Abstract: The analysis of motion and mechanical property was carried out on a force increasing mechanism of injection machine which was five hinged incline arranged and double elbowed. A complete optimization design procedure was carried out using genetic simulated annealing algorithms, so as to increase the stroke ratio and the amplification of the force, and to decrease the total length of mechanism. Its optional mathematics model was established. The procedure of optimal design belongs to multiobject optimization problem. The optimal solution of the force increasing mechanism was found with genetic simulated annealing algorithms. Compared with the traditional methods, the stroke ratio was increased by 5.97 %, the amplification of the force increased by 14.10 %, and the total length of mechanism decreased by 5.25 %.

Key words: Optimal design, force increasing mechanism, injection machine, genetic simulated annealing algorithms, stroke ratio