Patent ID: 8428838
Filing Date: 2013-04-23
Classification: B60K,F16D,Y10T

Abstract:
1. A driving-force transmitting apparatus for a vehicle capable of switching between a four-wheel drive mode in which distribution of a driving force to be transmitted to front wheels and rear wheels is automatically controlled according to a running condition and a two-wheel drive mode in which the driving force is transmitted only to the front wheels, the driving-force transmitting apparatus comprising: a front-wheel differential device that, upon receiving a driving force from an engine, distributes the driving force to left and right front wheels; a first driving-force transmitting direction converting unit that changes a rotating direction of the driving force from the engine for transmission to the rear wheels; a rear-wheel differential device that distributes the driving force to left and right rear wheels; a second driving-force transmitting direction converting unit that, upon receiving the driving force from the first driving-force transmitting direction converting unit, changes a rotating direction for transmission to the rear-wheel differential device; a disengaging device that disengages the driving force to the first driving-force transmitting direction converting unit; a multi-clutch mechanism provided between one of outputs of the rear-wheel differential device and one of the left and right rear wheels, the multi-clutch mechanism capable of successively adjusting a fastening force; a drag-torque decreasing mechanism that sets drag torque when fastening of the multi-plate clutch mechanism is released to be smaller than friction torque between the first driving-force transmitting direction converting unit and the second driving-force transmitting direction converting unit; and a controller that disconnects the disengaging device and releases the fastening force of the multi-plate clutch mechanism in the two-wheel drive mode to stop rotation of the second driving-force transmitting direction converting unit from the first driving-force transmitting direction converting unit, and connects the disengaging device and adjusts the fastening force of the multi-plate clutch mechanism according to the running condition of the vehicle in the four-wheel drive mode, wherein the rear-wheel differential device and the multi-plate clutch mechanism are separated from each other as different units so that lubricating oil of the rear-wheel differential device and lubricating oil of the multi-plate clutch mechanism do not mix together.