Patent ID: 8989979
Filing Date: 2015-03-24
Classification: B60K,B60W,B60Y

Abstract:
1. A control unit for a four-wheel-drive vehicle, the control unit being mounted in the four-wheel-drive vehicle, the four-wheel-drive vehicle comprising: a dog clutch that is able to switch a drive mode between a four-wheel-drive mode, in which driving force is transmitted from a drive source to main drive wheels and auxiliary drive wheels, and a two-wheel-drive mode, in which the driving force is transmitted from the drive source only to the main drive wheels, and that allows transmission of the driving force from the drive source to the auxiliary drive wheels by engaging a first rotary member arranged on a drive source side and a second rotary member arranged on an auxiliary drive wheel side with each other, and interrupts transmission of the driving force from the drive source to auxiliary drive wheels by disengaging the first rotary member and the second rotary member from each other; and a traction control unit that controls at least one of the driving force that is generated by the drive source and braking force that is applied to the main drive wheels to suppress a slip of the main drive wheels, wherein the control unit for the four-wheel-drive vehicle detects a relative rotational speed between the first rotary member and the second rotary member of the dog clutch when the drive mode is being switched from the two-wheel-drive mode to the four-wheel-drive mode and, only when the detected relative rotational speed between the first rotary member and the second rotary member of the dog clutch is equal to or higher than a predetermined value, outputs a command signal to the traction control unit to execute control for suppressing the relative rotational speed between the first rotary member and the second rotary member of the dog clutch.