JP5782876B2 - Mold structure for molding foamed resin molded products - Google Patents

Description

  The present invention relates to a mold structure for molding a foamed resin molded article, and in particular, a skin layer which is a surface layer by filling the cavity with a foamed resin in a molten state and the skin layer The present invention relates to a mold structure for molding a foamed resin molded product in which a foamed resin molded product having a foamed layer provided inside is molded, and then a part of the skin layer is peeled to expose the foamed layer.

  Conventionally, in the field of various industrial parts such as automobile parts, foamed resin molded articles having excellent characteristics such as lightness, heat insulation and soundproofing have been widely adopted. Such a foamed resin molded product is molded by selecting a suitable material for use according to the purpose and application to be used, and by suitably setting various conditions such as the form of bubbles inside the molded product and the expansion ratio. ing.

  As a method of molding such a foamed resin molded product, after filling a foamable resin containing a foaming agent into the resin into a mold composed of a fixed mold and a movable mold, the movable mold is moved in the mold opening direction to form a cavity. A molding method (so-called core back method) is known in which foaming of a foamable resin is promoted by enlarging the volume of the foamed resin.

  The foamed resin molded product molded by such a molding method is a non-foamed skin layer which is a surface layer on the surface of the foamed resin molded product by cooling the foamable resin filled in the mold from the surface by the mold. And a foamed layer in which foaming of the foamable resin is promoted is formed inside the skin layer.

  When the foamed resin molded product molded in this way is used as a heat insulating material or a soundproofing material, the heat insulating effect and the soundproofing effect are lowered by the skin layer formed on the surface of the foamed resin molded product. In order to effectively obtain a soundproofing effect, it is desirable to remove the skin layer formed on the surface.

  Although it does not remove the skin layer in order to prevent the heat insulation effect and the soundproofing effect from decreasing, for example, in Patent Document 1, after laminating the adhesive sheet on the surface of the foam, it is on the side opposite to the adhesive sheet. A structure in which the entire skin layer formed on the foam surface is removed by slicing with a slicing blade is disclosed.

JP-A-6-344459

  As described in Patent Document 1, by removing the entire skin layer formed on the surface by slicing, the foamed layer can be exposed to effectively obtain a heat insulating effect and a soundproofing effect in the foamed resin molded product. However, if the entire skin layer is removed, the strength of the foamed resin molded product is greatly reduced.

  On the other hand, by exfoliating a part of the skin layer formed on the surface after molding the foamed resin molded product and exposing the foamed layer, the heat insulating effect is suppressed while suppressing the strength of the foamed resin molded product from decreasing. It is considered that a soundproofing effect can be obtained effectively.

  As a method of peeling off a part of the skin layer formed on the surface in this way and exposing the foam layer, the main body part and the rib part of the foamed resin molded product are integrally formed, and then the rib part is broken. By doing so, it is conceivable that the skin layer of the main body portion continuous to the rib portion is peeled to expose the foam layer.

  FIG. 10 is an explanatory view for explaining a method of peeling a part of the skin layer in the foamed resin molded product to expose the foamed layer, and FIG. 10 (a) is a diagram illustrating a main body and ribs of the foamed resin molded product. FIG. 10B shows a state in which the rib portion is broken to expose the foam layer of the main body portion of the foamed resin molded product.

  As shown in FIG. 10A, a main body portion 101 having a non-foamed skin layer 102 formed on the surface and a foam layer 103 provided inside the skin layer 102, and a surface of the main body portion 101. After molding the foamed resin molded product 100 integrally formed with the non-foamed rib portion 105 erected on the skin layer, a predetermined folding force F1 is applied to the rib portion 105 from the outside, As shown in FIG. 10B, the skin layer 102 of the main body portion 101 continuous with the rib portion 105 is peeled off together with the rib portion 105, and an opening 102a is formed in the skin layer 102 to expose the foam layer 103. It is possible to make it.

  FIG. 11 is an explanatory diagram for explaining a method of integrally forming the main body portion and the rib portion of the foamed resin molded product, and FIG. 11 (a) is a diagram illustrating a mold including a fixed mold and a movable mold. FIG. 11 (b) shows a state where the movable mold is moved in the mold opening direction after filling the cavity with the foamable resin.

  A foamed resin molded article 100 shown in FIG. 10A has a cavity 110a formed by the fixed mold 111 and the movable mold 121 and a concave shape on the cavity molding surface 111a of the fixed mold 111, as shown in FIG. 11B is used after filling the cavity 110a of the mold 110 with the foamable resin 131 in a molten state through the injection path 116, using the mold 110 provided with the rib-shaped molding part 111b formed in FIG. As described above, the movable mold 121 can be moved in the mold opening direction (the direction indicated by the arrow X1) so as to increase the volume of the cavity 110a to promote foaming of the foamable resin 131.

  FIG. 12 is an explanatory diagram for explaining a state in which the rib portion of the foamed resin molded product is broken. In order to break the rib portion 105 in the foamed resin molded product 100 molded as shown in FIG. 11, the rib portion 105 is substantially in the standing direction of the rib portion 105 as shown in FIG. When a predetermined falling force F1 is applied from the outside in the orthogonal direction, as shown in FIG. 12 (b), the rib portion 105 is inclined in the direction in which the falling force F1 is applied, and then shown in FIG. 12 (c). As described above, the rib portion 105 is broken, and a part of the skin layer 102 of the main body portion 101 can be peeled to expose the foam layer 103.

  However, when part of the skin layer 102 is peeled and the foamed layer 103 is exposed in this way, as shown in FIGS. 12B and 12C, the inclining force acting surface portion 107 of the rib portion 105 is used. A part of the foam layer 103 is crushed by the surface portion 108 on the opposite side, and the strength of the foamed resin molded product 100 may be reduced.

  Moreover, FIG. 13 is explanatory drawing for demonstrating another state which removed the rib part of the foamed resin molded product. As shown in FIG. 12A, when a predetermined falling force F1 is applied to the rib portion 105 of the foamed resin molded product 100 from the outside, the falling force acting surface portion 107 of the rib portion 105 is shown in FIG. There is a possibility that the skin layer 102 of the main body 101 that is continuous in the direction in which the falling force F1 is applied to the surface 108 on the opposite side is largely peeled together with the ribs 105 and the strength of the foamed resin molded product 100 is lowered.

  Therefore, the present invention provides a gold for molding a foamed resin molded product that can mold a foamed resin molded product in which a foamed layer is exposed by peeling a part of the skin layer while suppressing a decrease in strength of the foamed resin molded product. The object is to provide a mold structure.

For this reason, the invention according to claim 1 of the present application includes a mold having a cavity for molding a foamed resin molded article and capable of expanding the volume of the cavity, and the foamable resin in a molten state is provided with the mold. After filling the cavity, the volume of the cavity is expanded to form a foamed resin molded article having a skin layer as a surface layer and a foam layer provided inside the skin layer, and then a part of the skin layer Is a mold structure for molding a foamed resin molded product so as to expose the foamed layer, wherein the mold is a main body molding part for molding the main body part of the foamed resin molded product, A rib part molding part for molding a rib part standing on the surface of the main body part, and the rib part molding part is formed in an undercut shape with respect to the standing direction of the rib part. To mold the rib part The mold is formed in a state in which the rib portion is held by the rib portion molding portion when the foamed resin molding product is taken out after the foam resin molding product having the main body portion and the rib portion is molded. The rib portion and the main body portion are separated from each other in the standing direction of the rib portion, so that the skin layer of the main body portion continuous with the rib portion is peeled to expose the foam layer of the main body portion. The mold includes a main body part that forms the cavity and a core part that is movably inserted into an opening provided in the main body part, and the rib part molding part is provided in the core part. It is formed by a groove for molding the provided rib part and an opening of the main body part, and the core part is moved by moving the core part after separating the rib part and the main body part of the foamed resin molded product. Molded by the opening of the main body And it is configured to expose the molding surface of the rib portion, characterized in that.

  The invention according to claim 2 of the present application is the invention according to claim 1, wherein the mold includes a projecting member for projecting a main body portion of the foamed resin molded product from the main body portion molding portion, and the foam resin. When the molded product is taken out, the main body part is projected from the main body part molding part by the projecting member in a state where the rib part is held in the rib part molding part so that the rib part and the main body part are separated from each other. It is comprised in that.

According to the invention according to claim 1 of the present application, the mold is for molding a main body portion molding portion for molding the main body portion of the foamed resin molded product and a rib portion standing on the surface of the main body portion. A rib part molding part, and the rib part molding part is formed so as to mold a rib part formed in an undercut shape with respect to the standing direction of the rib part. When molding a foamed resin molded product having a rib portion, the rib portion and the main body portion are separated from each other in the standing direction of the rib portion in a state where the rib portion is held in the rib portion molding portion. The skin layer of the main body portion is peeled off to expose the foam layer of the main body portion, and the mold includes a main body portion forming a cavity and a core portion inserted into an opening provided in the main body portion. And the rib part molding part is formed in the groove part provided in the core part and the opening part of the main body part. It formed me, and is configured to expose the molding surface of the rib portion by moving the core portion after being separated from the rib portion and the body portion of the foamed resin molded article. Accordingly, a mold having a relatively simple structure can be used to peel a part of the skin layer of the foamed resin molded product to expose the foamed layer, and the skin while suppressing a decrease in strength of the foamed resin molded product. A foamed resin molded article in which a part of the layer is peeled to expose the foamed layer can be molded.

  According to the invention of claim 2 of the present application, the mold is provided with a projecting member for projecting the main body part of the foamed resin molded product from the main body part molding part, and when the foamed resin molded product is taken out, the rib part molding is performed. In a state where the rib portion is held in the portion, the main body portion is protruded from the main body portion molding portion by the protruding member, and the rib portion and the main body portion are separated from each other. Thereby, when taking out the foamed resin molded product, the rib portion and the main body portion can be separated from each other, so that the above-described effect can be obtained without extending the molding cycle time for molding the foamed resin molded product. it can.

It is a schematic explanatory drawing which shows the shaping | molding apparatus provided with the metal mold | die which concerns on the 1st Embodiment of this invention. It is a cross-sectional explanatory view for explaining a method of forming a main body portion and a rib portion of a foamed resin molded product in the mold shown in FIG. FIG. 2 is an explanatory cross-sectional view for explaining a method of separating a main body portion and a rib portion of a foamed resin molded product in the mold shown in FIG. 1. It is sectional explanatory drawing which shows the metal mold | die which concerns on the 2nd Embodiment of this invention. FIG. 5 is an explanatory cross-sectional view for explaining a method of forming the main body portion and the rib portion of the foamed resin molded product in the mold shown in FIG. 4. FIG. 5 is an explanatory cross-sectional view for explaining a method of separating the main body portion and the rib portion of the foamed resin molded product in the mold shown in FIG. 4. It is a section explanatory view showing a metallic mold concerning a 3rd embodiment of the present invention. FIG. 8 is an explanatory cross-sectional view for explaining a method of forming the main body portion and the rib portion of the foamed resin molded product in the mold shown in FIG. 7. FIG. 8 is an explanatory cross-sectional view for explaining a method of separating the main body portion and the rib portion of the foamed resin molded product in the mold shown in FIG. 7. It is explanatory drawing for demonstrating the method to peel a part of skin layer and to expose a foam layer in a foamed resin molded product. It is explanatory drawing for demonstrating the method to form the main-body part and rib part of a foamed resin molded product integrally. It is explanatory drawing for demonstrating the state which fractured the rib part of the foamed resin molded product. It is explanatory drawing for demonstrating another state which broke the rib part of the foamed resin molded product.

Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings.
FIG. 1 is a schematic explanatory view showing a molding apparatus provided with a mold according to the first embodiment of the present invention. As shown in FIG. 1, a molding apparatus M including a mold according to the first embodiment of the present invention is for molding a foamed resin molded product. 10 includes an injection device 30 for injecting a foamed resin in a molten state.

  The mold 10 includes a fixed mold 11 and a movable mold 21. By closing the fixed mold 11 and the movable mold 21, a cavity 10a for forming a foamed resin molded product is formed in the mold 10. It has become so. The fixed mold 11 has a cavity molding surface 11a and an injection path 16 for injecting a foamable resin from the injection device 30 into the cavity 10a.

  On the other hand, the movable die 21 has a body portion 22 that has a cavity molding surface 22a and is combined with the fixed die 11. The body portion 22 has a substantially rectangular cross section in the opening / closing direction of the mold 10 (direction indicated by the arrow X2). An opening 22b formed in a shape is provided, and a hole 22c formed in a substantially circular cross section in the opening / closing direction of the mold 10 is provided.

  A core portion 23 formed in a substantially rectangular cross section is inserted into the opening portion 22b of the main body portion 22 so as to be movable in the opening and closing direction of the mold 10, and the hole portion 22c of the main body portion 22 has a substantially circular cross section. A pin portion 24 as a protruding member to be formed is inserted so as to be movable in the opening / closing direction of the mold 10. In addition, each of the pin portions 24 is coupled to the pin portion holding plate 25 and provided at least in the vicinity of the core portion 23.

  The core part 23 and the pin part 24 of the movable mold 21 have cavity molding surfaces 23a and 24a, respectively, and the cavity molding surface 23a of the core part 23 is recessed in a substantially L-shaped cross section as shown in FIG. A groove 23b to be formed is provided. The groove part 23b of the core part 23 extends in a direction substantially orthogonal to the opening / closing direction of the mold 10, and extends from the vertical wall part 23c in the opening / closing direction of the mold 10 and forms an acute angle with the vertical wall part 23c. The horizontal wall portion 23d is formed.

  In the present embodiment, the foamed resin molded product is obtained by integrally forming the main body portion and the rib portion of the foamed resin molded product after the main body portion having a product shape and the rib portion standing on the surface of the main body portion are integrally formed. Therefore, the rib part molding part 10b for molding the rib part of the foamed resin molded product is formed by the groove part 23b of the core part 23 and the opening part 22b of the main body part 22 extending in the opening and closing direction of the mold 10. The rib portion forming portion 10b is formed so as to shape the rib portion formed in an undercut shape with respect to the standing direction of the rib portion. Here, the undercut shape refers to a shape that cannot be released in the standing direction of the rib portion when taking out the foamed resin molded product.

  On the other hand, the main body part molding part 10c for molding the main body part of the foamed resin molded product is composed of a cavity molding surface 22a of the main body part 22, a cavity molding surface 23a of the core part 23, and a cavity molding surface 24a of the pin part 24. It is formed by a main body molding part on the side and a main body molding part on the fixed side composed of the cavity molding surface 11 a of the fixed mold 11. The cavity molding surface 22a that constitutes the main body molding portion 10c includes a step portion 22d that is recessed in an L-shaped cross section at the peripheral edge, and the main body molding portion 10c is the peripheral edge of the main body portion of the foamed resin molded product. It is comprised so that a vertical wall part can be formed.

  The mold 10 is also configured such that the main body portion 22, the core portion 23, and the pin portion 24 of the movable mold 21 are integrally movable in the opening / closing direction of the mold 10 with respect to the fixed mold 11. After the mold 21 is closed, the volume of the cavity 10a can be increased by moving the movable mold 21 in the mold opening direction of the mold 10. The core part 23 and the pin part 24 of the movable mold 21 are configured to be movable in the opening / closing direction of the mold 10 with respect to the main body part 22.

  On the other hand, the injection device 30 is for injecting a molten foamable resin 31 into the cavity 10a of the mold 10 and includes a cylinder 33 for kneading and melting the resin 32. A screw 34 is provided inside the cylinder 33. ing. A screw drive mechanism and an injection mechanism (both not shown) are connected to the rear end of the screw 34.

  The injection device 30 is configured to sequentially heat and knead and melt the resin 32 put into the cylinder 33 by a heater (not shown) and a screw 34 provided around the cylinder 33. Then, the inert gas made supercritical through the supercritical fluid generator 36 from a cylinder 35 containing an inert gas such as carbon dioxide or nitrogen is injected into the kneaded and melted resin 32 through supercritical fluid injection. A foamable resin 31 that is injected by the device 37 and contains a foaming agent in the resin 32 is formed.

  The foamable resin 31 in the cylinder 33 is injected into the cavity 10a of the mold 10 by the screw 34 being rotated by the screw drive mechanism and injected by the injection mechanism.

  In the present embodiment, as the resin 32, for example, a thermoplastic resin such as a polypropylene resin is used. Moreover, in this embodiment, although the fluid in a supercritical state is used as a physical foaming agent for the foaming agent contained in the foamable resin 31, other physical foaming agents may be used. Alternatively, chemical blowing agents can be used.

  Although not specifically illustrated, the molding apparatus M includes a control unit that comprehensively controls the molding apparatus M. The control unit is configured with, for example, a microcomputer as a main part, and is configured to perform various controls such as operation control of the mold 10 and operation control of the injection device 30.

Next, molding of a foamed resin molded product using the molding apparatus M will be described.
As shown in FIG. 1, in a state where the mold 10 is closed, a foamable resin 31 containing a resin 32 containing a supercritical fluid as a foaming agent is injected into the cavity 10 a of the mold 10 from the injection device 30. After the molten foamable resin 31 is filled in the cavity 10a, the movable mold 21 is moved in the mold opening direction so as to increase the volume of the cavity 10a.

  FIG. 2 is a cross-sectional explanatory view for explaining a method of forming the main body portion and the rib portion of the foamed resin molded product in the mold shown in FIG. 1, and FIG. 2 (a) shows a foamable resin in the cavity 10a. FIG. 2B shows a state in which the movable mold 21 is moved in the mold opening direction after the cavity 10a is filled with the foamable resin 31. FIG.

  As shown in FIG. 2A, after the cavity 10a of the mold 10 is filled with the foamable resin 31 through the injection path 16, the volume of the cavity 10a is expanded as shown in FIG. The movable mold 21 is moved in the mold opening direction (direction indicated by the arrow X3) to promote foaming of the foamable resin 31.

  When the movable mold 21 is moved in the mold opening direction, a main body portion 41 having a product shape and a rib portion 45 erected on the surface of the main body portion 41 in a substantially quadrangular prism shape in a direction substantially perpendicular to the surface. The foamed resin molded product 40 is formed, and the rib portion 45 is formed in an undercut shape with respect to the standing direction of the rib portion 45. The main body portion 41 of the foamed resin molded product 40 is molded by the main body portion molded portion 10c, and the rib portion 45 of the foamed resin molded product 40 is molded by the rib portion molded portion 10b.

  In the foamed resin molded product 40, the main body 41 is formed by a non-foamed skin layer 42 whose surface is a surface layer, and foaming of the foamable resin 31 is promoted inside the skin layer 42. The layer 43 is formed, and the rib portion 45 is formed in a non-foamed state. In addition, the vertical wall part 44 is formed in the peripheral part in the main-body part 41 of the foamed resin molded product 40, and this vertical wall part 44 is formed in the non-foamed state.

  When the foamed resin molded product 40 having the main body portion 41 and the rib portion 45 is molded as described above and then taken out, the movable mold 21 is moved in the mold opening direction so that the mold 10 is molded. The main body that is opened and then continues to the rib portion 45 by separating the rib portion 45 and the main body portion 41 in the standing direction of the rib portion 45 in a state where the rib portion 45 is held in the rib portion molding portion 10b. The skin layer 42 of the portion 41 is peeled off to expose the foam layer 43.

  FIG. 3 is a cross-sectional explanatory diagram for explaining a method of separating the main body portion and the rib portion of the foamed resin molded product in the mold shown in FIG. 1, and FIG. 3 (a) shows the mold opened. FIG. 3B shows a state in which the pin portion protrudes from the movable main body portion, and FIG. 3C shows the state in which the core portion is moved relative to the movable main body portion. Indicates the state.

  As shown in FIG. 3A, when the foamed resin molded product 40 is taken out and then taken out, the main body 22, the core 23 and the pin 24 are integrated into the movable die 21 in the mold opening direction (indicated by the arrow X3). The mold 10 is opened, and the entire foamed resin molded product 40 is moved together with the movable die 21 with the rib portion 45 held by the rib portion molding portion 10b.

  When the mold 10 is opened, next, as shown in FIG. 3 (b), the pin portion 24 with respect to the main body portion 22 of the movable die 21 with the rib portion 45 held in the rib portion molding portion 10 b. Projecting in the mold closing direction of the mold 10 (the direction indicated by the arrow X4), which is the direction in which the rib portion 45 is erected, to form the main body molding portion 10c, specifically, the main body molding portion on the movable side The main body portion 41 of the foamed resin molded product 40 protrudes from the cavity molding surface 22a of 22 and the cavity molding surface 23a of the core portion 23 in the standing direction of the rib portion 45.

  When the main body portion 41 of the foamed resin molded product 40 is protruded, the rib portion 45 of the foamed resin molded product 40 is formed in an undercut shape in the direction in which the rib portion 45 is erected, and thus is held by the rib portion molded portion 10b. In this state, the skin layer 42 of the main body portion 41 continuous with the rib portion 45 is peeled together with the rib portion 45, and an opening 42 a is formed in the skin layer 42 of the main body portion 41 to expose the foam layer 43.

  The main body portion 41 of the foamed resin molded product 40 is also protruded by the pin portion 24 and dropped from the mold 10, and the foamed resin molded product 40 is taken out. It is also possible to take it out from. In this way, using the mold 10, it is possible to manufacture a foamed resin molded product 40 in which a part of the skin layer 42 is peeled and the foamed layer 43 is exposed.

  After the foamed resin molded product 40 is manufactured, as shown in FIG. 3C, the core portion 23 is moved in the mold closing direction of the mold 10 (the direction indicated by the arrow X4), thereby forming the rib portion molded portion 10b. The rib portion 45 held in the mold is dropped and removed from the mold 10, but it is also possible to reliably drop the rib portion 45 by blowing air (air) to the rib portion molding portion 10b. It is.

  In the present embodiment, the rib portion 45 of the foamed resin molded product 40 is formed in a substantially quadrangular prism shape and is formed in an undercut shape with respect to the standing direction of the rib portion 45, but the rib portion is substantially circular. The rib portion is formed in a columnar shape and in other shapes in which the rib portion is formed in an undercut shape with respect to the standing direction of the rib portion. Is also possible.

  As described above, the mold structure for molding the foamed resin molded product according to the present embodiment includes the cavity 10a for molding the foamed resin molded product 40 and the mold 10 configured so that the volume of the cavity 10a can be expanded. A foamed resin having a skin layer 42 as a surface layer and a foam layer 43 provided inside the skin layer 42 by enlarging the volume of the cavity 10a after filling the meltable foamable resin 31 into the cavity 10a The molded product 40 is molded, and then the skin layer 42 is partially peeled to expose the foamed layer 43.

  In particular, the mold 10 includes a main body portion molding portion 10c for molding the main body portion 41 of the foamed resin molded product 40 and a rib portion molding portion for molding the rib portion 45 standing on the surface of the main body portion 41. 10b, and the rib portion forming portion 10b is formed so as to shape the rib portion 45 formed in an undercut shape with respect to the standing direction of the rib portion 45. When the foamed resin molded product 40 having the rib portions 45 is molded and then taken out, the rib portions 45 are arranged in the standing direction of the rib portions 45 in a state where the rib portions 45 are held in the rib portion molded portions 10b. By separating the main body 41 from the main body 41, the skin layer 42 of the main body 41 continuing to the rib 45 is peeled off to expose the foam layer 43 of the main body 41.

  As a result, the mold 10 having a relatively simple configuration can be used to peel a part of the skin layer 42 of the foamed resin molded product 40 to expose the foamed layer 43, thereby reducing the strength of the foamed resin molded product 40. The foamed resin molded product 40 in which a part of the skin layer 42 is peeled off and the foamed layer 43 is exposed can be molded.

  In addition, the mold 10 includes a protruding member 24 that protrudes the main body 41 of the foamed resin molded product 40 from the main body molded portion 10c. When the foamed resin molded product 40 is taken out, the rib portion 45 is formed on the rib portion molded portion 10b. The main body 41 is protruded from the main body molding portion 10c by the projecting member 24 in a state in which the rib 45 and the main body 41 are separated from each other.

  Thereby, since the rib part 45 and the main-body part 41 can be spaced apart when taking out the foamed resin molded product 40, the said effect is achieved, without extending the molding cycle time for shape | molding the foamed resin molded product 40. Can be obtained.

  FIG. 4 is a cross-sectional explanatory view showing a mold according to the second embodiment of the present invention. The mold according to the second embodiment of the present invention is the mold 10 according to the first embodiment of the present invention, wherein the fixed mold is provided with the rib portion molding portion and the fixed mold is provided with the fixed mold mounting plate. In addition, the movable mold is not provided with a core, and the same reference numerals are given to the same components as those of the mold 10 according to the first embodiment of the present invention, and the description thereof is omitted.

  As shown in FIG. 4, the mold 50 according to the second embodiment of the present invention further includes a fixed mold mounting plate 52 that is superposed on the fixed mold 51 in addition to the fixed mold 51 and the movable mold 61, and includes a fixed mold. 51, the movable mold 61 and the fixed mold mounting plate 52 are closed together to form a cavity 50a for molding a foamed resin molded product in the mold 50.

  The fixed mold 51 has a cavity molding surface 51a, and a plurality of grooves 51b formed in the cavity molding surface 51a so as to be recessed in a substantially rectangular cross section in the opening / closing direction of the mold 50 (direction indicated by the arrow X2). The groove 51b is formed so as to open to the end surface 51c of the fixed mold 51.

  The groove 51b of the fixed mold 51 includes an upper wall 51d extending in the opening / closing direction of the mold 50 and a lower wall 51e extending in the opening / closing direction of the mold 50 and inclined downward toward the fixed mold mounting plate 52 side. In addition, the upper wall 51d and the lower wall 51e are provided with side walls (not shown) on the front and back surfaces of the drawing.

  In the mold 50, a rib portion molding portion 50b for molding a rib portion of a foamed resin molded product is formed by the groove portion 51b of the fixed die 51 and the end surface 52a of the fixed die mounting plate 52. The rib portion formed in an undercut shape with respect to the standing direction of the rib portion is formed.

  In the present embodiment, the stationary mold 51 is configured to be movable in the opening / closing direction of the mold 50 with respect to the stationary mold mounting plate 52. Each of the fixed mold 51 and the fixed mold mounting plate 52 is provided with an injection path 16 for injecting a foamable resin from the injection device 30 into the cavity 50a.

  On the other hand, the movable mold 61 includes a main body 22 having a cavity molding surface 22a and combined with the fixed mold 51. The main body 22 has a hole formed in a substantially circular cross section in the opening and closing direction of the mold 50. 22c is provided, and a pin portion 24 as a protruding member formed in a substantially circular cross section is inserted into the hole portion 22c so as to be movable in the opening and closing direction of the mold 50.

  In the mold 50, the main body molding portion 50c for molding the main body portion of the foamed resin molded product is a movable main body molding composed of the cavity molding surface 22a of the main body portion 22 and the cavity molding surface 24a of the pin portion 24. And a fixed-side main body forming part formed of the cavity forming surface 51 a of the fixed mold 51. The cavity molding surface 22a constituting the main body part molding part 50c includes a step part 22d that is recessed in an L-shaped cross section at the peripheral part thereof, and the main body part molding part 50c is a peripheral part of the main body part of the foamed resin molded product. It is comprised so that a vertical wall part can be formed.

  Also in the mold 50, the main body portion 22 and the pin portion 24 of the movable mold 61 can be integrally moved in the opening / closing direction of the mold 50 with respect to the fixed mold 51. By moving the movable mold 61 in the mold opening direction of the mold 50 after closing, the volume of the cavity 50a can be expanded. The pin portion 24 of the movable mold 61 is configured to be movable in the opening / closing direction of the mold 50 with respect to the main body portion 22.

  Even when the mold 50 configured as described above is used, the foamable resin 31 is injected from the injection device 30 into the cavity 50a with the mold 50 closed as shown in FIG. After the foamable resin 31 is filled in the cavity 50a, the movable mold 61 is moved in the mold opening direction so as to increase the volume of the cavity 50a.

  FIG. 5 is a cross-sectional explanatory view for explaining a method of forming the main body portion and the rib portion of the foamed resin molded product in the mold shown in FIG. 4. As shown in FIG. 5, when the movable mold 61 is moved in the mold opening direction (the direction indicated by the arrow X3) after the foamable resin 31 is filled in the cavity 50a, the main body 71 having a product shape, and the main body A foamed resin molded product 70 having a rib portion 75 standing in a substantially quadrangular prism shape in a direction substantially orthogonal to the surface is formed on the surface of the portion 71, and the rib portion 75 is formed with respect to the standing direction of the rib portion 75. It is formed in an undercut shape. The main body portion 71 of the foamed resin molded product 70 is molded by the main body portion molded portion 50c, and the rib portion 75 of the foamed resin molded product 70 is molded by the rib portion molded portion 50b.

  Further, in the foamed resin molded product 70, the main body 71 is formed by a non-foamed skin layer 72 whose surface is a surface layer, and foaming of the foamable resin 31 is promoted inside the skin layer 72. The layer 73 is formed, and the rib portion 75 is formed in a non-foamed state. The main body 71 of the foamed resin molded product 70 has a vertical wall 74 formed at the peripheral edge thereof, and the vertical wall 74 is formed in a non-foamed state.

  In this way, when the foamed resin molded product 70 having the main body portion 71 and the rib portion 75 is molded and then taken out, the movable mold 61 is moved in the mold opening direction so that the mold 50 is molded. In a state where the rib portion 75 is held in the rib portion molding portion 50b and the rib portion 75 and the main body portion 71 are separated in the standing direction of the rib portion 75, the main body portion 71 continuous to the rib portion 75 is separated. The skin layer 72 is peeled off to expose the foam layer 73.

  6 is a cross-sectional explanatory view for explaining a method of separating the main body portion and the rib portion of the foamed resin molded product in the mold shown in FIG. 4, and FIG. 6 (a) shows the mold opened. FIG. 6 (b) shows a state in which the pin portion protrudes from the movable body portion, and FIG. 6 (c) shows a state in which the fixed die is moved relative to the fixed die mounting plate. Is shown.

  As shown in FIG. 6A, when the foamed resin molded product 70 is molded and taken out, the movable die 61 is moved in the die opening direction (direction indicated by the arrow X3) with the main body portion 22 and the pin portion 24 integrated. Then, the mold 50 is opened, and the main body 71 of the foamed resin molded product 70 is moved together with the movable die 61 in a state where the rib portion 75 is held by the rib portion molding portion 50b. The main body 71 is provided with a vertical wall 74 at the periphery thereof, and is formed to be held by the movable die 61 when the movable die 61 is moved.

  When the main body portion 71 of the foamed resin molded product 70 is moved together with the movable die 61, the rib portion 75 is formed in an undercut shape in the standing direction of the rib portion 75, and thus is held by the rib portion molding portion 50b. In this state, the skin layer 72 of the main body 71 continuous to the rib 75 is peeled from the main body 71 together with the rib 75, and an opening 72a is formed in the skin layer 72 of the main body 71 to expose the foam layer 73. .

  When the mold 50 is opened, next, as shown in FIG. 6B, the pin portion 24 is closed with respect to the main body portion 22 of the movable mold 61 (the direction indicated by the arrow X4). The body portion 71 of the foamed resin molded product 70 is moved in the opening / closing direction of the mold 50 from the cavity molding surface 22a of the body portion 22 constituting the body portion molding portion 50c, specifically the movable body portion molding portion. Thus, the main body 71 of the foamed resin molded product 70 falls from the mold 50 and the foamed resin molded product 70 is taken out. In this way, using the mold 50, it is possible to manufacture a foamed resin molded product 70 in which a part of the skin layer 72 is peeled and the foamed layer 73 is exposed.

  After the foamed resin molded product 70 is manufactured, as shown in FIG. 6C, the fixed mold 51 is moved to the movable mold 61 side (in the direction indicated by the arrow X5), and then held by the rib portion molding portion 50b. By blowing air from an air supply device (not shown) to the rib portion 75 that has been formed, the rib portion 75 falls from the mold 50 and is removed.

  As described above, even when the mold according to the second embodiment of the present invention is used, the mold 50 includes the body part molding part 50c for molding the body part 71 of the foamed resin molded product 70, and the body part. And a rib portion molding portion 50b for molding a rib portion 75 standing on the surface of 71, and the rib portion molding portion 50b is formed in an undercut shape with respect to the standing direction of the rib portion 75. The rib 50 is formed to mold the rib portion 75. When the mold 50 is taken out of the foamed resin molded product 70 having the main body portion 71 and the rib portion 75, the rib portion molded portion 50b is formed. The rib portion 75 and the main body portion 71 are separated from each other in the standing direction of the rib portion 75 while the rib portion 75 is held, thereby peeling the skin layer 72 of the main body portion 71 continuous with the rib portion 75. 71 so that the foam layer 73 of 71 is exposed. It is.

  As a result, the mold 50 having a relatively simple configuration can be used to peel a part of the skin layer 72 of the foamed resin molded product 70 to expose the foamed layer 73, thereby reducing the strength of the foamed resin molded product 70. It is possible to mold the foamed resin molded article 70 in which a part of the skin layer 72 is peeled and the foamed layer 73 is exposed while suppressing the above.

  In the mold 50 according to the second embodiment, the movable mold 61 may further include a core portion 23 similar to that of the mold 10 according to the first embodiment. By using such a mold, the foamed layer can be exposed on the surfaces on both sides of the main body of the foamed resin molded product.

  FIG. 7 is a cross-sectional explanatory view showing a mold according to the third embodiment of the present invention. The mold according to the third embodiment of the present invention is different from the mold 50 according to the second embodiment of the present invention in that the shape of the rib portion molding portion is different, and the mold according to the second embodiment. The same components as those in FIG.

  As shown in FIG. 7, a mold 80 according to the third embodiment of the present invention includes a fixed mold 81, a movable mold 61, and a fixed mold mounting plate 52, and the fixed mold 81, the movable mold 61, and the fixed mold mounting plate. By closing the mold 52, a cavity 80a for molding a foamed resin molded product is formed in the mold 80.

  The fixed die 81 has a cavity molding surface 81a, and a plurality of first groove portions 81b formed in the cavity molding surface 81a so as to be recessed in a substantially rectangular cross section in the opening / closing direction of the mold 80 (direction indicated by the arrow X2). Is provided. In the fixed die 81, a second groove portion is formed in the end surface 81c of the fixed die 81 so as to connect the plurality of first groove portions 81b so as to be recessed in a substantially rectangular shape in a direction substantially orthogonal to the opening / closing direction of the mold 80. 81d is provided.

  In the mold 80, the first groove portion 81b and the second groove portion 81d of the fixed mold 81 and the end surface 52a of the fixed mold mounting plate 52 form a rib portion molding portion 80b for molding the rib portion of the foamed resin molded product, The rib portion molding portion 80b is formed so as to mold a rib portion formed in an undercut shape with respect to the standing direction of the rib portion.

  Specifically, the rib portion molding portion 80b includes a plurality of rib portion main body portions extending in a direction substantially orthogonal to the surface of the main body portion of the foamed resin molded product, and a direction substantially orthogonal to the standing direction of the rib portion main body portion. A rib portion having a rib portion connecting portion that connects end portions of the plurality of rib portion main body portions to each other, and is formed in the standing direction of the rib portion, specifically, the rib portion main body portion. On the other hand, the rib portion formed in an undercut shape is formed.

  On the other hand, the main body molding part 80c for molding the main body part of the foamed resin molded product is fixed to the movable main body molding part composed of the cavity molding surface 22a of the main body part 22 and the cavity molding surface 24a of the pin part 24. The mold 81 is formed by a fixed-side main body molding portion comprising the cavity molding surface 81a of the mold 81.

  Even in the case of using the mold 80 configured as described above, the foamable resin 31 is injected from the injection device 30 into the cavity 80a with the mold 80 closed as shown in FIG. After the foamable resin 31 is filled in the cavity 80a, the movable mold 61 is moved in the mold opening direction so as to increase the volume of the cavity 80a.

  FIG. 8 is a cross-sectional explanatory view for explaining a method of forming the main body portion and the rib portion of the foamed resin molded product in the mold shown in FIG. As shown in FIG. 8, when the movable mold 61 is moved in the mold opening direction (the direction indicated by the arrow X3) after the cavity 80a is filled with the foamable resin 31, the main body portion 91 and the surface of the main body portion 91 are moved. A foamed resin molded product 90 having a rib portion 95 standing upright is formed. The rib portion 95 includes a plurality of rib portion main body portions 96 extending in a direction substantially orthogonal to the surface of the main body portion 91, and the rib portion main body. A rib portion connecting portion 97 that extends in a direction substantially orthogonal to the standing direction of the portion 96 and connects end portions of the plurality of rib portion main body portions 96, and includes a rib portion 95, specifically, the rib portion main body portion 96. It is formed in an undercut shape with respect to the standing direction. The main body portion 91 of the foamed resin molded product 90 is molded by the main body portion molded portion 80c, and the rib portion 95 of the foamed resin molded product 90 is molded by the rib portion molded portion 80b.

  Also in the foamed resin molded product 90, the main body 91 is formed by a non-foamed skin layer 92 whose surface is a surface layer, and foaming of the foamable resin 31 is promoted inside the skin layer 92. The foam layer 93 is formed, and the rib portion 95 is formed in a non-foamed state. The main body 91 of the foamed resin molded product 90 has a vertical wall 94 formed at the peripheral edge thereof, and the vertical wall 94 is formed in a non-foamed state.

  When the foamed resin molded product 90 having the main body portion 91 and the rib portion 95 is formed in this way and then taken out, the movable mold 61 is moved in the mold opening direction, and the mold 80 is moved to the mold. In the state where the rib portion 95 is held in the rib portion molding portion 80b, the rib portion 95 and the main body portion 91 are separated in the standing direction of the rib portion 95, so that the main body portion 91 continuous with the rib portion 95 is removed. The skin layer 92 is peeled off to expose the foam layer 93.

  FIG. 9 is a cross-sectional explanatory diagram for explaining a method of separating the main body portion and the rib portion of the foamed resin molded product in the mold shown in FIG. 7, and FIG. 9 (a) shows the mold opened. FIG. 9 (b) shows a state in which the pin portion protrudes from the movable body portion, and FIG. 9 (c) shows a state in which the fixed die is moved relative to the fixed die mounting plate. Is shown.

  As shown in FIG. 9A, when the foamed resin molded product 90 is molded and taken out, the movable part 61 is moved in the mold opening direction (direction indicated by the arrow X3) with the main body part 22 and the pin part 24 integrated. Then, the mold 80 is opened, and the main body 91 of the foamed resin molded product 90 is moved together with the movable die 61 in a state where the rib portion 95 is held by the rib portion molding portion 80b. The main body portion 91 includes a vertical wall portion 94 at the periphery thereof, and is formed to be held by the movable die 61 when the movable die 61 is moved.

  When the main body portion 91 of the foamed resin molded product 90 is moved together with the movable die 61, the rib portion 95 is formed in an undercut shape in the standing direction of the rib portion 95 by the rib portion connecting portion 97. The skin layer 92 of the main body 91 that continues to the rib portion 95 is peeled from the main body 91 together with the rib 95 while being held at 80b, and an opening 92a is formed in the skin layer 92 of the main body 91 to form a foam layer. 93 is exposed.

  When the mold 80 is opened, next, as shown in FIG. 9B, the pin 24 is closed with respect to the main body 22 of the movable mold 61 (the direction indicated by the arrow X4). The main body portion 91 of the foamed resin molded product 90 is moved in the opening / closing direction of the mold 80 from the cavity molding surface 22a of the main body portion 22 constituting the main body portion molding portion 80c. Thus, the main body 91 of the foamed resin molded product 90 falls from the mold 80, and the foamed resin molded product 90 is taken out. In this way, using the mold 80, it is possible to produce a foamed resin molded product 90 in which a part of the skin layer 92 is peeled and the foamed layer 93 is exposed.

  After the foamed resin molded product 90 is manufactured, as shown in FIG. 9C, the fixed die 81 is moved to the movable die 61 side (in the direction indicated by the arrow X5), and then held by the rib portion molding portion 80b. The rib 95 is dropped from the mold 80 and removed by blowing air from an air supply device (not shown) to the rib 95 formed.

  As described above, even when the mold according to the third embodiment of the present invention is used, the mold 80 includes the main body molding portion 80c for molding the main body 91 of the foamed resin molded product 90, and the main body. The rib portion molding portion 80b for molding the rib portion 95 standing on the surface of 91 is formed, and the rib portion molding portion 80b is formed in an undercut shape with respect to the standing direction of the rib portion 95. The rib 80 is formed to mold the rib portion 95. The mold 80 is formed when the foamed resin molded product 90 is taken out after the foamed resin molded product 90 having the main body portion 91 and the rib portion 95 is molded. The rib portion 95 and the main body portion 91 are separated in the standing direction of the rib portion 95 while the rib portion 95 is held, whereby the skin layer 92 of the main body portion 91 continuous with the rib portion 95 is peeled off to separate the main body portion. 91 so that the foam layer 93 is exposed. It is.

  As a result, the mold 80 having a relatively simple configuration can be used to peel off a part of the skin layer 92 of the foamed resin molded product 90 to expose the foamed layer 93, thereby reducing the strength of the foamed resin molded product 90. A foamed resin molded product 90 in which a part of the skin layer 92 is peeled and the foamed layer 93 is exposed can be molded while suppressing the above.

  The present invention is not limited to the illustrated embodiments, and it goes without saying that various improvements and design changes can be made without departing from the gist of the present invention.

  As described above, according to the present invention, a foamed resin molded product capable of molding a foamed resin molded product in which a foamed layer is exposed by peeling a part of the skin layer while suppressing a decrease in strength of the foamed resin molded product. Since it becomes possible to provide a mold structure for molding an article, it may be suitably used in the technical field of resin molding.

10, 50, 80, 110 Mold 10a, 50a, 80a, 110a Cavity 10b, 50b, 80b Rib part molding part 10c, 50c, 80c Body part molding part 31 Expandable resin 40, 70, 90, 100 Foamed resin molded product 41, 71, 91, 101 Body portion 42, 72, 92, 102 Skin layer 43, 73, 93, 103 Foam layer 45, 75, 95, 105 Rib portion

Claims (2)

A mold having a cavity for molding a foamed resin molded product and capable of expanding the volume of the cavity, and expanding the volume of the cavity after filling the cavity with a molten foamable resin. To form a foamed resin molded article having a skin layer as a surface layer and a foam layer provided on the inside of the skin layer, and then peeling off a part of the skin layer to expose the foam layer. A mold structure for molding a foamed resin molded product,
The mold has a main body part molding part for molding the main body part of the foamed resin molded product, and a rib part molding part for molding a rib part standing on the surface of the main body part, The rib part molding part is formed so as to mold the rib part formed in an undercut shape with respect to the standing direction of the rib part,
The mold has the rib portion in a state where the rib portion is held in the rib portion molding portion when the foamed resin molded product is taken out after the foam resin molding product having the main body portion and the rib portion is molded. By separating the rib portion and the main body portion in the standing direction, the skin layer of the main body portion continuous to the rib portion is peeled off to expose the foam layer of the main body portion ,
The mold includes a main body part that forms the cavity and a core part that is movably inserted into an opening provided in the main body part, and the rib part molding part is provided in the core part. The rib part is formed by a groove part and an opening part of the main body part, and the core part is moved by moving the core part after separating the rib part and the main body part of the foamed resin molded product. It is configured to expose the molding surface of the rib part molded by the opening,
A mold structure for molding a foamed resin molded product. The mold includes a projecting member for projecting the main body portion of the foamed resin molded product from the main body portion molding portion, and the rib portion is held in the rib portion molding portion when the foamed resin molded product is taken out. The projecting member is configured to project the body part from the body part molding part to separate the rib part and the body part,
The mold structure for molding a foamed resin molded product according to claim 1.

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