Patent ID: 11739800

Abstract:
A first multi-plate brake device and a second multi-plate brake device are arranged side by side in a direction of a rotating axis X along an inner peripheral surface of a transmission case. In the second multi-plate brake device, the snap ring is supported by a supporting portion which is formed on the first multi-plate brake device side of the snap ring and protrudes from the inner peripheral surface of the transmission case radially inward to the rotating axis X. The piston retainer of the first multi-plate brake device includes an abutting portion that protrudes to the second multi-plate brake device side and abuts the supporting portion from the opposite side of the snap ring of the second multi-plate brake device. The abutting portion includes a thick portion whose radial thickness on a lower side in a vertical direction is increased as compared to on an upper side in the vertical direction based on a state of mounting the automatic transmission on a vehicle.