Method for controlling clutch of vehicle with automated manual transmission

Patent metadata

Field	Value
Publication number	US-10640100-B2
Application number	US-201715827534-A
Country	US
Kind code	B2
Filing date	Nov 30, 2017
Priority date	Sep 25, 2017
Publication date	May 5, 2020
Grant date	May 5, 2020

Abstract

The present disclosure relates to a technique for improving durability of a clutch and shifting stability. The present disclosure provides a method of controlling a clutch of an automated manual transmission (AMT) vehicle, which reduces a micro-slip control time in order to improve durability of the clutch by performing a full-lock control of the clutch after slip control for learning a clutch characteristic curve. Additionally, the method shortens time to open the clutch for a subsequent shifting by predicting the time when a shift restarts after the full-lock control and by resuming the micro-slip control.

First claim

What is claimed is:

1. A method of controlling a clutch of an automated manual transmission (AMT) vehicle, the method comprising:
when a shift to current stage completes during an operation of the AMT vehicle, performing, with a controller, a micro-slip control of a clutch to learn clutch transmission torque characteristics, wherein the micro-slip control is a slip control performed in a state where an amount of slip of the clutch is maintained to a predetermined level;
when a slip releasing condition is satisfied based on the clutch transmission torque characteristics, performing, with the controller, a full-lock control of the clutch; and
when it is determined that a shift from the current stage to a target stage is required based on driving conditions including driving state of the AMT vehicle, performing, with the controller, the micro-slip control of the clutch until a shift to the target stage starts,
wherein performing the full-lock control of the clutch further comprises:
determining that the slip releasing condition is satisfied when an absolute value of a difference between an engine torque and a clutch torque is maintained below a first reference value for a first predetermined amount of time, and when an absolute value of the amount of slip of the clutch is maintained below a second reference value for a second predetermined amount of time.

2. The method of claim 1 , wherein performing the full-lock control of the clutch comprises:
controlling, with a clutch actuator, the clutch torque such that the clutch torque rises to maximum transmission torque on a clutch characteristic curve; and
turning off the clutch actuator when the clutch torque reaches the maximum transmission torque.

3. The method of claim 2 , wherein performing the micro-slip control of the clutch until the shift to the target stage starts further comprises:
turning on the clutch actuator to perform the micro-slip control of the clutch after the clutch actuator is turned off when the clutch torque reaches the maximum transmission torque.

4. The method of claim 1 , wherein performing the micro-slip control of the clutch until the shift to the target stage starts further comprises:
determining that a shift from the current stage to the target stage is required when an offset vehicle speed value is greater than or equal to a speed difference value, wherein the offset vehicle speed value is predicted based on an increase or a decrease of a current vehicle speed, and the speed difference value is calculated based on a difference between the current vehicle speed and a shifted vehicle speed.

5. The method of claim 1 , wherein performing the micro-slip control of the clutch until the shift to the target stage starts further comprises:
performing the micro-slip control of the clutch when an input shaft rotational speed is lower than a stall-prevention speed that is calculated by adding a predetermined speed value to a predetermined engine idling speed.

Assignees

• Hyundai Motor Co Ltd
• Kia Motors Corp

Inventors

• Cho Sung Hyun
• Cheong Seong Hwan

Classifications

• F16D48/06 Primary

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

• F16D2500/10412

  Transmission line of a vehicle · CPC title

• F16D2500/70494

  Vehicle speed · CPC title

• F16D2500/70276

  Slip · CPC title

• B60W10/06

  including control of combustion engines · CPC title