Research On Geometrical Characteristics Of Wire Rope CVT Steel Wire Contact Wear Scars

Metal Belt Continuously Variable Transmission(MB-CVT)is a key technology in automobile transmission system,which meets the national requirements for energy saving and reduction of environmental pollution,and is widely used at home and abroad.Metal belt is the core component of MB-CVT,and its production technology has long been monopolized by foreign companies.In order to break the current situation,the team proposed a new type of continuously variable transmission—Wire Rope Continuously Variable Transmission(WR-CVT)to promote the process of localization of passenger car continuously variable transmission.This paper rely on the open fund project of the State Key Laboratory of Mechanical Transmission "Research on Fretting Wear Mechanism of Steel Rope Ring of Automobile New Type Continuously Variable Transmission"(Grant No.SKLMT-KFKF-201810),comprehensively using mechanics,friction and wear related theories,finite element analysis and experimental methods to study the characteristics of steel wire wear marks.Based on the analysis of the basic structure and working principle of WR-CVT,the force balance equations of the straight section of the rope loop,the bending section and the internal steel wire are established.In the WR-CVT transmission process,the steel rope ring bears various forces,causing friction and wear at the contact position between the steel wires.According to the twisting method of the steel rope loop,the cross type of the steel wire is divided into straight cross,straight-arc cross,combining with the model of the amount of wear between the loop wires of the steel rope,the calculation and error analysis of the wear scar characteristics under different crossing angles are carried out.According to the actual parameters and load-bearing characteristics of the rope loops,the ABAQUS software is used to carry out the finite element analysis of the contact wear scars between the wire ropes,and to explore the evolution law of the wear scar geometry characteristics under different contact angles in terms of wear scar depth,area and volume.Based on this,the friction and wear experiment of the steel rope ring under the actual working conditions of WR-CVT is carried out,and the steel rope ring after the experiment is split,and the wear scar morphology is observed and analyzed by the optical microscope.Analyze the evolution of the geometric characteristics of the wear scar and the degree of wear of the steel wire under different contact angles,the results show that with the increase of the contact angle,the long axis size of the wear scar shows a downward trend,the short axis size shows an upward trend,and the wear scar area shows a downward trend.All have the same trend as the finite element results.It provides a theoretical basis for the optimization of the WR-CVT steel rope loop structural and the microstructure evolution of the wear surface of the steel wire.