摘要
Abstract
A fire sensor face cover features three inner undercut regions and an 18° inclined flanged edge,which leads to severe difficulties in direct demolding during injection molding.To solve this problem,a dual-cavity injection mold equipped with a novel composite angled slider sequential core-pulling mechanism was proposed in this work.The target plastic part has an average wall thickness of 3 mm,overall dimensions of 143×34×44 mm3,and a volume of 34.3 cm3.A PC/ABS alloy was selected as the molding material to satisfy the requirements of flame retardancy and mechanical per-formance.The core difficulty of the mold design lies in the coordinated demolding of multiple internal undercut struc-tures.To address this issue,the molding inserts corresponding to the three undercuts were designed as three independent sliding blocks,which were integrally assembled on a shared carrier slider to realize synchronous cooperative motion.The overall demolding procedure was divided into two sequential stages.In the early mold-opening stage,an angled lifter drives the primary slider to complete the initial inclined core-pulling at an angle of 20° relative to the horizontal plane.Meanwhile,the secondary and tertiary sliders are actuated by springs to implement lateral core-pulling with a stroke of 18 mm in two opposite horizontal directions.Afterwards,a delayed angled lifter pushes the carrier slider together with all three sliders to integrally move along the inclined direction of the first core-pulling action,achieving complete separation between the mold and the plastic part.Moldflow CAE simulation was conducted to verify the rationality of the designed gating and cooling systems.The simulation results show that the single-cavity filling time is 1.54 s,the maximum injec-tion pressure is 45.3 MPa,and the maximum warpage deformation is 1.117 mm.The melt front temperature distribu-tion remains uniform throughout the filling process,the required clamping force is approximately 65 tons,and the risk of weld line defects is well controlled.The developed mold adopts a conventional two-plate structure with single parting sur-face and pin ejection.The proposed composite angled slider mechanism decomposes the complex three-dimensional multi-directional core-pulling motion into stepwise,controllable,and simple sequential movements.关键词
消防感应器面盖/复合斜滑块/顺序抽芯/延时抽芯/模具设计Key words
fire sensor face cover/composite angled slider/sequential core-pulling/delayed core-pulling/mold design分类
化学化工
