Patent ID: 7637843
Filing Date: 2009-12-29
Classification: F16H,Y10T

Abstract:
1. A control device for a continuously variable transmission, the continuously variable transmission having a pair of variable pulleys constituted by a primary side pulley and a secondary side pulley, in which a contact pulley width of a V belt is variably controlled on the basis of an oil pressure, and a first speed ratio corresponding to a biggest speed ratio and a second speed ratio that is smaller than the first speed ratio as a startup speed ratio, the control device comprising: a speed change control valve which supplies the variable pulleys with the oil pressure; an actuator which drives the speed change control valve in accordance with a target speed ratio, and have a starting position of which is set at a position in which a speed ratio of the continuously variable transmission reaches the biggest speed ratio; a controller for controlling the speed ratio via the actuator; a shift lever position detecting switch for detecting a position of a shift lever of the continuously variable transmission; and a primary side pulley rotation speed sensor for detecting a rotation speed of the primary side pulley; wherein the controller switches the speed ratio from the second speed ratio to the first speed ratio, when the shift lever position of the continuously variable transmission is in a position for selecting the second speed ratio, vehicle deceleration is underway, and the rotation speed of the primary side pulley falls to a predetermined rotation speed; switches the speed ratio from the first speed ratio to the second speed ratio, when the shift lever position of the continuously variable transmission is in a position for selecting the second speed ratio, vehicle startup is underway, and the rotation speed of the primary side pulley rises to the predetermined rotation speed; and controls the actuator in accordance with the switched speed ratio.