Shift Characteristics of a 4-Speed Automatic Transmission

1999-01-1060

03/01/1999

Event
International Congress & Exposition
Authors Abstract
Content
The 1-2 shift characteristics of a 4-speed automatic transmission are examined. Shift quality fundamentals and ratio change mechanics are discussed, and shift quality metrics are introduced. A simple model is developed to describe the shift characteristics. Powertrain dynamometer data illustrate the effects of throttle position, band-brake capacity, spark timing, and transmission fluid temperature. Band-brake apply pressure largely determines the inertia phase output shaft torque. Retarded spark timing permits substantial reduction of vibration dose value at constant shift duration. Due to increased viscous torque from the drum interface oil film, band capacity significantly increases during the first 0.1-0.2 s of the inertia phase for temperatures less than 40 C.
Meta TagsDetails
DOI
https://doi.org/10.4271/1999-01-1060
Pages
15
Citation
Megli, T., Haghgooie, M., and Colvin, D., "Shift Characteristics of a 4-Speed Automatic Transmission," SAE Technical Paper 1999-01-1060, 1999, https://doi.org/10.4271/1999-01-1060.
Additional Details
Publisher
Published
Mar 1, 1999
Product Code
1999-01-1060
Content Type
Technical Paper
Language
English