CONTINUOUSLY VARIABLE TRANSMISSION

摘要

Provided is a traction drive-type continuously variable transmission mechanism having the following: a shaft (60) which functions as the center of rotation; relatively rotatable first and second rotating members (10, 20) which are disposed facing each other upon the shaft (60) and share a first rotation center axis (R1); a plurality of planetary balls (50) which have a second rotation center axis (R2), are radially disposed centered around the first rotation center axis (R1) and held by the first and second rotating members (10, 20); and an iris plate (80) which changes the transmission gear ratio between an engine side input shaft (11) and a drive wheel side output shaft (21) by tilting the planetary balls (50) with respect to the first rotation center axis (R1). When an engine is started, the transmission gear ratio is controlled so as to be on the increased speed side rather than the most reduced speed side.