JP2011177935A - Core-back type foamed resin molding mold, core-back type foamed resin molding method, and container-like foamed molding - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a core-back type foamed resin molding mold which allows a bead to be provided on the distal end face of a side wall of a container-like foamed molding while suppressing the manufacturing cost of the mold, a core-back type foamed resin molding method, and the container-like foamed molding. <P>SOLUTION: The core-back type foamed resin molding mold 21 includes a thickening molding part 24B molding a distal end edge (distal end thick part 53) of a side wall 52, and a side wall body molding part 24A molding a part (side wall body part 54) other than the distal end edge of the side wall 52, in a cavity 24. When core-backing the molding mold 21 by filling molten resin in the cavity 24, the end face of the distal end thick part 53 molded at the thickening molding part 24B is raised to form the bead 55. That is, the bead 55 can be formed even without forming the groove for the bead in the molding mold 21, thus suppressing the manufacturing cost of the molding mold 21. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to a core-back type foamed resin mold, a core-back type foamed resin molding method, and a container-shaped foam-molded article that are molded by foaming a molten resin with a core back of a mold.

  For example, an engine cover (see Patent Document 1) that is an injection-molded product, a container-shaped resin molded product such as a resin tray or a resin cap, generally prevents a sharp edge from being formed at the leading edge of the side wall. Therefore, a bead that is a rounded protrusion is formed on the front end surface of the side wall.

JP 2007-114617 A (paragraphs [0024], [0025], FIG. 1)

  However, when the ball edge is formed by conventional injection molding, as shown in FIG. 12, a groove 2 for the ball edge having an arc surface in the portion of the mold 1 where the front end surface of the side wall is formed is processed. There is a problem that the mold manufacturing cost becomes expensive.

  The present invention has been made in view of the above circumstances, and a core back type foamed resin mold and a core back type mold capable of providing a bead on the front end surface of a side wall of a container-like foam molded product while suppressing mold production costs. An object is to provide a foamed resin molding method and a container-like foam molded product.

  A container-like foam molded article (50) according to the invention of claim 1 made to achieve the above object is a container-like foam molded article (50) molded by a core back type foam molding method, and has a side wall. The entire tip edge in (52) is provided with a tip thick part (53) that is thicker than the part other than the tip edge, and the tip face of the side wall (52) that is also the end face of the tip thick part (53) is rounded. It is characterized by the formation of a bead (55) which is a protruding ridge.

  The invention of claim 2 is characterized in that, in the container-like foam molded article (50) of claim 1, the tip edge of the side wall (52) is increased inwardly to form the tip thick part (53). Have

  According to a third aspect of the present invention, in the container-like foamed molded product (50) according to the first or second aspect, the thickness is increased so that the thickness gradually increases from the position closer to the tip of the side wall (52) toward the tip. It is characterized in that the tip thick part (53) is formed.

  According to a fourth aspect of the present invention, in the container-like foamed molded article (50) according to any one of the first to third aspects, the wall thickness (t2) of the portion other than the tip edge of the side wall (52) is 1.5 to 3.0 [mm], and the thickness (t3) of the tip thick portion (53) is 2.2 to 3.0 [mm].

  A core back type foamed resin mold (21) according to the invention of claim 5 made to achieve the above object is a core back type foamed resin mold for foam molding of a container-like foam molded product (50). 21), a thick molded portion (53) for forming a thick tip portion (53) thicker than a portion other than the tip edge on the entire tip edge of the side wall (52) of the container-like foam molded product (50). 24B) and a ball back (55), which is a rounded protrusion, can be formed on the front end surface of the side wall (52) which is also the end surface of the thick end portion (53) by the core back. Have

  According to a sixth aspect of the present invention, in the core back type foamed resin mold (21) of the fifth aspect, the outer molding surface (23S) for molding the outer surface of the side wall (52) in the thick molded portion (24B). ) Is inclined with respect to the opening / closing direction of the core back type foamed resin molding die (21), while the inner molding surface (22S) for molding the inner surface of the side wall (52) of the thick molding portion (24B) is The core back type foamed resin mold (21) is characterized by being parallel to the opening and closing direction.

  The invention according to claim 7 is the core back type foamed resin mold (21) according to claim 5 or 6, wherein the side wall main molding part (24A) for molding a part other than the tip edge of the side wall (52). The width (c2) of the cavity (24) is less than 2.0 [mm] before the core back, and the width (c3) of the cavity (24) at the end face of the thick molded part (24B) is the same as that before the core back. It is characterized by being configured to be 2.2 [mm] or more in the state.

  In order to achieve the above object, the core back type foamed resin molding method according to the invention of claim 8 is the core back type foamed resin molding die (21) filled with the molten resin after filling the cavity (24). In the core back type foamed resin molding method in which the container-like foamed molded product (50) is foam-molded, the entire tip edge of the side wall (52) of the container-shaped foamed molded product (50) is thicker than the portion other than the tip edge. A thick-walled molded part (24B) for molding the thick-walled tip thick part (53) is provided in the cavity (24), and the side wall (52 which is also the end face of the thick-walled part (53) is provided by the core back. ) Has a feature in that a ball edge (55), which is a rounded protrusion, is formed on the front end surface of ().

  According to a ninth aspect of the present invention, in the core back type foamed resin molding method according to the eighth aspect, the cavity (24) in the side wall main molding portion (24A) for molding a portion other than the tip edge of the side wall (52). The width (c2) is set to less than 2.0 [mm], and the width (c3) of the cavity (24) at the end face of the thick molded portion (24B) is set to 2.2 [mm] or more, and the cavity (24) It is characterized in that it is filled with molten resin.

[Inventions of Claims 1, 2, 3 and 4]
According to the structure of this invention, the part which shape | molds the front end surface of the side wall (52) of a container-like foaming molded product (50) among the foaming molds for shape | molding a container-like foaming molded product (50) is made flat. However, when the foaming mold is core-backed, the end face of the thick end portion (53) is raised to form the bead (55). That is, the ball edge (55) can be formed without forming the groove for the bead on the foaming mold, and the mold production cost of the foam mold can be suppressed. Further, by making the portion other than the front end edge of the side wall (52) thinner than the front end edge, it is possible to reduce the weight of the container-like foamed molded product (50) and reduce the resin as the raw material. Specifically, as in the invention of claim 4, the thickness (t2) of the side wall (52) other than the tip edge is 1.5 to 3.0 [mm] (preferably 2.0 [ mm]), and the thickness (t3) of the tip thick part (53) is 2.2 to 3.0 [mm] (preferably 2.4 [mm]), thereby maintaining a predetermined strength. However, a good bead can be formed.

  Here, the distal end thick portion (53) may be formed by increasing the distal end edge of the side wall (52) outward, or the distal end edge of the side wall (52) may be formed as in the invention of claim 2. You may increase the thickness on the inner side. According to invention of Claim 2, a front-end | tip thick part (53) can be made not conspicuous.

  Further, the tip thick part (53) may be formed by increasing the thickness so that the thickness increases in a stepped manner near the tip of the side wall (52), or the side wall as in the invention of claim 3. It may be formed by increasing the thickness so that the thickness gradually increases from the position closer to the tip of (52) toward the tip. According to the third aspect of the present invention, it is possible to avoid the formation of a step due to the increase in thickness, and it is possible to prevent the tip thick portion (53) from being caught.

[Inventions of Claims 5 and 8]
According to invention of Claim 5 and 8, the part which shape | molds the front end surface of the side wall (52) of a container-like foaming molding product (50) among the core back type foaming resin molding dies (21) is made flat. In addition, when the core-back type foamed resin mold (21) is core-backed, the end surface of the thick-walled portion (53) is raised to form the bead (55). That is, the ball edge (55) can be formed without forming the groove for the ball edge in the core-back type foamed resin mold (21), and the mold manufacturing cost can be suppressed. Further, in the container-like foamed molded article (50) molded by the core back type foamed resin mold (21) of the present invention, only the leading edge of the side wall (52) is thick, and the leading edge of the side wall (52). Since the other portions are thinner than the leading edge, it is possible to reduce the weight of the container-like foamed molded product (50) and to reduce the resin as the raw material.

[Invention of claim 6]
The container-like foamed molded product (50) molded by the core-back type foamed resin mold (21) according to claim 6 has an increased thickness on the leading edge of the side wall (52) so that the thickened tip (53) Since it is formed, the tip thick part (53) can be made inconspicuous. Further, the thick-walled portion (53) is formed by increasing the thickness so that the thickness gradually increases from the position closer to the tip of the side wall (52) toward the tip, so that the formation of a step due to the increased thickness is avoided. It is possible to prevent the tip thick portion (53) from being caught.

[Inventions of Claims 7 and 9]
The inventor does not form a bead (55) when the front end surface of the side wall (52) (the end surface of the front end thick portion (53)) is less than 2.0 [mm] in the state before the core back. , 2.2 [mm] or more, it was confirmed by experiments that a bead (55) was formed. According to the inventions of claims 7 and 9, the width (c2) of the cavity (24) in the side wall main molding part (24A) for molding a part other than the tip edge of the side wall (52) is set to the value before the core back. The width (c3) of the cavity (24) on the end face (tip face of the side wall (52)) of the thick molded part (24B) is set to less than 2.0 [mm] in the state and 2.2 in the state before the core back. [Mm] or more, so that the portion other than the tip edge of the side wall (52) is thinned to reduce the weight of the container-like foamed molded product (50) and reduce the resin as a raw material, 55) can be formed.

(A) The cross-sectional perspective view of the engine cover which concerns on one Embodiment of this invention, (B) The cross-sectional perspective view which expanded the front-end | tip part of the side wall. Front view of engine cover (A) Side cross-sectional view of mold before core back operation, (B) Side cross-sectional view of mold after core back operation (A) Enlarged side sectional view of the mold before the core back operation, (B) Enlarged side sectional view of the mold at the time of resin filling, (C) Enlarged side sectional view of the mold after the core back operation Enlarged side sectional view of the mold before core back operation (A) Enlarged side sectional view of the mold during resin filling, (B) Enlarged side sectional view of the mold after the core back operation Cross-sectional photo of the edge of the side wall of the engine cover Cross-sectional photo of the edge of the side wall of the engine cover Cross-sectional photo of the edge of the side wall of the engine cover Conceptual drawing of the cross section for contrasting the leading edge of the side wall Side cross-sectional view of the mold and the tip thick part after the core back operation Side view of a conventional mold

  Hereinafter, an embodiment of a container-like foamed molded article, a core back type foamed resin mold, and a core back type foamed resin molding method according to the present invention will be described with reference to FIGS. FIG. 1A shows an engine cover 50 for an automobile as an example of a “container-like foamed product” according to the present invention. The engine cover 50 has a flat container shape having a main plate wall 51 facing an engine (not shown) from above and a side wall 52 hanging downward from the outer edge of the main plate wall 51, and the side wall 52 is separated from the main plate wall 51. It is inclined so as to expand (toward the tip).

  A tip edge of the side wall 52 from the tip to the position near the tip is a thick tip portion 53 that is thicker than a portion of the side wall 52 other than the tip edge (hereinafter referred to as “side wall main portion 54”). Specifically, the side wall main portion 54 has a substantially constant thickness from the main plate wall 51 to the boundary portion between the front end thick portion 53 and the front end thick portion 53 gradually increases as it moves away from the side wall main portion 54. The thickness is increased to increase the thickness. More specifically, as shown in FIG. 1B, the distal end thick portion 53 is formed by increasing the distal end edge of the side wall 52 inward. A bevel 55 is provided on the front end surface of the side wall 52, which is also the end surface of the front end thick portion 53, which is a rounded and continuous ridge over the entire side wall 52. By providing this bead 55, the edge of the leading edge of the side wall 52 is eliminated, and for example, the angular feel when the hand is put on the leading edge of the side wall 52 when the engine cover 50 is attached or detached can be eliminated or alleviated. .

  Here, the dimensions of each part of the finished engine cover 50 are, for example, as follows. That is, the thickness of the main plate wall 51 (see “t1” in FIG. 2) is 2.7 [mm], and the thickness of the side wall main portion 54 (see “t2” in FIG. 2) is 2.0 [mm]. And the thickness (see “t3” in FIG. 2) at the end face of the tip thick portion 53 is 2.4 [mm]. Further, the amount of protrusion of the ball edge 55 (see “t4” in FIG. 2) is, for example, 1.0 [mm].

  A foam sound absorbing member having a sponge structure (not shown) is fixed to the surface of the engine cover 50 facing the engine so as to cover the main plate wall 51.

  This completes the description of the structure of the engine cover 50 of the present embodiment. Next, a method for manufacturing the engine cover 50 will be described. 3A shows a core back type foamed resin molding die 21 (hereinafter referred to as “molding die 21”) provided in the core back type foamed resin molding machine 20 for molding the engine cover 50. FIG. . The mold 21 includes, for example, a fixed mold 22 and a movable mold 23 that can be opened in the horizontal direction. The movable mold 23 is provided with a main recess 23A having an opening having the same shape as the planar shape of the engine cover 50, and the fixed mold 22 is provided with a main projection 22A that can be fitted into the main recess 23A. ing. The main protrusion 22A is inserted into the main recess 23A, and the fixed mold 22 and the movable mold 23 are closed. With the mold closed, the back and inner surfaces of the main recess 23A and the tip of the main protrusion 22A are closed. A cavity 24 for forming the engine cover 50 is formed between the surface and the outer surface.

  More specifically, the main plate wall 51 of the engine cover 50 is formed between the opposed surfaces 22T and 23T facing each other in the opening / closing direction (horizontal direction) of the fixed die 22 and the movable die 23, and the inner side surface 23S of the main recess 23A. And the side wall 52 of the engine cover 50 is formed between the outer surface 22S of the main projection 22A. The fixed mold 22 is formed with a liner 25 communicating with a cylinder (not shown) of the core back type foamed resin molding machine 20, and the melted resin composition is filled into the cavity 24 from the liner 25. .

  Here, the portion of the cavity 24 where the side wall 52 is formed is composed of a side wall main body forming portion 24A for forming the side wall main body portion 54 and a thick wall forming portion 24B for forming the distal end thick portion 53. ing. While the cavity width in the side wall main molded part 24A is substantially constant, the cavity width in the thick wall molded part 24B becomes wider as the distance from the side wall main molded part 24A increases.

  Specifically, as shown in FIG. 5, the inner surface 23S of the main recess 23A for molding the outer surface of the side wall 52 opens and closes the mold 21 so as to expand from the inner surface of the main recess 23A toward the opening end. Inclined with respect to direction. On the other hand, the outer side surface 22S of the main projection 22A that molds the inner side surface of the side wall 52 is parallel to the inner side surface 23S of the main recess 23A at a portion corresponding to the side wall main molding portion 24A, and the thick molding portion 24B. Is parallel to the opening / closing direction of the mold 21 (ie, horizontal).

  Now, when the mold 21 is in the mold closed state, as shown in FIG. 3A, the movable mold 23 comes into contact with a predetermined portion of the fixed mold 22 and is positioned at the fully closed position. As shown in FIG. 3B, the movable mold 23 can be held at the core back position where the movable mold 23 is moved backward from the fixed mold 22 by a predetermined amount b1 from the fully closed position. Due to the core back operation in which the movable mold 23 moves from the fully closed position to the core back position, the width of each part of the cavity 24 increases.

  The width of each part of the cavity 24 before the core back operation (see FIG. 3A) is as follows. That is, the width between the opposed surfaces 22T and 23T of the fixed mold 22 and the movable mold 23, which are the portions of the cavity 24 where the main plate wall 51 is molded, is 1.5 [mm] (see “c1” in FIG. 5). Thus, the width of the side wall main molded portion 24A is 1.5 [mm] (see “c2” in FIG. 5). Further, as described above, the thickness of the thick molded portion 24B becomes wider as the distance from the side wall main molded portion 24A increases, and the width of the end surface of the thick molded portion 24B (the front end surface of the side wall 52) is 2.4. [Mm] (see “c3” in FIG. 5). In the core back operation, the movable mold 23 moves backward to the side away from the fixed mold 22 by, for example, 1.2 [mm] (see “b1” in FIG. 3B), and the cavity after the core back operation is performed. The width of each part 24 is the thickness of the finished product of the engine cover 50 described above.

  The resin composition to be charged into the core back type foamed resin molding machine 20 includes a base resin as a main component of the engine cover 50 and a chemical foaming agent and other additives in a predetermined ratio. For example, the resin composition obtained by melting and kneading the above-mentioned materials is formed into pellets in advance, and the pellets are put into a cylinder (not shown) of the core back type foamed resin molding machine 20.

  Next, in a state where the movable mold 23 is disposed at the fully closed position (see FIGS. 3A, 4A, and 5), the resin composition in a molten state is filled into the cavity 24 from the liner 25 (FIG. 4). (See (B) and FIG. 6 (A)). Then, the molten resin composition is filled in the cavity 24. When the resin composition has spread over the entire cavity 24, as shown in FIGS. 4B and 6A, only the surface portion of the resin composition is solidified and the inside is in a molten state. The movable mold 23 is moved from the fully closed position to the core back position (see FIGS. 3B, 4C, and 6B). Thereby, the clearance gap of the above-mentioned cavity 24 is expanded, and the resin composition in a molten state foams. As a result, as shown in FIGS. 4 (C) and 6 (B), the engine cover 50 has an internal foam structure in which the vicinity of the surface is constituted by the non-foamed resin layer 50A and the inside is constituted by the foamed resin layer 50B. Become.

  Here, at the stage where the movable mold 23 is in the fully closed position and the resin composition is filled into the cavity 24, the front end surface of the side wall 52 (the end surface of the front end thick portion 53) is the main protrusion 22 A of the fixed mold 22. Is formed into a flat surface by a step surface 22D formed on the outer surface (see FIG. 6A). However, when the movable mold 23 is core-backed and the stepped surface 22D of the fixed mold 22 is retracted by a predetermined amount b1 from the position before the core-back operation, the front end surface of the side wall 52 that was a flat surface is caused by foaming of the resin composition. Is raised to form a rounded bead 55.

  When the entire resin in the cavity 24 is solidified, the movable mold 23 is separated from the fixed mold 22 and the engine cover 50 is taken out from the mold 21. Thereafter, the engine cover 50 is inserted into a mold (not shown) to form a sound absorbing foam member having a sponge structure (not shown), and all manufacturing steps of the engine cover 50 are completed.

  Thus, according to this embodiment, the part (step surface 22D) which shape | molds the front end surface of the side wall 52 of the engine cover 50 among the shaping | molding die 21 for shape | molding the engine cover 50 as a container-like foaming molded product. Even if it is flat, when the mold 21 is core-backed, the end face of the tip thick portion 53 can be raised to form the bead 55. That is, the bead 55 can be formed without forming the bead groove in the forming die 21, and the mold manufacturing cost of the forming die 21 can be suppressed. Further, by reducing the portion of the side wall 52 other than the front end edge (side wall main portion 54) thinner than the front end edge (front end thick portion 53), the engine cover 50 is reduced in weight and the resin composition as a raw material is reduced. Can be achieved.

  Further, the engine cover 50 according to the present embodiment is formed by increasing the thickness of the tip thick portion 53 on the inside of the side wall 52, so that the tip thick portion 53 is increased as compared with the case of increasing the thickness on the outside of the side wall 52. Can be made inconspicuous. Furthermore, since the tip thick portion 53 is formed by increasing the thickness so that the thickness gradually increases from the position closer to the tip of the side wall 52 toward the tip, formation of a step due to the increase in thickness can be avoided. It is possible to prevent the meat part 53 from being caught on the article or the touch.

[Molding experiment]
A molding experiment was conducted in order to examine the relationship between the width of the front end surface of the side wall 52 before the mold 21 was core-backed (see “c3” in FIG. 5) and the bead 55 formed after the core back. Specifically, a mold 21 having a cavity 24 in which the width of the front end surface of the side wall 52 before the core back is 2.0 [mm], 2.2 [mm], and 2.4 [mm] is prepared. The engine cover 50 was molded by the core back type foamed resin molding method described above using each mold 21. And the front end surface of the side wall 52 in the engine cover 50 after shaping | molding was observed. 7 to 9 are enlarged photographs of the leading edge of the side wall 52 after molding, and FIG. 10 is a conceptual diagram for comparing the leading edge of the side wall 52.

  As shown by the photograph in FIG. 7 and the solid line in FIG. 10, when the width of the front end surface of the side wall 52 before the core back is 2.0 [mm], the formation of the bead on the front end surface of the side wall 52 after molding is as follows. I was not able to admit. As shown by the photograph in FIG. 8 and the dotted line in FIG. 10, when the width of the front end surface of the side wall 52 before core back is 2.2 [mm], a bead is formed on a part of the front end surface of the side wall 52 after molding. Formation of 55 was observed. Further, as shown by the photograph in FIG. 9 and the two-dot chain line in FIG. 10, when the width of the front end surface of the side wall 52 before core back is 2.4 [mm], the entire front end surface of the side wall 52 after molding is formed. The formation of a rim 55 having a relatively large protrusion was observed.

  As is apparent from the experimental results, when the width of the front end face of the side wall 52 before the core back (see “c3” in FIG. 5) is 2.2 [mm] or more, preferably 2.4 [mm] or more, It has been found that the bead 55 can be formed without forming a bead groove in the mold 21.

[Other Embodiments]
The present invention is not limited to the above-described embodiment. For example, the embodiments described below are also included in the technical scope of the present invention, and various other than the following can be made without departing from the scope of the invention. It can be changed and implemented.

  (1) In the above-described embodiment, the engine cover 50 covering the upper surface of the engine is exemplified as the “container-like foamed product” according to the present invention, but the engine undercover, the timing belt cover, the oil pan, which covers the lower surface of the engine, A cover, a tray, a cap, a housing, and the like that are not limited to interior panels and other automobile parts may be used.

  (2) In the above-described embodiment, the distal end edge of the side wall 52 is increased inward to form the distal end thick portion 53. However, as shown in FIGS. The distal end edge may be thickened outward to form the distal end thick portion 53. In this case, as shown in FIGS. 10A and 10B, the distal end thick portion 53 is formed by increasing the thickness so that the thickness gradually increases from the position closer to the distal end of the side wall 52 toward the distal end. Alternatively, as shown in FIG. 5C, the thickness may be increased so that the thickness increases stepwise at a position near the tip of the side wall 52.

  (3) In the above-described embodiment, the side wall 52 is inclined with respect to the opening / closing direction of the mold 21 so as to expand from the main plate wall 51 toward the leading edge, but FIG. 10B and FIG. ), The side wall 52 may be parallel to the opening / closing direction of the mold 21. Further, the side wall 52 may be curved or bent between the main plate wall 51 and the leading edge.

20 Core Back Type Foamed Resin Molding Machine 21 Core Back Type Foamed Resin Mold 22D Stepped Surface 24 Cavity 24A Side Wall Main Molded Part 24B Thick Molded Part 50 Engine Cover (Container Foam Molded Product)
52 Side Wall 53 Tip Thick Part 54 Side Wall Main Part 55 Ball Edge

Claims (9)

A container-like foam molded article (50) that is foam-molded by a core-back foam molding method,
The tip end surface of the side wall (52) is provided on the entire tip edge of the side wall (52) with a tip thick part (53) that is thicker than the portion other than the tip edge, and is also the end face of the tip thick part (53). A container-like foamed molded article (50), characterized in that a rim (55), which is a rounded protrusion, is formed.   The container-like foamed molded product (50) according to claim 1, characterized in that the leading edge of the side wall (52) is thickened inward to form the thickened tip (53).   The tip thick portion (53) is formed by increasing the thickness so that the thickness gradually increases from a position closer to the tip of the side wall (52) toward the tip. Container-like foamed molded product (50).   The thickness (t2) of the portion other than the tip edge of the side wall (52) is 1.5 to 3.0 [mm], and the thickness (t3) of the tip thick portion (53) is: The container-like foamed molded article (50) according to any one of claims 1 to 3, wherein the container-shaped foamed article (50) is 2.2 to 3.0 [mm]. A core-back type foamed resin mold (21) for foam-molding a container-like foam-molded product (50),
A thick molded part (24B) for forming a thick tip part (53) thicker than a part other than the tip edge is provided on the entire tip edge of the side wall (52) of the container-like foam molded product (50). With
A core back type characterized in that a ball edge (55), which is a rounded protrusion, can be formed on the front end surface of the side wall (52) which is also an end surface of the thick end portion (53) by the core back. Foamed resin mold (21). The outer molding surface (23S) for molding the outer surface of the side wall (52) in the thick molded portion (24B) is inclined with respect to the opening / closing direction of the core back type foamed resin molding die (21). ,
The inner molding surface (22S) for molding the inner surface of the side wall (52) in the thick molded portion (24B) is parallel to the opening / closing direction of the core back type foamed resin molding die (21). The core back type foaming resin mold (21) according to claim 5, characterized by the above.   The width (c2) of the cavity (24) in the side wall main body molding portion (24A) for molding a portion other than the tip edge of the side wall (52) is less than 2.0 [mm] in the state before the core back. The width (c3) of the cavity (24) at the end face of the thick molded part (24B) is configured to be 2.2 [mm] or more in the state before the core back. 5. A core-back type foamed resin mold (21) according to 5 or 6. In the core-back type foamed resin molding method in which the container-like foamed molded article (50) is foam-molded by filling the cavity (24) of the core-back-type foamed resin mold (21) with the molten resin and then performing the core back. ,
A thick molding part (24B) for molding a tip thick part (53) thicker than a part other than the tip edge over the entire tip edge of the side wall (52) of the container-like foam molded product (50), Provided in the cavity (24), by means of the core back, a bead (55) which is a rounded protrusion on the front end surface of the side wall (52) which is also an end surface of the thick end portion (53). A core back type foamed resin molding method characterized by forming.   The width (c2) of the cavity (24) in the side wall main molding part (24A) for molding a part other than the tip edge of the side wall (52) is less than 2.0 mm, and the thick molding is performed. The width (c3) of the cavity (24) at the end face of the portion (24B) is set to 2.2 [mm] or more, and the cavity (24) is filled with the molten resin. 9. A core back type foamed resin molding method according to 8.