Methods and systems for a two-speed accessory drive of an engine
AssigneeFord Global Technologies, LLC
InventorsTimothy Vaughn, David Ord, George Papaioannou, Joseph Lyle Thomas, John Brevick
Life of this patent
Estimating the term…
Abstract
Methods and systems are provided for engaging and disengaging an electromagnetic clutch of a two-speed accessory drive of an engine of a vehicle. In one example, a method comprises, responsive to an electrical demand being higher than a threshold electrical demand, operating an electric machine of the vehicle in a motor mode to reduce a speed of a grounding gear of a planetary gear set of a two-speed accessory drive (TSAD) of the vehicle; and engaging an electromagnetic clutch responsive to the speed of the grounding gear reaching a clutch engagement threshold speed.
Claims16
A method for a vehicle, comprising:
- responsive to an electrical demand being higher than a threshold electrical demand, operating an electric machine of the vehicle in a motor mode to reduce a first speed of a grounding gear of a planetary gear set of a two-speed accessory drive (TSAD) of the vehicle;
- and
- engaging an electromagnetic clutch responsive to the first speed of the grounding gear reaching a clutch engagement threshold speed.
A system for a vehicle, comprising:
- an engine including a crankshaft;
- a two-speed accessory drive (TSAD) rotationally coupled to the crankshaft, the TSAD comprising a planetary gear set including an output gear and an electromagnetic clutch;
- and
- a controller with computer readable instructions stored on non-transitory memory that when executed during operation of the vehicle, cause the controller to:
- responsive to an electrical demand being higher than a threshold electrical demand, increase a speed of the output gear of the planetary gear set;
- and
- responsive to the speed of the output gear achieving a target speed, engage the electromagnetic clutch,
- wherein the planetary gear set further includes an input gear and a grounding gear, and wherein the controller includes further instructions stored on the non-transitory memory that, when executed, cause the controller to:
- maintain a speed of the input gear of the planetary gear set constant and reduce a speed of the grounding gear while increasing the speed of the output gear.
A method for a two-speed accessory drive (TSAD) of a vehicle, comprising:
- in a first condition, increasing a speed of an output gear of a planetary gear set of the TSAD to reduce a speed of a grounding gear of the planetary gear set;
- in a second condition, decreasing the speed of the output gear of the planetary gear set to increase the speed of the grounding gear,
- wherein increasing the speed of the output gear of the planetary gear set comprises operating an electric machine to apply a first torque to a drive belt coupling the electric machine and the output gear, and wherein decreasing the speed of the output gear of the planetary gear set comprises operating the electric machine to apply a second torque to the drive belt coupling the electric machine and the output gear;
- and
- in the first condition, engaging an electromagnetic clutch to couple the grounding gear after reducing the speed of the grounding gear to a clutch engagement threshold speed;
- and
- in the second condition, disengaging the electromagnetic clutch before increasing the speed of the grounding gear to the engine speed.
Dependencies are inferred from the claim text.