Abstract:In order to study the influencing factors of frictional torque of crossed roller bearings,a calculation model of bearing frictional torque considering the influence of ambient temperature and temperature rise was established,and the influence of working conditions,ambient temperature and geometric parameters on the frictional torque of the bearing was studied,and the test was verified.The results show that when the crossed roller bearing only bears axial load,the frictional moment is mainly generated by one of the contact pair;when the crossed roller only bear radial load or overturning moment,the ratio of frictional torque generated by the two contact pairs is 1∶1.In the range from -30 ℃ to 50 ℃,the ambient temperature rises,the frictional torque of the bearing first decreases and then increases.When the temperature is less than 40 °C,the viscosity of the grease plays a leading role in the total friction torque,the influence of clearance change is second;when the temperature is at 50 °C,the clearance change plays a leading role in the friction torque,and the influence of grease viscosity is second.Increasing the radial clearance can significantly reduce the bearing frictional torque.Among the three modification methods of straight busbar,logarithmic modification and full convex circular arc modification,the effect of full convex circular arc modification is more significant in reducing frictional torque under a wide range of load conditions.