Jason B Carmichael

US Patent:

20190301972, Oct 3, 2019

Filed:

Apr 2, 2018

Appl. No.:

15/943233

Inventors:

- Plano TX, US
John A. Frazier - Fraziers Bottom WV, US
Jason D. Carmichael - Ravenswood WV, US

Assignee:

TOYOTA MOTOR ENGINEERING & MANUFACTURING NORTH AMERICA , INC. - Plano TX

International Classification:

G01M 13/02

Abstract:

A method and system of evaluating shift performance of an automatic transmission system having gears and a torque converter. The method includes driving the automatic transmission with an input motor while applying a rotational load by a pair of output motors. A command is applied to a solenoid to change fluid pressure, the time of issuance of the command is recorded, and the transmission shifts between a pair of the gears. Periodic measurements are made for transmission output torque. Threshold values are determined for the torque converter rotation speed and for the transmission output torque. A lag time is determined between the threshold for the turbine speed and the detected time for the solenoid. An engage time is determined based on the torque threshold and the turbine speed threshold. Lag time, peak transmission, and output torque are used to judge performance of the automatic transmission system.