JP2005271551A - Resin transfer molding method and molding apparatus for it - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a RTM molding method capable of injecting and filling a resin in a short time without generating a bias or turbulence of reinforcing fibers and a RTM molding apparatus. <P>SOLUTION: The resin transfer molding method comprises impregnating a matrix resin 12 into a reinforcing fiber layer 10 arranged at a molding cavity in a molding die 1 and heating and hardening it. The reinforcing fiber layer 10 and the matrix resin 12 are charged into the open molding die 1, the charged matrix resin 12 is developed on the surface of the reinforcing fiber layer 10 in the molding cavity according to the clamping of the die and the matrix resin 12 developed after the die clamping is impregnated into the reinforcing fiber layer 10. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a resin transfer molding (hereinafter referred to as RTM) molding method, and more particularly to an RTM molding method suitable for uniform impregnation of a matrix resin.

  Conventionally, various RTM molding methods have been proposed for molding resin products made of fiber reinforced plastic (hereinafter referred to as FRP) (see Patent Documents 1 to 3).

These are all made by placing reinforcing fibers in a mold, filling the mold with a thermosetting resin that is a matrix resin in a state where the mold is sealed, uniformly impregnating the reinforcing fibers, and heat curing. A resin product made of FRP is molded.
JP 2001-260238 A Japanese Patent Laid-Open No. 08-323870 Japanese Patent Laid-Open No. 11-348059

  However, in the above conventional example, the reinforcing fiber arranged in a closed mold is filled and impregnated with a thermosetting matrix resin. Therefore, in order to fill as fast as possible, the resin injection pressure may be increased. Although effective, the reinforcing fibers arranged in the mold are biased and disordered in orientation, and it is difficult to effectively shorten the resin filling time.

  In Patent Document 3, a layer for adjusting the resin permeability is provided between the resin inlet and the reinforcing fiber, the resin pressure applied to the reinforcing fiber layer is made uniform, and the fiber orientation disorder of the reinforcing fiber is prevented. However, since the inflow amount of the resin is limited by the transmittance adjusting member, the injection pressure needs to be further increased, which is not practical.

  Therefore, the present invention has been made in view of the above problems, and an object of the present invention is to provide an RTM molding method and an RTM molding apparatus that can be injected and filled in a short time without causing unevenness or disturbance of reinforcing fibers.

  The present invention is a resin transfer molding molding method in which a reinforcing fiber layer disposed in a molding cavity of a mold is impregnated with a matrix resin and heat-cured, and the reinforcing fiber layer and the matrix resin are placed between the molds in an open state. The matrix resin was spread on the surface of the reinforcing fiber layer in the molding cavity according to the mold closing, and the reinforcing fiber layer was impregnated with the matrix resin developed by the subsequent mold closing.

  Accordingly, the present invention is a resin transfer molding method in which a reinforcing fiber layer disposed in a molding cavity of a mold is impregnated with a matrix resin and cured by heating, and the reinforcing fiber layer and the matrix resin are formed between the open molds. The matrix resin was spread on the surface of the reinforcing fiber layer in the molding cavity according to the mold closing, and the reinforcing fiber layer was impregnated with the matrix resin developed by the subsequent mold closing. A uniform impregnation is possible by spreading the matrix resin. Therefore, the molding time can be greatly shortened.

  Hereinafter, the RTM molding method and the RTM molding apparatus of the present invention will be described based on each embodiment.

(First embodiment)
1 to 3 show a first embodiment of an RTM molding method and an RTM molding apparatus to which the present invention is applied, FIG. 1 is a sectional view of the RTM molding apparatus, FIG. 2 is a process diagram showing an RTM molding process, and FIG. FIG. 4 is a partial cross-sectional view showing the flow state of the injected resin during resin injection, and FIG. 4 is a partial cross-sectional view showing the resin flow state when the mold is closed.

  In FIG. 1, an RTM molding device includes a molding die 1 composed of an upper die 2 and a lower die 3, and a resin injection device 6 that injects a matrix resin into the molding die 1 from a resin injection port 5 via an on-off valve 4. And a suction device 8 for sucking air in the mold 1 from the suction port 7.

  The mold 1 is formed with an upper mold 2 and a lower mold 3 so as to form a molding cavity when the mold is closed. In the upper and lower molds 1, a plurality of mold temperature control pipes 9 including heating / cooling pipes functioning to cure the molded product by heating the molding cavities when the molds are closed are arranged. As shown in the example, the molding cavity is provided between the upper and lower molds 2 and 3 with the lower mold 3 side depressed and the upper mold 2 protruding, and is inserted into the cavity surface 3A of the lower mold 3 when the mold is opened. The reinforced fiber layer 10 of the FRP is stably held. Further, the cavity surface 3A of the lower mold 3 is recessed toward the lower side 3, so that it functions to store the injected matrix resin in the cavity surface 3A.

  Around the periphery of the molding cavity surface 3A of the lower mold 3, a seal accommodating groove 3B having a predetermined depth is provided on the circumference so as to surround a region to be the molding cavity 3A. A lower portion of the seal seal 11 having a diameter larger than the depth of the seal accommodation groove 3B is inserted into the seal accommodation groove 3B, and an upper portion of the seal seal 11 is protruded above the seal accommodation groove 3B. . The upper mold 2 is formed with a seal surface 2B that contacts the sealing seal 11 when the mold is closed and seals the molding cavity.

  The hermetic seal 11 is, for example, a general round bar-like rubber seal, and may have heat resistance for RTM molding. The relationship between the diameter of the hermetic seal 11 and the depth of the seal housing groove 3B is, for example, that if the diameter of the hermetic seal 11 is 10 mm, the depth of the seal housing groove 3B is set to 5 mm. When the strokes until the molds 2 and 3 are closed are 5 mm, the sealing seal 11 and the sealing surface 2B of the upper mold 2 come into contact with each other to block the molding cavity from the outside air.

  Further, the upper die 2 is provided with a plurality of suction ports 7 which are opened at intervals in the outer peripheral portion of the molding cavity surface 2A on the inner side of the seal surface 2B, and is opened in the central region of the molding cavity surface 2A. An inlet 5 is arranged. Although only one resin injection port 5 may be provided in the central region of the molding cavity surface 2A, the plurality of injection ports 5 avoid the peripheral region of the molding cavity surface 2A so that a plurality of the resin injection ports 5 are equally distributed. It is desirable to make it open.

  The RTM molding process by the RTM molding apparatus having the above configuration will be described below.

  FIG. 1 shows a set state of the reinforcing fiber layer 10, and the reinforcing fiber layer 10 is put into the lower mold 3 in the mold 1 that has been opened. In this step, the on-off valve 4 between the resin injecting device 6 is closed, and the suction operation of the air suction device 8 is stopped. The reinforcing fiber layer 10 to be input has a thickness corresponding to a predetermined product plate thickness, and is placed on the cavity surface 3 </ b> A of the lower mold 3.

  Subsequently, mold closing is started, and the mold closing operation is stopped when the sealing seal 11 of the lower mold 3 comes into contact with the seal surface 2B of the upper mold 2 as shown in FIG. In this state, the seal seal 11 protrudes from the seal housing groove 3B between the surface of the reinforcing fiber layer 10 placed on the lower mold 3 cavity surface 3A and the upper mold 2 cavity surface 2A (the above example). In this case, there is a gap of 5 mm), and the sealing seal 11 and the upper mold 2 seal surface 2B come into contact with each other, so that the space of the molding cavity and the outside air are blocked.

  Next, the opening / closing valve 4 is opened, and a predetermined amount of thermosetting resin 12 calculated from the fiber content in advance is injected into the molding cavity from the resin injection device 6 through the resin injection port 5. A part of the thermosetting resin 12 injected into the molding cavity penetrates into the reinforcing fiber layer 10, but most of the thermosetting resin 12 is molded along the upper side of the reinforcing fiber layer 10 as indicated by an arrow in FIG. 3. It expands in the cavity. When the injection of the thermosetting resin 12 is finished, the on-off valve 4 is closed.

  Next, the air suction device 8 is activated, and the air in the molding cavity in the molding die 1 is sucked through the suction port 7 and the upper die 2 is changed to the lower die 3 as shown in FIG. The mold closing approaching is resumed. In this process, the resin 12 placed on the reinforcing fiber layer 10 is separated from the surface of the reinforcing fiber layer 10 by reducing the gap between the surface of the reinforcing fiber layer 10 and the molding cavity surface 2A of the upper mold 2. It expands into the space between the molding cavity surface 2A of the upper mold 2 and spreads (expands) over the entire space when the space volume is thinly reduced to a size corresponding to the amount of injected resin.

  The filling speed at this time is as follows. In the conventional method in which the resin is injected into the cavity that has been clamped, the injected resin 12 passes through the gaps between the fibers of the reinforcing fiber layer 10 and fills the entire cavity as shown in FIG. In the present embodiment, the resin 12 spreads in the space between the reinforcing fiber layer 10 and the cavity surface 2A of the upper mold 2 while the resin 12 spreads extremely slowly. Because it goes, there is no resistance to diffusion and it can be spread throughout the space in a short time.

  In the subsequent mold closing operation, since the space in the molding cavity is substantially in a vacuum state, as shown in FIG. 4, the injected resin 12 is forcibly pushed into the gap of the reinforcing fiber layer 10 and impregnated. As a result, when the mold closing is completed, the injection resin 12 is impregnated in the entire reinforcing fiber layer 10.

  The impregnation speed at this time is different from the conventional method in which the resin 12 injected by pressure is impregnated in the gaps between the fibers of the reinforcing fiber layer 10. In this embodiment, the resin 12 is injected into the reinforcing fiber layer 10 by mold closing. Since the reinforcing fiber layer 10 is impregnated with the resin 12 in the thickness direction from the surface side, the reinforcing fiber 10 can be greatly increased without being biased or disturbed. That is, impregnation can be completed in a short time.

  Next, in the mold 1, the heating medium is circulated through the mold temperature control pipe 9 to heat the molding cavity, the thermosetting resin 12 in the molding cavity is cured, and the reinforcing fiber layer 10 and the thermosetting resin 12. FRP is made by combining with the above.

  At the stage where the resin 12 has been cured, as shown in FIG. 2C, the mold 1 is opened and the FRP product W is taken out.

  In the above process, it is described that the mold 1 is heated by the mold temperature control pipe 9 when the reinforcing fiber layer 10 is completely impregnated with the resin 12. It may be started before the reinforcing fiber layer 10 is introduced into the opened mold 1 in advance, and in this way, the curing time of the thermosetting resin 12 can be shortened.

  Further, when the mold 1 is not made of metal, for example, when an FRP mold is used, it is lightweight, and therefore, after the mold is closed, the closed mold itself is allowed to pass for a set time in a heating furnace. By doing so, the thermosetting resin may be cured.

  According to the RTM molding apparatus and the RTM molding method described above, a state where there is a gap between the injected reinforcing fiber layer 10 and the upper mold 2 instead of injecting the resin into the clamped cavity as in the prior art. Since the resin 12 is injected at, the set amount of the resin 12 can be injected into the mold 1 in a short time. Further, by closing the mold 1, the resin 12 in the gap between the reinforcing fiber layer 10 and the upper mold 2 is spread over the entire cavity-shaped surface 2A, and in the next stage, only the thickness direction in the thickness direction of the entire shaped surface 2A. Can be impregnated with resin 12. For this reason, the molding time can be greatly shortened.

  In the present embodiment, the following effects can be achieved.

  (A) A resin transfer molding molding method in which a reinforcing fiber layer 10 disposed in a molding cavity of the mold 1 is impregnated with a matrix resin 12 and heat-cured, and the reinforcing fiber layer 10 is formed between the molds 1 in an open state. The matrix resin 12 is introduced, and the matrix resin 12 is spread on the surface of the reinforcing fiber layer 10 in the molding cavity according to the mold closing, and the reinforcing fiber layer 10 is impregnated with the matrix resin 12 developed by the subsequent mold closing. Therefore, the matrix resin 12 is spread over the entire reinforcing fiber 10, and further, the entire reinforcing fiber layer 10 can be impregnated in the thickness direction, so that uniform impregnation is possible. Therefore, the molding time can be greatly shortened.

(A) When the matrix resin 12 is unfolded, the molding cavity is shut off from the outside air and brought into a negative pressure state. Therefore, the matrix resin 12 is rapidly expanded into the molding cavity and the matrix fiber 12 is impregnated into the reinforcing fiber layer 10. (C) The matrix resin 12 blocks the molding cavity in the middle of mold closing from the outside air and injects it as a negative pressure state. Therefore, the matrix resin 12 is introduced into the gap between the reinforcing fiber layer 10 and the upper mold 2 cavity surface 2A. The matrix resin 12 having a set filling amount can be injected into the mold in a short time.

(Second Embodiment)
6A and 6B show a second embodiment of an RTM molding apparatus and an RTM molding method to which the present invention is applied. FIG. 6A is a cross-sectional view of the RTM molding apparatus, and FIGS. 6B to 6D are RTM molding processes. FIG. In this embodiment, the molding time is shortened by injecting the matrix resin before the mold closing of the mold is started. 1 to 5 are denoted by the same reference numerals, and description thereof is omitted or simplified.

  The RTM molding apparatus of this embodiment is almost the same as the RTM molding apparatus of the first embodiment, but has a configuration in which a bag-like cavity 15 is installed at the opening end of the injection port 5 of the matrix resin 12 to the molding cavity surface 2A. It has been added. The bag-shaped cavity 15 is formed by bagging a bagging film often used for FRP molding, and has a large number of small holes (for example, about 2 mm in diameter) distributed evenly (for example, 10 mm pitch). The hole diameter and hole pitch of the small holes may be changed according to the viscosity of the matrix resin 12. Further, the size of the bag-like cavity 15 is larger than the injection amount set by the matrix resin 12, and is large enough to spread over the entire molding cavity when crushed in the molding die 1.

  When the matrix resin 12 is injected into the molding cavity from the injection port 5, the bag-shaped cavity 15 first accumulates in the bag-shaped cavity 15, and then the lower mold 3 constituting the molding cavity from the numerous small holes of the bag-shaped cavity 15. It hangs down on the cavity surface 3A.

  The RTM molding process by the RTM molding apparatus having the above configuration will be described below.

  FIG. 6A shows a set state of the fiber reinforced layer 10, where the reinforced fiber layer 10 is put into the lower mold 3 in the mold 1 that has been opened and placed on the cavity surface 3 </ b> A of the lower mold 3. Next, the opening / closing valve 4 is opened, and a predetermined amount of thermosetting resin 12 calculated from the fiber content in advance is injected into the molding cavity from the resin injection device 6 through the resin injection port 5. The thermosetting resin 12 injected into the molding cavity accumulates in the bag-like cavity 15 and hangs down on the reinforcing fiber layer 10 on the lower mold from countless small holes provided in the bag-like cavity 15. Note that the hole diameter and hole pitch of the small holes are set in advance by experiments in accordance with the viscosity of the matrix resin 12 to be used so that the matrix resin 12 dripping at this time does not spill out of the mold 1. When the injection is finished, mold closing is started.

  When the upper mold seal surface 2B comes into contact with the hermetic seal 11, the air suction device 8 is activated, and the air in the molding cavity in the mold 1 starts to be sucked through the suction port 7. In this state, the space of the molding cavity and the outside air are blocked, and the sealing seal 11 is provided between the surface of the reinforcing fiber layer 10 placed on the lower mold cavity surface 3A and the upper mold 2 cavity surface 2A. There is a gap corresponding to the dimension protruding from 3B (for example, 5 mm) (see FIG. 6B). The bag-like cavity 15 containing the matrix resin 12 expands in the molding cavity as the distance between the reinforcing fiber layer 10 and the upper mold 2 becomes smaller, and the distance between the surface of the reinforcing fiber layer 10 and the upper mold 2 cavity surface 2A. When the volume of the resin becomes almost equal to the volume of the resin, the bag-like cavity 15 containing the matrix resin 12 and the matrix resin 12 flowing out of the bag-like cavity 15 are spread over the surface of the entire molding cavity.

  Further, when the mold 1 is closed, the bag-shaped cavity 15 is pushed and crushed by the upper mold 2, and the internal matrix resin 12 is discharged through countless small holes in the bag-shaped cavity 15. Is substantially in a vacuum state, so that the matrix fiber 12 is impregnated into the reinforcing fiber layer 10, and when the mold is completely closed, the entire reinforcing fiber layer 10 is impregnated as shown in FIG. It becomes a state.

  Next, in the mold 1, the heating medium is circulated through the mold temperature control pipe 9, the molding cavity is heated, the thermosetting resin 12 in the molding cavity is cured, and the composite of the reinforcing fiber layer 10 and the thermosetting resin 12. FRP is made. At the stage where the curing of the resin is finished, as shown in FIG. 6D, the mold 1 is opened and the FRP product W is taken out. Since the crushed bag-like cavity 15 remaining on the surface of the FRP product W or the cavity surface 2A of the upper mold 2 is made of a bagging film material generally used in FRP molding, it can be easily peeled off from the FRP product W or the like.

  According to the RTM molding apparatus and the RTM molding method described above, by providing the bag-like cavity 15 having innumerable small holes between the injection port 5 and the reinforcing fiber layer 10, the set amount of the matrix resin 12 is reduced in a short time. Can be injected into the mold 1. Then, the resin 12 in the bag-shaped cavity 15 is spread over the entire molding cavity in accordance with the mold closing, and further, the reinforcing fiber layer 10 is impregnated only in the direction of the plate thickness substantially over the entire molding cavity surface 2A from the small hole of the bag-shaped cavity 15. The molding time can be greatly shortened.

  In the present embodiment, in addition to the effects (a) and (b) in the first embodiment, the following effects can be achieved.

  (D) The matrix resin 12 is injected into the bag-like cavity 15 inserted in the mold-opened molding cavity, and diffused onto the reinforcing fiber layer 10 in the molding cavity from the numerous holes provided in the bag-like cavity 15. The matrix resin 12 having a set filling amount can be injected into the mold 1 in a short time in a state where the matrix resin 12 is widely adhered to the reinforcing fiber layer 10. Further, by closing the upper mold 2, the matrix resin 12 in the bag-shaped cavity 15 is spread over the entire molding cavity surface 2 A, and the reinforcing fiber layer 10 is generally reinforced from the countless small holes of the bag-shaped cavity 15. The layer 10 can be impregnated in the thickness direction, and the molding time can be greatly shortened.

(Third embodiment)
FIG. 7 shows a third embodiment of an RTM molding apparatus and an RTM molding method to which the present invention is applied. FIG. 7A is a sectional view of the RTM molding apparatus, and FIGS. 7B to 7D are RTM molding processes. FIG. In the present embodiment, the molding time is shortened by injecting a matrix resin with a nozzle before starting the closing of the mold. The same devices as those in FIGS. 1 to 6 are denoted by the same reference numerals, and the description thereof is omitted or simplified.

  The RTM molding apparatus of this embodiment is almost the same as the RTM molding apparatus of the first embodiment, but the resin injection port 5 provided in the upper mold 2 is omitted, and a nozzle for injecting the matrix resin 12 instead. 16 is provided separately. The nozzle 16 includes a plurality of injection holes for the matrix resin 12 and has a structure that can move laterally on the molding cavity surface 3 </ b> A of the lower mold 3.

  The RTM molding process by the RTM molding apparatus having the above configuration will be described below.

  FIG. 7A shows a set state of the fiber reinforced layer 10. The reinforced fiber layer 10 is put into the lower mold 3 in the mold 1 that has been opened and placed on the cavity surface 3 A of the lower mold 3. Next, the nozzle 16 provided with the resin injection port is moved onto the lower mold 3, and a predetermined amount of the thermosetting resin 12 calculated from the reinforcing fiber content in advance is injected from the nozzle 16 onto the fiber reinforced layer 10. At this time, the nozzle 16 is controlled to move laterally so that the matrix resin 12 covers almost the entire area of the reinforcing fiber layer 10. The matrix resin 12 adheres to the surface of the reinforcing fiber layer 10, and the matrix resin 12 that has not been attached accumulates here because the central portion of the upper surface of the reinforcing fiber layer 10 is low.

  When the matrix resin 12 has been injected, the nozzle 16 is withdrawn from the mold, the mold closing is started, the air suction device 8 is operated in parallel, and the air in the molding cavity in the molding die 1 is sucked into the suction port 7. Start aspiration via.

  When the seal surface 2B of the upper mold 2 comes into contact with the hermetic seal 11, the space of the molding cavity and the outside air are blocked, and the surface of the reinforcing fiber layer 10 placed on the lower mold 3 cavity surface 3A and the upper mold 2 cavity surface 2A. There is a gap corresponding to the dimension (for example, 5 mm) that the seal seal 11 protrudes from the seal housing groove 3B (see FIG. 7B). The matrix resin 12 spreads again in the molding cavity as the distance between the reinforcing fiber layer 10 and the upper mold 2 becomes smaller, and the distance between the surface of the reinforcing fiber layer 10 and the upper mold 2 cavity surface 2A is the volume of the resin amount. When almost equal, the matrix resin 12 spreads over the entire surface of the molding cavity.

  Further, when the molding die 1 is closed, as in the first embodiment, since the inside of the molding cavity is in a substantially vacuum state, the matrix resin 12 is impregnated into the fiber layer 10 and is completely closed. Then, as shown in FIG. 7C, the entire reinforcing fiber layer 10 is impregnated.

  Thereafter, as in the first embodiment, the molding cavity of the molding die 1 is heated, the thermosetting resin 12 in the molding cavity is cured, and FRP is formed by combining the reinforcing fiber layer 10 and the thermosetting resin 12. The When the curing of the resin 12 is finished, the mold 1 is opened and the FRP product W is taken out, as shown in FIG.

  According to the RTM molding apparatus and the RTM molding method described above, the filling amount of the matrix resin 12 set by injecting the matrix resin 12 onto the reinforcing fiber layer 10 from the injection nozzle 16 is quickly injected into the mold 1. can do. Then, by closing the mold, the matrix resin 12 in the gap between the reinforcing fiber layer 10 and the upper mold 2 molding cavity surface 2A can be spread over the entire molding cavity and impregnated in the thickness direction of the reinforcing fiber layer 10 in the entire molding cavity. The molding time can be greatly shortened.

  In the present embodiment, in addition to the effects (a) and (b) in the first embodiment, the following effects can be achieved.

  (E) Since the matrix resin 12 is injected by the injection nozzle 16 so as to adhere to the upper surface of the reinforcing fiber layer 10 put into the mold 1 that has been opened, the set amount of the matrix resin 12 of the reinforcing fiber layer 10 It can be injected into the mold 1 in a short time while being attached to the entire surface. For this reason, the molding time can be greatly shortened.

(Fourth embodiment)
FIG. 8 shows a fourth embodiment of an RTM molding device and an RTM molding method to which the present invention is applied. FIG. 8A is a cross-sectional view of the RTM molding device, and FIGS. 8B to 8D are RTM molding steps. FIG. In the present embodiment, the molding time is shortened by injecting a matrix resin with a nozzle before feeding the reinforcing fiber layer into the mold. 1 to 7 are denoted by the same reference numerals, and description thereof is omitted or simplified.

  The RTM molding apparatus of this embodiment is almost the same as the RTM molding apparatus of the first embodiment, but the resin injection port 5 provided in the upper mold 2 is omitted, and a nozzle for injecting the matrix resin 12 instead. 17 is provided separately. In the illustrated example, the matrix resin 12 has one injection port, but a plurality of nozzles 17 having a plurality of injection ports or one injection port may be provided.

  The RTM molding process by the RTM molding apparatus having the above configuration will be described below.

  FIG. 8A shows a fiber reinforced layer set state. First, a predetermined amount of thermosetting resin 12 calculated from the fiber content is injected into the lower mold 3 in the mold 1 that has been opened. At this time, the nozzle 17 is configured to match the shape of the molding cavity surface 3A so that the matrix resin 12 is placed on almost the entire lower mold 3 cavity surface 3A. The matrix resin 12 adheres to the lower mold 3 cavity surface 3A, and the matrix resin 12 that has not been adhered accumulates here because the central portion of the lower mold 3 cavity surface 3A is low. When the matrix resin 12 has been injected, the nozzle 17 is retracted from the mold, and then the reinforcing fiber layer 10 corresponding to the product plate thickness is placed on the matrix resin 12. At this time, in order to completely suck the air in the mold 1, it is preferable that a peel ply 18 (peeling layer) or the like is stacked on the uppermost layer of the reinforcing fiber layer 10. The injected reinforcing fiber layer 10 is in a state of floating on the matrix resin 12 accumulated in the center of the lower mold 3 cavity surface 3A.

  The mold closing is started, the air suction device 8 is operated in parallel, and the air in the molding cavity in the mold 1 is started to be sucked through the suction port 7. The upper mold 2 cavity surface 2A and the upper surface of the reinforcing fiber layer 10 come into contact with each other, and the matrix resin 12 accumulated between the lower surface of the reinforcing fiber layer 10 and the lower mold 3 cavity surface 3A is expanded. When the seal surface 2B of the upper mold 2 comes into contact with the hermetic seal 11, the space of the molding cavity and the outside air are blocked, and the hermetic seal 11 seals between the lower mold 3 cavity surface 3A and the lower surface of the reinforcing fiber layer 10. There is a gap corresponding to the dimension protruding from the housing groove 3B (for example, 5 mm) (see FIG. 8B). The matrix resin 12 expands in the molding cavity as the distance between the reinforcing fiber layer 10 and the lower mold 3 becomes smaller, and the distance between the surface of the reinforcing fiber layer 10 and the lower mold 3 cavity surface 3A is substantially equal to the volume of the resin amount. At the same time, the matrix resin 12 is spread over the entire surface of the molding cavity.

  Further, as the mold 1 is closed, the inside of the mold cavity is almost in a vacuum state, so that the matrix resin 12 is impregnated into the fiber layer 10 from the lower surface and the mold is completely closed in FIG. ), The entire reinforcing fiber layer 10 is impregnated.

  Thereafter, as in the first embodiment, the molding cavity of the molding die 1 is heated, the thermosetting resin 12 in the molding cavity is cured, and FRP is formed by combining the reinforcing fiber layer 10 and the thermosetting resin 12. The When the curing of the resin 12 is finished, as shown in FIG. 8D, the mold 1 is opened and the FRP product W is taken out.

  According to the RTM molding apparatus and the RTM molding method described above, the matrix of the filling amount set by injecting the matrix resin 12 from the injection nozzle 17 onto the lower mold 3 cavity surface 3A before the reinforcing fiber layer 10 is arranged. The resin 12 can be injected into the mold in a short time. Then, the reinforcing fiber layer 10 is placed on the matrix resin 12 and the upper mold 2 is closed to spread the matrix resin 12 in the gap between the reinforcing fiber layer 10 and the lower mold 3 cavity surface 3A over the entire molding cavity surface 3A. Furthermore, the entire molding cavity surface 3A can be impregnated in the thickness direction of the reinforcing fiber layer 10, and the molding time can be greatly shortened.

  In the present embodiment, in addition to the effects (a) and (b) in the first embodiment, the following effects can be achieved.

  (F) The matrix resin 12 is injected by the injection nozzle 17 so as to adhere to the lower mold 3 cavity surface 3A of the mold 1 that has been opened before the reinforcing fiber layer 10 is charged. While being attached to the entire surface of the lower mold 3 cavity surface 3A, it can be poured into the mold 1 in a short time, and the matrix resin 12 can be impregnated into the reinforcing fiber layer 10 from the lower surface, so that more uniform impregnation can be achieved. Therefore, the molding time can be greatly shortened.

  In the above embodiment, the case where the seal receiving groove 3B is shallower than the diameter of the hermetic seal 11 has been described as an example in which the molding cavity is shut off from the outside air in the mold closing process. It may protrude elastically by an amount set from the mold.

Sectional drawing of the RTM shaping | molding apparatus which shows one Embodiment of this invention. The process figure which divides and shows the RTM shaping | molding process similarly to (A)-(C). The fragmentary sectional view which shows the flow state of the injection | pouring resin at the time of resin injection | pouring. The fragmentary sectional view which shows the resin flow state at the time of mold closing. The fragmentary sectional view which shows the resin flow state in the past. Sectional drawing which divides and shows the RTM shaping | molding apparatus and RTM shaping | molding method which show 2nd Embodiment of this invention into (A)-(D). Sectional drawing which divides and shows the RTM shaping | molding apparatus and RTM shaping | molding method which show 3rd Embodiment of this invention into (A)-(D). Sectional drawing which divides and shows the RTM shaping | molding apparatus and RTM shaping | molding method which show 4th Embodiment of this invention into (A)-(D).

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Mold 2 Upper mold 3 Lower mold 4 On-off valve 5 Inlet 6 Resin injection device 7 Suction port 8 Suction device 9 Mold temperature control pipe 10 Reinforcement fiber layer 11 Sealing seal 12 Matrix resin, thermosetting resin 15 Bag-like cavity 16 , 17 nozzles

Claims (7)

It is a resin transfer molding method in which a reinforcing fiber layer disposed in a molding cavity of a molding die is impregnated with a matrix resin and heat-cured.
Insert a reinforcing fiber layer and a matrix resin between the molds in an open state,
The matrix resin is spread on the surface of the reinforcing fiber layer in the molding cavity according to the mold closing,
A resin transfer molding method comprising impregnating a reinforcing fiber layer with a matrix resin developed by subsequent mold closing.   2. The resin transfer molding method according to claim 1, wherein when the matrix resin is unfolded, the molding cavity is blocked from outside air to be in a negative pressure state.   3. The resin transfer molding method according to claim 1, wherein the matrix resin is injected as a negative pressure state by blocking a molding cavity of the molding die in the middle of mold closing from outside air. 4.   The matrix resin is injected into a bag-like cavity inserted into a molding cavity of a mold that has been opened, and from the infinite number of holes provided in the bag-like cavity, between the mold open state and the mold closed state, The resin transfer molding method according to claim 1, wherein the resin transfer molding is diffused on the reinforcing fiber layer.   3. The resin transfer molding method according to claim 1, wherein the matrix resin is injected by an injection nozzle so that the matrix resin adheres to an upper surface of a reinforcing fiber layer put into a mold that is opened.   The resin transfer molding according to claim 1 or 2, wherein the matrix resin is injected by an injection nozzle so as to adhere to a lower mold cavity surface of the mold that has been opened before the reinforcing fiber layer is charged. Method. It is a resin transfer molding molding device that impregnates a matrix resin into a reinforcing fiber layer disposed in a molding cavity of a molding die and heat cures it.
Means for injecting a matrix resin between the molds in an open state;
Means for blocking the molding cavity from the outside air during mold closing;
A resin transfer molding apparatus comprising: a means for setting the inside of the molding cavity to a negative pressure state while the outside air is shut off.

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