Patent ID: 9695883
Date: 2017-07-04
CPC Classifications: F16D

Claim:
1. A clutch device including, a clutch outer and a clutch inner coaxially supported on a rotating shaft, outer friction plates held by engagement with the clutch outer, and inner friction plates held by engagement with the clutch inner, for switching between transmission and non-transmission of power between the clutch outer and the clutch inner by bringing the outer and inner friction plates into pressure contact with one another in a clutch axial direction or releasing the pressure contact therebetween, the clutch device comprising: a clutch piston that is supported movably in the clutch axial direction by the clutch inner and brings the outer and inner friction plates into pressure contact with one another in cooperation with a supporting portion of the clutch inner; a pressure ring that moves the clutch piston with a force toward a clutch connected position, the force toward the clutch connected position bringing the outer and inner friction plates into pressure contact with one another; a clutch spring that is disposed between the pressure ring and the clutch piston and transmits the force toward the clutch connected position from the pressure ring to the clutch piston; and a return spring that is disposed between the clutch inner and the clutch piston and urges the clutch piston toward a clutch disconnected position with a force smaller than that of the clutch spring, wherein the clutch spring and the return spring are disposed parallel to the clutch axial direction, wherein a plane perpendicular to an axis of the clutch passes through the clutch spring and the return spring, wherein the clutch inner has a cylindrical wall that supports the inner friction plates, the cylindrical wall being provided with a notch serving as a receiving portion of the return spring, and wherein the clutch piston is provided with a detent, the detent engaging in a non-relatively-rotatable manner an end of the notch on a side on which the clutch piston is located, and wherein the clutch piston has an inner supporting portion that protrudes coaxially toward the clutch inner, the inner supporting portion including