| 摘要 |
PROBLEM TO BE SOLVED: To enable the correction of a characteristic map so as to make command pressure to coincide with required pressure for fastening of a frictional element even when operation characteristics are varied, during a torque phase at the time of down-shifting. SOLUTION: This transmission integrates gear ratio deviation during a torque phase (4) at the time of shifting down from fourth to third speed in power-ON running, which deviation is obtained when a gear ratio gr exceeds a reference gear ratio gr5 at little higher than a synchronous rotation gear ratio gr4 . When the integration value is higher than a set value, a fastening side characteristic map is so corrected that a command is given so as to higher a first shelf pressure P4 to be applied to a fastening side frictional element during the torque phase. When the integration value is lower than the set value, the fastening characteristic map is so corrected that a command is given so as to lower the first shelf pressure P4 . |
