Driving-force transmitting apparatus for four-wheel-drive vehicle

摘要

A transmitting apparatus (10) includes a disengaging device (28) that disengages a driving force from a front-wheel differential device (18) to a first driving-force transmitting direction converting unit (20) and a multi-plate clutch mechanism (30) provided between an output of a rear-wheel differential device (26) and a right-rear wheel (82) and capable of successively adjusting a fastening force. Drag torque when the fastening of the multi-plate clutch mechanism (30) is released is set smaller than friction torque of a rear-wheel drive system between the first driving-force transmitting direction converting unit (20) and a second driving-force transmitting direction converting unit (24). A controller (25) unconnects the disengaging device (28) and releases the fastening of multi-plate clutch mechanism (30) when switching to a two-wheel drive mode, thereby stopping the rotation of the rear-wheel drive system.