To finish a speed change in an early stage while preventing the generation of an abnormal sound in an entire car speed area.
A speed change control device sets a synchronization deviation changing in proportional to the bigness of the rotation speed of a target motor and when a real motor rotation speed of the motor 1 for running synchronization-controlled of the motor is entered in this synchronization deviation, the control for changing a transmission 3 to a target speed change ratio is adopted and the speed change of a low car speed area with a small rotation speed difference of in/out gears judges synchronously by the synchronization deviation difference D1 of a small value suitable for this rotation speed difference and the speed change of the middle car speed area with the middle level rotation speed difference of in/out gears judges synchronously by the synchronization deviation D2 of a middle level value suitable for this rotation speed difference and the speed change of a high car speed area with a big rotation speed difference of in/out gears judges synchronously by the synchronization deviation D3 of a big value suitable for this rotation speed difference and even in the speed change of either car speed area, the synchronization judgement is carried out by the value near to the rotation speed difference of in/out gears and then the speed change is finished in an early stage.
TAKEDA NOBUAKI
HORII YUSUKE
