Abstract: In order to increase metal belt transmission efficiency and improve fuel economy of vehicles with continuous variable transmissions, slip characters are researched. A test bench for metal belt slip characters is created and through test bench experiment, the relationship between slip rate and friction coefficient under conditions of different ratio, different clamp force, and different primary speed is researched. The results are as follows. In the forehead part of slip rate region, friction coefficient increases sharply with increase of slip rate. In the back part of slip rate region, friction coefficient changes little and has decreasing trends; Ratio impacts the slip characters significantly, when ratio is smaller, friction coefficient becomes larger; Impacts from clamp force and primary speed can be ignored. Based on experimental results of slip characters, the definition of object slip region is presented as slip efficiency limit region and slip abrasion limit region. The basis for developing high efficient clamp force control algorithm is provided and a new way to improve transmission efficient of metal V-belt is found out.

Key words: friction coefficient, metal V-belt, slip characters, slip rate