JP5285473B2 - Resin molded product molding method and resin molded product molding apparatus - Google Patents

Description

  The present invention relates to a method for molding a resin molded product and a molding apparatus for a resin molded product.

  As interior parts used in automobiles and homes, molded members with a skin having a three-layer structure of skin layer-foam layer-core material layer are frequently used. For the skin molding, an in-mold coating technique is used in which coating is performed in the mold. There are various types of in-mold coating techniques. For example, a paint is applied in a mold and a coating film is formed in advance (so-called mold coating). There is known a reaction injection (RIM) molding method for injecting a resin material provided with, and molding a resin molded product integrated with a coating film in a mold.

  In the above molding method, in order to prevent the resin material injected into the cavity from sticking to the molding surface, a release agent is applied to the molding surface prior to the injection of the resin. However, sticking of the resin material having excellent adhesiveness cannot be prevented by the release agent, and the resin molded product may be molded in a state of being stuck to the molding surface. In this case, the resin molded product may be stretched or cut due to mold opening or mold release.

  In order to prevent elongation and breakage of the resin molded product as described above, for example, a method of embedding an ejector device in the mold and releasing the gas between the molding surface and the resin molded product is used. (See Patent Document 1). The ejector device opens and closes a gas jet port provided on the molding surface with a valve body, and jets gas to the resin molded product. When the above-described ejector device is applied to a molding method in which molten resin material is injected into the cavity and molded, the gas jet port is blocked by the valve body, and the inflow of the resin material into the gas jet port is prevented. .

Japanese Patent No. 3949412

  However, in the RIM molding method described above, the resin material having fluidity cannot be blocked only by the valve body, and the resin material is formed from a slight gap formed between the valve body and the gas ejection port. There is a risk of causing leakage.

  When the resin material leaks into the gas ejection port, the resin material adheres inside the gas ejection port and clogs the resin material. When the clogging of the resin material occurs, it becomes difficult to normally and smoothly perform the opening and closing operation of the gas ejection port by the valve body. As a result, the ejection of gas during the mold release operation is hindered, the resin molded product is stretched or cut, and the appearance quality of the resin molded product is deteriorated.

  Therefore, the object of the present invention is to prevent the resin material from extending or breaking during the mold release operation by preventing the resin material from leaking into the gas outlet of the gas ejector provided in the mold. Another object of the present invention is to provide a method for molding a resin molded product and a molding apparatus for the resin molded product that can prevent the deterioration of the appearance quality of the resin molded product.

  The present invention is a method for molding a resin molded product for molding a resin material injected into a cavity, wherein a first molding surface for forming a cavity is formed, and the molded resin molded product is separated after clamping. A first mold having a gas ejection port for ejecting a mold release gas for molding on the first molding surface, a first mold that can be opened and closed relative to the first mold, and a first mold clamp The second mold on which the second molding surface forming a cavity is formed between the second molding surface and the second molding surface, and the paint for forming the coating film forming the surface layer is applied to the second molding surface. In addition, the method includes a step of applying the coating material to the first molding surface so as to form a seal portion that covers the gas ejection port. After the coating step, the first mold and the second mold are clamped, and a molten resin material is injected into the cavity to form a resin molded product integrated with the coating film forming the surface layer. doing. Furthermore, it has the process of releasing a resin molding product from a 1st type | mold while peeling off a seal part by ejecting the gas for mold release from a gas jet nozzle.

  Further, the present invention is a molding apparatus for a resin molded product for molding a resin material injected into a cavity, and a first molding for forming a cavity having an inner shape that matches the outer shape of the resin molded product. A first mold having a surface formed thereon; A second mold having a second molding surface provided so as to be openable and closable relative to the first mold and forming a cavity with the first molding surface by clamping; A gas ejector provided on the first molding surface with a gas ejection port for ejecting a release gas for releasing the resin molded product molded inside from the first mold. Further, a coating gun for applying a coating film forming a surface layer to the second molding surface and applying the coating material to the first molding surface so as to form a seal portion covering the gas ejection port, and a cavity Injection means for injecting molten resin material. Then, the sealing part is peeled off by ejecting a release gas from the gas ejection port, and a resin molded product formed by integrating the resin material injected into the cavity and the coating film forming the surface layer is formed into the first mold. Release from the mold.

  A seal portion is formed by applying a paint so as to cover the gas ejection port of the gas ejector, thereby preventing the resin material from leaking into the gas ejection port. For this reason, it is possible to prevent clogging of the resin material in the gas ejection port, and it is possible to perform the mold release operation without inhibiting the gas ejection. As a result, it is possible to prevent the resin molded product from being stretched or cut during the mold release operation, and to prevent the appearance quality of the resin molded product from being deteriorated.

It is a flowchart which shows the process of the molding method of the resin molded product which concerns on embodiment. It is sectional drawing which simplifies and shows the shaping | molding apparatus of a resin molded product. It is a figure which expands and shows a gas jet nozzle. It is sectional drawing for demonstrating the molding method of the resin molded product which concerns on embodiment. It is sectional drawing for demonstrating the molding method of the resin molded product which concerns on embodiment. It is sectional drawing for demonstrating the molding method of the resin molded product which concerns on embodiment. It is sectional drawing for demonstrating the molding method of the resin molded product which concerns on embodiment. FIG. 8A is a view showing a state in which the resin material has leaked between the valve member and the gas jet port in a proportional manner in which the resin material is prevented from flowing into the gas jet port only by the valve member. FIG. 8B is a diagram showing a state in which the leaked resin material is fixed and hinders the opening and closing operation of the gas ejection port by the valve member. 9 (A) and 9 (B) are diagrams showing a state in which the resin molded product is stretched or cut in a comparison with a molding method in which mold opening is performed without using a gas ejector, and FIG. FIG. 3 is a diagram showing a proportionality for preventing the resin molded product from being stretched or cut by forming a thick portion in the cavity. It is sectional drawing for demonstrating the resin molding apparatus and the resin molding method using the shaping | molding die concerning other embodiment. It is sectional drawing for demonstrating the resin molding apparatus and the resin molding method using the shaping | molding die concerning other embodiment.

  Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings. In the description of the drawings, the same elements are denoted by the same reference numerals, and redundant description is omitted. In addition, the dimensional ratios in the drawings are exaggerated for convenience of explanation, and may be different from the actual ratios.

  FIG. 2 shows a reaction injection (RIM) molding apparatus according to this embodiment. In the present embodiment, the molding method for resin molded products and the molding apparatus for resin molded products according to the present invention are applied to the RIM molding method and the RIM molding device. Examples of the resin molded product 530 molded by the RIM molding apparatus include a skin used for an interior door trim of an automobile part having a three-layer structure of a skin layer, a foam layer, and a core material layer. The paint 361 and the resin material 500 are made of a urethane-based material generally used for polyurethane RIM molding.

  Referring to FIGS. 2 to 7, the resin molded product molding apparatus 300 is roughly described in the core mold 310 (corresponding to the first mold) in which the first molding surface 311 is formed, and the core mold 310. On the other hand, a second molding surface 321 is provided that can be opened and closed relatively, and forms a cavity 340 having an inner shape that matches the outer shape of the resin molded product 530 between the first molding surface 311 and clamping. A mold 320 (corresponding to the second mold) formed with a gas outlet 351 for ejecting a release gas 359 for releasing the resin molded product 530 molded in the cavity 340 from the core mold 310. A gas ejector 350 provided on the first molding surface 311 and a coating material 361 for forming a surface coating layer 362 (hereinafter referred to as coating layer) are applied to the second molding surface 321 and the coating material 361 is jetted out. 351 and the coating gun 360 to be applied to the first shaping surface 311 to form a seal portion 363 which covers the has an injection unit 370 for injecting the resin material 510 which is melted in the cavity 340, the. Then, by ejecting a release gas 359 from the gas outlet 351, the seal portion 363 is peeled off, and a resin molded product 530 formed by integrating the resin material 500 injected into the cavity 340 and the coating film 362 is obtained. It is released from the core mold 310.

  The first molding surface 311 of the core mold 310 has a convex shape that protrudes with respect to the mold 320, and the second molding surface 321 of the mold 320 generally has The core mold 310 has a recessed shape that is recessed. The released resin molded product 530 is left in the mold 320 (see FIG. 7A). The gas ejector 350 includes a valve member 354 that is provided so as to be movable in a direction protruding from the first molding surface 311 and presses the seal portion 363 by movement in the protruding direction (see FIG. 3). Hereinafter, this embodiment will be described in detail.

  With reference to FIG. 2, a molding apparatus 300 for a resin molded product includes a molding die 330 including a core mold 310 and a cavity mold 320, and a control unit 390 that controls the operation of each part of the apparatus. .

  The core mold 310 is provided so as to be movable toward and away from the mold mold 320. The mold mold 330 is clamped by moving the core mold 310 closer to the mold mold 320 (moving downward in the figure, indicated by an arrow a) (see FIG. 6A). The mold 330 is opened by moving the core mold 310 away from the cavity mold 320 (upward movement in the figure, indicated by an arrow b) (see FIG. 7A). Mold clamping, mold opening, and other operations of the molding die 330 are performed according to a control signal s1 transmitted by the control unit 390 described later.

  On the first molding surface 311 of the core mold 310, an uneven portion is partially formed in accordance with the shape of the resin molded product 530. On the other hand, the second molding surface 321 of the mold 320 is partially formed with an irregular portion having a shape that matches the irregular portion provided on the first molding surface 311. A cavity 340 that matches the outer shape of the resin molded product 530 is formed between the first molding surface 311 and the second molding surface 321 by clamping.

  In view of the design appearance of the resin molded product, an inverse shape may be formed on the molding surface of the mold. The resin molded product cannot be removed from the molding surface on which the inverse shape is formed only by opening the mold. For this reason, in general, an undercut processing structure including a slide mold and a slide pin is provided in the mold and the resin molded product is taken out.

  However, when an undercut processing structure is provided in the mold, the apparatus configuration of the molding apparatus is complicated. For this reason, when the molded product has flexibility like the resin molded product 530, when the mold is opened, the resin molded product is left on the mold and the inverse shaped portion is elastically deformed. The method of taking out may be adopted.

  In the molding method according to the embodiment, the resin molded product 530 is left on the cavity mold 320 by the release gas 359 ejected from the core mold 310 (see FIG. 7A). When applied to a molding method using a mold having an inverse shape formed on the molding surface, it is possible to adopt a method in which the inverse shaped portion is elastically deformed to take out a resin molded product from the molding surface.

  The control unit 390 transmits a control signal and causes each unit of the device to execute a preset operation. The control unit 390 controls, for example, the timing at which the mold release gas 359 is sprayed, the ejection amount of the mold release gas 359, the mold clamping and mold opening timing of the mold 330.

  The gas ejector 350 includes a release gas supply unit 352 for supplying a release gas 359 stored in a chamber (not shown), a gas supply path 353a provided in the core mold 310, and a first molding. A gas outlet 351 disposed on the surface 311 and a valve member 354 provided in the gas outlet 351 are provided.

  The gas ejector 350 sends the release gas 359 into the gas supply path 353a in accordance with the control signal s2 transmitted from the control unit 390. The release gas 359 is ejected from the gas ejection port 351 through the gas supply path 353a.

  Referring to FIGS. 3A and 3B, the valve member 354 is disposed on the side on which the release gas 359 is supplied and on the first molding surface 311 side. And a lid portion 356 for opening and closing the gas outlet 351, a shaft portion 357 for connecting the locking portion 355 and the lid portion 356, and an elastic member 358 capable of compressing and deforming to support the locking portion 355. ing. Although the spring member is used for the elastic member 358, it is not limited to this, It can change suitably.

  The valve member 354 moves from the initial position p to the first molding surface 311 by ejecting the release gas 359 and opens the gas ejection port 351 (FIG. 3B). See).

  The locking portion 355 moves in a direction protruding from the first molding surface 311 while receiving the wind pressure of the release gas 359 and compressing the elastic member 358. As the locking portion 355 moves, the shaft portion 357 and the lid portion 356 also move in a direction protruding to the first molding surface 311, and the entire valve member 354 moves in a direction protruding to the first molding surface 311. .

  By moving the lid portion 356, the gas ejection port 351 is opened. While the release gas 359 is being ejected, the locking portion 355 continues to receive the wind pressure of the release gas 359. Thereby, since the elastic member 358 is maintained in a compressed state, the gas ejection port 351 can be maintained in an open state.

  The lid part 356 moves so as to press the seal part 363, and forms a gap g between the gas ejection port 351 and the seal part 363. When forming the gap part g, the seal part 363 is pressed to assist the release of the resin molded product 530.

  During the mold release operation, the mold release gas 359 is ejected so as to flow into the gap g. A release gas 359 is sprayed onto the resin molded product 530 through the seal portion 363. By spraying the release gas 359, the seal portion 363 is peeled off and the resin molded product 530 is released from the core mold 310 (see FIG. 7A).

  As described above, the valve member 354 moves in a direction protruding from the first molding surface 311, and forms a gap portion g between the first molding surface 311 and the seal portion 363. By blowing the release gas 359 so as to flow into the gap portion g, the wind pressure of the release gas 359 applied to the seal portion 363 and the resin molded product 530 can be increased. For this reason, the resin molded product 530 can be released from the core mold 310 more smoothly.

  When the ejection of the release gas 359 is stopped, the elastic member 358 expands, and the entire valve member 354 moves toward the initial position p as the locking portion 355 moves. By returning the valve member 354 to the initial position p, the gas ejection port 351 is closed.

  The type of release gas 359 is not particularly limited, but it is desirable to use air or the like in order to reduce costs. For example, a release agent 359 can be ejected by mixing a release agent. When the resin material 500 enters the gas ejection port 351 due to insufficient application of the paint 361 forming the seal portion 363 or insufficient thickness of the seal portion 363, the resin material 500 can be easily removed. It becomes possible. It is desirable that the release agent is mixed with the release gas 359 periodically to be ejected for maintenance of the gas outlet 351.

  As the coating gun 360, a general coating film spray gun can be used (see FIG. 5A). The coating gun 361 applies the paint 361 to the first molding surface 311 and the second molding surface 321. On the second molding surface 321, a paint 361 is applied to the entire molding surface 321 to form a coating film 362 for constituting the design appearance of the product. The first molding surface 311 is coated with a paint 361 so as to cover the gas ejection port 351 to form a seal portion 363. The seal portion 363 is only required to be formed at least to the extent that the resin material 500 is prevented from flowing into the gas ejection port 351, and need not be formed on the entire first molding surface 311.

  Further, when the product shape is complicated, the paint is applied to a part other than the seal portion 363 of the gas outlet 351, for example, a part having a draft angle of about 1 to 5 ° (a draft angle θ, see FIG. 9A). By applying 361, it is possible to increase the releasability between the part to which the paint 361 is applied and the molding surface 311 than the releasability between the resin material 500 having high adhesion and the molding surface 311. . Therefore, in the case where mold release assistance is performed, there is no problem even if the coating material 361 is applied to the molding surface 311 at a portion other than the portion where the seal portion 363 is formed at the gas outlet 351.

  The RIM molding used in the main molding generally has high adhesiveness of the material and has fluidity close to liquid and water, so that a solid (pellet) that is a general injection molding material is melted while being melted. Compared to injection molding that flows inward, the fluidity is much better. Since the fluidity of the RIM material is very good, a phenomenon occurs in which the material that reacts when there is a small gap in the mold flows into the gap and adheres due to good adhesion and fluidity. Therefore, by forming the single-layer coating film layer 363 so as to cover the gap, even a highly fluid material penetrates the coating film 363 and leaks to the first molding surface 311 side. And can be molded.

  In addition, it is necessary that the first molding surface 311 to which the coating material is applied has at least a film state, and in a state where a fine through hole such as a porous shape is opened too thinly, It is difficult to exert the effect of preventing the flow into the gap. For this reason, although there are differences depending on the paint used, it is desirable to set the film thickness so that it does not become porous.

  In order to sufficiently exhibit the above effects, for example, it is desirable to form the film with a film thickness of about the same as 5 to 10 μm or larger. Further, by increasing the film thickness, it is possible to increase the strength of the film itself and to more reliably prevent the resin material 510 from entering. In addition, the dimension of a film thickness is not limited to what was illustrated, It can change suitably.

  When applying the paint 361, a masking jig 395 is disposed on the mating surface 335 of the mold 320 (see FIG. 5A). This is to prevent the paint 361 from being applied to an unintended part by the masking jig 395. For the masking jig 395, for example, a metal member having an appropriate shape can be used.

  The coating film 362 and the seal portion 363 can be formed with the same paint 361, and the cost required for the molding operation can be reduced. Since the same paint 361 can be used, the paint spray gun for forming the coating film 362 and the paint spray gun for forming the seal portion 363 can be shared, and the equipment cost of the apparatus can be reduced. Can do.

  Referring to FIG. 2 again, the injection means 370 includes a resin material supply unit 371 that supplies the resin material 510 stored in a chamber (not shown), and a mixing head that injects the molten resin material 510 into the cavity 340. 372. The injection unit 370 sends the molten resin material 510 from the resin material supply unit 371 to the mixing head 372 in accordance with the control signal s3 transmitted from the control unit 390. The mixing head 372 injects the molten resin material 510 into the cavity 340 through a gate provided between the core mold 310 and the cavity mold 320 (see FIG. 6B).

  In order to facilitate the removal of the resin molded product 530 from the mold 330, the resin molded product molding apparatus 300 applies a release agent 381 to the first molding surface 311 and the second molding surface 321 prior to the application of the paint 361. A release agent applying means 380 for applying is provided (see FIG. 4A, the release agent 381 after application is omitted in the figure). As the release agent coating means 380, a general release agent spray gun can be used. As the release agent 381, for example, wax, metal soap, silicone release agent, or the like used as a release agent of a molding apparatus for resin molding can be used.

  Next, a method for molding a resin molded product will be described.

  Referring to FIG. 1, the molding method of the resin molded product 530 can be summarized as follows: a step of applying a release agent 381 (S11), a step of placing a masking jig 395 (S12), a molding surface 311; The step of applying the paint 361 to the 321 (S13), the step of removing the masking jig 395 (S14), the step of clamping the mold (S15), the step of injecting the resin material 510 (S16), and opening the mold At the same time, the method includes a step (S17) of releasing the resin molded product 530 by ejecting a release gas 359 and a step (S18) of taking out the resin molded product 530. In the step of releasing the resin molded product 530 (S17), the release gas 359 is ejected while the core mold 310 and the cavity mold 320 are opened. Hereinafter, each process is explained in full detail.

  With reference to FIG. 4 (A), the process of apply | coating the mold release agent 381 is performed (S11). With the core mold 310 and the mold mold 320 opened, a release agent 381 is applied to the first molding surface 311 and the second molding surface 321. The release agent 381 is applied by a release agent spray gun 380.

  With reference to FIG. 4 (B), the process of arrange | positioning the masking jig | tool 395 is performed (S12). The masking jig 395 is disposed on the mating surface 335 of the mold 320 so as to regulate the range where the paint 361 is applied.

  With reference to FIG. 5 (A), the process of apply | coating the coating material 361 to the molding surfaces 311 and 321 is performed (S13). The paint 361 is applied to the second molding surface 321 so that the coating film 362 is formed on the entire molding surface 321. A coating 361 is applied to the first molding surface 311 so as to cover the gas ejection port 351 provided on the first molding surface 311 to form a seal portion 363. As the paint 361, the same paint 361 is used, and the coating operation is performed by the common coating film spray gun 360.

  Referring to FIG. 5B, a step of removing masking jig 395 is performed (S14). The masking jig 395 disposed on the mating surface 335 of the mold 320 is removed.

  Referring to FIG. 6A, a mold clamping step is performed (S15). After the step of applying the paint 361, the core mold 310 is moved closer to the mold mold 320, and the mold 330 is clamped. A cavity 340 having a shape that matches the outer shape of the resin molded product 530 is formed between the first molding surface 311 of the core mold 310 and the second molding surface 321 of the mold mold 320.

  Referring to FIG. 6B, a step of injecting resin material 510 is performed (S16). The resin material 510 melted by the injection means 370 is injected into the cavity 340. The molten resin material 510 has fluidity and adhesiveness for forming the resin molded product 530 by being integrated with the coating film 362. The seal portion 363 formed prior to the injection of the molten resin material 510 prevents the resin material 510 from flowing into the gas ejection port 351.

  Here, in FIG. 8A, a resin between the valve member 640 and the gas jet port 610 is shown in a proportional manner to prevent the molten resin material 510 from flowing into the gas jet port 610 only by the valve member 640. FIG. 8B shows a state in which the material 510 has leaked, and FIG. 8B shows a state in which the leaked resin material 510 is fixed and prevents the valve member 640 from opening and closing the gas ejection port 351.

  The valve member 640 is configured to open and close the gas outlet 610 by moving forward and backward toward the molding surface 620. By closing the gas ejection port 610, the inflow of the resin material 510 injected into the cavity is prevented. In order to enable the valve member 640 to move forward and backward toward the molding surface 620, it is necessary to provide a gap between the valve member 640 and the gas ejection port 610. The resin material 510 having fluidity leaks from the gap into the gas ejection port 610 (see FIG. 8A).

  The resin material 510 that has leaked into the gas ejection port 610 is fixed between the valve member 640 and the gas ejection port 610 due to its adhesiveness. The fixed resin material 520 hinders the opening / closing operation of the gas ejection port 610 by the valve member 640. For this reason, the opening and closing operation of the gas outlet 610 by the valve member 640 cannot be performed normally and smoothly during the release operation, and it becomes difficult to eject a sufficient amount of release gas required for release ( (See FIG. 8B). As a result, the resin molded product is released in a state of being attached to the molding surface, and the resin molded product is elongated or cut as described later (see FIG. 9B).

  On the other hand, in the present embodiment, the seal portion 363 is formed by the paint 361 applied so as to cover the gas outlet 351 prior to the injection of the molten resin material 510. The seal portion 363 blocks leakage of the resin material 510 into the gas ejection port 351. For this reason, it is possible to prevent the clogging 520 of the resin material from occurring in the gas outlet 351, and the resin molded product 530 can be released without inhibiting the ejection of the release gas 359. As a result, it is possible to prevent the resin molded product 530 from being stretched or cut during the mold release operation, and to prevent the appearance quality of the resin molded product 530 from being deteriorated.

  Referring to FIG. 7A, a step of opening the mold 330 and ejecting the mold release gas 359 to release the resin molded product 530 is performed (S17). In a state where the melted resin material 510 is cured and the coating film 362 and the resin material 500 are integrally molded, the core mold 310 is moved away from the cavity mold 320 to open the mold 330. While opening the molding die 330, the gas ejector 350 causes the release gas 359 to be ejected.

  The gas ejector 350 sends the release gas 359 from the release gas supply unit 352 to the gas supply path 353a. The release gas 359 moves the valve member 354 provided in the gas ejection port 351 in a direction protruding from the first molding surface 311. The valve member 354 presses the seal portion 363 by movement in the protruding direction, and forms a gap portion g between the seal portion 363 and the first molding surface 311 (see also FIG. 3B). When forming the gap part g, the valve member 354 presses the seal part 363 and assists the mold release of the resin molded product 530.

  The release gas 359 is sprayed so as to flow into the gap g. By blowing the release gas 359 so as to flow into the gap portion g, the wind pressure of the release gas 359 applied to the seal portion 363 and the resin molded product 530 is increased.

  By releasing the release gas 359, the seal portion 363 is peeled off from the first molding surface 311, and the release gas 359 is jetted so as to flow between the first molding surface 311 and the resin molded product 530. Thus, the resin molded product 530 is released from the core mold 310.

  The resin molded product 530 released from the core mold 310 is left on the cavity mold 320.

  9 (A) and 9 (B), the resin molded product 530 is stretched or cut in comparison with the molding method in which the mold is opened without using the gas ejector 350 or when the mechanism does not function. FIG. 9C shows a state in which the thick portion 730 is formed in the cavity 340 to thereby prevent the resin molded product 530 from being stretched or cut.

  Protrusions and recesses are formed on the molding surfaces 711 and 721 so as to match the outer shape of the resin molded product 530. In the cavity, the draft angle (drawing angle θ) at the time of mold opening is smaller in the part where the vertical wall part of the convex part and the vertical wall part of the concave part face each other than in other parts. In such a part, the resin molded product 530 is more easily attached (see FIG. 9A).

  When the mold opening is performed in a state where the resin molded product 530 is attached to the first molding surface 711, the resin molded product 530 is stretched as illustrated. Moreover, there is a possibility that the resin molded product 530 may be cut when the mold is opened in a state where the elongation occurs (see FIG. 9B).

  When the thick part 730 is formed and the draft is increased, sticking of the resin molded product 530 can be suppressed. However, since the thick-walled portion 730 has a larger cross-sectional area than other portions in the cavity 340, a void 740 is easily generated (see FIG. 9C). When the void 740 is generated, the feel of the resin molded product 530 becomes hard, so that the product quality of the resin molded product 530 is deteriorated. Moreover, in order to form the thick part 740, it is necessary to inject | pour the resin material 500 extra. For this reason, the cost which resin molding requires increases.

  On the other hand, in the present embodiment, the release gas 359 ejected from the gas ejector 350 provided in the core mold 310 is poured between the first molding surface 311 and the resin molded product 530. The resin molded product 530 is released from the first molding surface 311 side. Therefore, even when the mold release agent 381 is applied to the molding surfaces 311 and 321, even when the resin molded product 530 is stuck to the molding surfaces 311 and 321, the resin molding is performed when the mold is opened. It is possible to prevent the product 530 from being stretched or cut.

  Further, since the mold release gas 359 is ejected while the mold is opened, it is possible to prevent the part released from the first molding surface 311 in the resin molded product 530 from being attached to the first molding surface 311 again. It is possible to more reliably prevent the molded product 530 from being stretched or cut. Since the resin molded product 530 can be released while the mold is opened, the working efficiency of the molding operation can be improved.

  Referring to FIG. 7A again, the seal portion 363 peeled off from the core mold 310 remains on the surface opposite to the surface on which the coating film 362 is formed. Since the surface on the side opposite to the surface on which the coating film 362 is formed does not constitute the appearance of the design of the product, there is no possibility that the appearance quality is deteriorated by the remaining seal portion 363. In addition, the seal portion 363 can be removed as appropriate.

  Referring to FIG. 7B, a step of taking out resin molded product 530 is performed (S18). Since the resin molded product 530 is prevented from being stretched or cut during the mold release operation, the molded resin molded product 530 can be obtained without deteriorating the appearance quality.

  Since the released resin molded product 530 is left on the mold mold 320, the inverse shaped portion is elastically deformed when applied to a molding method using the mold mold 320 having a molding surface formed with an inverse shape. The resin molded product 530 can be taken out.

  As described above, according to the present embodiment, the sealing portion 363 is formed by the coating material 361 applied so as to cover the gas ejection port 351 prior to the injection of the molten resin material 510, and the gas is injected into the gas ejection port 351. The leakage of the resin material 510 is blocked. For this reason, it is possible to prevent the clogging 520 of the resin material from occurring in the gas outlet 351, and the resin molded product 530 can be released without inhibiting the ejection of the release gas 359. As a result, it is possible to prevent the resin molded product 530 from being stretched or cut during the mold release operation, and to prevent the appearance quality of the resin molded product 530 from being deteriorated.

  Since the released resin molded product 530 is left on the mold mold 320, the inverse shaped portion is elastically deformed when applied to a molding method using the mold mold 320 having a molding surface formed with an inverse shape. The resin molded product 530 can be taken out.

  Since the mold release gas 359 is ejected while the mold is opened, it is possible to prevent the part released from the first molding surface 311 in the resin molded product 530 from sticking to the first molding surface 311 again. It is possible to more reliably prevent the 530 from being stretched or cut. Since the resin molded product 530 can be released while the mold is opened, the working efficiency of the molding operation can be improved.

  The valve member 354 moves in a direction protruding from the first molding surface 311, and forms a gap portion g between the first molding surface 311 and the seal portion 363. By blowing the release gas 359 so as to flow into the gap portion g, the wind pressure of the release gas 359 applied to the seal portion 363 and the resin molded product 530 can be increased. For this reason, the resin molded product 530 can be released from the core mold 310 more smoothly.

(Other embodiments)
FIGS. 10 and 11 are cross-sectional views for explaining a method for molding a resin molded product using a molding die 330 according to another embodiment and a molding apparatus for the resin molded product. Members that are common to the members shown in FIGS.

  Referring to FIGS. 10 and 11, a mold 330 in another embodiment includes a movable mold 410 disposed on a mating surface 335 where the clamped core mold 310 and the mold mold 320 are abutted, and a movable mold. And connecting means 420 for connecting 410 to the core mold 310.

  The movable mold 410 is provided so as to be movable in the mold opening / closing direction of the molding mold 330 and blocks communication between the cavity 340 and the outside of the cavity 340. The movable mold 410 communicates between the cavity 340 and the outside of the cavity 340 in a state in which the release gas 359 is being ejected while moving in the mold opening direction in conjunction with the mold opening of the core mold 310 at the initial stage of mold opening. Cut off.

  The movable mold 410 communicates between the cavity 340 and the outside of the cavity 340 in a state in which the release gas 359 is being ejected while moving in the mold opening direction in conjunction with the mold opening of the core mold 310 at the initial stage of mold opening. Cut off. As a result, when air flows into the cavity 340 immediately after the release gas 359 is ejected, the release effect due to the ejection of the release gas 359 is not sufficiently exerted, and the resin molded product 530 is released. Prevents the mold from becoming difficult.

  In the movable mold 410, a gas supply path 353b formed so as to communicate with the gas supply path 353a in the core mold 310 is provided. By tightening the mold, the gas supply paths 353a and 353b of both are brought into communication.

  The connection means 420 has a connection hole 421 provided in the movable mold 410 and a connection pin 422 that moves in the connection hole 421 in the opening / closing direction of the molding die 330.

  One end of the connecting pin 422 is fixed to the core mold 310. An engaging portion 423 that moves the movable die 410 in conjunction with the mold opening of the molding die 330 by abutting against the inner wall of the coupling hole 421 is provided at the other end of the connecting pin 422. A fixed distance (stroke amount) w is provided between the connecting pin 422 and the abutting portion 425 in the connecting hole 421 to which the engaging portion 423 is abutted.

  As a method of fixing the connecting pin 422 and the core mold 310, welding or screwing can be appropriately selected.

  Next, with reference to FIG. 10 and FIG. 11, the molding method of the resin molded product of this embodiment is demonstrated.

  Referring to FIG. 10A, a resin molded product 530 in which the resin material 510 injected into the cavity 340 and the coating film 362 are integrated is molded.

  Referring to FIG. 10B, the core mold 310 is moved away from the mold mold 320, and the mold release gas 359 is ejected. By ejecting the release gas 359, the seal portion 363 is peeled off and the resin molded product 530 is released from the core mold 310.

  When the core mold 310 is moved in the mold opening direction to open the mold 330, the connecting pin 422 moves in the mold opening direction together with the core mold 310. Due to the movement of the connecting pin 422, the engaging portion 423 comes into contact with the abutting portion 425.

  Referring to FIG. 11A, when the core mold 310 is further moved in a state where the engaging portion 423 is abutted against the abutting portion 425, the movable die 410 is opened in conjunction with the movement of the core die 310. The cavity 340 and the outside of the cavity 340 communicate with each other.

  By providing a certain distance w between the engaging portion 423 and the abutting portion 425, a time difference is provided between the timing when the core die 310 starts moving and the timing when the movable die 410 starts moving. Is possible. Due to this time difference, it is possible to keep the cavity 340 and the outside of the cavity 340 not communicating with each other immediately after starting the ejection of the release gas 359 while performing mold opening.

  In the resin molded product molding apparatus 300 of this embodiment, the movable die 410 blocks communication between the cavity 340 and the outside of the cavity 340. By providing a time difference between the timing at which the movable mold 410 moves and the timing at which the core mold 310 moves, the mold 330 is opened and the cavity 340 immediately after the release gas 359 is jetted. The communication with the outside of the cavity 340 is blocked. For this reason, it is possible to sufficiently exert the mold release effect due to the ejection of the mold release gas 359 and to release the resin molded product 530 from the core mold 310 more reliably.

  With reference to FIG. 11 (B), the resin molded product 530 left in the mold 320 is taken out.

  As described above, even in the present embodiment, it is possible to prevent the clogging 520 of the resin material from occurring in the gas ejection port 351, and to release the resin molded product 530 without hindering the ejection of the release gas 359. Can do. As a result, it is possible to prevent the resin molded product 530 from being stretched or cut during the mold release operation, and to prevent the appearance quality of the resin molded product 530 from being deteriorated.

  Further, by providing a time difference between the timing at which the movable mold 410 moves and the timing at which the core mold 310 moves, the cavity immediately after the mold release gas 359 is jetted while the mold 330 is opened. The communication state between 340 and the outside of the cavity 340 can be blocked. For this reason, the mold release effect by the ejection of the mold release gas 359 can be sufficiently exerted, and the resin molded product 530 can be released from the core mold 310 more reliably.

  This embodiment can be modified as appropriate.

  For example, although the gas ejector 350 is provided in the core mold 310, the gas ejector 350 can be provided in the cavity mold 320. When the undercut shape is not formed on the core mold 310, the mold release gas 359 is ejected while moving the mold mold 320 away from the core mold 310, and the resin molded product 530 is ejected from the core mold 310. It is also possible to leave them.

  The number of the gas ejectors 350 to be provided and the place where the gas ejectors 350 are arranged are not particularly limited. It is possible to appropriately change within a range in which the mold release gas 359 is ejected from the gas outlets 351 provided on the molding surfaces 311 and 321 and the resin molded product 530 can be released.

  The mold release gas 359 is ejected together with the mold opening, but the ejection timing can be changed as appropriate. For example, after the resin material 500 is integrated with the coating film 362, the ejection of the release gas 359 can be started immediately before the mold opening is started.

  The paint 361 and the resin material 500 are not limited to urethane-based materials, and for example, materials made of other thermoplastic and thermosetting resins can be used.

  The movable mold 410 is connected to the core mold 310 and moved in the mold opening direction in conjunction with the mold opening. For example, in the case of an apparatus configuration in which the mold opening is performed by moving the mold 320, the mold It is also possible to connect to the mold 320 and move in conjunction with the mold opening.

  The stroke amount w can be changed as appropriate. By adjusting the stroke amount w, it is possible to adjust the time difference between the timing at which the mold opening is started and the timing at which the movable mold 410 moves in the mold opening direction.

  The molding method and molding apparatus for a resin molded product according to the present invention are not used only for reaction injection molding, but a coating is applied to a molding surface of a plurality of molds that are relatively openable and closable. The present invention can be widely applied to a molding method and a molding apparatus for the purpose of obtaining a resin molded product formed and integrated with the coating film and the resin material.

300 Molding device for resin molded products,
310 Core type (first type),
311 first molding surface,
320 Cavity type (second type),
321 second molding surface;
330 mold,
335 mating surface,
340 cavities,
350 gas ejector,
351 gas outlet,
352 release gas supply section,
353a, 353b gas supply path,
354 valve member,
355 locking part,
356 lid,
357 shaft,
358 elastic member,
359 release gas,
360 gun for application,
361 paint,
362 surface coating film,
363 seal part,
370 injection means,
371 Resin material supply unit,
372 mixing head,
380 release agent application means,
381 mold release agent,
390 control unit,
395 masking jig,
410 Movable type,
420 connecting means,
421 connecting hole,
422 connecting pin,
423 engaging portion,
425 butting part,
500 resin material,
510 molten resin material,
520 fixed resin material,
530 resin molded product,
g Gap,
p initial position,
θ draft angle,
w Stroke amount,
s1, s2, s3 Control signals.

Claims (6)

A first molding surface for forming a cavity is formed, and the first molding surface is provided with a gas ejection port for ejecting a mold release gas for releasing a resin molded product molded after clamping. A second molding surface that is provided so as to be openable and closable relative to the first mold and the first mold and that forms the cavity between the first mold surface and the first molding surface is formed by clamping. With the second mold open,
Applying a paint for forming a coating film forming a surface layer to the second molding surface and applying the paint to the first molding surface so as to form a seal portion that covers the gas ejection port;
After the applying step, the first mold and the second mold are clamped, and a molten resin material is injected into the cavity to mold a resin molded product integrated with the coating film forming the surface layer. Process,
A step of peeling off the seal portion by ejecting the release gas from the gas outlet and releasing the resin molded product from the first mold.   2. The method for molding a resin molded product according to claim 1, wherein in the step of releasing the resin molded product, the release gas is ejected while opening the first mold and the second mold.   The first molding surface has a convex shape protruding with respect to the second mold, and the second molding surface has a concave shape recessed with respect to the first mold. The method for molding a resin molded product according to claim 1 or 2, wherein the molded resin molded product is left in the first mold. A first mold on which a first molding surface for forming a cavity having an inner shape that matches the outer shape of the resin molded product is formed;
A second mold that is provided so as to be openable and closable relative to the first mold and in which a second molding surface is formed between the first molding surface and the first molding surface by clamping.
A gas ejector provided on the first molding surface with a gas ejection port for ejecting a release gas for releasing the resin molded product molded in the cavity from the first mold;
An application gun for applying a paint for forming a coating film forming a surface layer to the second molding surface and applying the paint to the first molding surface so as to form a seal portion covering the gas ejection port;
Injection means for injecting molten resin material into the cavity,
A resin molded product in which the sealing material is peeled off by ejecting the release gas from the gas ejection port, and the resin material injected into the cavity and the coating film forming the surface layer are integrally formed. A molding apparatus for a resin molded product, which is released from the first mold.   The molding of the resin molded product according to claim 4, wherein the gas ejector includes a valve member that is provided so as to be movable in a direction protruding from the first molding surface and presses the seal portion by movement in the protruding direction. apparatus. A movable mold disposed on a mating surface where the clamped first mold and the second mold face each other, and movable in a mold opening and closing direction that blocks communication between the cavity and the outside of the cavity; and the movable Coupling means for coupling a mold to the first mold or the second mold,
The movable mold blocks communication between the cavity and the outside of the cavity in a state in which the release gas is ejected while moving in the mold opening direction in conjunction with mold opening. Item 6. An apparatus for molding a resin molded product according to Item 5.

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