[0001] The present disclosure is generally related to an assembly for molding a preform, and more particularly related to a cavity 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 used for making hollow shape articles by using a 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 cavity insert assembly 100 for molding a preform. The cavity insert assembly 100 comprises a single piece cavity insert 102, a core insert 104, a sleeve 106, and a lip cavity 108. The single piece cavity insert 102 comprises of an inner molding surface for allowing the core insert 104 to be positioned inside the single piece cavity

insert 102. During operation, a base of the single piece cavity insert 102 wears out upon rubbing with the lip cavity 108. In such case, the single piece cavity insert 102 needed to be replaced by a new cavity insert, after certain intervals, and this led to increased operational cost of the system.
[0005] 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
[0006] 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.
[0007] Figure 1 illustrates a cross sectional view of a cavity insert assembly 100 for molding a preform, according to prior art.
[0008] Figure 2A illustrates a cross sectional view of a stack 200 of an injection molding system comprising a 2-piece steel construction of a cavity insert assembly used in blow molding for manufacturing a preform, according to an embodiment.

[0009] Figures 2B and 2C illustrate a cross sectional view of a cavity insert 202 and a lock ring 206 of the cavity insert assembly of Figure 2A, according to an embodiment.
[0010] Figure 3A illustrates a cross sectional view of a stack 300 of an injection molding system comprising a 3-piece steel/ aluminium construction of a cavity insert assembly used in blow molding for manufacturing a preform, according to an embodiment.
[0011] Figures 3B, 3C, and 3D illustrate a cross sectional view of a gate 304, a cavity insert 302, and, a lock ring 308 respectively of a cavity insert assembly, according to an embodiment.

DETAILED DESCRIPTION
[0012] 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.
[0013] 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.
[0014] 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.
[0015] 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.

[0016] In the description that follows, terms such as "top/upper," "mid," "bottom", "right," "left," "back," "front," "horizontal," "vertical," "forward," and "rear" used with respect to system components in the drawings should not be understood to necessarily connote a particular orientation of the components during use.
[0017] Figure 2A illustrates a cross-sectional view of a stack 200 of an injection molding system comprising a cavity insert assembly. The cavity insert assembly comprises a cavity insert 202. The cavity insert 202 may be retained in a cavity plate 204 through a lock ring 206. In one case, the lock ring 206 may be connected to the cavity plate 204 using screws (not shown). The lock ring 206 is further illustrated in Figure 2C. Further, cooling channels 208, 210, and 212 may circulate cooling fluid from a source (not shown) through the cavity insert 202, to remove heat carried by a molten material. The cross-sectional view of the stack 200 further illustrates a core insert 214 fitted into a core plate 216. In one case, the core insert 214 may comprise of an upper portion, an upper mid-section, a lower mid-section, and a lower portion.
[0018] Further, the core insert 214 may be fitted into the core plate 216. In one case, the core insert 214 may be fitted into the core plate 216 using screws 218. The core insert 214 may contain a cooling tube 220 for transmission of cooling fluid from a source (not shown) within the core insert 214. The cooling fluid may be transmitted to remove heat of a molten material present in a mold cavity 222. The cooling fluid may cool and solidify a molded part i.e. a preform formed over the core insert 214. In one case, the molten material or molten plastic may be fed through a hot runner nozzle 224 to the mold cavity 222. In one case, a hot runner manifold 226, mounted on a manifold plate 228, may comprise of several hot runner nozzles operating similar to the hot runner nozzle 224.
[0019] Further, the cross sectional view of the stack 200 illustrates a lip cavity 230 joined with the lock ring 206. In one case, the lip cavity 230 may be joined with the lock ring 206 using

screws (not shown). The lip cavity 230 may comprise of an upper portion and a lower portion. In one case, the upper portion of the lip cavity 230 may comprise a mold for forming threads on a topmost section of the preform.
[0020] In one embodiment, a ring 232 may be placed at the lower mid-section of the core insert 214. Further, the ring 232 may comprise of an upper portion and a bottom portion. In one case, the upper portion of the ring 232 may comprise of an area forming a gap with the upper mid-section of the core insert 214. In one case, a circular protrusion of the lip cavity 230 may fit into the gap formed by the ring 232. Further, the bottom portion of the ring 232 may comprise of threads for locking with the lower mid-section of the core insert 214.
[0021] In one embodiment, the cavity insert assembly may be manufactured as 2-pieces, as illustrated in Figure 2B and Figure 2C. The 2-pieces may be fabricated separately or using a single die. If manufactured separately, the 2-pieces may be prepared using different materials.
[0022] Advantageously, the cavity insert 202 and the core insert 214 may be manufactured using a pre-hardened steel of grade 1.2316. In one case, the cavity insert 202 may be made of aluminium for having better conductivity. The lock ring 208 and the ring 232 may be manufactured using one of the pre-hardened steel of grade 1.2316 and a full hardened steel of grade 1.2344 (H-13), 1.2343 (H-11), 1.2083, EN 31, or EN 24. Advantageously, for being made using the pre-hardened steel or the full hardened steel, the lock ring 208 and the ring 232 may be more resistant to wear and tear. Further, the lock ring 206 and the ring 232 are simpler components to manufacture relative to the cavity insert 202 and the core insert 214, and thus the lock ring 308 and the ring 334 could be easily replaced upon being damaged. Thus, making the cavity insert assembly less expensive and economically significant.

[0023] Figure 3A illustrates a cross-sectional view of a stack 300 of an injection molding system comprising a cavity insert assembly. The cavity insert assembly comprises a cavity insert 302 and a gate insert 304. In one case, the cavity insert 302 and the gate insert 304 may comprise of two separate pieces as shown in Figure 3B and Figure 3C respectively. The cavity insert 302 and the gate insert 304 may be retained in a cavity plate 306 through a lock ring 308. In one case, the lock ring 308 may be connected to the cavity plate 306 using screws (not shown). Further, cooling channels 310, 312 and 314 may circulate cooling fluid from a source (not shown) through the cavity insert 302 and the gate insert 304 to remove heat from the molten plastic.
[0024] Further, the core insert 316 may be fitted into a core plate 318. In one case, the core insert 316 may be fitted into the core plate 318 using screws 320. Further, the core insert 316 may comprise of an upper portion, a mid section and a lower portion. The core insert 316 may contain a cooling tube 322 for transmission of cooling fluid from a source (not shown) within the core insert 316. The cooling fluid may be transmitted to remove heat from a molten material present in a mold cavity 324. The cooling fluid may cool and solidify a molded part i.e. a preform formed over the core insert 316. The molten material or molten plastic may be fed through a hot runner nozzle 326 to the mold cavity 324. In one case, a hot runner manifold 328, mounted on a manifold plate 330, may comprise of several hot runner nozzles operating similar to the hot runner nozzle 326.
[0025] Further, the cross sectional view of the stack 300 illustrates a lip cavity 332 joined with the lock ring 308. In one case, the lip cavity 332 may be joined with the lock ring 308 using screws (not shown). The lip cavity 332 may comprise of an upper portion and a lower portion. In one case, the upper portion of the lip cavity 332 may comprise a mold for forming threads on a topmost section of the preform.

[0026] In one embodiment, a ring 334 may be placed at the lower mid-section of the core insert 316. Further, the ring 334 may comprise of an upper portion and a bottom portion. In one case, the upper portion of the ring 334 may comprise of an area forming a gap with the upper mid-section of the core insert 316. In one case, a circular protrusion of the lip cavity 332 may fit into the gap formed by the ring 334. Further, the bottom portion of the ring 334 may comprise of threads for locking with a lower mid-section of the core insert 316.
[0027] In one embodiment, the cavity insert assembly may be manufactured into 3-pieces, as illustrated in Figure 3B, Figure 3C, and Figure 3D. The 3-pieces may be fabricated separately or using a single die. If manufactured separately, the 3-pieces may be prepared using different materials.
[0028] Advantageously, the cavity insert 302 and the core insert 316 may be manufactured using a pre-hardened steel of grade 1.2316. In one case, the cavity insert 302 may be made of aluminium for having better conductivity. The lock ring 308 and the ring 334 may be manufactured using one of the pre-hardened steel of grade 1.2316 and a full hardened steel of grade 1.2344 (H-13), 1.2343 (H-11), 1.2083, EN 31, or EN 24. Advantageously, for being made using the pre-hardened steel or the full hardened steel, the lock ring 308 and the ring 334 may be more resistant to wear and tear. Further, the lock ring 308 and the ring 334 are simpler components to manufacture relative to the cavity insert 302 and the core insert 316, and thus the lock ring 308 and the ring 334 could be easily replaced upon being damaged. Thus, making the cavity insert assembly less expensive and economically significant.
[0029] The cavity insert assembly as explained above may be used for manufacturing Polyethylene Terephthalate (PET) bottles. Further, the PET bottles may have neck sizes of up to 120 mm. In some cases, PET bottles with neck sizes of up to 38 mm may only be prepared using the cavity insert assembly.

[0030] Description of the embodiments of the present inventions 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.
[0031] 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 cavity insert assembly used for molding a preform, the cavity insert assembly
comprising:
a cavity insert (202, 302) comprising an inner molding surface for allowing a core insert (214, 316) to be positioned inside the cavity insert (202, 302) to shape the preform, wherein the cavity insert (202, 302) is made of a pre-hardened steel; and
a lock ring (206, 308) connected at an end of the cavity insert (202, 302) facing the core insert (214, 316) for shaping the preform over the core insert (214, 316), wherein the lock ring (206, 308) is made using one of the pre-hardened steel and a full hardened steel.
2. The cavity insert assembly of claim 1, wherein the cavity insert assembly is used for manufacturing Polyethylene Terephthalate (PET) bottles.
3. The cavity insert assembly of claim 2, wherein neck sizes of the PET bottles ranges up to 120 mm.
4. The cavity insert assembly of claim 1, wherein the cavity insert (202, 302) and the lock ring (206, 308) are manufactured separately.
5. The core insert assembly of claim 1, wherein the core insert assembly is fabricated as a 2-piece construction comprising the cavity insert (202) and the lock ring (206).

6. The core insert assembly of claim 5, wherein the 2-piece construction is manufactured using steel.
7. The core insert assembly of claim 1, wherein the core insert assembly is fabricated as a 3-piece construction comprising the cavity insert (302), a gate insert (304), and the lock ring (308).
8. The core insert assembly of claim 1, wherein the 3-piece construction is manufactured using steel or aluminium.
9. The core insert assembly of claim 1, wherein the pre-hardened steel is of grade 1.2316 and the full hardened steel is of grade 1.2344 (H-13), 1.2343 (H-11), 1.2083, EN31, or EN 24.
10. The core insert assembly of claim 1, wherein the cavity insert (202, 302) is made of aluminium.