Damper clutch control method for automatic transmission

• US 6,478,717 B1
• Filed: 10/27/2000
• Issued: 11/12/2002
• Est. Priority Date: 10/29/1999
• Status: Expired due to Fees

• Current Assignee: Hyundai Motor Company (Hyundai Motor Group)
• Original Assignee: Hyundai Motor Company (Hyundai Motor Group)
• Inventors: Yu, Pyung-Hwan
• Primary Examiner(s): Estremsky, Sherry
• Assistant Examiner(s): Lewis, Tisha D.
• Application Number:
  US09/697,321
• Time in Patent Office: 746 Days
• Field of Search: 477/175, 477/176, 477/64, 477/169, 477/180, 192/3.28, 192/3.31
• US Class Current: 477/175
• CPC Class Codes: F16H 2059/385 Turbine speed
• CPC Class Codes: F16H 2059/467 of torque converter
• CPC Class Codes: F16H 59/141 of rate of change of torque or torque demand
• CPC Class Codes: F16H 59/36 Inputs being a function of speed
• CPC Class Codes: F16H 61/143 using electric control means

Abstract

A damper clutch control method comprising the steps of detecting a throttle opening, an engine rpm and an turbine rpm; performing lift-foot-up shifting if throttle opening is abruptly decreased; determining if a difference in engine rpm and turbine rpm is below a predetermined value; and duty controlling a damper clutch if the difference in engine rpm and turbine rpm is below the predetermined value.

Claims

1. A damper clutch control method comprising the steps of:

detecting a throttle opening, an engine rpm and a turbine rpm;

performing lift-foot-up shifting if throttle opening is abruptly decreased;

determining if a difference in engine rpm and turbine rpm is below a predetermined value; and

controlling a duty of a damper clutch if the difference in engine rpm and turbine rpm is below the predetermined value such that the engine rpm is maintained to be larger than or equal to the turbine rpm.

2. The damper clutch control method of claim 1 wherein the predetermined value of the difference in engine rpm and turbine rpm is approximately 100 rpm.

3. The damper clutch control method of claim 1 wherein the step of controlling the duty of the damper clutch is performed for a predetermined duration and at a predetermined duty and then at an engaging duty, after which the duty is controlled such that engine rpm and turbine rpm are equal.