Molten plastic is shot into the mold, and held for a short time to cool. This results in additional cost and added processing problems. The segments of a collapsible core are attached to the ejector plate, while its tapered inner center pin is attached to the back of the mold.
Angular pin usually fixes by cavity plate and slide locking block.5. The slider stroke …

Sequence of operating the slide core unit for two-color injection mold Primary molding ①Mold opening condition ②Mold closing (the slide core is advanced by the primary side angular cam, causing the slide core to lock), and molding of the first color ③Mold opening while the primary molded product (undercut part) is supported Secondary molding

Close alignment of the core is accomplished through tight tolerance entrance and exit holes in the core plate.

Angular pin: This pin has draft angle from 10 deg ~25 deg. Figure courtesy of Takao Injection Mold Engineering Co., Ltd., 2004. It will transfer vertical movement of cavity plate to horizontal movement of slide core. The sliding surface cooperates with the hole wall of the inclined top swing rod.


Solving this numerically, a universal graph is produced to help engineers predict core deflection. Here, the mold halves are split horizontally along the long axis of the part. There are different methods of actuating a sliding core.

Usually, the diameter of the main runner needs to be big enough, so that the sprues are not completely solidified when injection molding.

All core sliders adopt the press plate + guide pin + spring structure as shown in the diagram (sometimes, when the slider is wider than 100 and yet it is not convenient to adopt the structure, T-plate structure may be considered).

Core bending often complicates the injection molding of thin slender parts. 2. "Galling" is the abnormal wear of sliding surfaces, and the causes of abnormal wear are classified as follows.

When the mold opens, the threaded outer core collapses as the ejector plate moves forward. A slide core mold for injection molding according to the present invention employs, in place of the conventional fitting sliding between an inclined pin and an inclined hole which requires a high precision, an inclined-surface sliding which is simple in construction, whereby the sliding is propelled by the joined pressing force thereof. How to ensure enough slider stroke to facilitate ejection of plastic parts?

In order to increase the hardness of the sliding surface, the part should be made of high hardness inserts. As the mold for plastic injection molding is continued to be used, the slide core or ejector pin, ejector sleeve, and center pin, etc., can cause what is called "galling".

Abrasive wear.

No.1. Heel blocks (wedges) are normally used behind the sliding core to withstand injection pressure acting on the sliding core. Injection moulding is a formative manufacturing technology, i.e. Mold adhesion, also known as sticking sprues or parts, is caused by improper contact of the nozzle tip with the sprue bushing, which does not allow sprue or part release and good filling. material is formed from an amorphous shape into a fixed shape defined by a mould tool.

The guide block acts as an angle pin when the mold opens, and as a locking block during …


Here, a fifth order nonlinear ordinary differential equation is derived for core deflection caused by a Newtonian liquid race tracking through the slit between the core and the rigid cavity wall. In the side core pulling mechanism of the cam link bar. It will increase strength for the angular pin when mold closed.4. The most common of these use horn or angle pins (see Figure 1) to move the slide when the mold opens or closes.

Slide locking block: It uses to assemble an angular pin and cavity plate. To reduce the wear of the sliding surface, the actual mating surface should not be too long. When the molding cycle begins, the mold closes and the side action slides on an angled pin at the same rate so they are seated shut at the exact same time.

Two pictures below will explain construction of slide core system.1. Mold Adhesion (sticking) in Injection Molding Process. Cavity plate.3.

Almost every plastic part created today is by injection moulding as it allows identical parts to be created in huge numbers, in a short space of time, and at very low cost per part.