A roller clutch 32 includes an outer ring 32a, an inner ring 32b, a roller 32c, a biasing member 32e, a retainer 32d, and a regulating part 322d. The roller 32c is disposed between the inner ring 32b and the outer ring 32a and is movable between a transmitting position and a non-transmitting position. The retainer 32d has a roller holding space 328d holding the roller 32c and a support section 322d supporting the biasing member 32e. The regulating part 322d is configured to regulate the movement of the roller 32c, and resist the biasing force of the biasing member 32e at a predetermined position.本發明使內輪之旋轉確實地傳遞至外輪,防止非意圖之內輪之空轉。本發明之滾軸式離合器32包含外輪32a、內輪32b、滾軸32c、第1彈簧構件32e、保持架32d、及突出部327d。滾軸32c配置於內輪32b與外輪32a之間,可於傳遞位置與阻斷位置之間移動。保持架32d包含保持滾軸32c之滾軸保持空間328d、及支持第1彈簧構件32e之支持部322d。突出部327d係將與第1彈簧構件32e之彈推力相抗之滾軸32c之移動限制於特定之位置。32‧‧‧滾軸式離合器32a‧‧‧外輪32b‧‧‧內輪32c‧‧‧滾軸32d‧‧‧保持架32e‧‧‧第1彈簧構件321a‧‧‧凸部321b‧‧‧卡合面322a‧‧‧凸輪面322d‧‧‧支持部323d‧‧‧外周側壁部324d‧‧‧內周側壁部325d‧‧‧底壁部326d‧‧‧收容部327d‧‧‧突出部(限制部)328d‧‧‧滾軸保持空間X‧‧‧旋轉軸
