WO2007052351A1

WO2007052351A1 - Multilayer injection molding apparatus, and method for producing laminated resin molded product using said multilayer injection molding apparatus

Info

Publication number: WO2007052351A1
Application number: PCT/JP2005/020234
Authority: WO
Inventors: Akio Okamoto; Hiroaki Miyoshi; Toshikazu Iwamoto; Takuya Maruyama; Kenichi Ogawa; Ryuichi Ishitsubo
Original assignee: Wako Giken Kogyo Co., Ltd.; Ube Machinery Corporation, Ltd.
Priority date: 2005-11-02
Filing date: 2005-11-02
Publication date: 2007-05-10
Also published as: JPWO2007052351A1

Abstract

This invention provides a multilayer injection molding apparatus for molding and laminating an additional layer on one layer only in its partial area, and a method for producing a laminated resin molded product using the multilayer injection molding apparatus. The multilayer injection molding apparatus is characterized in that the apparatus comprises a weir part molding region (304) for molding a flat upright face (29), which is parallel to the direction of reduction/enlargement of the volume of the cavity (300), provided on at least one site in a cavity (300) and that, in one of a plurality of injection apparatuses (231, 232), upon filling of the whole region of the cavity (300) with a thermoplastic resin followed by the enlargement of the volume of the cavity (300) to form an additional cavity, the filled resin present in the weir part molding region (304) divides the additional cavity into a plurality of spaces (400, 410), and a flow passage in communication with one of the plurality of injection apparatus is provided in each of the plurality of spaces (400, 410).

Description

Specification

Multilayer injection molding apparatus and method of molding laminated resin molded article using the multilayer injection molding apparatus

Technical field

The present invention relates to a multilayer injection molding apparatus capable of producing a laminated resin molded product obtained by laminating different resins, and a method of molding a laminated resin molded product, more specifically, a part on one layer The present invention relates to a multi-layer injection molding apparatus capable of producing a laminated resin molded article having a properly laminated layer, and a method of forming a laminated resin molded article.

Background art

Resin molded articles obtained by laminating different resins on one layer are used in many situations. For example, it is often used for the inner wall of automobile doors and instrumental panels.

Patent Document 1 discloses an example of a method of molding such a laminated resin molded product.

FIG. 7 shows a method for molding a laminated resin molded product disclosed in Patent Document 1.

The female mold (100) and the male mold (110) are prepared as shown in Fig. 7 (a). The female mold (100) has a recess (101) on the surface facing the male mold (110), and the male mold (110) has a protrusion (111) on the surface facing the female mold (100).

When the male mold (110) shown in FIG. 7 (b) moves toward the female mold (100), the convex portion (111) is fitted into the concave portion (101), and the top of the convex portion (111) A first cavity (120) is formed between the surface (112) and the bottom surface (102) of the recess (101).

The female mold (100) comprises a plurality of flow paths (in FIG. 7 (b) two flow paths (103, 104) are shown). One end of the flow path (103, 104) communicates with the first cavity (120), and the other end communicates with an injection nozzle (not shown) for injecting the molten resin.

[0004] The injection nozzle force shown in Fig. 7 (c) When the melted resin is injected, the melted resin flows into the first cavity (120) through the flow path (103). . The molten resin that has flowed into the first cavity (120) solidifies in the first cavity (120) and is formed into the shape of the first cavity (120) to form a base layer (130). After the base layer (130) shown in FIG. 7 (d) is molded, the male mold (110) moves by a predetermined amount in the direction away from the female mold (100), and the upper surface of the base layer (130) and the recess (101). Form a second cavity (121) with the bottom surface (102) of

As shown in FIG. 7 (e), a resin different in type from the resin forming the base layer (130) from the flow path (104) is injected into the second cavity (121) and added onto the base layer (130). The layers (131) of the are cast and stacked.

As shown in Fig. 7 (f), after the additional layer (131) is molded, the female die (130) is also moved away from the male die (101), and a laminated resin molded article (132) is produced. Is taken out.

Patent Document 1: Japanese Patent Application Laid-Open No. 2002-283389

Disclosure of the invention

Problem that invention tries to solve

[0006] The method for molding a laminated resin molded product disclosed in Patent Document 1 is an excellent method that can mold a laminated resin molded product (132) that does not complicate the mold structure, It is very difficult to stack the additional layer (131) only in a partial area on the base layer (130). FIG. 8 shows a method of forming and laminating an additional layer (131) only in a partial region on the base layer (130) by applying the mold structure shown in FIG.

[0007] In order to dispose the additional layer (131) only in a partial region on the base layer (130) as shown in FIG. 8 (a), the female die (100) and the first block (105) It is necessary to adopt a split structure consisting of the second block (106). The first block (105) and the second block (106) are movable independently of each other. Incidentally, before the molding step, the first block (105) and the second block (106) are disposed at a position where the recess (101) is formed and the bottom surface (102) of the recess (101) is flat. Ru. Further, the flow path (103) is disposed in the first block (105), and the flow path (104) is disposed in the second block (106 M rule).

Similar to the process shown in FIG. 7 (b) as shown in FIG. 8 (b), the male mold (110) moves so as to approach the female mold (100), and the convex formed on the male mold (110). The part (111) fits into the recess (101) and forms the first cavity (120).

Similarly to the process shown in FIG. 7 (c) shown in FIG. 8 (c), the molten resin flows from the flow path (103) into the first cavity (120) and the base layer (130) is molded. . After the formation of the base layer (130) as shown in FIG. 8 (d), the second block (106) moves in the direction away from the male mold (110), and the second cavity (121) is formed. , The second cavity (121) occupies a partial area on the substrate (130).

As shown in Fig. 8 (e), the melted resin from the flow path (104) is injected into the second cavity (121), and an additional layer (131) which occupies a partial region on the base layer (130). Is molded.

Similarly to the process of 07 (f) shown in FIG. 8 (f), the male die (110) is then moved away from the female die (100), and the laminated resin molded product (132) is taken out.

If a layer made of another resin is laminated on a partial region of the upper surface of the base layer (130) as shown in FIG. 8, it is necessary to adopt a divided structure for the female die (100). In addition, it will lead to the complexity of the mold structure. Although not shown in FIG. 8, in addition to the split structure, a drive mechanism is also required to move the first block (105) and the second block (106) independently and independently. Furthermore, at the same time of the control system to control this drive mechanism

In addition to the complication of the mold structure, the quality of the resulting laminated resin molded product (132) is also lowered. Due to adopting the dividing structure for the female mold (100) as described above, a protrusion (burr) along the dividing line is formed in the portion of the base layer (130) corresponding to the dividing line of the dividing structure. It will be made. In order to eliminate this protrusion, it will be necessary to separately provide a protrusion removing step.

[0011] After molding of the base layer (130), the base layer (130) is installed on another mold apparatus, and the base layer (130) is installed in order to avoid complication of the mold structure and deterioration of the laminated resin molded article (132). 130) A means of forming and laminating an additional layer (131) only in a partial area on the upper surface can be considered. According to such a method, it is necessary to use a plurality of mold devices, and the molding process is complicated. Will be invited

[0012] The present invention has been made in view of the above-mentioned circumstances, and there is provided a multilayer injection molding apparatus and a multilayer injection molding apparatus for molding and laminating an additional layer only in a partial region on one layer. It is an object of the present invention to provide a method for forming a laminated resin molded article having a V-shaped structure.

Means to solve the problem

[0013] The invention according to claim 1 comprises at least two types of thermoplastic resins. And the volume of the cavity (300) attached to the movable disc (214) and the fixed disc (213) and formed internally, and the plurality of injection devices (231, 232) for independent plasticization and independent filling injection. A multilayer injection molding apparatus (200) comprising a mold (210) capable of reducing and expanding the size and a mold clamping apparatus (220) for opening and closing the mold (210), wherein at least one of the cavities (300) The portion is provided with a buttock molding area (304) for molding a flat standing surface (29) parallel to the direction of movement of reduction and expansion of the volume of the cavity (300), and the plurality of injection devices (231) , 232), after filling the whole area of the cavity (300) with the thermoplastic resin, the volume of the cavity (300) is expanded to form a new cavity, The filled resin in the buttocks molding area (304) will cause the new cavity to Each of the plurality of spaces (400, 410) is divided into (400, 410), and the flow path of the molten resin from the injection device (231, 232) and the flow path communicating with one of the plurality of injection devices. A multi-layer injection molding apparatus (200) characterized in that a valve (239) selectively blocking the valve is provided.

The invention according to claim 2 comprises a plurality of injection devices (231, 232) for independently plasticizing and independently injecting at least two thermoplastic resins, and a movable plate (214). A mold (210) attached to the fixed plate (213) and the fixed plate (213) and capable of reducing the volume of the cavity (300) formed inside, and a mold clamping device (220) for opening and closing the mold (210). A multi-layered injection molding apparatus (200), wherein at least one portion of the cavity (300) is a flat standing surface parallel to the direction of movement of the cavity (300) for reduction and enlargement. 29), and the volume of the cavity is enlarged when resin is injected from one of the plurality of injection devices (231, 232), and When a new cavity for resin filling is formed, the buttock molding area (304 ) Separates the new cavity into a plurality of spaces (400, 410), and each of the plurality of spaces (400, 410) communicates with one of the plurality of injection devices (231, 232). A multilayer injection molding apparatus (200) characterized in that a flow path (215, 216) to be used and a valve (239) for selectively blocking the flow of molten resin from the injection device (231, 232) are provided. .

The invention according to claim 3 is that each of the injection devices (231, 232) The multilayer injection molding apparatus (200) according to claim 1 or 2, characterized in that means are independently provided for controlling the opening and closing of the flow path (215, 216).

In the invention described in claim 4, the multilayer injection molding apparatus (200) is made of thermoplastic resin by repeating injection filling of the resin and expansion operation of the cavity (300). An article (1), wherein the length in the expansion / contraction direction of the buttocks molding area (304) is not less than the total thickness of the layers constituting the laminated resin molded article (1) A multi-layered injection molding apparatus (200) according to claim 1 or 2, characterized in that

The invention according to claim 5 is characterized in that the mold (210) is clamped by the clamping device (220), and the cavity (300) having the first volume inside the mold (210) is obtained. Forming a step, opening a valve (239) of the flow passage (215, 216) passing through the cavity (300), and injecting a molten resin into the cavity (300); After being injected, the valve (239) is closed, and the molten resin injected into the cavity (300) is kept cooled for a predetermined time, the mold (210) is opened, and the resin is cooled Forming a cavity (400, 410) with a second volume between the molten resin and the inner wall of the mold (210) and passing the newly formed cavity (400, 410) Opening the flow path valve (239) and injecting the molten resin into the newly formed cavity (400, 410); After being injected into the formed cavity (400, 410), the valve (239) of the flow path (215, 216) leading to the newly formed cavity (400, 410) is closed, and the new There is a step of cooling and holding the molten resin injected into the cavity (400, 410) for a predetermined time, and a step force of opening the mold and taking out the laminated resin molded product (1) from the mold (210). It is a molding method of laminated resin molded products.

The invention according to claim 6 is characterized in that the new cavity (400, 410) is sequentially formed according to the number of laminated layers of the resin layer constituting the molded article (1); Between the step of injecting the molten resin into the primary cavity (400, 410) and the step of cooling and holding the molten resin in the new cavity (400, 410). It is a shaping | molding method of the lamination | stacking resin molded article of description.

The invention according to claim 7 is characterized in that at least one of the molten resins is a blowing agent. After the injection of the desired amount of the molten resin mixed with the foaming agent is completed, the valve (239) is closed and the mold (210) is opened so as to achieve the desired expansion ratio. A method for molding a laminated resin molded article (1) according to claim 5 or 6, characterized in that

Effect of the invention

[0015] According to the invention described in claims 1 and 2, the cavity volume can be reduced and expanded, and a new cavity can be formed by expanding the cavity volume. . The new cavity is divided by the resin filled in the buttock molding area. Therefore, even if the molten resin is injected into one of the divided cavities, a partially laminated layer is provided on the upper surface of the first layer, into which the molten resin injected into the other cavity can not flow. Is possible.

According to the invention described in the third aspect, the injection start and stop of the molten resin can be suitably controlled.

According to the invention described in claim 4, a plurality of resin layers can be stacked on a part of the first layer.

[0016] According to the invention described in claim 5, the cavity volume can be reduced and expanded, and it is possible to form a new cavity by enlarging the cavity volume. The new cavity is divided by the resin filled in the buttocks molding area. Therefore, even if the molten resin is injected into one of the divided cavities, the partially laminated layer is formed on the upper surface of the first layer in which the molten resin injected into the other cavity can not flow. It becomes possible to provide.

According to the invention described in claim 6, a plurality of resin layers can be stacked on a part of the first layer.

According to the invention of claim 7, it is possible to form a homogeneous foam layer. BEST MODE FOR CARRYING OUT THE INVENTION

Hereinafter, a laminated resin molded article according to the present invention, a mold structure for molding the laminated resin molded article, and a molding method for molding the laminated resin molded article will be described. This will be described with reference to the figure. The following embodiments are merely illustrative of the present invention. It is also possible to employ different shapes of laminated resin moldings and mold constructions.

FIG. 1 shows a laminated resin molded article. Fig. 1 (a) is a plan view of the laminated resin molded product, and Fig. 1 (b) is a cross-sectional view taken along the line A-A of Fig. 1 (a).

The laminated resin molded product (1) comprises a base layer (2) and an additional layer (3) laminated on the upper surface of the base layer (2).

The base layer (2) has a first area (21) disposed on the left side in FIG. 1, a second area (22) disposed on the right side in FIG. 1, a first area (21), and a second area. It comprises a buttock (23) disposed between the area (22). An additional layer (3) is stacked on the second region (22).

The collar portion (23) extends from the right edge of the first region (21), and is bent and bent downward in the perpendicular direction. Then, the lower end side surface of the buttocks (23) and the second area (22) are connected, and the second area (22) is bent in a direction perpendicular to the buttocks (23) and extends rightwardly. It is set up. The surface on the right side of the buttocks (23) is the standing surface (29) described later.

The second region (22) is connected to the connecting portion (221) which is connected to the collar portion (23) and extends rightward, and connected to the connecting portion (221) and connected to the connecting portion (221). It comprises an inclined portion (222) which is inclined upward with a predetermined inclination angle, and a main portion (223) which is connected to the inclined portion (222) and extends horizontally to the right.

The additional layer (3) is stacked on the upper surface of the second region (22), and has the same cross-sectional shape as the second region (22). That is, the additional layer (3) is connected to the erected surface (29) of the ridge (23) and extends rightward at right angles to the ridge (23); 31) connecting to the inclined portion (32) connected to the connecting portion (31) and inclined upward with a predetermined inclination angle with respect to the connection portion (31), and extending horizontally toward the right The main part (33) will also be a force.

The upper surface of the main portion (33) of the additional layer (3) and the upper surface of the first region (21) of the base layer (2) are flush with each other.

Although each portion of the resin molded product (1) shown in FIG. 1 is formed in a planar shape, the present invention is not limited to this, and a convex portion may be formed even if it is formed in a curved surface shape. It may have a recess. In addition, it is necessary for the standing surface of the collar portion (23) to have a linear profile in longitudinal section.

1 (a) shows a resin molded product (1) whose entire shape is rectangular in plan view, but the shape in plan view is not limited to this, and may be a circular, elliptical, triangular or other polygonal shape A desired shape can be adopted.

Furthermore, a multi-layer structure having more layers than the two-layer resin molded product may be suitably employed.

Any resin may be used as the resin forming each layer of the resin molded product (1). For example, for the base layer (2), polypropylene, polycarbonate, polyethylene terephthalate, ABS resin, polystyrene-based thermoplastic resin 'elastomeric resin, polyolefin-based thermoplastic resin, elastomeric resin, polyester-based thermoplastic resin-elastomer Resins, polybutadiene-based thermoplastic elastomers, elastomers, and thermoplastic thermoplastic elastomers to which an inorganic foaming agent is added may be used.

Also, for the additional layer (3), similarly, polypropylene, polycarbonate, polyethylene terephthalate, ABS resin, polystyrene-based thermoplastic resin 'elastomeric resin, polyurethane-based thermoplastic resin' elastomeric resin, polyester-based thermoplastic resin K · Elastomer resin, polybutadiene-based thermoplastic resin · Elastomer resin · These thermoplastic plastic elastomers may be used with an inorganic foaming agent added.

By making the resin constituting the base layer (2) different from the resin constituting the additional layer (3), a resin molded article having various physical properties can be obtained. Therefore, it is necessary to select a resin to be used in combination so as to obtain desired physical properties.

FIG. 2 is an entire configuration view of an injection molding apparatus used for molding the resin molded product (1) shown in FIG.

The injection molding apparatus (200) comprises a mold (210), a mold clamping apparatus (220), a first injection apparatus (231), a second injection apparatus (232) and a control apparatus (240).

The mold (210) comprises a female mold (211) and a male mold (212). The female die (211) is attached and fixed to the fixed plate (213). The male mold (212) is attached to the movable platen (214) and is movable back and forth in the direction approaching and away from the female mold (211) as the mold clamping device (220) operates.

A recess (217) is formed on the surface facing the male mold (212) of the female mold (211), and a convex part (218) is formed on the surface facing the female mold (211) of the male mold (212). When the male mold (212) is moved toward the female mold (211) by the mold clamping device (220), the convex part (218) is fitted into the concave part (217) . Then, a cavity (300) of a predetermined shape is formed between the top surface (301) of the convex portion (218) and the bottom surface (302) of the concave portion (217).

A first channel (215) and a second channel (216) are formed inside the female die (211), and one end of the first channel (215) and the second channel (216) is a female die. It communicates with a cavity (300) formed between (211) and the male mold (212). The other end of the first channel (215) communicates with the end of the first injection device (231), and the other end of the second channel (216) communicates with the tip of the second injection device (232). Do.

The mold clamping device (220) includes a motor (229), and along with the operation of the motor (229), the mold clamping device (220) moves the movable plate (214) back and forth, thereby a male mold (212) also moves back and forth. The clamping device (220) further comprises a sensor (222) for detecting the position of the movable platen (214). The sensor (222) force signal is sent to the clamping device controller (241) of the controller (240). The clamping device control unit (241) determines the amount of rotation of the motor (229) in response to the sensor (222) force signal, sends a signal to the motor (229), and the motor (229) Operate based on. As a result, the position of the movable plate (214) is accurately controlled, and the operation of opening the mold is performed under control.

Although the mold clamping device (220) shown in FIG. 2 is a toggle type electric mold clamping device (220), the present invention is not limited to this, and the position control of the movable platen (214) is accurate. As long as it can be carried out well and sufficient mold clamping force can be applied to the mold (210), it can be adopted as appropriate. For example, a hydraulically operable form may be adopted, and instead of the toggle type, a direct pressure type may be adopted.

The injection device (231, 232) includes a barrel (233) and a screw (235) disposed inside the barrel (233) and provided with a screw flight (234).

The barrel (233) comprises a hopper (236), from which the resin is supplied. The rear end of the screw (235) is connected to the injection servomotor (237) and the screw rotation servomotor (238). The injection servomotor (237) moves the screw (235) back and forth, and the screw rotation servomotor (238) rotates the screw (235).

Further, a heater (not shown) is disposed on the outer peripheral surface of the barrel (233), and the barrel (233) can be heated.

Pellets inside the hopper (236) by the rotation operation of the servomotor for screw rotation (238) Resin is supplied into the barrel (233). The resin supplied in the barrel (233) is melted by the heated barrel (233). Then, the melted resin is subjected to the kneading and compression action from the screw flight (234) by the rotation of the screw (235), and is sent forward of the screw (235).

A rotary valve (239) is disposed at the tip of the barrel (233). The rotation of the rotary valve (239) opens and closes the flow passage at the tip of the barrel (233). The molten resin fed to the front of the screw (235) is also driven by the screw (235) advanced by the injection servomotor (237) when the valve (239) is in the open state. It is injected and reaches the cavity (300) through the flow path (215, 216) formed inside the female die (211).

The control device (240) includes a clamping device control unit (241), a clamping condition setting unit (242), an injection device control unit (243), and an injection condition setting unit (244).

As described above, the mold clamping device control unit (241) receives the signal of the sensor (222) and controls the mold clamping device (220) based on this signal. Further, a predetermined operation flow and operation conditions of the mold clamping device (220) are input through the mold clamping condition setting unit (242), and based on this input, the mold clamping device control unit (241) operates the mold clamping device (220). Control the operation of

The injection device control unit (243) controls the operation of the injection servomotor (237) and the screw rotation servomotor (238) according to the setting conditions inputted through the injection condition setting unit (244).

FIG. 3 is a flowchart showing a molding method for molding the laminated resin molded article (1) of FIG. 1 using the injection molding apparatus (200) shown in FIG.

The method for molding the laminated resin molded product (1) is composed of the first cavity forming step, the base layer forming step, the second cavity forming step and the laminating step.

FIG. 4 is a state diagram of the mold (210) in the first cavity forming step.

In the first cavity forming step, the mold clamping device (220) operates in response to the control signal from the mold clamping device control unit (241) to bring the male mold (212) closer to the female mold (211) side. And the convex part (218) from which the surface force on the female mold (211) side of the male mold (212) also protrudes is in the male mold (recess (217) formed on the surface of the 212 M rule) of the female mold (211). Then, a first cavity (300) is formed between the top surface (301) of the projection (218) and the bottom surface (302) of the recess (217). In the state shown in FIG. 4, the convex portion (218) is fitted into the concave portion (217) as much as possible.

The first cavity (300) is formed by bending downward at a right angle from the first molding area (303) located as the space on the left side in FIG. 4 and the first molding area (303) right edge And a second molding area (305) which communicates with the lower right side of the buttock molding area (304) and is formed toward the right. The surface on the side of the second molding area (305) of the buttocks molding area (304) forms the standing surface (29) of the collar section (23) shown in FIG. 1, and the male mold (212) moves It is parallel to the possible directions (up and down in Figure 4).

The second molding area (305) is connected to the buttock molding area (304), and is connected to the connection molding area (351) extending horizontally to the right and the connection molding area (351) to the right edge. The connecting part molding area (352) which inclines upward at a predetermined angle with respect to the connecting part molding area (351) and the right edge of the inclined part molding area (352) are connected horizontally to the right It consists of an extending main part molding area (353).

The first flow path (215) formed in the female die (211) communicates with the first molding area (303), and the second flow path (216) forms the main part of the second molding area (305). In communication with region (353).

The clamping device (220) loads a predetermined clamping force on the mold (210), and the mold (210) is fixed in the state shown in FIG.

After the first cavity forming step, a base layer forming step is performed. In the base layer molding process, the valve (239) provided at the inner end of the barrel (233) of the first injection device (231) is also switched to the open state. Then, the injection servomotor (237) is operated to move the screw (235) toward the end of the barrel (233) to perform an injection operation.

The molten resin injected from the inside of the barrel (233) reaches the inside of the first cavity (300) through the flow path (215) inside the female mold (211).

Then, after adjusting the position of the screw (235) and holding pressure against the molten resin inside the first cavity (300) for a predetermined time, the valve (239) is switched to the closed state again.

This pressure holding time is measured by a timer incorporated in the control device (240), and when the measured value of the timer becomes equal to the value set by the mold clamping condition setting unit (242), the mold clamping device The control unit (241) sends a signal to the motor (229) of the clamping device (220), and causes the clamping device (220) to mold. The opening operation is performed to start the second cavity forming process. The pressure holding time to be set is set to such a length that the molten resin injected into the first cavity (300) can be sufficiently cooled and solidified. The molten resin in the first cavity (300) is cooled and solidified during the pressure holding time to form the base layer (2).

During the second cavity forming step, first, the load of the mold clamping force from the mold clamping device (220) to the mold (210) is released. Then, the mold clamping device (220) moves the male mold (212) away from the female mold (211). Movement of the male mold (212) is monitored by the sensor (222), and the male mold (212) accurately moves by the movement amount determined by the clamping condition setting device (242).

FIG. 5 shows a state in which the male mold (212) has been moved away from the female mold (211) by a predetermined amount of movement in the second cavity forming step.

The base layer (2) molded in the base layer molding step adheres to the top surface (301) of the convex portion (218) and separates from the bottom surface (302) of the concave portion (217) as the male mold (212) moves. .

Here, the amount of movement of the male mold (212) is the length of the surface on the second molding area (305) side of the buttocks molding area (304) (ie, the base layer (2) formed in the base layer forming process). The second region (22) is set smaller than the height of the ridge (23) defined as the distance from the upper surface to the upper end of the ridge (23). As a result, a new cavity (400, 410) is formed on the upper surface of the base layer (2).

New cavities (400) are formed on the first region (21) of the base layer (2) formed in the base layer forming process. A new cavity (410) is formed on the second region (22) of the base layer (2) formed in the base layer forming step.

With respect to the shape of the new cavity (400), the upper and lower surfaces of the new cavity (400) are both flat as in the first region (21) of the base layer (2) formed in the base layer forming step. Yes, the left side of the new cavity (400) is flush with the left side of the base layer (2) and the right side of the new cavity (400) is the ridge (23) of the base layer (2). It is flush with the right side of the

The shape of the new cavity (410) is substantially the same as the second region (21) of the base layer (2) formed in the base layer forming step. The new cavity (410) is connected to the connection part molding area (411) connected to the ridge part (23) molded in the base layer molding process and the right end edge of the connection part molding area (411) and is also specified. It connects with the right end edge of the slope part molding area (412) which inclines upward at the inclination angle and extends rightward, and the right end edge of the slope part molding area (412), and It consists of the main part molding area (413) extending horizontally.

The pair of new cavities (400, 410) are separated by the ridge portion (23) of the base layer (2) formed in the base layer forming step. The new cavities (400, 410) are both enclosed by the bottom surface (302) of the recess (217) and the inner peripheral surface of the recess (217) and the upper surface of the base layer formed in the base layer forming step (2) Even if the molten resin is injected into the new cavity (400, 410), the molten resin does not leak from the cavity (400, 410). In the present embodiment, the new cavity (410) is taken as the second cavity (410), and the molten resin is injected from the second injection device (232) into the second cavity (410).

After the second cavity formation step is performed as described above, and a new cavity (400, 410) having a predetermined thickness is formed on the upper surface of the base layer (2), a lamination step is performed.

In the stacking process, the valve (239) provided at the inner end of the barrel (233) of the first injection device (232) is switched from the closed state to the open state. Then, the injection servomotor (237) is operated to move the screw (235) toward the end of the barrel (233) to perform an injection operation. The molten resin injected from the inside of the barrel (233) reaches the inside of the second cavity (410) through the flow path (216) inside the female mold (211).

The molten resin in the second cavity (410) is blocked by the ridge (23) of the base layer (2) formed in the base layer forming step, and does not flow into the new cavity (400). . Furthermore, since the second cavity (410) as described above is kept airtight, there is no possibility that the partial force of the mold (210) will flow out.

Therefore, the molten resin injected into the second cavity (410) is connected to the right side surface of the buttocks (23) and the second cavity (22) formed on the second region (22) of the base layer (2) It is molded into a layer imitating the shape of 410).

After the molten resin was injected into the second cavity (410), the position of the screw (235) was adjusted, and the pressure was held against the molten resin inside the second cavity (410) for a predetermined time. After that, the valve (239) is switched to the closed state again.

The holding time is measured by the timer incorporated in the control device (240) as in the base layer molding process, and the measured value of the timer is equal to the value set by the clamping condition setting unit (242). When the mold clamping device controller (241) sends a signal to the motor (229) of the mold clamping device (220). Feeding, causing the mold clamping device (220) to perform a mold opening operation, and moving the male mold (212) in a direction away from the female mold (211). The pressure holding time to be set is set to such a length that the molten resin injected into the second cavity (410) can be sufficiently cooled and solidified. The molten resin in the second cavity (410) is cooled and solidified during the pressure holding time to form the additional layer (3).

If the resin molded into the base layer (2) or the additional layer (3) is a foamed resin containing a foaming agent, the following operation is carried out in the base layer forming step and the laminating step. May be

After closing the valve (239), the male mold (212) is gradually separated from the female mold (211) to gradually expand the volume of the cavity (300, 410). For example, after moving the male mold (212) by about 2 mm, the movement of the male mold (212) is stopped for about 2 seconds, and the position is maintained. By repeating this process a plurality of times and gradually expanding the volume of the cavity (300, 410), it is possible to obtain uniform foaming in the layer.

Such an operation can be set in advance by the clamping condition setting unit (242), and can be performed accurately by the operation of the clamping device (220) whose position is controlled by the signal of the sensor (222). is there.

In addition, such an operation mode is appropriately selected and determined according to the type of resin used.

After the steps up to the laminating step are completed as described above, the male mold (212) is further moved in a direction to separate the female mold (211) force, and the top surface (301) of the convex portion (218) The stuck laminated resin molded product (1) is taken out.

[0045] FIG. 6 shows various forms of laminated resin molded articles (1) obtained according to the principle of the present invention described above. The present invention is not limited to the illustrated example, and other various forms can be obtained according to the principle of the present invention.

Fig. 6 (a) shows a form in which a plurality of additional layers (3) are laminated on the second region (22) of the base layer (2). The laminated resin molded product (1) shown in Fig. 6 (a) Can be obtained by

After molding the base layer (2), the male mold (212) is moved by a movement amount smaller than that of the male mold (212) shown in FIG. A plurality of resin injection flow paths are formed in the female die (211), and the injection devices connected to the flow paths are respectively mounted. Multiple Flows in the Cavity The valve (239) of one of the passages is opened, and the molten resin is injected into the cavity formed by the movement of the male die (212). Then, a desired amount of molten resin is injected and held for a predetermined time, and the molten resin is cooled and solidified.

Then, after the molten resin is cooled and solidified, the male mold (212) is moved again by a minute amount to form a new cavity, and this new cavity is subjected to other channels from the other channels in the same manner as described above. The molten resin is injected, and an additional layer is further laminated on the additional layer. Repeating this, a plurality of additional layers (3) can be provided on the second region (22).

FIG. 6 (b) shows an example in which a molten resin is injected and molded into the cavity (400) shown in FIG.

The laminated resin molded product (1) shown in FIG. 6 (b) is provided with a plurality of flow paths for molten resin injection communicating with the cavity (400) shown in FIG. 5, and the injection device is connected to each flow path. It can be obtained by

That is, after the molten resin is injected from one channel and the base layer (2) is molded, the molten resin is injected from the other channel and added onto the first region (21) of the base layer (2). Layers (3) can be laminated. In this case, the upper end of the ridge portion (23) of the base layer (2) stops the molten resin injected onto the first region (21). Further, as shown in the example of FIG. 6 (a), it is possible to mold a plurality of additional layers (3) also in the example of FIG. 6 (b).

FIG. 6 (c) and FIG. 6 (d) show a laminated resin molded product (1) having a large number of laminated regions. Fig. 6 (c) is a front view of the laminated resin molded product (1), and Fig. 6 (d) is a plan view of the laminated resin molded product (1).

The laminated resin molded product (1) shown in FIGS. 6 (c) and 6 (d) has a flat plate portion and a ridge portion (23) having a cross shape in a plan view, erected at right angles to the upper surface force of the flat plate portion. The upper surface of the flat portion is divided into four sections by the ridge (23). And in each section, an additional layer (3) is stacked.

Thus, it is also possible to form stacked portions on three or more regions.

In addition, it is also possible sufficiently to provide a laminated portion on a single region as shown in FIG. 6 (e).

[0048] The laminated resin molded product (1) of the present invention as is evident from the laminated resin molded product (1) of various forms of Fig. 6 has the following common features. The base layer (2) comprises a ridge (23) having a flat erected surface (29) and an area connected to the ridge (23) upper end side and Z or lower end side. If the additional layer (3) is laminated on the area connecting with the upper end side of the ridge (23), the additional layer (3) is a surface with respect to the standing surface (29) of the ridge (23). It has one edge. If the additional layer (3) is stacked on the area connected with the lower end side of the ridge (23), the additional layer (3) is connected with the erected surface (29) of the ridge (23) With an edge that The upper surface of the additional layer (3) is formed parallel to the upper surface of the region of the base layer (2) on which the additional layer (3) is laminated.

Industrial applicability

The present invention is suitably applied to a door inner wall portion or instrumental panel of a car, a molding method thereof and a mold apparatus used for the molding method.

Brief description of the drawings

FIG. 1 is a view showing an example of a laminated resin molded product according to the present invention.

FIG. 2 is an entire configuration view of an injection molding apparatus used for molding a laminated resin molded product according to the present invention.

FIG. 3 is a flowchart of a method for molding a laminated resin molded product according to the present invention.

FIG. 4 is a view showing a mold in a first cavity forming step of the method for molding a laminated resin molded product according to the present invention.

FIG. 5 is a view showing a mold of a second cavity forming step of the method for molding a laminated resin molded product according to the present invention.

FIG. 6 is a view showing various forms of a laminated resin molded product according to the present invention.

FIG. 7 is a view showing an example of a manufacturing process of a conventional laminated resin molded product.

FIG. 8 is a view showing an application example of a manufacturing process of a conventional laminated resin molded product.

Explanation of sign

[0051] 1-layered resin molded product

2 base layer

210 · ·, mold

211 ... Female mold

212 · · · Male 215 ·· · · Flow path

216 · · · Flow path

217 · · · Recess

218 ·-convex part

23 · · ·-Department

29 ··· · · Set up surface

3 · · · '' · · additional layer

300 · • 'Circuit

301 · · · Heaven face

302 • •, bottom

304 · ,,, buttock molding area

Claims

The scope of the claims

[1] A plurality of injection devices (231, 232) for independently plasticizing and independently charging and injecting at least two types of thermoplastic resins,

A mold (210) attached to the movable plate (214) and the fixed plate (213) and capable of reducing and expanding the volume of the cavity (300) formed therein;

A multilayer injection molding apparatus (200) comprising a mold clamping device (220) for opening and closing the mold (210), wherein

In at least one portion of the cavity (300), there is a ridge molding area (304) for molding a flat standing surface (29) parallel to the direction of movement of reduction and expansion of the volume of the cavity (300). Provided

After the injection device of one of the plurality of injection devices (231, 232) fills the entire area of the cavity (300) with the thermoplastic resin, the volume of the cavity (300) is expanded, and a new cavity is created. The filled resin in the buttocks molding area (304) divides the new cavity into a plurality of spaces (400, 410);

In each of the plurality of spaces (400, 410), a flow path communicating with one of the plurality of injection devices and a valve (239) selectively blocking the flow of molten resin from the injection devices (231, 232). A multi-layer injection molding apparatus (200) characterized in that

[2] A plurality of injection devices (231, 232) for independently plasticizing and independently charging and injecting at least two types of thermoplastic resins,

The volume of the cavity is expanded when and after the resin is injected from one of the plurality of injection devices (231, 232), and a new cavity is formed to be filled with the next resin. The resin in the buttock molding area (304) splits the new cavity into multiple spaces (400, 410) when

In each of the plurality of spaces (400, 410), a flow path (215, 216) communicating with one of the plurality of injection devices (231, 232) and the molten resin of the injection device (231, 232). A multilayer injection molding apparatus (200) characterized in that a valve (239) for selectively blocking the flow of water is provided.

[3] The apparatus according to claim 1 or 2, wherein the injection device (231, 232) is independently provided with means for controlling the opening and closing of the flow path (215, 216). A multi-layer injection molding apparatus (200) according to claim 2.

[4] The multilayer injection molding apparatus (200) repeats the injection filling of the resin and the expansion operation of the cavity (300) to obtain a laminated resin molded product (1) made of thermoplastic resin, The length in the scaling direction of the buttock molding area (304) is equal to or greater than the total thickness of the layers constituting the laminated resin molded article (1). Item 6. A multilayer injection molding apparatus (200) according to Item 2 or 3.

[5] forming a cavity (300) having a first volume inside the mold (210) by clamping the mold (210) with a mold clamping device (220);

Opening a valve (239) of a flow path (215, 216) passing through the cavity (300) and injecting a molten resin into the cavity (300);

After the desired amount of molten resin is injected, the valve (239) is closed, and the molten resin injected into the cavity (300) is cooled and held for a predetermined time;

Opening the mold (210) and newly forming a cavity (400, 410) with a second volume between the cooled molten resin and the inner wall of the mold (210);

Opening the groove (239) in the flow passage leading to the newly formed cavity (400, 410) and injecting the molten resin into the newly formed cavity (400, 410), and a desired amount of After the molten resin is injected into the newly formed cavity (400, 410), the valve (239) of the flow path (215, 216) leading to the newly formed cavity (400, 410) is formed. Close and place molten resin injected into the new cavity (400, 410) Holding the cooling for a fixed time,

A method for molding a laminated resin molded product, which has a step force that is performed by releasing the mold and taking out the laminated resin molded product (1) from the mold (210).

[6] According to the number of laminated layers of the resin layer constituting the molded article (1), the new cavity is sequentially

Forming (400, 410), injecting molten resin to the new cavity (400, 410), and cooling the molten resin in the new cavity (400, 410). The method for molding a laminated resin molded product according to claim 5, wherein the floor is repeated.

[7] A foaming agent is mixed with at least one of the molten resins,

After the injection of the desired amount of the molten resin mixed with the blowing agent is completed, the valve (239) is closed, and the mold (210) is opened so as to obtain a desired expansion ratio. A method of molding a laminated resin molded article (1) according to claim 5 or 6, characterized in that