METHOD OF CONTROLLING SPEED CHANGING RATE FOR METAL BELT TYPE NON-STAGE TRANSMISSIONS

摘要

A metal belt type non-stage transmission, wherein a change gear ratio (i) is changed by applying a first large axial thrust to a drive pulley and a second small axial thrust to a driven pulley at a shift-up time, and thereby increasing a passed-around radius of the drive pulley, the feed-forward controlling of the first axial thrust being done on the basis of a target speed changing rate (dR/ds) in a region (B) in which the relation between a speed changing rate (dR/ds), which is defined as a value obtained by differentiating the passed-around radius (R) of the drive pulley, by a tangential amount of movement (s) of a metal belt and the first axial thrust is maintained substantially linearly, the feed-back controlling of the first axial thrust being done so that the speed changing rate (dR/ds) agrees with the target speed changing rate (dR/ds) in regions (A, C) in which the relation between the speed changing rate (dR/ds) and the first axial thrust is not maintained substantially linearly.