Method for controlling clutch of vehicle with automated manual transmission

• US 10,640,100 B2
• Filed: 11/30/2017
• Issued: 05/05/2020
• Est. Priority Date: 09/25/2017
• Status: Active Grant

• Current Assignee: Hyundai Motor Company (Hyundai Motor Group), Kia Motors Corporation (Kia Corp.)
• Original Assignee: Hyundai Motor Company (Hyundai Motor Group)
• Inventors: Cho, Sung Hyun, Cheong, Seong Hwan
• Primary Examiner(s): Young, Edwin A
• Application Number:
  US15/827,534
• Publication Number:
  US 20190092311A1
• Time in Patent Office: 887 Days
• CPC Class Codes: B60W 10/02 including control of driveline clutches
• CPC Class Codes: B60W 10/06 including control of combustion engines
• CPC Class Codes: B60W 10/11 Stepped gearings
• CPC Class Codes: B60W 2050/0088 Adaptive recalibration
• CPC Class Codes: B60W 2510/0208 Clutch engagement state, e.g. engaged or disengaged
• CPC Class Codes: B60W 2510/0241 Clutch slip, i.e. difference between input and output speeds
• CPC Class Codes: B60W 2510/0275 Clutch torque
• CPC Class Codes: B60W 2510/0657 Engine torque
• CPC Class Codes: B60W 30/19 Improvement of gear change, e.g. by synchronisation or smoothing gear shift
• CPC Class Codes: F16D 2500/10412 Transmission line of a vehicle
• CPC Class Codes: F16D 2500/1045 Friction clutch
• CPC Class Codes: F16D 2500/1083 Automated manual transmission
• CPC Class Codes: F16D 2500/1107 Vehicles
• CPC Class Codes: F16D 2500/30412 Torque of the input shaft
• CPC Class Codes: F16D 2500/3065 Torque of the engine
• CPC Class Codes: F16D 2500/50236 Adaptations of the clutch characteristics, e.g. curve clutch capacity torque - clutch actuator displacement
• CPC Class Codes: F16D 2500/50239 Soft clutch engagement
• CPC Class Codes: F16D 2500/5048 Stall prevention
• CPC Class Codes: F16D 2500/5126 Improving response to driver inputs
• CPC Class Codes: F16D 2500/70276 Slip
• CPC Class Codes: F16D 2500/70494 : Vehicle speed
• CPC Class Codes: F16D 2500/70605 : Adaptive correction; Modifying control system parameters, e.g. gains, constants, look-up tables
• CPC Class Codes: F16D 2500/70657 : Predictor methods
• CPC Class Codes: F16D 48/06 : Control by electric or electronic means, e.g. of fluid pressure

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.

Claims

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.