V-belt pinch pressure control device of the V-belt type continuously variable transmission

摘要

PROBLEM TO BE SOLVED: To improve the durability of a V-belt by suitably controlling a line pressure of a V-belt-type variable speed change gear when it is in a state of non-transmission and it is shifted to a state of transmission. ;SOLUTION: A controller 17 determines an aiming input number of revolution N1 from input information and operates a valve 21 with a step motor 23 via a link 22 in response to this. The valve 21 adjusts a control pressure Ps to variably change a transmission ratio between pulleys 1 and 2 to the ratio corresponding to the aiming input number of revolution N1. When the controller 17 controls the original line pressure P1, it determines a duty D for a line pressure solenoid 13 such that the line pressure P1 is set at the minimum value corresponding to a large static friction coefficient between a V-belt 3 and pulleys 1, 2 when a primary pulley number of revolution Npri is zero and that the line pressure P1 is increased to the maximum value corresponding to a small dynamic friction coefficient between a V-belt 3 and pulleys 1, 2 as the Npri is increased.;COPYRIGHT: (C)1997,JPO