JP7334062B2 - Resin molded article and its manufacturing method - Google Patents

Description

The present invention relates to a resin molded product having an integral hinge and a method for manufacturing the resin molded product.

For example, as shown in Patent Literature 1, two mounting plates connected via a thin integral hinge are molded in an unfolded state and bent at the integral hinge so that the two mounting plates face each other. Vehicle side mudguards have been proposed that are positioned to

Japanese Patent No. 4798617

The aforementioned side mudguard has the problem that the strength of the integral hinge is weakened because the integral hinge is formed thinner than the mounting plate.

SUMMARY OF THE INVENTION The present invention has been proposed in view of the above-mentioned problems associated with the prior art, and has been proposed to preferably solve these problems. intended to provide

In order to overcome the above problems and achieve the intended purpose, the resin molded product according to the present invention is
a panel;
an integral hinge that is integrally formed with the panel so as to be thinner than the panel and connects the two panels so that their relative postures can be changed;
The gist of the invention is that the hinge reinforcing region set in at least a part of the integral hinge is formed with a higher density than the panel over the entire alignment direction of the two panels connected by the integral hinge. do.

In order to overcome the above problems and achieve the intended purpose, the method for producing a resin molded product according to the present invention comprises:
When molding a resin molded product with an integral hinge that is integrally formed with the panel so as to be thinner than the panel and connects the two panels so that the relative posture can be changed,
setting a variable space corresponding to a hinge reinforcing region set in at least a partial range of the integral hinge in the cavity of the mold to be wider than the plate thickness of the integral hinge to be obtained;
Filling the cavity with a resin raw material,
The mold surface defining the variable space in the molding die is moved so as to narrow the variable space, and the resin raw material filled in the variable space is compressed, so that the hinge reinforcing region is replaced by the Integral The gist of the invention is to make the density higher than that of the two panels connected by the hinge over the entire alignment direction of the panels.

According to the resin molded product of the present invention, the strength of the integral hinge can be improved.
According to the method for manufacturing a resin molded product according to the present invention, the strength of the integral hinge can be improved.

1 is a schematic perspective view showing a side mudguard according to an embodiment of the invention; FIG. In addition, it is in the forming posture. It is a front view seen from the inner surface side of the side mudguard of the embodiment. In addition, it is in the forming posture. 2. (a) is a sectional view taken along line AA of FIG. 2, and (b) is a sectional view taken along line BB of FIG. (a) is a cross-sectional view of the side mudguard in the use posture cut at a position corresponding to line AA in FIG. 2, and (b) is a side mudguard in the use posture corresponding to line BB in FIG. It is a cross-sectional view cut at a position to be. It is a C section enlarged view of Fig.3 (a). In addition, the part with high density is darkly shown. It is explanatory drawing which shows the manufacturing process of the side mudguard of an Example. It is explanatory drawing which shows the manufacturing process of the side mudguard of an Example. (a) shows the state before compression of the resin material in the variable space, and (b) shows the state of compression of the resin material in the variable space. In addition, in (b), a portion with a high density is shown dark. FIG. 4 is an explanatory diagram of a main part showing the manufacturing process of the side mudguard of the embodiment; (a) shows the resin raw material before compression, and (b) shows the resin raw material in a compressed state. In addition, in (b), a portion with a high density is shown dark. It is explanatory drawing which shows the manufacturing process of the side mudguard of an Example.

BEST MODE FOR CARRYING OUT THE INVENTION Next, the resin molded product and the method for manufacturing the resin molded product according to the present invention will be described below with reference to preferred embodiments and with reference to the accompanying drawings. In the embodiments, a side mudguard, which is an aeropart that is attached to a lower portion of a door between the front and rear wheels of a vehicle, will be described as an example of a resin molded product.

As shown in FIG. 1, a side mudguard (resin molded product) 10 includes plate-like panels 12 and 14 and an integral hinge 16 connecting the two panels 12 and 14 together. The side mudguard 10 is configured to be bent by an integral hinge 16 so that the relative posture of the two panels 12 and 14 can be changed. Specifically, the side mudguard 10 is molded in a posture in which the two panels 12 and 14 are unfolded (molding posture, see FIGS. 1 to 3). It can be changed to a posture (use posture, see FIG. 4) in which the panels 12 and 14 are arranged facing each other. The side mudguard 10 is installed on the vehicle body in the use posture. Of the two panels in the side mudguard 10, the inner panel 12 is the inner panel when installed on the vehicle body, and the outer panel 14 is the outer panel when installed on the vehicle body. In addition, in the plate surface of the side mudguard 10, the surface that is the outside in the use posture is called the outer surface, and the surfaces that face both panels 12 and 14 in the use posture are called the inner surfaces.

As shown in FIG. 3 , the side mudguard 10 in the molded posture is formed such that the inner panel 12 extends vertically, and an integral hinge 16 is provided over the entire upper edge of the inner panel 12 . The outer panel 14 is formed such that the lower portion thereof is curved inwardly with respect to the upper portion extending in the vertical direction, and is connected to the integral hinge 16 over the entire lower edge. In the side mudguard 10 in the molded posture, the integral hinge 16 is provided at a curved portion that switches from the vertically extending inner panel 12 to the lower portion of the outer panel 14 extending inwardly and outwardly of the inner panel 12 (lateral direction in the vehicle). ing. As shown in FIG. 4, the side mudguard 10 has an inner panel 12 and an upper portion of the outer panel 14 facing each other in the use posture, starting from the integral hinge 16, and forming a "U" shape with the lower portion of the outer panel 14 as the bottom. shape.

As shown in FIGS. 1 and 3-5, the integral hinge 16 is integrally formed with the inner panel 12 and the outer panel 14 so as to be thinner than the inner panel 12 and the outer panel 14. As shown in FIGS. The integral hinge 16 is formed so as to be recessed from the inner surface (one surface) side of the side mudguard 10 . The plate thickness of the integral hinge 16 is the thinnest in the integral hinge 16 at the bent portion where the extension lines of the outer surface of the inner panel 12 and the outer surface of the outer panel 14 of the side mudguard 10 intersect. That is, in the embodiment, the bent portion is set as a deformation starting point 16a at which the integral hinge 16 is easily bent. For example, the plate thickness of the inner panel 12 and the outer panel 14 is set to about 2.5 mm, while the plate thickness of the deformation starting point 16a is set to about 0.8 mm.

As shown in FIG. 2 , the side mudguard 10 has a hinge reinforcing region 18 set on at least a portion of the integral hinge 16 . The hinge reinforcing region 18 is formed with a higher density than the inner panel 12 and the outer panel 14 over the entire alignment direction of the two panels 12 and 14 connected by the integral hinge 16 (hereinafter simply referred to as alignment direction). there is In addition, in FIG. 2, the hinge reinforcement area|region 18 is shaded and shown. The hinge reinforcing region 18 of the embodiment is provided in a partial range of the integral hinge 16 in the direction in which the integral hinge 16 extends (the longitudinal direction of the vehicle). Thus, the integral hinge 16 comprises a plurality of hinge reinforcing regions 18 spaced apart from each other. The integral hinge 16 has a higher density than the panels 12 and 14 in the entire portion thinner than the panels 12 and 14 in the hinge reinforcing region 18, and the panel 12 in the region (non-reinforced region) that is not the hinge reinforcing region 18. , 14. In the integral hinge 16, the high-density hinge reinforced region 18 has higher mechanical properties than the non-reinforced region. In the integral hinge 16, although the density of the hinge reinforced area 18 and the non-reinforced area is different, the board thickness of the hinge reinforced area 18 and the non-reinforced area is the same.

As shown in FIGS. 1-3, at least one of the two panels 12, 14 connected by the integral hinge 16 extends from the edge of the panel 12, 14 opposite the integral hinge 16 toward the hinge reinforcing region 18. It is provided with bulging portions 20 and 22 formed so that the inner surface (one surface) side bulges as it goes along. The side mudguard 10 of the embodiment has an inner bulging portion (bulging portion) 20 formed on the inner surface side of the inner panel 12 and an outer bulging portion (bulging portion) 22 formed on the inner surface side of the outer panel 14. and The inner bulging portion 20 and the outer bulging portion 22 are arranged side by side in the alignment direction with the hinge reinforcing region 18 interposed therebetween. Note that the side mudguard 10 does not have a shape in which the outer surfaces of the inner panel 12 and the outer panel 14 are uneven corresponding to the bulging portions 20 and 22 .

As shown in FIG. 2 , the inner bulging portion 20 is provided on the inner panel 12 from the edge opposite to the integral hinge 16 (the lower edge in the molding posture) to the hinge reinforcing region 18 . In addition, as shown in FIG. 3 , the inner bulge portion 20 is formed so that the bulge increases from the lower edge toward the hinge reinforcing region 18 . Furthermore, the inner bulging portion 20 of the embodiment is formed so that the width in the direction in which the integral hinge 16 extends (the longitudinal direction in the vehicle) increases from the lower edge toward the hinge reinforcing region 18 (see FIG. 2). reference). A portion of the inner panel 12 provided with the inner bulging portion 20 is thicker than a portion not provided with the inner bulging portion 20, and the inner bulging portion 20 pushes the inner panel 12 closer to the integral hinge 16 than to the lower edge side. plate thickness is increased.

As shown in FIG. 1 , the outer bulging portion 22 is provided on the outer panel 14 from the hinge reinforcing region 18 to a midway position toward the edge (upper edge) opposite to the integral hinge 16 . In the embodiment, an outer bulging portion 22 is formed in the lower portion of the outer panel 14 extending in the inward and outward directions (lateral direction in the vehicle). Further, the outer bulge portion 22 is formed so that the bulge becomes smaller from the hinge reinforcing region 18 toward the upper edge side of the outer panel 14 . Furthermore, the outer bulging portion 22 is formed to have the same width in the direction in which the integral hinge 16 extends (front-to-rear direction in the vehicle) throughout from the hinge reinforcing region 18 toward the upper edge side of the outer panel 14 . The portion of the outer panel 14 where the outer bulging portion 22 is provided is thicker than the portion where the outer bulging portion 22 is not provided. plate thickness is thicker.

As shown in FIGS. 6 to 9, the side mudguard 10 described above can be obtained by injection molding using a mold 30 in which a cavity 36 is formed between a first mold portion 32 and a second mold portion 34. can. A cavity 36 is formed in the molding die 30 so as to match the side mudguard 10 in the molding posture. It is designed to The first mold portion 32 is provided with a block 38 that corresponds to the hinge reinforcing region 18 of the integral hinge 16 and is configured to be movable forward and backward with respect to the mold surface of the second mold portion 34 that faces it. The block 38 is in an expanded state (see FIGS. 7(a) and 8(a)) in which the block 38 is separated from the mold surface of the second mold portion 34 by more than the plate thickness of the integral hinge 16 to be obtained, and the integral hinge 16 to be obtained. 7(b) and 8(b). Therefore, the space corresponding to the hinge reinforcing region 18 in the cavity 36 is a variable space 36a that expands or contracts according to the movement of the block 38. As shown in FIG. Note that the block 38 can be operated in conjunction with, for example, an existing ejection mechanism. 6 to 9 show the orientation with the inner panel 12 side facing downward, but the orientation of the side mudguard 10 during molding is not limited to this.

As shown in FIGS. 6 and 7, the molding die 30 has a gate 40 at a position corresponding to the lower edge of the inner panel 12 in the molding posture. In other words, the variable space 36a of the cavity 36 and the gate 40 connected to the position corresponding to the edge of one of the two panels 12, 14 connected by the integral hinge 16 on the opposite side of the integral hinge 16 are divided into two The two panels 12 and 14 are arranged side by side. In the mold 30, the resin raw material R (see FIG. 7) supplied from the gate 40 to the cavity 36 passes from the portion corresponding to the inner panel 12 to the portion corresponding to the integral hinge 16, and then to the outer panel 14. The site is filled. A portion (variable space 36a) of the cavity 36 that becomes the hinge reinforcing region 18 is arranged on the opposite side of the gate 40 across the portion that becomes the inner panel 12. The gate 40 corresponds to the plurality of hinge reinforcing regions 18. are placed multiple times.

As shown in FIG. 6 , the first mold portion 32 includes an inner recessed portion 32 a forming the inner bulging portion 20 and an outer recessed portion 32 b forming the outer bulging portion 22 . A portion of the cavity 36 corresponding to the inner panel 12 widens between the first mold portion 32 and the second mold portion 34 from the gate 40 toward the variable space 36a due to the inner recess 32a. At a portion of the cavity 36 corresponding to the outer panel 14, the space between the first mold portion 32 and the second mold portion 34 on the variable space 36a side is widened by the outer concave portion 32b. Thus, in the mold 30, the portion of the cavity 36 extending from the gate 40 toward the variable space 36a and the periphery of the variable space 36a are formed widely by the inner recess 32a and the outer recess 32b.

Next, a method of manufacturing the side mudguard 10 using the mold 30 described above will be described. As shown in FIG. 6, before supplying the resin raw material R, the block 38 is in an expanded state, so that the hinge reinforcing region 18 set in at least a part of the integral hinge 16 in the cavity 36 of the mold 30 is expanded. is set wider than the plate thickness of the integral hinge 16 to be obtained. While the block 38 is in the expanded state, the resin raw material R is supplied from the gate 40 to the cavity 36 while applying pressure, and the entire cavity 36 including the variable space 36a in the expanded state is filled with the resin raw material R (FIG. 7). (a) and FIG. 8(a)). After the resin raw material R is sufficiently filled and the flow of the resin raw material R is stopped in the cavity 36, the block 38 that partitions the variable space 36a in the mold 30 is moved to the variable space 36a while maintaining the pressure applied to the resin raw material R. to compress the resin raw material R filled in the variable space 36a (see FIGS. 7(b) and 8(b)). This increases the density of the resin raw material R filled in the variable space 36a. The variable space 36a expands beyond the plate thickness of the panels 12 and 14 when the block 38 is expanded, and is reduced to the plate thickness of the integral hinge 16 when the block 38 is compressed.

After solidifying the resin raw material R and molding the side mudguard 10, the mold 30 is opened (see FIG. 9) and the side mudguard 10 is taken out. In the resulting side mudguard 10, the hinge reinforcement area 18 of the integral hinge 16 corresponding to the variable space 36a is denser than both panels 12, 14 throughout the alignment direction.

Since the side mudguard 10 has the integral hinge 16 with the hinge reinforcing region 18 having a density higher than that of the panels 12 and 14, the mechanical properties such as the strength of the integral hinge 16 when used in a folded state are improved. . In the side mudguard 10, the hinge reinforcing region 18 is formed not only at the deformation starting point 16a where the thickness of the integral hinge 16 becomes thin, but also over the entire alignment direction of the integral hinge 16. As shown in FIG. Therefore, the hinge reinforcing region 18 can reinforce the entire portion to which stress is applied when the integral hinge 16 is bent. Further, the side mudguard 10 has a structure in which the hinge reinforcing region 18 is provided in a partial range of the integral hinge 16, so that the reinforcement of the integral hinge 16 and the ease of bending of the integral hinge 16 can be balanced. .

Since the integral hinge 16 is formed to be thinner than the inner panel 12 and the outer panel 14, the part corresponding to the integral hinge 16 in the cavity 36 becomes narrow, making it difficult for the resin raw material R to pass through. However, according to the manufacturing method of the side mudguard 10 described above, the variable space 36a corresponding to the reinforcing region 18 of the integral hinge 16 is made wider than the plate thickness of the integral hinge 16 to be obtained, and the cavity 36 is filled with resin. Raw material R is filled. Therefore, the resin raw material R can smoothly flow through the widened variable space 36a. As a result, poor flow of the resin raw material R between the portion corresponding to the inner panel 12 and the portion corresponding to the outer panel 14 in the cavity 36 can be prevented. Therefore, the resulting side mudguard 10 can be prevented from having appearance defects such as surface sink marks and weld lines or burrs caused by poor flow of the resin raw material R. In the manufacturing method, since the block 38 compresses the resin raw material R filled in the variable space 36a to form the integral hinge 16, the density of the hinge reinforcing region 18 corresponding to the variable space 36a can be easily increased. be able to. Thereby, the mechanical properties such as the strength of the obtained integral hinge 16 can be improved.

In the manufacturing method of the present disclosure, a plurality of variable spaces 36a and gates 40 are arranged side by side in the alignment direction. Therefore, the resin raw material R supplied from the gate 40 to the cavity 36 can smoothly flow to the portion corresponding to the outer panel 14 through the variable space 36a that is widened from the portion corresponding to the inner panel 12 . As a result, the resulting side mudguard 10 can be prevented from having appearance defects such as surface sink marks and weld lines or burrs due to poor flow of the resin raw material R. It should be noted that the gate 40 may be arranged at only one location depending on the size, shape, etc. of the side mudguard (resin molding) 10 . In this case, the variable space 36a may be arranged at only one place, or may be arranged at a plurality of places.

The cavity 36 is formed so as to widen in the direction corresponding to the plate thickness direction of the inner panel 12 as it goes from the gate 40 toward the variable space 36a by the inner recessed portion 32a. R easily flows. In addition, since the cavity 36 is widened around the portion corresponding to the integral hinge 16 by the variable space 36a, the inner recessed portion 32a and the outer recessed portion 32b, which are expanded by expanding the block 38, the gate 40 is provided. The resin raw material R easily flows from the portion corresponding to the inner panel 12 to the portion corresponding to the outer panel 14 . As a result, the resulting side mudguard 10 can be prevented from having appearance defects such as surface sink marks and weld lines or burrs due to poor flow of the resin raw material R.

(Change example)
The configuration is not limited to that described above, and may be modified as follows, for example.
(1) The object to which the present disclosure is applied is not limited to side mudguards, but may be other vehicle exterior members or may be applied to vehicle interior members. Moreover, it is applicable not only to parts for vehicles but also to general resin moldings having integral hinges.
(2) In the embodiment, a partial range in the direction in which the integral hinge extends is used as the hinge reinforcement area.
(3) In the embodiment, the resin molded product having one integral hinge was exemplified, but the resin molded product may have two or more integral hinges. Further, a configuration in which an integral hinge to which the present disclosure is applied and an integral hinge to which the present disclosure is not applied may be mixed.

10 side mudguard (resin molding), 12 inner panel (panel),
14 outer panel (panel), 16 integral hinge, 18 hinge reinforcing region,
20 inner bulging portion (bulging portion), 22 outer bulging portion (bulging portion), 30 mold,
36 cavities, 38 blocks, 40 gates

Claims (4)

a panel;
an integral hinge that is integrally formed with the panel so as to be thinner than the panel and connects the two panels so that their relative postures can be changed;
The hinge reinforcing region set in at least part of the integral hinge is formed with a higher density than the panel over the entire alignment direction of the two panels connected by the integral hinge ,
The hinge reinforcing region is provided only in a partial range of the integral hinge in the direction in which the integral hinge extends.
A resin molded product characterized by: a panel;
an integral hinge that is integrally formed with the panel so as to be thinner than the panel and connects the two panels so that their relative postures can be changed;
The hinge reinforcing region set in at least part of the integral hinge is formed with a higher density than the panel over the entire alignment direction of the two panels connected by the integral hinge,
The integral hinge is formed to be recessed from one surface of the panel,
The hinge reinforcing region is provided in a partial range of the integral hinge in a direction in which the integral hinge extends,
At least one of the two panels connected by the integral hinge is formed to bulge toward the one surface side from the edge of the panel opposite to the integral hinge toward the hinge reinforcing region. has a department
A resin molded product characterized by : One of the two panels connected by the integral hinge is formed with the bulging portion extending from the edge opposite to the integral hinge to the hinge reinforcing region,
3. The molded resin product according to claim 2, wherein the other of the two panels is formed with the bulging portion from the hinge reinforcing region to a midway position toward the edge on the side opposite to the integral hinge. When molding a resin molded product with an integral hinge that is integrally formed with the panel so as to be thinner than the panel and connects the two panels so that the relative posture can be changed,
setting a variable space corresponding to a hinge reinforcing region set in at least a partial range of the integral hinge in the cavity of the mold to be wider than the plate thickness of the integral hinge to be obtained;
A gate connected to a position corresponding to an edge of one of the two panels connected by the integral hinge opposite to the integral hinge, and the variable space are arranged in a direction in which the two panels are arranged. ,
filling resin raw material into the cavity from the gate ;
By moving the blocks defining the variable space in the mold so as to narrow the variable space and compressing the resin raw material filled in the variable space, the hinge reinforcing region is formed into the integral A method of manufacturing a resin molded product, wherein the density is higher than that of the two panels connected by a hinge over the entire alignment direction of the panels.

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