JP5803572B2 - Method for manufacturing molded structure - Google Patents

Description

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

  Conventionally, a molding structure used for a door trim or the like has a base material containing a thermoplastic resin, and the molded body (such as a bracket) is joined to the base material by injection molding the thermoplastic resin on the base material. (For example, Patent Document 1 below). According to the following Patent Document 1, the molten resin constituting the molded body is likely to permeate into the joint portion by reducing the density of the joint portion with the molded body in the base material. Thereby, the joint strength resulting from the anchor effect of a molded object and a junction part can be made high.

  Further, as shown in FIG. 5, the above-described molded body injects molten resin into the cavity C <b> 1 (molding space) formed in the molding die 1 with the base material 3 pressed into the molding die 1. Molded with. Further, when the base material 3 is pressed against the mold 1, the periphery of the joint 4 is in contact with the mold surface 1 </ b> A of the mold 1.

JP 2009-113244 A

  However, in the above configuration, when the molten resin is injected into the cavity C1, there is a concern that the molten resin reaches (leaks) around the joint portion 4 (the peripheral portion 5) in the base material 3 (FIG. 5). reference). This is because the molten resin intrudes into the slight gap between the base material 3 and the mold surface 1A in the peripheral portion 5, or because the joint portion 4 in the base material 3 has a low density, As a result, it is conceivable that the molten resin penetrates (appears) on the surface of the peripheral portion 5 through the inside of the base material 3 (near the surface).

  When the molten resin for forming the molded body 6 reaches the peripheral portion 5 of the joint portion 4 in the base material 3, the joint area between the base material 3 and the molded body 6 increases. As a result, when the injected molten resin (molded product) is cooled and contracted, as shown in FIG. 6, the surface 3A on the side opposite to the joint 4 in the base material 3 is uneven (the protrusion 3B is shown in FIG. 6). ) May occur, resulting in a decrease in design properties. Further, it is preferable that the strength of the periphery of the joint portion 4 with the molded body 6 in the base material 3 is high, and there is room for improvement in this respect as well.

  The present invention has been completed on the basis of the above circumstances, and suppresses a situation in which the molten resin reaches the periphery of the joint portion during molding of the molded body, thereby suppressing a decrease in design property and a base material. An object of the present invention is to provide a molded structure capable of increasing the strength around the joint with the molded body. Moreover, it aims at providing the manufacturing method of the molded structure which can manufacture such a molded structure.

  In order to solve the above problems, the molded structure of the present invention was molded in a state of being joined to the base material by injecting a molten resin onto the base material containing the thermoplastic resin and the base material. In the base material, the first peripheral portion positioned around the joint portion with the molded body is the second periphery positioned around the first peripheral portion. It is characterized by being a high-density part having a higher density than the part.

  According to the present invention, in the base material, the first peripheral portion located around the joint portion with the molded body is a high-density portion having a higher density than the second peripheral portion around the first peripheral portion. With such a configuration, when the molten resin is injected onto the base material (joining portion) to form a molded body, the first peripheral portion has the same density as the second peripheral portion, compared with the configuration in which the first peripheral portion has the same density. The molten resin does not easily penetrate into the first peripheral portion, and the molten resin does not ooze out on the surface of the first peripheral portion. That is, the situation where the molten resin reaches the periphery of the joint can be suppressed. Thereby, the situation where the joining area of a base material and a molded object increases can be suppressed, and the situation where an unevenness | corrugation arises on the opposite side to the junction part in a base material due to the thermal contraction of a molded object can be suppressed. Moreover, in this invention, the intensity | strength near a junction part can be made high by making the density of the 1st circumference part located in the circumference | surroundings of a junction part with a molded object high.

  The said structure WHEREIN: The density of the said base material shall become high gradually as it goes to the said 1st surrounding part from the said 2nd surrounding part.

  In general, if the density is partially different in the base material, the part is likely to be visually recognized in a mode different from other parts, and the designability may be impaired. Therefore, in the present invention, the density of the base material is gradually decreased from the second peripheral portion toward the first peripheral portion. With such a configuration, the boundary between the first peripheral portion and the second peripheral portion having different densities is less noticeable, and a situation in which the design property is impaired can be suppressed.

  Next, in order to solve the above-mentioned problem, a method for producing a molded structure according to the present invention is a molded structure including a base material including a thermoplastic resin and a molded body molded on the base material. A manufacturing method comprising: a base material forming step of forming the base material by press-molding a preboard with a forming die; and a cavity formed in the forming die in a state where the base material is pressed by the forming die. A molded body molding step in which the molded body is molded in a state where the molded body is bonded to the base material by injecting a molten resin into the base material. The first peripheral portion is formed by press molding so that the plate thickness of the first peripheral portion positioned around the joint portion is smaller than the plate thickness of the second peripheral portion positioned around the first peripheral portion. Making the density of the layer higher than the density of the second peripheral portion Having the features.

  According to the present invention, when molding a molded body by injecting molten resin into the cavity, the first peripheral portion is melted in the first peripheral portion as compared with the configuration in which the first peripheral portion has the same density as the second peripheral portion. The resin is difficult to penetrate. Further, when press molding is performed so that the thickness of the first peripheral portion is smaller than the thickness of the second peripheral portion by the molding die, the pressure acting on the first peripheral portion from the molding die is It tends to be larger than the pressure acting on the second peripheral portion. As a result, it is possible to suppress the occurrence of a gap between the mold and the first peripheral portion. For this reason, in the base material molding step, it is possible to more reliably suppress the situation where the molten resin enters between the mold and the first peripheral portion.

  From the above, in the present invention, it is possible to suppress the situation where the molten resin reaches the periphery of the joint. Thereby, the situation where the joining area of a base material and a molded object increases can be suppressed. As a result, it is possible to suppress the occurrence of unevenness on the opposite side of the base material from the joint portion due to the heat shrinkage of the molded body. Moreover, the intensity | strength near a junction part can be made high by making the density of the 1st circumference part located in the circumference | surroundings of a junction part with a molded object high.

  In the base material forming step, the base material may be formed such that the plate thickness gradually decreases from the second peripheral portion toward the first peripheral portion.

  In general, if the density is partially different in the base material, the part is likely to be visually recognized in a mode different from other parts, and the designability may be impaired. Therefore, in the present invention, the thickness of the base material is gradually reduced from the second peripheral portion toward the first peripheral portion. In such a configuration, in the configuration in which the density between the first peripheral portion and the second peripheral portion is changed by changing the plate thickness, the density is gradually increased from the second peripheral portion toward the first peripheral portion. Can be high. Thereby, the boundary of the 1st surrounding part and 2nd surrounding part from which a density differs becomes inconspicuous, and the situation which impairs design property can be suppressed.

  According to the present invention, it is possible to suppress the deterioration of the design property by suppressing the situation where the molten resin reaches the periphery of the joint at the time of molding the molded body, and to increase the strength of the periphery of the joint with the molded body in the base material. It is possible to provide a molded structure that can be used. Moreover, the manufacturing method of the molded structure which can manufacture such a molded structure can be provided.

Sectional drawing which shows the manufacturing method which manufactures the molded structure which concerns on Embodiment 1 of this invention, and a molded structure Sectional view showing base material molding process (before base material molding) Sectional view showing the base material molding process (after base material molding) Sectional drawing which shows the shaping | molding structure which concerns on Embodiment 2 of this invention. Sectional drawing which shows the manufacturing method which manufactures the conventional shaping | molding structure Sectional view showing a conventional molded structure

<Embodiment 1>
Embodiment 1 of the present invention will be described with reference to FIGS. The door trim 10 (molded structure) of this embodiment is attached to a vehicle door. As shown in FIG. 1, a bracket 30 (molded body) such as a clip seat is joined to a trim board 20 (base material). Is formed.

  The trim board 20 has a flat plate shape, and is constituted by impregnating polypropylene, which is a thermoplastic resin, into fibers. The trim board 20 is formed by compressing the mat-shaped preboard P1 (see FIG. 2) by pressing (thinning the plate thickness) to a higher density than the preboard P1. In addition, as a fiber used for the trim board 20, for example, a wood fiber obtained by weaving wood or the like, a bast plant fiber such as kenaf, or the like is used, but the type of the fiber is not limited thereto.

  In the trim board 20, polypropylene plays a role as a binder for connecting fibers. The trim board 20 may be formed of polypropylene or other thermoplastic resin alone, or may be formed of a mixture of a thermoplastic resin other than polypropylene such as polyethylene terephthalate and fibers.

  The bracket 30 is made of, for example, polypropylene, which is a thermoplastic resin, and is formed so as to protrude from the back surface (the surface on the vehicle interior side) of the trim board 20 as shown in FIG. The distal end wall portion 31 of the bracket 30 is bent in a shape substantially orthogonal to the proximal end wall portion 32. For example, a mounting hole (not shown) to which a clip (not shown) can be attached is formed in the tip wall portion 31, and the bracket 30 (trim board 20) is connected to the door inner panel via the clip. It is configured to be attached to (not shown).

  The bracket 30 is molded by injecting molten resin onto the trim board 20 with the trim board 20 set on the molding die 40A (details will be described later). That is, the bracket 30 is joined to the trim board 20 at the same time as molding.

  The joint portion 21 of the trim board 20 with the bracket 30 has a density (in this embodiment, the weight of the thermoplastic resin and fibers per unit volume) rather than the periphery of the joint portion 21 (first peripheral portion 22 described later). Is considered to be a low density part. This is because, when the preboard P1 is press-molded by the molding apparatus 40 described later, the joint portion 21 becomes a portion that is not compressed (or the degree of compression is small) by closing the upper die 41 and the lower die 42. .

  The low density portion is formed from the front surface to the back surface of the trim board 20 (in other words, substantially over the entire length in the plate thickness direction). In the trim board 20, the plate thickness t 2 of the first peripheral portion 22 positioned around the joint portion 21 is smaller than the plate thickness t 3 of the second peripheral portion 23 positioned around the first peripheral portion 22. Is done. That is, the first peripheral portion 22 is formed so as to surround the joint portion 21, and the second peripheral portion 23 is formed so as to surround the first peripheral portion 22. It can also be said that the second peripheral portion 23 is a portion disposed on the opposite side of the joint portion 21 with respect to the first peripheral portion 22.

  As shown in FIG. 2, the pre-board P1 before being formed on the trim board 20 has a uniform thickness t1 and density, for example, over the entire surface thereof. And the trim board 20 is shape | molded by press-molding this pre board P1. For this reason, the first peripheral portion 22 is a portion having a larger pressing amount than the second peripheral portion 23. Thus, the first peripheral portion 22 is a high-density portion having a higher density than the second peripheral portion 23.

  Further, the plate thickness t2 of the first peripheral portion 22 is, for example, 60% or less with respect to the plate thickness t1 of the pre-board P1. The plate thickness t3 of the second peripheral portion 23 is, for example, 90% or less with respect to the plate thickness t1 of the pre-board P1. Further, the plate thickness t2 is, for example, 60% or less with respect to the plate thickness t3. Note that the ratio (%) of the plate thicknesses t2 and t3 to the plate thickness t1 and the ratio (%) of the plate thickness t2 to the plate thickness t3 are not limited to the above-described values and can be changed as appropriate.

  Further, the thickness of the trim board 20 gradually decreases from the second peripheral portion 23 toward the first peripheral portion 22. More specifically, on the back surface 20B (molded surface of the bracket 30) of the trim board 20, the boundary portion between the first peripheral portion 22 and the second peripheral portion 23 is an inclined surface 20B1. For this reason, the density of the trim board 20 gradually increases (for example, linearly) from the second peripheral portion 23 toward the first peripheral portion 22. Moreover, the surface 20A (surface on the opposite side to the molding surface of the bracket 30) in the trim board 20 has, for example, a flat surface and is a surface on the design surface side.

  Next, the shaping | molding apparatus 40 which manufactures the door trim 10 is demonstrated. The molding apparatus 40 in the present embodiment is an injection molding apparatus, and includes a molding die 40A composed of an upper die 41 and a lower die 42, and an injection device 45.

  The injection device 45 is, for example, a screw type, and is provided in the lower die 42 in this embodiment. Inside the lower mold 42, a gate 48 through which the molten resin passes is routed. A bracket molding space S2 (cavity) for molding the bracket 30 is formed in the lower mold 42, and the gate 48 communicates with the bracket molding space S2. Accordingly, the molten resin can be injected from the injection device 45 into the bracket molding space S2 through the gate 48.

  The upper mold 41 is a movable mold that can move relative to the lower mold 42 by a driving device (not shown) (for example, an electric motor, an air cylinder, a hydraulic cylinder, or the like). The upper mold 41 can be closed and opened by moving the upper mold 41 close to and away from the lower mold 42. In the following description, the upper mold 41 and the lower mold 42 (molding mold 40A) shown in FIG. 1 are closed, and the upper mold 41 and the lower mold 42 shown in FIG. 2 are opened. It shall be called a state.

  As shown in FIG. 1, the lower mold 42 is disposed to face the upper mold 41 and the trim board 20 while being spaced apart from each other in the closed state. Thus, a base material forming space S1 for forming the trim board 20 is formed between the upper die 41 and the lower die 42. Accordingly, when the preboard P1 is pressed by the upper mold 41 and the lower mold 42, the preboard P1 is compressed in a shape corresponding to the shape of the base material forming space S1, and as a result, the trim board 20 is molded. Further, the bracket forming space S <b> 2 described above communicates with the base material forming space S <b> 1, and the communicating portion corresponds to the joint portion 21 in the trim board 20.

  A projecting portion 50 that projects toward the upper mold 41 is formed on a surface 42A of the lower mold 42 facing the upper mold 41. The protrusion 50 is for forming the first peripheral portion 22 (a portion having a smaller thickness and higher density than the second peripheral portion 23) in the trim board 20. At the tip of the protrusion 50, the base material forming space S1 and the bracket forming space S2 are communicated with each other. Further, the protrusion 50 has a substantially trapezoidal shape in a cross-sectional view, and has a shape in which the protrusion amount increases toward the center.

  Further, as shown in FIG. 1, a part of the lower mold 42 is a slide mold 43 that is slidable relative to a main body portion 47 of the lower mold 42 (a portion other than the slide mold 43 in the lower mold 42). When the slide mold 43 is slid by a drive device (not shown), it is possible to perform die cutting of the distal end wall portion 31 that is an undercut portion in the bracket 30. Further, the slide mold 43 constitutes a part of the bracket molding space S2 and a part of the protrusion 50 described above. The configuration of the slide mold 43 is not limited to that shown in FIG. 1 and can be changed as appropriate.

  Next, a method for manufacturing the door trim 10 using the molding apparatus 40 will be described with reference to the drawings of FIGS. The manufacturing method of the door trim 10 in the present embodiment includes a preboard molding process for molding the preboard P1, a base material molding process for molding the trim board 20 from the preboard P1, and a molded body molding process for molding the bracket 30 on the trim board 20. It is equipped with.

<Preboard molding process>
In the preboard molding process, the mat material mixed with fiber and polypropylene is heated and press-molded, and this is cut into a predetermined length (for example, a dimension longer than the length dimension of the trim board 20 after molding). The preboard P1 is formed by the above. Note that the preboard P1 is heated immediately after molding, and the polypropylene inside is softened.

<Base material forming process>
First, as shown in FIG. 2, the preboard P1 molded by the preboard molding process is heated again to such an extent that the polypropylene is melted and softened, and set to the lower mold 42 in the open state. Thereafter, as shown in FIG. 3, the upper mold 41 and the lower mold 42 are closed. Thereby, the preboard P1 is press-molded by the molding die 40A, and the trim board 20 is molded. In addition, when the mold is closed, an operation (not shown) of cutting the peripheral end portion of the pre-board P1 by shearing both molds 41 and 42 may be performed.

  At the time of press molding, the portion of the preboard P1 that faces the bracket molding space S2 is not compressed by the molding die 40A (or the compression amount is smaller than other portions), and therefore is relatively raised from the surroundings (thickness). Is a large state). This raised portion becomes a joint portion 21 with the bracket 30 in the trim board 20.

  Further, in the present embodiment, the protruding portion 50 is formed on the lower mold 42. For this reason, in the trim board 20, the location facing the protruding portion 50 (around the joint portion 21, the first surrounding portion 22) is compared with the location facing the periphery of the protruding portion 50 (the second surrounding portion 23). It press-molds so that the plate | board thickness may become small. Thereby, the density of the first peripheral portion 22 is higher than the density of the second peripheral portion 23. That is, the first peripheral portion 22 is a high density portion. Moreover, the density of the junction part 21 shall be lower than the 2nd surrounding part 23, for example.

  Further, since the protruding portion 50 has a shape in which the protruding amount increases toward the center thereof, the thickness of the trim board 20 gradually decreases from the second peripheral portion 23 toward the first peripheral portion 22. (Slowly changing shape).

<Molded body forming process>
Next, in a state where the trim board 20 is pressed by the molding die 40A, the molten resin is injected into the bracket molding space S2 through the gate 48 by the injection device 45. At this time, the temperature of the trim board 20 is set to a temperature at which the polypropylene inside the trim board 20 is softened. The injected molten resin penetrates into the inside of the fiber in place of the softened polypropylene while pushing the softened polypropylene inside the trim board 20 downward at the joint 21.

  At the same time, the molten resin that has penetrated into the fiber mixes with the softened polypropylene inside the trim board 20 and becomes a unitary (mixed). In this way, the bracket molding space S2 is filled with the molten resin, and then the molten resin is cooled, so that the bracket 30 is molded in a state of being joined to the trim board 20 as shown in FIG. Thereafter, by opening both molds 41 and 42 and moving the slide mold 43, the trim board 20 molded in a state where the bracket 30 is integrally joined can be removed, and the door trim 10 can be manufactured. Complete.

  In the present embodiment, the joining portion 21 is a location having a relatively low density. For this reason, the molten resin injected into the bracket molding space S2 easily penetrates into the inside of the joint portion 21 (for example, between the fibers constituting the joint portion 21). Thereby, the joint strength resulting from the anchor effect can be increased. Moreover, since the injected molten resin is mixed with the softened polypropylene inside the trim board 20, the bonding strength due to the welding effect can be increased.

  Next, the effect of this embodiment will be described. The door trim 10 of the present embodiment includes a trim board 20 including a thermoplastic resin, and a bracket 30 molded in a state of being joined to the trim board 20 by injecting a molten resin onto the trim board 20. In the trim trim 20, the first peripheral portion 22 located around the joint portion 21 with the bracket 30 in the trim board 20 has a density higher than that of the second peripheral portion 23 located around the first peripheral portion 22. Is a high density part.

  According to this embodiment, the 1st surrounding part 22 located in the circumference | surroundings of the junction part 21 with the bracket 30 is made into a high-density part whose density is higher than the 2nd surrounding part 23 of the circumference | surroundings. With such a configuration, the first peripheral portion 22 has the same density as the second peripheral portion 23 when the bracket 30 is formed by injecting molten resin onto the trim board 20 (joint portion 21). In comparison with the first peripheral portion 22, the molten resin is less likely to permeate, and the molten resin does not ooze out (appear) on the surface of the first peripheral portion 22.

  That is, the situation where the molten resin reaches the periphery of the joint portion 21 can be suppressed. Thereby, the situation where the joining area of the trim board 20 and the bracket 30 increases can be suppressed, and the situation where unevenness is generated on the opposite side of the trim board 20 from the joining portion 21 due to the thermal contraction of the bracket 30 can be suppressed. Moreover, in this embodiment, the intensity | strength of the junction part 21 vicinity can be made high by making the density of the 1st surrounding part 22 located in the circumference | surroundings of the junction part 21 with the bracket 30 high.

  Even if the entire surface of the trim board 20 has the same density (thickness) as that of the first peripheral portion 22 (high density portion), the above-described effect (prevention of molten resin permeation into the first peripheral portion 22) can be achieved. Is possible. However, if the entire surface of the trim board 20 is a high density portion, the thickness of the entire surface of the trim board 20 is reduced, and as a result, the trim board 20 is easily bent (stiffness is reduced). For this reason, in the present embodiment, only the first peripheral portion 22 that is the periphery of the joint portion 21 (that is, the portion where the molten resin may permeate when the bracket 30 is molded) is a relatively dense portion. . Thereby, the trim board 20 can be made difficult to bend while having a configuration in which the design property and the strength in the vicinity of the joint portion 21 are increased.

  Moreover, the manufacturing method of the door trim 10 of this embodiment is a manufacturing method of the door trim 10 provided with the trim board 20 containing a fiber and a thermoplastic resin, and the bracket 30 shape | molded on the trim board 20, Comprising: In the bracket forming space S2 formed in the forming die 40A in a state in which the trim board 30 is pressed by the forming die 40A and the base material forming step of forming the trim board 30 by pressing the P1 with the forming die 40A. A molded body molding step of molding the bracket 30 in a state of being joined to the trim board 20 by injecting molten resin, and in the base material molding step, the periphery of the joint portion 21 with the bracket 30 in the trim board 20 The plate thickness t2 of the first peripheral portion 22 located at the position is equal to the plate thickness t3 of the second peripheral portion 23 located around the first peripheral portion 22. By also press molding so as to reduce, with the features of the density of the first peripheral portion 22 to be higher than the density of the second peripheral portion 23.

  According to the manufacturing method of the present embodiment, when molding the bracket 30 by injecting molten resin into the bracket molding space S <b> 2, the first peripheral portion 22 is compared with the configuration having the same density as the second peripheral portion 23. Thus, it is difficult for the molten resin to penetrate into the first peripheral portion 22. Further, when the molding die 40A is press-molded so that the plate thickness t2 of the first peripheral portion 22 is smaller than the plate thickness t3 of the second peripheral portion 23, the first peripheral portion 22 ( The pressure acting on the lower die 42) tends to be larger than the pressure acting on the second peripheral portion 23 from the molding die 40A (lower die 42). That is, the trim board 20 is pressed with a stronger force at the portion where the protrusion 50 is formed. As a result, it is possible to suppress the occurrence of a gap between the lower mold 42 (projecting part 50) and the first peripheral part 22. For this reason, in the base material molding step, it is possible to more reliably suppress the situation where the molten resin enters between the molding die 40A (lower die 42) and the first peripheral portion 22.

  From the above, in the present embodiment, in the trim board 20, it is possible to suppress the situation where the molten resin reaches the periphery of the joint portion 21. Thereby, the situation where the joining area of the trim board 20 and the bracket 30 increases can be suppressed. As a result, it is possible to suppress the occurrence of unevenness on the opposite side of the trim board 20 from the joint portion 21 due to the thermal contraction of the bracket 30. Moreover, the intensity | strength of the junction part 21 vicinity can be made high by making the density of the 1st surrounding part 22 located in the circumference | surroundings of the junction part 21 with the bracket 30 high. Further, the density of the first peripheral portion 22 can be relatively increased by press molding so that the plate thickness t2 of the first peripheral portion 22 is smaller than the plate thickness t3 of the second peripheral portion 23. The high density portion can be easily formed.

  In addition, the trim board 20 may have a plate shape, and the thickness of the trim board 20 may gradually decrease from the second peripheral portion 23 toward the first peripheral portion 22.

  In general, if the density is partially different in the trim board 20, the part is likely to be visually recognized in a manner different from other parts, and the designability may be impaired. Therefore, in the present embodiment, the trim board 20 is configured such that the thickness of the trim board 20 gradually decreases from the second peripheral portion 23 toward the first peripheral portion 22. In such a configuration, in the configuration in which the density of the first peripheral portion 22 and the second peripheral portion 23 is changed by changing the plate thickness, as it goes from the second peripheral portion 23 to the first peripheral portion 22, The density can be increased little by little. Thereby, the boundary of the 1st surrounding part 22 and the 2nd surrounding part 23 from which a density differs becomes inconspicuous, and the situation which impairs designability can be suppressed.

<Embodiment 2>
A second embodiment of the present invention will be described with reference to FIG. The same parts as those in the above embodiment are denoted by the same reference numerals, and redundant description is omitted. In the present embodiment, the configurations of the lower mold 142 and the trim board 120 are different from those of the above embodiment.

  A second protrusion 151 protruding toward the upper mold 41 is formed on the protrusion 150 (first protrusion) of the lower mold 142. The second projecting portion 151 is formed around the bracket molding space S2. Thus, in the base material forming step, the preboard P1 is pressed to the second projecting portion 151, whereby the groove portion 124 is formed around the joint portion 21 in the trim board 20.

  With such a configuration, in the base material forming step, the preboard P1 is further compressed by the amount of the second protruding portion 151 as compared with a configuration that does not have the second protruding portion 151. As a result, the density in the vicinity of the groove 124 in the first peripheral portion 22 of the trim board 20 can be further increased. Moreover, by providing the 2nd protrusion part 151, the situation where the clearance gap between the 2nd protrusion part 151 and the trim board 20 can be suppressed, and the situation where molten resin penetrate | invades into the 1st circumference part 22 can be suppressed.

  Moreover, in this embodiment, the shape of the protrusion part 150 in the lower mold | type 142 and the formation location of bracket shaping | molding space S2 differ from the said embodiment. In the present embodiment, the protrusion 150 has a symmetrical shape in the extending direction of the trim board 120 (the left-right direction in FIG. 4). The bracket forming space S <b> 2 is formed near the center of the protruding portion 150 in the extending direction of the trim board 120. That is, the shape of the protruding portion and the location where the bracket forming space S2 is formed are not limited to those exemplified in the above embodiment, and can be changed as appropriate.

<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 above embodiment, the door trim 10 is exemplified as the molded structure, the trim board 20 is exemplified as the base material, and the bracket 30 is exemplified as the molded article. However, the present invention is not limited thereto. As a molded structure, it is possible to mold a molded body by injection molding a molten resin to a base material containing a thermoplastic resin such as a backboard of a sheet, and at the same time melt and bond the base material and the molded body It may be molded.

  (2) In the above embodiment, a plurality of brackets 30 may be attached to the trim board 20.

  (3) In the above embodiment, the protrusion 50 in the mold 40A has a substantially trapezoidal shape in cross-section, but the present invention is not limited to this. The protrusion part 50 should just be a shape which can form the 1st surrounding part 22 by compressing the preboard P1 partly strongly, and the shape can be changed suitably.

  (4) In the above embodiment, the first peripheral portion 22 may be configured not to surround the entire circumference of the joint portion 21. Further, the second peripheral portion 23 may be configured not to surround the entire circumference of the first peripheral portion 22.

  (5) In the above-described embodiment, the preboard P1 has a uniform thickness and density over the entire surface. However, the present invention is not limited to this. Regardless of the thickness and density of the preboard P1, as a result of molding the trim board 20 by press molding the preboard P1, the density of the first peripheral portion 22 is higher than the density of the second peripheral portion 23. That's fine. In the trim board 20, the first peripheral portion 22 and the second peripheral portion 23 may have substantially the same thickness.

  (6) In the above embodiment, the configuration in which the thickness (and consequently the density) of the trim board 20 gradually decreases from the second peripheral portion 23 toward the first peripheral portion 22 is exemplified, but the present invention is not limited to this. The thickness (and hence the density) of the first peripheral portion 22 may be abruptly smaller than the thickness of the surrounding portion (second peripheral portion 23).

  (7) The materials of the trim board 20 and the bracket 30 are not limited to those exemplified in the above embodiment, and can be changed as appropriate.

DESCRIPTION OF SYMBOLS 10 ... Door trim (molding structure), 20,120 ... Trim board (base material), 21 ... Joining part, 22 ... 1st surrounding part, 23 ... 2nd surrounding part, 30 ... Bracket (molding body), 40A ... Molding Mold, P1 ... Pre-board, S2 ... Bracket molding space (cavity), t2 ... Plate thickness of first peripheral portion, t3 ... Plate thickness of second peripheral portion

Claims (2)

A base material constituted by impregnating a fiber material with a thermoplastic resin, and a molded body formed on the base material, and a method for producing a molded structure comprising:
A base material molding step of molding the base material by press molding a preboard with a mold;
In a state where the base is pressed by the mold, a molten resin is injected into a cavity formed in the mold so that the molded body is bonded to the base at a portion where the molded body is joined. Molded body molding for pressing the softened thermoplastic resin and molding the molded body in a state where the molten resin penetrates into the inside of the fiber material instead of the thermoplastic resin. A process,
In the base material forming step, the plate thickness of the first peripheral portion located around the joint portion with the molded body in the base material and surrounding the joint portion is located around the first peripheral portion. The density of the first peripheral part is made higher than the density of the second peripheral part by press molding so as to be smaller than the plate thickness of the second peripheral part , and
A molding structure characterized by press-molding such that a width dimension of the first peripheral portion in the direction of the plate surface of the base material and the direction of alignment with the molded body is larger than the plate thickness of the first peripheral portion. Manufacturing method. In the base material molding step,
2. The method for producing a molded structure according to claim 1, wherein the base material is molded such that the plate thickness gradually decreases from the second peripheral portion toward the first peripheral portion.

Images