Molded article having selectively variable core geometry and hot runner nozzle for making the same
阅读说明:本技术 具有选择性变化的芯层几何形状的模制品以及用于制造该模制品的热流道喷嘴 (Molded article having selectively variable core geometry and hot runner nozzle for making the same ) 是由 让-克里斯托夫·维茨 克里斯托夫·西蒙·皮埃尔·贝克 乔基姆·约翰尼斯·尼韦尔斯 李·理查德· 于 2018-06-21 设计创作,主要内容包括:一种适于随后吹塑成最终成形容器的模制品。该模制品包括颈部;浇口部;以及主体部,主体部在颈部和浇口部之间延伸,主体部的至少大部分具有关于纵向延伸穿过主体部的中心的主体轴线对称的整体形状。主体部包括:第一聚合材料的内部外层和外部外层;以及第二聚合材料的芯层,第二聚合材料的芯层设置在内部外层和外部外层之间。芯层的径向厚度或材料选择性地改变以控制模制品到最终成形容器中的不均匀吹塑。(A molded article suitable for subsequent blow molding into a final shaped container. The molded article includes a neck portion; a gate portion; and a body portion extending between the neck portion and the gate portion, at least a majority of the body portion having an overall shape that is symmetrical about a body axis extending longitudinally through a center of the body portion. The main body part includes: an inner outer layer and an outer layer of a first polymeric material; and a core layer of a second polymeric material disposed between the inner outer layer and the outer layer. The radial thickness or material of the core layer is selectively varied to control uneven blow molding of the molded article into the final shaped container.)
1. A molded article suitable for subsequent blow molding into a final shaped container, said molded article comprising:
a neck portion;
a gate portion; and
a body portion extending between the neck portion and the gate portion, at least a majority of the body portion having an overall shape that is symmetrical about a body axis extending longitudinally through a center of the body portion, at least the body portion comprising:
an inner outer layer and an outer layer of a first polymeric material; and
a core layer of a second polymeric material disposed between at least a portion of the inner and outer layers, the core layer having a radial thickness that is selectively varied to control non-uniform blow molding of the molded article into the final shaped container.
2. The molded article of claim 1, wherein:
the thermal crystallization rate of the first polymeric material is substantially less than the thermal crystallization rate of the second polymeric material; and is
The first polymeric material includes at least one of a strain crystallizable homopolymer, copolymer, and blend of polyethylene terephthalate (PET).
3. The molded article of claim 2, wherein at least a majority of the neck portion is comprised of the first polymeric material and is free of the second polymeric material.
4. The molded article of claim 1, wherein the second polymeric material has a substantially higher intrinsic viscosity than the first polymeric material.
5. The molded article of any of claims 1-4, wherein a radial thickness of the core layer varies about the body axis.
6. The molded article of claim 5, wherein the radial thickness of the core layer has an asymmetric annular form about the body axis.
7. The molded article of claim 5, wherein the radial thickness of the core layer has a symmetrical annular form about the body axis.
8. The molded article of claim 5, wherein the core layer has a semi-annular core layer.
9. The molded article of any of claims 1-8, wherein a radial thickness of the core layer varies in an axial direction.
10. The molded article of any of claims 1-9, wherein the core layer is interrupted such that:
the radial thickness of the core layer decreases to zero at least one location; and is
The inner outer layer and the outer layer are in contact at the at least one location.
11. The molded article of any of claims 1-10, further comprising:
a transition portion extending between the neck portion and the body portion; and wherein:
the transition portion comprises a transition inner layer and a transition outer layer of a first polymeric material; and
a transitional core layer of a second polymeric material disposed between at least a portion of the inner outer layer and the outer layer.
12. The molded article of claim 11, wherein the transitional core layer is interrupted such that the radial thickness of the transitional core layer decreases to zero at least one location.
13. The molded article of claim 1, wherein the core layer has a localized region of increased radial thickness.
14. A molded article suitable for subsequent blow molding into a final shaped container, said molded article comprising:
a neck portion;
a gate portion; and
a body portion extending between the neck portion and the gate portion, at least the body portion comprising:
an inner outer layer and an outer layer of a first polymeric material; and
a core layer of a second polymeric material disposed between at least a portion of the inner outer layer and the outer layer,
the first polymeric material has a thermal crystallization rate that is substantially less than a thermal crystallization rate of the second polymeric material,
the second polymeric material includes at least one of a strain crystallizable homopolymer, copolymer, and blend of polyethylene terephthalate (PET).
15. A molded article suitable for subsequent blow molding into a final shaped container, said molded article comprising:
a neck portion;
a gate portion; and
a body portion extending between the neck portion and the gate portion, at least the body portion comprising:
an inner outer layer and an outer layer of a first polymeric material; and
a core layer of a second polymeric material disposed between at least a portion of the inner outer layer and the outer layer,
the second polymeric material has a substantially higher intrinsic viscosity than the first polymeric material.
16. A molded article suitable for subsequent blow molding into a final shaped container, said molded article comprising:
a neck portion;
a gate portion; and
a body portion extending between the neck portion and the gate portion, at least a majority of the body portion having an overall shape that is symmetrical about a body axis extending longitudinally through a center of the body portion, at least the body portion comprising:
an inner outer layer and an outer layer of a first polymeric material; and
a core layer of a second polymeric material disposed between at least a portion of the inner outer layer and the outer layer, the core layer having a radial thickness that selectively varies to produce a change in color distribution in the final shaped vessel.
17. The molded article of claim 16, wherein:
the first polymeric material has a first color; and is
The second polymeric material has a second color different from the first color.
18. The molded article of claim 16 or 17, wherein the radial thickness of the core layer varies about the body axis.
19. The molded article of any of claims 16-18, wherein the radial thickness of the core layer has an asymmetric annular form about the body axis.
20. The molded article of any of claims 16-19, wherein the core layer has a localized region of increased radial thickness.
21. A hot runner nozzle for delivering melt to a mold cavity, the hot runner nozzle comprising:
an inner nozzle insert defining an inner flow passage;
a middle nozzle insert disposed around the inner nozzle insert,
the intermediate nozzle insert and the inner nozzle insert defining an intermediate flow channel; and
an outer nozzle insert disposed around the middle nozzle insert, the outer nozzle insert and the middle nozzle insert defining an outer flow passage,
the intermediate nozzle insert and the inner nozzle insert cooperate to define an intermediate outlet,
at least one of the inner nozzle insert and the intermediate nozzle insert further defines at least one orifice disposed upstream of the intermediate outlet, the at least one orifice being arranged in fluid connection with at least one of the inner flow channel and the outer flow channel.
22. The hot runner nozzle according to claim 21, wherein, in use, when delivering the melt to the mold cavity:
a first melt stream of a first polymeric material flows through and exits the inner flow channel and the outer flow channel;
a second melt stream of a second polymeric material flows through the intermediate flow channel; and
at least a portion of the second melt stream passes from the intermediate flow channel through the at least one orifice to at least one of the inner flow channel and the outer flow channel.
23. The hot runner nozzle according to claim 22, wherein:
the intermediate nozzle insert defining the at least one orifice; and is
When in use, at least a portion of the second melt stream passes from the intermediate flow channel through the at least one orifice to the outer flow channel.
24. The hot runner nozzle according to claim 23, wherein the at least one orifice comprises:
a first plurality of apertures defined along a first line extending longitudinally along the intermediate nozzle insert; and
a second plurality of orifices defined along a second line extending longitudinally along the intermediate nozzle insert, the first line and the second line being separate from one another.
25. The hot runner nozzle according to claim 22, wherein:
the inner nozzle insert defining the at least one orifice; and is
When in use, at least a portion of the second melt stream passes from the intermediate flow channel through the at least one orifice to the inner flow channel.
26. The hot runner nozzle according to claim 25, wherein the at least one orifice comprises:
a first plurality of apertures defined along a first line extending longitudinally along the inner nozzle insert; and
a second plurality of orifices defined along a second line extending longitudinally along the inner nozzle insert, the first line and the second line being separate from one another.
27. The hot runner nozzle according to any one of claims 22 to 26 wherein the mold cavity is for defining, in use, a molded article having a core layer and a skin layer surrounding the core layer, the core layer being formed of the second polymeric material flowing through the intermediate flow channel, the core layer having a non-uniform radial thickness about a longitudinal axis of the molded article.
28. The hot runner nozzle according to claim 21, wherein the at least one orifice includes a plurality of orifices fluidly connecting the intermediate flow channel with at least one of the inner flow channel and the outer flow channel.
29. A hot runner nozzle for delivering melt to a mold cavity, the hot runner nozzle comprising:
an inner nozzle insert defining an inner flow passage including an inner outlet;
a middle nozzle insert disposed around the inner nozzle insert,
the intermediate nozzle insert and the inner nozzle insert defining an intermediate flow passage, the intermediate flow passage including an intermediate outlet; and
an outer nozzle insert disposed around the middle nozzle insert,
the outer nozzle insert and the middle nozzle insert defining an outer flow passage, the outer flow passage including an outer outlet,
the inner nozzle insert is formed such that the intermediate outlet has a non-uniform cross-section.
30. The hot runner nozzle according to claim 29, wherein the mold cavity is for defining, in use, a molded article having a core layer and a skin layer surrounding the core layer, the core layer being formed of material flowing through the intermediate flow channel, the material having a non-uniform radial thickness about the axis.
31. The hot runner nozzle according to claim 29, wherein the inner outlet, the intermediate outlet, and the outer outlet are immediately adjacent to one another.
32. The hot runner nozzle according to claim 29, wherein the inner nozzle insert is formed such that the intermediate outlet extends only partially around a longitudinal axis of the hot runner nozzle.
33. The hot runner nozzle according to claim 29, wherein:
the inner nozzle insert having an outer surface partially defining the intermediate flow passage; and
the outer surface has an elliptical form with a center of the elliptical form surface offset from a longitudinal axis of the hot runner nozzle.
34. The hot runner nozzle according to claim 29, wherein the inner outlet and the outer outlet are concentrically arranged.
35. The hot runner nozzle according to claim 34, wherein the intermediate outlet is disposed between a portion of the concentrically arranged inner and outer outlets.
36. The hot runner nozzle according to any one of claims 29 to 35, wherein, in use, when transferring the melt to the mold cavity:
a first melt stream of a first polymeric material flows through and exits the inner flow channel and the outer flow channel;
a second melt stream of a second polymeric material flows through and out of the intermediate flow channel, the second polymeric material forming a core layer of a molded product produced from the melt in the mold cavity; and
the first melt stream and the second melt stream intersect at a junction region.
37. The hot runner nozzle according to any one of claims 29 to 36 wherein the mold cavity is for defining, in use, a molded article having a core layer and a skin layer surrounding the core layer, the core layer being formed of the second polymeric material flowing through the intermediate flow channel, the core layer having a non-uniform radial thickness about a longitudinal axis of the molded article.
38. A hot runner nozzle for delivering melt to a mold cavity, the hot runner nozzle comprising:
an inner nozzle insert defining an inner flow passage;
a middle nozzle insert disposed around the inner nozzle insert,
the intermediate nozzle insert and the inner nozzle insert defining an intermediate flow channel; and
an outer nozzle insert disposed around the middle nozzle insert,
the outer nozzle insert and the middle nozzle insert define an outer flow passage,
when the hot runner nozzle is in use, the flow of material through the intermediate flow passage is non-uniformly distributed about the longitudinal axis of the hot runner nozzle, the non-uniformity of the flow being due to the surfaces of the intermediate nozzle insert and inner nozzle that define the intermediate flow passage,
the mould cavity is for defining, in use, a moulded article having a core layer formed from material flowing through the intermediate flow passage and a skin layer surrounding the core layer, the core layer having a non-uniform radial thickness about a longitudinal axis of the moulded article.
Technical Field
The present technology relates to multilayer molded articles suitable for subsequent blow molding into final shaped containers. More particularly, the present technology relates to molded articles having a core layer that is formed to selectively affect subsequent blow molding properties when the multilayer molded article is processed into a final shaped container.
Background
Molding is a method of forming a molded article from a molding material by using a molding system. Various molded articles can be formed by using a molding process (e.g., an injection molding process). One example of a molded article that can be formed from, for example, polyethylene terephthalate (PET) material is a preform that can be subsequently blown into a beverage container (e.g., a bottle, etc.). In other words, the preform is an intermediate product that is then processed by a stretch blow molding process into a final shaped container (as one example). During stretch blow molding, the material of the preform exhibits certain properties (e.g., stretch ratio, which depends on reheat temperature, etc.).
It will be appreciated that a typical preform is circularly symmetric about its longitudinal axis. Some of the final shaped molded articles are also circularly symmetric. For example, beverage containers (bottles) for still or foamed beverages are substantially symmetrical about their longitudinal axis (e.g., when standing on a shelf). Other final shaped containers are not circularly symmetric. Examples of such non-circularly symmetric final shaped containers include, but are not limited to: containers for household cleaning liquids (e.g., glass cleaning liquids, toilet bowl cleaning liquids, etc.), containers for personal care products (shampoos, conditioners, etc.), and the like.
Blow molding a symmetric preform into an asymmetric container can cause challenges related to the structure and/or stretch blow molding process, such as a weaker wall where the preform has been maximally expanded.
Some preforms (and thus the final shaped containers) are made from a single molding material. For example, the preforms described above for stretch blow molding into beverage containers for still or foamed beverages are typically made from a single material of PET. PET is well suited for these applications. However, PET is not ideally suited for other applications. In this regard, for certain applications, no single material is a viable option (either because it lacks certain properties or because it is not commercially viable). Accordingly, it is also known to make multi-material preforms in which another material (often referred to as a "core material") is added and "sandwiched" between inner and outer layers of one or more other materials.
For example, certain materials may be selected as the core layer to enhance oxygen impermeability (e.g., barrier materials such as EVOH or PGA), enhance light impermeability, and the like.
Disclosure of Invention
The object of the present invention is to ameliorate at least some of the inconveniences of the prior art.
Without wishing to be bound by any particular theory, embodiments of the present technology are developed based on the developer's recognition that the geometry of the core/barrier layer may help to selectively control stretching or blowing of the final shaped container. Developers have also recognized that controlled non-uniform geometry of the core layer can be used for aesthetic purposes, including producing selective color changes in the final shaped container.
In accordance with a first broad aspect of the present technique, there is provided a molded article suitable for subsequent blow molding into a final shaped container. The article comprises a neck portion; a gate portion; and a body portion extending between the neck portion and the gate portion, at least a majority of the body portion having an overall shape that is symmetrical about a body axis extending longitudinally through a center of the body portion, at least the body portion including an inner outer layer and an outer layer of a first polymeric material; and a core layer of a second polymeric material disposed between at least a portion of the inner and outer layers, the core layer having a radial thickness that is selectively varied to control non-uniform blow molding of the molded article into the final shaped container.
In some embodiments of the molded article, the rate of thermal crystallization of the first polymeric material is substantially less than the rate of thermal crystallization of the second polymeric material; and the second polymeric material comprises at least one of a strain crystallizable homopolymer, copolymer, and blend of polyethylene terephthalate (PET).
In some embodiments of the molded article, at least a majority of the neck portion is comprised of the first polymeric material and is free of the second polymeric material.
In some embodiments of the molded article, the second polymeric material has a substantially higher intrinsic viscosity than the first polymeric material.
In some embodiments of the molded article, the radial thickness of the core layer varies about the body axis.
In some embodiments, the core layer has a localized region of increased radial thickness.
In some embodiments of the molded article, the radial thickness of the core layer has an asymmetrical annular form about the body axis.
In some embodiments of the molded article, the radial thickness of the core layer has a symmetrical annular form about the body axis.
In some embodiments of the molded article, the core layer has a semi-annular core layer.
In some embodiments of the molded article, the core layer varies in radial thickness in the axial direction.
In some embodiments of the molded article, the core layer is interrupted such that the radial thickness of the core layer is reduced to zero at least one location; and the inner outer layer and the outer layer are in contact at least one location.
In some embodiments of the molded article, the molded article further comprises a transition portion extending between the neck portion and the body portion; and wherein the transition portion comprises a transition inner layer and a transition outer layer of the first polymeric material; and a transitional core layer of a second polymeric material disposed between at least a portion of the inner outer layer and the outer layer.
In some embodiments of the molded article, the transition core layer is interrupted such that the radial thickness of the transition core layer is reduced to zero at least one location.
In accordance with another broad aspect of the present technique, there is provided a molded article suitable for subsequent blow molding into a final shaped container. The molded article includes a neck portion; a gate portion; and a body portion extending between the neck portion and the gate portion, at least the body portion comprising an inner outer layer and an outer layer of a first polymeric material; and a core layer of a second polymeric material disposed between at least a portion of the inner outer layer and the outer layer, the first polymeric material having a thermal crystallization rate substantially less than a thermal crystallization rate of the second polymeric material, the second polymeric material comprising at least one of a strain crystallizable homopolymer, copolymer, and blend of polyethylene terephthalate (PET).
In accordance with yet another broad aspect of the present technique, there is provided a molded article suitable for subsequent blow molding into a final-shaped container. The molded article includes a neck portion; a gate portion; and a body portion extending between the neck portion and the gate portion, at least the body portion comprising an inner outer layer and an outer layer of a first polymeric material; and a core layer of a second polymeric material disposed between the inner outer layer and at least a portion of the outer layer, the second polymeric material having a substantially higher intrinsic viscosity than the first polymeric material.
In accordance with yet another broad aspect of the present technique, there is provided a molded article suitable for subsequent blow molding into a final-shaped container. The molded article includes a neck portion; a gate portion; and a body portion extending between the neck portion and the gate portion, at least a majority of the body portion having an overall shape that is symmetrical about a body axis extending longitudinally through a center of the body portion, at least the body portion including an inner outer layer and an outer layer of a first polymeric material; and a core layer of a second polymeric material disposed between at least a portion of the inner and outer layers, the core layer having a radial thickness that is selectively varied to produce a change in color distribution in the final shaped vessel.
In some embodiments, the first polymeric material has a first color; and the second polymeric material has a second color different from the first color.
In some embodiments, the radial thickness of the core layer varies about the body axis.
In some embodiments, the radial thickness of the core layer has an asymmetric annular form about the body axis.
In some embodiments, the core layer has a localized region of increased radial thickness.
According to yet another broad aspect of the present technique, there is provided a hot runner nozzle for delivering melt to a mold cavity. The hot runner nozzle includes an inner nozzle insert defining an inner flow passage; an intermediate nozzle insert disposed about the inner nozzle insert, the intermediate nozzle insert and the inner nozzle insert defining an intermediate flow channel; and an outer nozzle insert disposed about the middle nozzle insert, the outer nozzle insert and the middle nozzle insert defining an outer flow channel, the middle nozzle insert and the inner nozzle insert cooperating to define a middle outlet, at least one of the inner nozzle insert and the middle nozzle insert further defining at least one orifice disposed upstream of the middle outlet, the at least one orifice being disposed in fluid connection with at least one of the inner flow channel and the outer flow channel.
In some embodiments, in use, a first melt stream of a first polymeric material flows through and out of the inner and outer flow channels as the melt is delivered to the mold cavity; a second melt stream of a second polymeric material flows through the intermediate flow channel; and at least a portion of the second melt stream passes from the intermediate flow channel through the at least one orifice to at least one of the inner flow channel and the outer flow channel.
In some embodiments, the intermediate nozzle insert defines at least one orifice; and in use, at least a portion of the second melt stream passes from the intermediate flow channel through the at least one orifice to the outer flow channel.
In some embodiments, the at least one orifice comprises a first plurality of orifices defined along a first line extending longitudinally along the intermediate nozzle insert; and a second plurality of orifices defined along a second line extending longitudinally along the intermediate nozzle insert, the first and second lines being separated from one another.
In some embodiments, the inner nozzle insert defines at least one orifice; and in use, at least a portion of the second melt stream passes from the intermediate flow channel through the at least one orifice to the inner flow channel.
In some embodiments, the at least one orifice comprises a first plurality of orifices defined along a first line extending longitudinally along the inner nozzle insert; and a second plurality of orifices defined along a second line extending longitudinally along the inner nozzle insert, the first and second lines being separated from one another.
In some embodiments, the mold cavity is for defining, in use, a molded article having a core layer and a skin layer surrounding the core layer, the core layer being formed of a second polymeric material flowing through the intermediate flow channel, the core layer having a non-uniform radial thickness about a longitudinal axis of the molded article.
In some embodiments, the at least one orifice comprises a plurality of orifices fluidly connecting the intermediate flow channel with at least one of the inner flow channel and the outer flow channel.
According to yet another broad aspect of the present technique, there is provided a hot runner nozzle for delivering melt to a mold cavity. The hot runner nozzle includes: an inner nozzle insert defining an inner flow passage, the inner flow passage including an inner outlet; an intermediate nozzle insert disposed about the inner nozzle insert, the intermediate nozzle insert and the inner nozzle insert defining an intermediate flow passage, the intermediate flow passage including an intermediate outlet; and an outer nozzle insert disposed around the middle nozzle insert, the outer nozzle insert and the middle nozzle insert defining an outer flow channel, the outer flow channel including an outer outlet, the inner nozzle insert being formed such that the middle outlet has a non-uniform cross-section.
In some embodiments, the mould cavity is for defining, in use, a moulded article having a core layer and a skin layer surrounding the core layer, the core layer being formed from material flowing through the intermediate flow passage, the material having a non-uniform radial thickness about the axis.
In some embodiments, the inner outlet, the intermediate outlet, and the outer outlet are immediately adjacent to one another.
In some embodiments, the inner nozzle insert is formed such that the intermediate outlet extends only partially around a longitudinal axis of the hot runner nozzle.
In some embodiments, the inner nozzle insert has an outer surface that partially defines the intermediate flow channel; and the outer surface has an elliptical form with the center of the elliptical form surface offset from the longitudinal axis of the hot runner nozzle.
In some embodiments, the inner outlet and the outer outlet are arranged concentrically.
In some embodiments, the intermediate outlet is disposed between a portion of the concentrically arranged inner and outer outlets.
In some embodiments, in use, a first melt stream of a first polymeric material flows through and out of the inner and outer flow channels when the melt is transferred into the mold cavity; a second melt stream of a second polymeric material flows through and out of the intermediate flow channel, the second polymeric material forming a core layer of a molded product produced from the melt in the mold cavity; and the first melt stream and the second melt stream intersect at a junction region.
In some embodiments, the mold cavity is for defining, in use, a molded article having a core layer and a skin layer surrounding the core layer, the core layer being formed of a second polymeric material flowing through the intermediate flow channel, the core layer having a non-uniform radial thickness about a longitudinal axis of the molded article.
According to yet another broad aspect of the present technique, there is provided a hot runner nozzle for delivering melt to a mold cavity. The hot runner nozzle includes an inner nozzle insert defining an inner flow passage; an intermediate nozzle insert disposed about the inner nozzle insert, the intermediate nozzle insert and the inner nozzle insert defining an intermediate flow channel; and an outer nozzle insert disposed about the intermediate nozzle insert, the outer nozzle insert and the intermediate nozzle insert defining an outer flow channel, a flow of material through the intermediate flow channel being non-uniformly distributed about a longitudinal axis of the hot runner nozzle when the hot runner nozzle is in use, the flow non-uniformity being due to surfaces of the intermediate nozzle insert and the inner nozzle defining the intermediate flow channel, a mold cavity for defining, in use, a molded article, the molded article having a core layer and a skin layer surrounding the core layer, the core layer being formed of material flowing through the intermediate flow channel, the core layer having a non-uniform radial thickness about the longitudinal axis of the molded article.
These and other aspects and features of non-limiting embodiments of the present technology will become apparent to those skilled in the art upon review of the following description of specific non-limiting embodiments of the present technology in conjunction with the accompanying figures.
Embodiments of the present technology each have at least one, but not necessarily all, of the above objects and/or aspects. It should be appreciated that some aspects of the present technology that arise from an attempt to achieve the above objectives may not meet this objective and/or may meet other objectives not specifically recited herein.
Additional and/or alternative features, aspects, and advantages of embodiments of the present technology will become apparent from the following description, the accompanying drawings, and the appended claims.
Drawings
This patent or application document contains at least one drawing executed in color. Copies of this patent or patent application publication with color drawing(s) will be provided by the office upon request and payment of the necessary fee.
Embodiments of the present technology (including alternatives and/or variations thereof) may be better understood with reference to the detailed description of non-limiting embodiments along with the following drawings, in which:
FIG. 1 is a cross-sectional view of a multi-layer preform as known in the prior art;
FIG. 2 is a top view schematic diagram of an injection molding machine that may be adapted to produce embodiments of non-limiting embodiments of the present technique;
FIG. 3A is a longitudinal cross-sectional view of a multi-layer preform in accordance with one embodiment of the present technique;
FIG. 3B is a horizontal cross-sectional view of the multi-layer preform of FIG. 3A taken along
FIG. 4A is a longitudinal cross-sectional view of a multi-layer preform in accordance with another embodiment of the present technique;
FIG. 4B is a horizontal cross-sectional view of the multi-layer preform of FIG. 4A taken along
FIG. 5A is a longitudinal cross-sectional view of a multi-layer preform in accordance with yet another embodiment of the present technique; FIG. 5B is a horizontal cross-sectional view of the multi-layer preform of FIG. 5A taken along
FIG. 6A is a longitudinal cross-sectional view of a multi-layer preform in accordance with yet another embodiment of the present technique; FIG. 6B is a horizontal cross-sectional view of the multi-layer preform of FIG. 6A taken along
FIG. 6C is a front elevational view of a blow molded product blow molded from the preform of FIG. 6A;
FIG. 7A is a longitudinal cross-sectional view of a multi-layer preform in accordance with yet another embodiment of the present technique;
FIG. 7B is a front elevational view of a blow molded product blow molded from the preform of FIG. 7A;
FIG. 8A is a longitudinal cross-sectional view of a multi-layer preform in accordance with yet another embodiment of the present technique;
FIG. 8B is a horizontal cross-sectional view of the multi-layer preform of FIG. 8A taken along
FIG. 8C is a front elevational view of a blow molded product blow molded from the preform of FIG. 8A;
FIG. 9A is a longitudinal cross-sectional view of a multi-layer preform in accordance with yet another embodiment of the present technique;
FIG. 9B is a horizontal cross-sectional view of the multi-layer preform of FIG. 9A taken along line 9B-9B of FIG. 9A;
FIG. 9C is a front elevational view of a blow molded product blow molded from the preform of FIG. 9A;
FIG. 10 is a longitudinal cross-sectional view of a multi-layer preform in accordance with yet another embodiment of the present technique;
FIG. 11 is a longitudinal cross-sectional view of a multi-layer preform in accordance with yet another embodiment of the present technique;
FIG. 12 is a cross-section of a hot runner nozzle (the cross-section being taken along an operational axis of the hot runner nozzle) suitable for implementing embodiments of the present technique;
FIG. 13 is a cross-section of the hot runner nozzle of FIG. 12 taken along line 13-13 of FIG. 12, the hot runner nozzle being configured for producing preforms having a core radial thickness that does not vary about an operating axis;
FIG. 14 is a cross-section of the hot runner nozzle of FIG. 12 taken along line 13-13 of FIG. 12, the hot runner nozzle being configured to produce preforms having a core layer radial thickness that varies about an operating axis;
15A-15D illustrate the sequence of valve stem repositioning to selectively undulate the core layer, the repositioning of the valve stem serving to form the shape of the core layer, in some non-limiting embodiments of the present technique;
FIG. 16A is a photograph produced by a backlit optical comparator of a cross-section of another non-limiting embodiment of a molded article according to the present techniques;
FIG. 16B is a line drawing representation of the cross-section of FIG. 16A;
fig. 16C is a bottom plan view photograph of the molded article of fig. 16A;
FIG. 16D is a line drawing representation of the photograph of FIG. 16C;
FIG. 17 is a cross-section of another embodiment of a hot runner nozzle (the cross-section being taken along an operational axis of the hot runner nozzle) suitable for implementing embodiments of the present technique;
FIG. 18 is a perspective view of a middle nozzle insert of the hot runner nozzle of FIG. 17;
FIG. 19 is a side view of another embodiment of an intermediate nozzle insert of a hot runner nozzle, the nozzle insert and hot runner nozzle being suitable for practicing embodiments of the present invention;
FIG. 20 is a cross-sectional view of the middle nozzle insert of FIG. 19 taken along line 20-20 of FIG. 19;
FIG. 21 is a perspective view of the intermediate nozzle insert of FIG. 19;
FIG. 22 is a side view of an intermediate nozzle insert of yet another embodiment of an intermediate nozzle insert of a hot runner nozzle, the nozzle insert and hot runner nozzle being suitable for practicing embodiments of the present technique;
FIG. 23 is a cross-sectional view of the middle nozzle insert of FIG. 22 taken along line 23-23 of FIG. 22;
FIG. 24 is a side view of yet another embodiment of an intermediate nozzle insert of a hot runner nozzle, the nozzle insert and hot runner nozzle being suitable for practicing embodiments of the present technique;
FIG. 25 is a cross-sectional view of the middle nozzle insert of FIG. 24 taken along line 25-25 of FIG. 24;
FIG. 26 is a cross-section of yet another embodiment of a hot runner nozzle (the cross-section being taken along an operational axis of the hot runner nozzle) suitable for implementing embodiments of the present technique;
FIG. 27 is a cross-sectional view of an intermediate nozzle insert of the hot runner nozzle (the cross-section being taken along the operational axis of the hot runner nozzle) illustrating various orifice embodiments;
FIGS. 28 and 29 are perspective views of an embodiment of an inner nozzle insert of a hot runner nozzle suitable for practicing embodiments of the present technique;
FIG. 30 is a bottom plan view of the inner nozzle insert of FIG. 28; and
FIG. 31 is a cross-sectional view of the inner nozzle insert of FIG. 28 disposed in a hot runner nozzle, taken along line 31-31 of FIG. 30.
Detailed Description
Referring to fig. 1, a cross-section of a molded
The
On the outside, the
The
As will be described below, each
The skin layers 20, 25 surround the
Referring to FIG. 2, which illustrates a non-limiting embodiment of the
As seen in fig. 2, the
The
In operation, the moving
The
The
Furthermore, the
The
FIG. 2 shows the
It should be appreciated that one of the first and second mold halves 114, 116 may be associated with a plurality of additional mold elements, such as one or more guide pins (not shown) and one or more guide sleeves, which cooperate to assist in aligning the first and second mold halves 114, 116 in the mold closed position, as known to those skilled in the art.
The
Generally, the plurality of molded
A
The
The
Those skilled in the art will appreciate that the
In an alternative non-limiting embodiment of the present technology, the HMI need not be physically attached to the
The
Various non-limiting embodiments of molded articles according to the present techniques will be discussed with reference to fig. 3A through 11. It should be noted that in the
Referring to fig. 3A-3B, a molded
On the outside, the
As shown in fig. 3A-3B, at least a majority of the
The
Variation in the radial thickness of the
The
More specifically, defined in
The branches of the first material
First material
A second
All of first material
More specifically, the
In some non-limiting embodiments of the present technology, the
Referring to FIG. 13, a cross-section of
Referring to fig. 14, which shows a modified version of
Specifically, the outer surface of first nozzle insert 1206 (partially defining second material nozzle channel 1218) has an elliptical form, wherein the center of the elliptical form surface is offset from the longitudinal axis of
Additionally or alternatively, the shape and/or arrangement of the
In the fig. 15A illustration,
In the fig. 15B illustration, the
In the fig. 15C illustration, the
In the fig. 15D illustration,
In some embodiments, the first and second materials are selected such that the thermal crystallization rate of the first polymeric material is substantially less than the thermal crystallization rate of the second polymeric material. In some other embodiments, the second polymeric material has a substantially higher intrinsic viscosity than the first polymeric material. These embodiments will be discussed in more detail below with reference to fig. 10 and 11.
In any such embodiment, the different blow molding characteristics of the two different materials of the skin layers 320, 325 and the
With reference to fig. 4A-4B, a
The
On the outside, the
As shown, the radial thickness of the
Control of the shape and/or arrangement of
Variation in the radial thickness of the
With reference to fig. 5A-5B, a
The
As with the
Control of the shape and/or arrangement of
Variation in the radial thickness of the
With reference to fig. 6A-6C, a
The
The
Broadly speaking, a non-limiting embodiment of
An example of a blow molded
Control of the shape and/or arrangement of
Referring to fig. 7A-7B, a
The
As with the
In this embodiment, the radial thickness of the
Control of the shape and/or arrangement of
With reference to fig. 8A-8C, a
The
As with the
The
In fig. 8C a blow molded product 801 made from a
Control of the shape and/or arrangement of interrupted
With reference to fig. 9A-9C, a multi-layer preform 900 in accordance with another non-limiting embodiment of the present technique will be described. The multi-layer preform 900 is manufactured by the
The multi-layer preform 900 includes a body portion 934 formed of three layers; the remainder of the preform 900 is substantially similar to the
The body portion 934 of the preform 900 includes a transition portion 935 extending between the neck portion 932 and the body portion 934. The transition portion 935 includes a transition inner layer 925 and a transition outer layer 920 of a first polymeric material. The transition 935 further includes a transition core layer 940 of a second polymeric material disposed between at least a portion of the layers 920, 925. The core layer 940 is an interrupted layer 940. The interrupted layer 940 is made up of a plurality of cores 941; the layers 920, 925 make contact at a location where the radial thickness of the transition core layer 940 is reduced to zero (between cores 941).
In fig. 9C a blow molded
Control of the shape and/or arrangement of the interrupted core layer 940 can be implemented similarly to the shape and/or arrangement of the
Referring to fig. 10, a molded article 1000 in accordance with another non-limiting embodiment of the present technique will be described. The molded article 1000 (also referred to as a multi-layer preform 1000) is manufactured by the
Preform 1000 includes a neck portion 1032, a body portion 1034 and a gate portion 1036 as described with respect to preform 50. Body portion 1034 includes skin layers 1020 and 1025 and core layer 1040. Although the core layer 1040 is shown as a rotationally symmetric core form of the
Both the inner outer skin 1020 and the outer skin 1025 are formed from a first polymeric material that is a non-strain hardening material. The material of the skin layers 1020, 1025 may be selected from, but not limited to, High Density Polyethylene (HDPE) and polypropylene (PP).
Core layer 1040 is formed from a second, different polymeric material. In this embodiment, the first and second materials are selected such that the thermal crystallization rate of the first polymeric material is substantially less than the thermal crystallization rate of the second polymeric material. In particular, core layer 1020 is made of a strain hardening material, which may include, but is not limited to, homopolymers, copolymers, and blends of strain crystallizable polyethylene terephthalate (PET). By including a strain-hardened material as the core layer 1040, the preform 1000 may utilize a non-strain-hardened material, which may have preferred aesthetic and cost characteristics, while the strain-hardened core layer 1040 provides the strength lacking in the skin layers 1020, 1025.
In this non-limiting embodiment, neck 1032 is also made of a non-strain hardened material, although in some non-limiting embodiments it is contemplated that neck 1032 may be made of the same material as core layer 1040, or even a third different material.
Control of the shape and/or arrangement of core layer 1040 may be implemented similarly to the shape and/or arrangement of
Referring to fig. 11, a molded
Both inner
In this non-limiting embodiment, the
Control of the shape and/or arrangement of
Referring to fig. 16A-16D, a molded
The
In some other non-limiting embodiments of the
With reference to fig. 17 and 18, the
Hot-
Both
When the
The core material passing through the
It is contemplated that the
With reference to fig. 19-21, another non-limiting embodiment of a hot runner nozzle design will now be described, which specifically includes an
In this non-limiting embodiment, the
By controlling the flow rate, it is also contemplated that the degree of core layer radial thickness variation can be controlled. For example, varying the flow rate through a particular cycle may produce additional variations in the local core radial thickness in the machine direction.
With reference to fig. 22 and 23, another non-limiting embodiment of a hot runner nozzle design, specifically an intermediate nozzle insert 1558, will now be described for producing at least some of the preform designs presented above. Although not specifically illustrated, intermediate nozzle insert 1558 may be used in place of
In a non-limiting embodiment of the intermediate nozzle insert 1558, the hot runner nozzle includes a total of 20 orifices for fluidly connecting the intermediate flow channel to the outer flow channel. The
As can be seen in this non-limiting embodiment, the apertures 1580 need not all be arranged at the same angle relative to the operational axis. The apertures 1580 also need not be equally spaced, as can be seen from at least the top two apertures 1580 along each longitudinal line. It is contemplated that intermediate nozzle insert 1558 may include more or fewer orifices, depending on the particular embodiment.
With reference to fig. 24 and 25, another non-limiting embodiment of a hot runner nozzle design, in particular an
In a non-limiting embodiment of the
As shown in fig. 4A and 4B, the resulting core layer is slightly thickened along a wide portion of the core layer circumference.
In some embodiments, the
Referring to fig. 26, an illustrative example of a
Both
Similar to the hot runner nozzles described above,
Referring to fig. 27, an illustrative example of a
As described at least with respect to
The apertures used may be of different forms depending on various factors. These factors may include, but are not limited to: the nature of the particular material used in the skin layer, core layer, or both; different cycle parameters of the nozzle when in use; and the desired amount of change in the radial thickness of the core layer.
In some embodiments, the apertures may be generally cylindrical and angled, such as
The selection of one or more of the orifices 1802-1816 described above may depend on various factors, including the extent to which the core is to be altered, e.g., or the core material passing through the outer flow channel is to penetrate the outer skin or closer to the surface of the preform being manufactured. It is also contemplated that the orifice may be further varied, such as by having a larger or smaller diameter than shown. The relative spacing, orientation, and location of the different apertures may further vary according to particular embodiments. During use, it is also contemplated that any of the rod position, injection speed and injection timing, as well as other process variables, may be controlled to affect different preforms being manufactured. It should be noted that various methods may be utilized to form the orifice including, for example, electro-discharge machining and 3D printing of the nozzle insert, although fabrication of the present technology is not meant to be so limited.
These are non-limiting examples of different orifices that may be defined in at least one of the intermediate nozzle insert and the inner nozzle insert, but other different forms may also be implemented. According to embodiments, one or both of the intermediate nozzle insert and the inner nozzle insert may comprise as few as one aperture up to a plurality of apertures. It is also contemplated that in some embodiments, multiple forms of apertures 1802-1816 (or other forms) may be implemented in a single embodiment.
Additionally, the shape and/or arrangement of the preform core layer manufactured using the hot runner nozzle or
With reference to fig. 28-31, another non-limiting embodiment of a hot runner nozzle 1900, specifically an
The hot runner nozzle 1900 includes an
As can be seen in the figures, the
As shown, the intermediate outlet 1920 and the outer outlet 1924 are immediately adjacent to one another. Specifically, the inner outlet 1922 and the outer outlet 1924 are concentrically arranged. Due to the form of the
The
In some non-limiting embodiments, it is contemplated that portions of the passages 1916, 1918 may be modified to compensate for flow imbalances in the passages 1916, 1918 due to their non-uniform nature. For example, in some embodiments, the outer flow channels 1916 may be thinner in the portion around the axis defining the intermediate flow channels 1918, such that the total flow from the channels 1916, 918 has a similar or the same total flow as the portion of the nozzle 1900 not defining the intermediate flow channels 1918, and all flow is from the outer flow channels 1916 only. It is also contemplated that the form of the passages 1916, 1918 may be varied to equalize the pressure across the nozzle 1900 during use.
Broadly speaking, non-limiting embodiments of hot runner nozzles and nozzle inserts for delivering melt to the mold cavities described above are designed to deliver core layer material such that the molded articles produced in the mold cavities have a non-uniform radial thickness about the longitudinal axis of the molded articles. In particular, when a hot runner nozzle is used, the flow of material through the intermediate flow channel is non-uniformly distributed about the longitudinal axis of the hot runner nozzle. Flow non-uniformity is generally attributed to the surfaces of the inner nozzle and the intermediate nozzle insert defining the intermediate flow channel. In some of the above embodiments of the present technology, the surface defines an aperture through which the core material passes to create a locally increased core thickness. In other embodiments of the present technology, the surfaces form intermediate flow channels that do not extend uniformly about the hot runner nozzle axis, such that the core material is not distributed uniformly around the molded article.
It should be noted that even though the core layers shown in the various embodiments of the present technique are not completely encapsulated in (i.e., interrupted in) the gate portion of the preform, in alternative non-limiting embodiments of at least those preforms shown in fig. 3A, 4A, 8A, 10, 11, and 16A-D, the individual core layers may be completely encapsulated (i.e., continuous) in the gate portion of the preform.
The polymeric materials of any of the foregoing non-limiting embodiments for forming the
The polymeric materials of the foregoing non-limiting embodiments used to form the
Modifications and improvements to the above-described embodiments of the present technology will be apparent to those skilled in the art. The foregoing description is exemplary rather than limiting in nature. Accordingly, the scope of the present technology is to be limited only by the scope of the following claims.
The description of the embodiments of the present technology provides only examples of the present technology, and these examples do not limit the scope of the present technology. It should be clearly understood that the scope of the present technology is defined only 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 technology.
Having thus described embodiments of the present technology, it will be apparent that modifications and enhancements are possible without departing from the concepts as described.