A Study on Insert Injection Molding for BLDC Motor Stator

BLDC 모터 고정자의 인서트 사출 성형에 관한 연구

  • Received : 2015.07.31
  • Accepted : 2015.09.11
  • Published : 2015.09.30


Insert injection molding is a process in which molten plastic is injected into a mold that contains a pre-placed insert. During the injection stage, the insert can be deformed by the pressure applied by the polymer melts. The deformation of the insert changes the width of the flow path around the insert, which can cause several defects such as short shots or warpages of the parts. In order to reduce the deformation of the insert, it is important to achieve successful design of gating system, insert geometry, and molding conditions. In the present study, the insert deformations that occured during the injection molding of the BLDC motor stator were investigated by numerical analyses. The gate location and the insert shape were modified to reduce the insert deformation. Finally, the injection molding with the modified designs was carried out, and it was confirmed that the insert deformation was reduced.


BLDC motor;Insert deformation;Injection molding


  1. T. J. Lho, K. S. Kim, "A Study on Implementation of Al-Inserted Plastic Injection Molding Process for Automobile Interior-Parts," Journal of the Korean Society for Precision Engineering, Vol. 25, No. 5, pp. 43-51, 2008.
  2. H. L. Chen, S. C. Chen, W. H. Liao, R. D. Chien, Y. T. Lin, "Effects of insert film on asymmetric mold temperature and associated part warpage during in-mold decoration injection molding of PP parts," International Communications in Heat and Mass Transfer, Vol. 41, pp. 34-40, 2013. DOI:
  3. D. G. Ahn, D. W. Kim, "Injection Molding Analysis of Battery case considering the Insert Deformation," Proc. of the KSME Autumn, pp. 1107-1112, November, 2008.
  4. Matt Jaworski, Simulation of Core Shift and Injection Molding Machine Clamp Over - Tonnage Using Moldflow Plastic Insight, Moldflow Pty. Ltd., pp.2-12, 2005.