Manufacturing method for fiber-reinforced resin molded products

Abstract

To provide a method for manufacturing a fiber-reinforced resin molded article which can transfer a reinforcement fiber base material after shaping to a molding die so as to prevent deformation, without thermosetting using a filler.SOLUTION: A method for manufacturing a fiber-reinforced resin molded article obtained by impregnating a sheet-like reinforcement fiber base material 2 with a thermosetting resin, and thermosetting the thermosetting resin includes: a mold moving set step S3 of moving a shaping upper mold 11 to a molding lower mold 22 while engaging the reinforcement fiber base material 2 shaped in a shaping step with a shaped surface 11A of a shaping upper mold 11 and bringing it into close contact with the shaped surface, and clamping the molds, and thereby delivering the reinforcement fiber base material 2 onto a molding surface 22A of the molding lower mold 22. After the mold moving set step S3, the shaped upper mold 11 is opened from the molding lower mold 22 while remaining the reinforcement fiber base material 2 on the molding surface 22A, the thermosetting resin is injected into a cavity of a molding die 20, and the thermosetting resin is thermoset.SELECTED DRAWING: Figure 6

Description

Technical Field

[0001] The present invention relates to a method for manufacturing a fiber reinforced resin molded product. Specifically, it relates to a method for manufacturing a fiber reinforced resin molded product obtained by impregnating a sheet-like reinforcing fiber base material with a thermosetting resin and thermosetting it.

Background Art

[0002] Patent Document 1 discloses a method for manufacturing a fiber reinforced resin molded product using the RTM (Resin Transfer Molding) molding method. Specifically, in the RTM molding method, first, a sheet-like reinforcing fiber base material made of reinforcing fibers such as carbon fibers and glass fibers is set in a shaping mold and shaped into a predetermined shape. Next, the shaped reinforcing fiber base material is set in the cavity of the molding mold. Then, a thermosetting resin is injected into the cavity to impregnate the reinforcing fiber base material while thermosetting it. Thereby, a fiber reinforced resin molded product, which is a resin molded product integrated with the reinforcing fiber base material, is molded.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] In the configuration described in Patent Document 1, in order to prevent the shaped reinforcing fiber base material from collapsing, the reinforcing fiber base material is thermoset using a blocking agent during shaping. Thereby, the collapse of the shaped reinforcing fiber base material when transferring it from the shaping mold to the molding mold is prevented. However, when the blocking agent is applied to the reinforcing fiber base material, there is a risk that the thermosetting resin becomes difficult to impregnate during resin molding. Also, the man-hours related to molding increase. Therefore, the present invention provides a method for manufacturing a fiber reinforced resin molded product that can transfer the shaped reinforcing fiber base material to the molding mold without collapsing it without performing thermosetting using a blocking agent. [Means for solving the problem]

[0005] As a means of solving the above problems, the method for manufacturing fiber-reinforced resin molded articles of the present invention employs the following means.

[0006] In other words, the first invention of the present invention is a method for manufacturing a fiber-reinforced resin molded product obtained by impregnating a sheet-like reinforcing fiber substrate with a thermosetting resin and thermosetting it, comprising: a shaping step of setting the reinforcing fiber substrate in a shaping mold and shaping the reinforcing fiber substrate by clamping the mold; a mold transfer and setting step of opening a movable mold having a shaping surface that fits the molding surface of a lower mold which is the lower mold for molding the thermosetting resin, and then clamping the movable mold to the lower mold while keeping the reinforcing fiber substrate in close contact with the shaping surface of the movable mold by engagement of the engaging portion, thereby transferring the reinforcing fiber substrate onto the molding surface of the lower mold; and a resin molding step of leaving the reinforcing fiber substrate on the molding surface, opening the movable mold from the lower mold, and then injecting the thermosetting resin into the cavity of the mold and thermosetting it.

[0007] According to the first invention, the mold transfer and setting process allows the reinforcing fiber substrate, after shaping, to be set into the mold without deformation while remaining in close contact with the shaping surface of the mold that responds to the transfer. Therefore, the reinforcing fiber substrate after shaping can be appropriately transferred to the mold without the need for heat curing using a sealant to solidify the shape, and a fiber-reinforced resin molded product can be molded.

[0008] The second invention of the present invention is a method for manufacturing a fiber-reinforced resin molded article in which the reinforcing fiber base material is a nonwoven fabric, in the first invention described above.

[0009] According to the second invention, it becomes possible to properly mold fiber-reinforced resin molded products using nonwoven fabrics for which heat curing treatment with a sealing agent is not practical. Furthermore, since nonwoven fabrics are less prone to springback than woven or knitted fabrics, the reinforcing fiber base material after shaping can be made less prone to deformation. In addition, by using nonwoven fabric as the reinforcing fiber base material, it is possible to create a structure that is less prone to fraying at the cut surface than woven or knitted fabrics. Therefore, the shaping of the reinforcing fiber base material and the cutting of the edges after shaping can be performed appropriately.

[0010] The third invention of the present invention is a method for manufacturing a fiber-reinforced resin molded product, further comprising a base material cutting step in which, after the shaping step, the end of the reinforcing fiber base material is cut by a cutting blade provided inside the shaping mold while the shaping mold is clamped.

[0011] According to the third invention, the cutting of the edges of the fiber-reinforced resin molded product can be performed more easily and appropriately compared to a configuration in which the edges are cut after molding. Specifically, unlike woven fabrics, nonwoven fabrics have a structure in which the thickness dimension changes significantly before and after compression by mold clamping. Even when a nonwoven fabric with such characteristics is used as a reinforcing fiber base material, it is possible to appropriately cut the edges after shaping.

[0012] The fourth invention of the present invention is a method for manufacturing a fiber-reinforced resin molded product comprising the first or second invention described above, wherein the engaging portion that brings the reinforcing fiber substrate into close contact with the shaping surface of the movable mold is a surface layer film that constitutes the design surface of the fiber-reinforced resin molded product after molding, and the surface layer film that is set together with the reinforcing fiber substrate in the shaping mold and brings the reinforcing fiber substrate into close contact with the shaping surface of the movable mold by vacuuming after molding.

[0013] According to the fourth invention, by using a surface layer film that constitutes the design surface of a fiber-reinforced resin molded product after molding, the reinforcing fiber base material can be rationally and appropriately adhered to a movable shaping surface during shaping. [Brief explanation of the drawing]

[0014] [Figure 1] It is a perspective view showing a schematic configuration of a fiber reinforced resin molded product according to the first embodiment. [Figure 2] It is a flowchart showing a method of manufacturing a fiber reinforced resin molded product. [Figure 3] It is a view showing a step of setting a reinforcing fiber base material in a shaping die. [Figure 4] It is a view showing a shaping step. [Figure 5] It is a view showing a step of cutting an end portion of a reinforcing fiber base material while clamping the shaping die. [Figure 6] It is a view showing a step of moving the reinforcing fiber base material to the lower shaping die while being adhered to the upper shaping die after mold opening. [Figure 7] It is a view showing a step of clamping the upper shaping die to the lower shaping die. [Figure 8] It is a view showing a step of opening the upper shaping die from the lower shaping die. [Figure 9] It is a view showing a step of clamping the upper molding die to the lower molding die. [Figure 10] It is a view showing a step of depressurizing the cavity inside the molding die. [Figure 11] It is a view showing a step of filling a thermosetting resin into the cavity. [Figure 12] It is a view showing a step of opening the on-off valve on the upstream side. [Figure 13] It is a view showing a step of opening the next on-off valve. [Figure 14] It is a view showing a step of opening the next on-off valve further. [Figure 15] It is a view showing a state where air inside the cavity is discharged by the on-off repeating step. [Figure 16] It is a view showing a step of opening the upper molding die from the lower molding die to demold the product.

BEST MODE FOR CARRYING OUT THE INVENTION

[0015] Hereinafter, embodiments for carrying out the present invention will be described with reference to the drawings.

[0016] 《First Embodiment》 (Method for manufacturing fiber-reinforced resin molded product 1) First, a fiber-reinforced resin molded article (hereinafter referred to as "molded article") 1 and its manufacturing method (hereinafter referred to as "this manufacturing method") according to the first embodiment of the present invention will be described using Figures 1 to 16. In the following description, if a specific reference figure is not shown, or if there is no reference numeral corresponding to a reference figure, one of Figures 1 to 16 will be referred to as appropriate.

[0017] As shown in Figure 1, the molded product 1 is configured as the frame of the seat back 101 of the vehicle seat 100. Specifically, the molded product 1 is configured as a shell-shaped frame with a concave shape that is curved to support the back of the occupant. A back pad (not shown), which is a cushioning material for elastically supporting the back of the occupant, is provided on the front of the molded product 1, which is the shell-shaped frame.

[0018] The molded product 1 is made of a composite material formed by impregnating a sheet-like reinforcing fiber base material 2 with a thermosetting resin 3 and integrally thermosetting it. The molded product 1 has a shape in which the entire surface is gently curved into a concave shape, and the peripheral edges are bent upwards.

[0019] The molded product 1 is molded using the RTM (Resin Transfer Molding) method. Specifically, as shown in Figure 2, the molded product 1 is molded in the following order: shaping step S1, base material cutting step S2, mold transfer and setting step S3, depressurization step S4, resin injection step S5, opening and closing repeated step S6, and demolding step S7. The depressurization step S4, resin injection step S5, and opening and closing repeated step S6 correspond to the resin molding step SR.

[0020] The shaping process S1 is a process in which a sheet-like reinforcing fiber base material 2 is shaped into a product shape using a shaping mold 10, as shown in Figures 3 and 4. The shaping mold 10 comprises an upper shaping mold 11 and a lower shaping mold 12, both equipped with shaping surfaces 11A and 12A that can shape the reinforcing fiber base material 2 to match the product shape. The base material cutting process S2 is a process in which the ends of the shaped reinforcing fiber base material 2 are cut by a cutting blade 13 provided inside the shaping mold 10 to form the product shape, as shown in Figure 5.

[0021] The mold transfer and setting process S3 is a process in which, after opening the mold shaping mold 10, the shaped reinforcing fiber base material 2 is moved and set onto the lower molding mold 22, which is the lower mold of the resin molding mold 20, while keeping it in close contact with the upper molding mold 11, which is the upper mold of the mold shaping mold 10. The depressurization process S4 is a process in which, after clamping the molding mold 20 as shown in Figure 9, the cavity C in which the reinforcing fiber base material 2 is set is vacuumed through the vent 21C, as shown in Figure 10.

[0022] The resin injection process S5 is a process in which thermosetting resin 3 is injected and filled into the depressurized cavity C, as shown in Figure 11. The opening and closing repeating process S6 is a process in which the vent 21C is repeatedly opened and closed during the resin injection process S5, as shown in Figures 12 to 14, thereby repeatedly maintaining and depressurizing the pressure inside the cavity C through the vent 21C. Through this process, as shown in Figure 15, the air (bubbles) inside the cavity C is crushed and gradually discharged to the outside. The demolding process S7 is a process in which the molded product 1, which has been formed by thermosetting by heating the mold 20, is demolded along with the opening of the mold 20, as shown in Figure 16.

[0023] As shown in Figures 6 to 8, the mold 20 comprises an upper mold 21 and a lower mold 22, both equipped with molding surfaces 21A and 22A capable of resin molding the reinforcing fiber base material 2 set in its cavity C into a shape that matches the shaped product. The shaping surface 11A of the upper mold 11 is formed to correspond to the surface shape of the molding surface 21A of the upper mold 21, i.e., to be substantially the same surface shape. Similarly, the shaping surface 12A of the lower mold 12 is formed to correspond to the surface shape of the molding surface 22A of the lower mold 22, i.e., to be substantially the same surface shape.

[0024] According to this manufacturing method, in the mold transfer and setting step S3 (see Figures 6 to 8), the shaped reinforcing fiber base material 2 can be moved to the molding lower mold 22 while remaining in close contact with the shaping upper mold 11 and set in the molding lower mold 22. In other words, the shaped reinforcing fiber base material 2 can be transferred to the molding lower mold 22 while remaining in close contact with the shaping upper mold 11 without being removed. Therefore, the reinforcing fiber base material 2 can be transferred to the molding lower mold 22 without losing its shape, even without using a sealing agent to heat-cure the reinforcing fiber base material 2 into its shaped form.

[0025] Furthermore, according to this manufacturing method, the thermosetting resin 3 can be impregnated into the reinforcing fiber substrate 2 and thermoset while the air in the cavity C is properly discharged through the repeated opening and closing process S6 (see Figures 12 to 14). Therefore, the occurrence of voids in the molded product 1 can be properly suppressed.

[0026] The details of each of the above-mentioned processes will be explained in order below. First, the shaping process S1 will be explained with reference to Figures 3 and 4. As shown in Figure 3, in the shaping process S1, first, the sheet-like reinforcing fiber base material 2 is set together with the thin film surface layer 4 on the shaping surface 12A of the lower shaping mold 12, which is the lower mold of the shaping mold 10.

[0027] The reinforcing fiber base material 2 consists of a laminate formed by stacking multiple layers of carbon fiber nonwoven fabric. The reinforcing fiber base material 2 may be made of glass fibers or aramid fibers in addition to carbon fibers. Furthermore, the reinforcing fiber base material 2 may be made of woven fabric or knitted fabric in addition to nonwoven fabric. The surface layer film 4 is a synthetic resin film that forms a thin film-like design surface on the surface of the molded product 1. The surface layer film 4 is set on the forming surface 12A of the forming mold 12 before the reinforcing fiber base material 2, and the reinforcing fiber base material 2 is set on top of it in a laminated manner.

[0028] Next, as shown in Figure 4, the upper mold 11, which is the upper mold of the forming mold 10, is clamped onto the lower mold 12. As a result, the surface film 4 and the reinforcing fiber base material 2 set on the lower mold 12 are pressed between the forming surface 12A of the lower mold 12 and the forming surface 11A of the upper mold 11, and are formed into a shape along these forming surfaces 12A and 11A.

[0029] Next, as shown in Figure 5, in the base material cutting process S2, with the shaping mold 10 still clamped, the ends of the reinforcing fiber base material 2 and surface film 4 inside the shaping mold 10 are cut by a cutting blade 13 provided inside the shaping mold 10. Although not specifically shown in the illustration, the cutting blade 13 is set inside the upper shaping mold 11 and, together with the clamping, is pressed towards the shaping surface 12A of the lower shaping mold 12, thereby cutting the ends of the reinforcing fiber base material 2 and surface film 4 into the product shape.

[0030] In the above-described substrate cutting process S2, the edges of the reinforcing fiber substrate 2 and the surface film 4 are cut, making cutting easier compared to a configuration where the edges are cut after resin molding, because the edges are not yet hardened. Furthermore, since the reinforcing fiber substrate 2 is made of nonwoven fabric, the cut surface can be made less prone to fraying.

[0031] Next, the mold transfer and setting process S3 will be explained with reference to Figures 6 to 8. As shown in Figure 6, in the mold transfer and setting process S3, first, the upper mold 11 is opened from the lower mold 12. At this time, a vacuum pump (not shown) is used to open the upper mold 11 while applying vacuum to bring the reinforcing fiber substrate 2 and the surface film 4 into close contact with the forming surface 11A of the upper mold 11 through the ventilation holes (not shown) formed in the upper mold 11.

[0032] As a result, the surface film 4 acts as a sealing material to enhance airtightness, and the reinforcing fiber base material 2 and the surface film 4 remain in close contact with the shape of the shaping surface 11A of the upper shaping mold 11, that is, they are removed from the lower shaping mold 12 together with the upper shaping mold 11 while maintaining their shaped form without disrupting it. Here, the surface film 4 corresponds to the "engaging portion" of the present invention.

[0033] Next, the opened upper mold 11 is moved onto the lower mold 22 of the mold 20, which is in the open position, and clamped to the lower mold 22 as shown in Figure 7. Specifically, the clamping of the upper mold 11 to the lower mold 22 is performed by passing a positioning pin provided on one of them through a hole in the other. Through this clamping, the reinforcing fiber base material 2 and surface film 4 attached to the upper mold 11 are set on the molding surface 22A of the lower mold 22.

[0034] The shaping surface 11A of the upper shaping mold 11 has substantially the same surface shape as the molding surface 21A of the upper molding mold 21. Therefore, by clamping the upper shaping mold 11 onto the lower molding mold 22, the reinforcing fiber base material 2 and surface film 4, which are in close contact with the shaping surface 11A, are set to be positioned along the molding surface 22A of the lower molding mold 22. Here, the upper shaping mold 11 corresponds to the "movable mold" of the present invention.

[0035] Next, with the upper mold 11 still clamped to the lower mold 22, the vacuum applied to the upper mold 11 is released. This causes the reinforcing fiber substrate 2 and surface film 4, which were in close contact with the shaping surface 11A of the upper mold 11, to fall onto the molding surface 22A of the lower mold 22. Next, as shown in Figure 8, the upper mold 11 is opened from the lower mold 22. This causes only the upper mold 11 to be opened from the lower mold 22, while the reinforcing fiber substrate 2 and surface film 4 remain on the molding surface 22A of the lower mold 22.

[0036] After the mold is opened, the reinforcing fiber base material 2 and the surface film 4 do not lift up from the molding surface 22A of the lower mold 22, but are retained in the shape of the product that conforms to the shape of the molding surface 22A, i.e., in their formed shape. This is because the reinforcing fiber base material 2, which is made of carbon fiber nonwoven fabric, has properties that make it easy to maintain its formed shape and is resistant to springback even after being unloaded by opening the mold.

[0037] Furthermore, the surface film 4, being composed of a thin, flexible film, has weaker restorative force compared to the reinforcing fiber base material 2, and does not exert enough elastic force to deform the reinforcing fiber base material 2. Therefore, in this mold transfer and setting process S3, the formed reinforcing fiber base material 2 and surface film 4 can be set and transferred to the molding lower mold 22 without losing their shape, while remaining in close contact with the forming upper mold 11.

[0038] Next, the resin molding process SR (reduced pressure process S4, resin injection process S5, and opening / closing repeating process S6) will be explained with reference to Figures 9 to 14. As shown in Figure 9, first, in the reduced pressure process S4, the upper mold 21 is clamped onto the lower mold 22, which is set with the reinforcing fiber substrate 2 and the surface film 4.

[0039] Then, as shown in Figure 10, the cavity C formed by the molding surface 21A of the clamped upper mold 21 and the molding surface 22A of the lower mold 22 is evacuated using a vacuum pump 40 connected via a suction pipe 41. The vacuum pump 40 applies suction pressure to the cavity C from the outside via the vent 21C formed in the upper mold 21 and the suction pipe 41 connected thereto, thereby reducing the pressure inside the cavity C. The suction pipe 41 is provided with four on-off valves V1 to V4 at positions in the direction of flow. Each on-off valve V1 to V4 is spaced apart from each other and can be individually opened or closed via a control device (not shown).

[0040] Next, as shown in Figure 11, liquid thermosetting resin 3 is injected into the depressurized cavity C using the resin supply device 30. The resin supply device 30 injects the liquid thermosetting resin 3 into the cavity C through the nozzle 31 via the injection hole 21B formed in the upper mold 21.

[0041] The thermosetting resin 3 used in this embodiment is a two-component epoxy resin consisting of a main component and a curing agent. The resin supply device 30 mixes the main component and curing agent of the epoxy resin in a predetermined mixing ratio in a mixing head (not shown), and injects the mixture into the cavity C through the injection hole 21B via a nozzle 31 at the tip of the mixing head.

[0042] The thermosetting resin 3 may consist of epoxy resin, phenolic resin, unsaturated polyester resin, vinyl ester resin, or urethane resin. Although not shown in the figure, a sealing member is provided on the periphery of the lower surface of the upper molding mold 21, which is pressed between it and the upper surface of the lower molding mold 22 during clamping to seal the periphery of the cavity C.

[0043] In the depressurization process S4 shown in Figure 10, after clamping the upper mold 21 onto the lower mold 22, first, the gas (air) in the cavity C is discharged to the outside through the vent 21C and suction pipe 41 using a vacuum pump 40, thereby reducing the pressure inside the cavity C to a predetermined negative pressure. At this time, the four on-off valves V1 to V4 are left open.

[0044] Then, once the pressure inside cavity C has been reduced to a predetermined negative pressure, the four on-off valves V1 to V4 are closed. As a result, in addition to cavity C, each space partitioned by the four on-off valves V1 to V4 is also kept in an airtight state with a predetermined negative pressure. After closing the four on-off valves V1 to V4, the operation of the vacuum pump 40 is stopped.

[0045] Subsequently, in the resin injection process S5 shown in Figure 11, liquid thermosetting resin 3 is injected into the depressurized cavity C from the resin supply device 30. This injection under reduced pressure ensures that the liquid thermosetting resin 3 fills the cavity C evenly. As a result, the liquid thermosetting resin 3 injected into the cavity C impregnates the reinforcing fiber substrate 2 within the cavity C and flows through the cavity C, pushing out any remaining air bubbles in the reinforcing fiber substrate 2.

[0046] Since the thermosetting resin 3 injected into cavity C is made of epoxy resin, it has low viscosity in its liquid state. Therefore, even if the injection pressure from the resin supply device 30 is low, the thermosetting resin 3 is filled so that it spreads widely throughout cavity C and is properly impregnated into the reinforcing fiber substrate 2. As the liquid thermosetting resin 3 fills cavity C, air bubbles in cavity C rise to the surface and move towards vent 21C.

[0047] When the thermosetting resin 3 is filled into cavity C, the injection pressure of the thermosetting resin 3 is applied to cavity C, which is maintained by the closing of each on-off valve V1 to V4, and the internal pressure inside cavity C increases. As a result, as shown in Figure 15, if air bubbles remain in cavity C, these bubbles are crushed by the internal pressure of cavity C. However, as the bubbles are crushed, the internal pressure of cavity C also gradually increases, and once the internal pressure exceeds a certain level, the injection pressure from the resin supply device 30 alone is no longer sufficient to crush the bubbles further.

[0048] Next, as shown in Figures 12 to 14, in the opening and closing repetition process S6, while continuing to inject the thermosetting resin 3 by the resin supply device 30, each on-off valve V1 to V3 is opened sequentially from the upstream side (on-off valve V1) closest to the cavity C. As a result, the pressure inside the cavity C is repeatedly maintained and depressurized, and any air bubbles remaining inside the cavity C are gradually discharged into the vent 21C by being pushed aside by the injection pressure of the thermosetting resin 3.

[0049] Specifically, as shown in Figure 12, in the repeated opening and closing process S6, the upstream on-off valve V1 is opened first. As a result, the negative pressure between the opened on-off valve V1 and the closed on-off valve V2 causes the pressure inside the cavity C to decrease.

[0050] Subsequently, as the injection of thermosetting resin 3 by the resin supply device 30 continues, the internal pressure of cavity C rises again above a certain level and reaches a pressure-holding state. During this time, some of the thermosetting resin 3 filled in cavity C leaks out from vent 21C into suction pipe 41, but the leakage of thermosetting resin 3 is limited to just before the second on-off valve V2 from the upstream side, which is closed.

[0051] Next, as shown in Figure 13, the second on-off valve V2 from the upstream side is opened. As a result, the negative pressure between the opened on-off valve V2 and the closed on-off valve V3 reduces the pressure inside cavity C. Subsequently, as the injection of thermosetting resin 3 by the resin supply device 30 continues, the internal pressure of cavity C rises again to above a certain level and reaches a holding pressure state. During this time, some of the thermosetting resin 3 filled in cavity C leaks from the vent 21C into the suction pipe 41, but the leakage of thermosetting resin 3 is limited to before the third on-off valve V3 from the upstream side, which is closed.

[0052] Next, as shown in Figure 14, the third on-off valve V3 from the upstream side is opened. As a result, the negative pressure between the opened on-off valve V3 and the closed on-off valve V4 reduces the pressure inside cavity C. Subsequently, as the injection of thermosetting resin 3 by the resin supply device 30 continues, the internal pressure of cavity C rises again to above a certain level and reaches a holding pressure state. During this time, some of the thermosetting resin 3 filled in cavity C leaks from the vent 21C into the suction pipe 41, but the leakage of thermosetting resin 3 is limited to before the fourth on-off valve V4 from the upstream side, which is closed.

[0053] The stepwise opening of the above-mentioned valves V1 to V3 repeatedly reduces pressure and maintains pressure within the cavity C. After the opening and closing process S6, the thermosetting resin 3 is filled into the cavity C, and then the injection of the thermosetting resin 3 by the resin supply device 30 is stopped, and the cavity C is maintained at a pressure. In this state, as the mold 20 is heated, the thermosetting resin 3 in the cavity C is heat-cured, thereby forming a molded product 1 in which the surface film 4 and reinforcing fiber substrate 2 and the thermosetting resin 3 are integrated.

[0054] Subsequently, in the demolding process S7 shown in Figure 16, the mold 20 is opened and the molded product 1 is removed from the lower mold 22. Through these steps, a molded product 1 without voids on its surface can be formed.

[0055] In summary, the manufacturing method for the fiber-reinforced resin molded product 1 according to this embodiment has the following configuration. The reference numerals in parentheses below correspond to the respective configurations shown in the above embodiment.

[0056] In other words, the method for manufacturing the fiber-reinforced resin molded product (1) is a method for manufacturing the fiber-reinforced resin molded product (1) obtained by impregnating a sheet-shaped reinforcing fiber base material (2) with a thermosetting resin (3) and then thermosetting it. The method for manufacturing the fiber-reinforced resin molded product (1) comprises a shaping step (S1), a mold transfer and setting step (S3), and a resin molding step (SR). The shaping step (S1) is a step in which the reinforcing fiber base material (2) is set in a shaping mold (10) and the reinforcing fiber base material (2) is shaped by clamping the mold.

[0057] Furthermore, the mold transfer setting process (S3) is a process in which, after opening the mold of the movable mold (11), which has a shaping surface (11A) that fits the molding surface (22A) of the lower molding mold (22), which is the lower mold of the molding die (20) for molding the thermosetting resin (3) among the shaping molds (10), the movable mold (11) is clamped onto the lower molding die (22) while the reinforcing fiber base material (2) is in close contact with the shaping surface (11A) of the movable mold (11) by the engagement of the engagement part (4), thereby transferring the reinforcing fiber base material (2) onto the molding surface (22A) of the lower molding die (22). The resin molding process (SR) is a process in which, after opening the mold of the movable mold (11) from the lower molding die (22) with the reinforcing fiber base material (2) remaining on the molding surface (22A), the thermosetting resin (3) is injected into the cavity (C) of the molding die (20) and thermoset.

[0058] According to the above configuration, the mold transfer and setting process (S3) allows the reinforcing fiber base material (2) after shaping to be set in the lower molding mold (22) without deformation, while remaining in close contact with the shaping surface (11A) of the movable mold (11). Therefore, the reinforcing fiber base material (2) after shaping can be appropriately transferred to the molding mold (20) and the fiber-reinforced resin molded product (1) can be molded without performing shape solidification by heat curing using a sealant.

[0059] Furthermore, the reinforcing fiber base material (2) is made of nonwoven fabric. With the above configuration, it becomes possible to appropriately mold fiber-reinforced resin molded products (1) using nonwoven fabric, for which heat curing treatment with a sealing agent is not practical. In addition, since nonwoven fabric is less prone to springback than woven or knitted fabrics, the reinforcing fiber base material (2) after shaping can be made less prone to deformation. Also, by making the reinforcing fiber base material (2) a nonwoven fabric, it is possible to create a structure that is less prone to fraying at the cut surface than woven or knitted fabrics. Therefore, the shaping of the reinforcing fiber base material (2) and the cutting of the edges after shaping can be performed appropriately.

[0060] Furthermore, the manufacturing method of the fiber-reinforced resin molded product (1) further includes a base material cutting step (S2) in which, after the shaping step (S1), the ends of the reinforcing fiber base material (2) are cut by a cutting blade (13) provided inside the shaping mold (10) while the shaping mold (10) is still clamped. With the above configuration, the ends of the fiber-reinforced resin molded product (1) can be cut more easily and appropriately than in a configuration in which the ends are cut after molding. Specifically, unlike woven fabrics, nonwoven fabrics have a structure in which the thickness dimension changes significantly before and after compression by clamping the mold, but even when a nonwoven fabric with such characteristics is used as the reinforcing fiber base material (2), it is possible to appropriately cut the ends after shaping.

[0061] Furthermore, the engaging portion (4) that brings the reinforcing fiber base material (2) into close contact with the shaping surface (11A) of the movable mold (11) is a surface film (4) that constitutes the design surface of the molded fiber-reinforced resin product (1) after molding. The surface film (4) is set in the shaping mold (10) together with the reinforcing fiber base material (2) and, after shaping, is vacuum-sealed to bring the reinforcing fiber base material (2) into close contact with the shaping surface (11A) of the movable mold (11). With the above configuration, the surface film (4) that constitutes the design surface of the molded fiber-reinforced resin product (1) after molding can be used to bring the reinforcing fiber base material (2) into close contact with the shaping surface (11A) of the movable mold (11) during shaping in a rational and appropriate manner.

[0062] Regarding other embodiments: Although the embodiments of the present invention have been described above using one embodiment, the present invention can be implemented in various forms other than those described above.

[0063] 1. The manufacturing method for the fiber-reinforced resin molded article of the present invention may be any so-called RTM (Resin Transfer Molding) molding method, or it may be a VaRTM (Vacuum assisted Resin Transfer Molding) molding method. Furthermore, the fiber-reinforced resin molded article may be applied not only to seats for vehicles such as automobiles and railways, but also to seats for vehicles other than automobiles, such as aircraft and ships. It may also be applied to interior parts of vehicles.

[0064] 2. The movable mold can be any mold having a shaping surface that conforms to the molding surface of the lower mold, and may consist of a shaping upper mold or a shaping lower mold. In other words, the shaping lower mold is inverted after opening, and the reinforcing fiber base material is transferred onto the molding surface of the lower mold by clamping it to the lower mold.

[0065] 3. The engagement portion that engages the shaped reinforcing fiber substrate with the shaped surface of the movable type can be a surface film that is vacuum-sealed to the movable type, or it can be a clamp or magnet that fixes the reinforcing fiber substrate to the movable type. [Explanation of symbols]

[0066] 1. Fiber-reinforced resin molded product 2. Reinforcement fiber base material 3 Thermosetting resin 4. Surface film (engaging portion) 10 Shaping mold 11. Formation-oriented type (mobile-compatible type) 11A Shaping surface 12 Imprinting mold 12A Shaping surface 13 Cutting blade 20 mold 21 Upper mold 21A Molding surface 21B Injection hole 21C Bent 22 Lower mold 22A Molding surface C Cavity 30 Resin supply device 31 nozzles 40 Vacuum pump 41 Suction tube V1~V4 Shut-off valves S1 Shaping process S2 Base material cutting process S3 Type Transfer Set Process S4 Depressurization Process S5 Resin injection process S6 Repeated opening and closing process S7 Demolding process SR resin molding process 100 Vehicle Seats 101 Seatback

Claims

1. A method for producing a fiber-reinforced resin molded product obtained by impregnating a sheet-like reinforcing fiber substrate with a thermosetting resin and then thermosetting it, A forming step in which the reinforcing fiber base material is set in a forming mold and shaped by clamping the mold, A mold transfer setting step is performed by opening the mold of a movable mold having a shaping surface that fits the molding surface of a lower mold which is the lower mold for molding the thermosetting resin, and then clamping the movable mold onto the molding surface of the lower mold with the reinforcing fiber substrate sandwiched in between, while keeping the reinforcing fiber substrate in close contact with the shaping surface of the movable mold by engagement of the engaging portion, thereby transferring the reinforcing fiber substrate onto the molding surface of the lower mold, A method for manufacturing a fiber-reinforced resin molded product, comprising a resin molding step of leaving the reinforcing fiber substrate on the molding surface, opening the movable mold from the lower molding mold, and then injecting the thermosetting resin into the cavity of the molding mold and thermosetting it.

2. A method for manufacturing a fiber-reinforced resin molded article according to claim 1, A method for manufacturing a fiber-reinforced resin molded product in which the reinforcing fiber base material is a nonwoven fabric.

3. A method for manufacturing a fiber-reinforced resin molded article according to claim 2, A method for manufacturing a fiber-reinforced resin molded product, further comprising a base material cutting step in which, after the shaping step, the end of the reinforcing fiber base material is cut by a cutting blade provided inside the shaping mold while the shaping mold is clamped.

4. A method for producing a fiber-reinforced resin molded product obtained by impregnating a sheet-like reinforcing fiber substrate with a thermosetting resin and then thermosetting it, A forming step in which the reinforcing fiber base material is set in a forming mold and shaped by clamping the mold, A mold transfer setting step is performed by opening the mold of a movable mold having a shaping surface that fits the molding surface of the lower mold, which is the lower mold for molding the thermosetting resin, and then clamping the movable mold to the lower mold while keeping the reinforcing fiber substrate in close contact with the shaping surface of the movable mold by engagement of the engaging portion, thereby transferring the reinforcing fiber substrate onto the molding surface of the lower mold, The process includes a resin molding step in which the reinforcing fiber substrate is left on the molding surface, the movable mold is opened from the lower molding mold, and the thermosetting resin is injected into the cavity of the molding mold and thermosetting is performed. A method for manufacturing a fiber-reinforced resin molded product comprising: an engaging portion that brings the reinforcing fiber substrate into close contact with the movable molded surface, the surface film which constitutes the design surface of the fiber-reinforced resin molded product after molding, and the surface film which is set together with the reinforcing fiber substrate in the molded mold and brings the reinforcing fiber substrate into close contact with the movable molded surface by vacuuming after molding.

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