PURPOSE: To ensure an excellent shift feeling free from engine racing and an interlock shock regardless of a starting car speed during a down shift, in a car speed oil pressure control device for an automatic transmission having a shift mode wherein a down shift is conducted through monitoring of a gear ratio.
CONSTITUTION: A reference gear ratio setting means (f) is a means to effect setting based on the number of revolutions from a number of revolutions detecting means (i), which detects at least one of the number of revolutions of an input shaft, the number of revolutions of an output shaft, and the number of revolutions of an engine, in such a manner that the more a detecting number of revolutions detecting value is higher, the more a reference gear ratio is set to a higher value. Further, a reference gear ratio setting means (f) is a means to effect setting based on a rate of change of a gear ratio from a rate of change of gear ratio computing means (j), which computes a rate of change of a gear ratio under a shift, in such a manner that the more a computing rate of change of a gear ratio is higher, the more a reference gear ratio is set to a lower value.
HIROSE IKUO
FUJITA YOSHIFUMI
Next Patent: LOCKUP RELEASE CONTROL DEVICE FOR TORQUE CONVERTER