Problem to be solved: to reliably separate the friction plate on the driving side and the friction plate on the driven side when the multi plate friction engagement mechanism is changed to the released state.The friction plate 32 on the driving side and the friction plate 31 on the driven side are alternately disposed, and there is provided a multi plate friction engagement mechanism 24 capable of switching relative to the engagement state for restricting the relative rotation between the friction plate 32 on the driving side and the friction plate 31 on the driven side, and an unlocking state to permit the relative rotation, and the following Between the friction plates 32 on the driving side, the friction plate 32 on the driving side and the friction plate 31 on the driven side are allowed to be in contact with each other, and the adjacent friction plates 31 on the driven side are separated from each other in the engagement releasing stateAn elastic member 43 is provided to urge it.Diagram【課題】多板摩擦式係合機構が係合解除状態に切り換わったときに、駆動側の摩擦板と従動側の摩擦板とを確実に分離させることが望まれている。【解決手段】駆動側の摩擦板32と従動側の摩擦板31とが交互に配設され、且つ、駆動側の摩擦板32と従動側の摩擦板31との相対回転を規制する係合状態と、相対回転を許容する係合解除状態とに切り換え自在な多板摩擦式係合機構24が備えられ、隣り合う駆動側の摩擦板32同士の間に、係合状態において駆動側の摩擦板32と従動側の摩擦板31との接触を許容し、且つ、係合解除状態において隣り合う従動側の摩擦板31同士を離間させるように付勢する弾性部材43が備えられている。【選択図】図3
