Patent ID: 6850830

Claim:
A driving force control system for a four-wheel drive vehicle including a pair of front wheels, a pair of rear wheels, an engine to which one of said pair of front wheels and said pair of rear wheels is connected as main drive wheels, and clutches for connecting another of said pair of front wheels and said pair of rear wheels to said main drive wheels, as auxiliary drive wheels, the driving force control system controlling engagement forces of said clutches to thereby control distribution of a driving force of said main drive wheels to said auxiliary drive wheels, the driving force control system comprising: driving force calculation device for calculating said driving force of said main drive wheels being actually delivered from said engine based on sensed values, including a sensed engine rotational speed, input device being operated by a driver for executing a lock mode; lock-mode engagement force-setting device for setting engagement forces of said clutches for said lock mode, including lockable clutch engagement forces which can lock said main drive wheels and said auxiliary drive wheels to each other depending on said driving force of said main drive wheels calculated by said driving force calculation device, when said input device is operated; and lock mode execution device for executing said lock mode based on the set engagement forces of said clutches for said lock mode when said input device is operated.