GB2544508A

GB2544508A - Plastics moulding apparatus and method

Info

Publication number: GB2544508A
Application number: GB1520359.9A
Authority: GB
Inventors: Keith Showering Francis
Original assignee: Individual
Current assignee: Individual
Priority date: 2015-11-18
Filing date: 2015-11-18
Publication date: 2017-05-24
Also published as: GB201520359D0

Abstract

An apparatus and method for moulding a plastics container closure article comprising a collapsible core mould tool having a first and second mould tool surface, wherein the collapsible core mould tool is transformable between an expanded configuration for moulding and a collapsed configuration having a smaller outer periphery than in expanded mode; first and second mould cavities that engage with the collapsible mould core wherein the first mould cavity is in relation with the first mould tool surface, and the second mould cavity is in relation with the second mould tool surface. The apparatus will preferably have a transfer device that will enable a moulded lid to be transferred from a first mould cavity to a second mould cavity. The method will preferably comprise of moulding a first portion, in the first cavity positioned relative to the first surface region on the collapsible core mould tool and, moulding a second portion in a second cavity positioned relative to the second mould tool region of the same collapsible core mould tool.

Description

PLASTICS MOULDING APPARATUS AND METHOD Field of the Disclosure

The present disclosure relates to the field of plastics moulding, to moulding apparatus, and to articles produced or manufactured thereby. Although not limited, some aspects of the disclosure may be suitable for moulding an article such as a closure for a container. Although not limited, some aspects of the disclosure may be suitable for moulding an article comprising first and second components in assembled relation.

Background to the Disclosure

An injection moulding apparatus including a so-called "collapsible core" mould tool may be used for moulding articles that include interior detail, for example, a container closure with an undercut interior profile. After moulding, the collapsible core mould tool collapses inwardly to enable the moulded article to be ejected away from around the core, without damaging the interior detail. However, a collapsible core mould tool is relatively expensive and adds significantly to the manufacturing cost per article.

Where such an article is made of multiple component parts, multiple collapsible core mould tools may be required, one for each component part to be moulded. This further adds to the manufacturing cost.

Multiple component articles may also be moulded by so-called "assembly injection moulding" in which the multiple components are moulded together, in assembled relation, in the same moulding apparatus. Known assembly injection moulding apparatus includes multiple mould tools, and robotic apparatus to move the mould tools and to transfer the article between moulding stations, for moulding each component sequentially in assembled relation.

However, such apparatus is additionally expensive, adding further to the manufacturing costs. The problem of high cost is exacerbated for an article such as a multi-component container closure. Assembly injection moulding apparatus requiring multiple collapsible core mould tools is complex and particularly expensive.

The manufacturing cost of a generally cheap article, such as a container closure, may be important to the commercial adoption and success of the article. It may also (i) limit the extent to which expensive moulding technologies, such as assembly injection moulding, may be viable; and (ii) hinder development of new designs.

The present invention has been devised bearing the above issues in mind. It may be desirable to alleviate one or more of the above issues.

Summary of the Disclosure

The following summary is intended to provide a non-limiting summary of some of the ideas described in the current disclosure.

Some aspects of the disclosure are defined in the appended claims.

Additionally or alternatively, in one aspect of the present disclosure, moulding apparatus is provided for moulding a plastics article (optionally but not limited to being a container closure).

The article may comprise first and second portions that are distinct from one another and/or are moulded in separate moulding steps.

In some examples, the first and second portions are coupled together by inter-engagement with each other.

In some examples, the article is a multi-component article, and the first and second portions are first and second components of the article. As used herein, the term "multi-component" refers to an article comprised of first and second components that are at least partly separable and/or at least partly movable with respect to each other, at least after and/or with suitable manipulation.

The moulding apparatus may include any one or any combination of two or more of the following features, in any combination, and all of which are optional: (a) The moulding apparatus may include a collapsible core mould tool.

As used herein the term "collapsible core mould tool" refers to a mould tool transformable between (i) a first expanded configuration presenting a mould tool surface around which at least a portion of an article or component is moulded; and (ii) a second collapsed configuration having a smaller outer periphery than the expanded configuration to facilitate separation of the moulded article or component from the mould tool. (b) The moulding apparatus may define first and second mould cavities around the same collapsible core mould tool. (c) The first and second mould cavities may be at least partly different in shape from each other, for moulding different article portions (e.g. components), and/or for over-moulding in one cavity an article portion (e.g. component) previously moulded in the second cavity.

As used herein, the term "over-moulding" refers to moulding a first portion (e.g. component) in contact with a second portion (e.g. component) that has already been formed, whatever the positional relationship between the first and second portions (for example, under, over, outside, and/or inside).

Optionally, for a multi-component article, one component is over-moulded in assembled relation with a second component that has already been moulded in the other cavity. (d) The first mould cavity may correspond to a first component of a multi-component article. Additionally or alternatively, the second mould cavity may correspond to a second component of the multi-component article, optionally in assembled relation with the first component. (e) The first mould cavity may be smaller than the second mould cavity. Optionally, the first mould cavity may be referred to as a "small" mould cavity, and second mould cavity may be referred to as a "large" mould cavity. (f) The collapsible core mould tool may include a first mould tool surface region corresponding to a region (e.g. an interior region) of the first mould cavity, and second mould tool surface region corresponding to a region (e.g. an interior region) of the second mould cavity. (g) The first mould tool surface region may be offset from the second mould tool surface region in an axial direction of the collapsible core mould tool. (h) The collapsible core mould tool may include a partition wall projection between the first and second mould tool surface regions. The partition wall projection may correspond to a partition wall between the first and second mould cavities. (i) In the expanded configuration, the first and second mould tool surface regions (and optionally the partition wall projection if provided) may be presented radially outwardly for defining respective surface regions of the first and second mould cavities. (j) In the collapsed configuration, the first and second mould tool surface regions (and optionally the partition wall projection if provided) may be collapsed inwardly, for example, substantially concurrently with each other. (The surface regions may nevertheless still be referred to as mould tool surface regions in this configuration, even though the collapsed configuration of the collapsible core mould tool might not be suitable for moulding.) (k) The collapsible core mould tool may comprise plural tool surface region bearing segments that are relatively movable with respective to one another during transformation of the collapsible core mould tool between the expanded and collapsed configurations. (l) At least one of the segments, optionally plural segments, optionally a majority of the segments, optionally all of the segments, include(s) both a respective portion of the first mould tool surface region and a respective portion of the second mould tool surface region (and optionally a respective portion of the partition wall projection if provided. (m) The moulding apparatus may be configured to transfer a moulded article portion (e.g. component) from the first mould tool surface region to the second mould tool surface region, optionally while the collapsible core mould tool is in the collapsed configuration. (n) Additionally or alternatively, the moulding apparatus may be configured to transfer a moulded portion (e.g. component) from the first cavity to the second cavity, optionally while the collapsible core mould tool is in the collapsed configuration. (o) The first mould cavity may be generally annular in shape. (p) The second mould cavity may be generally cup-shaped (e.g. having an annular region and a region bridging or spanning the annular region). (q) The moulding apparatus may be configured for moulding components in the first and second cavities generally concurrently with each other, optionally while the collapsible core mould tool is in the expanded configuration. (r) The moulding apparatus may comprise an outer mould tool defining at least partly the first and/or second mould cavity. (s) The collapsible core mould tool and the outer mould tool may be movable one relative to the other, in a generally axial direction of the collapsible core mould tool. (t) The collapsible core mould tool and the outer mould tool may be movable one relative to the other, for transferring a moulded component from the first cavity to the second cavity. (u) The outer mould tool and the collapsible core mould tool may be movable relative to each other, between a first relative position in which the outer mould tool is generally in register with the first mould tool surface region, and a second relative position in which the outer mould tool is generally in register with the second mould tool surface region. (v) The outer mould tool may comprise a retainer for retaining a moulded portion (e.g. component) with respect to the outer mould tool, at least temporarily, for transferring the moulded portion to the second mould cavity. (w) The collapsible core mould tool and the outer mould tool may cooperate as male and female portions defining (e.g. at least partly) at least one of the mould cavities.

Additionally or alternatively to any of the above, a further aspect of the present disclosure may provide moulding apparatus comprising: a collapsible core mould tool; an enclosing mould tool that cooperates with the collapsible core mould tool to define a mould cavity ("second" or "large" mould cavity); and a stripper unit extending around a portion of the collapsible core mould tool, and movable axially with respect to the collapsible core mould tool and/or the enclosing mould tool for directly or indirectly discharging a moulded article from one or more selected from: the mould cavity; the collapsible core mould tool; the enclosing mould tool; wherein the stripper unit cooperates with the collapsible core mould tool to define a further mould cavity ("first" or "small" mould cavity) for moulding therein a component during the same mould cycle in which an article is moulded in the (second) mould cavity.

In some embodiments, an article or component (such as the component moulded in the further mould cavity) carried by the stripper unit may be used to bear on a moulded article for discharging the moulded article. This may be referred to as the stripper causing discharge of the moulded article indirectly.

Additionally or alternatively to any of the above, a further aspect of the present disclosure may provide apparatus for moulding a plastics container closure article, comprising: a collapsible core mould tool having a first mould tool surface region and a second mould tool surface region, the collapsible core mould tool being transformable between an expanded configuration presenting the mould tool surface regions for a moulding operation, and a collapsed configuration having a smaller outer periphery than the expanded configuration; first and second mould cavities defined around the same collapsible core mould tool, the first mould cavity being defined around the first mould tool surface region, and the second mould cavity being defined around the second mould tool surface region.

Additionally or alternatively to any of the above, a further aspect of the present disclosure may provide apparatus for moulding a plastics container closure article, comprising: a collapsible core mould tool having a first mould tool surface region and a second mould tool surface region offset from one another in an axial direction of the collapsible core mould tool, the collapsible core mould tool being transformable between an expanded configuration presenting the mould tool surface regions for a moulding operation, and a collapsed configuration having a smaller outer periphery than the expanded configuration; a transfer device for transferring an article or component from the first mould tool surface region to the second mould tool surface region, the transfer device comprising an outer mould tool extending around an exterior of the collapsible core mould tool, wherein the outer mould tool and the collapsible core mould tool are movable relative to each other between at least a first relative position in which the outer mould tool is positioned generally in register with the first mould tool surface region, and a second relative position in which the outer mould tool is positioned generally in register with the second mould tool surface region.

Additionally or alternatively to any of the above, a further aspect of the present disclosure provides a method of manufacturing a moulded article (optionally but not limited to being a container closure).

In some examples, the article is a multi-component article, and the first and second portions are first and second components of the article.

The method may comprise any one or any combination of two or more of the following features and/or steps, in any combination, and all of which are optional: (a) The method may optionally comprise using moulding apparatus as defined with any of the features above. (b) The method may comprise moulding first and second portions (e.g. components) of the article around first and second (e.g. different) mould tool surface regions of the same collapsible core mould tool. (c) The method may comprise moulding first and second portions (e.g. components) of the article around first and second (e.g. different) mould tool surface regions of a collapsible core mould tool that has both the first and second mould surface regions. (d) The first and second mould tool surface regions may be offset from each other in an axial direction of the collapsible core mould tool. (e) The method may comprise transferring a portion of the article (e.g. a component) from the first mould tool surface region to the second mould tool surface region. (f) The method may comprise collapsing the collapsible core mould tool to permit (i) transfer of a component (or partly moulded article) from the first mould tool surface region to the second mould tool surface region, and/or (ii) removal of a component (or partly or fully moulded article) from the second mould tool surface region. (g) The method may comprise moulding around respective regions of the same collapsible core mould tool, a first component of a first article and a second component of a second article. (h) The first component of the first article may be moulded substantially concurrently with the second component of the second article (or at least the two components may be moulded during the same interval between consecutive collapsing operations for the collapsible core mould tool).

In a further aspect, apparatus and/or a method is provided for moulding a plastics container closure article comprising first and second portions (e.g. components) in assembled relation. The first and second portions may be moulded in first and second cavities defined around first and second mould tool surface regions of the same collapsible core mould tool. A first portion may be transferred from the first mould cavity to the second mould cavity for over-moulding in the second cavity. Optionally, a first portion of a subsequent article is moulded in the first mould cavity during the same mould cycle as the over-moulding of a previously formed first portion.

Additionally or alternatively to any of the above, a further aspect of the present disclosure may provide a method of moulding a plastics container closure article, comprising the steps of: moulding a first portion of the article in a first mould cavity defined around a first mould tool surface region of a collapsible core mould tool; and moulding a second portion of the article in a second mould cavity defined around a second mould tool surface region of the same collapsible core mould tool.

Additionally or alternatively to any of the above, a further aspect of the present disclosure may provide a method of moulding a plastics container closure article and/or a method of operation of a moulding apparatus for moulding a plastics container closure article, comprising the steps of: moulding, in a first mould cycle, a first portion of the article in a first mould cavity defined around a first mould tool surface region of a collapsible core mould tool while the collapsible core mould tool is in an expanded configuration; transitioning the collapsible core mould tool to a collapsed configuration; transferring the first portion from the first mould tool surface region to a second mould tool surface region of the same collapsible core mould tool; transitioning the collapsible core mould tool to the expanded configuration; over-moulding, in a second mould cycle, and in a second mould cavity defined around the second mould tool surface region, a second portion of the article with respect to the first portion; and transitioning the collapsible core mould tool surface region to the collapsed configuration for discharging the article from collapsible core mould tool.

Additionally or alternatively to any of the above, a further aspect of the present disclosure may provide a method of moulding plastics container closure articles, and/or a method of operation of an apparatus for moulding plastics container closure articles, comprising the steps of: during a mould cycle, moulding in first and second cavities defined around first and second mould tool surface regions of the same collapsible core mould tool, first and second portions of respective articles; and between mould cycles: transitioning the collapsible core mould tool to a collapsed configuration; discharging a moulded article from the second mould tool surface region; transferring a moulded first portion from the first mould tool surface region to the second mould tool surface region; and transitioning the collapsible core mould tool to an expanded configuration.

The present disclosure and protection claimed also extends to an article moulded directly or indirectly by any of the above apparatus and/or methods.

Although certain features and ideas have been discussed above and/or in the appended claims, protection is claimed for any novel feature or idea disclosed herein and/or illustrated in the drawings, whether or not emphasis has been placed thereon.

Brief Description of the Drawings

Fig. 1 is a schematic section showing an example moulding apparatus in a first condition.

Fig. 2 is a schematic section similar to Fig. 1 showing the apparatus in a second condition.

Fig. 3 is a schematic section similar to Fig. 1 showing the apparatus in a third condition.

Fig. 4 is a schematic section similar to Fig. 1 showing the apparatus in a fourth condition.

Fig. 5 is a schematic section similar to Fig. 1 showing the apparatus in a fifth condition.

Fig. 6 is a schematic section similar to Fig. 1 showing the apparatus in a sixth condition.

Fig. 7 is a schematic cross-section through the collapsible core mould tool part in an expanded configuration.

Fig. 8 is a schematic cross-section through the collapsible core mould tool part in a collapsed configuration.

Fig. 9 is a schematic cross-section showing a detail "IX" of Fig. 8.

Fig. 10 is a schematic cross-section showing a detail "X" of Fig. 4.

Fig. 11 is a schematic cross-section through a second embodiment of moulding apparatus.

Fig. 12 is a schematic perspective view of an example multi-component container closure.

Fig. 13 is a schematic section through the closure of Fig. 12.

Fig. 14 is a perspective view showing in isolation the inner component of the closure of Fig. 12.

Fig. 15 is a perspective view showing in isolation the outer component of the closure of Fig. 12.

Fig. 16 is a schematic section though a second example of closure.

Detailed Description of Preferred Embodiments

Non-limiting embodiments of the disclosure are now described by way of example only, with reference to the accompanying drawings, in which the same numerals are used to denote the same or equivalent features as appropriate. Any references to direction are merely labels with reference to the drawings, it being understood that the apparatus may be used in any suitable orientation, and that may be different from that illustrated. Typically, the mould is used on its side as illustrated.

Firstly, Figs. 12-15 illustrate an example article 100 mouldable using some techniques described in the present disclosure, so that the difficulty of moulding such a complicated article can be appreciated. The article 100 is illustrated in the form of a closure 102, for example, for a container mouth, but the article is not limited only to closures. The article 100 is illustrated to be generally round in shape, but the article 100 is not limited only to round shapes. The article 100 is illustrated in the form of a multi-component article, but the article is not limited only to multi-component articles.

In the illustrated example, the article 100 may comprise at least a first portion 104 in the form of a first component, and a second portion 106 in the form of a second component. As illustrated below in Fig. 16, the principles of the present disclosure may also be applied to a single component article, for example, including two portions moulded one after another whether or not integral after moulding. In the following description, terms relating to article portion and component are intended to be read interchangeably whether or not both terms are used explicitly.

The first portion (e.g. component) 104 may be the radially outer of the two, although the positioning may be swapped. Additionally or alternatively, the first and second portions (e.g. components) 104 and 106 may be coupled together by mechanical inter-engagement of the portions with each other. Optionally, the second portion (e.g. component) 106 may have an inverted cup-shape, including an annular side wall closed at its upper end by top wall. Additionally or alternatively, the first portion (e.g. component) 104 may have a generally annular shape extending around the side wall of the second portion (e.g. component) 106.

At least one, and optionally both, of the portions 104 and 106 may comprise interior detail, for example, a discontinuous and/or non-flat interior surface. For example, the first portion 104 may include a discontinuous surface including a circumferential array of teeth 108 inter-fitting exactly with complementary apertures and pockets 114 of the second portion 106.

The second portion 106 may include a discontinuous interior surface with a circumferentially extending clearance 110, and/or may include an undercut interior fastener rib 112.

Fig. 16 illustrates an example single component article 100 in the form of a screw-threaded closure 102, optionally for a container. The closure 102 includes a first portion 104 and a second portion 106 in similar relation to the preceding closure, except that in this example the two portions 104 and 106 may be bonded and/or integrally moulded as an integral one-piece article. The portions 104 and 106 may be of the same or different plastics as each other.

The features and design of the illustrated articles 100 are not limiting, but serve to show design detail of an article 100 that is difficult to manufacture in a cost-efficient manner, especially if the article 100 is intended as a container closure 102 (for example, a low-cost disposable item).

Figs. 1 to 10 illustrate an example moulding apparatus 10 that may be used to manufacture plastics articles (for example, but not limited to, the articles 100 described above).

In some embodiments, the moulding apparatus 10 may be an assembly moulding apparatus for moulding multiple portions and/or components of an article in assembled relation to each other.

The moulding apparatus 10 includes a collapsible core mould tool 12. The tool 12 is transformable between an expanded configuration (as seen in Figs. 1, 2, 5, 6 and 7) and a collapsed configuration (as seen in Figs. 3, 4 and 8).

The moulding apparatus 10 may comprise a first mould cavity 14 and a second mould cavity 16 around the (e.g. same) collapsible core mould tool 12. The collapsible core moulding tool 12 may comprise a first mould tool surface region 18 corresponding to a region of the first mould cavity 14, and a second mould tool surface region 20 corresponding to a region of the second mould cavity 16.

As explained in further detail below, such a design enables a single (or at least the same) collapsible core mould tool 12 to be used for moulding plural portions of an article, such as plural components of a multi-component article, even where multiple components have interior detail that would, using conventional mould tools, require multiple and separate collapsible core mould tools, and a robot for transferring a component from one collapsible core mould tool to another.

The first mould cavity 14 may be smaller than the second mould cavity 16. The first mould cavity 14 may be referred to as a "small" cavity, and the second mould cavity as a "large" cavity.

The first mould tool surface region 18 may be offset from the second mould tool surface region 20 in an axial direction of the collapsible core mould tool 12. For example, the second mould tool surface region 20 may be distal of the first mould tool surface region 18.

The collapsible core mould tool 12 may further include a partition wall projection 22 between the first and second mould tool surface regions 18 and 20. The partition wall projection 22 may separate the two mould tool surface regions 18 and 20. A generally ring-shaped outer mould tool 24 surrounds and is axially movable relative to the collapsible core mould tool 12. As explained below, the outer mould tool 24 may serve any one, two or all three of the following functions: (i) to define at least partly the first mould cavity 14; (ii) to transfer a moulded first portion 104 (e.g. component) from the first mould cavity 14 to the second mould cavity 16; and/or (iii) to cause, directly or indirectly, discharge (or ejecting or stripping) of a moulded article from the second mould cavity 16.

These functions are described in more detail below.

The first mould cavity 14 may be defined (e.g. at least partly) by the first mould tool surface region 18 proximal to the partition wall projection 22, and an inner surface of the outer mould tool 24 extending around the first mould tool surface region 18. The first mould cavity 14 may, for example, be generally annularly shaped and/or ring shaped. The first mould cavity 14 may optionally be configured for moulding the first portion (e.g. component) 104 of the closure 102 of Fig. 11. The first mould tool surface region 18 may optionally be configured for moulding the interior detail of the first portion (e.g. component) 104.

The second mould cavity 16 may be defined (e.g. at least partly) by the second mould tool surface region 20 distal of the partition wall projection 22, and an inner surface of a cover mould tool 26 extending around and over the second mould tool surface region 20. The second mould cavity 16 may further be defined (eg. at least partly) by a distal surface of a centre pin 44 described below. The second mould cavity 16 may, for example, be generally cup-shaped (e.g. including an annular region and a region bridging or spanning the annular region).

Additionally or alternatively, the second mould cavity 16 may optionally be configured for over-moulding the second portion (e.g. component) 106 of the closure 102 of Fig. 11, in assembled relation with a first portion (e.g. component) 104, e.g., that has been previously been moulded in the first cavity 14. The second mould tool surface region 20 may optionally be configured for moulding the interior detail of the second portion (e.g. component) 106.

The apparatus 10 may be configured to transfer a moulded portion (e.g. the first component) 104 from (i) the first mould cavity 14 to the second mould cavity 16, optionally while the collapsible core mould tool 12 is in the collapsed configuration; and/or (ii) from the first mould tool surface region 18 to the second mould tool surface region 20, optionally while the collapsible core mould tool 12 is in the collapsed configuration.

To transfer the moulded portion 104, the outer mould tool 24 is movable axially relative to the collapsible core mould tool 12, and a retainer is provided for retaining the moulded portion 104 to move with the outer mould tool 24 (at least in one direction of transfer movement). When the outer mould tool 24 is generally in register with the first mould tool surface region 18 of the collapsible core mould tool 12, the outer mould tool 24 may be referred to as being in a first relative position. When the outer mould tool 24 is generally in register with the second mould tool surface region 20, the outer mould tool 24 may be referred to as being in a second relative position.

Various forms of retainer are envisaged, including, by way of example only, (i) sintered ports (not shown) through which suction may be applied selectively when desired to retain the moulded portion 104 with the outer mould tool; and/or (ii) one or more selectively deployable gripper members (not shown) that, when deployed, trap the moulded portion 104 within the outer mould tool 24, and release the moulded portion 104 when retracted; and/or (iii) one or more undercut profiles 30 in the mould tool surface that create mild inter-fitting between the mould tool 24 and the moulded portion 104 sufficient to retain the moulded portion 104 temporarily.

Detail of such undercut profiles 30 is illustrated, by way of example only, in Figs. 9 and 10. The undercut profiles 30 create shallow recesses 32 in the surface of the moulded article (also visible in Figs. 12 and 15). The shallow recesses may be intended to provide only weak interaction between the outer mould tool 24 and the moulded first portion 104, which interaction can be overcome or released by blocking movement of the moulded first portion 104. As can also been seen in Fig. 10, the undercut may have, for example, a ramped and/or hooked and/or barbed shape, configured to promote retention of the moulded article 104 when the outer mould tool 24 is moved in the direction of arrow 34, and/or configured to permit disengagement of the moulded article when the outer mould tool 24 is moved in an opposite direction. Although plural spaced undercuts are illustrated, it will be appreciated that the undercuts could be made wider and/or deeper, and that a continuous annular undercut may also be used if desired.

There now follows a description of an example collapsible core mould tool 12 and an associated mover assembly 36 for completeness of understanding. However, it will be appreciated that various constructions of collapsible core mould tool 12 are known and may be used instead. In the illustrated example, the collapsible core mould tool 12 generally comprises a plurality of segments 40 and 42 (Figs. 7 and 8) arranged around a centre pin 44 (Figs. 1 to 7). Each segment carries a respective portion of the first mould tool surface region 18, a respective portion of the second mould tool surface region 20, and a respective portion of the partition wall projection 22.

In the expanded configuration (Figs. 1, 2, 5, 6 and 7), the pin 44 occupies the central space, thereby forcing the segments 40 and 42 radially outwards, to present the mould tool surface regions 18 and 20 and the partition wall projection 22. By advancing the tool 12 distally relative to the pin 44 (or retracting the pin 44 proximally from the distal end of the tool 12), the segments 40 and 42 are permitted to collapse radially inwardly to the collapsed configuration. The segments 40 and 42 may be self-biased towards the collapsed configuration, and/or an additional collapsing sleeve 46 may urge the segments 40 and 42 to collapse radially inwardly. As can be seen in Figs. 7 and 8, the segments form two groups 40 and 42, with sliding surfaces permitting the two groups of segments 40 and 42 to slide, and adopt a smaller configuration. Retracting the tool 12 back proximally with respect to the pin 44 (or advancing the pin 44 distally relative to the tool 12) again forces the segments 40 and 42 radially outwardly to the expanded configuration.

The mover assembly 36 may control the relative movement between the tool 12 and the centre pin 44, and also movement of the outer mould tool 24. The centre pin 44 may be mounted to a stationary base or clamp-plate 48, supporting a housing 50. Within the housing 50, a driver hub (or hub-plate) 52 may surround the centre pin 44 and be movable in an axial direction in response to application of an external driving force. The hub 52 may support the segments 40 and 42 of the tool 12, and the optional collapsing sleeve 46. Axial movement of the hub 52 within the housing 50 may advance and retract the tool 12 with respect to the centre pin 44, to transition the tool 12 between its collapsed and expanded configurations, respectively.

The hub 52 may also be coupled to the outer mould tool 24, for example, by one or more pins (or beams or struts) 54. The coupling includes a slack and/or lost-motion connection 56 permitting limited relative movement between the outer mould tool 24 and the hub 52, although movement of the hub 52 may thrust the outer mould tool 24 distally. The amount of relative movement may optionally be about the distance needed to transfer a moulded portion from the first mould cavity 14 to the second mould cavity 16. Additionally or alternatively, the amount of relative movement may correspond to the displacement between the first and second relative positions of the outer mould tool 24 mentioned above. A moulding cycle of the apparatus is now described to permit appreciation of certain advantages of the disclosure.

Referring to Fig. 1, at the commencement of a moulding cycle, the mould apparatus may be closed; the hub 52 retracted proximally such that the collapsible core mould tool 12 may be in its expanded configuration; and the cover mould tool 26 closed against the outer mould tool 24. The outer mould tool 24 may be in the first relative position. The first and second mould cavities 14 and 16 may thus be closed ready to receive injected plastics, and the partition wall projection 22 of the collapsible core mould tool 12 may effectively separate the first mould cavity 14 from the second mould cavity 16.

The second mould cavity 16 may be used for over-moulding a second portion (e.g. component) 106 on to an existing first portion (e.g. component) 104, and such an existing first portion 104a is illustrated in position in the second mould cavity 16. As will be appreciated from the description below, an advantage of the present disclosure is that such first portions 104 are produced and transferred to the second mould cavity 16 as an integral part of the process.

Referring to Fig. 2, plastics may be injected into the first and second mould cavities 14 and 16 to effect moulding, for example, generally simultaneously. A second article portion 106 is over-moulded on the existing first article portion 104a in the second mould cavity 16 to create a completed moulded article 100. A new first portion 104 is moulded in isolation in the first mould cavity 14.

When the article 100 is a multicomponent article, the plastics material injected in the first and second cavities may be different, incompatible plastics such that there is no (or only little) plastic bonding between the two portions (components) 104 and 106. The first and second portions (components) 104 and 106 may be coupled together by mechanical inter-fitting of the components in assembled relation. Alternatively, the temperature may be controlled to generally restrict plastic bonding if the same or compatible plastics material is used for the two components 104 and 106.

Alternatively, when the article 100 is a single-component article, the plastics material injected in the first and second cavities 14 and 16 may be the same or at least compatible plastics, to effect plastic bonding between the first and second portions 104 and 106, optionally reinforced by mechanical inter-fitting between the two portions 104 and 106.

Referring to Fig. 3, after injection of the plastics material, an initial opening of the mould apparatus 10 may take place. The cover mould tool 26 may be displaced to an open position clear of the remainder of the apparatus. The hub 52 may be advanced distally, to advance the collapsible core mould tool 12, while the moulded article 100 and the new first portion 104 remain generally about the collapsible core mould tool 12. The distal advancement of the hub 52, and tool 12 relative to the centre pin 44 may transform the mould tool 12 to its collapsed configuration, spaced radially inwardly from the moulded article 100 and new first portion 104.

The advancement of the hub 52 may also push the outer mould tool 24 to move axially generally in unison with the collapsible core mould tool 12. The outer mould tool 24 may remain in the first relative position. The outer mould tool 24 may, in effect, carry the moulded article 100 and the new first portion 104. Advancing the outer mould tool 24 axially in unison with the tool 12 can avoid any risk of unwanted axial displacement of the moulded plastics while the tool 12 is transitioning to its collapsed configuration, thereby reducing risk of accidental damage to the interior detail of the moulded plastics.

Referring to Fig. 4, the hub 52 may subsequently be driven in the opposite direction, thereby retracting the tool 12 proximally. Fig. 4 shows the apparatus partway through this motion after the hub 52 has moved a short distance, thereby retracting the tool 12 slightly proximally. The lost-motion connection 56 permits the outer mould tool 24 to remain in position without retracting with the tool 12, until the outer mould tool 24 reaches registration with the second mould tool surface region 20 (second relative position).

If the moulded article 100 has not already dropped out of the mould apparatus 10, the moulded article 100 may be discharged by the action of the outer mould tool 24 remaining in position as the mould tool 12 retracts, and optionally, by the component 104 carried by the outer mould tool 24. For example, the component 104 carried by the outer mould tool 24 may bear against the moulded article 100 to push it clear of the mould tool 12. The directional retention of the retainer 30 may prevent dislodgement of the component 104.

Alternatively, in some embodiments, the outer mould tool 24 may have a slight rake inwardly distally, such that the internal diameter at the distal end of the outer mould tool 24 is smaller than the outer diameter of the moulded article 100.

Thus the outer mould tool 24 may therefore be effective as a so-called "stripper" for directly, or indirectly, knocking or discharging the moulded article 100 from the mould apparatus 10.

Alternative means for controlling discharge of the moulded article are also envisaged, for example, by forced air current, by a dedicated ejector pin, or by temporary retention of the article in the cover mould part (optionally using an ejector pin or force air current to discharge the article therefrom).

Referring to Fig. 5, continued proximal movement of the hub 52 to the base 48 may retract the tool 12 on to the centre pin 44 thereby transitioning (e.g. returning) the tool 12 to its fully expanded configuration, while maintaining the outer mould tool 24 in axial register with the second mould tool surface region 20. It may be seen that, when the tool 12 reaches the fully expanded configuration, the partition wall projection 22 forms a ledge under the new first portion 104, firmly keeping the first portion 104 at the level of the second mould tool surface region 20.

Referring to Fig. 6, the cover mould tool 26 may be closed, pushing or returning the outer mould tool 24 back towards the housing 50. Fig. 6 shows the apparatus partway through this motion. Movement of the first portion 104 may be firmly blocked by the partition wall projection 22, thereby overcoming the weak interaction of the retainer 30. The first portion 104 may thus disengage from the outer mould tool 24. It may further be appreciated that the shallow height of the retainer 30 permits the outer mould tool 24 to be moved axially over the mould tool 12 without the retainer 30 fouling the projecting surface detail of the mould tool 12, even when the mould tool 12 is in the fully expanded configuration as illustrated.

With the mould apparatus 10 now closed, the cycle returns to the positional arrangement of Fig. 1 to repeat a new identical moulding cycle.

Fig. 11 illustrates a second example of moulding apparatus 10, configured for moulding, for example, the article 100 (screw-threaded container closure 102) of Fig. 16. The apparatus comprises the same functional parts as described for the preceding embodiment, and operates in the same manner.

It will be appreciated that the ideas of the present disclosure can provide certain significant advantages: (a) By moulding first and second portions of an article around the same collapsible core mould tool, the apparatus can be significantly less expensive than an equivalent apparatus using multiple different collapsible mould core tools, and/or a robot for transferring a moulded component or article from one collapsible core to another. (b) The apparatus need not be substantially bigger than a traditional apparatus with a single collapsible mould core (e.g. for moulding traditional single-part closures). The additional (first) mould cavity may be generally accommodated at the space occupied by a traditional "stripper" unit. (c) Since each portion or component moulded using the techniques disclosed herein may be at least partly thinner than a single-piece closure moulded in a single step, it is expected that the moulding cycle can be shorter. Reduced thickness of material may mean that less time is needed to inject the plastics, and for the plastics to set and/or cool and/or stabilize before the mould is opened to discharge the moulded article. A reduced moulding cycle can mean that apparatus can operate more quickly, producing finished moulded articles more frequently (for example, every 15 seconds instead of every 25 seconds). It will be appreciated that the time to produce each individual article is not reduced. However, by moulding a portion of the article at the same time as moulding a portion of a preceding or subsequent article, with a shorter mould cycle, the rate at which finished articles are produced can be improved. (d) The increased moulding speed may even have applications for moulding single-component articles that have no apparent need to be moulded as separate portions. By dividing the article into different portions mouldable using the techniques disclosed herein, finished articles may be produced at a faster rate than using a single mould cavity.

It is emphasized that the foregoing disclosure is merely illustrative of preferred examples, and does not limit the scope of protection. In particular, many modifications, improvements and/or equivalents may be used within the scope of the present disclosure.

Claims

1. Apparatus for moulding a plastics container closure article, comprising: a collapsible core mould tool having a first mould tool surface region and a second mould tool surface region, the collapsible core mould tool being transformable between an expanded configuration presenting the mould tool surface regions for a moulding operation, and a collapsed configuration having a smaller outer periphery than the expanded configuration; first and second mould cavities defined around the same collapsible core mould tool, the first mould cavity being defined around the first mould tool surface region, and the second mould cavity being defined around the second mould tool surface region.

2. Apparatus according to any preceding claim, further comprising a transfer device for transferring an article or component (i) from the first mould tool surface region to the second mould tool surface region; and/or (ii) from the first mould cavity to the second mould cavity.

3. Apparatus according to claim 2, further comprising an outer mould tool extending around an exterior of the collapsible core mould tool, wherein the outer mould tool and the collapsible core mould tool are movable relative to each other between at least a first relative position in which the outer mould tool is positioned generally in register with the first mould tool surface region, and a second relative position in which the outer mould tool is positioned generally in register with the second mould tool surface region.

4. Apparatus according to claim 3, further comprising a mover assembly for moving the collapsible core mould tool and the outer mould tool relative to each other, and wherein the mover assembly is operative to transition the collapsible core mould tool between the expanded configuration and the collapsed configuration.

5. Apparatus according to claim 3 or 4, wherein the outer mould tool is part of the transfer device.

6. Apparatus according to claim 5, further comprising a retainer for retaining a portion moulded in the first mould cavity to move with the outer mould tool.

7. Apparatus according to claim 6, wherein the retainer comprises one or more radially inwardly facing projections of the outer mould tool.

8. Apparatus according to claim 7, wherein the one or more radially inwardly facing projections are dimensioned so as to be able to pass over the surface of the collapsible core mould tool when in the expanded configuration, when the outer mould tool transitions between the first and second relative positions.

9. Apparatus according to claim 2 or any claim dependent thereon, wherein the first mould cavity is defined substantially by a combination of the outer mould tool when in the first relative position, and the collapsible core mould tool when in the expanded configuration.

10. Apparatus according to any preceding claim, operable to mould a respective article portion in each of the first and second mould cavities either substantially concurrently or during the same mould cycle.

11. Apparatus according to any preceding claim, wherein the first and second mould tool surface regions are different from each other, for moulding different article portions.

12. Apparatus according to any preceding claim, wherein the collapsible core mould tool is collapsible generally about an axis, and wherein the first and second mould tool surface regions are offset from each other in an axial direction.

13. Apparatus according to any preceding claim, wherein the second mould cavity is larger than the first mould cavity.

14. Apparatus according to any preceding claim, wherein the first mould cavity is configured for moulding a first portion of an article, and wherein the second mould cavity is configured for over-moulding a second portion of an article on a first portion previously moulded in the first cavity.

15. Apparatus according to claim 14, wherein the first portion is radially outside the second portion.

16. Apparatus according to claim 14 or 15, wherein the first and second portions are first and second components of a multi-component container closure article, moulded in assembled relation.

17. Apparatus according to any preceding claim, wherein the first mould cavity is generally annular in shape.

18. Apparatus according to any claim preceding claim, wherein the second mould cavity is generally cup-shaped.

19. Apparatus according to any preceding claim, wherein the collapsible core mould tool further comprises a partition wall projection between the first and second mould tool surface regions.

20. Apparatus for moulding a plastics container closure article, comprising: a collapsible core mould tool having a first mould tool surface region and a second mould tool surface region offset from one another in an axial direction of the collapsible core mould tool, the collapsible core mould tool being transformable between an expanded configuration presenting the mould tool surface regions for a moulding operation, and a collapsed configuration having a smaller outer periphery than the expanded configuration; a transfer device for transferring an article or component from the first mould tool surface region to the second mould tool surface region, the transfer device comprising an outer mould tool extending around an exterior of the collapsible core mould tool, wherein the outer mould tool and the collapsible core mould tool are movable relative to each other between at least a first relative position in which the outer mould tool is positioned generally in register with the first mould tool surface region, and a second relative position in which the outer mould tool is positioned generally in register with the second mould tool surface region.

21. Apparatus according to claim 20, wherein the outer mould tool comprises a at least one radially inwardly facing projection for retaining a moulded article or component to move with the outer mould tool, when the collapsible core mould tool transitions to its collapsed configuration and the outer mould tool transitions from the first relative position to the second relative position and; and wherein the collapsible core mould tool comprises a partition wall projection disposed between the first and second mould tool surface regions for retaining the moulded article or component at the second mould tool surface region when the collapsible core mould tool returns to its expanded configuration, and the outer mould tool returns to the first relative position.

22. Apparatus according to claim 21, wherein the at least one radially inwardly facing projection is dimensioned so as to be able to pass over the surface of the collapsible core mould tool when in the expanded configuration, when the outer mould tool transitions between the first and second relative positions.

23. A method of moulding a plastics container closure article, comprising the steps of: moulding a first portion of the article in a first mould cavity defined around a first mould tool surface region of a collapsible core mould tool; and moulding a second portion of the article in a second mould cavity defined around a second mould tool surface region of the same collapsible core mould tool.

24. A method according to claim 23, wherein the step of moulding the second portion of the article comprises over-moulding the second portion on an article first portion that has been moulded in the first mould cavity.

25. A method according to claim 23 or 24, further comprising the step of transferring to the second mould cavity an article first portion after moulding in the first mould cavity.

26. A method according to any of claims 23 to 25, further comprising the step of transferring to the second mould tool surface region an article first portion after moulding at the first mould tool surface region.

27. A method according to claim 25 or 26, further comprising the step of transitioning the collapsible core mould tool from an expanded configuration to a collapsed configuration, and wherein the step of transferring is performed while in the collapsed configuration.

28. A method according to claim 27, further comprising transitioning the collapsible core mould tool from the collapsed configuration to the expanded configuration for moulding the first and second portions.

29. A method according to any of claims 23 to 28, comprising moulding substantially concurrently, or during the same mould cycle, a first portion for a first article and a second portion for a second article.

30. A method of moulding a plastics container closure article and/or a method of operation of a moulding apparatus for moulding a plastics container closure article, comprising the steps of: moulding, in a first mould cycle, a first portion of the article in a first mould cavity defined around a first mould tool surface region of a collapsible core mould tool while the collapsible core mould tool is in an expanded configuration; transitioning the collapsible core mould tool to a collapsed configuration; transferring the first portion from the first mould tool surface region to a second mould tool surface region of the same collapsible core mould tool; transitioning the collapsible core mould tool to the expanded configuration; over-moulding, in a second mould cycle, and in a second mould cavity defined around the second mould tool surface region, a second portion of the article with respect to the first portion; and transitioning the collapsible core mould tool surface region to the collapsed configuration for discharging the article from collapsible core mould tool.

31. A method according to claim 30, further comprising, during the second moulding cycle, moulding a first portion of a subsequent article in the first mould cavity.

32. A method of moulding plastics container closure articles, and/or a method of operation of an apparatus for moulding plastics container closure articles, comprising the steps of: during a mould cycle, moulding in first and second cavities defined around first and second mould tool surface regions of the same collapsible core mould tool, first and second portions of respective articles; and between mould cycles: transitioning the collapsible core mould tool to a collapsed configuration; discharging a moulded article from the second mould tool surface region; transferring a moulded first portion from the first mould tool surface region to the second mould tool surface region; and transitioning the collapsible core mould tool to an expanded configuration.

33. A method according to any of claims 30 to 32, wherein the collapsible core mould tool is collapsible generally about an axis, the first and second mould tool surface regions are offset axially from each other, and wherein the step of transferring comprises transferring a first portion axially from the first mould tool surface region to the second mould tool surface region.

34. A method according to any of claims 23 to 33, wherein the first and second portions are first and second components of a multi-component article, and wherein the step of moulding the second portion comprises moulding the second portion in assembled relation with the first portion.

35. Apparatus for moulding a plastics container closure article, the apparatus configured to operate according to a method according to any of claims 31 to 34.

36. Apparatus substantially as hereinbefore described with reference to any of the accompanying drawings.

37. A method substantially as hereinbefore described with reference to any of the accompanying drawings.