Abstract:

In this paper,the transmission principle of the traction drive device under hydraulic pressing was analyzed,and the variations of the traction coefficients of the inner and outer friction pairs with the transmission ratio were explored. Then,a method to analyze the sliding characteristics of the traction drive device was investigated. Moreover,a mathematical model and a method to investigate the transmission traction characteristics were proposed based on the elasto-hydrodynamic lubrication theory,which were then used to explore the power characteristics of the friction pairs under different slide-roll ratios and normal pressing forces and to obtain the input and output powers at different total sliding rates. The results show that (1) at a constant sliding rate,the transmission power of the traction drive device under hydraulic pressing increases with the normal pressing force and tends to a constant when the shear stress approaches the ultimate value; (2) under a constant normal pressing force,the transmission power first increases and then decreases with the increase in the sliding rate; and (3) at a constant transmission power,the sliding rate decreases with the increase in the normal pressing force,which may result in high transmission efficiency.

Key words: traction drive, elasto-hydrodynamic lubrication theory, traction coefficient, sliding characteristic, transmission efficiency