System and method using fan control to assist vehicle braking
AssigneeGM Global Technology Operations LLC
InventorsMaqsood Rizwan ALI KHAN, Mark R. CLAYWELL, Paul M. RIHERD, II, Bryston HOLLIS
Life of this patent
Estimating the term…
Abstract
A system for controlling a fan of a vehicle engine. The system comprises: i) a fan configured to selectively cool the vehicle engine; and ii) an engine control module configured to: a) turn on the fan when the engine temperature exceeds a selected temperature threshold; b) determine when the vehicle engine is operating in an engine braking mode; and c) in response to the engine operating in the engine braking mode, turn on the fan when the engine temperature is below the selected temperature threshold. The engine control module turns the fan off as a means of hardware protection of the fan clutch even during engine braking modes.
Claims14
A system for controlling a fan of a vehicle engine comprising:
- a fan configured to selectively cool the vehicle engine;
- and
- an engine control module configured to:
- turn on the fan when an engine temperature exceeds a selected temperature threshold;
- determine when the vehicle engine is operating in an engine braking mode;
- in response to the vehicle engine operating in the engine braking mode, turn on the fan when the engine temperature is below the selected temperature threshold;
- select a speed curve from a group of speed curves based on a temperature and an air pressure condition;
- select a speed threshold value from the selected speed curve;
- determine whether an engine speed is greater than the selected speed threshold value;
- in response to a determination that the engine speed is greater than the selected speed threshold value, turn off the fan;
- in response to a determination that the engine speed is not greater the selected speed threshold value, maintain engagement of the fan;
- and
- increase slip of a clutch of the fan as the selected speed threshold value increases.
6-8. (canceled)
A method for controlling a fan of a vehicle engine comprising:
- engaging a fan to selectively cool the vehicle engine when an engine temperature exceeds a selected temperature threshold;
- determining when the vehicle engine is operating in an engine braking mode;
- and
- in response to the vehicle engine operating in the engine braking mode, engaging the fan when the engine temperature is below the selected temperature threshold;
- selecting a speed curve from a group of speed curves based on a temperature and an air pressure condition;
- selecting a speed threshold value from the selected speed curve;
- determining whether an engine speed is greater than the selected speed threshold value;
- in response to a determination that the engine speed is greater than the selected speed threshold value, turning off the fan;
- in response to a determination that the engine speed is not greater the selected speed threshold value, maintaining engagement of the fan;
- and
- increasing slip of a clutch of the fan as the selected speed threshold value increases.
13-15. (canceled)
A system for controlling a fan of a vehicle engine comprising:
- a fan configured to selectively cool the vehicle engine;
- an electronically controlled mechanical clutch configured to selectively turn on the fan;
- and
- an engine control module configured to:
- cause the electronically controlled mechanical clutch to turn on the fan when an engine temperature exceeds a selected temperature threshold;
- determine when the vehicle engine is operating in an engine braking mode;
- in response to the vehicle engine operating in the engine braking mode, cause the electronically controlled mechanical clutch to turn on the fan when the engine temperature is below the selected temperature threshold;
- select a speed curve from a group of speed curves based on a temperature and an air pressure condition;
- select a speed threshold value from the selected speed curve;
- determine whether an engine speed is greater than the selected speed threshold value;
- in response to a determination that the engine speed is greater than the selected speed threshold value, turn off the fan;
- in response to a determination that the engine speed is not greater the selected speed threshold value, maintain engagement of the fan;
- and
- increase slip of the electronically controlled mechanical clutch as the selected speed threshold value increases.
18-20. (canceled)
Dependencies are inferred from the claim text.