Mold temperature plays a significant role to the quality of injection molding process. A high mold temperature setting is feasible to enhance the molding quality but prolongs the cooling time. Use of induction heating to heat the mold surface only seems to provide a feasible solution without scarifying the molding cycle. Still, there exist some problems to be resolved in induction heating such as proximity effect. The proximity effect is the sudden interaction of magnetic fields that are generated because of two nearby coils with inverse current directions, affecting the change of flux. It causes significant decrease of heating efficiency and thereby generates non-uniform heating. To eliminate its drawback, this study proposes a novel magnetic shielding induction heating method by employing ferrite materials to enhance both the heat efficiency and uniformity. Comparing to conventional magnetic concentrator, experimental results depict that the proposed method can efficiently improve the influence of proximity effect; thus increases heating rate and obtains more uniform temperature distribution.
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