details of the rotor
• CPC Class Codes: F04D 25/0646 Details of the stator
• CPC Class Codes: F04D 25/08 the working fluid being air, e.g. for ventilation
• CPC Class Codes: F04D 29/582 specially adapted for elastic fluid pumps
• CPC Class Codes: H02K 1/187 to inner stators
• CPC Class Codes: H02K 5/1735 radially supporting the rotary shaft at only one end of the rotor H02K5/1737 takes precedence
• CPC Class Codes: H02K 7/14 Structural association with mechanical loads, e.g. with hand-held machine tools or fans with fan or impeller for cooling the machine H02K9/06

Abstract

A cooling system for a vehicle includes a shroud attachable to a fixed portion of the vehicle. A stator assembly for a brushless DC ring motor is attached to at least one mounting support of the shroud. A cooling fan is piloted on the stator assembly, and includes a ring supporting a plurality of fan blades for sweeping an area inside the shroud. A rotor assembly for the brushless DC ring motor is attached to the ring of the cooling fan. The rotor assembly confronts the stator assembly around an outer diameter of the stator assembly. The cooling system is controlled by an electronic controller to rotate the cooling fan to provide appropriate cooling for the vehicle.

Claims

1. A method of operating a cooling fan in a cooling system for a vehicle, the method comprising:

determining a required speed of the cooling fan; and

providing first and second signals to a motor controller operatively connected to a motor having a rotatable portion connected to the cooling fan, the first signal coarsely controlling a rotational speed of the motor and the second signal finely controlling the rotational speed of the motor so that the cooling fan rotates at the required speed.

2. The method of claim 1, wherein the step of determining the required speed of the cooling fan comprises:

analyzing a pulse width modulated (PWM) signal from the engine control module (ECM) of the vehicle.

3. The method of claim 1, wherein the step of determining the required speed of the cooling fan comprises:

analyzing digital signals from a serial line of the engine control module (ECM) of the vehicle.

4. The method of claim 1, further comprising:

converting low DC voltage, high current power provided by a power source into a high voltage, low current signal for operating the motor.

5. The method of claim 4, wherein the power source is a vehicle battery.

6. The method of claim 5, further comprising:

selectively drawing stored power from the vehicle battery to operate the motor in demanding cooling conditions.

7. A method of operating a cooling fan in a cooling system for a vehicle, the method comprising:

analyzing digital signals from a serial line of the engine control module (ECM) of the vehicle to determine a required speed of the cooling fan; and

providing at least one signal to a motor controller operatively connected to a motor having a rotatable portion connected to the cooling fan, the at least one signal being related to a rotational speed of the cooling fan in such a manner that the cooling fan rotates at the required speed.

8. The method of claim 7, wherein the step of providing at least one signal to the motor comprises:

providing first and second signals to the motor controller, the first signal coarsely controlling the rotational speed of the motor and the second signal finely controlling the rotational speed of the motor so that the cooling fan rotates at the required speed.

9. The method of claim 7, further comprising:

converting low DC voltage, high current power provided by a power source into a high voltage, low current signal for operating the motor.

10. The method of claim 9, wherein the power source is a vehicle battery.

11. The method of claim 10, further comprising:

selectively drawing stored power from the vehicle battery to operate the motor in demanding cooling conditions.

12. A method of operating a cooling fan in a cooling system for a vehicle, the method comprising:

determining a required speed of the cooling fan;

converting low DC voltage, high current power provided by a battery of the vehicle into a high voltage, low current signal for operating a motor that drives the cooling fan, the high voltage, low current signal being controlled to provide gross adjustment of a speed of the motor; and

providing the high voltage, low current signal to the motor with a control adjustment to provide fine adjustment of the speed of the motor.

13. The method of claim 12, wherein the step of determining a required speed of the cooling fan is performed by a control/communications system operatively connected to an engine control module (ECM) of the vehicle.

14. The method of claim 13, wherein the step of determining a required speed of the cooling fan comprises:

analyzing a pulse width modulated (PWM) signal from the ECM of the vehicle.

15. The method of claim 13, wherein the step of determining the required speed of the cooling fan comprises:

analyzing digital signals from a serial line of the ECM of the vehicle.

16. The method of claim 13, wherein the step of converting low DC voltage, high current power provided by the battery of the vehicle into the high voltage, low current signal for operating the motor is performed by a DC-to-DC converter connected to the vehicle battery under the control of signals relayed by a commutation switching segment from the control/communications system.

17. The method of claim 16, wherein the step of providing the high voltage, low current signal to the motor with a control adjustment to provide fine adjustment of the speed of the motor is performed by the commutation switching segment.

18. The method of claim 12, wherein the high voltage, low current signal is adjustable over a 2-to-1 range during the step of converting low DC voltage, high current power provided by the battery of the vehicle into the high voltage, low current signal for operating the motor.

19. The method of claim 12, wherein the motor is a three phase motor and the step of providing the high voltage, low current signal to the motor with a control adjustment to provide fine adjustment of the speed of the motor comprises:

arranging at least one switch to control a voltage and current provided to each of the phases of the motor.