JP2014226795A - Method for manufacturing molding structure - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method for manufacturing a molding structure which can supply a part of a molten resin forming a molding to a surface opposite to a molding surface of a molding in a substrate, and can suppress the deformation of the substrate caused by the pressure of the molten resin.SOLUTION: A method for manufacturing a molding structure 10 comprising a substrate 12 and a molding 15 includes: a press molding process of press-molding the substrate 12 by a first molding die 30 and a second molding die 50; and an injection process of injecting the molten resin into a cavity 31. In the injection process, a part of the molten resin injected into the cavity 31 through a through hole 13 formed in the substrate 12 is made to flow into a first molding space S1, and a second movable mold 52 is made to abut on the other surface 12B. Subsequently, in a movable mold-moving process, the volume of the first molding space S1 is reduced, and a second molding space S2 communicating with the first molding space S1 is formed between the second movable mold 52 and the other surface 12B.

Description

  The present invention relates to a method for manufacturing a molded structure.

  Conventionally, for example, the following Patent Document 1 is known as a method for producing a molded structure including a plate-like base material and a molded body injection-molded on the base material. Patent Document 1 below discloses a manufacturing method in which a base material (inner box) is sandwiched between a pair of molding dies, and then a molding material is injected into a cavity formed in the molding die to form a molding on the base material. Have been described. Moreover, in patent document 1, by forming a through-hole in a base material, a part of molding material (molten resin) is formed in the back surface (surface on the opposite side to the surface where a molded object is shape | molded) through a through-hole. Arranged. Thereby, the joint strength of the molded object with respect to a base material can be made high.

JP 11-337254 A

  In the manufacturing method shown in Patent Document 1, as shown in FIG. 9, in a pair of molds 5 and 6, a molded body molding space 2 (cavity) for molding a molded body on one surface 1 </ b> A side of the substrate 1. ). And the 1st shaping | molding space 3 is formed in the other surface 1B side of the base material 1. FIG. When the molten resin is injected into the molded body molding space 2, a part of the molten resin is supplied to the first molding space 3 through the through holes 4 formed in the base material 1. Thereby, a part of molten resin for shape | molding a molded object can be supplied to the other surface 1B side of the base material 1, and the joint strength of a molded object can be made high.

  However, when the first molding space 3 as described above is formed, a gap is generated between the hole edge 4 </ b> A in the through hole 4 of the substrate 1 and the molding die 6. Thereby, as shown in FIG. 10, when the pressure F1 of the injected molten resin 7 acts on one surface 1A of the base material 1, the hole edge portion 4A of the base material 1 faces the first molding space 3 side. There is a risk of deformation. Thereby, there is a concern that the first molding space 3 may be blocked by the base material 1 or the design property may be deteriorated due to deformation of the base material 1.

  The present invention has been completed based on the above-described circumstances, and a part of the molten resin injected into the molded body molding space for molding the molded body is opposite to the molding surface of the molded body in the base material. An object of the present invention is to provide a method for producing a molded structure that can be supplied onto the surface of the substrate and that can prevent the base material from being deformed by the pressure of the molten resin.

  In order to solve the above-mentioned problems, the present invention provides a molded structure comprising a base material including a fiber and a synthetic resin and having a plate shape, and a molded body injection-molded on one surface of the base material. A press molding step of press molding the base material by a first molding die facing the one surface and a second molding die facing the other surface of the base material, and the press molding step In the molded body molding space for molding the molded body, the concave body is formed in the first molded mold in a state where the base material is pressed by the first molding die and the second molding die. An injection step of injecting a molten resin; and a movable type moving step that is performed after the injection step and moves the first movable die and the second movable die provided in the second mold, respectively, In the step, the first movable mold and the While circulating a part of the molten resin injected into the molded body molding space through the resin circulation portion formed in the base material with respect to the first molding space formed between the two surfaces, The second movable mold is brought into contact with the periphery of the resin circulation part on the other surface, and in the movable mold moving step, the first movable mold is brought close to the other surface, thereby Second molding that communicates with the first molding space between the second movable mold and the other surface by reducing the volume of the molding space and moving the second movable mold away from the other surface. It is characterized by forming a space.

  In the present invention, after the molten resin is circulated through the first molding space, the volume of the first molding space is reduced and the second molding space is formed. Thereby, a part of molten resin circulated through the first molding space is supplied to the second molding space. That is, a part of the molten resin injected into the molded body molding space can be supplied to the space (the first molding space and the second molding space) opposite to the molding surface of the molded body in the base material.

  As a result, when the molten resin in the first molding space and the second molding space is hardened, the resin disposed in the resin flow section on the other surface of the base material (the surface opposite to the surface on which the molded body is molded) A resin member connected to the molded body via the is molded. Thereby, the joining strength of a molded object and a base material can be made higher. In the injection step, the molten resin is injected in a state where the second movable mold is in contact with the periphery of the resin flow portion on the other surface. If it does in this way, the situation where a part of substrate (around resin distribution part) changes with pressure of molten resin can be controlled.

  In the above configuration, the resin flow part is a through hole formed through the base material, and in the injection step, the second movable mold is used as a hole edge part of the through hole on the other surface of the base material. It can be made to contact.

  The resin circulation part can be easily formed by forming the through hole in the base material. Moreover, by forming the through hole, the rigidity around the through hole in the base material becomes relatively low. In the present invention, by bringing the second movable mold into contact with the hole edge of the through hole, it is possible to suppress the situation where the hole edge of the base material is deformed by the pressure of the molten resin.

  According to the present invention, a part of the molten resin injected into the molded body molding space for molding the molded body is supplied onto the surface of the base material opposite to the molding surface of the molded body, and by the pressure of the molten resin. The manufacturing method of the shaping | molding structure which can suppress the situation where a base material deform | transforms can be provided.

Sectional drawing which shows the manufacturing method and manufacturing apparatus which manufacture the shaping | molding structure which concerns on one Embodiment of this invention. Sectional view showing press forming process Sectional view showing through hole forming process Sectional view showing the injection process Sectional view showing the movable movement process The perspective view which shows the blade for forming a through-hole in a base material A perspective view showing a modification of the blade The perspective view which shows the modification of a blade different from FIG. Sectional view showing a conventional example Sectional drawing which shows the state which injected the molten resin in the prior art example

  An embodiment of the present invention will be described with reference to FIGS. As shown in FIG. 5, the molded structure 10 of the present embodiment includes a base material 12 having a plate shape and a molded body 15 injection-molded on the base material 12. Such a base material 12 is used, for example, for a vehicle seat back or door trim. Moreover, as the molded object 15, the rib shape | molded on the base material 12 and the fastening member (an attachment boss | hub, a clip seat, etc.) for fastening the base material 12 to another member can be illustrated.

  The base material 12 is, for example, a fiber reinforced plastic (FRP) containing fibers and a synthetic resin. Such a substrate 12 is formed, for example, by impregnating and curing a thermoplastic resin (polypropylene, polyethylene, or the like) in a fabric such as glass fiber or carbon fiber.

  As shown in FIG. 1, the molded body 15 is molded so as to protrude from one surface 12 </ b> A of the substrate 12. The molded body 15 is made of, for example, polypropylene that is a thermoplastic resin. In addition, a through hole 13 that penetrates the base material 12 in the plate thickness direction is formed at a molding portion of the molded body 15 in the base material 12.

  In the molded body 15, an insertion portion 16 inserted through the through hole 13 is integrally formed. A locking portion 17 is disposed on the other surface 12B of the base material 12 so as to cover the hole edge portion 13A of the through hole 13. The locking portion 17 is formed integrally with the inserted portion 16 and the molded body 15. Thereby, the coupling | bonding strength of the molded object 15 with respect to the base material 12 can be made higher because the latching | locking part 17 latches to the other surface 12B.

  The molding structure 10 of this embodiment is manufactured using the molding apparatus 20 shown in FIG. The molding device 20 includes a pair of molding dies 21 (first molding die 30 and second molding die 50) and an injection device 25. The injection device 25 is, for example, a screw type, and is provided in the first mold 30 in this embodiment.

  The second mold 50 is a movable mold that can move with respect to the first mold 30 (fixed mold) by a driving device (not shown) (for example, an electric motor, an air cylinder, a hydraulic cylinder, or the like). The second mold 50 can be closed and opened between the first mold 30 and the second mold 50 by moving the second mold 50 closer to and away from the first mold 30.

  In the following description, the state where the first molding die 30 and the second molding die 50 are closed is the closed state (the state shown in FIG. 2), and the state where the first molding die 30 and the second molding die 50 are opened. It shall be called an open state (state of FIG. 1).

  For example, the second mold 50 has a shape in which a facing surface 50 </ b> A facing the first mold 30 (and thus the base material 12) protrudes toward the first mold 30. Further, the first mold 30 has a shape in which the facing surface 30 </ b> A facing the second mold 50 (and thus the base material 12) is recessed corresponding to the shape of the second mold 50.

  In the closed state, as shown in FIG. 2, a base material forming space S <b> 3 for press-forming the base material 12 is formed between the first forming die 30 and the second forming die 50. Thereby, when the base 12 before molding (preboard P1) is pressed by the first molding die 30 and the second molding die 50, the preboard P1 is compression molded into a shape corresponding to the shape of the base molding space S3. The substrate 12 can be formed into a predetermined shape.

  That is, the opposing surface 30A and the opposing surface 50A are molding surfaces for molding the substrate 12 into a predetermined shape (product shape). The shapes of the facing surface 30 </ b> A and the facing surface 50 </ b> A can be changed as appropriate in accordance with the product shape of the substrate 12.

  A cavity 31 (molded body molding space) for molding the molded body 15 is recessed in the facing surface 30A of the first mold 30. The cavity 31 has a shape corresponding to the shape of the molded body 15 and is configured to communicate with the base material forming space S3 in the mold closed state (see FIG. 2).

  In addition, a resin supply path 32 that allows the molten resin injected from the injection device 25 to be supplied to the cavity 31 is formed inside the first mold 30.

  An accommodation recess 33 is formed on the bottom surface of the cavity 31 having a concave shape. A blade 34 for penetrating and forming the through hole 13 in the base material 12 is housed in the housing recess 33. The blade 34 has a shape that tapers toward the tip side (base material 12 side).

  The blade 34 is configured to be displaceable from the housing recess 33 toward the cavity 31 by a driving device (not shown) (for example, an electric motor, an air cylinder, a hydraulic cylinder, etc.).

  A concave portion 55 in which the first movable mold 51 and the second movable mold 52 are accommodated is formed on the facing surface 50 </ b> A of the second mold 50. The recess 55 is formed at a location facing the cavity 31 of the first mold 30 on the facing surface 50A.

  The first movable mold 51 is disposed at a location facing the housing recess 33 and the blade 34 in the second mold 50. The first movable mold 51 is moved in a direction approaching and separating from the other surface 12B of the substrate 12 (left-right direction in FIG. 1) by a driving device (not shown) (for example, an electric motor, an air cylinder, a hydraulic cylinder, etc.). Displaceable.

  The first movable mold 51 is configured to be able to be inserted through an insertion hole 52 </ b> B formed through the second movable mold 52. The second movable mold 52 can be disposed so as to surround the first movable mold 51 by inserting the first movable mold 51 into the insertion hole 52B.

  Further, as shown in FIG. 4, the facing surface 51 </ b> A of the first movable mold 51 that faces the other surface 12 </ b> B of the base material 12 overlaps with the through-hole 13 formed in the base material 12 in plan view. The area is larger than that of the through hole 13.

  The second movable mold 52 is moved toward and away from the other surface 12B of the substrate 12 by a driving device (not shown) (for example, an electric motor, an air cylinder, a hydraulic cylinder, etc.) (left-right direction in FIG. 1). Displaceable. The first movable mold 51 and the second movable mold 52 are attached to the second mold 50 so as to be displaceable, for example. Further, the displacement direction of the first movable mold 51 and the second movable mold 52 is set along the mold closing direction (and mold opening direction) of the first mold 30 and the second mold 50.

  Next, a method for manufacturing the molded structure 10 of the present embodiment will be described. The manufacturing method of the molded structure 10 in the present embodiment includes a press molding process in which the preboard P1 (base material 12 before molding) is press-molded with a pair of molding dies 21, and a through hole in which the through hole 13 is formed in the base material 12. A forming step, an injection step of injecting the molten resin into the cavity 31, and a movable type moving step of moving the first movable die 51 and the second movable die 52, respectively.

(Press molding process)
In the press molding process (base material molding process), as shown in FIG. 1, a pre-heated preboard P1 (base material 12 before molding) that has been heated in advance is opened with a first molding die 30 and a second molding. Set between molds 50. At this time, one surface 12A (the surface on which the molded body 15 is molded) of the preboard P1 is disposed so as to face the facing surface 30A of the first molding die 30, and the other surface 12B of the preboard P1 is opposed to the second molding die 50. The face 50A is disposed opposite to the face 50A. In addition, as a heating method of the pre-board P1, for example, blowing hot air or irradiating infrared rays can be exemplified.

  In addition, the second movable mold 52 is disposed so that the facing surface 52A of the base 12 is flush with the facing surface 50A of the second mold 50 (abutting surface that comes into contact with the preboard P1). . On the other hand, the first movable mold 51 is arranged behind the recess 55 (on the right side in FIG. 1) as compared with the second movable mold 52.

  Thereafter, as shown in FIG. 2, the first molding die 30 and the second molding die 50 are closed to press the preboard P <b> 1 by the first molding die 30 and the second molding die 50. Thus, the pre-board P1 is formed into a predetermined shape (product shape) by the first forming die 30 and the second forming die 50, and the base material 12 is formed.

  Moreover, the shape | molded base material 12 is distribute | arranged in the state which obstruct | occluded the opening of the cavity 31, as shown in FIG. Thereby, the cavity 31 is formed as a closed space by being blocked by the base material 12.

  The other surface 12B of the molded substrate 12 and the facing surface 52A of the second movable mold 52 are in contact with each other with no gap. On the other hand, a gap (first molding space S1) is formed between the other surface 12B of the substrate 12 and the facing surface 51A of the first movable mold 51.

(Through hole forming process)
In the through-hole forming step, the blade 34 is driven in a state where the substrate 12 is pressed by the first mold 30 and the second mold 50, and is displaced from the inside of the housing recess 33 toward the cavity 31 side. As a result, as shown in FIG. 3, the blade 34 penetrates the base material 12, and the tip thereof reaches the first molding space S <b> 1, thereby forming the through hole 13 in the base material 12. Thereby, the cavity 31 and the first molding space S1 are communicated with each other through the through hole 13. Then, after forming the through hole 13, the blade 34 is accommodated in the accommodating recess 33.

(Injection process)
In the injection process, as shown in FIG. 4, molten resin is injected into the cavity 31 through the resin supply path 32 by the injection device 25. As a result, the molten resin 27 is filled into the cavity 31.

  Further, a part of the molten resin injected into the cavity 31 passes through the through hole 13 (resin flow portion) of the base material 12 and flows into the first molding space S1 (the other surface 12B side of the base material 12). . In this injection step, the facing surface 52A of the second movable mold 52 facing the substrate 12 is in contact with the other surface 12B of the substrate 12 (the hole edge portion 13A of the through hole 13). Thereby, the situation where the circumference (hole edge part 13A) of penetration hole 13 changes with the pressure of the injected molten resin can be controlled.

(Movable movement process)
After the molten resin is filled in both the cavity 31 and the first molding space S1, the first movable mold 51 and the second movable mold 52 are driven. Specifically, as shown in FIG. 5, the first movable mold 51 is brought close to the other surface 12 </ b> B of the substrate 12. At the same time, the second movable mold 52 is moved away from the other surface 12B.

  By bringing the first movable mold 51 closer to the other surface 12B, the volume of the first molding space S1 is reduced. Further, by moving the second movable mold 52 away from the other surface 12B, a gap (second molding space communicating with the first molding space S1) is formed between the opposing surface 52A of the second movable mold 52 and the other surface 12B. S2) is formed. As a result, a part of the molten resin filled in the first molding space S1 is filled in the second molding space S2.

  Note that the sum of the volume of the first molding space S1 (see FIG. 5) and the volume of the second molding space S2 after the movable mold moving step is substantially equal to the volume of the first molding space S1 (see FIG. 4) in the injection step. It is supposed to be. Further, in the movable type moving step, as shown in FIG. 5, for example, the facing surface 51 </ b> A of the first movable mold 51 and the facing surface 52 </ b> A of the second movable mold 52 are arranged to be flush with each other.

  The molten resin filled in the cavity 31, the first molding space S1, and the second molding space S2 is mixed with the resin constituting the base material 12, and is united (mixed). Thereafter, the molten resin is cooled, and as shown in FIG. 5, the molded body 15, the inserted portion 16, and the locking portion 17 are molded in a state of being joined to the base material 12.

  Specifically, the molded body 15 and the locking portion 17 that are molded are arranged so as to cover each surface of the substrate 12. Further, the molded body 15 and the locking portion 17 are integrally connected through the inserted portion 16.

  Next, the effect of this embodiment will be described. In the present embodiment, after the molten resin is circulated in the first molding space S1, the volume of the first molding space S1 is reduced and the second molding space S2 is formed. Thereby, a part of the molten resin circulated in the first molding space S1 is supplied to the second molding space S2. That is, a part of the molten resin injected into the cavity 31 is supplied to the space (the first molding space S1 and the second molding space S2) on the base 12 opposite to the molding surface (one surface 12A) of the molded body 15. be able to.

  As a result, when the molten resin in the first molding space S1 and the second molding space S2 is hardened, the through hole 13 is formed on the other surface 12B (the surface opposite to the surface on which the molded body 15 is molded) of the substrate 12. A resin member (locking portion 17) connected to the molded body 15 is molded through the resin disposed on the surface. Thereby, the joining strength of the molded object 15 and the base material 12 can be made higher.

  Further, in the injection step, the molten resin is injected in a state where the second movable mold 52 is in contact with the periphery of the through hole 13 (hole edge portion 13A of the through hole 13) on the other surface 12B. If it does in this way, the situation where a part of substrate 12 (around penetration hole 13) changes with pressure of the injected molten resin can be controlled.

  In the movable mold moving step, the second movable mold 52 is moved to form the second molding space S2. Thereby, by filling molten resin into 2nd shaping | molding space S2, the area of the latching | locking part 17 can be enlarged more and the joining strength of the latching | locking part 17 and the base material 12 can be made high. .

  In the present embodiment, the resin circulation part can be easily formed by forming the through hole 13 in the base material 12. Moreover, by forming the through hole 13, the rigidity around the through hole 13 in the base 12 is relatively low. In the present embodiment, by bringing the second movable mold 52 into contact with the hole edge portion 13A of the through hole 13, a situation in which the hole edge portion 13A of the base material 12 is deformed by the pressure of the molten resin can be suppressed.

  The blade 34 has a shape in which the tip end is tapered. For this reason, as shown in FIG. 6, the tip of the blade 34 easily enters between the fibers 14 contained in the substrate 12. Thereby, the situation where the fiber contained in the base material 12 is cut by the blade 34 can be suppressed, and the strength of the base material 12 can be ensured.

<Other embodiments>
The present invention is not limited to the embodiments described with reference to the above description and drawings. For example, the following embodiments are also included in the technical scope of the present invention.

  (1) In the said embodiment, the seat back and door trim for vehicles were illustrated as a use of the base material 12, and the rib and the fastening member were illustrated as a use of the molded object 15, However, It is not limited to this. Applications of the base material 12 and the molded body 15 can be changed as appropriate.

  (2) The material of the base material 12 is not limited to what was illustrated by the said embodiment. Plant fibers such as kenaf may be used as the fibers contained in the substrate 12. Further, as the synthetic resin contained in the substrate 12, a thermosetting resin such as an epoxy resin may be used.

  (3) The material of the molded body 15 is not limited to that exemplified in the above embodiment. The molded body 15 may include fibers, for example. Further, if fibers are included in both the base material 12 and the molded body 15, or if the base material 12 and the molded body 15 are made of the same material, the linear expansion coefficients of the base material 12 and the molded body 15 can be increased. A closer value can be set. In this way, the difference in shrinkage during cooling of the base material 12 and the molded body 15 is reduced, and a situation in which stress is generated can be suppressed.

  (4) In the above-described embodiment, the through hole 13 is illustrated as the resin circulation part, but is not limited to the through hole 13. The resin flow part may be configured so that the molten resin can pass through. For example, by making the density of the base material 12 smaller than that of the surroundings, the inside of the base material 12 can be configured to allow the molten resin to pass through. It is good also as a distribution part.

  (5) The shapes of the molded body 15 and the base material 12 are not limited to those illustrated in the above embodiment, and can be changed as appropriate.

  (6) In the above embodiment, the method of forming the through hole 13 in the base material 12 after the press molding step is exemplified, but the present invention is not limited to this. The through holes 13 may be formed in the base material 12 before the press molding step (that is, before the base material 12 is set in the pair of molding dies 21). Further, the means for forming the through hole 13 is not limited to the blade 34.

  (7) The shape of the blade 34 is not limited to what was illustrated by the said embodiment, It can change suitably. For example, as shown in FIG. 7, a blade 134 that has an H shape in plan view and tapers may be used. Further, as shown in FIG. 8, for example, a blade 234 that has a cross shape in plan view and is tapered may be used. That is, the shape of the through hole formed in the base material 12 can be changed as appropriate. For example, as shown in FIGS. 7 and 8, a through hole 113 having an H shape in plan view and a through hole 213 having a cross shape in plan view can be exemplified.

  (8) In the movable mold moving step, after the second movable mold 52 is moved away from the other surface 12B, the first movable mold 51 may be moved closer to the other surface 12B.

DESCRIPTION OF SYMBOLS 10 ... Molding structure, 12 ... Base material, 12A ... One surface in a base material, 12B ... The other surface in a base material, 13 ... Through-hole (resin distribution part), 13A ... Periphery edge (around resin distribution part) ), 15 ... molded body, 30 ... first mold, 31 ... cavity (molded body molding space), 50 ... second mold, 51 ... first movable mold, 52 ... second movable mold, S1 ... first mold. Space, S2 ... Second molding space

Claims (2)

A substrate comprising a fiber and a synthetic resin and having a plate shape, and a molded body injection-molded on one surface of the substrate, and a method for producing a molded structure comprising:
A press-molding step of press-molding the base material with a first mold facing the one surface and a second mold facing the other surface of the base material;
Molding that is performed after the press molding step and is recessed in the first molding die in a state in which the base material is pressed by the first molding die and the second molding die to mold the compact. An injection process for injecting molten resin into the body molding space;
A movable mold moving step that is performed after the injection process and moves each of the first movable mold and the second movable mold provided in the second mold;
In the injection process,
With respect to the first molding space formed between the first movable mold and the other surface, the molten resin injected into the molding body molding space through the resin circulation portion formed on the base material While distributing a part,
The second movable mold is brought into contact with the periphery of the resin circulation portion on the other surface,
In the movable movement process,
Reducing the volume of the first molding space by bringing the first movable mold closer to the other surface;
A molding structure that forms a second molding space communicating with the first molding space between the second movable mold and the other surface by moving the second movable die away from the other surface. Manufacturing method. The resin flow part is a through hole formed through the base material,
2. The method for manufacturing a molded structure according to claim 1, wherein in the injection step, the second movable mold is brought into contact with a hole edge portion of the through hole on the other surface of the base material.

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