Gear determination apparatus, gear determination method, gear-shift instruction apparatus and gear-shift instruction method

摘要

When the vehicle speed change rate is equal to or higher than a predetermined value due to hard deceleration or hard acceleration (step ST2, step ST3), determination of the currently-selected gear based on the ratio of the engine speed to the vehicle speed which corresponds to the gear ratio (NVR) is prohibited, and the gear that is determined immediately before the prohibition is continuously set as the currently-selected gear (step ST7). According to this determination terminating control, it is possible to avoid an erroneous determination on the currently-selected gear, even if the calculated NVR is lower or higher than the theoretical NVR because of a delay in calculation of the vehicle speed due to hard deceleration or hard acceleration. As a result, it is possible to avoid the problem that, for example, a downshifting instruction is erroneously issued when 1st gear has been selected or an upshifting instruction is erroneously issued when the highest gear has been selected.