Patent ID: 7278939

Claim:
A power transmission equipped with a continuously variable ratio-change mechanism and a fixed ratio rotational transmission mechanism, which transmit a rotational driving force of an input shaft rotationally driven by a drive source to an output shaft with a speed ratio change; wherein: said continuously variable ratio-change mechanism transmits a rotation from said input shaft to a middle shaft at a continuously variable speed change ratio; and said fixed ratio rotational transmission mechanism comprises a first rotational transmission gear train, a second rotational transmission gear train and a third rotational transmission gear train, said first rotational transmission gear train transmitting the rotation of said input shaft to said middle shaft, said second rotational transmission gear train transmitting the rotation of said middle shaft to said output shaft, and said third rotational transmission gear train transmitting the rotation of said input shaft to said output shaft without said middle shaft, and wherein said continuously variable ratio-change mechanism and said fixed ratio rotational transmission mechanism are disposed in parallel with one another and are selectively used for transmitting rotational force from the input shaft to the output shaft.