Abstract: A model was established to describe the wear characteristics of toggle mechanism in clamping units of precise injection molding machines. The corresponding calculation formula was derived, and the influence of various parameters on wear life of toggle mechanism was analyzed. The research showed that the wear of toggle mechanism mainly occurs on the frictional interface of interfacial material, equivalent elastic modulus, wear constant, load, structure parameters of pin and sleeve. It also showed that the wear rule of pin and sleeve were different from conventional friction pairs: the clearance between pin and sleeve had great influence on the wear life of toggle mechanism, however, the radius of pin had little influence on it, and it was a power function between the wear life and the clamp force.

Key words: injection molding machine, clamping unit, toggle mechanism, wear