Patent attributes
In a friction engagement device of an automatic transmission, a brake piston is actuated by an oil pressure and a friction disc is pressed by the brake piston. The friction engagement device of an automatic transmission includes an oil pressure chamber extending in an annular shape and a main oil pressure supply path and a secondary oil pressure supply path each extending separately to supply oil to the oil pressure chamber. Each of the main oil pressure supply path and secondary oil pressure supply path connects to the oil pressure chamber in a position different from each other in a circumferential direction of the oil pressure chamber. With a construction as such, a friction engagement device of an automatic transmission is provided which prevents a load to the friction disc from locally increasing and attains a smooth speed-changing operation.
