be explored．
In theory,numerical simulation offers all access to learn
about shrinkage displacements of points oll an injection
molded plastic part． But aiming at acceptable
computational cost，so far commercial simulation softwares
for injection molding process only consider the constraint
of a prominent part insert on the plastic part’s shrinkage，
not considering the constraint of the cavity on the plastic
part’s shrinkage．In fact，the inymold shrinkage constraint is
a main cause for nonuniform shrinkage ratios．
In this study,we fabricated a visualization mold to get
photos containing both the part’s profile and the cavity’s
profile．After digital image processing of the in—moldshrinkage photos，experimental data concerning shrinkage
directions and shrinkage distances were discussed．
2 Design of the Visualization Mold
Visualization method has been widely used for observing
flow of plastic melt in the cavity of an injection mold．
OZDEMIR．et all，J．videoed flOW front advancement of
thermoplastic melt in a cavity owning conventional
dimensions．YANG，et al例．videoed flow behavior of core
material during sandwich injection molding．And the filling
behavior during micro．iIliection molding Can alSO be
visualizedl9-10】．Usually one quartz glass window is inserted
in the visual mold，and the cavity is brightened and
observed by l培ht reflection either through a prism quartz
glass or through a mirror．As for observing in．mold
shrinkage，FATⅢ，et a1L“J，videoed the separation course of
the plastic part surface from the glass surface also by light
reflection manner．The stllJcture of the viSual mold used bv
FArHI，et al【“j is shown in Fig．1．but they did not自reat of
shape contrast between the part and the cavity．Because
profiles of the part and of the cavity Can not be
distinguished clearly by light reflection manner,we
adopted light transmission nlanner for observing the shape
contrast between the part and the cavity．n圮light
transmission manner demands that both the upper surface
and the under吼Ⅱface of the cavity are made of quartz glass
blocks．Comparing with the visual mold owning single
quartz glass block, an injection mold owning two
face．．to．．face quartz glass blocks has the advantage in
balance of flowing condition and thermal condition for the
plastic melt．But use of two quartz glass blocks raises
difficulty for design of the visual mold．For purpose of
obtaining profiles of both the part and the cavity,the two
quartz glass windows need to be larger than the cavity in
length and width．In addition．planar dimensions of the
cavity are expected to be Iarge SO as to increase shrinkage
distances of points on the part．So if the parting direction is
parallel to也e opening direction ofthe injection machine as
normal，the stationary side of the mold requires either a
bulky prism quartz glass block which iS rather difficult to
fabricate or a large mirror which means a huge hollow of
the mold and then a great decrease on the mold stiffness．Wb found out a way to avoid above—mentioned
disadvantage by using the half mold sucn．As shown in
Fig．2 and Fig．3，when the parting direction is
perpendicular to the opening direction of theection
machine，both observation and light introduction are
facilitated．Opening and closing of the half molds are
controlled by the inclined guide pins，and the clamping
force is offered by the locking blocks and reinforced by the
relocking blocks．文摘:在收缩的现有研究注塑塑料零件主要集中在各种收缩比率的部分，尺寸和相关实验研究属于纯粹的尺寸测量后脱模。显然,测量后的塑料部分是脱模后从腔叫不提供收缩位移点塑料零件。然而,收缩位移点注射成型塑料零件的暴露内部关系收缩比率的各种规格的部分，所以可视化在模具塑料零件可以指出位置关系和腔需要部分。在本文中,一个视觉注塑模具为基体,采用半模结构及光传输方式。与视觉模具,在模具收缩图像注塑塑料零件被拍到在塑料注塑模具的部分留在24 h。通过数字图像处理在模具收缩图像,实验数据点的收缩位移对注塑件进行了研究。从实验数据,结果表明,收缩方向的点在所有注塑相关部分与两种立场是门和中美部分重心, 要么门口或重心将发挥更大的影响在收缩方向的一些点较近。此外,一些点在以后有更多的收缩距离覆盖的地区比点覆盖的地区越早。结合收缩方向和收缩的距离点注射模制品收缩比率确定各种文度的部分,和收缩的方向更有影响力的收缩比率的文度。本实验研究提供了一个独特的收缩位移分析方法,了解了注塑件收缩原则 注塑模的收缩位移点英文文献和翻译(2):http://www.youerw.com/fanyi/lunwen_5151.html