Patent ID: 8365889

Claim:
An automatic transmission, comprising: a starting apparatus having a housing that rotates based on torque of a driving source, and a clutch mechanism portion positioned in the housing; an oil pump that is positioned on a side opposite to the driving source with respect to the starting apparatus in a rotational axis direction of the housing, and is driven by transmission of rotation of the housing; an oil pump housing in which the oil pump is accommodated; and a speed change mechanism that is positioned on a side opposite to the starting apparatus with respect to the oil pump housing in the rotational axis direction, and has an input shaft, which extends through the oil pump and the oil pump housing and is connected to the clutch mechanism portion, wherein the clutch mechanism portion operates so as to selectively allow and block torque transfer from the driving source to the input shaft, the housing includes a cylindrical pump drive shaft extending along the rotational axis toward the oil pump housing, where the pump drive shaft has an inner peripheral surface that faces an outer peripheral surface of the input shaft, the oil pump is positioned on an outer peripheral side of the pump drive shaft, the oil pump housing has a pump through hole, which is provided at a position between the oil pump and the speed change mechanism in the rotational axis direction, and through which the input shaft extends, a support member for rotatably supporting the input shaft at an end on the oil pump side of the pump through hole is positioned between an inner peripheral surface of the pump through hole and the outer peripheral surface of the input shaft, the clutch mechanism portion is structured to allow the torque transfer from the driving source to the input shaft when the oil is supplied into a supply space formed in the starting apparatus, the clutch mechanism portion has a connection member for connecting to the input shaft, and the supply space is provided at a position adjacent to the connection member, a first supply flow path extending along the rotational axis, a second supply flow path extending from the first supply flow path toward the connection member, and a third supply flow path extending from the first supply flow path toward a position located closer to the speed change mechanism than the support member in the pump through hole are formed in the input shaft, and a communication flow path for allowing the second supply flow path and the supply space to communicate with each other is formed in the connection member, and the clutch mechanism portion allows the torque transfer from the driving source to the input shaft when the oil is supplied into the supply space through the third supply flow path, the first supply flow path, the second supply flow path, and the communication flow path.