Patent ID: 9057438
Filing Date: 2015-06-16
Classification: F16H

Abstract:
1. A compression control device for a continuously variable transmission, comprising: an input shaft to which a driving force of a drive source is inputted; an input shaft element that is provided on the input shaft; an output shaft via which the driving force of the drive source is changed in speed and outputted; an output shaft element that is provided on the output shaft; a power transmission element that is in contact with each of the input and output shaft elements and transmits the driving force from the input shaft to the output shaft by friction in contacting portions; torque ratio estimation means that estimates a torque ratio, which is the ratio of an actually transmitted torque relative to a maximum transmittable torque, based on characteristics of transmission of a given variable component of the input shaft to the output shaft; compression control means that controls compression of either one shaft element of the input and output shaft elements; and coefficient of friction estimation means that estimates a coefficient of friction between said either one shaft element and the power transmission element, wherein the torque ratio estimation means estimates the torque ratio from at least one of a slip identifier, which is an indicator for the ratio of an amplitude of the variable component between the input shaft and the output shaft, and a phase lag, which is an indicator for difference in phase of the variable component between the input shaft and the output shaft, the coefficient of friction estimation means estimates the coefficient of friction based on the torque ratio, the compression control means determines a necessary axial thrust of said either one shaft element based on the coefficient of friction and controls the compression of said either one shaft element based on the necessary axial thrust, and wherein the device comprises load torque estimation means that estimates a load torque of the drive source, and the coefficient of friction estimation means estimates the coefficient of friction based on the load torque and the axial thrust of said either one shaft element.