AUTOMATIC TRANSMISSION FOR VEHICLE

摘要

Provided is an automatic transmission for a vehicle, wherein oil pressure from an electric oil pump (10e) maintains the engaged state of friction engagement elements of a sub speed-changing mechanism (30) whilst an engine (1) is stopped, the automatic transmission including: a torque converter (2) that is provided between the engine (1) and a drive wheel (7); the sub speed-changing mechanism (30) that is provided in series with the torque converter (2); a mechanical oil pump (10m) that is driven by the engine (1); a controller (12) that stops the engine (1) when coasting stop criteria are met, the criteria including a vehicle speed being equal to or below the vehicle speed (VSP2) at which a coasting stop is permitted; and the electric oil pump (10e) that is driven by a battery (13) whilst the engine (1) is stopped. The controller (12) is configured so as to determine, on the basis of the vehicle speed and the turbine rotational speed (Nt) of the torque converter (2), whether the engine (1) can be stopped.