JP2009166458A - Method and apparatus for molding foamed resin molding - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To prevent a part connected to the pressurization attachment part of a foamed main part from sinking to the side of the foamed main part by pressurization power during attachment to a mating member when the pressurization attachment part in a state of non-foaming or a low expansion ratio is molded to protrude integrally from the foamed main part of a foamed resin molding. <P>SOLUTION: When the foamed main part 11 of a work 10 is foamed by core-backing a mold part 25 corresponding to the foamed main parts of the molds by the use of an expandable resin packed in molds 21 and 25, and the pressurization attachment part 13 made of a foaming suppressing resin part attached to a mating member by being pressurized is molded to protrude integrally from the foamed main part, in the part connected to the pressurization attachment part of the foamed main part, a pressurization attachment part base 14 which is molded while a core-backing quantity rate when the mold part is core-backed is set to be smaller than that of the other part of the foamed main part is formed. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a molding method and a molding apparatus for a foamed resin molded product formed from a foamable resin containing a foaming agent in a resin.

  Conventionally, in the field of various industrial parts such as automobile parts, foamed resin molded products excellent in light weight and heat insulating properties have been widely used. Such foamed resin molded products are manufactured by selecting suitable materials 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 injecting a foamable resin containing a foaming agent into the resin into the molding cavity of the molding die, the core of the molding die is moved so as to increase the volume of the cavity A molding method (so-called core back method) in which foaming of the foamable resin is promoted by causing the foaming resin to be promoted is known. It is known that by using this core back method, it is possible to obtain a foamed resin molded product having a small variation in the foamed cell diameter.

  For example, in Patent Document 1, a fiber-containing molten thermoplastic resin containing a foaming agent is used as a material, and after the material resin is injected into the cavity of the mold, the movable mold is expanded in the direction in which the volume of the mold cavity increases. A fiber-reinforced lightweight resin molded product formed by expanding the fiber-containing molten thermoplastic resin by retreating the fiber and a method for producing the same are disclosed.

  Further, for example, Patent Document 2 intends to solidify only a specific portion requiring strength while maintaining the properties of the foam as a whole, and injecting a foamable resin into the cavity of the mold. After foaming the foamed resin, move the core part of the mold so that the volume of the specific part of the cavity is reduced or eliminated, so that only the specific part that needs strength is solidified. A forming method is disclosed.

  By the way, when the foamed resin molded product is used by being attached to another part or member (hereinafter referred to as a mating member), the mounting structure is a protruding mounting portion having a predetermined height protruding from the surface of the foamed resin molded product. A structure in which the (pressure attaching portion) is integrally formed and the pressure attaching portion is brought into contact with a mating member and attached by pressure is well known.

  For example, air-conditioning ducts attached to air-conditioning equipment for vehicles such as automobiles often use foamed resin molded products with excellent lightness and heat insulation properties, but this air-conditioning duct is located at the front end of the passenger compartment. When installing through the back of the panel, the pressure mounting part of a predetermined height protruding from the mounting seat surface is integrally formed on the mounting seat surface of the air conditioning duct of the foamed resin molded product, and the pressure mounting The air conditioning duct is attached (welded) to the back of the instrument panel by applying pressure welding to the back of the instrument panel and applying vibration welding to the contact part in a pressurized state. It is possible.

  When the foamed resin molded product is attached to the mating member with the protruding pressure mounting portion in this way, the pressure mounting portion itself that requires strength is generally in contact with the mold during the molding process of the foamed resin molded product. Various conditions are set so that foaming is suppressed by the cooling effect caused by this, and the non-foamed state (that is, the solid state) or the foaming ratio is maintained at a very low state.

  FIG. 11 and FIG. 12 are explanatory diagrams schematically showing a protrusion-like pressure mounting portion according to the conventional example and foam molding around it, and FIG. 11 shows a state in which foam resin is filled in the molding cavity. Shows the state in which the volume of the molding cavity is expanded to foam the material resin.

The molding cavity 229 formed by the fixed mold 221 and the movable mold 225 is filled with a foamable resin 231 (see FIG. 11), and then the movable mold 225 is retracted to perform so-called core back, thereby forming the molding cavity 229. Is expanded and the material resin 231 is foamed, and the main body portion 211 (foaming main body portion) of the molded product 210 is foam-molded (see FIG. 12). The contact area with the fixed mold 221 is very large due to the protrusion in the fixed mold 221, and the cooling effect of the fixed mold 221 is very high. The magnification is maintained. In addition, the foaming of the surface of the foaming main body portion 211 that is in contact with the molds 221 and 225 and the vicinity thereof is also suppressed by the heat deprived by the molds 221 and 225. Maintained.
Japanese Patent Laid-Open No. 11-156881 Japanese Patent Laid-Open No. 2002-067111

  In the foamed resin molded product 210 molded in this way, the pressure mounting portion 213 itself has a high strength and / or strength by suppressing foaming and maintaining the non-foamed state or the low foaming ratio state as described above. Although it has rigidity, the portion that supports the pressure mounting portion 213 of the foam main body portion 211 (that is, the portion that continues to the pressure mounting portion 213) is molded in a foamed state, so the pressure mounting portion Compared to 213, the strength and / or rigidity is considerably low.

  When the foamed resin molded product 210 is attached to the mating member 216 by vibration welding, with the tip of the pressure mounting portion 213 brought into contact with the surface of the mating member 216 made of resin, as schematically shown in FIG. As shown in FIG. 14, the portion 212 continuing to the pressure mounting portion 213 of the foam main body 211 sinks to the foam main body 211 due to the pressure applied during vibration welding, and the mounting seat surface (the pressure mounting portion 213 is The supporting surface is also deformed, and the pressure attachment portion 213 is recessed into the foam main body portion 211. For this reason, a necessary frictional force cannot be obtained between the front end of the pressure mounting portion 213 and the surface of the mating member 216, which causes a problem of poor welding. In the case where such a problem does not occur, as shown in FIG. 15, the portion 212 continuing to the pressure mounting portion 213 of the foam main body 211 is not deformed, and the tip of the pressure mounting portion 213 is not formed. Is welded to the surface of the counterpart member 216 without hindrance.

  This invention has been made in view of the above technical problem, and when molding the pressure mounting portion in a non-foamed state or a low foaming magnification state so as to protrude integrally from the foamed main body portion of the foamed resin molded product, It is a basic object to prevent a portion continuing to the pressure mounting portion of the foam main body portion from sinking into the foam main body portion side due to the applied pressure at the time of attachment to the mating member.

For this reason, the invention according to claim 1 of the present application (the first invention) corresponds to the foam main body portion of the foamed resin molded product corresponding to the foam main body portion of the mold by the foamable resin filled in the mold. Foam molding is performed by making the mold part to be cored back, and the pressure mounting part composed of the foam suppression resin part that is attached to the mating member when pressed is formed so as to protrude integrally from the foam main body part. A method for molding a foamed resin molded product, wherein the molding die portion is core-backed to a portion continuous with the pressure mounting portion of the foam main body portion rather than other portions of the foam main body portion. A pressure attachment base is formed that is formed with a core back amount rate set to a small value.
Here, the “foaming suppression resin part” is not only a part where foaming is suppressed and kept in a non-foamed state (solid state), but even when foaming, the foaming ratio is kept very low. The "core back amount ratio" is the molding cavity after the core back with respect to the molding cavity thickness before the core back when the molding die part corresponding to the foaming main body part of the molding die is cored back. The ratio of thickness shall be said.

  The invention according to claim 2 of the present application (second invention) is characterized in that, in the first invention, the pressure attachment base is formed wider than the pressure attachment. Is.

  Furthermore, the invention according to claim 3 of the present application (third invention) is the first or second invention, in the mold part corresponding to the pressure mounting part of the mold prior to the core back. The pressure mounting part is formed by cooling the foamable resin by the mold part.

  Furthermore, the invention according to claim 4 of the present application (fourth invention) is characterized in that, in any one of the first to third inventions, the foamable resin contains a physical foaming agent. It is what.

  Furthermore, the invention according to claim 5 of the present application (fifth invention) is characterized in that, in the fourth invention, the physical foaming agent is a fluid in a supercritical state.

Further, the invention according to claim 6 of the present application (sixth invention) is a mold having a fixed mold and a movable mold which are combined with each other to form a mold cavity, and a foaming property in which a foaming agent is contained in the resin. Injection means for injecting resin into the molding cavity; and movable mold drive means for moving the movable mold relative to the fixed mold so as to change the volume of the molding cavity; and Foam molding is performed by injecting into the molding cavity and core-backing the foaming body part of the foamed resin molded product with the foaming body part of the movable mold by the foamable resin filled in the molding cavity. And forming a pressure attachment portion composed of a foam suppression resin portion attached to the mating member by being pressurized so as to protrude integrally from the foam main body portion. A molding apparatus for a molded product, wherein the core back amount rate when the molding die part is cored back to the part continuing to the pressure mounting part of the foaming body part rather than the other part of the foaming body part Is further provided with a pressure attachment base portion forming means for forming a pressure attachment portion base portion that is set to be small.
Here, the “foaming suppression resin part” is not only a part where foaming is suppressed and kept in a non-foamed state (solid state), but even when foaming, the foaming ratio is kept very low. The "core back amount ratio" is the molding cavity after the core back with respect to the molding cavity thickness before the core back when the molding die part corresponding to the foaming main body part of the molding die is cored back. The ratio of thickness shall be said.

  Furthermore, the invention according to claim 7 of the present application (seventh invention) is that, in the sixth invention, the pressure attachment base portion forming means is a pressure attachment portion base wider than the pressure attachment portion. It is characterized by forming.

  Furthermore, the invention according to claim 8 of the present application (eighth invention) is the molding die corresponding to the pressure mounting portion of the fixed die prior to the core back in the sixth or seventh invention. The pressure mounting part is formed by cooling the foamable resin in the part by the mold part.

  Still further, an invention according to claim 9 of the present application (ninth invention) is any one of the sixth to eighth inventions, wherein the injection means injects a foamable resin containing a physical foaming agent. It is characterized by that.

  Furthermore, the invention according to claim 10 of the present application (tenth invention) is the ninth invention, wherein the injection means injects a foamable resin containing a fluid in a supercritical state as the physical foaming agent. , Is characterized by that.

  According to the first invention of the present application, the core back amount rate when the molding die portion is core-backed is set smaller than the other portion of the foam main body portion in the portion continuing to the pressure mounting portion of the foam main body portion. The strength and / or rigidity of the portion continuing to the pressure mounting portion of the foamed main body portion can be increased by forming the pressure mounting portion base that is molded. Thereby, it can suppress that the part which continues to the pressurization attachment part of a foaming main-body part sinks to the foaming main-body part side resulting from the applied pressure at the time of attachment to a counterpart member, and it can prevent that it causes attachment failure. .

  Further, according to the second invention of the present application, by forming the pressure attachment base portion wider than the pressure attachment portion, a wider area of a portion continuous with the pressure attachment portion of the foam main body portion. The strength and / or rigidity can be increased, and the operational effects of the first invention can be obtained more reliably.

  Furthermore, according to the third invention of the present application, basically the same operational effects as those of the first or second invention can be obtained. In particular, prior to the core back, the pressure mounting portion is molded by cooling the foamable resin in the molding die portion corresponding to the pressure mounting portion of the mold by the molding die portion. The pressure mounting portion can be reliably formed by simple means.

  Still further, according to the fourth invention of the present application, when the foamable resin contains a physical foaming agent, the effects of any one of the first to third inventions can be more reliably achieved. Can do.

  Still further, according to the fifth invention of the present application, since the physical foaming agent is a fluid in a supercritical state, the operational effects of the fourth invention can be further promoted. By using a fluid in a supercritical state as the physical foaming agent, a foamed resin molded product having finer foam cells can be molded, and the overall physical properties of the foamed resin molded product can be further improved.

  Still further, according to the sixth invention of the present application, the pressure attaching part base forming means is configured so that the part of the foaming main body part continuous with the pressure attaching part is more than the other part of the foaming main body part. By forming the pressure attachment base that is molded with the core back amount rate set to be small when the core is made back, the strength and / or rigidity of the portion continuing to the pressure attachment of the foam main body is increased. Can be increased. Thereby, it can suppress that the part which continues to the pressurization attachment part of a foaming main-body part sinks to the foaming main-body part side resulting from the applied pressure at the time of attachment to a counterpart member, and it can prevent that it causes attachment failure. .

  Still further, according to the seventh invention of the present application, since the pressure attachment base portion is formed wider than the pressure attachment portion, a wider portion of the portion continuing to the pressure attachment portion of the foam main body portion is formed. The strength and / or rigidity of such a region can be increased, and the operational effects of the sixth invention can be obtained more reliably.

  Furthermore, according to the eighth invention of the present application, basically, the same operational effects as those of the sixth or seventh invention can be achieved. In particular, prior to the core back, the pressure mounting portion is molded by cooling the foamable resin in the molding die portion corresponding to the pressure mounting portion of the fixed mold by the molding die portion. The pressure mounting portion can be reliably formed by simple means.

  Still further, according to the ninth invention of the present application, by injecting a foamable resin containing a physical foaming agent in the injection means, the operational effect of any one of the sixth to eighth inventions is further improved. It can be played reliably.

  Still further, according to the tenth invention of the present application, the effect of the ninth invention can be promoted by injecting a foamable resin containing a supercritical fluid as a physical foaming agent by the injection means. it can. By using a fluid in a supercritical state as the physical foaming agent, a foamed resin molded product having finer foam cells can be molded, and the overall physical properties of the foamed resin molded product can be further improved.

  Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings. In the present embodiment, for example, it is assumed that an air conditioning duct attached to an air conditioner for a vehicle such as an automobile is formed of a foamed resin molded product, and this air conditioning duct is attached to the back of an instrument panel located at the front end of the passenger compartment. Is about the case.

  FIG. 1 is a cross-sectional explanatory view showing a cross-sectional structure of the air conditioning duct as a foamed resin molded product according to the present embodiment. As shown in the figure, the air-conditioning duct 1 includes a duct main body 2 having a substantially semicircular cross section having a predetermined thickness, and mounting flange portions formed at upper and lower end portions of the duct main body 2. 3, and each mounting flange portion 3 is integrally provided with a projecting mounting portion 4 (pressure mounting portion) having a predetermined height.

  In the present embodiment, the entire air conditioning duct is molded as an integral foamed resin molded product 1, and the pressure mounting portion 4 integrally molded with the mounting flange portion 3 is pressed against the back surface of the instrument panel 6. By applying the vibration welding method and applying vibration to the contact portion in a pressurized state, the air-conditioning duct 1 is welded to the back surface of the instrument panel 6, and the ventilation path 9 is formed between the two 1 and 6. It has come to be. Thus, the air-conditioning duct 1 which was lightweight and excellent in heat insulation is obtained by making the air-conditioning duct 1 into the foamed resin molded product.

  Next, the foamed resin molding method used for molding the air conditioning duct will be described. In this description, as a foamed resin molded product, a workpiece in which a pressure mounting portion is integrally formed with a substantially plate-shaped main body portion is used as a simplified model. FIG. 2 is a cross-sectional view schematically showing a molding apparatus for molding the workpiece with foamed resin. 3 is an enlarged cross-sectional view showing an enlarged main part of FIG. 2 before the core back, and FIG. 4 is an enlarged cross-sectional view showing an enlarged main part of FIG. 2 after the core back.

  As can be seen from FIG. 4, the foamed resin molded product 10 (workpiece) includes a substantially plate-like main body 11 (foaming main body) and a protruding mounting portion 13 (a predetermined height projecting from the foaming main body 11). The pressure attachment portion) is integrally formed. Further, as will be described later, in the foamed resin molded product 10, the core back amount ratio is set to be smaller than the other part of the foamed main body part 11 in the part continuing to the pressure attachment part 13 of the foamed main body part 11. A pressure attachment base 14 is formed.

  As shown in FIG. 2, the molding apparatus M includes a mold 20 that can be opened and closed, and an injection apparatus 30 that serves as injection means for injecting a foamable resin into a molding cavity 29 in the mold 20. The mold 20 includes a fixed mold 21 that is always kept stationary, and a movable mold 25 that is movable with respect to the fixed mold 21 in the opening and closing direction of the mold 20. By combining each other, a molding cavity 29 corresponding to the workpiece shape is formed. The movable mold 25 is connected to a movable drive mechanism (not shown), and can be moved in the opening / closing direction of the mold 20 (arrows Ya and Yb in FIG. 2) by the movable drive mechanism. .

  A columnar convex portion 22 having a predetermined height is formed in the central portion of the mold matching surface of the fixed mold 21, while the convex portion 22 of the fixed die 21 is formed in the central portion of the mold matching surface of the movable mold 25. A concave portion 26 to be combined is formed. By combining the fixed mold 21 and the movable mold 25, the inner peripheral surface 26 s of the concave section 26 of the movable mold 25 slides in the opening / closing direction of the molding mold 20 outside the outer peripheral surface 22 s of the convex section 22 of the fixed mold 21. It is movably fitted. In this fitted state, a mold cavity 29 is formed by the mold surface 22 f of the convex portion 22 of the fixed mold 21 and the mold surface 26 f and the inner peripheral surface 26 s of the concave portion 26 of the movable mold 25.

  In the mold 20, the convex portion 22 of the fixed mold 21 is provided with a pressure mounting portion forming groove 22 g dug from the mold surface 22 f corresponding to the pressure mounting portion 13 of the foamed resin molded product 10. In the concave portion 26 of the mold 25, a pressure mounting portion base portion dug from the mold surface 26 f corresponding to the pressure mounting portion base portion 14 formed in a portion continuous with the pressure mounting portion 13 of the foamed resin molded product 10 is formed. The groove portion 26g for use is provided, and the pressure mounting portion base forming groove portion 26g has a width D2 wider than the width D1 of the pressure mounting portion forming groove portion 22g. With the molding die 20 closed, the molding cavity thickness in the opening / closing direction of the molding die 20 is such that the molding cavity thickness H2 of the portion having the groove 26g on the die surface 26f is the portion of the die surface 26f having no groove 26g. It is thicker than the molding cavity thickness H1.

  A clearance (clearance) between the outer peripheral surface 22 s of the convex portion 22 of the fixed mold 21 and the inner peripheral surface 26 s of the concave portion 26 of the movable mold 25 is slid smoothly in the opening / closing direction of the movable mold 25 with respect to the fixed mold 21. It is set within a range in which the sealing property can be maintained so that the foamable resin filled in the molding cavity 29 does not leak to the outside in a state where the molding cavity 29 is formed.

  Further, in a state where the molding cavity 29 is formed by the fixed mold 21 and the movable mold 25, the movable mold 25 is moved in the mold opening direction of the molding mold 20 (the direction of the arrow Ya in FIG. 4) by the movable mold driving mechanism (not shown). The volume of the molding cavity 29 can be increased by moving it by a predetermined amount E. After injecting the foamable resin into the molding cavity 29, the movable mold 25 is moved by a predetermined amount E in the mold opening direction to increase the volume of the molding cavity 29, thereby promoting foaming of the foamable resin in the cavity 29. So-called core back can be performed. The movement amount E of the movable mold 25 in the core back is set to a predetermined value within a range in which the inner peripheral surface 26s of the concave portion 26 of the movable mold 25 does not separate from the outer peripheral surface 22s of the convex portion 22 of the fixed mold 21. . The core back method is basically the same as a conventionally known method.

  In the present embodiment, since the pressure mounting portion base forming groove portion 26g is provided so as to correspond to the pressure mounting portion forming groove portion 22g, specifically, the movable die 25 is moved in the mold opening direction. When the volume of the molding cavity 29 is increased by moving a predetermined amount E to promote foaming of the foamable resin, the core back amount ratio is small in the portion continuing to the pressure mounting portion 13 of the foam main body portion 11. A pressure mounting base 14 that is set and molded is formed. Here, the “core back amount rate” refers to the mold cavity thickness before the core back when the mold part corresponding to the foaming main body part 11 of the mold 20, specifically, the movable mold 25 is core-backed. The ratio of the thickness of the molding cavity after the core back shall be said.

  As shown in FIG. 4, when the movable mold 25 is moved by a predetermined amount E in the mold opening direction of the mold 20 to increase the volume of the mold cavity 29, the part of the mold 20 having the groove 26 g on the mold surface 26 f is expanded. The molding cavity thickness in the opening / closing direction is H2 + E, and the molding cavity thickness in the opening / closing direction of the molding die 20 at the portion where the mold surface 26f does not have the groove 26g is H1 + E. As a result, the core back amount rate of the molding cavity 29 is (H2 + E) / H2 in the portion of the molding cavity 29 where the groove 26g is on the mold surface 26f, and the portion of the mold surface 26f where the groove 26g is not present. The core back amount ratio of the cavity 29 is (H1 + E) / H1, and the core back amount ratio of the molding cavity 29 is set small by providing the groove portion 26g on the mold surface 26f.

  The injection device 30 is for injecting a foamable resin containing a foaming agent into a resin into the molding cavity 29 of the mold 20, and includes a cylinder 33 for kneading and melting a material resin 32 supplied as resin pellets, for example. ing. A rotary screw 34 is disposed inside the cylinder 33, and although not specifically shown at the rear end of the screw 34, a rotary drive mechanism that rotates the screw 34 and the screw 34 are moved forward. An injection mechanism for moving and injecting the molten resin toward the molding cavity 29 is connected. In the injection device 30, the material resin 32 put into the cylinder 33 is sequentially heated by a heater (not shown) provided around the cylinder 33 and is kneaded by a screw 34.

  The injection device 30 includes a cylinder 35 storing an inert gas such as carbon dioxide or nitrogen, a supercritical fluid generator 36 for bringing the inert gas into a supercritical state, and a cylinder containing the inert gas brought into the supercritical state. A supercritical fluid injecting device 37 for injecting into the inside 33 is attached. Then, the inert gas supplied from the cylinder 35 and brought into the supercritical state by the supercritical fluid generator 36 is injected by the supercritical fluid injector 37 into the resin 32 kneaded and melted in the cylinder 33. A foamable resin 31 containing a foaming agent is formed.

  The foamable resin 31 in the cylinder 33 is injected into the molding cavity 29 of the molding die 20 as the screw 34 is rotated by the rotation driving mechanism and moved forward by the injection mechanism. Specifically, the molding die 20 is provided with a resin passage 24 for injecting the foamable resin 31 toward the molding cavity 29 in the stationary die 21.

  As the material 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.

  In addition, when a physical foaming agent is contained in a resin, it is generally known that the foaming pressure becomes higher and foaming is easier than when a chemical foaming agent is used. Further, by using a fluid in a supercritical state as a physical foaming agent, a foamed resin molded product having finer foam cells can be molded, and the overall physical properties of the foamed resin molded product can be further improved. .

  Although not specifically shown, the molding apparatus M includes a control unit that comprehensively controls the molding apparatus M. The control unit includes, for example, a microcomputer as a main part, and performs various controls such as operation control of the mold 20 and operation control of the injection device 30.

  Next, molding of the foamed resin molded product 10 (work) using the molding apparatus M will be described. First, the movable die 25 is combined with the fixed die 21, and the molding cavity is in a state where the outer portion of the concave portion 26 of the movable die 25 is substantially in contact with the outer portion of the convex portion 22 of the fixed die 21 (see FIG. 2). 29, a foamable resin 31 containing a resin 32 containing a fluid in a supercritical state as a foaming agent is injected from the injection device 30.

  When the foaming resin 31 is filled in the molding cavity 29, as shown in FIG. 3, the protruding pressure mounting portion 13 is fixed because it protrudes into the convex portion 22 of the fixed mold 21. The contact area with the mold 21 is very large, the cooling effect by the molding die portion 22a corresponding to the pressure mounting portion 13 of the fixed die 21 is high, and the foaming is suppressed so that the foaming is suppressed (solid state) or the low foaming ratio state. The pressure mounting portion 13 is molded. Even if the core back is performed in the subsequent process, the pressure attachment portion 13 is maintained in a non-foamed state or a state where the expansion ratio is extremely low, and the strength and / or rigidity of the pressure attachment portion 13 can be increased.

  Thereafter, as shown in FIG. 4, by moving the movable die 25 by a predetermined amount E and performing core back, the molding cavity 29 is expanded and the foamable resin 31 is foamed, and the main body portion 11 ( The foamed main body part) is foam-molded, but a portion 14 (pressurized mounting base) of the foamed main body part 11 that is continuous with the pressure mounting part 13 corresponds to the pressure mounting part 13. Since the pressure mounting portion base forming groove portion 26g is provided and the molding cavity 29 is molded with the core back amount ratio set to be small, foaming is more effectively suppressed than the other portions of the foam main body portion 11. The foaming ratio is maintained at a low state, and the strength and / or rigidity thereof is increased.

  In addition, by applying the core back method to the molding of the foam main body 11 as described above, the foam main body 11 having a small variation in the foam cell diameter can be molded. Further, in this example, compared with the case where a chemical foaming agent is used, generally, a physical foaming agent that increases foaming pressure and easily foams is contained in the resin, but even when such a physical foaming agent is applied. In addition, the pressure attachment portion 13 and the pressure attachment portion base portion 14 were able to effectively suppress foaming. In addition, the pressure mounting portion can be more reliably formed by a relatively simple means. In particular, by using a fluid in a supercritical state as a physical foaming agent, it is possible to form a foamed resin molded product 10 (work) having finer foam cells and further improve the overall physical properties of the work 10. It was.

  When the core back process is finished, the movable mold 25 is further moved in the mold opening direction, the mold opening is performed, and the work 10 molded with the foamed resin is taken out. This completes one cycle of the molding process.

  The workpiece 10 thus molded is attached to a predetermined mating member made of synthetic resin by applying a vibration welding method. FIG. 5 is a cross-sectional view schematically showing the vibration welding process of the workpiece 10 to the mating member. As shown in this figure, the vibration welding apparatus 40 includes a pair of molds (for example, an upper mold 41 and a lower mold 45) provided so as to be able to contact and separate, and the lower mold 45 is made of a synthetic resin counterpart. The member 16 is held. On the other hand, the work 10 is held by the upper die 41 with the pressure mounting portion 13 facing downward via a work holder 42 (holding tool).

  The lower die 45 can be moved back and forth with respect to the upper die 41 by an attached driving device (not shown), and moves forward to the upper die 41 side, thereby connecting the pressure mounting portion 13 of the workpiece 10 and the counterpart member 16. It can be contacted and maintained in a pressurized state. The upper die 41 can be vibrated with a predetermined amplitude and frequency, for example, vertically and horizontally, and obliquely by an attached vibration device (not shown). Then, as shown in FIG. 5, with the workpiece 10 and the counterpart member 16 set on the upper die 41 and the lower die 45, respectively, the lower die 45 is advanced, and the pressure mounting portion 13 and the counterpart member 16 of the workpiece 10 are moved forward. Are brought into a pressurized state, and the upper die 41 is vibrated in that state, whereby the workpiece 10 is welded to the mating member 16 by the pressure mounting portion 13.

In this embodiment, for example, vibration welding is performed under the following conditions.
・ Pressure force: 1-4 MPa
・ Frequency: 100-250Hz
・ Amplitude: 0.5 to 3.0 mm
・ Excitation direction: Up and down, left and right, diagonal ・ Excitation time: Several seconds

  As a result of performing vibration welding under the above conditions, the amount of sinking of the tip surface of the pressure mounting portion 13 is 1 to 2 mm, and as schematically shown in FIG. 14, the pressure mounting portion of the foam main body portion 11. No deformation occurred in the portion continuing to 13, and the tip of the pressure mounting portion 13 could be welded to the surface of the mating member 16 without hindrance.

  As described above, according to the present embodiment, the core back amount rate is smaller in the portion continuing to the pressure mounting portion 13 of the foam main body portion 11 of the work 10 than in the other portions of the foam main body portion 11. By forming the pressure attachment base 14 that is set and molded, the strength and / or rigidity of the portion of the foam main body 11 that is continuous with the pressure attachment 13 can be increased. Thereby, due to the applied pressure at the time of attachment to the counterpart member 16, it is possible to suppress the portion of the foam main body portion 11 continuing to the pressure attachment portion 13 from sinking to the foam main body portion 11 side, resulting in poor attachment. This can be effectively prevented.

  The pressure attachment base 14 formed by setting the core back amount ratio of the foam main body 11 to be small is formed on the entire portion of the foam main body 11 continuous to the pressure attachment 13 or on a part thereof. You may make it do. FIG. 6 is a perspective view showing a molding cavity of a molding die reflecting the shape of the groove for explaining the shape of the pressure mounting portion base forming groove, and FIG. FIG. 6B shows a molding cavity of a molding die for forming a pressure mounting base at the entire portion continuing to the pressure mounting portion of FIG. A molding cavity of a molding die for forming a pressure attachment base portion in part is shown.

  In this embodiment, as shown in FIG. 6A, a portion 29b that projects from the plate-like main body portion 29a of the molding cavity 29 reflecting the shape of the pressure attachment portion forming groove 22g, and a pressure attachment portion base portion A molding die 20 that forms a molding cavity 29 that includes a portion 29c that protrudes in a rectangular shape from a plate-like main body portion 29a of the molding cavity 29 reflecting the shape of the forming groove 26g can be used. As can be seen from the portion 29c reflecting the shape of the groove portion 26g of the molding cavity 29, the pressure attachment portion base forming groove portion 26g is continuously formed along the pressure attachment portion forming groove portion 22g. In the foamed resin molded product 10 molded using the molding die 20 provided with the groove 26g, the pressure attachment base 14 is formed on the entire portion of the foam main body 11 continuous with the pressure attachment 13.

  Further, as shown in FIG. 6B, a portion 29b protruding from the plate-like main body portion 29a of the molding cavity 29 reflecting the shape of the pressure mounting portion forming groove portion 22g, and a pressure mounting portion base forming groove portion A molding die 20 that forms a molding cavity 29 that includes a portion 29d that reflects the shape of 26g and protrudes in a cylindrical shape from the plate-like main body portion 29a of the molding cavity 29 can be used. As can be seen from the portion 29d reflecting the shape of the groove portion 26g of the molding cavity 29, the pressure mounting portion base forming groove portion 26g is not formed continuously along the groove portion 22g but corresponding to a part of the groove portion 22g. It may be. In the foamed resin molded article 10 molded using the molding die 20 provided with the groove 26g, the pressure attachment base 14 is formed in a part of the portion of the foam main body 11 continuous to the pressure attachment 13. . In FIG. 6B, only one portion 29d protruding in a columnar shape of the molding cavity 29 is shown, but the groove 26g may be formed so as to be provided at a predetermined interval.

  In the above-described embodiment, when the foamed resin molded product 10 is molded, the core back amount ratio is set to be smaller than the other parts of the foamed main body part 11 at the part continuing to the pressure mounting part 13 of the foamed main body part 11. In order to form the pressure mounting base 14 to be formed, the movable mounting 25 is provided with a pressure mounting base base forming groove 26g, but the pressure mounting base base forming groove 26 is provided in the fixed mold 21. May be.

  FIG. 7 is a cross-sectional view of an essential part showing a first modification of the mold used in the molding apparatus. FIG. 7A shows a state in which a foamable resin is filled in the molding cavity of the mold. FIG. 7B shows a state in which the volume of the molding cavity is enlarged and the material resin is foamed. In the molding die 50, a fixed die 51 and a movable die 55 are combined with each other to form a molding cavity 59. The fixed die 51 includes a pressure attachment portion forming groove portion 52g and a half portion continuous with the groove portion 52g. A pressure mounting portion base forming groove 53g having a circular cross section and formed wider than the groove 52g is formed by digging from the mold surface 52f of the fixed mold 51.

  When the foamable resin 31 is injected into the molding cavity 59, the foamable resin 31 in the molding die portion 52 a corresponding to the pressure mounting portion of the fixed mold 51 is cooled by the molding die portion 52 a, and the pressure mounting portion 63. Is formed. Then, as shown in FIG. 7B, by moving the movable die 55 backward by a predetermined amount (in the Ya direction in FIG. 7) and performing the core back, the molding cavity 59 is expanded and the foamable resin 31 is foamed. Then, the foam main body 61 of the workpiece 60 is foam-molded.

  However, for a portion 64 (pressure attachment base portion) in a predetermined range that is continuous with the pressure attachment portion 63 in the foam main body portion 61, the fixed die 51 is provided with a pressure attachment portion base forming groove 53g, and the core back amount. Since the ratio is set to be small, the foaming is effectively suppressed as compared with the other parts of the foam main body 61, the foaming ratio is low, and the strength and / or rigidity can be increased. .

  In addition, when molding a foamed resin molded product that is molded so that the pressure mounting portion protrudes integrally from the foam main body portion, the other portion of the foam main body portion is connected to the portion continuing to the pressure mounting portion of the foam main body portion. In order to form a pressure attachment base that is molded with a small core back amount ratio, the difference in thickness in the core back direction of the foam main body can be obtained without providing a pressure attachment base forming groove. The pressure attachment portion may be formed in a portion where the thickness of the foam main body portion in the core back direction is thicker than other portions of the foam main body portion.

  FIG. 8 is a cross-sectional explanatory view showing a second modification of the mold used in the molding apparatus. FIG. 8A shows a state in which a foamable resin is filled in the molding cavity of the mold. FIG. 8B shows a state where the volume of the molding cavity is enlarged and the material resin is foamed. In the molding die 70, a fixed die 71 and a movable die 75 are combined with each other to form a molding cavity 79. A mold surface 72f of the fixed die 71 has a vertical surface portion 72s perpendicular to the opening / closing direction of the molding die 70 and a molding die. The mold surface 76f of the movable mold 75 is inclined with respect to the opening / closing direction of the mold 70, and the mold surface 76f of the movable mold 75 is predetermined with respect to the vertical surface section 76s perpendicular to the opening / closing direction of the molding mold 70 and the opening / closing direction of the molding mold 70. It is provided with an inclined slope portion 76t.

  As shown in FIG. 8A, in the molding die 70, the vertical surface portion 72s of the mold surface 72f and the vertical surface portion 76s of the mold surface 76f are provided facing each other with a predetermined distance therebetween, and the inclined surface portion 72t of the mold surface 72f. A molding cavity 79 having a predetermined thickness is formed so as to face the inclined surface 76t of the mold surface 76f with a predetermined distance.

  Therefore, the molding cavity thickness in the opening and closing direction of the molding die 70 is formed such that the thickness of the molding cavity 79 formed by the slope portions 72t and 76t is larger than the thickness of the molding cavity 79 formed by the vertical surface portions 72s and 76s. ing. Further, the pressure attaching portion forming groove 72g is formed by digging from the mold surface 72f of the fixed mold 71, specifically from the inclined surface 72t of the mold surface 72f.

  Also in the molding die 70, when the foamable resin 31 is injected into the molding cavity 79, the foamable resin 31 in the molding die portion 72a corresponding to the pressure mounting portion of the fixed die 71 is cooled by the molding die portion 72a. Then, the pressure attachment portion 83 is formed. As shown in FIG. 8B, by moving the movable die 75 back by a predetermined amount (in the Ya direction in FIG. 8B) and performing the core back, the molding cavity 79 is expanded and the foamable resin 31 is expanded. Foaming is performed, and the foam main body 81 of the workpiece 80 is foam-molded.

  However, a portion of the foam main body 81 within a predetermined range continuous to the pressure mounting portion 83, specifically, a portion 84 (pressure mounting portion base) formed by a molding cavity formed by the slope portions 72t and 76t. Since the molding cavity thickness in the opening and closing direction of the molding die 70 before the core back is formed thick and the core back amount ratio is set small, the other part of the foam main body 81, specifically, the vertical surface part is formed. Foaming is suppressed more effectively than the portion formed by the molding cavity formed by 72s and 76s, and the molding is performed in a state where the expansion ratio is very low, and the strength and / or rigidity thereof can be increased.

  FIG. 9 is a cross-sectional explanatory view showing a third modification of the mold used in the molding apparatus. FIG. 9A shows a state in which a foamable resin is filled in the molding cavity of the mold. FIG. 9B shows a state where the volume of the molding cavity is enlarged and the material resin is foamed. Also in the molding die 90, the stationary die 91 and the movable die 95 are combined with each other to form a molding cavity 99.

  The mold surface 92f of the fixed mold 91 includes a vertical surface portion 92s perpendicular to the opening / closing direction of the forming die 90 and two inclined surface portions 92t inclined at a predetermined angle with respect to the opening / closing direction of the forming die 90. 92 t is provided symmetrically with respect to the opening / closing direction of the mold 90. On the other hand, the mold surface 96f of the movable die 95 includes a vertical surface portion 96s perpendicular to the opening / closing direction of the forming die 90 and two inclined surface portions 96t inclined at a predetermined angle with respect to the opening / closing direction of the forming die 90. Are provided symmetrically with respect to the opening and closing direction of the mold 90.

  As shown in FIG. 9A, in the mold 90, the vertical surface portion 92s of the mold surface 92f and the vertical surface portion 96s of the mold surface 96f are provided to face each other with a predetermined distance therebetween, and the inclined surface portion 92t of the mold surface 92f is provided. A molding cavity 79 having a predetermined thickness is formed so as to face the inclined surface portion 96t of the mold surface 96f with a predetermined distance.

  Therefore, the molding cavity thickness in the opening and closing direction of the molding die 90 is formed such that the thickness of the molding cavity 99 formed by the slope portions 92t and 96t is thicker than the thickness of the molding cavity 99 formed by the vertical surface portions 92s and 96s. ing. Further, the pressure attaching portion forming groove portion 92g is formed in a trough portion of a portion that is cut out in a substantially V shape by the mold surface 92f of the fixed die 91, specifically, the two inclined surface portions 92t.

  Also in the mold 90, when the foamable resin 31 is injected into the mold cavity 99, the foamable resin 31 in the mold 92a corresponding to the pressure mounting portion of the fixed mold 91 is cooled by the mold 92a. Then, the pressure mounting portion 103 is formed. As shown in FIG. 9B, by moving the movable die 95 back by a predetermined amount (in the Ya direction in FIG. 9B) and performing the core back, the molding cavity 99 is expanded and the foamable resin 31 is expanded. Foaming is performed, and the foam main body 101 of the workpiece 100 is foam-molded.

  However, a portion of the foam main body 101 that is in a predetermined range continuous to the pressure attachment portion 103, specifically, a portion 104 (pressure attachment portion base) formed by a molding cavity formed by the slope portions 92t and 96t. Since the molding cavity thickness in the opening / closing direction of the molding die 90 before core back is formed thick and the core back amount ratio is set small, the other part of the foam main body 101, specifically, the vertical surface part Foaming is effectively suppressed and molding is performed in a state where the expansion ratio is very low, and the strength and / or rigidity thereof can be increased as compared with the portion molded by the molding cavity formed by 92s and 96s.

  In addition, when molding a foamed resin molded product that is molded so that the pressure mounting portion protrudes integrally from the foam main body portion, a movable core is provided with a slide core portion that is continuous with the pressure mounting portion of the foam main body portion. You may make it form the pressurization attachment part base part which a core back amount rate is set smaller than the other part of a foaming main-body part, and is shape | molded in a part.

  FIG. 10 is a cross-sectional explanatory view showing a fourth modification of the mold used in the molding apparatus, and FIG. 10A shows a state in which a foamable resin is filled in the molding cavity of the mold. FIG. 10B shows a state where the volume of the molding cavity is enlarged and the material resin is foamed. The mold 110 has the same configuration as the mold 20 except that the movable mold 115 is provided with a slide core portion 125 that can move in the opening and closing direction of the mold 110. The reference numerals are attached and the description is omitted.

  In the mold 110, the fixed mold 21 and the movable mold 115 are combined with each other to form a molding cavity 119. The movable mold 115 incorporates a slide core portion 125 that can move in the opening and closing direction of the mold 110. . The slide core portion 125 is formed independently of the movable die 125 by a movable drive mechanism (not shown) that moves the movable die 115 in the opening / closing direction of the molding die 110 (arrows Ya and Yb in FIG. 10). It is possible to move in the opening / closing direction (in the directions of arrows Yc and Yd in FIG. 10).

  As shown in FIG. 10A, the movable mold 115 has the slide core portion 125 positioned in a state of being recessed from the mold surface 116f of the movable mold 115. The movable mold 115 has a mold surface 126f of the slide core portion 126. The pressure attaching portion base groove portion 116g is formed by the sliding contact surface 116s of the movable mold 115 that is in sliding contact with the outer peripheral surface of the slide core portion 126.

  Also in the molding die 110, when the foamable resin 31 is injected into the molding cavity 119, the foamable resin 31 in the molding die portion 22a corresponding to the pressure mounting portion of the fixed die 21 is cooled by the molding die portion 22a. The pressure attaching part 133 is formed. In the mold 110, as shown in FIG. 10 (b), the movable mold 115 is arranged so that the mold surface 116f of the movable mold 115 and the mold surface 126f of the slide core portion 125 are flush with each other (the Ya direction in FIG. And by moving the slide core part 125 backward (in the Yc direction in FIG. 10) to perform the core back, the molding cavity 119 is expanded and the foamable resin 31 is foamed, and the foam main body part 131 of the workpiece 130 is expanded. Is foam-molded.

  However, for a portion 134 (pressure attachment base) that is continuous to the pressure attachment portion 133 in the foam main body 131, the molding cavity thickness before the core back is formed thick and the core back amount rate is set small. Therefore, the foaming is effectively suppressed as compared with the other parts of the foam main body 131, the foaming ratio is very low, and the strength and / or rigidity can be increased.

  In the above embodiment, an air conditioning duct for a vehicle and a model of a simplified model thereof are taken as examples. However, the present invention provides a foamed resin molded product by a foamable resin filled in a mold. The foaming main body part is formed by foaming, and a pressure attaching part composed of a foam suppressing resin part attached to the counterpart member by being pressurized is formed so as to protrude integrally from the foaming main body part. The present invention can also be applied when molding a foamed resin molded product. Thus, it goes without saying that the present invention is not limited to the illustrated embodiments, and various improvements and design changes can be made without departing from the scope of the present invention.

  The present invention relates to a molding method and a molding apparatus for a foamed resin molded product formed from a foamable resin containing a foaming agent in a resin, and is excellent in lightness and heat insulation, for example, an air conditioning duct for a vehicle. It can be suitably applied when molding a foamed resin molded product.

It is sectional explanatory drawing which shows the cross-section of the said air-conditioning duct as a foamed resin molded product which concerns on this embodiment. It is sectional drawing which shows typically the shaping | molding apparatus for carrying out foaming resin shaping | molding of the workpiece | work which concerns on this embodiment. It is an expanded sectional view which expands and shows the principal part of FIG. 2 before a core back. It is an expanded sectional view which expands and shows the principal part of FIG. 2 after a core back. It is sectional drawing which shows typically the vibration welding process to the other member of the said workpiece | work. FIG. 6 is a perspective view showing a molding cavity of a molding die reflecting the shape of the groove portion in order to explain the shape of the pressure attachment portion base forming groove portion. It is sectional explanatory drawing which shows the 1st modification of the shaping | molding die used for the said shaping | molding apparatus. It is sectional explanatory drawing which shows the 2nd modification of the shaping | molding die used for the said shaping | molding apparatus. It is sectional explanatory drawing which shows the 3rd modification of the shaping | molding die used for the said shaping | molding apparatus. It is sectional explanatory drawing which shows the 4th modification of the shaping | molding die used for the said shaping | molding apparatus. It is explanatory drawing which shows typically the state which filled the foaming resin in the shaping | molding cavity, in order to demonstrate the pressure attachment part which concerns on a prior art example, and the foam molding of the periphery. It is explanatory drawing which shows typically the state which expanded the volume of the shaping | molding cavity and foamed material resin, in order to demonstrate the pressure attachment part which concerns on a prior art example, and its periphery foam molding. It is explanatory drawing which shows typically the foamed resin molded product provided with the pressurization attachment part which concerns on a prior art example, and a counterpart member. It is typical explanatory drawing for demonstrating the vibration welding of the foaming resin molded product provided with the pressurization attachment part which concerns on a prior art example, and a counterpart member. It is typical explanatory drawing for demonstrating the favorable vibration welding of the foaming resin molded product provided with the pressurization attachment part, and the other party member.

Explanation of symbols

10, 60, 80, 100, 130 Foamed resin molded article 11, 61, 81, 101, 131 Foam body part 13, 63, 83, 103, 133 Pressure attachment part 14, 64, 84, 104, 134 Foam body part 16 pressure fitting part base 16 mating member 20, 50, 70, 90, 110 Mold 21, 21, 71, 91 Fixed mold 22a, 52a, 72a, 92a Mold 25 corresponding to the pressure fitting part of the mold , 55, 75, 95, 115 Movable mold 29, 59, 79, 99, 119 Molding cavity 30 Injection device 31 Foamable resin D1 Width of pressure mounting portion D2 Width of pressure mounting portion base E Core back amount M Molding device

Claims (10)

The foam body filled in the mold is foam-molded by causing the foam body portion of the foamed resin molded product to core-back the mold body portion corresponding to the foam body portion of the mold and is pressurized. A method for molding a foamed resin molded product, wherein a pressure mounting part composed of a foam suppression resin part attached to a mating member is molded so as to protrude integrally from the foam main body part,
The portion of the foam main body portion that is continuous with the pressure mounting portion is molded with a core back amount rate that is set to be smaller than the other portion of the foam main body portion when the mold portion is core back. A method for forming a foamed resin molded product, comprising forming a pressure attachment base portion.   The method for molding a foamed resin molded product according to claim 1, wherein the pressure attachment base portion is formed wider than the pressure attachment portion.   Prior to the core back, the pressure mounting part is molded by cooling the foamable resin in the molding part corresponding to the pressure mounting part of the mold by the molding part. The method for molding a foamed resin molded product according to claim 1 or 2.   The method for molding a foamed resin molded article according to any one of claims 1 to 3, wherein the foamable resin contains a physical foaming agent.   The method for molding a foamed resin molded article according to claim 4, wherein the physical foaming agent is a fluid in a supercritical state. A mold having a fixed mold and a movable mold which are combined with each other to form a mold cavity, injection means for injecting a foamable resin containing a foaming agent into a resin, and the movable mold into the mold Movable drive means for moving relative to the fixed mold so as to change the volume of the cavity,
The foamable resin is injected into the molding cavity, and the foaming body portion of the foamed resin molded product is cored with the foaming body portion of the movable mold by the foamable resin filled in the molding cavity. Foamed resin molded product, which is molded by foaming by backing up and molding a pressure mounting part composed of a foam suppression resin part attached to a mating member by being pressed so as to protrude integrally from the foaming main body part. The molding apparatus of
The portion of the foam main body portion that is continuous with the pressure mounting portion is molded with a core back amount rate that is set to be smaller than the other portion of the foam main body portion when the mold portion is core back. A molding apparatus for a foamed resin molded product, further comprising a pressure mounting portion base forming means for forming a pressure mounting portion base.   7. The molding apparatus for a foamed resin molded product according to claim 6, wherein the pressure attachment base portion forming means forms a pressure attachment portion base wider than the pressure attachment portion.   Prior to the core back, the pressure mounting portion is molded by cooling the foamable resin in the molding die portion corresponding to the pressure mounting portion of the fixed mold by the molding die portion. An apparatus for molding a foamed resin molded product according to claim 6 or 7.   The apparatus for molding a foamed resin molded article according to any one of claims 6 to 8, wherein the injection means injects a foamable resin containing a physical foaming agent.   The said injection | pouring means inject | pours the foamable resin containing the fluid of a supercritical state as the said physical foaming agent, The molding apparatus of the foamed resin molded product of Claim 9 characterized by the above-mentioned.

Images