KR102277959B1 - Apparatus for preparing long fiber reinforced sheet using prepreg - Google Patents

Abstract

The present invention relates to an apparatus for manufacturing a long fiber reinforced sheet using a prepreg, and more particularly, to an apparatus for manufacturing a long fiber reinforced sheet in which formability and productivity are improved by using a prepreg to which reinforcing fibers are applied. Insertion guide portion 10 for supplying the one-way prepreg (2) in the longitudinal direction; a slitting unit 20 for cutting the prepreg supplied from the insertion guide unit 10 in the longitudinal direction to form a plurality of prepreg tapes 4 extending in the longitudinal direction; a cutting portion (50) for cutting the prepreg tape (4) extending in the longitudinal direction in a vertical direction in the longitudinal direction to form a plurality of prepreg chips (6); a collecting plate 66 from which the prepreg chips 6 formed in the cutting part 50 fall and are collected in the form of a sheet; and a long fiber reinforced sheet manufacturing apparatus including a pressing unit 70 for melt-compressing the prepreg chips 6 collected in the sheet form from the collection plate 66 .

Description

Long fiber reinforced sheet manufacturing apparatus using a prepreg {Apparatus for preparing long fiber reinforced sheet using prepreg}

The present invention relates to an apparatus for manufacturing a long fiber reinforced sheet using a prepreg, and more particularly, to an apparatus for manufacturing a long fiber reinforced sheet having improved formability and productivity by using a prepreg to which reinforcing fibers are applied.

Prepreg is an abbreviation of “Preimpregnated Material” and refers to a sheet-type product in which a matrix is pre-impregnated with reinforcing fibers, and is used as an intermediate material for molding composite materials. In general, prepregs are divided into unidirectional prepregs in which reinforcing fibers are aligned in one direction and woven prepregs in which reinforcing fibers are formed in a woven fabric. In a typical prepreg, carbon fibers having high strength and elasticity are used as reinforcing fibers, and polymer resins such as epoxy resins are mainly used as a base material.

Looking at the reason why prepreg is applied to composite material molding, it has an excellent advantage in that the ratio of the base material (resin) and the reinforcing material (reinforcing fiber) can be precisely controlled, so that the physical properties of the designed material can be maximized. In addition, since the composite material molding process using the prepreg uses an intermediate material, the cost of the raw material is high, but since the molding process is clean and simple, the operation cost can be reduced. Prepreg mainly has a sheet shape, so it is easy to handle and energy cost is reduced during molding, and the number of parts required for processing can be reduced due to the nature of cutting and molding, and prepreg can be applied not only in sheet shape but also in tape shape and chip shape. It is widely used as an intermediate material for molding composite materials in various industrial fields such as aviation, space, automobile, sports, leisure, civil engineering, and construction due to the advantage that it can be easily processed into various shapes. However, conventional unidirectional or woven prepregs have excellent rigidity, but have a high density and are heavy, and in order to obtain desired rigidity, several layers of prepregs must be laminated, thereby increasing the thickness of the molded article. In addition, in the case of a unidirectional prepreg, since the lamination direction must be considered in order to impart isotropy to the molding, there is a limit to molding a complex structure.

Accordingly, an object of the present invention is to provide an apparatus for manufacturing a long fiber reinforced sheet using a prepreg.

Another object of the present invention is to provide an apparatus for manufacturing a long fiber reinforced sheet that uses a prepreg to which a reinforcing fiber is applied, and has improved formability and productivity.

In order to achieve the above object, the present invention is an insertion guide portion 10 for supplying the one-way prepreg (2) in the longitudinal direction; a slitting unit 20 for cutting the prepreg supplied from the insertion guide unit 10 in the longitudinal direction to form a plurality of prepreg tapes 4 extending in the longitudinal direction; a cutting portion (50) for cutting the prepreg tape (4) extending in the longitudinal direction in a vertical direction in the longitudinal direction to form a plurality of prepreg chips (6); a collecting plate 66 from which the prepreg chips 6 formed in the cutting part 50 fall and are collected in the form of a sheet; and a pressing unit 70 for melt-compressing the prepreg chips 6 collected in the sheet form from the collection plate 66 .

As described above, the apparatus for manufacturing a long fiber reinforced sheet using a prepreg according to the present invention can manufacture a long fiber reinforced sheet with improved physical properties, formability, and productivity above the metal level.

1 is a schematic view of the overall long fiber reinforced sheet manufacturing apparatus according to the present invention.
2 is a view showing an insertion guide unit 10 device according to the present invention.
3 is a view showing the operating principle of the slitting unit 20 according to the present invention.
4 is a view showing a cutting method of the slitting unit 20 according to the present invention.
5 is a view showing a cutter type of the cutter unit 50 according to the present invention.
6 is a view showing a separation means of the cutter unit 50 according to the present invention.
7 is a view showing a process in which the prepreg chips 6 formed in the cutter unit 50 according to the present invention are collected in a sheet form.
8 is a schematic view of the overall long fiber reinforced sheet manufacturing apparatus according to another embodiment of the present invention.
9 is a view showing the pressing roller 74 of the pressing unit 70 according to the present invention.

Hereinafter, the present invention will be described in more detail with reference to the accompanying drawings.

1 is a schematic diagram showing the overall configuration of a long fiber reinforced sheet manufacturing apparatus according to the present invention. 1, the apparatus for manufacturing a long fiber reinforced sheet of the present invention (hereinafter, LFPS [Long Fiber Prepreg Sheet]) includes an insertion guide unit 10, a slitting unit 20, a cutting unit 50 and a pressing unit ( 70), and, if necessary, may further include a separation guide unit 40 and the like.

The insertion guide part 10 serves to supply the one-way prepreg 2 in the longitudinal direction. Here, the longitudinal direction means the longitudinal direction of the fibers included in the unidirectional prepreg (2). As described above, the unidirectional prepreg 2 is a prepreg in which fibers are arranged in one direction in a resin, and the reinforcing fibers are carbon fiber, glass fiber, basalt fiber, amamid, polypropylene, polyphenylene sulfide (PPS) Both organic/inorganic fibers such as polymer-based fibers can be used, and as the base material, thermosetting resins such as epoxy, unsaturated polyester, and phenol, polyethylene, polypropylene, urethane, polyphenylene sulfide, polyether ether ketone, etc. A thermoplastic resin comprising a may be used. The width (vertical direction of the unidirectional fiber) of the prepreg is 300 to 1500 mm, preferably 500 to 1000 mm, and can be freely manufactured and used to a required length.

As shown in FIG. 1 , the insertion guide part 10 includes a feed roller 12 on which a one-way prepreg 2 is wound and a one-way prepreg 2 wound on the feed roller 12 . Includes a guide roller (14, Guide roller) for guiding the slitting (20). 2 is a view showing a specific example of the insertion guide unit 10 . In the example shown in FIG. 2 , the insertion guide part 10 is a slitting unit for the supply roller 12 on which the unidirectional prepreg 2 is wound, and the unidirectional prepreg 2 wound on the supply roller 12 . Guide roller 14 leading to (20), a puller (16, Puller) that pulls the unwound one-way prepreg (2) and moves it to the slitter part (20), and the puller (16) from the puller (16) to the slitter part (20) It includes a guide plate (18, Guide plate) for moving.

The supply roller 12 adjusts the tension, and unwinds the one-way prepreg 2 in a roll state. The supply roller 12 may include a brake to adjust the tension. The unwound one-way prepreg 2 is moved to the puller 16 by the guide roller 14 that moves while adjusting the left and right tension. The guide roller 14 comprises 1 to 6, preferably 2 to 4 rollers 14 . If the length to the puller 16 is long, it may be additionally installed, but it is not necessary to install a large amount. The puller 16 is a roller that pulls the unwound one-way prepreg 2 so that it can be inserted into the slitter part 20 . The surface of the roller of the puller 16 may be made of a SUS material, but may include rubber-coated rubber to uniformly apply tension. The puller 16 may include at least one roller. The one-way prepreg 2 passing through the puller 16 moves to the slitter part 20 past the guide plate 18 . If the tackiness (Tacky) of the unidirectional prepreg 2 is high, the resin may adhere to the slitter blade of the slitting unit 20, thereby causing blade wear. Therefore, it is possible to prevent this by including a chiller in the guide plate 18 .

The slitting unit 20 is a device for forming a plurality of prepreg tapes 4 extending in the longitudinal direction by cutting the one-way prepreg 2 supplied from the insertion guide unit 10 in the longitudinal direction. The width of the prepreg tape 4 is 5 to 25 mm, preferably 6 to 25 mm, more preferably 8 to 10 mm, for example 8 mm, and the thickness is the same as the thickness of the prepreg. . Here, when the width of the prepreg tape 4 is too wide, there is a problem that molding processability is lowered, and when it is too narrow, there is a problem that the reinforcing material is cut and causes defects.

3 is a view for explaining the operating principle of the slitting unit 20 used in the long fiber reinforced sheet manufacturing apparatus of the present invention. As shown in FIG. 3 a, using the top view 21, the unidirectional prepreg 2 is cut to a constant width in the fiber 0° direction (length direction), or as shown in FIG. 3 b, While the multiple blades composed of the upper blade 22 and the lower blade 23 are engaged with each other, the unidirectional prepreg 2 is cut to a constant width in the longitudinal direction by the interval of the multiple blades composed of the upper blade 22 and the lower blade 23. A leg tape 4 is formed.

4 is a view showing a cutting method of the slitting unit 20 used in the long fiber reinforced sheet manufacturing apparatus of the present invention. The slitter unit 20 may select a slitting method in consideration of the adhesiveness of the resin and the width of the long fiber reinforced sheet (8, LFPS) chip. The slitting method includes laser cutting (Razor cutting. [Fig. 4 a]), shear cutting (Fig. 4 b), Score cutting, [Fig. 4 c]), special gang cutting (Special Gang cutting, [Fig. 4 d]) and the like. The laser cutting [Fig. 4a] is a slitting method using a commercially available razor blade 24. Even in laser cutting, aerial cutting laser cutting is easy to use because of its simple mechanism and operation, and it is easy to adjust the spacing of the desired slit width and to change the blade. In general, various film materials and pharmaceuticals, except for hard and thick materials. It can be used for a laminate film for food, etc. The shear cutting [Fig. 4b] is a pair of upper and lower blades (25, 26) set on the outside of a rotating circular knife, such as scissors, and the upper and lower blades (25, 26) are engaged and slit. In general, shear cutting is used for products or materials that require precision, and is used to slit hard or thick materials and films that are impossible with laser cutting. The score cutting [FIG. 4 c] is a method of cutting the material by pushing the round blade 27 to the hard lower roll 28 and inserting a cut into the material. It is mainly used for slitting various adhesive tapes or for trimming both ends in the lamination process. The special gang cutting (Fig. 4d) is slit while the upper coat 29 and the lower coat 30 are engaged.

The cutting unit 50 is a device for forming prepreg chips by cutting a plurality of prepreg tapes 4 extending in the longitudinal direction in a vertical direction in the longitudinal direction. The length of the prepreg chip 6 is determined according to the insertion speed of the prepreg tape 4 and the speed of the cutter unit 50 . The vertical cut length of the prepreg tape 4 is 10 to 100 mm, preferably 15 to 80 mm, more preferably 25 to 50 mm. Here, when the cut length is too long, there is a problem in that moldability and dispersion degree are lowered, and when it is too short, there is a problem in that physical properties are lowered. In this way, the unidirectional prepreg 2 is cut in the longitudinal and vertical directions to obtain a prepreg chip having a width of 8 to 10 mm and a length of 25 to 50 mm.

As the cutting unit 50 , a conventional cutting device capable of forming the prepreg chips 6 by cutting the prepreg tape 4 in the vertical direction in the longitudinal direction may be used. 5 is a view showing the type of the cutting unit 50 that can be used in the long fiber reinforced sheet manufacturing apparatus of the present invention. As shown in FIG. 5 , as the cutting unit 50 , a guillotine cutter 51 ( FIG. 5 a ) and a rotary cutter 56 , a rotary cutter ( FIG. 5 b ) may be used. The guillotine cutter 51 has the shape of a cut head, and cuts the prepreg tape 4 horizontally by using the upper cut 53 and the lower cut 55 . The number of cuts per minute of the guillotine cutter 51 may be calculated by the following equation.

For example, when the cutting speed of the guillotine cutter 51 is 1 m/min of the insertion speed of the prepreg tape 4 and the maximum length of the prepreg chip 6 is 0.08 m, the minimum cutting speed is 12.5 times per minute. can have speed. The maximum cutting speed of the guillotine cutter 51 is an insertion speed of 10 m/min, and when the prepreg chip 6 is manufactured with a minimum length of 0.015 m, a guillotine cutter in a range that can have a cutting speed of 666.67 per minute is required In reality, there are difficulties in building facilities. Therefore, it is preferable to have a cutting speed of 200 times per minute by making the insertion speed 3 m/min and the minimum length of the prepreg chip 6 0.015 m.

The rotary cutter 56 cuts the prepreg tape 4 by the interval of the blade 57 while rotating. The number of blades 57 of the rotary cutter may be determined in consideration of the diameter and strength of the rotary cutter 56 . The blade 57 of the rotary cutter is usually made of 2 to 6, for example, includes four blades (57). The length of the prepreg chip 6 may be adjusted in consideration of the rotation speed of the rotary cutter 56 and the interval between the blades 57 .

The rotation speed of the rotary cutter 56 can be calculated by the following equation.

For example, when manufactured at an insertion speed of 1 m/min based on the quadruple blade of the rotary cutter 56 and a maximum length of 0.08 m of the prepreg chip 6, the rotary cutter 56 may have a rotation speed of at least 3.125 rpm. When the insertion speed is 10 m/min and the minimum length of the prepreg chip 6 is 0.015 m, it can have a maximum cutting speed of 166.67 rpm per minute, and the rotary cutter 56 in the above range is preferable.

In the case of the guillotine cutter 51, the product productivity may be lower than that of the rotary cutter 56 because there is a limit value of the cutting speed, so it is preferable to use the rotary cutter 56 in the present invention.

A prepreg chip separating means for separating the cut prepreg chip 6 from the cutting part 50 may be further provided at the rear end of the cutting part 50 . There is a phenomenon in which the prepreg chip 6 becomes sticky and cannot be separated from the rotary blade 57 . To solve this, prepreg chip separation means are used. 6 is a view showing the prepreg chip separating means. As shown in FIG. 6 , the prepreg chip separation means may be an air knife 58 (a in FIG. 6), a brush roller 59 (b in FIG. 6), or the like. The air knife separates the prepreg chip 6 from the rotary blade 57 by injecting condensed air. The brush roller 59 may be installed at the rear end of the rotary cutter 56 to physically separate the prepreg chips 6 .

The prepreg chips 6 formed in the cutting portion 50 are collected in a sheet form at the collecting plate 66 . 7 is a view showing a process in which the prepreg chips 6 are collected in a sheet form. As shown in FIG. 6 , the prepreg chips 6 formed in the cutting portion 50 are randomly dispersed and fall onto the collecting plate 66 . At this time, a discharge port 64 for collecting and discharging the prepreg chips 6 is included so that the prepreg chips 6 can be collected on the plate 66 . As the collection plate 66 is a heated plate, the viscosity of the resin may increase, and adhesion may occur between the prepregs to be in close contact with each other.

The reason why the prepreg chips 6 are randomly dispersed is that, in the case of a unidirectional prepreg, the stacking direction must be considered in order to impart isotropy to the molding, and there is a limit when forming a complex structure. This is because, if the leg chips 6 are randomly distributed, this limitation can be overcome and moldability and productivity can be improved. An air blower may be used to improve the dispersion.

The distance between the cutting part 50 and the collecting plate 66 may be appropriately set according to the degree of dispersion of the prepreg chips 6 , the size and density of the prepreg chip sheet, and the like. The distance between the cutting part 50 and the collecting plate 66 is 400 to 800 mm, preferably 500 to 700 mm. If it is too high, the fiber arrangement and dispersion are good, but there is a problem in that the prepreg chips 6 falling out of the sheet width of the set product increase, and if it is too low, the fibers fall in an arrangement close to 0° (lengthwise). , there is a problem of poor dispersion.

8 is a schematic diagram showing the overall configuration of an apparatus for manufacturing a long fiber reinforced sheet according to another embodiment of the present invention. In the embodiment shown in FIG. 8 , as the cutting unit 50 , two or more cutting devices 52 , 54 having different falling distances of the prepreg chips 6 are used. As shown in FIG. 8 , the distance between the first cutting device 52 and the collecting plate 66 is set to be greater than the distance between the second cutting device 54 and the collecting plate 66 . The distance between the first cutting device 52 and the collecting plate 66 is generally 700 to 800 mm, and the distance between the second cutting device 54 and the collecting plate 66 is generally 400 to 500 mm.

As such, when the installation heights of the cutting devices 52 and 54 are different, the prepreg chip sheets having different degrees of dispersion, size, density, etc. have a superimposed structure, so that the formability and physical properties of the long fiber reinforced sheet are diversified. desirable.

As shown in FIG. 8, when two or more cutting devices 52 and 54 are used, the plurality of prepreg tapes 4 formed in the slitting unit 20 are separated into two or more cutting devices 52 and 54. A separation guide part 40 for supplying is installed between the slitting part 20 and the cutting part 50 .

The separation guide part 40 includes a take-out roller 42 for drawing out the prepreg tape formed in the slitting part 20 and two or more cutting devices 52 and 54 for the prepreg tape drawn out from the take-out roller 42. and guide rollers 44 and 46 for separating and moving.

The pull-out roller 42 is a device for drawing out the prepreg tape 4 supplied from the slitting part 20 to the cutting part 50 . An additional component may be included to adjust the tension of the take-out roller 42 .

The guide rollers 44 and 46 are devices for moving the prepreg tape emitted from the take-out roller 42 to two or more cutting devices 52 and 54 . Based on the position of the prepreg tape 4 supplied from the take-out roller 42, the odd-numbered prepreg tape 4 is applied to the first guide roller 44, and the even-numbered prepreg tape 4 is applied to the first guide roller 44. 2 guide rollers 46 are drawn out, respectively. For example, based on the position of the prepreg tape 4, the 1st, 3rd, and 5th prepreg tapes are drawn out on the first guide roller 44, and the 2nd, 4th, and 6th tapes are drawn on the second guide roller ( 46). The first guide roller 44 and the second guide roller 46 adjust the tension and move the prepreg tape 4 to two or more cutting devices 52 and 54 having different falling distances.

As shown in FIG. 1 , the pressing unit 70 is a device for melt pressing the prepreg chips 6 collected in the form of a sheet from the collecting plate 66 . When the collected prepreg chips 6 are compressed using a pressing roller 74, residual pores in the sheet can be minimized by heat and pressure. At the time of compression, the thickness of the long fiber reinforced sheet 8 may be adjusted according to the number and temperature of compression or the number of chips to be compressed. The number of times of compression is passed through the compression roller 74 at least once or more, and preferably 2-3 times are suitable, and compression of 3 times or more is unnecessary. The compression unit 70 may include a supply roller 72 for supplying a cover film to prevent the prepreg chip 6 from sticking and to serve as packaging.

9 is a view showing the pressing roller 74 of the pressing unit 70 . The compression unit 70 can set the number of compressions in order to obtain the long fiber reinforced sheet 8 with good productivity. When the compression is performed once, the density between the prepreg chips 6 is low, so that the Since it is thick and contains voids such as air or gas inside, problems in the molding process or physical properties after molding may be deteriorated. If the compression is performed three or more times, the thickness of the sheet 8 is reduced, but there is a possibility that the prepreg chips 6 may come off outside the set sheet 8 width due to heat and pressure, and the curing degree of the thermosetting resin may increase. can Therefore, pressing twice is suitable for removing the thickness and internal voids of the long fiber reinforced sheet 8, and thus the physical properties after molding are also excellent. With reference to this, the compression unit 70 uses two sets of rollers of the heating/pressurizing device, and since there are various resins applied to the prepreg, it is necessary to determine the characteristics of the resin to adjust the process temperature. The thermosetting resin should set the roller temperature above the temperature at which flowability occurs, but below the temperature at which the curing reaction occurs. The thermoplastic resin should be set at a temperature above the melting point, but below the boiling point. The pressure of the roller is applied to a pressure capable of minimizing the pores by compression, but it is necessary to apply a pressure sufficient to prevent the chip 6 from coming off.

The compression unit 70 further includes a winding roller 80 for winding the long fiber reinforced sheet 8 in a roll shape. The winding roller 80 is a device for winding the long fiber reinforced sheet 8 formed from the pressing unit 70 in the form of a roll. The long fiber reinforced sheet 8 is obtained in the form of a roll by the winding roller 80 . As described above, the long fiber reinforced sheet 8 obtained by the manufacturing apparatus of the present invention is used in various industries because it has improved physical properties, formability, and productivity above the metal level.

Claims (7)

Insertion guide portion 10 for supplying the one-way prepreg (2) in the longitudinal direction;
a slitting unit 20 cutting the prepreg supplied from the insertion guide unit 10 in the longitudinal direction to form a plurality of prepreg tapes 4 extending in the longitudinal direction;
a cutting portion (50) for cutting the prepreg tape (4) extending in the longitudinal direction in a vertical direction in the longitudinal direction to form a plurality of prepreg chips (6);
a collecting plate 66 from which the prepreg chips 6 formed in the cutting part 50 fall and are collected in the form of a sheet; and
and a pressing unit (70) for melt-compressing the prepreg chips (6) collected in the sheet form from the collection plate (66),
The slitting unit 20 forms a prepreg tape 4 by cutting the multiple blades composed of the upper blade 22 and the lower blade 23 to a uniform width in the longitudinal direction by the interval of the multiple blades while being engaged with each other,
It further comprises a separation guide part 40 for supplying the plurality of prepreg tapes 4 formed in the slitting part 20 separately to two or more cutting devices 52 and 54 having different falling distances,
The separation guide part 40 draws out the first guide roller 44 for taking out the odd-numbered prepreg tape 4 and the even-numbered prepreg tape 4 on the basis of the position of the prepreg tape 4 . Which will include a second guide roller (46), long fiber reinforced sheet manufacturing apparatus. The apparatus for manufacturing a long fiber reinforced sheet according to claim 1, wherein the prepreg chip (6) has a width of 8 to 10 mm and a length of 25 to 50 mm. The apparatus for manufacturing a long fiber reinforced sheet according to claim 1, wherein the cutting unit (50) includes two or more cutting devices (52, 54) having different falling distances of the prepreg chips (6). delete delete According to claim 1, wherein the distance between the cutting portion (50) and the collecting plate (66) will be 500 to 700 mm, long fiber reinforced sheet manufacturing apparatus. According to claim 1, wherein the unidirectional prepreg (2) is selected from the group consisting of a reinforcing fiber selected from the group consisting of carbon fibers, glass fibers, basalt fibers and polymer fibers, and epoxy resins, unsaturated polyesters, and phenolic resins. A long fiber reinforced sheet manufacturing apparatus comprising a stretching selected from the group consisting of a thermosetting resin or a thermoplastic resin selected from the group consisting of polyethylene, polypropylene, urethane-based resin, polyphenylene sulfide, and polyether ether ketone.

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