Abstract: Aiming at the problem of poor assembly quality stability and low efficiency which caused by manual assembly operation of tilt hydraulic cylinder, a full-automatic equipment for assembling tilt hydraulic cylinder was designed. Firstly, the assembly structure of tilt hydraulic cylinder was analyzed, and then the overall process and structure scheme of the full-automatic equipment were studied and designed, then the failure mode of the full-automatic equipment was studied by design failure mode effects analysis (DFMEA)， process failure modes and effects analysis (PFMEA) tools. The control system of the full-automatic equipment was designed with PLC as control core, which included the hardware circuit design, the servo control subsystem design, the control system program flow design and the upper-computer software design. Finally, the fully automatic assembly equipment of tilt cylinder was applied to the actual assembly production site of tilt cylinder to verify the actual working performance of the equipment. The results indicate that the full-automatic equipment can improve the assembly efficiency by 30%, reduce the number of assembly workers by 50%, increase the pass rate of assembly to more than 95%, and effectively improve the stability of assembly.

Key words:  tilting cylinder;assembly equipment;failure mode;control system;mechanism optimization