| 摘要 |
PROBLEM TO BE SOLVED: To make it able to be controlled to an optimum shift step in a stable manner by altering a shift characteristic in a direction where a yet higher speed step should be selected according to a drop in a slip resistance value. SOLUTION: Each signal out of various sensors in inputted into a control unit 50. As to these sensor, throttle sensor 7 emitting an output signal conformed to the extent of throttle opening and a car speed sensor 8 detecting a car speed upon detecting the revolution speed of an output shaft 5 of an automatic transmission 2 both are installed in this shift controller. To do shift control, first of all, a slip resistance value of a traveling road surface is detected, and a down-shift target value is set up according to the resistance value. Next, any acceleration resistance after the down-shift operation is predictively operated, whereby this acceleration resistance in the case of being down-shifted is compared with the down-shift target acceleration. If the acceleration resistance is more than the down-shit target acceleration, it is shifted down to such a shift step as being larger one step than the shift step where it becomes over- decelerated. |
