Patent ID: 8037779

Claim:
A speed change control device of a vehicular transmission in which shift forks for selectively establishing gear trains of a plurality of speed change stages arranged between main shafts transmitted with power from an internal combustion engine and a countershaft connected to drive wheels are engaged with lead grooves formed on an outer periphery of a shift drum, and in which a driving means including an electric motor and rotatably driving the shift drum with power exerted by the electric motor is connected to the shift drum; wherein the driving means includes, the electric motor having a rotation axis in a plane orthogonal to an axis of the shift drum; a barrel cam that rotates about an axis parallel to the electric motor by power transmission from the electric motor and that has a cam groove formed on an outer periphery; and a transmission rotation member interlocked and coupled to the shift drum so as to be rotatable about an axis orthogonal to the rotation axis of the barrel cam and arranged with a plurality of engagement pins that selectively engages the cam groove.