US 8,897,983 B2 · System and method for using vehicle parasitic loads to aid with vehicle speed retardation

Abstract

A system and method for providing additional speed retardation capacity is disclosed that utilizes parasitic loads of the vehicle. A vehicle is disclosed that includes a vehicle control system for sensing overspeed conditions, a powertrain, and a parasitic load. When an overspeed condition is detected, the parasitic load that is normally deactivated to improve efficiency is activated to remove power from the powertrain. Temperature sensors can monitor a load temperature and the parasitic loads can be controlled based on the temperature readings. A method is disclosed that includes detecting overspeed conditions, activating parasitic loads to absorb power when an overspeed condition is detected, and deactivating the loads when the overspeed condition ceases. The parasitic loads can be controlled separately or together. The method can include cumulative actions based on greater overspeed conditions.

Claims20

Dependent claims

A vehicle comprising:

a vehicle control unit for sensing a plurality of overspeed conditions;
a powertrain;
at least one of a transmission retarder, an engine brake and service brakes coupled to the vehicle control unit for slowing down the vehicle;
a parasitic load coupled to the vehicle control unit that draws power from the powertrain;
wherein when the vehicle control unit senses a first overspeed condition, the vehicle control unit takes over throttle control from a vehicle operator;
wherein when the vehicle control unit senses a second overspeed condition, the vehicle control unit activates at least one of the transmission retarder, the engine brake and the service brakes;
and
wherein when the vehicle control unit senses a third overspeed condition, the vehicle control unit activates the parasitic load;
the third overspeed condition being at a greater speed than the second overspeed condition.

6 more elements

A method for using vehicle parasitic loads to aid with speed retardation of a vehicle, the method comprising:

monitoring a vehicle to detect overspeed conditions;
taking over of throttle control from a vehicle operator by a vehicle control unit when the vehicle speed exceeds a first overspeed threshold;
restoring throttle control to the vehicle operator by the vehicle control unit when the vehicle speed drops below the first overspeed threshold;
activating at least one of transmission retardation, engine brake and service brakes by the vehicle control unit when the vehicle speed exceeds a second overspeed threshold, the second overspeed threshold being greater than the first overspeed threshold;
deactivating any activated ones of the transmission retardation, engine brake and service brakes by the vehicle control unit when the vehicle speed drops below the second overspeed threshold;
activating a parasitic load by the vehicle control unit to absorb power from the powertrain when the vehicle speed exceeds a third overspeed threshold, the third overspeed threshold being greater than the second overspeed threshold;
and
deactivating the parasitic load when the vehicle speed drops below the third overspeed threshold.

5 more elements

Dependencies are inferred from the claim text.

System and method for using vehicle parasitic loads to aid with vehicle speed retardation

Life of this patent

System and method for using vehicle parasitic loads to aid with vehicle speed retardation

Life of this patent

Abstract

Claims20