Power transmitting system in four-wheel drive vehicle

摘要

A hydraulic coupling device includes left and right vane pumps which discharge working oil in response to the relative rotation of main driven wheels and left and right subsidiary driven wheels. First orifices are defined in a side plate disposed between the left and right vane pumps to permit communication between intake ports and discharge ports in the vane pumps. Orifices are defined in the side plate to permit communication between the intake ports and between the discharge ports in the vane pumps. With the above arrangement, in a hydraulic coupling device of a power transmitting system in a four-wheel drive vehicle, the formation of the orifices can be easily carried out, and the characteristics of the orifices can be stabilized. <IMAGE>