Design of large and precision injection mold for car rearview mirror substrate

doi:10.19491/j.issn.1001-9278.2025.09.020

Abstract

Abstract:

To meet the structural requirements of a car rearview mirror bracket， characterized by high dimensional accuracy， complex geometry， large lateral buckle size， and directional tilt， a large， high⁃precision， and complex injection mold was designed. In this mold， a fixed⁃mold spring block mechanism was used to prevent sticking between the fixed mold and molded parts. A near⁃conformal water temperature control system was designed to eliminate weld lines and part deformation. An increased slider safety distance was designed to avoid collisions during demolding. The mold achieved a successful first trial， operating smoothly in production with molded parts meeting MT2 precision （GB/T14486—2008）. The injection cycle was reduced by 10 % to 30 s， demonstrating the mold’s advanced， scientific， and innovative design.

Key words: rearview mirror substrate, Large and precise injection molds, spring block of fixed modulus, temperature control system, side core pulling mechanism

CLC Number:

TQ320.66⁺2

YANG Fan, ZHANG Weihe. Design of large and precision injection mold for car rearview mirror substrate[J]. China Plastics, 2025, 39(9): 129-133.

Figures/Tables 9

Fig.1. Car rearview mirror substrates

Fig.2. The gating system of mold

Fig.3. The stereogram of mold formed parts

Fig.4. The spring block of fixed modulus

Fig.5. The side core pulling mechanism

Fig.6. The temperature control system of mold

Fig.7. 3D schematic diagram of mold temperature control system

Fig.8. Exhaust system of the injection mould

Fig.9. The injection mold stracture of car rearview mirror substrates

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