Chrysler Corporation

Hans A Dourra

Howard L Benford

Maurice B Leising

Nabil M Issa

Samer H Halawi

Gary J Binienda

Spyros E Drutis

An interactive cruise control system and method for providing automatic speed control of a vehicle with improved shifting of an automatic transmission. The system and method controls speed of a vehicle equipped with cruise control and minimizes downshifts in an automatic transmission of the vehicle. Vehicle speed is detected and compared with a setpoint speed which is associated with the cruise control system. Transmission gear shifting is determined based on predetermined shift schedule points. Determined transmission gear downshifts are prevented for a kickdown delay period based on vehicle speed loss and the presence of vehicle deceleration. Also provided is an overspeed reduction method for causing a transmission downshift during an overspeed condition with the throttle closed. Further, the system provides hunting prevention between both second gear and third gear as well as between third gear and fourth gear for a four speed automatic transmission.

Kickdown delay in cruise control for automatic transmission

A method of determining the remaining useful life of automatic transmission fluid used in an automatic transmission or transaxle is provided. A multiplicity of vehicles having the same type of automatic transmission or transaxle are monitored and data on factors bearing on the useful life of automatic transmission fluid are collected. Weighted constants are derived for each factor. The automatic transmission controller is then programmed to monitor the operation of the automatic transmission or transaxle and collect data on the factors that bear on the useful life of the automatic transmission fluid. Based on the collected data and weighted constants, the remaining useful life of the automatic transmission fluid is determined.

Method to determine the remaining useful life of automatic transmission

An interactive cruise control system and method for providing automatic speed control of a vehicle with improved shifting of an automatic transmission. The system and method controls speed of a vehicle equipped with cruise control and minimizes downshifts in an automatic transmission of the vehicle. Vehicle speed is detected and compared with a setpoint speed which is associated with the cruise control system. Transmission gear shifting is determined based on predetermined shift schedule points. Determined transmission gear downshifts are prevented for a kickdown delay period based on vehicle speed loss and the presence of vehicle deceleration. Also provided is an overspeed reduction method for causing a transmission downshift during an overspeed condition with the throttle closed. Further, the system provides hunting prevention between both second gear and third gear as well as between third gear and fourth gear of a four speed automatic transmission.

Cruise control overspeed reduction with automatic transmission

Shift hunting prevention for an automatic transmission

A method of determining the deterioration of automatic transmission fluid by detecting shudder during the EMCC portion of air conditioner clutch engagement. Shudder is detected by calculating the acceleration of the turbine during EMCC slip with the following equation:

Growing community of inventors

Dearborn Heights, MI, United States of America

Hans A Dourra