KR102390559B1 - Forming method between SMC sheet and prepreg using reinforcing member - Google Patents

Abstract

An integrated forming method between a SMC sheet and a prepreg using a reinforcing member according to the inventive concept comprises the steps of: disposing a resin member made of the SMC sheet and the prepreg; arranging the reinforcing member integrally molded so as to an outer side of the resin member; and stacking and forming to wrap at least one surface of the SMC sheet and the prepreg through the reinforcing member having a protruding rib formed on an outside thereof, wherein the reinforcing member promotes binding in a state in which the reinforcing member is disposed on an end of the resin member, and the protruding rib is formed in a state in which the protruding rib is inserted into the SMC sheet and/or prepreg.

Description

A method of integrally forming between an SMC sheet and a prepreg using a reinforcing member

The present invention relates to a method for integrally forming between an SMC sheet and a prepreg using a reinforcing member.

Recently, as the weight reduction of body parts is accelerated due to the strengthening of regulations related to the automobile environment and fuel economy, the cases of manufacturing automobile parts using next-generation high-strength lightweight materials are increasing. In order to respond to policies to strengthen regulations on greenhouse gas emissions and achieve eco-friendly and high fuel efficiency, major automakers are continuously developing technologies for reducing vehicle weight using composite materials.

Various candidates such as electric vehicles, solar vehicles, hybrid vehicles, and fuel cell vehicles (hereinafter referred to as hydrogen electric vehicles) are being discussed as future eco-friendly vehicles, and the eco-friendly vehicle market is expected to gradually expand. It is necessary to reduce the weight of the hydrogen fuel cell powertrain system of the hydrogen electric vehicle, and it is necessary to secure the technology to reduce the weight and secure the productivity of the stack enclosure in which the existing metal parts are adopted.

As the eco-friendly vehicle market such as hydrogen electric vehicles matures, the heavy weight of eco-friendly car parts required for this purpose acts as a factor to increase the weight of the entire vehicle. desperate situation.

As the assembly process is simplified through process improvement to reduce the number of vehicle parts and the CO2 regulation is strengthened, there is a growing demand for weight reduction in automobiles to improve fuel efficiency.

Although the use of lightweight materials such as fiber-reinforced composite materials has a great weight saving effect, automakers are adopting a passive method of reducing weight through changes in structure and construction method while using existing materials in consideration of economic feasibility. Considering that the weight of a vehicle is rather increasing as consumer demand for it increases, it is expected that material changes will be inevitable in order to promote epoch-making weight reduction.

Fiber-reinforced composite material is the most effective material among vehicle lightweight materials, but it is not actively adopted by automakers due to lack of mass productivity and high price. It is developing materials, molding processes and equipment suitable for automobile parts, so it is expected to be applied in a short time. In particular, since the thermoplastic fiber-reinforced composite material does not require a chemical reaction in the molding process, the molding time is very short (less than 1 minute), so the manufacturing cost is low and it is easy to process.

On the other hand, in the case of SMC material, a composite material for compression molding, it has excellent surface quality and weather resistance and is widely applied in various high-strength and light-weight fields because it is excellent in mass production by using the press molding method, but short fibers are used as reinforcing fibers. There is a limit in the process of maximizing the high strength and light weight properties required for structural parts. The SMC process technology is used for automotive interior and exterior parts and construction materials, and is actively applied to the parts industry that requires high strength and durability.

Korean Patent Registration No. 10-2002137 proposes a method for manufacturing a flame retardant Korean paper fusion type SMC molded article with excellent flame retardant properties while maintaining the surface texture of Korean paper on the surface of the molded article by stacking flame retardant SMC sheets.

(Patent Document 1) KR 10-2002137 B

An object of the present invention is to provide a method for integrally forming an SMC sheet and a prepreg using a reinforcing member.

An integral molding method between an SMC sheet and a prepreg using a reinforcing member according to the present invention for achieving the above object comprises: disposing a resin member made of the SMC sheet and the prepreg; disposing a reinforcing member integrally molded to surround the outside of the resin member; and laminating and molding to surround at least one surface of the SMC sheet and the prepreg through a reinforcing member having protruding ribs formed on the outside, wherein the reinforcing member is disposed on the end of the resin member to promote bonding and the protruding ribs are molded while being inserted into the SMC sheet and/or prepreg.

The reinforcing member has a structure in which a first bracket disposed on an upper portion and a second bracket disposed on a lower portion are fitted, and the SMC sheet and/or prepreg is sandwiched between the first bracket and the second bracket. it becomes

The mold assembly for performing the integral molding method includes a lower mold and an upper mold that is installed on the upper part of the lower mold to raise and lower and press the prepreg and SMC sheet placed in the lower mold to integrally mold the lower mold, An SMC sheet is disposed on the upper side of the prepreg in a state in which the prepreg is fixed, and as the upper mold is lowered, the SMC sheet is pressed and flowed, so that the prepreg is inserted into the SMC sheet and integrally formed.

The method for integrally molding between the SMC sheet and the prepreg using the reinforcing member according to the present invention as described above uses a resin member made of the SMC sheet and the prepreg and a reinforcing insert member integrally molded to surround the outside of the resin member. It is characterized in that the MC sheet and the prepreg are integrally molded.

After disposing the SMC sheet on the prepreg in the above state, the SMC sheet and the prepreg are integrally molded by lowering and pressing the upper mold onto the lower mold.

The present invention proposes a method for solving the problem that the fiber arrangement of the prepreg flows due to the resin discharged from the SMC sheet during conventional compression molding.

1 is a block diagram showing a mold apparatus using integral molding of an SMC sheet and a prepreg according to an embodiment of the present invention;
FIG. 2 shows an operation concept of the mold apparatus of FIG. 1 .
3 shows an example in which the SMC sheet and the prepreg are integrally molded using a resin member laminated with the SMC sheet and the prepreg, and a reinforcing member integrally molded to surround the outside of the resin member.
4 shows another example of integrally molding the SMC sheet and the prepreg using a resin member laminated with the SMC sheet and the prepreg, and a reinforcing member integrally molded to surround the outside of the resin member.
5 is a configuration diagram showing a state in which SMC sheets are joined in a state in which a prepreg is fixed using a fixing pin formed in a lower mold on the mold apparatus of FIG. 1;
6 shows a forming process between the SMC sheet and the prepreg of FIG. 5 .
7 is a view for explaining the forming process between the SMC sheet and the prepreg through the rib groove formed on the lower mold.
8 shows an embodiment of the rib groove formed in the lower mold in FIG. 7 .
9 to 10 show the arrangement structure between the SMC sheet and the prepreg.
11 is a block diagram showing a molding apparatus for manufacturing an SMC sheet according to an embodiment of the present invention;
12 is an exemplary view showing schematic components of a forming apparatus for manufacturing an SMC sheet according to an embodiment of the present invention.

Hereinafter, embodiments of the present invention will be described in more detail with reference to the accompanying drawings. However, the present invention is not limited to the embodiments disclosed below, but will be implemented in various different forms, and only these embodiments allow the disclosure of the present invention to be complete, and the scope of the invention to those of ordinary skill in the art It is provided for complete information. In the drawings, like reference numerals refer to like elements.

In adding reference numerals to the components of each drawing, it should be noted that the same components are given the same reference numerals as much as possible even though they are indicated on different drawings. In addition, in describing the present invention, if it is determined that a detailed description of a related known configuration or function may obscure the gist of the present invention, the detailed description thereof will be omitted.

According to the present invention, SMC used in the method for manufacturing vehicle parts using integral molding of SMC sheet and prepreg is a composite material on a sheet consisting of resin, fiber reinforcement, filler and various additives, and is basically a high corrosion resistance, strength, rigidity, It has excellent mechanical properties such as impact resistance, and even parts with very complex shapes can be produced in a single process to match the final required shape. do.

SMC has advantages such as light weight of parts, very high dimensional stability, very efficient thermal expansion properties comparable to that of metal materials, excellent heat resistance, excellent design, freedom of shape, high productivity, and excellent productivity in low molding pressure. Its use is gradually expanding to products, construction materials, and interior and exterior materials for automobiles. SMC is a thermosetting composite molding material made into a sheet with a thickness of 1 to 3 mm by impregnating a reinforcing material (carbon fiber) cut to about 1 inch in a compound mixed with fillers and additives in an unsaturated polyester resin. It improves surface smoothness, coating performance, shrinkage rate, dimensional stability, impact strength, adhesive performance, and processing performance, which are disadvantages.

1 and 2, the mold assembly protrudes from the side of the main mold 110 and the main mold 110 to form a fixing part 122 into which the prepreg is inserted and fixed, and an elastic body disposed on the lower side. A lower mold 100 made of a lifting mold 120 driven so as to be lifted by 130 and a prepreg 150 installed in the upper part of the lower mold 100 and raised and placed in the lower mold 100 and It is configured to include an upper mold 200 integrally molded by pressing the SMC sheet 160 .

The SMC sheet 160 is disposed on the upper side of the prepreg 150 in a state in which the prepreg 150 is fixedly disposed on the fixing part 122 of the lower mold 100, and as the upper mold 200 descends The SMC sheet 160 is pressed and flowed and at the same time the elevating mold 120 is lowered in a state supported by the elastic body 130, the prepreg 160 is integrally formed to be inserted into the SMC sheet 160. . In order to prevent the lower mold from descending from the beginning of the upper mold in the mold assembly, the elastic body 103 is operated when the upper mold and the lower mold are within a certain range. That is, the initial sudden drop of the upper mold is prevented by the strength of the elastic body.

The elevating mold 120 is provided with a fixing module 140 for fixing the elevating mold 120 so that elevating and lowering of the elevating mold 120 is not made until the upper mold 200 descends to a predetermined distance from the lower mold 100 . .

Referring to FIG. 3 , in the bonding structure of the resin member 170 made of the SMC sheet 160 and the prepreg 150 and the reinforcing member 180 integrally molded so that the outside is wrapped around the resin member, the reinforcing member 180 ) is formed on the outside of the protruding ribs 182, and the SMC sheet and the prepreg are laminated to surround at least one surface of the protruding ribs. The reinforcing member 180 is disposed on the end of the resin member 170 for the purpose of promoting cohesion.

The protruding ribs 182 are formed while being inserted into the SMC sheet and/or the prepreg.

It is molded in a state in which the SMC sheet and/or the prepreg is sandwiched between the protruding ribs 182 .

Referring to FIG. 4 , in the bonding structure of a resin member made of an SMC sheet and a prepreg and an insert member integrally molded to be wrapped around the outside of the resin member, the reinforcing member 180 includes a first bracket disposed on the upper portion and a lower portion of the resin member. It consists of a structure in which the second bracket disposed on the That is, the SMC sheet and/or the prepreg is formed between the first and second brackets.

A fitting portion 184 protruding outwardly is disposed on one side of the upper and lower ends of the first and second brackets. In a state in which the first and second brackets are disposed between a resin member made of an SMC sheet and a prepreg, the first Proceed with fitting between the bracket and the second bracket. In the above process, the fitting portions constituting the first and second brackets are stably coupled through fitting structures disposed on the inner and outer sides, respectively.

An example for coupling between the prepreg 150 and the SMC sheet 160 will be described with reference to FIGS. 5 to 6 .

On the upper mold 200 and the lower mold 100 constituting the mold assembly, the SMC sheet 160 is bonded in a state in which the prepreg 150 is fixed using the fixing pins 112 formed to be movable up and down in the lower mold. .

First, the prepreg 150 is protruded on the upper surface of the main mold 110 constituting the lower mold and is placed on the fixing pin 112 so as to be able to enter into the fixing pin insertion groove 111 formed in the main mold 110 . A prepreg is placed on the lower mold in a state in which the fixing hole 152 formed through the upper and lower parts of the dies is inserted.

Next, an SMC sheet is placed on the prepreg.

Next, the SMC sheet and the prepreg are integrally molded by lowering the upper mold onto the lower mold.

In this step, when the upper mold is lowered, the fixing pin 112 is inserted into the fixing pin insertion groove 111 formed in the main mold 110, and the SMC sheet penetrates into the fixing hole 152 of the prepreg. By curing, it is possible to integrally form the SMC sheet and the prepreg with improved bonding strength between the SMC sheet and the prepreg.

Meanwhile, the fixing hole 152 of the prepreg is characterized in that it has a circular or polygonal shape, and the fixing hole 152 of the prepreg is provided in the form of a slit.

7 to 8 , the molding process between the SMC sheet and the prepreg through the rib groove 114 formed on the main mold 110 constituting the lower mold and the embodiment of the rib groove formed in the lower mold are shown.

First, the main mold 110 in which the rib groove 114 for rib molding is formed is prepared. The prepreg 150 in which the fixing hole 152 is formed is disposed on the plurality of rib grooves 114 formed in the main mold 110 . Next, the SMC sheet 160 is positioned above the prepreg 150 .

Next, the SMC sheet and the prepreg are integrally molded by pressing the upper mold in the direction of the lower mold, and at the same time, the SMC sheet passes through the prepreg and hardens in the rib groove, thereby forming ribs.

In the above process, a fixing hole 152 that is an outlet space through which the SMC sheet can pass is formed in the prepreg 150 corresponding to the rib groove 114 .

Thereafter, the prepreg may be placed in a cured state, and an adhesive film may be disposed on the upper side of the prepreg.

9 to 10 show the arrangement structure of the SMC sheet and the prepreg for improving the formability.

In the step of placing the prepreg 150 on the lower mold 100 and placing the SMC sheet 160 on the prepreg upper part, the prepreg is easily inserted into one side of the SMC sheet to improve the moldability. As a method, a plurality of SMC sheets are arranged along the edge of the prepreg.

Specifically, the plurality of SMC sheets 160 are arranged so that the edge of the prepreg 150 and a part overlap.

On the other hand, the SMC sheet is arranged so as to be vertically symmetrical with respect to the prepreg.

As described above, an SMC-prepreg composite is formed by pressing while placing an SMC plate on the molded prepreg.

Pressing is performed by first inserting a prepreg in the shape of a thin long plate between the upper and lower molds. Place the SMC plate in the shape of a wide plate on the mold on which the pressed prepreg is placed. Secondary pressing is performed in the above state.

The SMC plates separated in the secondary pressing process are connected while being spread widely.

As a result, it has a shape in which the prepreg is reinforced on the SMC plate.

11 to 12, a carbon fiber-based SMC sheet manufacturing method will be described.

According to an embodiment of the present invention, a molding apparatus for manufacturing an SMC sheet includes a transfer unit 20 , a conveyor unit 30 , a coated fiber supply unit 40 , and a pressing roller unit 60 and a fiber dispersion supply unit 200 . is composed

The transfer unit 20 may include one or more transfer rollers, and serves to transfer the original film 10 in a wound state to the inside of the facility. At this time, as the original film 10, a resin film or a decorative film may be selectively adopted.

The conveyor unit 30 is provided with an application box 32 so as to apply a liquid unsaturated polyester resin to the original film 10 transferred along the conveying unit 20 . In addition, a conveyor belt 33 and an operating roller 31 are installed on the conveyor unit 30 to transport the original film 10 , and the application box 32 is installed to be located on the conveyor belt 33 . .

The coated fiber supply unit 40 serves to form the processed film 100 by coating carbon fibers 41 or glass fibers on the original film 10 transferred along the conveyor belt 33 .

As a configuration for this, the coated fiber supply unit 40 is provided with a plurality of conveying rollers 42 and 43 so that carbon fibers or glass fibers are embedded in the original film 10 to be moved. At this time, of course, the carbon fiber or glass fiber may be supplied in a state cut to 1 to 70 mm by a separately installed cutting facility.

The compression roll 60 is configured to compress and impregnate the processed film 100 drawn out from the coated fiber supply unit 40 . That is, a plurality of films, such as carbon fiber 41 or glass fiber, are introduced in a laminated state in the processed film 100 introduced into the pressing roll 60 , and while passing through the pressing roll 60 , these films are subjected to high pressure It is pressed and adhered to each other.

Meanwhile, a film supply unit 50 may be installed between the coated fiber supply unit 40 and the compression roller unit 60 . The film supply unit 50 serves to provide an APP film 51 or a decorative film to the processed film 100 to be transferred.

As a configuration for this, the film supply unit 50 includes a supply roll 52 on which the supply film is wound, and a plurality of transfer rolls 55 for transferring the supplied film. Here, the above-described application box 53 is installed between the transfer rolls 55 , and a thermosetting resin may be applied to the original film 10 transferred through the application box 53 .

The thermosetting resin (unsaturated polyester resin) as described above acts as an adhesive medium between the film and the film.

The forming roller unit 70 is installed on the horizontal line of the pressing roller 60 and serves to heat and compress the processed film 100 drawn out from the pressing roller 60 into a predetermined shape. Specifically, a plurality of pressure rollers are installed to have a pair of upper and lower pressure rollers, respectively. In the heat compression process, the processing film introduced through a plurality of heating elements disposed on the forming roller unit 70 is heated. The forming roller 70 may be removed during the SMC composite manufacturing process if necessary.

A plurality of pressure rollers are arranged in the advancing direction of the incoming film, and each of the press rollers has a deeper curve formed on the outer peripheral surface of the upper and lower pressure rolls as the film moves in the advancing direction. In order to prevent the formation of wrinkles on the flat plate of the processed film, the pattern shape is sequentially formed.

First, a thickener is administered after the paste is prepared.

After supplying the compound to the duct box, the compound is first put on the film.

After supplying carbon fiber (C/F) primarily, carbon fiber is supplied secondary. This controls the amount of cut fibers, and since it is impossible to supply a large amount of fibers at one time, carbon fibers are supplied in 1st and 2nd divisions.

Next, the compound is added to the film secondarily. The primary compound input is to supply the cut carbon fibers to the lower part before supplying them, and the secondary compound input is a process for supplying the cut carbon fibers to the bottom to become a Compound-Carbon Fiber-Compound.

Next, the sheet is first impregnated, and the sheet is impregnated secondarily.

Finally, after sheet packaging, aging and shipping are performed.

The type of SMC material uses resin (UP), low shrinkage agent and additives.

As additives, dispersants, inhibitors, initiators (curing agents), retarders (initiation retarders), improvers, fillers, internal release agents, and the like are used.

SMC input weight uses the formula of width X length X height X specific gravity.

SMC molding pressure uses the formula of width X length X pressure.

The above description is merely illustrative of the technical spirit of the present invention, and various modifications and variations will be possible without departing from the essential characteristics of the present invention by those skilled in the art to which the present invention pertains. Accordingly, the embodiments disclosed in the present invention are not intended to limit the technical spirit of the present invention, but to explain, and the scope of the technical spirit of the present invention is not limited by these embodiments. The protection scope of the present invention should be construed by the following claims, and all technical ideas within the scope equivalent thereto should be construed as being included in the scope of the present invention.

Claims (2)

In the integral molding method between an SMC sheet and a prepreg using a reinforcing member,
disposing a resin member made of an SMC sheet and a prepreg;
disposing a reinforcing member integrally molded to surround the outside of the resin member; and
Including; lamination molding to surround at least one surface of the SMC sheet and the prepreg through a reinforcing member having protruding ribs formed on the outside;
The reinforcing member promotes bonding while being disposed on the end of the resin member, and the protruding rib is molded while being inserted into the SMC sheet and/or prepreg,
The reinforcing member has a structure in which a first bracket disposed on an upper portion and a second bracket disposed on a lower portion are fitted, and the SMC sheet and/or prepreg are sandwiched between the first bracket and the second bracket. An integral molding method between the SMC sheet and the prepreg using a reinforcing member, characterized in that
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