KR100831289B1 - Forming mold for reinforced plastics and forming method for reinforced plastics - Google Patents

Abstract

A forming mold and a method for manufacturing reinforced plastics are provided to prevent air bubbles from being generated in the plastics by forming the forming mold into a vacuum state. A forming mold comprises a sealing part(40) and a vacuum part(60). The sealing part is installed at a portion, in which an upper mold(10) and a lower mold(12) are in contact with each other, to prevent air from flowing into an inner space(20) between the upper mold and the lower mold. The vacuum part draws in air contained in the inner space, which is sealed by the sealing part, to the outside. The vacuum part includes a pipe member(64), which has a pipe disposed in the lower mold, and a pump member(76) connected to the pipe member.

Description

Forming mold for reinforced plastics and forming method for reinforced plastics

1 is in accordance with the prior art Figure shows a mold apparatus for reinforcing plastic molding.

2 is a view showing a state in which the upper mold and the lower mold shown in FIG.

Figure 3 is a side cross-sectional view showing a mold apparatus for reinforcing plastic molding according to an embodiment of the present invention.

4 is a view showing a state before the upper mold and the lower mold shown in FIG.

FIG. 5 is an enlarged view of a portion “A” of FIG. 3.

FIG. 6 is an exploded view illustrating the sealing part illustrated in FIG. 5.

7 is a view showing the main configuration of the vacuum portion of the mold apparatus for reinforcing plastic molding according to an embodiment of the present invention.

<Description of Symbols for Main Parts of Drawings>

10: upper mold 11: outer wear plate

12: lower mold 13: inner wear plate

14: support jaw 20: inner space

30: reinforcing fiber 40: sealing part

42: airtight member 44: head member

45: locking jaw 46: body member

48: corner 49: free space

50: mounting bracket 52: tightening screw

60: vacuum portion 62: upper through hole

64: pipe member 66: lower side through-hole

68: mounting plate 70: check valve

72: outer pipe 74: pressure sensor

76 pump member 78 control unit

The present invention relates to a reinforced plastic, and more particularly, a mold apparatus for reinforced plastic molding and a method of forming a reinforced plastic molding by applying a vacuum molding method to a mold for molding a reinforced plastic by a sheet molding compound (hereinafter referred to as SMC) method. It is about.

Recently, reinforcement plastics are widely used in the structure of the vehicle as part of the weight reduction of the vehicle. Since reinforcement plastics are lighter than metal materials, the reinforcement plastics are used to help improve fuel efficiency, especially in the performance of sports cars. Crazy

Reinforced plastics are made by mixing plastics with various reinforcing materials, such as glass or carbon fiber, to compensate for the inferior mechanical properties such as strength, stiffness and creep resistance of plastics compared to metals and alloys.

The reinforcing material improves the mechanical properties of the plastic and increases the strength and rigidity to the weight. Reinforced plastics manufactured as described above are increasingly being used in aircraft, automobiles, ships, and sporting goods.

The reinforced plastic is composed of a plastic base material and a reinforcing fiber (or sheet: sheet), and commonly used reinforcing fibers include glass, carbon, aramid, boron, and the like. As it falls, there is little structural value in itself.

The plastic base material has higher strength and stiffness than the reinforcing fiber but has high toughness, and protects the reinforcing fiber from physical damage and the surrounding environment, and suppresses the propagation of cracks generated in the composite material by ductility and toughness. Has

Epoxy, polyester, phenolic resin, carbon fluoride, polysulfide polyether, silicone, etc. are commonly used as materials of the plastic base material. As such, reinforced plastics combine only the advantages of the two components. In addition, it has higher fatigue resistance, toughness and creep resistance than ordinary plastics and is relatively easy to design, manufacture and repair.

Reinforced plastics are unique in structure and use special processing methods to produce useful products. The reinforcing materials used are dispersed fibers, woven fabrics or mats, continuous fibers, and the like, and the reinforcing materials are impregnated into the plastic so as to be firmly bonded to the plastic base material so as to be coated.

Hereinafter, with reference to the accompanying drawings will be described a conventional mold for reinforcing plastic molding.

1 is a view showing a mold for molding a reinforced plastic according to the prior art, Figure 2 is a view showing a state in which the upper mold and the lower mold shown in FIG.

As shown in FIG. 1, an inner space for forming the reinforced plastic 9 is formed between the upper mold 1 and the lower mold 3 to form the reinforced plastic by the sheet molding compound (hereinafter referred to as SMC) method. (5) is provided, the lower mold (3) above the reinforcing fiber (7) is mounted in the state before the preparation for work is completed.

As shown in FIG. 2, the upper mold 1 and the lower mold 3 are combined to supply liquid synthetic resin to the inner space 5 while the inner space 5 is sealed. The reinforcing fiber 7 is cured in a state in which a plastic base material is coated to produce the reinforcing plastic 9.

However, according to the SMC method and the injection molding method as described above, due to the air in the inner space (5) when forming the product, bubbles are present in the reinforced plastic (9) product, the bubbles protrude outwards appearance quality A problem arises, which further requires reworking of the reinforced plastic 9. Therefore, there is a need for improvement.

The present invention has been created by the necessity as described above, the foam is generated in the reinforced plastic by the air in the inner space, the mold apparatus for reinforcing plastic molding to prevent the quality problems and the strength of the product is reduced by the bubble and It is an object of the present invention to provide a molding method of reinforced plastics.

Reinforcing plastic molding mold apparatus according to the present invention is: a reinforcing plastic molding die device is mounted between the upper mold and the lower mold, the liquid plastic resin is supplied to the reinforcing fibers in the reinforcing plastic molding mold apparatus, the upper mold and It is installed on the side that the lower mold is in contact with a sealing portion to block the movement of air to the inner space formed between the upper mold and the lower mold and a vacuum unit for removing the air in the inner space shielded by the sealing portion to the outside It is configured by.

Preferably, the sealing part is provided along an outer surface of the lower mold, and the airtight member is formed of a silicon material.

The sealing part may be formed of a material having elastic force to form a hermetic member having a band shape, and a mounting bracket and the mounting bracket for pressing and fixing the side of the airtight member so that the airtight member is fixed to the outer side of the lower mold. It comprises a fastening screw for fixing to the lower mold.

The airtight member includes a head member protruding out of the mounting bracket to be located between the upper mold and the lower mold, and a body member connected to the head member and fixed between the mounting bracket and the lower mold. .

The vacuum unit includes a conduit member having a conduit formed in the lower mold such that the inner space is connected to an outer side, and a pump member connected to the conduit member to force exhaust of air in the inner space to the outside.

A check valve is provided between the conduit member and the pump member to prevent the back air from flowing back into the inner space.

A pressure sensor is provided between the conduit member and the pump member.

Method for forming a reinforced plastic according to the present invention comprises: mounting a reinforcing fiber on a lower mold to be combined with the upper mold, the upper mold and the lower mold is combined to form an inner space, the air in the inner space Exhausting outwards to form a vacuum state, supplying and molding a liquid synthetic resin to the inner space, and removing the product by demolding after the synthetic resin is solidified.

Preferably, in the step of supplying and molding the synthetic resin, the vacuum pressure of the inner space is measured to maintain the vacuum state set by further exhausting air.

And, the vacuum pressure required in the inner space is characterized in that 0.6 to 0.8 bar.

According to the present invention as described above, the inner space formed between the mold is in a vacuum state to suppress the generation of bubbles in the reinforced plastic to solve the problem of appearance and durability of the reinforced plastic to provide improved productivity than the prior art.

Hereinafter, with reference to the accompanying drawings will be described a preferred embodiment of the mold apparatus for reinforcing plastic molding and the molding method of the reinforced plastic according to the present invention. In this process, the thickness of the lines or the size of the components shown in the drawings may be exaggerated for clarity and convenience of description. In addition, terms to be described below are terms defined in consideration of functions in the present invention, which may vary according to the intention or convention of a user or an operator. Therefore, definitions of these terms should be made based on the contents throughout the specification.

Figure 3 is a side cross-sectional view showing a mold for reinforcing plastic molding according to an embodiment of the present invention, Figure 4 is a view showing a state before the upper mold and the lower mold shown in Figure 3, Figure 5 is an enlarged view of part "A" in FIG. 3, FIG. 6 is an exploded view of the sealing part shown in FIG. 5, and FIG. 7 is a mold apparatus for reinforcing plastic molding according to an exemplary embodiment of the present invention. The main part structure of the vacuum part is shown.

As shown in Figure 3 and 4, the mold apparatus for reinforcing plastic molding according to the present invention is the upper mold 10 and the lower mold to mold the reinforced plastic by the sheet molding compound (SMC) method (hereinafter referred to as SMC) method Between the 12 is provided an inner space 20 for the reinforced plastic molding.

The sealing part 40 is installed on the side of the upper mold 10 and the lower mold 12 in contact with each other to block the movement of air to the inner space 20 formed between the upper mold 10 and the lower mold 12. Done.

The configuration of the sealing unit 40 will be described with reference to FIGS. 5 and 6.

The sealing part 40 allows the inner space 20, which is made when the lower mold 12 and the upper mold 10 to be combined, is sealed to the outside, and various members are used as the sealing part 40 for this purpose. It will be possible.

In addition, the sealing part 40 may be installed in the upper mold 10 at the side in which the upper mold 10 and the lower mold 12 contact, but preferably along the outer surface of the lower mold 12. Is installed.

The sealing part 40 is formed of a material having an elastic force to form a strip-like airtight member 42 and the airtight member 42 of the airtight member 42 such that the airtight member 42 is fixed to an outer surface of the lower mold 12. It comprises a mounting bracket 50 for pressing and fixing the side and a fastening screw 52 for fixing the mounting bracket 50 to the lower mold 12.

The airtight member 42 may be rubber or the like, but the airtight member 42 formed of a silicon material is used to improve durability and airtightness.

The shape of the airtight member 42 is protruded to the outside of the mounting bracket 50 is connected to the head member 44 and the head member 44 located between the upper mold 10 and the lower mold 12 It comprises a body member 46 that is fixed between the mounting bracket 50 and the lower mold 12.

The head member 44 has a supporting jaw 14 formed stepped from the lower mold 12, and the locking jaw 45 is fixed to the upper side (hereinafter referred to in Figure 5) and the lower side is fixed to the mounting bracket 50 The protrusion is formed to form a mushroom head.

The edge 48 of the body member 46 facing the lower mold 12 was chamfered to improve the insertability and fastening property of the airtight member 42.

In addition, the body member 46 forms a free space 49 without contacting the lower mold 12 so that the airtight member 42 is disposed between the lower mold 12 and the side surface of the upper mold 10. When caught in the, the airtight member 42 does not protrude to the outside, one side of the body member 46 is pushed into the free space 49 to prevent the separation of the airtight member 42 do.

In order to prevent the molding of the lower mold 12 from being complicated while supporting the upper side of the airtight member 42, a separate support is formed using the mounting bracket 50 and the fastening screw 52, but the mounting It is another embodiment of the present invention to form the bracket 50 integrally with the lower mold 12.

3 and 4, the lower mold 12 is provided with an inner wear plate 13, and the upper mold 10 corresponding to the upper mold 10 is provided with an outer wear plate 11. When the upper mold 10 and the lower mold 12 are combined, they are brought into contact with each other and fixed.

On the other hand, as shown in Figure 7, the vacuum portion 60 for taking out the air in the inner space 20 shielded by the sealing portion 40 to the upper mold 10 or the lower mold 12 Can be optionally installed in, in the embodiment of the present invention to install a vacuum unit 60 in the lower mold (12).

The vacuum unit 60 is connected to the conduit member 64 and the conduit member 64 having a conduit formed in the lower mold 12 so that the inner space 20 is connected to the outside, and the air in the inner space 20. It comprises a pump member 76 for forcibly exhausting to the outside.

The conduit member 64 is preferably installed in a portion where the inner wear plate 13 is not installed in the lower mold 12. Such a conduit member 64 is formed in the lower mold 12 in the airtight member ( An upper through hole 62 is formed above the 42 and a lower through hole 66 is formed below the airtight member 42.

The mounting plate 68 is installed around the lower through-hole 66 of the pipe member 64 to facilitate the connection of the outer pipe 72 and the connection of the check valve 70, but the mounting plate 68 Omit the above and the outer conduit 72 may be directly connected to the conduit member 64.

Between the conduit member 64 and the pump member 76 to check the check valve 70 to prevent the reverse flow of air to the inner space 20, and for measuring the degree of vacuum of the inner space (20) Pressure sensor 74 is provided.

The pressure measured by the pressure sensor 74 is transmitted to the control unit 78, the control unit 78 to operate the pump member 76 based on this to remove the air in the inner space 20 to the outside Given.

It will be described with respect to the molding method of the reinforced plastic molded by the mold apparatus for reinforcing plastic molding according to an embodiment of the present invention having the configuration as described above.

The molding method of the reinforced plastic according to the present invention has a step of mounting the reinforcing fiber 30 on the lower mold 12 to be combined with the upper mold 10 as shown in FIG.

As shown in FIG. 5, the upper mold 10 and the lower mold 12 are combined to form an inner space 20.

And, by measuring the pressure of the inner space 20 is blocked by the pressure sensor 74 to drive the pump member 76 to the set vacuum pressure to the outside of the air in the inner space (20) To evacuate to form a vacuum state.

Then, a step of forming the reinforced plastic by supplying a synthetic resin of the liquid to the inner space 20 through one side of the upper mold (10).

In the step of supplying and molding the synthetic resin, the vacuum pressure of the inner space 20 may be different from the set vacuum pressure, so that the vacuum member is frequently measured through the pressure sensor 74 to drive the pump member 76. As a result, the air is further exhausted from the inner space 20 so that the inner space 20 is maintained in a set vacuum state.

Then, after the synthetic resin is solidified, it has a step of demolding to take out the product which is reinforced plastic.

The vacuum pressure of the inner space 20 is characterized in that the vacuum pressure required in the inner space 20 is 0.6 to 0.8 bar in order to facilitate the flow of the synthetic resin while preventing the generation of bubbles in the molded product.

According to the configuration as described above, in the present invention, the inner space 20 formed between the upper mold 10 and the lower mold 12 is blocked from the outside by the sealing portion 40, the vacuum portion 60 By the inner space 20 is a vacuum state by suppressing the generation of bubbles in the reinforced plastic to solve the problem of appearance and durability problems to provide improved productivity than the prior art.

Although the present invention has been described with reference to the embodiments shown in the drawings, this is merely exemplary, and those skilled in the art to which the art belongs can make various modifications and other equivalent embodiments therefrom. Will understand.

In addition, the molding apparatus for reinforcing plastic molding and the molding method of the reinforced plastic according to the present invention can be applied not only to the molding by the SMC method but also to the injection molding process.

Therefore, the true technical protection scope of the present invention will be defined by the claims below.

As described above, the reinforcing plastic molding mold apparatus and the molding method of the reinforced plastic according to the present invention, unlike the prior invention in molding the reinforced plastic by the SMC method or injection molding method, the inner side for forming the reinforced plastic By making the space in a vacuum state, air bubbles are prevented from being formed in the reinforcement plastic, and thus quality problems and the strength of the product can be prevented from being lowered.

Claims (11)

In the mold for reinforcing plastic molding is mounted between the upper mold and the lower mold, the reinforcing plastic molding liquid is supplied to the reinforcing fiber is reinforced with a synthetic resin, A sealing part installed on a side of the upper mold and the lower mold to block movement of air to an inner space formed between the upper mold and the lower mold; And It includes a vacuum for extracting the air in the inner space shielded by the sealing to the outside, The vacuum unit may include a conduit member having a conduit formed in the lower mold such that the inner space is connected to the outer side; And And a pump member connected to the pipe member to forcibly exhaust the air in the inner space to the outside. The method of claim 1, The sealing part is a mold apparatus for reinforced plastic molding, characterized in that provided along the outer surface of the lower mold. The method of claim 2, The sealing member is formed of a material having an elastic force to form a band-like airtight member; A mounting bracket for pressing and fixing a side surface of the airtight member so that the airtight member is fixed to the lower mold outer surface; And Molding device for reinforced plastic molding, characterized in that it comprises a fastening screw for fixing the mounting bracket to the lower mold. The method of claim 3, wherein The hermetic member is a mold apparatus for reinforcing plastic molding, characterized in that formed of silicon material. The method of claim 3, wherein The airtight member protrudes outside the mounting bracket and is located between the upper mold and the lower mold; And Reinforced plastic molding mold apparatus characterized in that it comprises a body member connected to the head member and fixed between the mounting bracket and the lower mold. delete The method of claim 1, Molding device for reinforced plastic molding, characterized in that between the pipe member and the pump member is provided with a check valve to prevent the outside of the air flow back to the inner space. The method of claim 1, Molding device for reinforced plastic molding, characterized in that the pressure sensor is provided between the pipe member and the pump member. Mounting a reinforcing fiber on the lower mold to be joined with the upper mold; Forming an inner space by combining the upper mold and the lower mold; Exhausting the air in the inner space to the outside to form a vacuum state; Supplying a synthetic resin of a liquid phase to the inner space and molding the liquid; And After the synthetic resin is solidified, demolding, and taking out the product, In the step of supplying and molding the synthetic resin, the vacuum pressure of the inner space is measured to maintain the vacuum state set by further exhausting air. delete The method of claim 9, The vacuum pressure required for the inner space is a molding method of the reinforced plastics, characterized in that 0.6 to 0.8 bar.

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