| 摘要 |
PROBLEM TO BE SOLVED: To provide a hydraulic control device for an automatic transmission which can reduce fuel consumption by appropriately controlling rotation speed of a mechanical pump at high speed rotation of an engine. SOLUTION: A hydraulic control device 10 for an automatic transmission is equipped with a mechanical pump 22 for supplying oil pressure to an automatic transmission by being driven by an engine 20 and an electric pump 30 for performing auxiliary supply of oil pressure to the automatic transmission at engine stop by being driven by a motor 32. A speed changer 24 is arranged midway between the engine 20 and a transmission system to the mechanical pump 22. The electric pump 30 is equipped with a switching valve 36 for switching the oil pressure from the electric pump 30 to the speed changer 24 during traveling. The transmission ratio of the speed changer 24 is variable by the oil pressure supplied from the electric pump 30. COPYRIGHT: (C)2011,JPO&INPIT |
