JP5190952B2 - Bonding structure of foamed resin molded products - Google Patents

Description

  The present invention provides a bonding structure between a foamed resin molded product molded by adopting a molding method in which the mold clearance of the molding die is varied between the injection filling process and the foam molding process of the foamed resin material, and the resin molded product on the other side. In particular, the present invention relates to a bonded structure of a foamed resin molded product that can eliminate a defect in lack of wall due to insufficient foaming at the time of molding the foamed resin molded product and can secure a stable bonding posture between the foamed resin molded product and the resin molded product.

  FIG. 15 is a front view showing a luggage side trim 1 mounted on the interior side of a side wall panel in a luggage room of the vehicle. The luggage side trim 1 is formed by joining and fixing an upper and lower divided body of a trim upper 2 and a trim lower 3. Configured. In this conventional example, the trim upper 2 employs a foamed resin molded product that is lightweight and excellent in impact resistance, and the trim lower 3 employs a synthetic resin injection molded product or a resin molded product formed of a mold press molded product. ing. As shown in FIG. 16, the trim upper 2 and the trim lower 3 partially overlap the lower edge of the trim upper 2 and the upper edge of the trim lower 3, and the trim upper 2 in the overlap portion has a joining flange. 4 is extended, and attachment holes 4a are opened at predetermined intervals along the width direction at predetermined locations of the joining flange 4. On the other hand, the trim lower 3 is welded after the welding boss 5 is erected toward the back side corresponding to the mounting hole 4a of the trim upper 2 and the welding boss 5 is inserted into the mounting hole 4a. By applying ultrasonic welding or the like to the tip of the boss 5, the trim upper 2 and the trim lower 3 are firmly joined and integrated. And the cross-shaped reinforcement rib 5a is integrated around the welding boss | hub 5, By abutting this reinforcement rib 5a on the attachment seat surface of the flange 4 for a joint of the trim upper 2, both joint attitude | positions are made. I try to keep it good.

  Next, the configuration of a molding die used for molding the trim upper 2 will be described with reference to FIG. As shown in FIG. 17, the molding die 6 is generally composed of a movable die 7 and a fixed die 8. The movable die 7 is fixed to the fixed die 8 by driving a drive cylinder 7a. On the other hand, the mold is opened and the mold is clamped. As a supply system for supplying the foamed resin material M into the cavity C defined between the movable mold 7 and the fixed mold 8, an injection machine 8a is connected to the fixed mold 8. The foamed resin material M supplied from the injection machine 8a is injected and filled into the cavity C through a hot runner 8b and a valve gate 8c provided in the stationary mold 8. Next, when the injection filling process of the foamed resin material M is completed, the movable mold 7 is moved backward by a minute stroke to widen the mold clearance, and then the foamed resin material M is foam-molded to obtain the product surface. The formation of the trim upper 2 having the two-layer structure of the skin layer 2a and the inside of the foam layer 2b is completed. In addition, as a conventional example of a manufacturing method of a foamed resin molded product that employs two processes of an injection filling process of the foamed resin material M and a foam molding process that ensures a large mold clearance, it is described in detail in Patent Document 1. Yes.

JP 2002-120252 A

  As described above, in the conventional molding method of the trim upper (foamed resin molded product) 2 in the luggage side trim 1, the precision is adjusted by adjusting the mold clearance between the movable mold 7 and the fixed mold 8. Good molding. That is, at the time of injection filling of the foamed resin material M, the mold clearance is reduced to supply the foamed resin material M into the cavity C in a state where foaming is suppressed, and at the time of the foaming reaction, the mold clearance is set to be large. The trim upper 2 can be accurately molded into the final product shape.

  However, on the end side of the product, for example, the end portion of the joining flange 4 of the trim upper 2 is a portion where the foamed resin material M finally reaches, and as shown in an enlarged view in FIG. In this respect, since the cooling surface of the mold comes into contact with the foamed resin material M, there is a problem that the skin layer 2a is formed quickly, resulting in a lack of foam due to insufficient foaming. Therefore, if the trim upper 2 and the trim lower 3 are joined and fixed in a state where the terminal side of the trim upper 2 is thin, the trim lower 3 and the trim lower 3 are moved in the direction of the arrow as shown in FIG. There is a problem in that a gap, a step, or the like occurs in the matching portion (indicated by a in FIG. 18), and the appearance appearance is remarkably deteriorated.

  The present invention has been made in view of such circumstances, and uses a molding die composed of a movable side mold and a fixed side mold that can be mutually opened and clamped, and injection filled with a foamed resin material. Foamed resin molding in the joint structure of a foamed resin molded product that joins a molded resin molded product molded by adopting a molding method that adjusts the mold clearance of the molding die in the process and foam molding process There is no lack of thinning due to insufficient foaming on the terminal side of the product, a foamed resin molded product with excellent dimensional accuracy is obtained, and there are no gaps or steps in the joint part between them, and the appearance is excellent. An object of the present invention is to provide a bonded structure of a foamed resin molded product that can obtain a stable bonding posture.

  In order to solve the above-mentioned problems, the present invention includes a step of reversing the movable mold after injecting and filling a foamed resin material into a cavity defined between the movable mold and the fixed mold. This is a bonding structure between a foamed resin molded product that is foam-molded to a required shape and a resin molded product molded into the required shape, and is welded upright on the back of the resin molded product A foamed resin molded product that inserts a boss into the mounting hole of the foamed resin molded product and abuts the reinforcing rib around the welding boss against the mounting seat surface around the mounting hole to join the foamed resin molded product and the resin molded product. In the joint structure, the mounting seat surface of the foamed resin molded product is integrated with a rib at a position where the interference with the reinforcing rib of the resin molded product can be avoided and closer to the terminal, and when the movable side mold is retracted. Because of the anchor effect of the ribs, Is plate thickness is effectively secured in end side, characterized in that it has to suppress the rolling defects of the resin molded article at the abutting action of the bearing seat surface and the reinforcing ribs.

  Here, the movable mold in the molding mold can be moved by a predetermined stroke by a cylinder or a press ram so that the mold can be opened and clamped with respect to the fixed mold, and in particular, an injection filling process of the foamed resin material A first mold position that secures a narrow mold clearance between the movable mold and the fixed mold, and a second mold that retracts the movable mold by a predetermined stroke from the first mold position to secure a foaming space. The stroke of the movable mold is set so that the mold position can be positioned. On the other hand, the fixed mold is provided with resin passages such as a hot runner and a valve gate in order to supply the foamed resin material into the cavity. A concave portion is provided on the outer periphery of the cavity of the movable mold so as to follow the movable mold when the movable mold is opened, and it is movable on the end side of the foamed resin molded product by the anchor effect of the rib corresponding to the concave portion. Follow the side mold. Further, the rib formed on the product terminal side has a function of reinforcing rigidity.

  Further, the combination of the foamed resin molded product and the resin molded product to be joined is, for example, a relatively large interior component that is mounted on the interior surface of a vehicle side wall panel such as a door trim, a rear side trim, and a luggage side trim. Thus, it is applied to a structure in which each part such as a trim upper and a trim lower upper and lower divided body, or a trim upper, a trim center, and a trim lower upper and lower divided body is joined and fixed. Taking the upper and lower parts of the trim upper and trim lower as an example, the trim upper is made of foamed resin molded product, the trim lower is made of resin molded product, and the welding boss protruding from the back of the trim lower is inserted into the mounting hole of the trim upper Then, the two are integrated by fastening the tip by caulking or the like.

  It can also be applied to a structure in which a pocket cover is attached to the door trim body. In this case, the door trim main body is made of a foamed resin molded product, the pocket cover is made of a resin molded product, the pocket cover bosses are inserted into the mounting holes of the door trim main body, and the bosses are fastened to assemble the two. .

  And, according to the joint structure of the foamed resin molded product and the resin molded product according to the present invention, the flange thickness for the joint of the foamed resin molded product that becomes the mounting seat surface of the resin molded product is the plate thickness of the end portion of the rib. Because it is sufficiently secured by the anchor effect, the resin molded product and the foamed resin molded product can be positioned with a stable and reliable bonding posture, the resin molded product does not crack, and there is a gap between the two. Alternatively, since no step is generated, the appearance of the mating portion is excellent.

  As described above, according to the joint structure of the foamed resin molded product according to the present invention, a molding method for molding the foamed resin molded product by changing the mold clearance during injection filling and the mold clearance during foam molding is adopted. In particular, a concave part is provided in the movable mold on the outer periphery of the cavity, and when the movable mold is retracted, the portion filled in the concave part follows the operation of the movable mold. Since it is possible to eliminate the lack of lack of wall and secure a sufficient thickness of the terminal portion, it is possible to increase the dimensional accuracy of the foamed resin molded product, particularly the dimensional accuracy of the terminal portion. Therefore, in the joint structure with the resin molded product, the joint posture can be maintained satisfactorily and reliable positioning can be expected, so that there is no gap or step in the mating part, and the appearance design of the mating part is improved. It has the effect of being able to.

  Hereinafter, embodiments of the joint structure for foamed resin molded products according to the present invention will be described in detail with reference to the accompanying drawings. Note that the gist of the present invention is as described in the scope of claims, and the contents of the embodiments described below are merely examples of the present invention.

  FIG. 1 to FIG. 14 show an embodiment of the present invention. FIG. 1 is a front view showing a luggage side trim having an upper and lower split structure to which a joint structure of foamed resin molded products according to the present invention is applied. FIG. 3 is a perspective view showing the vicinity of the mounting seat surface of the trim upper in the luggage side trim, and FIG. 4 is a perspective view of the trim lower in the luggage side trim. FIG. 5 is an explanatory diagram showing a schematic configuration of a molding die used when molding a trim upper in the luggage side trim, and FIG. 6 is a cavity outer peripheral shape in the molding die. FIG. 7 to FIG. 10 are explanatory views showing respective steps of the trim upper forming method in the luggage side trim, and FIG. 11 to FIG. 14 is a respective explanatory view showing a modification of the welding structure of the foamed resin molded article according to the present invention.

  1 to 4, the luggage side trim 10 is an interior part that is attached to the interior surface side of the side wall panel of the luggage room of the vehicle, and is composed of an upper and lower divided body of a trim upper 20 and a trim lower 30. Each of the trim upper 20 and the trim lower 30 includes various functional parts such as a multi-functional hook for suspending equipment, an air grill for air conditioning, a speaker grill, etc. separately from the trim upper 20 or the trim lower 30, or Although they are provided integrally, they are not the gist of the present invention, and therefore, these functional parts and their mounting structures are omitted here.

  By the way, the trim upper 20 uses a foamed resin molded product, and this foamed resin molded product uses a material in which a foaming agent is mixed in a synthetic resin. For example, usable synthetic resins include polyethylene resins, polypropylene resins, polystyrene resins, polyethylene terephthalate resins, polyvinyl alcohol resins, vinyl chloride resins, polyamide resins, polyacetal resins, polycarbonate resins, and ionomer resins. Resin, acrylonitrile / butadiene / styrene (ABS) resin, and the like. In addition, as a foaming agent mixed with respect to a synthetic resin, organic foaming agents, such as azodicarbonamide, or inorganic foaming agents, such as sodium bicarbonate, can be used. Furthermore, although a molding method will be described later, an injection molding method is adopted. On the other hand, the trim lower 30 is formed by injection molding a synthetic resin material using a normal resin molded product employing an injection molding method and omitting the foaming agent of the foamed resin molded product in the trim upper 20. .

  Next, based on FIG. 2 thru | or FIG. 4, the junction structure of the trim upper 20 and the trim lower 30 is demonstrated. First, as is clear from the cross-sectional view shown in FIG. 2 and the perspective view shown in FIG. 3, the trim upper 20 is composed of a two-layer structure of a skin layer 21 on the surface and a foam layer 22 inside thereof. In order to partially overlap the trim lower 30, a joining flange 23 is formed on the lower edge, and in particular, a mounting seat surface 24 is set at a fixed portion with the trim lower 30. The mounting holes 25 are opened, and ribs 26 that are long in the vertical direction are formed so as to protrude toward the indoor side at the four corners of the mounting seat surface 24 so as to surround the mounting holes 25.

  On the other hand, the trim lower 30 is formed with a welding boss 31 for insertion into the mounting hole 25 of the trim upper 20, and a cross-shaped reinforcing rib 32 is integrally formed around the welding boss 31. It has become. The cross-shaped reinforcing rib 32 is brought into contact with the mounting seat surface 24 of the trim upper 20 so that the trim upper 20 and the trim lower 30 are firmly brought into contact with each other. The trim upper 20 and the trim lower 30 are firmly joined and integrated by performing ultrasonic welding caulking as shown in FIG. The rib 26 is set closer to the end of the mounting seat surface 24 at a position where interference with the reinforcing rib 32 is avoided.

  As described above, in the present invention, the ribs 26 are formed at the four corners of the mounting seat surface 24 in the trim upper 20, and the rigidity of the mounting seat surface 24 is enhanced by the ribs 26. The initial shape can be maintained for a long time without deformation. Further, as will be described later, the ribs 26 function effectively so that the plate thickness on the terminal side of the mounting seat surface 24 can be secured satisfactorily when the trim upper 20 is formed. In a state where the trim upper 20 and the trim lower 30 are joined, the reinforcing ribs 32 of the trim lower 30 are firmly attached to and supported by the mounting seat surface 24 of the trim upper 20, and a firm joining posture of both is obtained. For this reason, the upper end side of the trim lower 30 does not roll, and a gap, a step, or the like does not occur at the mating portion between the trim upper 20 and the trim lower 30.

  Next, FIGS. 5 and 6 show a schematic configuration of a molding die 40 used when molding the trim upper 20 in the luggage side trim 10. The molding die 40 is fixed to the movable side die 50. The side mold 60 and the injection machine 70 are generally configured. More specifically, the movable mold 50 is driven by the press ram 51 so as to take three positions, namely, a mold opening position and a mold clamping position, as well as a foam molding position. On the other hand, the fixed-side mold 60 is supplied with the foamed resin material M on the mold surface through the hot runner 61 and the valve gate 62 serving as a resin passage for the foamed resin material M supplied from the injection machine 70, and foamed after molding. An ejector pin 63 for projecting the trim upper 20 which is a resin molded product is internally provided.

  Thus, the trim upper 20 is formed along the cavity C shape defined between the movable side mold 50 and the fixed side mold 60. In particular, as shown in FIG. A recess 52 is formed in the movable mold 50 corresponding to the outer periphery, for example, the terminal portion of the mounting seat surface 24. The recesses 52 match the shape of the ribs 26 formed at the four corners of the mounting seat surface 24. When the foamed resin material M enters the recesses 52 and the movable side mold 50 retreats. This portion follows the movable-side mold 50 by the anchor effect, so that a sufficient thickness can be secured for the end portion of the trim upper 20.

  Next, a molding method capable of accurately molding the trim upper 20 that is a foamed resin molded product will be sequentially described with reference to FIGS. First, as shown in FIG. 7, the movable die 50 is clamped with respect to the fixed die 60 by the press ram 51. When the molding die 40 is in the clamping position, the hot runner 61, The foamed resin material M is injected and filled into the cavity C through the valve gate 62. At this time, although not shown, it is also possible to adopt a counter pressure method in which air is forcibly introduced from the outside into the cavity C and the resin is filled in the cavity C so that the foamed resin material M does not undergo a foaming reaction.

  Next, when the injection filling process of the foamed resin material M is completed, as shown in FIG. 8, the movable side mold 50 moves backward by a minute stroke in the mold opening direction. In the backward movement of the movable mold 50, the unfoamed half-molded product P is accommodated in the cavity C, and a foaming space S corresponding to the backward stroke of the movable mold 50 is secured. Become. Further, as shown in FIG. 9, the foamed reaction is induced in the unfoamed half-molded product P so that the skin layer 21 and the foamed layer 22 have a desired thickness in the foamed space S in which the mold clearance is set large. To be molded. At this time, as shown in FIG. 10, a recess 52 is formed along the outer periphery of the cavity C of the movable mold 50, and a rib 26 corresponding to the recess 52 is formed. The semi-molded product P can follow the mold surface of the movable mold 50 and sufficiently secure the thickness of the terminal portion. Therefore, the trim upper 20 can be molded with high accuracy, and the bonding posture with respect to the trim lower 30 can be maintained well over a long period of time.

  Next, FIGS. 11 to 14 show modifications of the present invention. As shown in FIG. 11, cylindrical ribs 26A are formed at the four corners of the mounting seat surface 24 of the trim upper 20. Yes. Even in this case, the function of strengthening the rigidity and the function of ensuring the plate thickness and eliminating the lack of thinning can be the same as in the above embodiment only by the difference in shape. Further, as shown in FIGS. 12 to 14, the ribs 26 </ b> B and 26 </ b> C formed on the surface of the mounting seat surface 24 in the trim upper 20 are the same as those in the above-described embodiment. A rib 26B is formed at one location, and a rib 26C extending in the lateral direction is formed below the mounting hole 25. The reinforcing ribs 32 in the trim lower 30 are obliquely upward and obliquely downward so as not to interfere with the ribs 26B and 26C. The cross shape is set. In this modified example, the rigidity can be reinforced by the ribs 26B and 26C, and the function of securing the plate thickness is the same as that in the above embodiment.

  In the embodiment described above, the luggage side trim 10 is divided into the upper and lower parts, and the present invention is applied to the joining structure of the trim upper 20 which is a foamed resin molded product and the trim lower 30 which is a resin molded product. However, the present invention is not limited to this, and can be applied to general joint structures between foamed resin molded products and resin molded products. For example, in addition to the luggage side trim 10 composed of the trim upper 20 and the trim lower 30, the interior trim adopting a split structure such as a door trim and a rear side trim, as well as a door trim body composed of a foamed resin molded product, from a resin molded product. It can also be applied to a structure in which the pocket cover is joined and integrated by fastening and fixing the boss. Furthermore, it is also possible to employ a counter pressure method for supplying compressed air into the cavity C when the foamed resin material M is injected and filled.

It is a front view which shows the luggage side trim of the upper and lower divided structure to which the joining structure of the foamed resin molded product which concerns on this invention is applied. It is the II-II sectional view taken on the line in FIG. It is explanatory drawing which shows the shape of the mounting seat surface of the trim upper in the joining structure of the trim upper and trim lower shown in FIG. FIG. 3 is a partially cutaway perspective view showing a welding boss and a reinforcing rib of the trim lower in the joint structure of the trim upper and the trim lower shown in FIG. 2. It is a schematic diagram which shows the whole structure of the shaping die used when shape | molding the trim upper in the luggage side trim shown in FIG. It is an expanded sectional view which shows the structure of the attachment seat surface vicinity part in the shaping die shown in FIG. It is explanatory drawing which shows the injection filling process of the foamed resin material in the shaping | molding method of the trim upper in the luggage side trim shown in FIG. It is explanatory drawing which shows the reverse operation state in the shaping | molding method of the trim upper in the luggage side trim shown in FIG. It is explanatory drawing which shows the foam molding process in the molding method of the trim upper in the luggage side trim shown in FIG. It is explanatory drawing which shows the molding state of the attachment seat surface in the foam molding process of the trim upper shown in FIG. It is explanatory drawing which shows the modification of the mounting seat surface of the trim upper to which this invention structure is applied. It is sectional drawing which shows the modification of the joining structure of the trim upper and trim lower to which this invention structure is applied. It is a perspective view which shows the attachment seat surface of the trim upper in the modification of the joining structure shown in FIG. It is explanatory drawing which shows the welding boss | hub of the trim lower in the modification of the joining structure of the trim upper shown in FIG. 12, and a trim lower. It is a front view which shows the conventional luggage side trim. It is XVI-XVI sectional view taken on the line in FIG. It is explanatory drawing which shows the whole structure of the shaping die used for shaping | molding of the trim upper in the conventional luggage side trim. It is explanatory drawing which shows the malfunction at the time of shaping | molding of the trim upper in the conventional luggage side trim, and the malfunction at the time of joining.

Explanation of symbols

10 Luggage side trim 20 Trim upper (foamed resin molded product)
21 Skin Layer 22 Foamed Layer 23 Joint Flange 24 Mounting Seat 25 Mounting Hole 26 Rib 30 Trim Lower (Resin Molded Product)
31 welding boss 32 reinforcing rib 40 molding die 50 movable die 51 press ram 52 recess 60 fixed die 61 hot runner 62 valve gate 63 ejector pin 70 injection machine C cavity M foam resin material P semi-molded product S foam space

Claims (1)

After the foamed resin material (M) is injected and filled into the cavity (C) defined between the movable mold (50) and the fixed mold (60), the movable mold (50) is retracted. By operating, a foaming space (S) is secured, and a foamed resin molded product (20) formed by foam molding into a required shape and a resin molded product (30) molded into the required shape are joined structures. The welding boss (31) standing on the back surface of the resin molded product (30) is inserted into the mounting hole (25) of the foamed resin molded product (20), and the mounting seat surface (24) around the mounting hole (25) is inserted. In the joint structure of the foamed resin molded product (20) in which the reinforcing rib (32) around the welding boss (31) is abutted against the foamed resin molded product (20) and the resin molded product (30).
The mounting seat surface (24) of the foamed resin molded product (20) is integrated with a rib (26) at a position where interference with the reinforcing rib (32) of the resin molded product (30) can be avoided and closer to the terminal. When the movable mold (50) is retracted, the anchor effect of the rib (26) ensures an effective plate thickness on the terminal side of the mounting seat surface (24), and the mounting seat surface (24) and the reinforcing rib The joint structure of a foamed resin molded product, wherein the rolling failure of the resin molded product (30) is suppressed by the abutting action with (32).

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