Vehicle with engine power limiting based on clutch capacity

Patent metadata

Field	Value
Publication number	US-11718174-B2
Application number	US-202117329415-A
Country	US
Kind code	B2
Filing date	May 25, 2021
Priority date	May 25, 2021
Publication date	Aug 8, 2023
Grant date	Aug 8, 2023

Abstract

An all-wheel-drive vehicle includes a primary axle operably coupled to an engine and a secondary axle having an input operably coupled to the engine a first halfshaft, a second halfshaft, a first clutch selectively connecting the first halfshaft to the input, and a second clutch selectively connecting the second halfshaft to the input. A transmission has an input coupled to the engine and output coupled to the primary drive axle. A driveshaft couples a power-transfer unit and the input, and a third clutch selectively couples the output to the driveshaft. A controller is programmed to, during a power-limiting routine, command a torque to the engine based on closed-loop feedback control such that the torque decreases when a calculated slip of a selected one of the first and second clutches is greater than a target slip of the selected clutch and increases when the calculated slip is less than the target slip.

First claim

What is claimed is:

1. An all-wheel-drive vehicle comprising:
an engine;
a primary axle operably coupled to the engine;
a secondary axle including an input operably coupled to the engine, a first halfshaft, a second halfshaft, a first clutch selectively connecting the first halfshaft to the input, and a second clutch selectively connecting the second halfshaft to the input; and
a transmission having an input coupled to the engine and output coupled to the primary drive axle;
a power-transfer unit coupled to the transmission and including a third clutch; and
a driveshaft coupling the power-transfer unit and the input, wherein the third clutch selectively couples the output to the driveshaft;
a controller programmed to, during a power-limiting routine, command a torque to the engine based on closed-loop feedback control such that the torque decreases when a calculated slip of a selected one of the first and second clutches is greater than a target slip of the selected clutch and increases when the calculated slip is less than the target slip.

2. The all-wheel-drive vehicle of claim 1 , wherein the target slip is greater than zero.

3. The all-wheel-drive vehicle of claim 1 , wherein the target slip is based on vehicle speed and a temperature of the clutch.

4. The all-wheel-drive vehicle of claim 1 , wherein the controller is further programmed to initiate the power-limiting routine responsive to the calculated slip, a temperature of the clutch, and a power of the selected clutch satisfying initiation criterion.

5. The all-wheel-drive vehicle of claim 1 , wherein the target slip is based on a drive mode of the vehicle.

6. The all-wheel-drive vehicle of 1 , wherein the torque commanded to the engine is based on a summation of a proportional component torque, an integral component torque, and a differential component torque.

7. The all-wheel-drive vehicle of claim 6 , wherein the controller is further programmed to increase the torque commanded to the engine when the summation is less than a lower limit such that the torque commanded to the engine is greater than or equal to the lower limit.

Assignees

• Ford Global Tech Llc

Inventors

• Harris Nicholas
• Monticello Andrew
• Culek Kyle
• Rodrigues Ashok E

Classifications

• B60K23/08 Primary

  for changing number of driven wheels {, for switching from driving one axle to driving two or more axles (B60K17/3515 takes precedence)} · CPC title

• B60K17/02

  characterised by arrangement, location, or kind of clutch · CPC title

• B60K17/348

  having differential means for driving one set of wheels, e.g. the front, at one speed and the other set, e.g. the rear, at a different speed (B60K17/346 takes precedence) · CPC title

• F16D48/06

  Control by electric or electronic means, e.g. of fluid pressure · CPC title

• F16D2500/10431

  4WD Clutch dividing power between the front and the rear axle · CPC title