Abstract: A continuously variable transmission (2) has a first helical gear (204A) for its rotation output. The fixed speed ratio transmission (3) has a second helical gear (203B) for its rotation output. The third helical gear (207) rotates according to the difference of the rotation speeds of the first helical gear (204A) and second helical gear (203B). These helical gears rotate on a same rotation shaft (204). One of the three helical gears positioned between the other two helical gears applies a bending moment on the rotation shaft (204) due to a radial force given by a gear meshed therewith. The direction of the tooth trace of the other two helical gears is set so that at least one of them produces a bending moment in an opposite direction to the first bending moment.