| 摘要 |
PROBLEM TO BE SOLVED: To prevent troubles such as that a vehicle consumes a battery before it arrives at an area where a four-wheel driving function is required such as a snowfall district, etc., and that it becomes unable to use four-wheel drive at a necessary moment. SOLUTION: A four-wheel driver has a prime mover 3 for rotating a first wheel drive shaft 1, a motor 14 for rotating a second wheel drive shaft 2, a prime mover control means 5, an accumulator 15 for operating the motor 14, a means 25 for detecting the residual quantity of the accumulator 15, and a motor control means 16. The four-wheel driver drives a vehicle usually using the first wheel drive shaft on one hand and generates driving force in the second wheel drive shaft 2 on the other by giving objective drive torque to the motor control means 16, based on the request of the four-wheel drive. Further, the driver is equipped with a navigation system 19 which computes the recommended traveling course from the present position to the destination, and an environment information acquisition means 25 which gets the environmental information on the recommended traveling course. The objective drive torque of the second wheel drive shaft is decided depending upon the present residual quantity of the accumulator 15 and the environmental information on the recommended traveling course form the present position to the destination. |
