Abstract: In order to optimize the backlash of the RV reducer, the factors affecting the backlash are classified from the angle of the part error based on the two stage structure and the torque transmission path of the RV reducer. Taking the RV-40E reducer used in industrial robot as an example, the sensitivity and weight of the backlash are calculated. Among them, the cycloidal gear profile modification has large sensitivity. In order to reduce the gear side clearance caused by the cycloid gear modification, a modification method of the cycloidal gear tooth profile based on the compensation of deformation is proposed. On the basis of equidistant & radial-moving modification, the deformation of the pin gear at rated load is compensated for the cycloidal gear tooth profile. The backlash optimization of the RV reducer is realized without changing the radial clearance of cycloidal drive. The virtual prototype of RV-40E reducer is set up, and the simulation verification is carried out in the SolidWorks Motion. The results show that, with the optimization of backlash, the backlash of virtual prototype is 0.25 '~0.98', which is lower than that of the virtual prototype with equidistant & radial-moving modification (0.54 '~1.22'). The cycloidal gear tooth profile modification method based on the compensation of deformation can significantly reduce the backlash of the RV reducer.

Key words: RV reducer, backlash, cycloidal gear, tooth profile modification, backlash simulation