Resin molded product

Abstract

To provide a resin molded product whereby, in a process of molding a molded product having a hollow portion using a mold, it is possible to prevent problems such as contact between members forming the mold and dropping of the molded product when the mold is opened.SOLUTION: A resin molded product (1, 1a) of the present invention includes a hollow part (11) formed in the resin molded product (1, 1a) and at least one pressing surface that is pressed when the resin molded product (1, 1a) is released from a mold, and the hollow part (11) and the pressing surface are positioned so as to be spaced apart from each other in a direction intersecting a pressing direction against the pressing surface.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to a resin molded article obtained by molding a synthetic resin using a mold. [Background technology]

[0002] Japanese Patent Laid-Open Publication No. 54-93048 (Patent Document 1) describes a demolding method for releasing a molded product from a mold in a process for molding a cylindrical resin molded product having a hollow portion. In the demolding method of Patent Document 1, a stripper plate is installed between a female mold (movable mold) and a male mold (fixed mold), and after the molded product is ejected by the stripper plate, the stripper plate and the male mold are closed in a state in which the molded product and the stripper plate are eccentric with respect to the male mold, causing the molded product to fall and be demolded. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Publication No. 54-93048 Summary of the Invention [Problem to be solved by the invention]

[0004] For example, when releasing a molded product from a mold using the demolding method of Patent Document 1, there is a risk of problems such as the stripper plate coming into contact with the male mold (fixed mold) or the molded product falling, resulting in molding defects.

[0005] Furthermore, in the past, when a molded article having a hollow portion is molded using a mold, for example, when the mold is opened during the molding process to release the molded article, a method has been known in which the molded article is first held in a fixed or movable mold of the mold, and then an extrusion pin (also called an ejector pin) is brought into contact with the molded article to release the molded article.

[0006] However, in this case, there was a problem that the hollow forming member (e.g., slide piece) of the mold used to form the hollow part in the molded product came into contact with the ejector pin of the mold used to release the molded product. Also, when the mold was opened, the molded product would come off the fixed or movable mold and fall as the movable mold moved, which caused molding defects in the molded product.

[0007] The present invention has been made in consideration of the above-mentioned conventional problems, and its purpose is to provide a resin molded product that can prevent problems such as contact between the parts that form the mold and the molded product falling when the mold is opened during the process of molding a molded product having a hollow portion using a mold. [Means for solving the problem]

[0008] In order to achieve the above object, the resin molded product provided by the present invention is a resin molded product obtained by molding a synthetic resin using a mold, and the resin molded product has a hollow portion formed inside the resin molded product and at least one pressing surface that is pressed when the resin molded product is released from the mold, and the hollow portion and the pressing surface are set at positions spaced apart from each other in a direction intersecting the pressing direction of the pressing surface.

[0009] In the present invention, it is preferable that the resin molded product has a main body portion having the hollow portion and at least one protrusion portion protruding from the main body portion, and that the protrusion portion has the pressing surface and a holding portion extending from the pressing surface in a direction intersecting the opening and closing direction of the mold. Preferably, the protrusion has a guide shape that gradually reduces the protruding dimension from the main body in one direction. [Effects of the Invention]

[0010] According to the resin molded product of the present invention, in the process of molding a molded product having a hollow portion using a mold, it is possible to prevent defects such as contact between the parts that form the mold and the molded product falling when the mold is opened, and to reduce the risk of such defects occurring. [Brief explanation of the drawings]

[0011] [Figure 1] 1 is a perspective view schematically showing a resin molded product according to an embodiment of the present invention; [Figure 2] 2 is a side view of the resin molded product shown in FIG. 1 as viewed from the left and right sides. [Figure 3] FIG. 2 is an enlarged perspective view showing a main part of the resin molded product shown in FIG. 1. [Figure 4] 4 is a cross-sectional view schematically showing a cross section corresponding to line IV-IV in FIG. 2 in a mold for molding a resin molded product. [Figure 5] 3 is an enlarged cross-sectional view schematically showing a cross section corresponding to line VV in FIG. 2 in a mold for molding a resin molded product. [Figure 6] 1A and 1B are schematic diagrams illustrating the assembly of a resin molded product. [Figure 7] FIG. 10 is an enlarged perspective view showing a main part of a resin molded product according to a modified example. DETAILED DESCRIPTION OF THE INVENTION

[0012] Hereinafter, preferred embodiments of the present invention will be described with reference to the drawings. Fig. 1 is a perspective view schematically showing a resin molded product according to this embodiment, Fig. 2 is a side view of the resin molded product according to this embodiment as seen from the left and right sides, and Fig. 3 is an enlarged perspective view showing a main part of the resin molded product according to this embodiment.

[0013] The resin molded product 1 of this embodiment is, for example, one of the components used in automobiles. Note that, in the present invention, the use of the resin molded product 1 is not particularly limited. With regard to the resin molded product 1 of this embodiment, the front-rear direction is the direction along the length of the hollow portion 11 provided in the cylindrical resin molded product 1 (see FIG. 2). In particular, in this embodiment, of a pair of openings provided in the cylindrical resin molded product 1 and communicating with the hollow portion 11, the direction from the opening with the larger opening area to the opening with the smaller opening area is defined as the front, and the direction opposite thereto is defined as the rear.

[0014] The up-down direction is one of the directions perpendicular to the front-rear direction, and in the present embodiment, for example, is a direction perpendicular to the flat surfaces 12 and 13 described below that are provided on the resin molded product 1. The left-right direction is a direction perpendicular to the front-rear direction and the up-down direction, and in the present embodiment, for example, is a direction parallel to the flat surfaces 12 and 13 that are provided on the resin molded product 1.

[0015] The resin molded product 1 of this embodiment is formed by injection molding a synthetic resin using a mold 50 such as the one shown in Figures 4 and 5, and has an elongated shape extending in one direction (front-to-rear direction). The resin molded product 1 has a cylindrical component main body 10, four protrusions 20 protruding from the outer surface of the component main body 10, a front flange 31 provided at the front end of the component main body 10, and a rear flange 32 provided at the rear end of the component main body 10.

[0016] The component main body 10 has a cylindrical shape with a hollow portion (internal space) 11 provided inside. The front and rear ends of the component main body 10 are provided with a front opening and a rear opening that communicate with the hollow portion 11. The outer shape of a cross section of the component main body 10 perpendicular to the front-to-rear direction has a substantially oval or elliptical shape with the vertical dimension smaller than the horizontal dimension.

[0017] Within component body 10, hollow portion 11 extends straight in the front-to-rear direction from the front opening to the rear opening of component body 10 (i.e., across the entire front-to-rear direction of the component body). This component body 10 is formed so that the area of ​​a cross section of hollow portion 11 perpendicular to the front-to-rear direction gradually decreases toward the front.

[0018] In the present invention, the component main body 10 of the resin molded product 1 may be formed into a tubular shape other than a cylindrical shape, such as a rectangular tube. Furthermore, the hollow portion 11 of the component main body 10 may be provided only in a partial region in the front-to-rear direction of the component main body 10, rather than the entire front-to-rear direction of the component main body 10 as in this embodiment, and may be formed so as to open at either the front end or the rear end of the component main body 10.

[0019] The component main body 10 has an upper flat surface (upper surface) 12 and a lower flat surface (lower surface) 13 whose outer peripheral surfaces are formed as flat surfaces, and left and right side curved surface portions 14 whose outer peripheral surfaces are formed as convex curved surfaces. The upper flat surface portion 12 and the lower flat surface portion 13 of the component main body 10 are arranged parallel to the left and right direction. The lower flat surface portion 13 of the component main body 10 is arranged at an angle relative to the upper flat surface portion 12 in a side view of the resin molded product 1 (see FIG. 2 ) so that the height dimension (dimension in the vertical direction) of the hollow portion 11 gradually decreases toward the front opening.

[0020] The protrusions 20 include a first protrusion 20a and a second protrusion 20b provided on the upper surface (one surface) 12 of the component main body 10, and a third protrusion 20c and a fourth protrusion 20d provided on the lower surface (the other surface) 13 of the component main body 10. The protrusions 20 have substantially the same structure, although the overall size of the protrusions 20 and / or the size of each portion of the protrusions 20 differ from one another. Specifically, each protrusion 20 includes a rib portion 21 that is substantially U-shaped in a plan view or a bottom view of the resin molded product 1, and a guide portion 24 that extends forward from the front end of the rib portion 21.

[0021] For example, when the component body 10 is divided into a front half and a rear half based on the center in the front-to-rear direction, the first protrusion 20a is disposed on the upper surface of the rear half of the component body 10, and the second protrusion 20b is disposed on the upper surface of the front half of the component body 10. The third protrusion 20c is disposed on the lower surface of the rear half of the component body 10, and the fourth protrusion 20d is disposed on the lower surface of the front half of the component body 10.

[0022] The first protrusion 20a to the fourth protrusion 20d are each provided in a region including at least the upper flat surface portion 12 or the lower flat surface portion 13 of the component body 10. Specifically, the first protrusion 20a and the second protrusion 20b are arranged in series along the front-to-rear direction, for example, toward the right side of the component body 10 in a plan view of the component body 10. Furthermore, the first protrusion 20a and the second protrusion 20b are provided in the region of the upper flat surface portion 12 of the component body 10 in the left-right direction, or are provided in a region including the upper flat surface portion 12 of the component body 10 and the boundary between the upper flat surface portion 12 and the right-side curved surface portion 14 of the component body 10.

[0023] The third protrusion 20c and the fourth protrusion 20d are arranged in series along the front-to-rear direction at a position closer to the left side of the component main body 10, for example, when viewed from the bottom of the component main body 10. Furthermore, the third protrusion 20c and the fourth protrusion 20d are provided in the region of the lower flat surface 13 of the component main body 10 in the left-right direction, or are provided in a region spanning the lower flat surface 13 of the component main body 10 and the left-side curved surface 14 of the component main body 10 (in other words, a region including the lower flat surface 13, the boundary between the lower flat surface 13 and the left-side curved surface 14, and the left-side curved surface 14).

[0024] Furthermore, the first protrusion 20a and the second protrusion 20b on the upper surface side and the third protrusion 20c and the fourth protrusion 20d on the lower surface side are arranged in staggered positions so that, for example, when viewed from the side of the resin molded product 1 (Figure 2), their positions are shifted in the front-to-back direction and the upper surface side and the lower surface side are arranged alternately.

[0025] Each of the rib portions 21 of the first protruding portion 20a to the fourth protruding portion 20d has a linear vertical rib portion (first rib portion) 22 arranged along the front-rear direction or arranged substantially along the front-rear direction, and a plurality of horizontal rib portions (second rib portions) 23 protruding from the vertical rib portion 22 toward one side in the left-right direction. For example, in the first protruding portion 20a to the fourth protruding portion 20d of this embodiment, each of the rib portions 21 has one vertical rib portion 22 and two horizontal rib portions 23. Note that the direction substantially along the front-rear direction includes, for example, a direction inclined within ±10° with respect to the front-rear direction.

[0026] The vertical rib portion 22 of each protrusion 20 is formed with a constant height dimension (protrusion dimension). In this case, the height dimension of the vertical rib portion 22 is set to be the same as or approximately the same as the height dimension of an ejector pin 53 (described later) that is provided corresponding to the mold 50. Here, the corresponding ejector pin 53 refers to the ejector pin 53 that is provided so as to come into contact with the vertical rib portion 22 when the resin molded article 1 is extruded by the ejector pin 53 to release the resin molded article 1 from the mold 50.

[0027] Each vertical rib portion 22 has a flat upper or lower surface and flat left and right wall surfaces that are arranged parallel to each other. In this case, the upper or lower surface of the vertical rib portion 22 is arranged at a position spaced apart from the component body portion 10 in the vertical direction and is arranged parallel to the upper flat surface portion 12 or the lower flat surface portion 13 of the component body portion 10. The height dimension (protrusion dimension) of the vertical rib portion 22 refers to the dimension in the vertical direction from the position of the upper flat surface portion 12 or the lower flat surface portion 13 of the component body portion 10 to the upper or lower surface of the vertical rib portion 22.

[0028] In each vertical rib portion 22, either the left side wall surface or the right side wall surface of the vertical rib portion 22 is formed as a pressing surface that is contacted and pressed by the ejector pin 53 of the mold 50 when the resin molded article 1 is released from the mold 50. The pressing surface of the vertical rib portion 22 is set on the surface of the vertical rib portion 22 that faces the fixed mold 51 of the mold 50 when the resin molded article 1 is molded in the mold 50.

[0029] 4 and 5, when the resin molded article 1 of this embodiment is molded using the mold 50 shown in Fig. 4 and Fig. 5, the portion of the resin molded article 1 to the left of the vertical rib portion 22 of the protruding portion 20 is molded by the fixed mold 51 of the mold 50, as will be described later. Furthermore, when the resin molded article 1 is released from the mold, the ejector pin 53 of the mold 50 comes into contact with the vertical rib portion 22 of the resin molded article 1 from the left side of the resin molded article 1 and presses the vertical rib portion 22. Therefore, the left side wall surfaces (inner side wall surfaces) of the vertical rib portion 22 of the first protruding portion 20a and the second protruding portion 20b and the left side wall surfaces (outer side wall surfaces) of the vertical rib portion 22 of the third protruding portion 20c and the fourth protruding portion 20d become pressing surfaces pressed by the ejector pin 53.

[0030] In the resin molded product 1 of this embodiment, the hollow portion 11 provided in the component main body 10 and the pressing surfaces (left wall surfaces) of the vertical rib portions 22 provided on each of the first to fourth protruding portions 20a to 20d are arranged at positions spaced apart from each other at least in the vertical direction of the resin molded product 1. In this case, the vertical direction of the resin molded product 1 is a direction that intersects with the pressing direction in which the ejector pin 53 presses the vertical rib portions 22 (the moving direction of the ejector pin 53).

[0031] In this way, the hollow portion 11 provided within the component main body 10 and the pressing surfaces provided on the first protrusion 20a to fourth protrusion 20d are arranged at a distance in the vertical direction. Therefore, when molding the resin molded product 1 using the mold 50, even if the slide top 54 installed in the mold 50 to form the vertical hollow portion 11 and the ejector pin 53 installed in the mold 50 to hold and extrude the resin molded product 1 move due to a malfunction or the like, it is possible to reliably avoid the problem of the slide top 54 and the ejector pin 53 coming into contact with each other.

[0032] The two horizontal rib portions 23 provided on each protrusion 20 each have a flat upper or lower surface, flat front and rear wall surfaces arranged parallel to each other, and a tip surface that extends in a curved manner from the upper or lower surface and continues to the upper flat surface portion 12 or the left side curved surface portion 14 of the component body 10. The upper or lower surface of each horizontal rib portion 23 is arranged at a position spaced apart from the component body 10 in the vertical direction, and is arranged parallel to the upper flat surface portion 12 or the lower flat surface portion 13 of the component body 10.

[0033] The two horizontal rib portions 23 provided on each protrusion 20 are formed so that the maximum height of each horizontal rib portion 23 is the same as the height of the vertical rib portion 22. Here, the height of the horizontal rib portion 23 refers to the dimension in the vertical direction from the position of the upper flat surface 12 or the lower flat surface 13 of the component main body 10 to the upper surface or lower surface of the horizontal rib portion 23. Furthermore, the upper surface of the horizontal rib portion 23 continues from the upper surface of the vertical rib portion 22, forming a single plane with the upper surface of the vertical rib portion 22, and has a portion that is arranged parallel to the upper surface of the vertical rib portion 22.

[0034] The two horizontal rib portions 23 provided on each protrusion 20 are arranged parallel to and spaced apart from each other in the front-to-rear direction. The two horizontal rib portions 23 on each protrusion 20 extend from the left wall surface (pressing surface) of the vertical rib portion 22 along a direction that intersects with the direction perpendicular to the installation direction (front-to-rear direction) of the vertical rib portion 22 (or the opening / closing direction of the mold 50).

[0035] 5, the two horizontal rib portions 23 extend in the direction in which the ejector pin 53 of the mold 50 moves relative to the protrusion 20. Specifically, the two horizontal rib portions 23 in this embodiment extend straight from the left wall surface of the vertical rib portion 22 diagonally rearward to the left, so as to be inclined with respect to the left-right direction.

[0036] In this case, all of the horizontal ribs 23 provided on the first to fourth protrusions 20a to 20d are arranged parallel to one another. The horizontal ribs 23 are also arranged so that the angle between the vertical rib 22 and the horizontal rib 23 is greater than 0° and less than 90°, preferably between 45° and 80°.

[0037] The two horizontal rib portions 23 provided on each protrusion 20 engage with the ejector pins 53 during the molding process of the resin molded article 1, thereby serving as holding portions that hold the resin molded article 1 on the ejector pins 53. The horizontal rib portions 23 functioning as holding portions are provided at an angle with respect to the left-right direction of the resin molded article 1, so that in the molding process described below, when the fixed mold (cavity) 51 and the movable mold (core) 52 of the mold 50 are opened after the resin molded article 1 has cooled, the ejector pins 53 inserted between the two horizontal rib portions 23 of each protrusion 20 can hold the resin molded article 1 (particularly the protrusion 20 of the resin molded article 1). This prevents problems such as the resin molded article 1 coming off the fixed mold 51 and sticking to the movable mold 52 when the mold 50 is opened, making it difficult to remove the resin molded article 1 from the movable mold 52, and the resin molded article 1 coming off the fixed mold 51 and falling, resulting in molding defects.

[0038] The protruding length of the horizontal rib portion 23 from the vertical rib portion 22 is set to be greater than the thickness dimension between the left wall surface and the right wall surface of the vertical rib portion 22, and smaller than half the length dimension in the front-to-rear direction of the vertical rib portion 22. Here, the protruding length of the horizontal rib portion 23 from the vertical rib portion 22 means the length from the position where the horizontal rib portion 23 connects to the vertical rib portion 22 to the tip surface of the horizontal rib portion 23, at the center position between the front wall surface and the rear wall surface of the horizontal rib portion 23, and at the center position of the horizontal rib portion 23 in the up-down direction.

[0039] As described above, the protruding length of the horizontal rib portions 23 is set to be greater than the thickness dimension of the vertical rib portions 22, which makes it easier for the ejector pin 53 inserted between the two horizontal rib portions 23 of one protruding portion 20 to stably hold the resin molded article 1. Furthermore, the protruding length of the horizontal rib portions 23 is set to be less than half the length dimension of the vertical rib portions 22, which makes it easier to remove the resin molded article 1 from the ejector pin 53 after the ejector pin 53 pushes the resin molded article 1 out of the fixed mold 51. Furthermore, in this embodiment, the first to fourth protrusions 20a to 20d are each provided at a position where the right wall surface of the vertical rib portion 22 coincides with the parting line PL of the mold 50 (see FIGS. 4 and 5).

[0040] The guide portion 24 of each protrusion 20 is provided continuously so as to extend straight forward from the front end of the vertical rib portion 22 of that protrusion 20, and is arranged parallel to the vertical rib portion 22. Each guide portion 24 has a guide shape in which the upper surface of the guide portion 24 slopes downward toward the front so that the height dimension (protrusion dimension) of the guide portion 24 from the component main body 10 gradually decreases toward the front. The thickness dimension between the left side wall surface and the right side wall surface of each guide portion 24 is the same as the thickness dimension of the vertical rib portion 22 of that protrusion 20 (the thickness dimension between the left side wall surface and the right side wall surface).

[0041] The front flange portion 31 of the resin molded product 1 is provided integrally with the component main body 10 at the front end portion thereof. The front flange portion 31 is formed to protrude outward from the entire outer peripheral surface of the component main body 10. The front flange portion 31 is provided at an angle relative to the vertical direction so that the upper end portion is located further forward than the lower end portion in a side view of the resin molded product 1.

[0042] The rear flange portion 32 of the resin molded article 1 is provided integrally with the component main body 10 at the rear end thereof. The rear flange portion 32 is formed to protrude outward from the entire outer peripheral surface of the component main body 10. The rear flange portion 32 is provided at an incline in the vertical direction so that the upper end is located rearward of the lower end in a side view of the resin molded article 1.

[0043] The front flange portion 31 and the rear flange portion 32 of the resin molded product 1 are used when attaching the resin molded product 1 to another component, thereby stabilizing the attachment position and attachment orientation of the resin molded product 1. Note that in the present invention, the shapes, sizes, installation positions, etc. of the front flange portion 31 and the rear flange portion 32 of the resin molded product 1 are not particularly limited. Also, in the present invention, the resin molded product 1 may be formed without the front flange portion 31 and the rear flange portion 32.

[0044] Next, a method for molding the resin molded product 1 of the present embodiment described above using the mold 50 will be described. First, a preparation step is performed to prepare a mold 50 as shown in Figures 4 and 5. In Figure 4, hatching showing a cross section of the mold is omitted to make the mold structure easier to understand. This mold 50 has a fixed mold (cavity) 51, a movable mold (core) 52 arranged to be movable relative to the fixed mold 51 so as to open and close the mold 50, four ejector pins 53 arranged in insertion holes 51a formed in the fixed mold 51, and a slide piece 54 installed to form a hollow portion 11 in the resin molded product 1.

[0045] The mold 50 is closed by holding the mating surfaces of the fixed mold 51 and the movable mold 52 in contact with each other, thereby causing the fixed mold 51 and the movable mold 52 to come into close contact with each other. When the mold 50 is closed, a space (cavity) having a shape corresponding to the resin molded article 1 is provided between the fixed mold 51 and the movable mold 52. The part where the fixed mold 51 and the movable mold 52 are butted together forms a parting line PL. In this embodiment, the parting line PL of the mold 50 is set along the position of the left wall surface of the vertical rib portion 22 with respect to the resin molded article 1 to be molded.

[0046] Each ejector pin 53 of the mold 50 is provided in an insertion hole 51a of the fixed mold 51 so as to be able to move linearly back and forth relative to the fixed mold 51. In this case, the movement direction of the ejector pin 53 is set so as to be parallel to the extension direction of the horizontal rib portion 23 of the resin molded article 1 when, for example, the mold 50 is viewed in a cross section perpendicular to the up-down direction of the resin molded article 1.

[0047] Each ejector pin 53 provided in the mold 50 has a tip surface 53a that comes into contact with the protrusion 20 of the resin molded product 1. The tip surface 53a of the ejector pin 53 is formed into a flat surface so that it can form the left wall surface (pressing surface) of the vertical rib portion 22 of the resin molded product 1, and is disposed at an angle with respect to the movement direction of the ejector pin 53, as shown in Fig. 5. In this case, the inclination angle of the tip surface 53a with respect to the movement direction of the ejector pin 53 is set corresponding to the inclination angle of the horizontal rib portion 23 provided on the resin molded product 1 with respect to the vertical rib portion 22.

[0048] The slide piece 54 of the mold 50 has a portion corresponding to the shape of the hollow portion 11 of the resin molded product 1. The slide piece 54 is provided so as to be reciprocable in the front-to-rear direction relative to the fixed mold 51 so as to be inserted into and extracted from the space between the fixed mold 51 and the movable mold 52.

[0049] Next, a molding process is performed to mold the resin molded product 1 using the prepared mold 50. In this molding process, first, the fixed mold 51 and the movable mold 52 of the prepared mold 50 are butted together and the mold 50 is closed. As a result, a space having a predetermined shape is formed between the fixed mold 51 and the movable mold 52. In addition, the slide top 54 of the mold 50 is moved and held at a position where a part of the slide top 54 passes through the space between the fixed mold 51 and the movable mold 52. The ejector pin 53 is held so that the tip surface 53a of the ejector pin 53 is aligned with the position of the left wall surface of the vertical rib portion 22 of the resin molded product 1 to be molded.

[0050] With the mold 50 closed as described above, synthetic resin is supplied from a gate (not shown) provided in the mold 50 into the space inside the mold 50, filling the space with the synthetic resin. The synthetic resin is then cooled and solidified, and the resin molded product 1 is formed inside the mold 50.

[0051] After the resin molded article 1 is molded in the mold 50, an ejection step is performed to eject the resin molded article 1 from the mold 50. In this ejection step, first, the movable die 52 of the mold 50 is moved in a direction away from the fixed die 51. Also, the slide piece 54 of the mold 50 is moved so as to be pulled out from the resin molded article 1. At this time, the hollow portion 11 of the resin molded product 1 and the left wall surface (pressing surface) of each of the four protrusions 20 are positioned so as to be spaced apart from each other in the vertical direction, so that even if the slide top 54 is moved, the slide top 54 will not come into contact with the ejector pin 53.

[0052] 5, for example, with respect to the resin molded article 1 molded within the mold 50, each ejector pin 53 is in contact with the left side surface of the vertical rib portion 22 of each protrusion 20 of the resin molded article 1, and the tip portion of the ejector pin 53 is inserted between the two horizontal rib portions 23 of each protrusion 20. In addition, the ejector pin 53 and the two horizontal rib portions 23 of each protrusion 20 of the resin molded article 1 are arranged in a direction inclined with respect to the opening and closing direction of the mold 50.

[0053] As a result, when the movable die 52 of the mold 50 is separated from the fixed die 51 and the mold 50 is opened, each of the four ejector pins 53 is engaged with the corresponding protrusion 20 of the resin molded article 1, and the resin molded article 1 can be stably held and secured on the fixed die 51 side by the four ejector pins 53. This prevents the resin molded article 1 from coming off the fixed die 51 of the mold 50 and being fixed to the movable die 52, and from coming off the fixed die 51 of the mold 50 and falling.

[0054] After moving the movable die 52 and the slide piece 54 of the mold 50 as described above, the four ejector pins 53 held in the insertion holes 51a of the fixed die 51 are advanced toward the protrusions 20 of the resin molded article 1. As a result, the four ejector pins 53 press against the four protrusions 20 of the resin molded article 1 held in the fixed die 51, respectively, and the resin molded article 1 can be released from the fixed die 51.

[0055] In particular, in this embodiment, the first protrusion 20a and the second protrusion 20b provided on the upper surface of the component body 10 and the third protrusion 20c and the fourth protrusion 20d provided on the lower surface are arranged in a staggered positional relationship as described above. Therefore, the resin molded product 1 can be pressed in a balanced manner by the four ejector pins 53, and can be smoothly removed from the fixed mold 51 and collected.

[0056] By carrying out the above-described preparation step, molding step, and removal step, the resin molded product 1 of this embodiment shown in FIGS. 1 to 3 can be stably manufactured. The resin molded article 1 of this embodiment to be manufactured is provided with the four protrusions 20 each having the vertical rib portion 22 and two horizontal rib portions 23 described above, and therefore when the mold 50 is opened after molding of the resin molded article 1, the resin molded article 1 can be stably held in the fixed mold 51 of the mold 50. This prevents the resin molded article 1 from being fixed to the movable mold 52 side, and also prevents molding defects from occurring in the resin molded article 1 due to, for example, the resin molded article 1 being dropped (in other words, the risk of such molding defects occurring in the resin molded article 1 can be reduced).

[0057] Furthermore, in the resin molded product 1 of this embodiment, the hollow portion 11 and the left wall surfaces (pressing surfaces) of the four protrusions 20 are arranged at positions spaced apart from each other in the vertical direction. Therefore, as described above, when the slide top 54 and / or the ejector pin 53 are moved, the slide top 54 and the ejector pin 53 can be reliably prevented from contacting each other, thereby preventing problems such as damage to the mold 50 caused by the contact between them.

[0058] Thereafter, the manufactured resin molded product 1 of this embodiment is inserted into a panel member 60 provided with an insertion opening 61, as shown in Figure 6, and the rear flange portion 32 of the resin molded product 1 is fixed to the panel member 60 using a fastening member such as a screw (not shown), thereby attaching it to a predetermined position.

[0059] In this case, the resin molded product 1 of this embodiment is provided with a guide portion 24 having a guide shape on each of the four protrusions 20. As a result, when the resin molded product 1 is inserted into the insertion opening 61 of the panel member 60, the guide portion 24 of each protrusion 20 can guide the resin molded product 1 to an appropriate position with respect to the insertion opening 61 of the panel member 60, making it less likely that the resin molded product 1 will get caught on the panel member 60, and allowing the resin molded product 1 to be smoothly assembled to the panel member 60. Therefore, the ease of assembly of the resin molded product 1 can be improved.

[0060] The present invention is not limited to the above-described embodiments, and various modifications are possible as long as they have substantially the same configuration as that described in the claims of the present invention and provide similar effects.

[0061] For example, the resin molded product 1 of the above-described embodiment has four protrusions 20 protruding from the component main body 10, and each protrusion 20 is formed by one vertical rib portion 22, two horizontal rib portions 23, and one guide portion 24. However, in the present invention, the number and positions of the protrusions 20 provided on the resin molded product 1 are not particularly limited and can be changed as desired. Note that, in order to stably press the resin molded product 1 with the ejector pins 53 of the mold 50, it is preferable that at least two protrusions 20 be provided for one resin molded product 1. Furthermore, the size of each protrusion 20 can be changed as desired depending on the application of the resin molded product 1, the size and shape of the mold 50 used to mold the resin molded product 1, the size of the ejector pins 53 provided on the mold 50, etc.

[0062] Furthermore, in the present invention, the number of horizontal ribs provided on one protrusion is not particularly limited as long as at least two horizontal ribs are provided on one protrusion. For example, as shown in Fig. 7, which is an enlarged view of a protrusion 40 of a resin molded product 1a according to a modified example, one protrusion 40 may be provided with one vertical rib 42, three or more horizontal ribs 43, and a guide portion 44 as the rib portion 41. In this case, the number of ejector pins installed on the mold corresponding to one protrusion 40 and / or the shape of the tip of the ejector pin are changed corresponding to the number of horizontal rib portions 43 provided on the protrusion 40.

[0063] Even if the number of horizontal rib portions 23 provided on one protrusion 40 is three or more, the resin molded article 1a can be more stably held on the fixed mold side by the ejector pin of the mold when the mold is opened. Therefore, the resin molded article 1a according to the modified example can more effectively prevent the resin molded article 1a from being fixed to the movable mold and from causing molding defects due to the resin molded article 1 dropping.

[0064] In the above-described embodiment, the left wall surface of the vertical rib portion 22 of the protruding portion 20 of the resin molded product 1 is formed as a pressing surface that is pressed by the ejector pin 53. However, in the present invention, when the mold is opened after molding the resin molded product, for example, in a case where the resin molded product is held on the movable mold side of the mold, the pressing surface of the resin molded product and at least two horizontal ribs may be provided on the surface of the vertical rib portion facing the movable mold. In this case, it is preferable that the ejector pin of the mold be provided on the movable mold. Furthermore, in the present invention, the shape and size of the resin molded product are not particularly limited as long as the resin molded product has at least a hollow portion and a pressing surface that is pressed by an ejector pin of a mold. [Explanation of symbols]

[0065] 1,1a Resin molded products 10 Component body 11 Hollow part (inner space part) 12 Upper plane part (top surface) 13 Lower plane part (lower surface) 14 Side curved part 20 Protrusion 20a 1st protrusion 20b Second protrusion 20c 3rd protrusion 20d 4th protrusion 21 Rib section 22 Vertical rib section (first rib section) 23 Horizontal rib section (second rib section) 24 Guidance part 31 Front flange 32 Rear flange 40 Protrusion 41 Rib section 42 Vertical rib section 43 Horizontal rib section 44 Guidance part 50 molds 51 Fixed type (cavity) 51a Insertion hole 52 Movable type (core) 53 Ejector pin 53a Tip surface 54 Slide piece 60 Panel members 61 Insertion opening PL parting line

Claims

1. A resin molded product obtained by molding a synthetic resin using a mold, the resin molded product has a hollow portion formed inside the resin molded product and at least one pressing surface that is pressed when the resin molded product is released from the mold, The hollow portion and the pressing surface are positioned to be spaced apart from each other in a direction intersecting with the pressing direction of the pressing surface. A resin molded product characterized by:

2. the resin molded product has a main body portion having the hollow portion and at least one protrusion portion protruding from the main body portion, The protrusion has the pressing surface and a holding portion extending from the pressing surface in a direction intersecting the opening and closing direction of the mold. The resin molded product according to claim 1.

3. The protrusion has a guide shape that gradually reduces the protruding dimension from the main body in one direction. The resin molded product according to claim 2.

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