| 摘要 |
PURPOSE: To realize selection of the optimum shift stage for each action condition by determining a hysteresis quantity depending on time between shift-up and shift-down of an automatic transmission for an electronic-controlled vehicle, and selecting a basic hysteresis quantity without depending on time to be small. CONSTITUTION: As a shifting process is conducted, a time counter (t) is set at zero, a demand Ms of a driver, a vehicle speed V, and a specified hysteresis Sd (shiftup process) or Su (shiftdown process) are read, and if a hysteresis component Sz to t=0 is positive or negative is determined. After downshifting, when Ms<Su+Sz is satisfied, upshifting is conducted, while in the case of Ms>Su+Sz, the time counter (t) is increased for a time stage dt, and a time- dependent component Sz is increased to a value 1 as time passes. As time passes, short-time hysteresis is eliminated, but a constant hysteresis characteristic quantity Sh only acts, thereby the optimum number of speed can be selected. |
