English to French Tech/Engineering Law: Patents, Trademarks, Copyright Driving force transmission device for four-wheel-drive vehicle

Fig. 15 is a cross sectional view showing another embodiments of the driving force distribution device 18 in Fig. 3. and the configuration is same as that shown in Figs. 5 and 6 except that a ball cam mechanism 122 is different.
In Fig. 16. a servo motor 150 rotates a fringe cam 198 through a reduction gear 152. In the rotation cam plate 126, a cam follower 196 consisting of a rotatable roller is provided on the end of an expanded arm unit 144, and the cam follower 196 contacts the external circumferential part of the fringe cam 198. When the rotation cam plate 126 is driven to rotate to the fixed cam plate 124 in the specified direction by the fringe cam 198, the ball cam mechanism 122 receives the press by the ball 140 sandwiched between the ball cam grooves 128 which are the inclined grooves of the facing surfaces and presses the press member 160 and a return spring 162 in the axial direction, and the press member 160 presses the clutch discs 120 of the multi-disc clutch mechanism 106, thereby the ball cam mechanism increases the transmission torque depending on the rotation amount of the drive gear 148, therefore it becomes direct connection state at the maximum press position.

Figs. 16A and 16B are explanatory diagrams showing the ball cam mechanism 122 in Fig. 15 viewed from the axial direction of the input shaft 102. In Figs. 16A and 16B, the rotation cam plate 126 includes the ball cam grooves 128 in the circumferential direction. The ball cam grooves 128 in the present embodiment do not have a runover unit 134 as shown in Figs. 14A to 14C in the embodiment of Fig. 3, and the inclined area 132 has a shape that goes without a step from the initial area 130. The external circumferential part of a cam follower 196 provided on the end of an arm unit 144 expanding from the rotation cam plate 126 contacts the cam surface of a fringe cam 198. The cam surface of the fringe cam 198 consists of an initial area 200, a nonlinear area 202 and a linear area 206, and the fringe cam 198 rotates clockwise to drive and rotate the rotation cam plate 126 through the cam follower 196, and 5 presses the multi-disc clutch mechanism 106.