JP2008155395A - Method and apparatus for molding laminated molding - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To reduce costs by simplifying the structure of a molding apparatus and to improve moldability by eliminating resin leakage in a molding method for a laminated molding formed by successively laminating a resin molding of the first layer and a resin molding of the second layer, and the molding apparatus for the laminated molding. <P>SOLUTION: In the method for molding the laminated molding, in a mold clamped state with the clearance between a movable mold 50 and a fixed mold 60 narrowed, a molten resin M1 is injected from a first injection machine 70 into a first cavity C1 to form a resin core 21 while the gate 64 of the second layer is blocked by a cavity insert 80 for gate opening/closing which is set in the movable mold 50. Next, the movable mold 50 is made to retreat in the mold opening direction, and the gate 64 of the second layer is opened by making the cavity insert 80 retreat. By injecting a molten resin M2 from a second injection machine 71 into second cavity C2 between a resin core 21 and the mold surface of the movable mold 50, a skin 22 is laminated/integrated on/with the surface of the resin core 21. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a method for molding a laminated molded article formed by adjusting the mold clearance between a movable mold and a fixed mold in two stages and performing injection filling with a molten resin in two stages, and TECHNICAL FIELD The present invention relates to a molding method and a molding apparatus for a laminated molded product that is free from resin leakage at the time of molding and can simplify a mold structure.

  FIG. 10 is a front view of the door trim, and FIG. 11 is a sectional view of the door trim. The door trim 1 is molded into a required shape, and is formed on the surface of the resin core material 2 having shape retention and mounting rigidity to the door panel. The outer skin 3 having excellent surface feel and surface appearance is laminated and integrated. The resin core material 2 is molded into a required shape by injection molding or mold press molding of a hard resin material such as polypropylene resin mixed with polypropylene resin or filler. On the other hand, as the skin 3, a synthetic resin sheet such as a vinyl chloride sheet or a TPO (thermoplastic olefin) sheet, or a laminated sheet material made of a synthetic resin sheet backed with a cushion layer such as polyurethane foam or polyolefin resin foam is used. The skin 3 is integrated when the resin core material 2 is molded.

  Next, an outline of a method for manufacturing the door trim 1 will be described. For molding the door trim 1, for example, a molding device 4 shown in FIG. 12 is used. The molding apparatus 4 is generally composed of a movable molding upper mold 5, a fixed molding lower mold 6, and two injection machines 7 a and 7 b provided continuously to the molding lower mold 6. More specifically, the molding upper die 5 can be moved up and down by a predetermined stroke by driving the press machine 5a, and the molten resin M1 is supplied from the first injection machine 7a to the mold surface of the molding lower die 6 to obtain a resin core. The material 2 is molded into a required shape, and a hot runner 6a and a gate 6b at that time are provided in the molded lower mold 6. On the other hand, in order to mold the outer skin 3, the molten resin M2 passes through the hot runners 6c and 6d (encoded as the fixed hot runner 6c and the movable hot runner 6d) and the movable gate 6e from the second injection machine 7b. Supplied.

  That is, the mold upper mold 5 is lowered to a position where the mold clearance between the mold upper mold 5 and the mold lower mold 6 corresponds to the thickness of the resin core material 2 to form the cavity C1, as shown in FIG. The molten resin M1 is injected and filled into the cavity C1 through the hot runner 6a and the gate 6b from the first injection machine 7a, and the resin core material 2 is formed into a required shape. At this time, the movable gate 6e for supplying the molten resin M2 of the second layer is positioned upward due to the extension operation of the cylinder 8, and the hot runners 6c and 6d do not coincide with each other. The resin supply is stopped.

  Next, after the resin core material 2 is molded, the molding upper die 5 rises by a predetermined stroke, and a second cavity C2 is formed between the resin core material 2 and the mold surface of the molding upper die 5, and FIG. As shown, the molten resin M2 that is the material of the skin 3 is supplied from the second injector 7b into the second cavity C2. At this time, since the cylinder 8 is contracted, the resin passages of the hot runners 6 c and 6 d coincide with each other, the molten resin M 2 is supplied into the cavity C 2 through the movable gate 6 e, and the skin 3 is laminated on the surface of the resin core material 2. Integrated. The configuration of the molding device 4 and the conventional molding method of the door trim 1 using the molding device 4 are described in detail in Patent Document 1.

JP-A-10-180782

  As described above, in the conventional molding method for molding the door trim 1 which is a laminated molded product of the resin core material 2 and the skin 3, the mold clearance between the molding upper and lower molds 5 and 6 is set narrow, and the first cavity C1 is defined, and the resin core material 2 is molded into a required shape by injecting and filling the molten resin M1 that is the material of the resin core material 2 into the first cavity C1 from the first injection machine 7a. Then, the molding upper mold 5 is moved backward in the mold opening direction to form the second cavity C2 between the resin core material 2 and the mold surface of the molding upper mold 5, and the molten resin is fed from the second injection machine 7b. M2 is injected and filled, and the skin 3 is formed integrally with the resin core 2. Therefore, at the time of injection filling of the first layer of molten resin M1, the movable gate 6e is raised and abutted against the mold surface of the molding upper mold 5, thereby sealing the movable gate 6e and the second-layer resin molding. When the skin 3 is molded as a product, the movable gate 6e is lowered to the mold surface position of the molding lower mold 6 by the contraction operation of the cylinder 8, and the molten resin M2 is moved into the second cavity C2 through the movable gate 6e. Will be injection filled.

  Therefore, in the conventional method, the structure is complicated because the movable gate 6e is pressed against the mold surface of the molding upper mold 5 by the cylinder 8 so that the resin does not enter when the resin core material 2 is molded. This is a major factor in the rise in mold costs. Further, when the resin passages are joined by the hot runners 6c and 6d, resin leakage is likely to occur, and molding defects such as material loss and short shot due to resin leakage are expected.

  The present invention has been made in view of such circumstances, and the first resin molding is performed by injecting and filling molten resin into a cavity defined between the movable mold and the fixed mold. After that, the movable mold is moved backward in the mold opening direction to form a second cavity between the first-layer resin molded article and the mold surface of the movable mold. Simplifying the mold structure in a molding method and molding apparatus for a laminated molded product in which the second resin molded product is injection-filled into the second cavity and laminated and integrated with the first resin molded product. Accordingly, it is an object of the present invention to provide a molding method and a molding apparatus for a laminated molded product with improved moldability by reducing costs and preventing short shots and material loss caused by resin leakage.

  In order to solve the above-mentioned problems, the present invention, after molding the first resin molded product by injection filling molten resin into a cavity defined between the movable side mold and the fixed side mold, In a molding method of a laminated molded product in which the movable side mold is retracted in the mold opening direction, a molten resin is injected and filled into a newly formed cavity, and a second layer of the resin molded product is laminated. The mold is lowered to the bottom dead center, and the gate of the second layer is closed by the gate opening / closing insert provided in the movable mold, and the molten resin is injected and filled into the first cavity from the first injection machine. The molding process of the first-layer resin molded product for molding the first-layer resin molded product, and the movable-side mold is moved backward in the mold opening direction to form the first-layer resin molded product and the mold surface of the movable-side mold. A second cavity is formed between them and the gate opening / closing insert is retracted from the gate. The gate is opened, molten resin is injected and filled from the second injection machine into the second cavity through the gate, and the second-layer resin molded product is laminated and integrated with the first-layer resin molded product. It consists of a molding process of a second-layer resin molded product.

  Furthermore, in a preferred embodiment of the method of the present invention, in the molding step of the first-layer resin molded product, a gap between the gate opening / closing insert and the inner wall surface of the concave portion of the fixed mold is sealed by a shear structure. By doing so, the gate of the second layer is blocked.

  Here, the application target of the laminated molded product includes automotive interior parts in general, for example, door trim, rear parcel shelf, floor trim, trunk trim, luggage side trim, roof trim, rear side trim and the like. Also, the first-layer resin molded product has a function as a hard base core material, and the second-layer resin molded product laminated on the surface has a surface feel and excellent skin function. preferable. As materials for the first-layer resin molded product and the second-layer resin molded product, the materials of the first-layer resin molded product suitable for the base core material are polyethylene resin, polypropylene resin, polystyrene resin, polyethylene Terephthalate resin, polyvinyl alcohol resin, vinyl chloride resin, polyamide resin, polyacetal resin, polycarbonate resin, ionomer resin, acrylonitrile / butadiene / styrene (ABS) resin, etc. can be used. You may comprise the filler which used as raw materials inorganic particles, such as fillers, for example, inorganic fibers, such as glass fiber and carbon fiber, and talc, clay, silica, and calcium carbonate.

  On the other hand, as the material of the second-layer resin molded article suitable for the skin, a soft resin material, for example, a soft vinyl chloride resin, a thermoplastic elastomer resin, a synthetic rubber material such as EPDM, or a foamable resin material is used. Is possible.

  In addition, as a molding apparatus used for the molding method, a first-layer resin molded product is molded by injecting and filling molten resin into a cavity defined between a movable mold and a fixed mold. , A revolving operation of the movable mold in the mold opening direction, injection molding of a molten resin into a newly formed cavity, and a laminated molded product formed by laminating a second resin molded product. In the molding apparatus, the molding apparatus includes a movable mold and a fixed mold that can be opened and closed with each other, and the movable mold is for opening and closing a gate that can be advanced and retracted into a cavity by driving a cylinder. When the nest is provided and the first-layer resin molded product is molded, the gate of the second layer is closed with the above-mentioned nest for opening and closing the gate.

  Therefore, the method of the present invention generally comprises a molding step for the first-layer resin molded product and a molding step for the second-layer resin molded product integrated on the surface side of the first-layer resin molded product. . In the molding process of the first-layer resin molded product, the movable side mold is moved in the mold clamping direction, the mold clearance between the movable side mold and the fixed side mold is kept narrow, and the first cavity is defined. The molten resin is injected and filled into the first cavity, and the first-layer resin molded product is molded into the required shape. At this time, the gate opening / closing insert provided in the movable mold is fixed. The second layer gate provided in the side mold is closed, and the molten resin, which is the material of the first layer resin molded product, flows so as to avoid the gate opening / closing insertion.

  Next, after the first-layer resin molded product is molded, the movable mold is moved backward in the mold opening direction so that the second cavity is formed between the first-layer resin molded product and the mold surface of the movable mold. Form. Then, the molten resin is injected and filled into the second cavity, and the second-layer resin molded product can be integrated with the surface side of the first-layer resin molded product. At this time, the gate opening / closing nest provided in the movable mold is detached from the second-layer gate by driving the cylinder and is accommodated in the movable mold. Is injected and filled into the second cavity through the resin passage, so that the second-layer resin molded product can be accurately integrated with the surface side of the first-layer resin molded product.

  Therefore, according to the method of the present invention, when the gate opening / closing insert for driving the cylinder is attached to the movable mold, and the first layer resin is injected and filled, the gate of the second layer is inserted by the gate opening / closing insert. As long as it can be closed, it is possible to cope with a simple mold structure in which a cylinder driven nest is provided in the movable mold, and therefore the cost can be reduced by simplifying the structure of the molding apparatus.

  In addition, since the hot runner is not provided in a joint type as in the prior art, no resin leakage occurs and short shots can be prevented and material loss can be prevented. Furthermore, in the past, it has been pointed out that pressing the movable gate against the mold damages the drawing pattern of the mold and impairs the appearance performance. Since the seal is sealed with a shear structure, the squeezed pattern of the insert is not damaged, and a good product appearance can be obtained.

  As described above, according to the molding method and molding apparatus for a laminated molded product according to the present invention, the mold clearance between the movable mold and the fixed mold is narrowed to define the first cavity, and the two layers The first resin molded product is molded into the required shape by injecting and filling molten resin into the first cavity with the gate opening / closing insert provided in the movable mold on the gate of the eye. After that, the movable side mold is retracted in the mold opening direction, and the gate opening / closing insert is detached from the second layer gate, so that the first-layer resin molded product and the mold surface of the movable side mold are separated. The second layer resin molded product is laminated and integrated by injecting and filling molten resin into the second cavity formed in the cylinder, so the cylinder type gate opening and closing that covers the second layer gate A simple structure in which the insert is installed on the movable mold Rukoto can, conventional movable gate structure, compared with the joint-type hot runner structure or the like, has the effect that expected a significant cost reduction due to simplified structure.

  Furthermore, according to the molding method and molding apparatus of the laminated molded product according to the present invention, resin leakage or the like due to the joint hot runner does not occur, so that short shots and material loss can be prevented and molding performance can be improved. In addition to being sealed by the shear action between the nesting and the fixed mold, the squeezing pattern of the nesting is not damaged, and the appearance design is improved by faithfully displaying the squeezing pattern. It has the effect that it can be kept good.

  Hereinafter, preferred embodiments of a method and apparatus for molding a laminated molded product according to the present invention will be described by exemplifying a molding method for a two-tone type automobile door trim and a molding apparatus used for the method. Note that the gist of the present invention is as described in the scope of claims, and the contents of the embodiments described below are merely examples of the present invention.

  1 to 9 show an embodiment of the present invention, FIG. 1 is a front view showing a two-tone type automobile door trim, FIG. 2 is a sectional view showing the structure of the door trim, and FIG. 3 is a view of a door trim upper in the door trim. 4 and 5 show an example of a molding apparatus for a laminated molded product according to the present invention, FIG. 4 is an overall view, FIG. 5 is a plan view of a fixed mold in the molding apparatus, and FIGS. 9 is an explanatory view of each process showing a method of forming the door trim.

  1 to 3, a two-tone type automobile door trim 10 is composed of an upper and lower divided body of a door trim upper 20 and a door trim lower 30. As shown in FIG. 1, an inside handle is provided on the product surface side. An escutcheon 11 is attached. Further, an armrest 12 is formed on the surface of the door trim 10 so as to bulge out toward the passenger compartment side, and an occupant rests on an elbow, and a switch containing a switch element such as a power window switch is provided on the upper surface of the armrest 12. An escutcheon panel 13 and a pull handle unit 14 are attached. Furthermore, a door pocket opening 15 capable of accommodating equipment is opened on the lower side of the armrest 12, and a pocket back cover 16 is attached to the back side of the door pocket opening 15 as shown in FIG. A speaker grill 17 is formed integrally with the door trim 10 or separately from the front side of the door pocket opening 15.

  More specifically, the door trim upper 20 is constituted by a two-layer laminated product in which the skin 22 is laminated on the surface of the resin core material 21, while the door trim lower 30 is constituted by a single product of synthetic resin. Next, in the joining structure of the door trim upper 20 and the door trim lower 30, a mounting boss 31 is erected on the rear surface of the upper edge side of the door trim lower 30, and a mounting hole 23 is formed in the door trim upper 20 so as to correspond to it. Has been. Then, after the mounting boss 31 is inserted into the mounting hole 23, the front end of the mounting boss 31 is crimped by ultrasonic welding or thermal welding, so that the door trim upper 20 and the door trim lower 30 are firmly attached. It is fixed.

  Moreover, as shown in FIG. 3, the shape of both side edges of the resin core 21 and the skin 22 in the door trim upper 20 is set as an inclined flange 20a. This is required to be set to such a shape when a molding method of the door trim upper 20 described later is carried out. In the present invention, the resin core material 21 and the skin 22 are integrally formed by using an injection molding method. As the material of the resin core material 21, polyethylene resin, polypropylene resin, polystyrene resin, polyethylene terephthalate are used. Resin, polyvinyl alcohol resin, vinyl chloride resin, polyamide resin, polyacetal resin, polycarbonate resin, ionomer resin, acrylonitrile / butadiene / styrene (ABS) resin, and the like can be used. As the material of the skin 22, a soft resin material such as a soft vinyl chloride resin, a thermoplastic elastomer resin, a synthetic rubber material such as EPDM, or a foamable resin material can be used.

  By the way, the present invention simplifies the structure of the molding device 40 when molding the door trim upper 20 that is a two-layer laminate, thereby reducing costs and preventing resin leakage and short shots from occurring. Thus, the door trim upper 20 can be molded with improved moldability and excellent design.

  4 and 5, the general configuration of the molding apparatus 40 will be described. The molding apparatus 40 supplies a movable mold 50 located on the product surface side of the door trim upper 20, a fixed mold 60 located on the back side of the resin core material 21, and materials for the resin core material 21 and the skin 22. The two injection machines 70 and 71 and the gate opening / closing insert 80 provided in the movable mold 50 and capable of opening and closing the gate of the second layer are roughly configured.

  More specifically, the movable side mold 50 is configured to be movable up and down by a predetermined stroke by an elevating cylinder 51, and the fixed side mold 60 has a resin passage for molten resin from two injection machines 70 and 71. As shown, a hot runner 61 and a gate 62 serving as a material passage for the first-layer resin molded product (resin core material 21) are provided, and a material passage for the second-layer resin molded product (skin 22) is provided. A hot runner 63 and a gate 64 are provided. In particular, in the vicinity of the gate 64 of the second layer, a gate opening / closing insert 80 and a recess 65 capable of sealing the gate 64 by a shearing action are provided in an annular shape. The gate opening / closing insert 80 has a function of opening and closing the second-layer gate 64 by operating in the direction of the arrow in FIG.

  Next, a method for forming the door trim upper 20 will be described with reference to FIGS. First, as shown in FIG. 6, the movable mold 50 is lowered to the bottom dead center by driving the lifting cylinder 51, and the mold clearance between the movable mold 50 and the fixed mold 60 is a resin core. Both molds 50 and 60 are clamped until they correspond to the thickness of the material 21, and a first cavity C1 is defined. At this time, the gate opening / closing insert 80 protrudes downward due to the expansion action of the cylinder 81, and the inner wall surface of the peripheral recess 65 of the second-layer gate 64 in the fixed mold 60 and the gate opening / closing insert 80. Is sealed by the shearing action.

  Further, in this state, the molten resin M1, which is the material of the resin core material 21, is injected and filled into the first cavity C1 through the hot runner 61 and the gate 62 from the first injection machine 70, so that the resin core material 21 has the required shape. To be molded. In the injection filling process of the molten resin M1, the gate opening / closing insert 80 is sealed by the shearing action with the inner wall surface of the recess 65 in the vicinity of the second-layer gate 64, as shown in FIG. The resin leakage of M1 can be prevented as much as possible, and the drawn pattern 80a of the gate opening / closing insert 80 is not damaged.

  Then, after the resin core material 21 as the first-layer resin molded product is formed into a required shape, the movable side mold 50 is retracted in the mold opening direction as shown in FIGS. 21 and the mold surface of the movable mold 50 are formed, and the cylinder 81 of the gate opening / closing insert 80 is contracted to raise the gate opening / closing insert 80. Thus, it is flush with the mold surface of the movable mold 50. In this state, the soft resin M2 that is the material of the skin 22 is injected and filled into the second cavity C2 through the hot runner 63 and the gate 64 from the second injector 71, and the surface of the resin core 21 is obtained. By integrating the skin 22 on the side, the door trim upper 20 is accurately molded.

  As described above, in the method of the present invention, the door trim upper 20 that is a laminated molded product of the resin core material 21 and the skin 22 can be easily and inexpensively provided with a simple structure in which the movable opening die 50 is provided with the gate opening / closing insert 80. Therefore, by simplifying the structure of the molding device 40, a significant cost reduction can be expected, and since the movable gate structure and joint type hot runner structure are eliminated as in the past, there is no resin leakage. There is also an effect that short shots and material loss can be prevented in advance. In addition, since the gate opening / closing insert 80 is not configured to abut against the mold surface, the drawn pattern 80a provided on the lower surface of the gate opening / closing insert 80 is not damaged, so that a good appearance performance can be obtained for a long time. Can be maintained for a long time.

  In the embodiment, the method of the present invention is applied to the door trim upper 20 in the upper and lower split type door trim 10, but if it is a two-layer laminated product consisting of a resin core material 21 as a base and a soft skin 22, Not only door trims, but can be applied to all automotive interior parts such as rear parcel shelf, floor trim, trunk trim, luggage side trim, roof trim, and rear side trim.

  The method of the present invention employs an injection molding method in which the molds are clamped to form cavities and then the molten resins M1 and M2 are injected and filled into the cavities C1 and C2. A mold press molding method in which M2 is injected and filled can also be used.

It is a front view which shows the door trim for motor vehicles of the upper and lower divided type produced using the shaping | molding method of the laminated molded product which concerns on this invention. It is the II-II sectional view taken on the line in FIG. FIG. 3 is a sectional view taken along line III-III in FIG. 1. It is explanatory drawing which shows the whole structure of the shaping | molding apparatus used for shaping | molding the door trim upper in the door trim shown in FIG. It is a top view which shows the die surface shape of the stationary side metal mold | die in the shaping | molding apparatus shown in FIG. It is explanatory drawing which shows the molding process of the 1st resin molded product in the molding method of the door trim upper which uses the molding apparatus shown in FIG. It is explanatory drawing which shows the structure of the gate vicinity of the 2nd layer in the formation process of the resin molded product of the 1st layer shown in FIG. It is explanatory drawing which shows the shaping | molding process of the resin molded product of the 2nd layer in the shaping | molding method of the door trim upper which uses the shaping | molding apparatus shown in FIG. It is explanatory drawing which shows the structure of the gate vicinity of the 2nd layer in the shaping | molding process of the skin shown in FIG. It is a front view which shows the conventional door trim. It is the XI-XI sectional view taken on the line in FIG. It is explanatory drawing which shows the whole structure of the shaping | molding apparatus of the conventional 2 layer molded product. It is explanatory drawing which shows the shaping | molding process of the resin molded product of the 1st layer in the shaping | molding method of the conventional 2 layer molded product. It is explanatory drawing which shows the manufacturing method of the resin molded product of the 2nd layer in the shaping | molding method of the conventional 2 layer molded product.

Explanation of symbols

10 Door Trim 20 Door Trim Upper 21 Resin Core Material (First-layer Plastic Molded Product)
22 Skin (second layer resin molded product)
DESCRIPTION OF SYMBOLS 23 Mounting hole 30 Door trim lower 31 Mounting boss 40 Molding device 50 Movable side mold 51 Lifting cylinder 60 Fixed side mold 61,63 Hot runner 62,64 Gate 65 Recessed part 70 First injection machine 71 Second injection machine 80 Nest for gate opening / closing 80a Drawing pattern 81 Cylinder C1 First cavity C2 Second cavity M1 Molten resin (for first-layer resin molded product)
M2 molten resin (for second-layer resin molded products)

Claims (3)

A molten resin (M1) is injected and filled into a cavity (C1) defined between the movable mold (50) and the fixed mold (60) to form a first-layer resin molded article (21). After that, the movable mold (50) is retracted in the mold opening direction, and the newly formed cavity (C2) is injected and filled with the molten resin (M2) to obtain the second-layer resin molded product (22). In the molding method of the laminated molded product (20) formed by lamination,
The movable die (50) is lowered to the bottom dead center, and the gate (64) of the second layer is closed by the gate opening / closing insert (80) provided in the movable die (50), so that the first cavity (C1) injection molding of the molten resin (M1) from the first injection machine (70) to mold the first-layer resin molded product (21); ,
The movable side mold (50) is moved backward in the mold opening direction to form the second cavity (C2) between the first-layer resin molded product (21) and the mold surface of the movable side mold (50). At the same time, the gate opening / closing insert (80) is retracted from the gate (64), the gate (64) is opened, and the molten resin from the second injection machine (71) enters the second cavity (C2). (M2) is injected and filled through the gate (64), and the second-layer resin molded product (22) in which the second-layer resin molded product (22) is laminated and integrated with the first-layer resin molded product (21). Molding process,
A method for forming a laminated molded product comprising:   In the molding process of the first-layer resin molded product (21), the gap between the gate opening / closing insert (80) and the inner wall surface of the concave portion (65) of the fixed mold (60) is sealed by a shear structure. The method for molding a laminated molded product according to claim 1, wherein the gate (64) of the second layer is closed. A molten resin (M1) is injected and filled into a cavity (C1) defined between the movable mold (50) and the fixed mold (60) to form a first-layer resin molded article (21). After that, the movable mold (50) is retracted in the mold opening direction, and the newly formed cavity (C2) is injected and filled with the molten resin (M2) to obtain the second-layer resin molded product (22). In the molding apparatus (40) of the laminated molded product (20) for molding the laminated molded product (20) formed by lamination,
The molding device (40) includes a movable side mold (50) and a fixed side mold (60) that can be mutually opened and clamped. The movable side mold (50) includes a cylinder (81). When a gate opening / closing insert (80) that can be advanced and retracted in the cavity (C1, C2) by driving is provided and the first-layer resin molded product (21) is molded, the second-layer gate (64) is connected to the above-mentioned An apparatus for forming a laminated molded product, which is closed by a gate opening / closing insert (80).

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