Abstract: In order to make COMAS case tipper adapt to worn tobacco case handling and reduce emergency stop, its clamping mechanism was analyzed and modified. Via increasing the diameter of air bag, adjusting the height and width of the clamper base, modifying the shapes and sizes of the air inlet seat and plug, and connecting the wear strip and the air bag, tobacco cases were clamped and fixed by the clamper tightly. By means of adding a lateral position limiting device, the lateral positional deviation of tobacco cases was avoided. The COMAS case tipper before and after modification was comparatively tested on 3 production lines, the results showed that after the modification, the emergency machine shutdown of COMAS case tipper was reduced by 9.0 times/month, the troubleshooting time was shortened by 11.8 min/time, and the cost for tobacco case maintenance was saved by 778 thousand RMB yuan per year. This technology provides a support for promoting the equipment operating efficiency of primary processing line.