DRIVING FORCE DISTRIBUTION SWITCHING TYPE FOUR-WHEEL DRIVE AUTOMOBILE

PURPOSE:To prevent the generation of a spin so as to improve the travel limit by detecting yaw angle acceleration, and performing the specified driving force distribution when the detected yaw angle acceleration is less than the specified threshold value, whereas increasing the driving force distribution on the front wheel side when the yaw angle acceleration is more than the threshold value. CONSTITUTION:A steering angle theta from a steering sensor 30, lateral acceleration G1, G2 from a front and a rear lateral acceleration sensors 34A, 34B, and the detection signals of a longitudinal acceleration sensor 36 and the like are inputted into a controller 48. The yaw angle acceleration computing part 48a of the controller 48 computes yaw angle acceleration gamma' on the basis of the lateral acceleration G1, G2, and a comparing/judging part 48b compares the computed yaw angle acceleration gamma' with the threshold value gamma'0. At the time of gamma' gamma'0, however, an output part 48c controls a multiple disc clutch 28 through a pressure control valve 56 so as to increase distribution on the front wheel side. The generation of a spin can be thus prevented positively.