Press molding die, press device, method for manufacturing shaped article, and method for manufacturing molded article

Abstract

This press molding die is at least one of a punch and a die, and has a pressing mechanism that supports a workpiece in a position in which the workpiece is not shaped during pressing and that presses the workpiece in a pressing direction.

Description

Press molding die, press equipment, manufacturing method of shaped products, manufacturing method of molded products

[0001] The present disclosure relates to a press molding die, a press device, a method for manufacturing a shaped product, and a method for manufacturing a molded product.

[0002] In recent years, the diversification of customer preferences has led to a growing need for decorative techniques that offer a wide range of design expressions and high-quality design for exterior parts of home appliances, interior parts for automobiles, etc. One such decorative technique is the insert molding method, in which decorative material is positioned and fixed in an injection mold and integrated with the injected resin. This insert molding method can be used to produce molded products using decorative material produced in sheets, such as thinly sliced ​​wood veneer or decorative film printed on a thick substrate.

[0003] On the other hand, when insert molding these decorative materials made in sheets, it is common to need a mechanism to fix the decorative material to the injection molding die, such as drilling positioning holes in the margins around the outer periphery of the product on the decorative material side and providing pins on the injection molding die side to set the positioning holes.

[0004] The insert molding method defined in this disclosure refers to a technique in which the entire exterior surface of a product is formed with decorative material, and depending on the product specifications, may also include a shape in which the decorative material is wrapped around from the exterior surface of the product to the back side of the product.

[0005] Japanese Patent Application Laid-Open No. 2019-181907

[0006] In Figure 6 of Patent Document 1, to obtain a three-dimensional veneer / resin laminated structure housing 40, in Step II, the veneer 1 is placed between a female die 10 and a male die 11 and press-molded to deform the flat veneer 1 into a three-dimensional shape. However, if the side surface does not have a shape without curvature, as shown in Figure 1 of the patent document, deformations such as wrinkles will occur in the veneer 1 in Step II, making it impossible to obtain a veneer / resin laminated structure housing 40 with a beautiful appearance. In other words, certain restrictions on the shape are an issue. Wrinkles that occur in the press process will remain in the injection molding process, making it impossible to obtain a beautiful appearance.

[0007] An object of the present disclosure is to provide a press molding die that is less likely to cause wrinkles.

[0008] The press molding die according to the present disclosure is a press molding die that is at least one of a punch and a die, and has a support and pressing mechanism that supports the workpiece at a position where the workpiece is not shaped during press processing and presses the workpiece along the pressure direction.

[0009] According to the press molding die of the present disclosure, the laminate is placed between the side pad and the punch die during the press process, and is restrained until the bottom dead center, thereby preventing wrinkles during the press process. This makes it possible to provide a decorated part using a laminate that has wider shape constraints without generating wrinkles, compared to conventional examples.

[0010] 2. FIG. 1 is a schematic cross-sectional view showing the cross-sectional structure of a decorated part that is a molded part according to embodiment 1. FIG. 2 is a perspective view showing an image obtained by analyzing the appearance of an intermediate part and a shaped part obtained in each step of a method for manufacturing a shaped part. FIG. 3 is a schematic cross-sectional view showing a thermocompression bonding step for obtaining a laminate that is a part of the decorated part of FIG. 1. FIG. 4 is a plan view (a) and a cross-sectional view (b) illustrating a trimming process step of a laminate. FIG. 4 is a schematic cross-sectional view showing each step of a method for manufacturing a shaped part using a press-molding die according to embodiment 1. FIG. 5 is a diagram showing a front view, a back view, and multiple side views of a laminate of shaped parts. FIG. 5 is a plan view showing a front view of a press-molding die including a die, side pads, and a side pad drive mechanism in the method for manufacturing the shaped part of FIG. 2. FIG. 6 is a schematic cross-sectional view showing a method for driving side pads using springs in a press-molding die according to embodiment 1. FIG. 7 is a schematic cross-sectional view showing a method for driving side pads using springs in a press-molding die according to embodiment 1. FIG. 8 is a schematic cross-sectional view showing a method for driving side pads using springs in a press-molding die according to embodiment 1. FIG. 1 is a schematic cross-sectional view showing a method for driving a side pad using a spring and a cylinder in a press molding die according to embodiment 1. FIG. 2 is a schematic cross-sectional view showing a method for driving a side pad using a spring and a cylinder in a press molding die according to embodiment 1. FIG. 3 is a schematic cross-sectional view showing the shape and position of a side pad in a press molding die according to a modified example of embodiment 1. FIG. 4 is a schematic cross-sectional view showing the shape and position of a side pad in a press molding die according to a modified example of embodiment 1. FIG. 5 is a schematic cross-sectional view showing the shape and position of a side pad in a press molding die according to a modified example of embodiment 1. FIG. 6 is a schematic cross-sectional view showing the shape and position of a side pad in a press molding die according to a modified example of embodiment 1. FIG. 7 is a schematic cross-sectional view showing the cross-sectional structure of a step of placing a laminate, which is a shaped product, in a cavity die for insert molding, which is an example of a method for producing a molded product according to embodiment 1. FIG. 8 is a schematic cross-sectional view showing the cross-sectional structure of a step of injecting an injection molding resin into a cavity defined between a core die and a back surface of the laminate placed in the cavity die for insert molding, which is an example of a method for producing a molded product according to embodiment 1.1 is a schematic cross-sectional view showing a primary appearance surface and a secondary appearance surface, which are normal appearance surfaces, of a decorated part that is a molded product according to embodiment 2. FIG. 1 is a schematic cross-sectional view showing each step of a method for manufacturing a shaped product using a press-molding die according to embodiment 2. FIG. 2 is a schematic cross-sectional view showing a cross-sectional structure of a step of placing a laminate that is a shaped product in a cavity die for insert molding, which is an example of a method for manufacturing a molded product according to embodiment 2. FIG. 3 is a schematic cross-sectional view showing a cross-sectional structure of a step of injecting an injection molding resin into a cavity defined between a core die and the back surface of a laminate placed in a cavity die for insert molding, which is an example of a method for manufacturing a molded product according to embodiment 1. FIG. 4 is a schematic cross-sectional view showing a cross-sectional structure of a molded product according to embodiment 2. FIG. 5 is a schematic cross-sectional view showing a method of driving side pads of a press-molding die according to embodiment 2. FIG. 6 is a schematic cross-sectional view showing a method of driving side pads of a press-molding die according to embodiment 2. 10A and 10B are schematic cross-sectional views showing a method for driving side pads of a press-molding die according to Embodiment 2. FIG. 10B are schematic cross-sectional views showing a method for driving side pads of a press-molding die according to Embodiment 2.

[0011] The press molding die according to the first aspect is a press molding die which is at least one of a punch and a die, and has a support and pressing mechanism which supports the workpiece at a position where the workpiece is not shaped during press processing and presses the workpiece along the pressure direction.

[0012] The press molding die according to the second aspect may further include a side pressing mechanism which, in the first aspect described above, supports the workpiece from a direction perpendicular to the pressure direction during press processing as the workpiece deforms, and which retracts to a surface of the press mold that is continuous with the surface that contacts the workpiece as shaping progresses, thereby shaping the workpiece.

[0013] The press-molding die according to a third aspect may be the die according to the first or second aspect, and may have a plurality of pressing mechanisms.

[0014] A press-molding die according to a fourth aspect is the die of the first or second aspect, wherein the pressing mechanism may have an undercut forming function of forming an undercut in the workpiece.

[0015] A press-molding die set having a punch and a die according to a fifth aspect includes the press-molding die according to the first or second aspect.

[0016] A press apparatus according to a sixth aspect includes the press-molding die set according to the fifth aspect.

[0017] The method for manufacturing a shaped product according to the seventh aspect includes a first step of placing the object to be processed on a press molding die, and a second step of pressurizing the object to be processed in the press molding die to form the object into a shaped product, in which the object to be processed is supported at a position where it will not be shaped, and is pressed along the pressure direction while being pressurized to form the object into a shaped product.

[0018] The method for manufacturing a shaped product according to the eighth aspect is the same as the seventh aspect, and in the second step, the object to be processed may be supported from a direction perpendicular to the pressure direction as the object to be processed deforms, and the object to be processed may be shaped along a surface continuous with the surface of the press mold that contacts the object to be processed in response to the progress of shaping.

[0019] The method for producing a shaped product according to a ninth aspect may be the same as the seventh or eighth aspect, and further include an undercut forming step of forming an undercut in the object to be processed.

[0020] The method for manufacturing a molded product according to the tenth aspect includes the steps of placing the shaped product obtained by the method for manufacturing a shaped product according to the seventh or eighth aspect in the cavity mold of an injection molding die consisting of a cavity mold and a core mold, and clamping the cavity mold and the core mold together, pouring resin into the cavity defined between the shaped product placed in the cavity mold and the core mold, and, after the resin has hardened, opening the cavity mold and the core mold and removing a molded product made of the shaped product and the hardened resin.

[0021] Hereinafter, a press-molding die according to each embodiment of the present disclosure and a method for manufacturing a molded product using the die will be described with reference to the drawings.

[0022] (Embodiment 1) <Method for Manufacturing Molded Product> FIG. 1 is a schematic cross-sectional view showing the cross-sectional structure of a decorative part 6, which is a molded product obtained in this embodiment 1. As shown in FIG.

[0023] As shown in FIG. 1, a decorated part 6 which is a molded product is made up of a base resin 5 and a laminate 7 , and the laminate 7 is further made up of a decorative layer 2 , an adhesive layer 3 and a support layer 4 .

[0024] <Decorative Layer> The decorative layer 2 is not limited as long as it is made of a commonly used decorative material such as fabric, natural wood, leather, or decorative film.

[0025] The thickness of the decorative layer 1 is not particularly limited depending on the characteristics of the decorative material, but is preferably in the range of 0.1 mm to 3 mm. If the thickness of the decorative layer 1 is less than 0.1 mm, handling becomes difficult, and defects such as wrinkles and tears tend to occur during processing. On the other hand, if the thickness of the decorative layer 2 is greater than 3 mm, the hardness of the entire laminate increases, which deteriorates its flexibility and its ability to conform to the product shape.

[0026] <Adhesive Layer> The adhesive layer 3 serves to bond the decorative layer 2 and the support layer 4. The adhesive layer 3 is made of, for example, a vinyl chloride-vinyl acetate copolymer, an olefin-based, polyolefin-based, urethane-based, acrylic-based or other resin, and is formed in a form that completely covers the surface of the support layer 4. There are no limitations on the material as long as it is possible to bond the decorative layer 2 and the support layer 4 to each other.

[0027] Furthermore, the average film thickness of the adhesive layer 3 is preferably 2 μm or more and 200 μm or less. If the thickness is less than 2 μm, the adhesive layer 3 itself may lack sufficient film strength, resulting in peeling defects such as cohesive failure. Furthermore, the adhesive thickness is insufficient, and sufficient adhesive strength to the decorative layer 2 and the support layer 4 cannot be obtained. On the other hand, if the thickness is greater than 200 μm, the adhesive strength is not affected, and the increased film thickness increases manufacturing costs. Considering the balance between film strength, adhesive strength, and manufacturing costs, a film thickness of 3 μm or more and 100 μm or less is more preferable. Furthermore, the penetration film thickness (due to the anchor effect) of the adhesive layer 3 into the support layer 4 is preferably 5 μm or more. If the thickness is less than 5 μm, the adhesive strength to the support layer 3 may be insufficient, resulting in interfacial peeling defects. The process for forming the adhesive layer 3 is not limited, depending on the handling method.

[0028] When the adhesive layer 3 is handled in a liquid state, it may be formed in advance on the decorative layer 2 side or on the support layer 4 side using a known printing or coating process such as spray atomization, roll coating, or inkjet coating. Alternatively, when the adhesive layer 3 is handled in a solid state such as a sheet, it may be bonded to the decorative layer 2 first and then to the support layer 3. Alternatively, conversely, it may be bonded to the support layer 4 first and then to the decorative layer 2. Furthermore, the decorative layer 2, adhesive layer 3, and support layer 4 may be bonded simultaneously. By forming the adhesive layer 3 in a form that completely covers the surface of the support layer 4, it is possible to improve its conformability to the support layer 4.

[0029] <Support Layer> The support layer 4 improves the strength of the laminate 7 itself through hot press processing and plays a role in maintaining the predetermined processed shape of the laminate 7. The adhesive layer 3 is formed in a form that completely covers the support layer 4, and the decorative layer 2 is formed via the adhesive layer 3. Therefore, the improvement in the strength of the support layer 3 itself effectively improves the strength and shape retention of the laminate 7 itself.

[0030] The material, thickness, etc. of the support layer 4 can be selected depending on the application. The support layer 4 is formed, for example, by forming a web by folding fibers spun from a carding machine diagonally across each other, and then entangling the fibers using a needle punch machine to form a nonwoven fabric sheet. Materials that can be selected include, for example, polyester, polyethylene terephthalate, polypropylene, rayon, nylon, and vinylon. The support layer 4 may be formed from two or more materials with different melting points or from similar materials with different melting points. For example, if polyethylene terephthalate fibers coated with polyethylene having a lower melting point than polyethylene terephthalate are used, the polyethylene terephthalate fibers within the nonwoven fabric sheet can be impregnated with polyethylene by optional heat treatment after the nonwoven fabric sheet is formed, resulting in a support layer 4 with high strength.

[0031] <Overview of the manufacturing method of a shaped product> Figures 2(a) to 2(d) are perspective views of images of the appearance of intermediate parts and shaped products obtained in each step of the manufacturing method of a shaped product, obtained by analysis. Figure 2(a) is a perspective view showing a planar laminate obtained by a thermocompression bonding step and then processed into the shape of a decorated part in a trimming step. Figure 2(b) is a perspective view showing an intermediate part of a shaped product in a shaping (preforming) step in which the laminate is pressurized using a press mold according to embodiment 1. Figure 2(c) is a perspective view showing a shaped product in the shape of a decorated part after pressurization, following Figure 2(b). In the shaping (preforming) step using the press mold according to embodiment 1, the laminate is supported at a position where it is not shaped, and the laminate is pressed along the pressure direction, so wrinkles are less likely to occur in the shaped product.

[0032] On the other hand, Fig. 2(d) is a perspective view of a shaped product obtained using a conventional press molding die. As shown in Fig. 2(d), in the shaped product obtained using a conventional press molding die, wrinkles occur on the surface of the laminate. This is thought to be because the edges are not pressed when the laminate is pressurized, and as the laminate is pressurized, excess surface of the laminate shaped into the shape of the decorative part is left over, causing wrinkles.

[0033] Thereafter, in an injection molding process (not shown), a base resin is applied to the laminate in the shape of the decorated part obtained in the shaping (preform) process to obtain the decorated part. These processes will be explained below.

[0034] 3 is a schematic cross-sectional view showing the thermocompression bonding step for obtaining the laminate 7. The laminate 7 is formed by compression bonding using a thermocompression bonding device P that can apply heat and pressure. By applying heat and pressure, the adhesive layer 3 disposed between the decorative layer 2 and the support layer 4 melts, and the decorative layer 2 and the support layer 4 are tightly adhered to each other, thereby obtaining the laminate 7.

[0035] Examples of the thermocompression bonding device P include known devices such as a general-purpose press that applies pressure with upper and lower heated plates, a multi-stage press, a vacuum laminator, and a roll-to-roll press. The laminate 7 manufactured using these devices has a firmer sheet state than the decorative layer 2 alone, which improves handling during subsequent processing. If the support layer 4 is composed of two types of fibers, the temperature of the thermocompression bonding device can be adjusted to melt one fiber and impregnate the other fiber, thereby increasing the strength of the laminate 7.

[0036] 4A and 4B are a plan view and a cross-sectional view illustrating a trimming process for processing the laminate 7 into a two-dimensional shape that takes into account the unevenness and bending of the product shape. Trimming methods include, for example, shape punching using a Thomson die, laser cutting, and hand cutting, but are not particularly limited as long as they can be trimmed to the desired product shape. In subsequent steps, the laminate is processed into a three-dimensional shape that matches the product shape. Therefore, if the laminate can be trimmed so that there is no excess material in the product shape, subsequent post-processing will be unnecessary, improving productivity.

[0037] <Press-molding die> Fig. 5 is a schematic cross-sectional view showing each step of a method for manufacturing a shaped product using a press-molding die according to embodiment 1. The press-molding die according to embodiment 1 will be described with reference to Fig. 5. For convenience, the vertically upward direction is defined as the Z direction, and the horizontal direction perpendicular to this is defined as the X direction from left to right on the paper, and the front to back on the paper is defined as the Y direction.

[0038] The press mold according to the first embodiment is at least one of a punch 12 and a die 14. In FIG. 5 , this corresponds to the die 14. This press mold (die 14) includes a stripper 13 and a stripper drive mechanism 9 (support and pressing mechanism) that support the laminate (workpiece) 7 at a position where the laminate 7 is not shaped during press working and presses the laminate 7 along the pressure direction (vertical direction: Z direction). The press mold also includes side pads 17 and a side pad mechanism 18 (side pressing mechanism) that support the laminate 7 in a direction perpendicular to the pressure direction (horizontal direction: X direction) as the laminate 7 deforms during press working. As described above, the stripper 13 and the stripper drive mechanism 9 constitute a support and pressing mechanism. The side pads 17 and the side pad mechanism 18 constitute a side pressing mechanism.

[0039] Below, we will explain the functions of the support and pressure mechanism constituted by the stripper 13 and the stripper drive mechanism 9, and the side pressure mechanism constituted by the side pad 17 and the side pad drive mechanism 18, which are features of the press molding die according to embodiment 1.

[0040] 5(a) is a schematic cross-sectional view showing the initial state of the forming (preforming) process. The press molding die is composed of a movable punch die 12, a stripper 13, a stripper drive mechanism 9, a die 14, a pad 15 installed on the die 14, a pad drive mechanism 16, a side pad 17, and a side pad drive mechanism 18.

[0041] The stack 7 is supported vertically from below by the pads 15 and the pad drive mechanism 16 .

[0042] The stripper drive mechanism 9, pad drive mechanism 16, and side pad drive mechanism 18 are installed to support, press, and restrain the laminate 7 as the punch 12 operates. The stripper drive mechanism 9, pad drive mechanism 16, and side pad drive mechanism 18 are fabricated using known drive methods, such as metal springs, gas springs, hydraulic or pneumatic pumps, and are selected depending on the preforming process, such as the required pressure, cost, and control method. These drive mechanisms 9, 16, and 18 each drive the stripper 13, pad 15, and side pad 17, respectively. These drive methods include known drive methods, such as metal springs, gas springs, hydraulic or pneumatic pumps, and are selected depending on the preforming process, such as the required pressure, cost, and control method. A protrusion allowance 19, which is the length of the side pad 17 protruding from the surface of the die 14, defines the step between the die 14 and the side pad 17. The top surface of the side pad 17 is flush with the top surface of the die 14.

[0043] 5(b), the punch die 12, the stripper 13, and the stripper drive mechanism 9 are movable, and the stripper 13 supports the laminate 7 in the pressure direction (Z direction), and the stripper 13 and the side pad 17 press the laminate 7 in the pressure direction (Z direction). In other words, the laminate 7 is restrained between the stripper 13 and the upper surface of the side pad 17, and a laminate restraint point A20 is generated.

[0044] Although the laminate restraint point A20 presses and restrains the laminate 7 between the stripper 13 and the side pad 17, it does not completely fix the laminate 7. For example, the laminate 7 may be easily movable by a force applied in an in-plane direction perpendicular to the pressing direction. The same applies to the laminate restraint points B and C that appear later.

[0045] In Figure 5(c), the punch die 12 further descends, the stripper 13 and the stripper drive mechanism 9 move, and the punch die 12 and the pad 15 support the stack 7 in the vertical direction (Z direction) and create a stack restraint point B21 that presses the stack 7.

[0046] 5( d ), a laminate restraint point C22 is generated between the punch 12 and the side pad 17, supporting and pressing the vicinity of the end face of the laminate 7. The punch 12, the stripper 13, and the stripper drive mechanism 9 are further moved, and the laminate 7 is deformed from a two-dimensional shape to a three-dimensional shape by the punch 12. At this time, the movement of the punch 12 presses the side pad 17 through the laminate 7, causing it to retreat in the horizontal direction (X direction). At this time, the laminate 7 is restrained by the punch 12 and the side pad 17 with a forward force applied by the side pad drive mechanism 18.

[0047] In FIG. 5( e), the laminate restraint point A20 by the stripper 13 and stripper drive mechanism 9 is eliminated. This is because, as the punch 12 moves vertically downward (in the −Z direction), the end face of the laminate 7 separates from the upper surface of the side pad 17 and is drawn into the gap between the punch 12 and the die 14. In the press-forming die according to embodiment 1, side pads 17 and a side pad drive mechanism 18 are disposed as shown in FIG. 5( e). This allows a laminate restraint point B22 that supports and presses the laminate 7 in the horizontal direction to be provided at a location continuous from the end face of the laminate. In other words, the laminate restraint point A20 by the stripper 13 and stripper drive mechanism 9 and the laminate restraint point B22 by the side pads 17 and side pad drive mechanism 18 can be provided continuously. As a result, even if the end face of the laminate 7 separates from the top surface of the side pad 17, the laminate restraint point B22 provided by the side pad 17 and the side pad drive mechanism 18 can continuously support and press the vicinity of the end face of the laminate 7, thereby preventing excess laminate 7 from wrinkling.

[0048] The constraint of the laminate 7 by the stripper 13 and the stripper drive mechanism 9, and the constraint of the laminate 7 by the side pads 17 and the side pad drive mechanism 18, need only be light enough to allow the laminate 7 to slide. For example, if the decorative layer of the laminate is made of cloth with a thickness of about 0.4 mm, the constraint force per side pad and per side of the slipper may be less than 20 kg. Furthermore, if the decorative layer of the laminate is made of leather, the constraint force may be about 50 kg.

[0049] FIG. 5(f) shows the state when the punch 12 is lowered to the bottom dead center. This causes the laminate 7 to be shaped into a shaped product. At this time, the projection allowance 19 of the side pads 17 from the die 14 is set to zero when the punch 12 reaches the bottom dead center. This means that the side pads 17 are designed to be aligned with the surface of the die 14 and positioned to correspond to the product shape. Therefore, the provision of the side pads 17 does not affect the product shape of the shaped product. At the time shown in FIG. 5(f), the laminate 7 is not on the upper surface of the die 14. At this time, the edge of the laminate 7 is within the range of the inside of the side pads 17 (the laminate restraint area B22).

[0050] Figures 5(g) and 5(h) show two patterns for removing the laminate 7 after the preforming process. In Figure 5(g), the side pads 17 and side pad drive mechanisms 18 are in a state where the projection allowance 19 of the side pads 17 from the die 14 is zero, i.e., the side pads are in the product shape position, which is convenient for removing the shaped laminate 7 until removal in Figure 5(f). However, if the drive mechanism 18 for the side pads 17 is a spring, it is necessary to add a mechanism that maintains the projection allowance 19 of the side pads 17 from the die 14 at zero and allows them to move forward again in the next process shown in Figure 5(a), which makes the mold more complex. In the case of hydraulic or pneumatic pressure, the position of the side pads 17 can be adjusted by damping the pressure, but a control or valve for damping is required.

[0051] Figure 5(h) is a schematic cross-sectional view showing a case where the side pad 17 returns to the same position as in Figure 5(a) as the punch 12 is driven. This method does not require a mechanical structure, control, or valve, making the die less complex than Figure 5(g), but it is disadvantageous for removing the laminate 7. Furthermore, because the laminate 7 is restrained from the sides by the side pad 17 and the punch 12 before the punch 12 returns to the same position as Figure 5(a), the formed shape of the laminate 7 may deviate from the product shape shown in Figure 5(f). However, because the risk of deformation of the formed shape depends on the relationship between the product shape and the amount of the side pad's projection allowance 19 from the die, both Figure 5(g) and Figure 5(h) can be used on a case-by-case basis.

[0052] FIG. 6 illustrates an example of the shape of a shaped product obtained using the press-molding die according to the first embodiment. FIG. 6 shows a front view, a back view, and multiple side views of a laminate 7 of a shaped product. This shape is a convex shape with a 3D curved surface, with front view 1 being the front view of the product. In front view 2, four curves A, B, C, and D are shown from the top of the figure of this product for explanation. Curves A and B are shown in side view 2, curve C is the upper edge of the convex shape of the product, and curve D is the lower edge of the convex shape of the product. Curves C and D are shown in side view 1, with curve C being the upper edge of the convex shape of the product and curve D being the lower edge of the convex shape of the product.

[0053] When curves A, B, C, and D form an arc extending from the edge of the product toward the center, the laminate at both ends of the product's length deforms into a 3D shape as it moves toward the center of the product, moving from Figure 5(d) to Figure 5(f). This movement toward the center of the product causes wrinkles. The wrinkles are larger on the side of curves C and D than on the side of curves A and B. This is because curves C and D have a smaller curvature than curves A and B. In this first embodiment, this movement is regulated by side pads 17 and side pad drive mechanism 18.

[0054] The phenomenon of wrinkles will be explained using Figure 2. Figures 2(a) to 2(d) are perspective images of the appearances of the intermediate parts and shaped products obtained in each step of the manufacturing method of the shaped product as described above, which have been analyzed.

[0055] FIG. 2(a) shows the laminate 7 at the time of FIG. 5(c), which has a 2D shape. FIG. 2(b) shows the laminate 7 at the time of FIG. 5(d), which has been deformed into a 3D shape by the punch die 12. FIG. 2(c) shows the laminate 7 at the time of FIG. 5(e). FIG. 2(d) is a perspective view showing the results of an analysis performed using a press-molding die other than that of the first embodiment, but with the side pad projection 19 from the die intentionally fixed at zero from FIG. 5(a) to FIG. 5(e). In other words, this is the result of an analysis performed without restricting the movement of the laminate toward the center of the product by the side pad 17 and side pad drive mechanism 18. As shown in FIG. 2(d), wrinkles toward the center can be visualized, confirming the effectiveness of the analysis.

[0056] <Press-molding mold> FIG. 7 is a plan view showing a front view of a press-molding mold including a die 14, side pads 17, and a side pad drive mechanism 18 used in the manufacturing method of the shaped product shown in FIG. 2. Note that the same components as those in FIG. 5 are designated by the same reference numerals and will not be described again. The arrangement of the side pads is designed taking into consideration the length and curvature of the product, as well as the flexibility of the laminate 7. For example, as shown in FIG. 7, one side pad 17 is arranged on each side of the upper product curvature. On the other hand, the lower product in FIG. 7 has a smaller curvature than the upper side and is longer than the upper edge, so three side pads A23, B24, and C25 are arranged instead of one side pad. In this way, the side pads may be divided into two or more parts. By dividing the side pads as shown in FIG. 7, the restraining forces of the side pad drive mechanisms A26, B27, and C28 can be independent, making adjustment easier. In other words, with one side pad, there is essentially only one point of contact with the laminate, making it difficult to achieve uniform restraint over a long curve.By dividing the pad into multiple side pads, restraint can be achieved at multiple points, stabilizing the restraint and further reducing the occurrence of wrinkles.

[0057] <Side Pad Drive Mechanism> The side pad drive mechanism will be described using Figures 8-1 to 8-3 and 9-1 to 9-3. Note that in Figures 8-1 to 8-3 and 9-1 to 9-3, the outlines of each component are shown linearly for convenience, but this does not mean that the outer shape of each component is linear or flat. Each component may also have a curved or curved surface.

[0058] Figures 8-1 to 8-3 illustrate a method for driving the side pads using springs. Note that the same reference numerals are used for the same components as in Figure 5, and their explanations are omitted. (1) Figure 8-1 is a detailed illustration of a portion of Figure 5(a). A metal spring or a gas spring may be used as the spring 30, a specific example of the side pad driving mechanism 18. The backing plate 29 of the side pad driving mechanism functions to secure the die 14 and the spring 30. (2) Figure 8-2 is a detailed illustration of a portion of Figure 5(e). As the punch 12 moves, the side pad 17 retreats, and the projection 19 of the side pad 17 from the die 14 decreases compared to Figure 8-1. The punch 12 descends to the bottom dead center while the reaction force of the spring 30, i.e., the forward force of the side pad 17, restrains the laminate 7. (3) Figure 8-3 is a detailed illustration of a portion of Figure 5(h). 8-1, the projection allowance 19 of the side pad 17 from the die 14 becomes the same as that in FIG. 8-1. The forward force of the side pad 18 can be adjusted by changing the spring constant of the spring 30.

[0059] Figures 9-1 to 9-3 illustrate a method for driving the side pads using a spring and a cylinder. Note that the same reference numerals are used for the same components as those in Figure 5, and their descriptions are omitted. (1) Figure 9-1 is a detailed explanation of a portion of Figure 5(a). The cylinder 31, a specific example of the side pad driving mechanism 18, may be a hydraulic cylinder or an air cylinder using gas. The support plate 29 of the side pad driving mechanism functions to secure the die 14, spring 30, and cylinder 31. Note that in Figure 9-1, the cylinder 31 advances in the ON state, and its driving force and the spring's restoring force are set to be opposite, i.e., in opposite directions. The length of the projection 19 of the side pad 17 from the die 14 can be adjusted using the spring 30 and cylinder 31. (2) Figure 9-2 is a detailed explanation of a portion of Figure 5(e). As the punch 12 descends, the side pads 17 retreat, reducing the projection allowance 19 of the side pads 17 from the die 14 compared to FIG. 9-1. The punch 12 descends to bottom dead center while restraining the laminate 7 with the forward force of the cylinder. (3) FIG. 9-3 is a detailed illustration of a portion of FIG. 5(g). By turning off the cylinder 31 when the punch 12 reaches bottom dead center, the reaction force of the spring 30 causes the projection allowance 19 of the side pads 17 from the die 14 to become shorter than in the state shown in FIG. 9-1, making it easier to remove the preformed laminate 7. The advantage of using the spring 30 and the cylinder 31 to drive the side pad 17 is that the restraining force on the laminate 7 can be adjusted by adjusting the forward force at any timing when the punch 12 descends toward bottom dead center in FIG. 9-2. On the other hand, there is a disadvantage that the timing control of the forward force of the cylinder is required, and it becomes more expensive than configuring the side pad drive mechanism 18 using only the spring 30 of Figures 8-1 to 8-3.

[0060] <Shape and Position of Side Pads> Figures 10-1 to 10-4 are schematic cross-sectional views showing the shape and position of side pads in a press-molding die according to a modification of the first embodiment. Note that components identical to those shown in Figure 5 are designated by the same reference numerals and will not be described again. Also, while the outlines of each component are depicted linearly in Figures 10-1 to 10-4 for convenience, this does not mean that the external shapes of each component are linear or planar. Each component may also have a curved or curved surface. (1) As shown in Figure 10-1, the side pads may be multi-tiered in the vertical direction (thickness direction), such as side pad 17 and the side pad D32 contained therein. This multi-tiered design allows the side pad 17 to restrain the laminate 7 overall while locally increasing the restraining force of the laminate 7. (2) The side pad 17 may be included within the die 14, as shown in Figure 10-2. By incorporating the side pads 17 into the die 14, the thickness of the die 14 can be reduced, improving handling when replacing the die 14. (3) Figure 10-3 explains the shape of the side pads 17. Figure 10-3 is a schematic cross-sectional view of the die 14. As the punch 12 descends, the laminate 7 is pulled in the direction of the arrow, so it is preferable that the corners of the side pads 17 have a radius of 2 mm or more, as shown in Figure 10-3. (4) Figure 10-4 is a view of the side pads 27 and D32 as seen from the driving direction. As shown in Figure 10-4, the side pads 17 may also have a rectangular shape with corners of radius 2 mm or more, or a cylindrical side pad E33 with a tip of radius 2 mm or more may also be used.

[0061] <Insert Molding> Figures 11-1 and 11-2 are schematic cross-sectional views showing the cross-sectional structure at each step of insert molding, which is an example of a manufacturing method for a molded product according to the first embodiment. Insert molding is performed as follows: (1) The preformed laminate 7 described above is placed between a cavity mold 34 and a core mold 35, which are injection molding dies (Figure 11-1). (2) The cavity mold 34 and the core mold 35 are clamped together. (3) An injection molding resin 8 is injected into the cavity defined between the back surface of the laminate 7 placed on the cavity mold 34 and the core mold 35 (Figure 11-2). (4) After the injection molding resin 8 has hardened, the cavity mold and the core mold are opened, and a molded product made of the shaped product and the hardened resin is removed.

[0062] Through the above steps, a decorated part, which is a molded product, can be obtained.

[0063] (Embodiment 2) In comparison with embodiment 1, embodiment 2 differs in that the laminate 7 is disposed up to a portion of the rear surface of the decorative part. Fig. 12 is a schematic cross-sectional view showing the primary appearance surface and the secondary appearance surface, which are the normal appearance surfaces of the decorative part, which is a molded product according to embodiment 2. Note that the same reference numerals are used for the same parts as in Fig. 1, and the description thereof will be omitted.

[0064] As shown in Figure 12, the decorative part 6 has an exterior surface (primary exterior surface) 41 and a secondary exterior surface 42, with the secondary exterior surface being the surface that is invisible unless one looks closely. Generally, if the injection-molded resin 8 constituting the back surface of the decorative part is visible, even at the secondary exterior surface 42, it will give the impression of lowering the sense of luxury and quality. For this reason, the laminate 7 often needs to cover the secondary exterior surface 42. The secondary exterior surface often corresponds to an undercut portion in the mold, and this undercut must be created during the molding (preforming) process. On the other hand, if this undercut is present, a movable structure called a slide must be configured within the mold to release the molded laminate 7 from the mold.

[0065] Figure 13 is a schematic cross-sectional view showing each step of a method for manufacturing a shaped product using a press-molding die according to embodiment 2. A configuration for using the side pads as slides will be described using Figure 13. The same components as those in Figure 5 are designated by the same reference numerals, and their description will be omitted. The press-molding die according to embodiment 2 differs from embodiment 1 in that it includes a punch die-side undercut treatment 36, a laminate undercut 37, an air supply path 38 (sometimes referred to as a gas supply path 38), and a compressed air supplier 39.

[0066] As shown in FIG. 13( a), the press-forming die according to the second embodiment is provided with a punch die side undercut 36 in the punch die 12, an air supply path 38 for releasing the laminate 7 from the punch die 12, and a compressed air supplier 39 for supplying air through the air supply path 38. The punch die side undercut 36 is a recessed shape provided in the punch die 12. Since the punch die side undercut 36 is designed to accommodate the side pads 17 and the laminate 7, the recessed shape is designed to be at least 0.2 mm larger than the thickness of the side pads 17 and the laminate 7, and the recessed depth is designed to be at least 0.5 mm deeper than when the side pads 17 are at their most advanced positions. The air supply path 38 may be used to supply a gas other than air for releasing the laminate 7 from the punch die 12. Examples of gases other than air include carbon dioxide, argon, oxygen, and nitrogen.

[0067] 13(a) to 13(e) are performed in the same order as in FIGS. 5(a) to 5(e), and therefore a description thereof will be omitted.

[0068] 13(f), laminate undercut 37 is formed. When punch 12 reaches bottom dead center, side pad 17 advances toward the space of punch-side undercut treatment 36. During this advance, laminate 7 is restrained by laminate restraint location B21, while laminate 7 in contact with side pad 17 is pulled into punch-side undercut treatment 36 as the side pad advances, so that laminate undercut 37 is formed.

[0069] In Figure 13(g), the side pad 17 has been retracted by the side pad drive mechanism 18 to a position where it does not prevent the punch 12 from being released from the die 14. At this time, the laminate 7 is prevented from being released from the punch 12 by the laminate undercut 37. Therefore, the release of the laminate 7 is promoted by flowing air from a compressed air supplier 39 through an air supply path 38, resulting in the laminate 7 having the laminate undercut 37 shown in Figure 13(h). Using this laminate 7, an injection molding process as shown in Figures 14-1 to 14-3 can be performed to obtain a decorated part 6, which is a molded product in which the laminate 7 is present not only on the exterior surface (primary exterior surface) 41 but also on the secondary exterior surface 42, as shown in Figure 14-3. In Figures 14-1 to 14-3, the same components as those in Figures 12 and 13 are designated by the same reference numerals, and their description will be omitted.

[0070] <Side Pad Drive Mechanism> Next, the drive mechanism of the side pad 17 in the press molding die according to the second embodiment will be described with reference to Figures 15-1 to 15-7. The same components as those in Figures 9-1 to 9-3 are designated by the same reference numerals, and their description will be omitted. Note that, for convenience, the outlines of each component are shown linearly in Figures 15-1 to 15-7, but this does not mean that the external shapes of each component are linear or planar. Each component may also have a curved or curved surface.

[0071] Fig. 15-1 is a detailed explanation of a part of Fig. 13(a). The punch 12 is provided with a punch-side undercut 36, an air supply path 38, and a compressed air supply device 39.

[0072] Figure 15-2 is a detailed explanation of a part of Figure 13(b). As the punch 12 descends, the side pad 17 is pressed down, but the laminate 7 is deformed by the reaction force of the cylinder 31, while being restrained by a restraining force corresponding to the reaction force of the cylinder. In addition, the laminate 7 is restrained by a certain restraining force by being set between the stripper 13 and the side pad 17.

[0073] Figure 15-3 is a detailed explanation of a portion of Figure 13(e). As the punch 12 further descends, the laminate 7 moves to a location away from the stripper 13. At this time, the laminate 7 is deformed while being restrained by a horizontal restraining force between the side pad 7 and the punch 12 in accordance with the forward force of the cylinder 31. Note that in this case, as in the first embodiment, the laminate 7 continues to be supported, pressed, and restrained between the side pad 7 and the punch 12 even after the end face of the laminate has been released from the stripper 13.

[0074] Fig. 15-4 is a detailed explanation of part of Fig. 13(f). At this time, the punch 12 has descended to the bottom dead center position, and by adjusting the forward position of the cylinder so that the side pad 17 is stored in the punch-side undercut processing 36 provided on the punch 12 in the height direction, it is possible to form the laminate undercut 37.

[0075] FIG. 15-5 is a detailed explanation of FIG. 13(g). With the punch 12 at the bottom dead center, the side pad 17 is retracted. Then, air is supplied from a compressed air supplier 39 through an air supply path 38 so that the laminate undercut 37 can be smoothly released from the punch 12. Multiple air supply paths 38 may be installed. For example, by installing an air supply path 38 at a location in contact with the laminate undercut 37 within the punch-side undercut treatment 36, the laminate undercut 37 can be easily released from the punch 12. The air supply path 38 may be tubular or slit-shaped.

[0076] 15-6 is a detailed explanation of FIG. 13(h). The side pads 17 are retracted to a position where they do not interfere with the descent of the punch 12.

[0077] 15-7 is an enlarged view of the side pad 17 and the punch die side undercut treatment 36. To ensure smooth driving, a corner R43 of 0.5 mm or more may be provided. However, if the punch die side undercut treatment 36 is provided with a corner R43 of 0.5 mm or more, the laminate undercut will also have the same R, so the radius of the punch die side undercut treatment 36 may be intentionally set to less than 0.5 mm.

[0078] In the second embodiment, FIGS. 15-1 to 15-7 show an example of a driving method for a side pad for forming a laminate undercut, and a plurality of side pads may be provided on the die as shown in FIGS. 9-1 to 9-3.

[0079] REFERENCE SIGNS LIST 1 sliced ​​veneer 2 decorative layer 3 adhesive layer 4 support layer 5 base resin 6 decorated part 7 laminate 8 injection molded resin 9 stripper drive mechanism 10 female mold 11 male mold 12 punch mold 13 stripper 14 die mold 15 pad 16 pad drive mechanism 17 side pad 18 side pad drive mechanism 19 side pad ejection allowance from die mold 20 laminate restraint point A 21 laminate restraint point B 22 laminate restraint point C 23 side pad A 24 side pad B 25 side pad C 26 side pad drive mechanism A 27 side pad drive mechanism B 28 side pad drive mechanism C 29 backing plate for side pad drive mechanism 30 spring 31 cylinder 32 side pad D 33 side pad E 34 cavity mold 35 core mold 36 Undercut processing on punch die side 37 Undercut of laminate 38 Air supply path 39 Compressed air supply machine 40 Veneer / resin laminated structure housing 41 Appearance surface 42 Secondary appearance surface 43 Corner R of R0.5 or more

Claims

1. A press molding die, which is at least one of a punch and a die, and which has a support and pressing mechanism that supports the workpiece at a position where it is not shaped during press processing and presses the workpiece in the pressure direction.

2. A press molding die as described in claim 1, further having a side pressing mechanism which supports the workpiece from a direction perpendicular to the pressure direction as the workpiece deforms during press processing, and which retreats to a surface of the press die that is continuous with the surface that contacts the workpiece as shaping progresses, thereby shaping the workpiece.

3. A press molding die according to claim 1 or 2, comprising a plurality of said pressing mechanisms.

4. A press molding die as described in claim 1 or 2, wherein the pressing mechanism has an undercut forming function for forming an undercut in the workpiece.

5. A press molding die set having a punch and a die, comprising the press molding die according to claim 1 or 2.

6. A press apparatus comprising the press molding die set according to claim 5.

7. A method for manufacturing a shaped product, comprising: a first step of placing an object to be processed on a press molding die; and a second step of pressurizing the object to be processed in the press molding die to form the object into a shaped product, wherein in the second step, the object to be processed is supported at a position where it is not shaped, and is pressed along a pressure direction while being pressurized to form the object to be processed into a shaped product.

8. A method for manufacturing a shaped product as claimed in claim 7, wherein in the second step, the object is supported in a direction perpendicular to the pressure direction as the object deforms, and the object is shaped along a surface of the press die that is continuous with the surface that contacts the object in response to the progress of shaping.

9. The method for producing a shaped product according to claim 7 or 8, further comprising an undercut forming step of forming an undercut in the object to be processed.

10. A method for manufacturing a molded product comprising the steps of: placing the shaped product obtained in claim 7 or 8 in the cavity mold of an injection molding die consisting of a cavity mold and a core mold, and clamping the cavity mold and the core mold; pouring resin into a cavity defined between the shaped product placed in the cavity mold and the core mold; and, after the resin has hardened, opening the cavity mold and the core mold, and removing a molded product made of the shaped product and the hardened resin.

11. The press molding die according to claim 2, wherein the upper surface of the side pressing mechanism is the upper surface of the die.

12. The press molding die according to claim 4, wherein the punch has a gas supply path for supplying gas for releasing the workpiece.

13. The press molding die according to claim 12, wherein the gas supply path is in contact with an undercut of the workpiece.

14. The press molding die according to claim 13, wherein the gas supply path supplies gas to at least one of a lower portion of the punch and an undercut in the workpiece.

15. A method for producing a shaped product as claimed in claim 7, further comprising: a supporting and pressing mechanism which supports the workpiece at a position where it is not shaped in the second step and presses the workpiece along the pressure direction; and a side pressing mechanism which supports the workpiece from a direction perpendicular to the pressure direction as the workpiece deforms and retreats to a surface of the press die which is continuous with the surface which contacts the workpiece as shaping progresses, thereby shaping the workpiece, wherein the supporting and pressing mechanism and the side pressing mechanism press the workpiece while sliding it.

16. A method for manufacturing a shaped product as claimed in claim 7, wherein the press molding die includes a punch, the punch having a gas supply path for supplying gas for releasing the object to be processed, and the gas supply path supplies gas to at least one of a lower portion of the punch and an undercut of the object to be processed.

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