Patent ID: 8839929

Claim:
A hydraulic clutch comprising: a clutch drum that includes an outer cylinder portion that slidably holds a plurality of clutch plates, a side wall portion that extends radially inward from the outer cylinder portion, and an inner cylinder portion that axially extends from an inner circumferential side of the side wall portion; a sleeve fitted inside the inner cylinder portion of the clutch drum; a clutch piston that is axially movable by hydraulic pressure inside the clutch drum and presses the clutch plates; and a cancel plate that together with the clutch piston defines a cancel oil chamber that cancels centrifugal hydraulic pressure, wherein the cancel plate and an outer circumferential surface of the inner cylinder portion of the clutch drum are sealed, an oil passage that is in communication with the cancel oil chamber is formed on an inner circumferential surface of the inner cylinder portion of the clutch drum, one end surface of the sleeve contacts a stepped portion formed on the inner cylinder portion of the clutch drum, and the sleeve includes a first passage that is in communication with the oil passage of the inner cylinder portion of the clutch drum and formed on an outer periphery of the sleeve so as to axially extend toward the end surface, and a second passage that is axially recessed from the end surface of the sleeve, the second passage radially extending so that the second passage connects the first passage and an inner portion of the sleeve, the second passage being configured to discharge air from the cancel oil chamber.