Abstract: A fastening portion is formed from a rivet hole of a first side wall portion of a clutch drum, a rivet hole of a second side wall portion of a clutch drum, and a rivet that is inserted into the rivet hole and the rivet hole to hold together the first side wall portion and the second side wall portion. The fastening portion is provided between a first engagement side oil chamber enclosed by the clutch drum and a clutch piston, and a second engagement side oil chamber enclosed by the clutch drum and a clutch piston.

Abstract: A hydraulic clutch including a clutch drum with an outer cylinder fitted with a plurality of clutch plates and a side wall; a clutch piston that defines together with the clutch drum an engagement oil chamber, and moves in an axial direction to press the clutch plates by hydraulic pressure supplied to the engagement oil chamber; and a cancel plate that defines together with the clutch piston a cancel oil chamber that cancels centrifugal hydraulic pressure. The side wall of the clutch drum is formed with a first oil passage that radially extends and is in communication with the engagement oil chamber, and a second oil passage that radially extends and is in communication with the cancel oil chamber. One of the first and second oil passages is at least partially included in a range of an axial width of the other of the first and second oil passages.

Abstract: A hydraulic clutch including a clutch drum with an outer cylinder fitted with a plurality of clutch plates and a side wall; a clutch piston that defines together with the clutch drum an engagement oil chamber, and moves in an axial direction to press the clutch plates by hydraulic pressure supplied to the engagement oil chamber; and a cancel plate that defines together with the clutch piston a cancel oil chamber that cancels centrifugal hydraulic pressure. The side wall of the clutch drum is formed with a first oil passage that radially extends and is in communication with the engagement oil chamber, and a second oil passage that radially extends and is in communication with the cancel oil chamber. One of the first and second oil passages is at least partially included in a range of an axial width of the other of the first and second oil passages.

Abstract: A hydraulic clutch including a clutch drum with an outer cylinder fitted with a plurality of clutch plates and a side wall; a clutch piston that defines together with the clutch drum an engagement oil chamber, and moves in an axial direction to press the clutch plates by hydraulic pressure supplied to the engagement oil chamber; and a cancel plate that defines together with the clutch piston a cancel oil chamber that cancels centrifugal hydraulic pressure. The side wall of the clutch drum is formed with a first oil passage that radially extends and is in communication with the engagement oil chamber, and a second oil passage that radially extends and is in communication with the cancel oil chamber. One of the first and second oil passages is at least partially included in a range of an axial width of the other of the first and second oil passages.

Abstract: A transmission device includes a first clutch and a second clutch that is disposed circumferentially inward of the first clutch so as to overlap with the first clutch as viewed from a radial direction. The first clutch includes a first clutch drum, a first clutch piston that is axially movable by hydraulic pressure supplied to a first engagement side oil chamber on an inner circumferential side of the first clutch drum, and a first cancel plate that defines together with the first clutch piston a first cancel oil chamber that cancels centrifugal hydraulic pressure. The first cancel plate is fastened between the first clutch drum and a second clutch drum of the second clutch.

Abstract: A fastening portion is formed from a rivet hole of a first side wall portion of a clutch drum, a rivet hole of a second side wall portion of a clutch drum, and a rivet that is inserted into the rivet hole and the rivet hole to hold together the first side wall portion and the second side wall portion. The fastening portion is provided between a first engagement side oil chamber enclosed by the clutch drum and a clutch piston, and a second engagement side oil chamber enclosed by the clutch drum and a clutch piston.

Abstract: An automatic transmission includes first and second clutches disposed adjacent, wherein each of the first and second clutches includes a friction plate; a clutch drum in spline engagement with the friction plate; a piston that with the clutch drum forms a hydraulic oil chamber therebetween; a return spring that biases the piston toward the hydraulic oil chamber side; and a cancel plate that is disposed on a side opposite the hydraulic oil chamber of the piston to form a cancel oil chamber that cancels outs a centrifugal hydraulic pressure that acts on the hydraulic oil chamber, and that receives a reaction force of the return spring.

Abstract: A transmission device includes a first clutch and a second clutch that is disposed circumferentially inward of the first clutch so as to overlap with the first clutch as viewed from a radial direction. The first clutch includes a first clutch drum, a first clutch piston that is axially movable by hydraulic pressure supplied to a first engagement side oil chamber on an inner circumferential side of the first clutch drum, and a first cancel plate that defines together with the first clutch piston a first cancel oil chamber that cancels centrifugal hydraulic pressure. The first cancel plate is fastened between the first clutch drum and a second clutch drum of the second clutch.

Abstract: A hydraulic clutch including a clutch drum with an outer cylinder fitted with a plurality of clutch plates and a side wall; a clutch piston that defines together with the clutch drum an engagement oil chamber, and moves in an axial direction to press the clutch plates by hydraulic pressure supplied to the engagement oil chamber; and a cancel plate that defines together with the clutch piston a cancel oil chamber that cancels centrifugal hydraulic pressure. The side wall of the clutch drum is formed with a first oil passage that radially extends and is in communication with the engagement oil chamber, and a second oil passage that radially extends and is in communication with the cancel oil chamber. One of the first and second oil passages is at least partially included in a range of an axial width of the other of the first and second oil passages.

Abstract: An automatic transmission includes first and second clutches, a clutch drum, a piston, a plurality of friction plates, a hydraulic oil chamber, a cancel oil chamber, a return spring, and a cancel plate, wherein a plate member that forms a cylinder portion of the hydraulic oil chamber is provided between the piston and the clutch drum of the first clutch that is located on an inner diameter side, and an oil passage that supplies an oil to the cancel oil chamber of the second clutch that is located on an outer diameter side is formed between the clutch drum and the plate member.

Abstract: An automatic transmission includes first and second clutches disposed adjacent, wherein each of the first and second clutches includes a friction plate; a clutch drum in spline engagement with the friction plate; a piston that with the clutch drum forms a hydraulic oil chamber therebetween; a return spring that biases the piston toward the hydraulic oil chamber side; and a cancel plate that is disposed on a side opposite the hydraulic oil chamber of the piston to form a cancel oil chamber that cancels outs a centrifugal hydraulic pressure that acts on the hydraulic oil chamber, and that receives a reaction force of the return spring.

Abstract: An automatic transmission includes first and second clutches, a clutch drum, a piston, a plurality of friction plates, a hydraulic oil chamber, a cancel oil chamber, a return spring, and a cancel plate, wherein a plate member that forms a cylinder portion of the hydraulic oil chamber is provided between the piston and the clutch drum of the first clutch that is located on an inner diameter side, and an oil passage that supplies an oil to the cancel oil chamber of the second clutch that is located on an outer diameter side is formed between the clutch drum and the plate member.