Patent ID: 6049750
Filing Date: 2000-04-11
Classification: F16H,Y10T

Abstract:
A speed change ratio controller for a continuously variable transmission of a vehicle, said transmission having a V-belt looped around a pair of variable pulleys, said pulleys varying a radius of a contact part with the V-belt according to a first oil pressure supporting anyone of said pulleys and a second oil pressure supporting the other of said pulleys, said controller comprising:a sensor for detecting a running state of a vehicle,a sensor for detecting a real speed change ratio of said transmission,an oil pressure supply unit for generating said first oil pressure, said first oil pressure varying according to said running state,a speed change control valve for adjusting the first oil pressure to the second pressure according to a speed change ratio command value,means for setting a target speed change ratio from said running state,means for calculating the first oil pressure based on said running state of the vehicle,means for estimating a dynamic characteristic of said transmission for each real speed change ratio of said transmission and for each value of the first oil pressure, andmeans for computing said speed change ratio command value based on said target speed change ratio and said dynamic characteristic.