[0001] The present disclosure is generally related to an assembly for molding a preform, and more particularly related to a core insert assembly.
BACKGROUND
[0002] The subject matter discussed in the background section should not be assumed to be prior art merely as a result of its mention in the background section. Similarly, a problem mentioned in the background section or associated with the subject matter of the background section should not be assumed to have been previously recognized in the prior art. The subject matter in the background section merely represents different approaches, which in and of themselves may also correspond to implementations of the claimed technology.
[0003] Blow molding is a manufacturing process for making hollow shape articles by using a molten material, generally plastic. The process requires the material to be molded into a preform positioned onto a core insert. The material is injected through a hot runner manifold, into a space present between a cavity insert and the core insert. The preform is further heated at a specific temperature and blown into the hollow shape articles.
[0004] Figure 1 illustrates a cross sectional view of a core insert assembly 100 for molding a preform. The core insert assembly 100 comprises a cavity insert 102, a core insert 104, a sleeve 106, and a lip cavity 108. The core insert 104 is positioned within the sleeve 106. During operation, the lip cavity 108 connected with the sleeve 106 rubs with the sleeve 106, thereby

damaging the core insert assembly 100. Thus, wear and tear of the sleeve 106 resulted into the necessity of changing an entire assembly comprising the core insert 104 and the sleeve 106, and this led to increased operational cost of the system.
[0005] Figure 2 illustrates a cross sectional view of a core insert assembly 200 used for molding a preform. The core insert assembly comprises of a cavity insert 202, a single piece core insert 204, and a lip cavity 206. The cavity insert 202 comprises of an inner molding surface for allowing the single piece core insert 204 to be positioned inside the cavity insert 202. During operation, a head or an upper section of the single piece core insert 204 wears out upon repeated engagement and disengagement with the lip cavity 206. In such case, the single piece core insert 204 is needed to be replaced after a defined usage, resulting into a higher operational cost of the system.
[0006] Conventionally use core inserts, as described above using Figure 1 and Figure 2, are installed into a mold from behind. To replace a damaged core insert, a bottom plate of the mold is required to be separated from other components required to hold the damaged core insert in place. This brings the entire operation to a halt and results in manufacturing downtime.
[0007] Thus, an efficient assembly for molding of preforms that could reduce operational cost and improve efficiency of operation is much desired.
BRIEF DESCRIPTION OF THE DRAWINGS
[0008] The accompanying drawings illustrate various embodiments of systems, methods, and embodiments of various other aspects of the disclosure. Any person with ordinary skills in the art will appreciate that the illustrated element boundaries (e.g. boxes, groups of boxes, or other shapes) in the figures represent one example of the boundaries. It may be that in some examples

one element may be designed as multiple elements or that multiple elements may be designed as one element. In some examples, an element shown as an internal component of one element may be implemented as an external component in another, and vice versa. Furthermore, elements may not be drawn to scale. Non-limiting and non-exhaustive descriptions are described with reference to the following drawings. The components in the figures are not necessarily to scale, emphasis instead being placed upon illustrating principles.
[0009] Figure 1 illustrates a cross sectional view of a core insert assembly 100 used for molding a preform, according to prior art.
[0010] Figure 2 illustrates a cross sectional view of a core insert assembly 200 used for molding a preform, according to prior art.
[0011] Figure 3A illustrates a cross sectional view of a stack 300 of an injection molding system comprising a core insert assembly used in blow molding for manufacturing a preform, according to an embodiment.
[0012] Figures 3B, 3C, and 3D illustrate a cross sectional view of a core insert 302, a ring 334, and a lip cavity 332 respectively of the stack 300 of the injection molding system, according to an embodiment.

DETAILED DESCRIPTION
[0013] Some embodiments of this disclosure, illustrating all its features, will now be discussed in detail. The words "comprising," "having," "containing," and "including," and other forms thereof, are intended to be equivalent in meaning and be open ended in that an item or items following any one of these words is not meant to be an exhaustive listing of such item or items, or meant to be limited to only the listed item or items.
[0014] It must also be noted that as used herein and in the appended claims, the singular forms "a," "an," and "the" include plural references unless the context clearly dictates otherwise. Although any systems and methods similar or equivalent to those described herein can be used in the practice or testing of embodiments of the present disclosure, the preferred, systems and methods are now described.
[0015] Embodiments of the present disclosure will be described more fully hereinafter with reference to the accompanying drawings in which like numerals represent like elements throughout the several figures, and in which example embodiments are shown. Embodiments of the claims may, however, be embodied in many different forms and should not be construed as limited to the embodiments set forth herein. The examples set forth herein are non-limiting examples and are merely examples among other possible examples.
[0016] In the detailed description that follows, numerous specific details are set forth in order to provide a thorough understanding of several non-limiting embodiments of a core insert assembly. However, it will be recognized by one of ordinary skill in the art that the core insert assembly may be practiced without these specific details. In other instances, well known methods, procedures, and components have not been described in detail as not to unnecessarily obscure aspects of the present invention.

[0017] In the description that follows, terms such as "top/upper," "mid", "bottom/lower", “back," and "front" used with respect to system components in the drawings should not be understood to necessarily connote a particular orientation of the components during use.
[0018] Figure 3A illustrates a cross-sectional view of a stack 300 of an injection molding system comprising a core insert assembly used in blow molding for manufacturing a preform. The core insert assembly may comprise a core insert 302. The core insert 302 may be fitted into a core plate 304. In one case, the core insert 302 may be fitted using screws 306. The core insert 302 may comprise of an upper portion 302a, a mid-section 302b, and a lower portion 302c, as shown in Figure 3B.
[0019] Further, the core insert 302 may contain a cooling tube 308 for transmission of a cooling fluid, generally water, from a source (not shown) within the core insert 302. In one case, the cooling tube 308 may be present in a center of the core insert 302. The cooling fluid may be transmitted to remove heat of a molten plastic flowing in a mold cavity 310. The cooling fluid may cool and solidify a molded part i.e. a preform formed over the core insert 302. The molten plastic or molten material may be fed through a hot runner nozzle 312 to the mold cavity 310. In one case, a hot runner manifold 314, mounted on a manifold plate 316, may comprise several hot runner nozzles operating similar to the hot runner nozzle 312.
[0020] Further, the cross sectional view of the stack 300 illustrates a cavity insert 318 and a gate insert 320. The cavity insert 318 and the gate insert 320 may be retained in a cavity plate 322 using a lock ring 324. In one case, the lock ring 324 may be joined to the cavity plate 322 using screws (not shown). In one case, the cavity insert 318 and the gate insert 320 may be present as a single piece. Further, cooling channels 326, 328, and 330 may circulate cooling fluid from a source (not shown) through the cavity insert 318 and gate insert 320 to remove heat carried by the molten plastic.

[0021] Further, the cross sectional view of the stack 300 illustrates a lip cavity 332 joined with the lock ring 324. In one case, the lip cavity 332 and the lock ring 324 may be joined using screws (not shown). Further, a ring 334 may be attached to the mid-section 302b of the core insert 302. The ring 334 may comprise of an upper portion 334a and a bottom portion 334b, as illustrated in Figure 3C. In one case, the upper portion 334a of the ring 334 may form a gap with the upper portion 302a of the core insert 302. In one case, a circular protrusion 336 of the lip cavity 332 may fit into the gap formed by the ring 334, as illustrated in Figure 3D. Further, the bottom portion 334b of the ring 334 may comprise of threads for locking with threads present on the mid-section 302b of the core insert 302.
[0022] Advantageously, the core insert 302 and the cavity insert 318 may be manufactured using a pre-hardened steel of grade 1.2316. Likewise, the lock ring 324 and the ring 334 may be manufactured using a full hardened steel of grade 1.2344 (H-13), 1.2343 (H-11), 1.2083, EN 31, or EN 24. Advantageously, due to a difference in pre-hardening and hardening values, the lock ring 324 and the ring 334 may wear faster than the core insert 302 and the cavity insert 318. Whereby, the lock ring 324 and the ring 334 being simpler components to manufacture relative to the core insert 324 and the cavity insert 318, and thus less expensive, may be more economically replaced.
[0023] The core insert assembly describes above may be used for manufacturing Polyethylene Terephthalate (PET) bottles. Further, PET bottles with neck sizes of up to 120 mm may be prepared using the core insert assembly. In some cases, PET bottles with neck sizes of up to 38 mm may only be prepared using the core insert assembly.
[0024] Thus, core inserts fitted into core plates using screws provide the advantage of unscrewing a damaged core insert quickly from front side of the core plates, without requiring dissociating all the parts holding the core inserts.

[0025] Description of the embodiments of the present invention provides examples of the present invention, and these examples do not limit the scope of the present invention. It is to be expressly understood that the scope of the present invention is limited by the claims. The concepts described above may be adapted for specific conditions and/or functions, and may be further extended to a variety of other applications that are within the scope of the present invention. Having thus described the embodiments of the present invention, it will be apparent that modifications and enhancements are possible without departing from the concepts as described.
[0026] It is noted that the foregoing has outlined some of the more pertinent non-limiting embodiments of the present invention. This invention may be used for many applications. Thus, although the description is made for particular arrangements and methods, the intent and concept of the invention is suitable and applicable to other arrangements and applications. It will be clear to those skilled in the art that modifications to the disclosed embodiments can be effected without departing from the spirit and scope of the invention. The described embodiments ought to be construed to be merely illustrative of some of the more prominent features and applications of the invention. Other beneficial results can be realized by applying the disclosed invention in a different manner or modifying the invention in ways known to those familiar with the art. This includes the mixing and matching of features, elements and/or functions between various embodiments is expressly contemplated herein so that one of ordinary skill in the art would appreciate from this disclosure that features, elements and/or functions of one embodiment may be incorporated into another embodiment as skill in the art would appreciate from this disclosure that features, elements and/or functions of one embodiment may be incorporated into another embodiment as appropriate, unless described otherwise, above.

CLAIMS

A core insert assembly used for molding a preform, the core insert assembly comprising:
a core insert (302) comprising an upper portion (302a), a mid-section (302b), and a lower
portion (302c), wherein the upper portion (302a) is fabricated for allowing a cavity insert (318) to be inserted onto the core insert (302); and
a ring (334) comprising of an upper portion (334a) and a bottom portion (334b), wherein at least an area of the upper portion (334a) of the ring (334) forms a gap with the upper portion (302a) of the core insert (302), for positioning a circular protrusion (336) of a lip cavity (332) in the gap, and the bottom portion (334b) of the ring (334) comprises threads for locking with threads present on the mid-section (302b) of the core insert (302).
2. The core insert assembly of claim 1, wherein the upper portion (302a), the mid-section (302b), and the lower portion (302c) of the core insert are manufactured at a same time.
3. The core insert assembly of claim 1, further comprising a lock ring (324) positioned between the lip cavity (332) and the cavity insert (318).
4. The core insert assembly of claim 1, wherein the ring (334) is attached to the mid-section (302b) of the core insert (302) using screws.
5. The core insert assembly of claim 1, wherein the core insert (302) is manufactured using pre-hardened steel of grade 1.2316.

6. The core insert assembly of claim 1, wherein the ring (334) is manufactured using full hardened steel of grade 1.2344 (H-13), 1.2343 (H-ll), 1.2083, EN 31, or EN 24.
7. The core insert assembly of claim 1, wherein the core insert assembly is used for manufacturing Polyethylene Terephthalate (PET) bottles.
8. The core insert assembly of claim 7, wherein neck sizes of the PET bottles ranges up to 120 mm.
9. The core insert assembly of claim 1, further comprising fitting the core insert (302) into a core plate (304) using screws (306).