INJECTION MOLDING SYSTEM

An injection molding system includes an injection unit that injects resin into a mold and a coupling member that couples a fixed mold plate and a movable mold plate of the mold, wherein an improvement to the injection molding system includes a driving member that separates the fixed mold plate from a fixed platen by moving the movable mold plate when the fixed mold plate and the movable mold plate are coupled by the coupling member.

FIELD

The disclosure herein relates to an injection molding system for manufacturing plastic parts.

BACKGROUND

Manufacturing of molded parts by an injection molding machine includes clamping a mold, injecting a resin into a mold, pressing the resin into the mold at a high pressure in order to compensate for a volume decrease due to solidification of the resin, keeping the molded part in the mold until the resin solidifies, and removing the molded part from the mold. The injection molding process is repeatedly performed to obtain a desired number of molded parts. After a predetermined number of moldings are performed with one mold, the mold is ejected from the injection molding machine, the next mold is setup and inserted into the injection molding machine. A predetermined number of injection moldings with the next mold is then performed.

The above process can take time and resources, and typically the injection molding machine remains in a waiting condition during the process. This can affect overall productivity. Since the mold is heavy and becomes heated during use, it is necessary to consider the safety of the operator.

In the above-described molding approach, a method using two molds with one injection molding machine has been proposed. For example, US 2018/0009146/Japanese patent publication No. 2018-001738/VN20160002505 are seen to discuss a system in which conveying machines are arranged on both sides of an injection molding machine. In this system, molded parts are manufactured while alternating a plurality of molds by conveying devices for the one injection molding machine.

The injection molding system of US 2018/0009146/Japanese patent publication No. 2018-001738/VN20160002505, includes spring rollers that are embedded in inner surfaces of a fixed platen and a movable platen of the injection molding machine. The spring rollers enable separating the fixed platen surface from a mold mounting surface when a mold is conveyed out of the injection molding machine and a guiding function when the mold is conveyed in/out of the injection molding machine. To achieve this, grooves for embedding the spring rollers in the platens of the injection molding machine and to arrange a plurality of spring rollers were created, which impacts cost for the injection molding system.

What is needed is an injection molding system that enables separating of platens in a more efficient manner.

SUMMARY

An exemplary aspect of the present disclosure includes an injection molding system comprising an injection unit for injecting resin into a mold, a coupling member for coupling a fixed mold plate and a movable mold plate of the mold, and a driving member for separating the fixed mold plate from the fixed platen by moving the movable mold plate in a state where the fixed mold plate and the movable mold plate are coupled by the coupling member.

DESCRIPTION OF THE EMBODIMENTS

The present disclosure has several embodiments and relies on patents, patent applications and other references for details known to those of the art. Therefore, when a patent, patent application, or other reference is cited or repeated herein, it should be understood that it is incorporated by reference in its entirety for all purposes as well as for the proposition that is recited.

With reference to the drawings, an injection molding system according to an embodiment of the present disclosure will be described. The arrow symbols X and Y in each Figure indicate horizontal directions that are orthogonal to each other, and the arrow symbol Z indicates a vertical (perpendicular) direction.

FIG.1illustrates a view of an injection molding system1of an exemplary embodiment viewed from a Z-axis direction.FIG.2illustrates a view of the injection molding system1viewed from an X-axis direction.FIG.5illustrates a flow chart describing the operation of the injection molding system1. Each of the steps illustrated inFIG.5is realized by a processor (not illustrated) of the injection molding system1reading and executing a program stored in a memory (not illustrated).

The injection molding system1comprises a horizontal injection unit5including an injection nozzle2, an injection cylinder3, and a hopper4. The injection unit injects a resin into a mold. A mold conveying device8, that alternately conveys a mold6and a mold7into and out of an injection position, is installed on both sides of the injection position in the X-axis direction. The injection position is a position suitable for injection processing by the injection unit5. The mold conveying device8is equipped with a driving source (not illustrated), a linking member9, and a guide roller10for guiding conveyance of the mold6and the mold7. WhileFIG.1illustrates these elements in the top portion ofFIG.1, the bottom portion is a mirror image and the same reference numbers are applicable.

The injection molding system1also comprises a fixed bottom surface roller11and a movable bottom surface roller12for supporting a mold via the bottom surface when the mold is conveyed to the injection position. A fixed platen13, a movable platen14, and a mold clamping force generating device15are also part of the injection molding system1. Mold6and mold7both comprise a fixed clamping plate16, a fixed mold plate17, a movable clamping plate18, a movable mold plate19, and a magnetic lock20that is provided at the boundary between the fixed mold plate17and the movable mold plate19. WhileFIG.1illustrates these elements with respect to mold6, they are applicable to mold7as well.

FIG.3illustrates a view of the fixed platen of the present embodiment viewed from a Y-axis direction. The fixed bottom surface roller11is arranged between a fixed mold clamp21and a tie bar22to perform a guide function when conveying a mold. A location ring hole23is opened on the fixed side. (Please note that reference number23is used below for other elements. Please update the reference number for those elements such that reference number23is not reused. Please ensure that any changes made to the Specification are also reflected in the appropriate corresponding Figure(s))

FIGS.4A-4Iillustrate a mold opening/closing operation flow of the present embodiment. More specifically,FIGS.4A-4Iillustrate states from when a mold is conveyed into the injection position to when a molded part is removed, injection filled, and the mold conveyed out of the injection position.

FIG.4Aillustrates a state when a mold is conveyed into the injection position.FIG.4Billustrates a closed state of the mold where the movable platen14is closed.FIG.4Cillustrates a state where the fixed mold clamp21and the movable mold clamp24are simultaneously clamped.FIG.4Dillustrates a state where the movable platen14is opened and the molded part removed.FIG.4Eillustrates a state where the movable platen14is closed and resin injected and filled.FIG.4Fillustrates a state where just the fixed mold clamp21is released after the injection filling.FIG.4Gillustrates a state where the movable platen14is slightly opened and the fixed clamping plate16and the fixed platen13of the mold are separated.FIG.4Hillustrates a state where the movable mold clamp24is released.FIG.4Iillustrates a state where the movable platen14is again slightly opened and the movable platen14and the movable clamping plate18of the mold are separated.

FIG.5illustrates a flow chart of the operation of the injection molding system1of the present embodiment.

In step S101, the mold6is conveyed in the X-axis direction by the driving source (not illustrated) of the mold conveying device8and the linking member9of the mold6into the space between the fixed platen13and the movable platen14of the injection molding system1.FIG.4Aillustrates a view of the state when the mold6is conveyed into the injection position viewed from the X-axis direction.

In step S103, the mold6is clamped. Then, in step S105, the fixed mold clamp21and the movable mold clamp24are operated to fix the mold6to the fixed platen13and the movable platen14.FIG.4Cillustrates this the state.

When a cooling time of the resin that was previously injected into the mold6has elapsed, in step S107, the movable platen14is opened to remove a molded part from the mold6.FIG.4Dillustrates the state where the mold6is opened and a molded part is removed. In a case where a first molding operation is being performed, this process can be omitted because there is no molded part yet.

In step S109, melted resin in the injection cylinder3is injected into the mold6via the injection nozzle2.FIG.4Eillustrates this state.

In step S111, after the injection and dwelling processes are completed, the fixed mold clamp21is released in order to convey the mold A from the injection position.FIG.4Fillustrates the state when the fixed mold clamp21is released. At this time, the movable mold clamp24maintains a clamping force on the mold6.

The movable platen14is then slightly opened in step S113. By slightly opening the movable platen14while clamping the movable clamping plate18of the mold A, the fixed platen13and the fixed clamping plate16are separated. That is, a force for movement with respect to the movable platen14is provided in a state where coupling between the fixed clamping plate16and the movable platen14is maintained by the movable mold clamp24.FIG.4Gillustrates the state after the movable platen14is moved.

The magnet lock20provides an adhesion force stronger than a frictional force generated between the mold6and the fixed bottom surface roller11, which enables the mold6to be integrally moved without separating the fixed mold plate17and the movable mold plate19. That is, the magnet lock20functions as a coupling member for coupling the fixed mold plate17and the movable mold plate19of the mold6with a magnetic force. The fixed clamping plate16can be separated from the fixed platen13by moving the movable mold plate19with the fixed mold plate17and the movable mold plate19coupled by the magnet lock20. The magnet lock20can be fixed to any side surface of the fixed mold plate17and the movable mold plate19. In another exemplary embodiment, another fixing member such as a hydraulic jack can be provided instead of the magnet lock20.

As illustrated inFIGS.4A-4I, the moving direction of the movable mold plate19in step S113is parallel to an injection direction of the resin by the injection unit5. The moving direction of the movable mold plate19in step S113is the reverse of the moving direction of the movable mold plate19in the mold clamping process in S103.

In step S115, the movable mold clamp24is released.FIG.4Hillustrates this state.

In step S117, the movable platen14is again slightly opened, and the movable platen14and the movable clamping plate18are separated. To more reliably separate the movable platen14and the movable clamping plate18, in the present embodiment, the fixed clamping plate16hooks on an edge or flange portion of the fixed mold clamp21or the fixed bottom surface roller11. When a gap is generated between the movable platen14and the movable clamping plate18, this enables preventing the movable platen14and the movable clamping plate18from rubbing and wearing down when a mold is conveyed out of the injection position.FIG.4Iillustrates this state.

In step S119, The mold6is conveyed from the injection position, where the mold6, the fixed platen13, and the movable platen14are not in contact with each other.

After the mold6is conveyed from the injection position, steps S101-S119ofFIG.5are then performed for the mold7.

Steps S101-S119are repeated in the order of mold6, moldB7, mold6, mold7, etc. until a target production number of molded parts for each of the molds is reached.

The above-described embodiments makes is possible to separate a mold and a platen when conveying the mold from an injection position without requiring the platen to include spring rollers.

The guide function of the above-described embodiment helps to increase a conveying speed of a mold, as well as help realize a safer conveying process for a mold. This can be achieved via a flange portion on a bottom roller, and by positively abutting the mold on the flange portion of the bottom roller at the time of conveyance.

FIGS.6A-6Billustrate a view of the injection molding system1of another exemplary embodiment 2 viewed from an X-axis direction, with a focus on a platen portion and a mold portion of the injection molding system1.FIG.6Aillustrates a state when a mold is conveyed into or from a space between the fixed platen13and the movable platen14.FIG.6Billustrates a state when a mold is closed by the mold closing operation of the movable platen14.

As illustrated inFIG.6A, a fixed ball plunger25and a movable ball plunger26are embedded in the fixed clamping plate16and the movable clamping plate18of a mold, respectively. The mold is conveyed in and out of the injection position while the ball portions (not illustrated) of the fixed ball plunger25and the movable ball plunger26slide, respectively, with the fixed platen13or the movable platen14.

After the mold is conveyed into the injection position, a spring portion32, as illustrated inFIG.9, of the fixed ball plunger25and the movable ball plunger26contract by being compressed along with the mold closing operation of the movable platen14, and the fixed ball plunger25and the movable ball plunger26retract into the mold clamping plate16, so that the injection filling operation is not hindered.

As described inFIG.5, clamps on the fixed side and the movable side are not separately released. More specifically, after step S109, the fixed mold clamp21and the movable mold clamp24are simultaneously released. The movable platen14is opened, and the mold is pushed up by the force of the spring portion32of the of the fixed ball plunger25and the movable ball plunger26to separate the mold clamping plate16from the fixed platen13and the movable platen14.

While the magnet lock20functioned as a coupling member for coupling the fixed mold plate17and the movable mold plate19in the previous embodiment, in the present embodiment, the fixed mold plate17and the movable mold plate19are coupled by an elastic force provided by the spring portion32of the fixed ball plunger25and the movable ball plunger26. More specifically, the fixed mold plate17and the movable mold plate19are coupled using the elastic force of the spring portion32of the fixed ball plunger25provided between the fixed mold plate17and the fixed platen13and the elastic force of the spring portion32of the movable ball plunger26provided between the movable mold plate19and the movable platen14.

When, for example, a spring roller is embedded in a platen, it is necessary to assume a maximum mold weight to be used in the injection molding system when selecting the part. However, when embedding a ball plunger in a mold, it is sufficient to select a part suitable for the mold's weight, so that a design with a reduced cost becomes possible without generating an excessive mold push-up force. By utilizing the thickness of a clamping plate of a mold, it is possible to provide a sliding function to the mold clamping without losing the thickness of the mold.

In an exemplary embodiment, to address an issue of wear caused by sliding of a ball portion of a ball plunger and a platen, a thin plate with a degree of hardness greater than the platen can be inserted between the platen and a mold clamping plate so the mold clamping plate can be replaced based on amount of wear.

In another exemplary embodiment, to avoid loss of mold thickness, a space can be formed where a thin plate can be embedded in a platen and the thin plate can be fixed therein.

FIG.7illustrates a view of the injection molding system1of another exemplary embodiment viewed from an X-axis direction with a focus on a portion between the fixed platen13and the movable platen14of the injection molding system1. More specifically,FIG.7illustrates a state where a mold is fixed by the fixed mold clamp21and the movable mold clamp24in a space between the fixed platen13and the movable platen14. As illustrated inFIG.7, a mold is provided with a cylinder fixing part27and a cylinder28. After the fixed mold clamp21and the movable mold clamp24are released and the movable platen14is opened, the fixed platen12and the movable platen14are pushed by driving the cylinder28to separate the fixed platen13and the movable platen14from the fixed clamping plate16and movable clamping plate18. Thus, it is possible to avoid wear due to sliding of a mold and the fixed platen and the movable platen when conveying the mold.

The driving mechanism (not illustrated) of the cylinder28can be any type of driving source, such as hydraulic pressure, air, etc.

In another exemplary embodiment, to avoid the cylinder28from directly pushing on the fixed platen and the movable platen, a thin receiving plate (not illustrated) can be provided between the cylinder28and the fixed platen13and the movable platen14.

FIGS.8A and8Billustrate a view of the injection molding system1of another exemplary embodiment viewed from an X-axis direction with a focus on a platen portion and a mold portion.FIG.8Aillustrates a cylinder29embedded in the fixed clamping plate16and the movable clamping plate18respectively.FIG.8Billustrates a plate30located between the fixed clamping plate16and the fixed platen13, where the cylinder29can be embedded therein.

InFIG.8A, since the cylinder29is embedded in the fixed clamping plate16and the movable clamping plate18, the thickness of the mold is not affected. Since the cylinder29can be embedded in the fixed clamping plate16and the movable clamping plate18, and not in the fixed platen13and the movable platen14of the injection molding system1, the cylinder29can be selected based on, for example, a weight of the mold.

Based on the configuration illustrated inFIG.8A, after the fixed mold clamp21and the movable mold clamp24is released and the movable platen14is opened, the fixed platen13and the movable platen14are pushed by driving the cylinder29, resulting in the fixed platen13and the movable platen14separating from the fixed mold clamping plate16and the movable mold clamping plate18. That is, the cylinder29embedded in the fixed clamping plate16separates the fixed clamping plate16and the fixed platen13by pushing the fixed platen13. The cylinder29embedded in the movable clamping plate18separates the movable clamping plate18and the movable platen14by pushing the movable platen14. Thus, it is possible to avoid wear due to sliding of a mold and the fixed platen13and the movable platen14when conveying the mold.

The driving mechanism (not illustrated) of the cylinder28can be any type of driving source, such as hydraulic pressure, air, etc.

InFIG.8B, while the cylinder29is embedded in the fixed mount plate30between the fixed clamping plate16and the fixed platen13, the cylinder29can be embedded in the movable mount plate31between the movable clamping plate18and the movable platen14.

Based on the configuration illustrated inFIG.8B, after the fixed mold clamp21and the movable mold clamp24are released and the movable platen14is opened, the cylinder29embedded in the fixed mount plate30between the fixed clamping plate16and the fixed platen13separates the fixed clamping plate16and the fixed mount plate30by pushing the fixed clamping plate16, and the cylinder29embedded in the movable mount plate31between the movable clamping plate18and the movable platen14separates the movable clamping plate18and the movable mount plate31by pushing the movable clamping plate18. Thus, it is possible to avoid wear due to sliding of the mold and the fixed mount plate30and the movable mount plate31when conveying the mold.

Definitions

In referring to the description, specific details are set forth in order to provide a thorough understanding of the examples disclosed. In other instances, well-known methods, procedures, components and circuits have not been described in detail as not to unnecessarily lengthen the present disclosure.

It should be understood that if an element or part is referred herein as being “on”, “against”, “connected to”, or “coupled to” another element or part, then it can be directly on, against, connected or coupled to the other element or part, or intervening elements or parts may be present. In contrast, if an element is referred to as being “directly on”, “directly connected to”, or “directly coupled to” another element or part, then there are no intervening elements or parts present. When used, term “and/or”, includes any and all combinations of one or more of the associated listed items, if so provided.

Spatially relative terms, such as “under” “beneath”, “below”, “lower”, “above”, “upper”, “proximal”, “distal”, and the like, may be used herein for ease of description to describe one element or feature's relationship to another element(s) or feature(s) as illustrated in the various figures. It should be understood, however, that the spatially relative terms are intended to encompass different orientations of the device in use or operation in addition to the orientation depicted in the figures. For example, if the device in the figures is turned over, elements described as “below” or “beneath” other elements or features would then be oriented “above” the other elements or features. Thus, a relative spatial term such as “below” can encompass both an orientation of above and below. The device may be otherwise oriented (rotated 90 degrees or at other orientations) and the spatially relative descriptors used herein are to be interpreted accordingly. Similarly, the relative spatial terms “proximal” and “distal” may also be interchangeable, where applicable.

The term “about,” as used herein means, for example, within 10%, within 5%, or less. In some embodiments, the term “about” may mean within measurement error.

The terms first, second, third, etc. may be used herein to describe various elements, components, regions, parts and/or sections. It should be understood that these elements, components, regions, parts and/or sections should not be limited by these terms. These terms have been used only to distinguish one element, component, region, part, or section from another region, part, or section. Thus, a first element, component, region, part, or section discussed below could be termed a second element, component, region, part, or section without departing from the teachings herein.

The terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting. The use of the terms “a” and “an” and “the” and similar referents in the context of describing the disclosure (especially in the context of the following claims) are to be construed to cover both the singular and the plural, unless otherwise indicated herein or clearly contradicted by context. The terms “comprising,” “having,” “includes”, “including,” and “containing” are to be construed as open-ended terms (i.e., meaning “including, but not limited to,”) unless otherwise noted. Specifically, these terms, when used in the present specification, specify the presence of stated features, integers, steps, operations, elements, and/or components, but do not preclude the presence or addition of one or more other features, integers, steps, operations, elements, components, and/or groups thereof not explicitly stated. Recitation of ranges of values herein are merely intended to serve as a shorthand method of referring individually to each separate value falling within the range, unless otherwise indicated herein, and each separate value is incorporated into the specification as if it were individually recited herein. For example, if the range 10-15 is disclosed, then 11, 12, 13, and 14 are also disclosed. All methods described herein can be performed in any suitable order unless otherwise indicated herein or otherwise clearly contradicted by context. The use of any and all examples, or exemplary language (e.g., “such as”) provided herein, is intended merely to better illuminate the disclosure and does not pose a limitation on the scope of the disclosure unless otherwise claimed. No language in the specification should be construed as indicating any non-claimed element as essential to the practice of the disclosure.