Injection molding device and injection molding method for fiber-reinforced resin

Abstract

Provided is an injection molding device for a fiber-reinforced resin, comprising: a heating cylinder for melting a resin; a screw inserted through the heating cylinder; a resin feeding unit that feeds the resin into the heating cylinder; a long fiber feeding unit for feeding long fibers into the heating cylinder; and an auxiliary unit that assists the contact between the resin melted in the heating cylinder and the long fibers introduced into the heating cylinder.

Description

Technical Field

[0001] The present invention relates to an injection molding device and a method for injection molding of a fiber reinforced resin. Background Art

[0002] Conventionally, there is known a direct injection molding machine that does not melt-knead the resin and the filaments in advance, but directly puts the resin and the filaments into a heating cylinder (heating barrel), melts and kneads them, and then performs injection molding.

[0003] Patent document 1 describes a manufacturing device for fiber-reinforced resin molded products, which includes: a heating cylinder; a screw inserted into the inner side of the heating cylinder; an injection portion provided at the front end side of the screw; a resin input portion for injecting matrix resin into the inner side of the heating cylinder; a long fiber input portion for injecting long fibers into the inner side of the heating cylinder; and a short fiber input portion for injecting short fibers shorter than long fibers into the inner side of the heating cylinder. Here, in the manufacturing device for fiber-reinforced resin molded products, the short fiber input portion is closer to the rear end of the screw than the long fiber input portion.

[0004] [Prior Technical Literature]

[0005] (Patent Document)

[0006] Patent Document 1: Japanese Patent Application Publication No. 2022-138851 Summary of the invention

[0007] [Problems to be solved by the invention]

[0008] However, in the manufacturing apparatus of the fiber-reinforced resin molded product described in Patent Document 1, it is difficult for a plurality of long fibers to contact the resin melted in the heating cylinder, which may cause a decrease in productivity and an increase in waste materials.

[0009] An object of the present invention is to provide a fiber-reinforced resin injection molding device and a fiber-reinforced resin injection molding method that can improve productivity and reduce waste materials.

[0010] [Technical means to solve the problem]

[0011] (1) A fiber-reinforced resin injection molding device, comprising: a heating cylinder for melting resin; a screw inserted into the heating cylinder; a resin feeding section for feeding the resin into the heating cylinder; a long fiber feeding section for feeding long fibers into the heating cylinder; and an auxiliary section for assisting the contact between the resin melted in the heating cylinder and the long fibers fed into the heating cylinder.

[0012] (2) The fiber-reinforced resin injection molding device according to (1), wherein the long-fiber input portion is provided on the downstream side of the resin input portion.

[0013] (3) The fiber-reinforced resin injection molding device according to (1) or (2), wherein the long-fiber feeding section feeds a plurality of the long fibers into the heating cylinder.

[0014] (4) The fiber-reinforced resin injection molding device according to (3), wherein the auxiliary unit sprays the adhesive in an atomized form onto the plurality of long fibers introduced into the heating cylinder.

[0015] (5) The fiber-reinforced resin injection molding device according to (3), wherein the auxiliary unit sprays hot melt adhesive onto a portion of the plurality of long fibers introduced into the heating cylinder.

[0016] (6) The fiber-reinforced resin injection molding device according to any one of (1) to (3), wherein the auxiliary unit blows compressed air toward the long fibers introduced into the heating cylinder.

[0017] (7) The fiber-reinforced resin injection molding device according to any one of (1) to (3), wherein the auxiliary portion guides the long fibers fed into the heating cylinder using a guide plate.

[0018] (8) The fiber-reinforced resin injection molding device according to any one of (1) to (3), wherein the auxiliary portion sucks the long fibers to assist the long fibers in contact with the resin melted in the heating cylinder.

[0019] (9) The fiber-reinforced resin injection molding device according to any one of (1) to (3), wherein the long-fiber input portion is provided with a rod-shaped member capable of loading and unloading the long fibers.

[0020] The auxiliary section moves the rod-shaped member to which the long fibers are attached, and assists the contact between the rod-shaped member and the resin melted in the heating cylinder.

[0021] (10) The fiber-reinforced resin injection molding device according to any one of (1) to (9), wherein a conveying member for conveying the long fibers is provided in the long-fiber input portion.

[0022] (11) A method for injection molding of fiber-reinforced resin, comprising the following steps: injecting and melting resin into a heating cylinder having a screw inserted therethrough; injecting long fibers into the aforementioned heating cylinder; and assisting contact between the resin melted in the aforementioned heating cylinder and the long fibers injected into the aforementioned heating cylinder.

[0023] (Effects of the Invention)

[0024] According to the present invention, a fiber-reinforced resin injection molding apparatus and a fiber-reinforced resin injection molding method can be provided, which can improve productivity and reduce waste materials. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] Figure 1 This is a schematic diagram showing an example of a fiber-reinforced resin injection molding apparatus according to the present embodiment.

[0026] Figure 2 yes Figure 1 A partially enlarged cross-sectional view of a fiber-reinforced resin injection molding device.

[0027] Figure 3 Yes Description Figure 2 A cross-sectional view showing the function of the adhesive spray section.

[0028] Figure 4 Yes Description Figure 2 A cross-sectional view showing the function of the adhesive spray section.

[0029] Figure 5 yes Figure 1 A partially enlarged cross-sectional view of a variation of an injection molding apparatus for fiber-reinforced resin.

[0030] Figure 6 Yes Description Figure 5 A cross-sectional view of the function of the hot melt adhesive ejection unit.

[0031] Figure 7 Yes Description Figure 5 A cross-sectional view of the function of the hot melt adhesive ejection unit.

[0032] Figure 8 Yes Description Figure 5 A cross-sectional view of the function of the hot melt adhesive ejection unit.

[0033] Fig. 9 yes Figure 1 A partially enlarged cross-sectional view of a variation of an injection molding apparatus for fiber-reinforced resin.

[0034] Fig.10 yes Figure 1 A partially enlarged cross-sectional view of a variation of an injection molding apparatus for fiber-reinforced resin.

[0035] Fig.11 yes Fig.10 A partially enlarged cross-sectional view of a variation of an injection molding apparatus for fiber-reinforced resin.

[0036] Fig.12 yes Figure 1 A partially enlarged cross-sectional view of a variation of an injection molding apparatus for fiber-reinforced resin.

[0037] Fig.13 yes Fig.12 A partially enlarged cross-sectional view of a variation of an injection molding apparatus for fiber-reinforced resin. DETAILED DESCRIPTION

[0038] Hereinafter, embodiments of the present invention will be described with reference to the drawings.

[0039] [Injection molding equipment for fiber-reinforced resin]

[0040] exist Figure 1 2 , an injection molding machine 10 is shown as an example of a fiber-reinforced resin injection molding apparatus according to the present embodiment.

[0041] The injection molding machine 10 is a direct injection molding machine, and includes a heating cylinder 11 for melting resin, and a screw 12 inserted into the heating cylinder 11. The heating cylinder 11 is provided with: a hopper 13A, which is a resin input part for inputting resin into the heating cylinder 11; and a drop box 13B, which is a long fiber input part for inputting a plurality of long fibers into the heating cylinder 11. Here, the resin melted in the heating cylinder 11 is transported from the upstream side to the downstream side of the heating cylinder 11 by the rotation of the screw 12. In addition, the drop box 13B is provided on the downstream side of the hopper 13A, but as long as the long fibers input into the heating cylinder 11 can be brought into contact with the resin melted in the heating cylinder 11, the drop box 13B may not be provided on the downstream side of the hopper 13A. In addition, a single long fiber may be input from the drop box 13B. Furthermore, short fibers may be input together with the resin from the hopper 13A.

[0042] In addition, the injection molding machine 10 is further provided with: a nozzle (injection port) 14 for injecting the molten kneaded product (fiber reinforced resin) generated in the heating cylinder 11; and a mold 15 for molding the molten kneaded product injected from the nozzle 14. Here, the vicinity of the nozzle 14 of the heating cylinder 11 is formed into a substantially conical area capable of accommodating the front end of the screw 12. The mold 15 is composed of a fixed mold and a movable mold.

[0043] like Figure 2 As shown, in the injection molding machine 10, an adhesive spraying section 21 is provided on the top surface of the drop box 13B, and the adhesive spraying section 21 is an auxiliary section that assists the contact between the molten resin M melted in the heating cylinder 11 and the long fibers L dropped into the heating cylinder 11. The adhesive spraying section 21 sprays the adhesive A in an atomized form toward the long fibers L. As a commercially available product of the adhesive spraying section 21, for example, an automatic spray gun SGA-3 series (manufactured by ANESTIWATA) can be cited.

[0044] The injection molding machine 10 is provided with a plurality of tubes 22, which guide a plurality of long fibers L extracted from a plurality of rovings R to a drop box 13B, and an adhesive spraying section 21 is arranged between adjacent tubes 22 of the drop box 13B. At this time, compressed air supply sections 23 and 24 are provided on the upstream and downstream sides of the plurality of tubes 22. The compressed air supply sections 23 and 24 are conveying components for supplying compressed air to convey the long fibers L vertically upward and vertically downward, respectively. As commercially available products of the compressed air supply sections 23 and 24, for example, a vacuum blow dual-purpose valve (Vacuum Flow) (manufactured by SMC) can be cited.

[0045] If Figure 3 As shown in FIG. 1 , the adhesive spraying unit 21 sprays the adhesive A in the form of atomized sprays toward the plurality of long fibers L put into the heating cylinder 11, thereby imparting adhesiveness to the surface of the long fibers L. As a result, Figure 4 As shown, after being bonded, the plurality of long fibers L come into contact with the molten resin M adhering to the screw 12 , and as a result, are wound around the screw 12 .

[0046] If the injection molding machine 10 is not provided with the adhesive spraying unit 21 , it becomes difficult for the plurality of long fibers L to come into contact with the molten resin M adhering to the screw 12 , which may cause a decrease in productivity and an increase in waste materials.

[0047] In addition, in the injection molding machine 10, when the compressed air supply unit 24 is not provided on the downstream side of the plurality of tubes 22, for example, after the rotation of the screw 12 is temporarily stopped and the plurality of long fibers L are manually fed into the heating cylinder 11, the rotation of the screw 12 is restarted to wind the plurality of long fibers L around the screw 12. In this case, manual work needs to be repeated until all the long fibers L fed into the heating cylinder 11 are wound around the screw 12, resulting in a decrease in productivity and an increase in waste materials.

[0048] The adhesive A is not particularly limited as long as it can be sprayed onto the long fibers L and can impart adhesiveness to the surface of the long fibers L. Commercially available products of the adhesive A include, for example, Super G Spray Z (manufactured by KONISHI Industries) and RQ-NVN2 (manufactured by AICA Industries).

[0049] The resin constituting the molten resin M is not particularly limited, and an example thereof includes polyimide.

[0050] The fibers constituting the long fibers L and the short fibers are not particularly limited, and examples thereof include glass fibers, carbon fibers, and aramid fibers.

[0051] Furthermore, the fibers constituting the long fibers L and the short fibers may be the same or different.

[0052] In the injection molding machine 10, the adhesive spraying unit 21 may be provided on the top surface of the drop box 13B, or a hot melt adhesive ejecting unit 51 may be provided on the side surface of the drop box 13B on the upstream side relative to the rotation direction of the screw 12 (see Figure 5 The hot melt adhesive ejection unit 51 ejects the hot melt adhesive H toward a portion of the plurality of long fibers L. At this time, as a commercially available product of the hot melt adhesive ejection unit 51, for example, an electric hot melt glue gun TE-m12 (manufactured by Sanyo-Life Material) can be cited.

[0053] When Figure 6 As shown in FIG. 1 , when the hot melt adhesive ejection unit 51 ejects the hot melt adhesive H at an ejection angle α toward a portion of the plurality of long fibers L introduced into the heating cylinder 11, as shown in FIG. Figure 7 As shown in FIG. 1 , the long fibers L bonded by the hot melt adhesive H come into contact with the molten resin M attached to the screw 12, and as a result, begin to be wound around the screw 12. Figure 8 As shown, the remaining part of the long fibers L is guided so as to come into contact with the molten resin M adhering to the screw 12 by the long fibers L that have started to be wound around the screw 12 , and as a result, a plurality of long fibers L are wound around the screw 12 .

[0054] The material constituting the hot melt adhesive H is not particularly limited as long as it can adhere to a part of the long fibers L, and examples thereof include polyamide, polyolefin, ethylene vinyl acetate copolymer, and acrylic resin.

[0055] The viscosity of the hot melt adhesive H is not particularly limited as long as it can be ejected onto a portion of the long fibers L, and is, for example, 1000 cps or more and 17000 cps or less.

[0056] The blowing angle α is not particularly limited as long as a part of the long fibers L can be bonded, and is, for example, 25° or more and 45° or less.

[0057] In the injection molding machine 10, the adhesive spraying section 21 may be provided on the top surface of the drop box 13B, or a compressed air ejecting section 91 may be provided on the side surface of the drop box 13B on the upstream side relative to the rotation direction of the screw 12 (see Fig. 9 The compressed air ejection unit 91 ejects the compressed air C toward the plurality of long fibers L. At this time, as a commercially available product of the compressed air ejection unit 91, for example, a rechargeable air duster AS001GZ (manufactured by Makita) can be cited.

[0058] When the compressed air ejection unit 91 ejects compressed air C at an ejection angle β toward the plurality of long fibers L introduced into the heating cylinder 11 , the plurality of long fibers L are guided by the compressed air C so as to come into contact with the molten resin M attached to the screw 12 , and as a result, are wound around the screw 12 .

[0059] The ejection angle β is not particularly limited as long as the plurality of long fibers L can come into contact with the molten resin M, and is, for example, 25° or more and 45° or less.

[0060] In the injection molding machine 10, the adhesive spraying section 21 may be provided on the top surface of the drop box 13B, or a guide plate 101 may be provided at an inclined angle γ on the side surface of the drop box 13B on the upstream side relative to the rotation direction of the screw 12 (see FIG. Fig.10 ). The guide plate 101 guides the plurality of long fibers L. As the guide plate 101, a movable guide plate that can move in an inclined direction may be used.

[0061] When a plurality of long fibers L are introduced into the heating cylinder 11 , the plurality of long fibers L are guided by the guide plate 101 so as to come into contact with the molten resin M adhering to the screw 12 , and as a result, are wound around the screw 12 .

[0062] The inclination angle γ is not particularly limited as long as the plurality of long fibers L can come into contact with the molten resin M, and is, for example, 15° or more and 45° or less.

[0063] exist Fig.10 In the embodiment, an electric rotating roller 111 may be provided to replace the compressed air supply unit 24 (see Fig.11 ). The electric rotating roller 111 is a conveying member that conveys the long fibers L vertically downward by rotating. Fig.10 The injection molding machine 10 other than the above uses the electric rotary roller 111 .

[0064] In the injection molding machine 10, the compressed air supply unit 24 may not be provided, and the input box 13B may be provided on the heating cylinder 11. Alternatively, the input port 121 may be formed, and a suction unit 122 may be provided on the heating cylinder 11 to assist the contact between the molten resin in the heating cylinder 11 and the long fibers L input into the heating cylinder 11 (see Fig.12 ). In the suction section 122, a suction path 122a is formed on the downstream side of the heating cylinder 11 relative to the inlet 121, and suction is performed by the suction pump 122b. At this time, the suction path 122a is sucked vertically upward, and the inlet 121 is sucked vertically downward. Therefore, the plurality of long fibers L are sucked from the inlet 121 toward the suction path 122a in the space between the heating cylinder 11 and the screw 12, and thus come into contact with the molten resin M attached to the screw 12.

[0065] exist Fig.12 In the embodiment, the heating cylinder 11 may be provided with a suction unit 122, or a rod-shaped member 131 capable of loading and unloading the long fibers L may be provided at the input port 121 instead (see Fig.13 ). The rod-shaped member 131 is supported by the supporting member 132 and can be moved in the vertical direction by, for example, a motor. At this time, when the rod-shaped member 131 with the long fibers L mounted thereon is moved vertically downward, it comes into contact with the molten resin M attached to the screw 12. On the other hand, when the rod-shaped member 131 is moved vertically upward, the long fibers that come into contact with the molten resin M are removed from the rod-shaped member 131.

[0066] The rod-shaped member 131 is not particularly limited as long as the long fibers L can be attached and detached. For example, a heat-resistant rubber may be provided at the tip end, or a recess may be formed at the tip end.

[0067] [Injection molding method of fiber-reinforced resin]

[0068] The fiber-reinforced resin injection molding method of the present embodiment includes the following steps: injecting and melting a resin into a heating cylinder having a screw inserted therein; injecting long fibers into the heating cylinder; and assisting the contact between the resin melted in the heating cylinder and the long fibers injected into the heating cylinder. Here, the fiber-reinforced resin injection molding method of the present embodiment can be implemented using the fiber-reinforced resin injection molding device of the present embodiment.

[0069] The above is a description of the embodiments of the present invention, but the present invention is not limited to the above embodiments, and the above embodiments may be appropriately modified within the scope of the present invention. For example, any one of the adhesive spraying unit 21, the hot melt adhesive ejecting unit 51, the compressed air ejecting unit 91, and the guide plate 101 may be used in combination.

[0070] Reference numerals

[0071] 10Injection molding machine

[0072] 11 Heating cylinder

[0073] 12 screw

[0074] 13A Hopper

[0075] 13B drop box

[0076] 14 Nozzles

[0077] 15 Mould

[0078] 21 Adhesive spraying department

[0079] 22 tubes

[0080] 23, 24 Compressed air supply unit

[0081] 51 Hot melt adhesive dispensing unit

[0082] 91 Compressed air ejection unit

[0083] 101 guide plate

[0084] 111 Electric rotating roller

[0085] 121 Input

[0086] 122 Suction Department

[0087] 121a Suction path

[0088] 121c Suction Pump

[0089] 131 Rod-shaped parts

[0090] 132 Supporting parts

[0091] A Adhesive

[0092] Compressed air

[0093] H Hot Melt Adhesive

[0094] L long fiber

[0095] M Molten Resin

[0096] R roving

Claims

1. A fiber-reinforced resin injection molding device comprising: Heating the cylinder to melt the resin; A screw rod is inserted into the aforementioned heating cylinder; A resin feeding part, feeding the resin into the heating cylinder; A long fiber input unit inputs long fibers into the heating cylinder; and The auxiliary part assists the contact between the resin melted in the heating cylinder and the long fibers introduced into the heating cylinder.

2. The fiber-reinforced resin injection molding device according to claim 1, wherein: The long-fiber input portion is provided on the downstream side of the resin input portion.

3. The fiber-reinforced resin injection molding device according to claim 1 or 2, wherein: The long-fiber input section inputs a plurality of the long fibers into the heating cylinder.

4. The fiber-reinforced resin injection molding device according to claim 3, wherein: The auxiliary part sprays the adhesive in the form of atomization toward the plurality of long fibers put into the heating cylinder.

5. The fiber-reinforced resin injection molding device according to claim 3, wherein: The auxiliary part sprays hot melt adhesive onto a part of the plurality of long fibers introduced into the heating cylinder.

6. The fiber-reinforced resin injection molding device according to claim 1 or 2, wherein: The auxiliary part blows compressed air toward the long fibers put into the heating cylinder.

7. The fiber-reinforced resin injection molding device according to claim 1 or 2, wherein: The auxiliary part guides the long fibers put into the heating cylinder by means of a guide plate.

8. The fiber-reinforced resin injection molding device according to claim 1 or 2, wherein: The auxiliary portion sucks the long fibers to assist the long fibers in contact with the resin melted in the heating cylinder.

9. The fiber-reinforced resin injection molding device according to claim 1 or 2, wherein: The long fiber input section is provided with a rod-shaped member capable of loading and unloading the long fibers. The auxiliary section moves the rod-shaped member to which the long fibers are attached, and assists the contact between the rod-shaped member and the resin melted in the heating cylinder.

10. The fiber-reinforced resin injection molding device according to claim 1 or 2, wherein: The long-fiber input portion is provided with a conveying member for conveying the long-fibers.

11. A method for injection molding of a fiber-reinforced resin, comprising the following steps: The resin is poured into a heating cylinder with a screw inserted therein and melted; Adding long fibers into the aforementioned heating cylinder; and, The contact between the resin melted in the heating cylinder and the long fibers introduced into the heating cylinder is assisted.

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