JP2014037101A - Production method of fiber-reinforced plastic made honeycomb core - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a production method of a corrugate method fiber-reinforced plastic made honeycomb core in which first, cost is excellent, second, an irregular shape honeycomb core can be produced also, third, thermal strain is not generated, and fourth, weight is reduced.SOLUTION: A production method uses a lot of piece member subjects 17 that meet a cell shape of a honeycomb core. In addition, a piece member subject group 18 is invaginated while interposing a prepreg 19, then each interposed prepreg 19 is perfectly hardened by heat and compression and mutual places are jointed, then the piece member subjects 17 of each piece member subject group 18 are removed. Therefore, a fiber-reinforced plastic made honeycomb core that comprises a flat surface aggregate of a lot of hollow columnar cells performed by block forming by a cell wall is produced. The production method includes a preparation process; an invagination setting process; a corrugate process; a heating and compression process; and a final process of the like.

Description

  The present invention relates to a method for manufacturing a honeycomb core made of fiber reinforced plastic. That is, the present invention relates to a method of manufacturing a honeycomb core made of fiber reinforced plastic (FRP) in which a resin is adhered and impregnated on a fiber base material.

《Technical background》
A honeycomb core consists of a flat aggregate of many hollow columnar cells partitioned by cell walls, and is superior in weight specific strength, planar accuracy (especially when used as a honeycomb sandwich panel), and others. It has.
The honeycomb core made of fiber reinforced plastic is further superior in light weight and corrosion resistance, and its cell wall is typically a fiber base material adhered and impregnated with a thermosetting resin. A typical one having a regular hexagonal cross-sectional shape.
Further, such a honeycomb core made of fiber reinforced plastic is manufactured by a so-called corrugated system or a stretch system, like other honeycomb cores. The present invention relates to a corrugated manufacturing method.

<Conventional technology>
In the corrugated method, a honeycomb core is manufactured by stacking and bonding corrugated sheets made of fiber reinforced plastic. Such a conventional corrugated manufacturing method will be described with reference to FIGS.
First, as shown in FIG. 5 (1), the sheet-like prepreg 1 is supplied to the corrugating apparatus 2 to be corrugated.
That is, the prepreg 1 in a viscous state B in which the thermosetting resin 4 is adhered and impregnated on the fiber base 3 is inserted between the pair of upper and lower corrugated gears 5 and the corrugated rack 6 of the corrugating apparatus 2 and pressed. Thus, corrugated from a sheet shape to a corrugated shape. In addition, as the corrugating apparatus 2, there is one using a pair of upper and lower gears.
Then, the corrugated prepreg 1 is supplied to a heating and pressing apparatus H such as a hot press while being held between the corrugated racks 6 and 7 as shown in FIG. 5 (2). As shown in FIG. 6 (1), the thermosetting resin 2 is brought into a completely cured state C to form a corrugated plate 8.

Then, as shown in FIG. 6B, the corrugated plate 8 is supplied between the print rolls 9, and the adhesive 10 is applied to the corrugated top surface and the bottom back surface. In the figure, 11 is a tray of the thermosetting adhesive 10, and 12 is a pick-up roll that is driven to rotate.
The corrugated plate 8 coated with the adhesive 10 is supplied to an oven or the like, heated and dried, and excess solvent in the adhesive 10 is evaporated and removed. Then, a plurality of corrugated plates 9 are stacked in a positional relationship in which the waveform is shifted by a half pitch and the top and bottom correspond to each other.
Then, as shown in FIG. 6 (3), the adhesive 10 supplied to a heating and pressing apparatus H such as an oven is melted and cured, so that it is in a completely cured state C. The stacked corrugated plates 8 are bonded by the agent 10.
In the conventional corrugated manufacturing method, by following such steps, as shown in FIG. 7, the corrugated plate 8 is used as the cell wall 13 and the cell 14 has a regular hexagonal cross section of a fiber reinforced plastic honeycomb. The core 15 was manufactured.

Examples of such conventional techniques include those disclosed in the following Patent Documents 1 and 2.
JP-A-11-300860 JP 2000-127271 A

"problem"
By the way, the following subject was pointed out about the manufacturing method of the honeycomb core 15 made from the fiber reinforced plastic which concerns on such a conventional corrugated system.
<First problem>
First, problems were pointed out in terms of cost. That is, in the conventional corrugated manufacturing method, first, the expensive corrugated molding apparatus 2 is indispensably used, which causes an increase in the manufacturing cost of the honeycomb core 15.
That is, for example, the corrugated gear 5 and the corrugated rack 6 and the pair of upper and lower gears of the corrugating apparatus 2 are used as a mold for continuously corrugating the prepreg 1, and precise and accurate dimension setting, meshing structure, position Matching, etc. was required, and the manufacturing cost was high and expensive.
Further, since the conventional manufacturing method uses the adhesive 10, the material cost is increased accordingly. Furthermore, it is indispensable to perform additional steps such as the application step, the drying step, and the heat curing step of the adhesive 10, and it takes time and effort for each step, resulting in an increase in manufacturing cost. .

<< Second problem >>
Secondly, it has been pointed out that it is difficult to produce a deformed honeycomb core. That is, the honeycomb core 15 is typically a cell wall 13 having a straight cell shape and a regular hexagonal shape of the cell 14 (see FIG. 7), but the cell wall 13 is bent and the cell 14 has a special shape. Honeycomb cores have also been developed and used (see Fig. 4 described later).
However, in the conventional corrugated manufacturing method, it has been difficult to manufacture the deformed honeycomb core.
That is, in the conventional corrugating apparatus 2 that uses the corrugated gear 5 and the corrugated rack 6 or a pair of upper and lower gears as the mold for continuous corrugating of the prepreg 1, the honeycomb core 15 that can be manufactured is limited. It was. The cell wall 13 is straight and the cell 14 is limited to a regular hexagonal shape, the cell wall 13 is bent, and the deformed honeycomb core made of fiber reinforced plastic having a special cell 14 shape has been difficult to manufacture.

《Third problem》
Thirdly, a problem has been pointed out that the honeycomb core 15 manufactured is likely to be thermally strained.
That is, in the conventional manufacturing method, heat curing is performed in the process of setting the prepreg 1 to the corrugated plate 8 in the fully cured state C and the process of setting the applied adhesive 10 to the fully cured state C, respectively. Therefore, the cell wall 13 made of fiber reinforced plastic, that is, the corrugated plate 8 made of prepreg 1 that has been completely cured, is likely to generate thermal strain based on the thermal history due to the accumulation of heat curing.
The honeycomb core 15 is made of two different materials, and the cell wall 13, that is, the corrugated plate 8 portion and the adhesive 10 portion have different amounts of thermal deformation and thermal expansion and contraction. Distortion was easy to occur.

《Fourth problem》
Fourthly, the manufactured honeycomb core 15 has also been pointed out to be heavy.
That is, the fiber-reinforced plastic honeycomb core 15 manufactured by the conventional manufacturing method is bonded by the adhesive 10 between the corrugated plates 8 forming the cell walls 13. It was pointed out that the lightness was impaired.

<< About the present invention >>
In view of such circumstances, the method for manufacturing a fiber-reinforced plastic honeycomb core of the present invention has been made to solve the above-described problems of the prior art.
The present invention is firstly cost-effective, secondly capable of producing a deformed honeycomb core, thirdly, no thermal strain is generated, and fourthly, a corrugated system in which the weight is reduced. An object of the present invention is to propose a method for manufacturing a honeycomb core made of fiber reinforced plastic.

<About each claim>
The technical means of the present invention for solving such a problem is as follows, as described in the claims.
About Claim 1, it is as follows.
In the method for manufacturing a honeycomb core made of fiber reinforced plastic according to the first aspect of the present invention, a number of piece members corresponding to the cell shape of the honeycomb core are used, and the piece member groups are stacked with a prepreg interposed therebetween.
Then, each of the interposed prepregs is completely cured by heating and pressurizing and bonded to each other, and then the piece of each piece of the piece member group is removed to remove the honeycomb core made of fiber reinforced plastic. It is characterized by obtaining.

About Claim 2, it is as follows.
A method for manufacturing a honeycomb core made of fiber reinforced plastic according to claim 2 is the method for manufacturing a honeycomb core made of fiber reinforced plastic according to claim 1, comprising a planar aggregate of a plurality of hollow columnar cells partitioned by cell walls. To do.
And it has the following preparatory process, an accumulation setting process, a corrugation process, a heating, a pressurization process, a final process, etc., It is characterized by the above-mentioned.
In the preparation step, a plurality of prepregs in a viscous state in which a thermosetting resin is attached and impregnated on a fiber base material, and a plurality of top members having shapes corresponding to the cells are prepared.
In the stack setting step, a group of the piece member groups are arranged side by side, and then the other group of the piece member groups are sequentially stacked on the piece member group.
In the corrugating process, in the stacking setting process, the prepregs are sequentially placed between the stacked member pieces, and each corrugated shape in which corrugated irregularities are continuously formed. It will be bent.
In the heating and pressurizing step, the entire thermosetting resin and each of the prepregs are completely cured by heating and pressurizing the whole, and the corresponding top and bottom portions of the corrugated prepregs are joined to each other. To do.
In the final step, all the top members of each of the top member groups are extracted and removed to obtain the honeycomb core in which the cell walls made of fiber-reinforced plastic are formed by the prepreg.

About Claim 3, it is as follows.
The method for manufacturing a honeycomb core made of fiber reinforced plastic according to claim 3 is characterized in that, in claim 2, the cell wall, the cell, and the top member have a regular hexagonal cross-sectional shape.
About Claim 4, it is as follows.
In the method for manufacturing a fiber-reinforced plastic honeycomb core according to claim 4, the lowermost and uppermost coma member groups stacked in claim 3 include the coma member having a semi-hexagonal cross section. It is characterized by.
About Claim 5, it is as follows.
In the method for manufacturing a fiber-reinforced plastic honeycomb core according to a fifth aspect of the present invention, in the third aspect, a corrugated rack is used instead of the top member group for the lowermost and uppermost stacked layers. The corrugated rack has a corrugated surface in which corrugated irregularities having a semi-hexagonal cross section are continuously formed.

<About the action>
Since the present invention comprises such means, the following is achieved.
(1) The manufacturing method of the present invention manufactures a honeycomb core made of fiber reinforced plastic by following the steps of preparation, stacking set, corrugation, heating, pressurization, final, and the like.
(2) That is, first, a prepreg is prepared in a sheet-like viscous state, and a coma member having a shape corresponding to the cell is prepared.
(3) The top member groups are stacked, and the prepregs are placed between the stacked top member groups, respectively, and bent into a corrugated shape.
(4) Then, the prepreg is completely cured by heating and pressurizing, and the top portion and the bottom portion of the prepreg, which are corrugated and contact each other, are joined.
(5) After that, all the top member groups are extracted and removed.
(6) By following such a process, a honeycomb core made of fiber reinforced plastic is manufactured.
(7) Since the manufacturing method of the present invention is as described above, it is as follows. First, a piece member is used for corrugating, and expensive corrugating devices such as gears and racks are not used. In addition, since no adhesive is used, the material cost is reduced, and steps such as application, drying, and heat curing of the adhesive are not required.
(8) Further, a prepreg is corrugated using a piece having a shape corresponding to the cell, and a honeycomb core is manufactured. Therefore, a deformed honeycomb core having a curved cell wall and a special cell shape can be manufactured.
(9) Heat curing is performed only once in the heating and pressurizing steps, and the heat history of heat curing is uniform for cell walls made of prepreg, that is, fiber reinforced plastic. Further, since no adhesive is used, the cell wall is made of a single material of prepreg, that is, fiber reinforced plastic, and the amount of thermal deformation is not partially different. As a result, thermal strain does not occur in the manufactured honeycomb core.
(10) Since the prepreg is completely cured and the prepregs, that is, the cell walls, are joined and no adhesive is used, the weight of the manufactured honeycomb core is reduced accordingly.
(11) Now, the production method of the present invention exhibits the following effects.

<< First effect >>
First, it is excellent in cost. In the method for manufacturing a honeycomb core made of fiber reinforced plastic according to the present invention, a top member is used, and the prepreg is corrugated by stacking the top member group while interposing the prepreg.
That is, like this type of prior art, since an expensive corrugated molding device combining gears, racks, etc. is not used as a continuous molding die, the manufacturing cost of the honeycomb core made of fiber reinforced plastic by the corrugated system is It is greatly reduced.
Further, since the adhesive is not used as in this type of prior art, the material cost is reduced accordingly. Furthermore, the additional steps associated with the use of the adhesive are not required, and the manufacturing process is simplified correspondingly, thereby reducing the manufacturing cost from this aspect.

<< Second effect >>
Second, a modified honeycomb core can also be manufactured. In the method for manufacturing a fiber-reinforced plastic honeycomb core of the present invention, a honeycomb core is manufactured using a piece member. Therefore, a deformed honeycomb core made of fiber reinforced plastic having a curved cell wall and a special cell shape can be easily manufactured by the corrugated method.
That is, unlike this type of prior art described above, a corrugated molding device combining a gear and a rack is not used as a continuous molding die, so that the cell wall is limited to a honeycomb core such as a straight hexagonal cell. It is also possible to manufacture a deformed honeycomb core.

《Third effect》
Third, no thermal distortion occurs. In the method for manufacturing a fiber-reinforced plastic honeycomb core of the present invention, heat curing is performed only once, and the heat history of heat curing is uniform for the prepreg, that is, the cell wall. Therefore, thermal distortion does not occur in the manufactured honeycomb core.
In addition, the honeycomb core is manufactured using only the prepreg of fiber reinforced plastic, and the adhesive is not used as in the prior art of this kind, and all are made of the same material. There is no difference in the amount of thermal deformation. Therefore, thermal distortion does not occur from this aspect.

<< 4th effect >>
Fourth, the weight of the honeycomb core is reduced. In the method for manufacturing a honeycomb core made of fiber reinforced plastic according to the present invention, the prepregs interposed between the top member groups are completely cured by heating and pressurizing and are joined together.
That is, since no adhesive is used as in this type of prior art, the weight of the manufactured honeycomb core is reduced accordingly.
As described above, the effects exerted by the present invention are remarkably large, such as all the problems existing in this type of conventional example are solved.

The method for manufacturing a fiber-reinforced plastic honeycomb core according to the present invention will be described for explaining the mode for carrying out the invention. And (1) figure shows a preparatory process and is a perspective view of the prepared prepreg. (2) The figure shows a preparatory process and an accumulation setting process, and is a perspective view of a piece member and a piece member group. (3) The figure shows a stacking set process and a corrugating process, and is a perspective view of a piece member group and a prepreg. It serves for description of the form for implementing this invention. And (1) is a perspective view of a top member group and a prepreg, showing the stacking setting process and the corrugating process. (2) The figure shows a stacking setting process and a corrugating process, and is a front view of a piece member group and a prepreg. (3) The figure shows a heating and pressurizing process and is a front view of a heating and pressurizing apparatus and the like. It serves for description of the form for implementing this invention. And (1) figure shows the final process and is a front view of the manufactured honeycomb core, and (2) figure is the perspective view. It serves for description of the form for implementing this invention. (1) is a front view of an example of a modified honeycomb core, and (2) is a front view of another example. A description will be given of a method for manufacturing a honeycomb core made of fiber reinforced plastic according to the prior art. (1) is a perspective view of the corrugating process, and (2) is a perspective view of the heating and pressurizing process. A description will be given of a method for manufacturing a honeycomb core made of fiber reinforced plastic according to the prior art. (1) is a perspective view of the corrugated plate, (2) is a front view of the adhesive application step, and (3) is a front view of the heating and pressurizing step. A description will be given of a method for manufacturing a honeycomb core made of fiber reinforced plastic according to the prior art. And it is a front view of the manufactured honeycomb core.

Hereinafter, embodiments for carrying out the present invention will be described in detail.
<< Outline of the Present Invention >>
First, the outline | summary of this invention is demonstrated with reference to FIGS. 1-3.
The manufacturing method of the fiber reinforced plastic honeycomb core 16 of the present invention uses a number of pieces 17 corresponding to the cell shape of the honeycomb core 16.
After the top member groups 18 are stacked with the prepregs 19 interposed therebetween, the interposed prepregs 19 are completely cured and joined together by heating and pressing, and then the top member groups 18 are joined. The honeycomb core 16 is obtained by removing the 18 piece members 17.
That is, the honeycomb core 16 made of fiber reinforced plastic, which is composed of a planar assembly of a large number of hollow columnar cells 21 partitioned by the cell walls 20, is manufactured. Therefore, the present invention is characterized in that the preparation process, the stacking setting process and the corrugating process, the heating, the pressurizing process, the final process and the like are sequentially followed.
Hereinafter, each of these steps will be described.

About the preparation process
First, a preparation process is demonstrated with reference to the (1) figure of FIG. 1, (2) figure.
In this manufacturing method, a plurality of prepregs 19 in a viscous state B in which the thermosetting resin 4 is adhered and impregnated on the fiber base material 3 and the cells 21 of the honeycomb core 16 are formed in the preparation step. A top member 17 is prepared.
Such a preparation process will be further described in detail.

First, the prepared prepreg 19 will be described. As the fiber base 3 of the prepreg 19, carbon fibers, glass fibers, Kepler fibers, ceramic fibers, metal fibers, resin fibers, and other various woven / nonwoven or organic / inorganic fibers can be used. It is appropriately selected and used from among fibers having strength and high rigidity. Of course, unidirectional fibers and non-crimp weaves can also be used.
As the thermosetting resin 4, a cyanate resin, an epoxy resin, a polyimide resin, a phenol resin, and other thermosetting resins are selectively used.
Then, a prepreg 19 in which the thermosetting resin 4 in the viscous state B is combined and combined with the fiber base material 3 by adhesion, impregnation, mixing, or the like is prepared in the viscous state B. The prepreg 19 has an extremely thin and flat film shape and sheet shape, and the thermosetting resin 4 has a tacky, sticky, flexible, flexible, and deformable viscous state B, It is prepared in a so-called B stage state.
First, one prepreg 19 is generally formed by attaching, impregnating, and mixing the thermosetting resin 4 to one fiber base material 3, but using a plurality of fiber base materials 3. It is also possible. That is, it is also possible for one prepreg 19 to be formed by attaching, impregnating, and mixing the thermosetting resin 4 to a plurality of fiber bases 3 such as two.
Secondly, the prepreg 19 is typically one in which the thermosetting resin 4 is adhered, impregnated, and mixed into the fiber base material 3, but the fiber base material 3 is not limited to this, for example, a sulfone resin. , Other thermoplastic resins can be attached, impregnated and mixed. In this case, it is completely cured by natural cooling after heating.

Next, the top member 17 to be prepared will be described. As the material of the top member 17, iron, aluminum, other metals, plastics such as thermosetting resin and thermoplastic resin, fiber reinforced plastic (FRP), and the like can be considered.
The shape of the piece member 17 includes various shapes corresponding to the cells 21 of the honeycomb core 16 to be manufactured. In the illustrated example, as a representative example, a frame member 17 having a regular hexagonal cross-sectional shape is used. Note in the illustrated example, as the least significant frame member group 18 ₁ and the top-level frame member group 18 is the stacking, as described below, have also been used sectional half hexagonal frame member 17.
The outer surface of the piece member 17 is subjected to a mold release process, but the piece member 17 itself may be made of a releasable material. The release treatment and release property of the top member 17 stick to the prepreg 19 in the viscous state B and do not exhibit the release effect, but release from the prepreg 19 in the fully cured state C. Demonstrate the effect.
A large number of such piece members 17 are prepared. For example, when manufacturing a honeycomb core 16 having a regular hexagonal cell size of 3/8 inch (9.5 mm) and a length and width of 15 cm, about 250 piece members 17 are prepared.
The preparation process is as described above.

《About stack setting process》
Next, the stacking setting step will be described with reference to FIGS. 1 (2), 3 (3), 2 (1), 2 (2) and the like.
In intussusception setting step of this manufacturing method, the number of piece member 17 prepared in the preparation step described above, first, a group of the frame member group 18 _1, from side-by-side, on the frame member group 18 ₁ and stacking the other group of piece member group 18 _2. Then, on the frame member group 18 ₂ which is a heavy product, further Juseki other group of frame member group 18 _3, posterior likewise sequentially going to Juseki the frame member group 18.

Such an accumulation setting process will be further described in detail. First, the top member 17 is preheated when used in such an accumulation setting step. That is, a prepreg 19 having a waist and a viscous state B is interposed between the stacked top members 17 as described later.
The prepreg 19 interposed in this manner is necessary from the piece member 17 that has been heated in advance so that it has the necessary flexibility, flexibility, and deformability, that is, can be bent into a corrugated shape. A proper amount of heat is transmitted to the prepreg 19. Accordingly, the top member 17 is heated to a level necessary and sufficient for such heat transfer and is used.

Now, as shown in (2) view of FIG. 1, in this stacking setting step, first, a group of frame member group 18 ₁ on the horizontal surface is, as the least significant frame member group 18 _1, the waveform on the upper surface They are arranged side by side to form irregularities.
In the illustrated example, the frame member group 18 ₁ of this lowest, (further also applies to the frame member group 18 of the top-level) and cross-section a regular hexagonal frame member 17, a cross-sectional semi-hexagonal frame member 17 Are arranged in a positional relationship that is alternately and densely arranged horizontally. The lowermost (or uppermost) top member group 18 is not limited to the illustrated example, and the following first, second, and third configurations are possible.
First, only the piece members 17 having a semi-hexagonal cross section may be arranged side by side at the same height level on the horizontal plane while being positioned so as to have a constant pitch interval.
Secondly, only the piece members 17 having a regular hexagonal cross section may be arranged side by side while being positioned so that the height levels thereof are alternately different from each other and the upper and lower steps and irregularities of a constant pitch are generated. .
Third, it is possible to use a corrugated rack in place of such a piece member group 18. That is, a corrugated rack may be used in place of the top member 17, and the corrugated rack used in this way has a corrugated surface on which corrugated irregularities having a semi-hexagonal cross section are continuously formed.

Then the stacking setting process, the (1) 2 as shown in FIG, on such a lowest ordered next frame member group 18 _1, the following other group of frame member group 18 ₂ are stacked.
That is, as described with reference to (3) FIG etc. Figure 1 in the next corrugation step, on the lowest frame member group 18 _1, first prepreg 19 is placed on top of the prepreg 19, the following another group of frame member group 18 ₂ is intussusception.
The intussusception of the following other group of frame member group 18 _2, as shown in (1) view of FIG. 2, each formed at the bottom of the frame member group 18 ₁凹上, each frame member 17 forming the frame member group 18 _2, to rest tightly through the prepreg 19, it is performed. In contrast, on the convex formed at the bottom of the frame member group 18 _1, frame member 17 forming the frame member group 18 ₂ it is not placed.
Have been, between each frame member 17 forming the frame member group 18 _2, a gap of a constant pitch in the lateral direction, respectively, are formed.
And after the fact, by repeating such a stacking step, as shown in FIG. 2 (2), the top member groups 18 ₁ , 18 ₂ , 18 ₃ , 18 ₄ , via the prepreg 19 respectively. 18 ₅ ,... Are stacked to reach the uppermost frame member group 18.
The stacking process is as described above.

About the corrugating process
The corrugating process will be described with reference to FIG. 1 (3), FIG. 2 (1), and FIG. 2 (2).
The corrugating process of this manufacturing method is performed in parallel with the above-described stack setting process. Then, the prepregs 19 are sequentially placed between the stacked top member groups 18 and interposed, and each of the interposed prepregs 19 is bent into a corrugated shape in which corrugated irregularities are continuously formed, Corrugated.

Such a corrugating process will be further described in detail. In the above-described stack setting step, the respective frame member groups 18 are sequentially stacked. At this time, between the respective frame member groups 18 that are stacked in this way, FIG. As shown in FIGS. 2 (1) and 2 (2), the prepreg 19 is placed and set in an intervening manner.
That is, in this manufacturing method, the stack setting process and the corrugation process are alternately performed in sequence, and the prepreg 19 is placed and interposed for each stack of the piece member group 18.
The number of the prepregs 19 placed and interposed in this way is often one, as shown in the figure, but it is also possible to make a plurality of sheets, such as two, irrespective of the figure. That is, it is also conceivable that a plurality of prepregs 19 are placed between each piece member group 18 and placed.
Further, the prepreg 19 is provided with release sheets such as vinyl sheets on both upper and lower surfaces. When the prepreg 19 is placed and interposed in such a manner, the release sheets are removed.

Now, the prepreg 19 mounted and interposed in this way is flexible, flexible, and deformable based on its viscous state B, and is pressurized based on the mass of the top member group 18 stacked above it. Is bent from a sheet shape to a corrugated shape.
That is, as shown in FIGS. 2 (1) and 2 (2), each prepreg 19 in the viscous state B has a corrugated shape in which corrugated irregularities are continuously formed at a predetermined pitch and height. It is bent. The prepreg 19 is sandwiched between the upper and lower frame member groups 18 and is pressed and pressed to be corrugated.
And each corrugated prepreg 19 is in a positional relationship in which the top and bottom correspond to each other between the upper and lower sides.
The corrugating process is as described above.

<< About heating and pressurizing processes >>
Next, the heating and pressurizing steps will be described with reference to FIG.
In the heating and pressurizing process of this manufacturing method, the viscous thermosetting resin 4 and the prepreg 19 are completely cured by heating and pressurizing the whole after the above-described stack setting process and corrugating process, The top and bottom portions of the corrugated prepregs 19 that contact each other are joined.

Such heating and pressurizing steps will be described in further detail. The block body 22 obtained by the stack setting process and the corrugation process described above, that is, the block body 22 formed by an assembly of the stacked top member groups 18 and the prepreg 19 interposed therebetween is shown in FIG. ) As shown in FIG.
The heating / pressurizing device H includes a hot press, a hot-air oven, an induction heating furnace, and the like, and is heated at a high temperature with the degree of curing of the thermosetting resin 4 while uniformly pressing the prepreg 19 of the block body 22 by applying a certain amount of vertical pressure. To do.
As a result, the thermosetting resin 4 of the prepreg 19 that was in the viscous state B of the B stage is completely cured and solidified into the fully cured state C of the C stage. And in the case of such complete hardening, the top part and the bottom part which were correspondingly overlapped and contacted between each prepreg 19 are reliably joined using the melt hardening of the thermosetting resin 4. FIG.
In other words, when the block body 22 is observed except for the top member group 18, the corrugated upper and lower prepregs 19 are sequentially shifted in the left and right by half a pitch, so that the top (peak) and bottom (valley) Are in contact with each other in the corresponding vertical relationship.
Therefore, the top portion and the bottom portion of the prepreg 19 are joined by heating and pressurization, respectively.
The heating and pressurizing processes are as described above.

《About the final process》
Next, the final process will be described with reference to FIGS. 3A and 3B.
In the final step of this manufacturing method, after the heating and pressurizing steps described above, the cell wall members 20 made of fiber reinforced plastic were formed with the fully cured prepreg 19 by extracting and removing all the piece members 18. A honeycomb core 16 is obtained.
That is, all the piece members 17 forming each piece member group 18 are removed from the block body 22, that is, from the block piece 22 that is an assembly of the prepreg 19 that is corrugated and completely cured with each piece member group 18. Issued and removed.
Accordingly, as shown in FIG. 3, the honeycomb core 16 is obtained from the remaining prepreg 19. A honeycomb core comprising a corrugated prepreg 19 in a completely cured state C as a cell wall 20 and a planar aggregate of a number of hollow columnar cells 21 each defined by a cell wall 20 made of fiber reinforced plastic. 16 is manufactured.
The final process is as described above.

<< About the honeycomb core 16 made of fiber reinforced plastic >>
The honeycomb core 16 made of fiber reinforced plastic shown in FIG. 3 is manufactured by following the preparation process, the stack setting process, the corrugation process, the heating, the pressing process, and the final process.
The cross-sectional shape of the cell wall 20 and the cell 21 of the honeycomb core 16 is typically the regular hexagonal shape shown in the figure, but is not limited to this, it may be a substantially triangular shape, a substantially rectangular shape, or other various shapes. For example, the modified honeycomb core 16 described below is also possible.
The honeycomb core 16 made of fiber reinforced plastic is excellent in weight specific strength (compressive strength in the cell axis direction), is lightweight, and has high strength and rigidity, like a general honeycomb core.
In addition, it has excellent flatness (especially when used as a honeycomb sandwich panel with surface plates bonded to both opening end faces), rectification effect, heat retention, etc., and has a large surface area per unit volume. Are known. Furthermore, it has excellent corrosion resistance. Therefore, it is widely used as various structural materials.
When the manufactured fiber reinforced plastic honeycomb core 16 is required to have further rigidity and strength, a reinforcing resin is additionally attached and impregnated to the cell wall 20 as a post-treatment.
As the reinforcing resin, a resin according to the above-described thermosetting resin 4 is used. After the honeycomb core 16 is immersed in a bathtub in which the reinforcing resin is stored, the honeycomb core 16 is taken out and dried, and then adhered and impregnated. The cured reinforcing resin is heated and cured in an oven or the like. Accordingly, the honeycomb core 16 is reinforced.
The honeycomb core 16 made of fiber reinforced plastic is as described above.

<About the irregular honeycomb core 16>
Here, the deformed honeycomb core 16 will be described with reference to FIG. 4 (1), (2) and the like.
The honeycomb core 16 is typically one in which the cell walls 20 are linear and the cross-sectional shape of the cells 21 is, for example, a regular hexagon (see FIGS. 3A and 3B). . On the other hand, a deformed honeycomb core 16 in which the cell wall 20 is curved without forming a straight line and the cross-sectional shape of the cell 21 is specially developed and used according to needs.
That is, in order to meet the need for curved surfaces rather than the general flat plate needs, the deformed honeycomb core 16 is easy to torsional deformation and curved surface processing from flat plates to secondary curved surfaces and cubic curved surfaces. Developed and used.
In this modified honeycomb core 16, the cross-sectional shape of the cell 21 has a rounded special substantially convex shape. And the thing of the (1) figure of FIG. 4 is called a flexible core, and the cell wall 20 is curving concavely or convexly at one place in the middle. 4 (2) is called a double flexible core, and the cell wall 20 is bent inward and outward in a concave and convex manner on the way.
Such a deformed honeycomb core 16 can also be easily manufactured by the manufacturing method of the present invention. That is, by manufacturing and preparing in advance the piece member 17 corresponding to the shape of the cell 21 of the deformed honeycomb core 16 to be manufactured, and after that, by following the above-described steps, the deformed honeycomb core 16 is formed. Manufactured.
The modified honeycomb core 16 is as described above.

《Action etc.》
The manufacturing method of the present invention is configured as described above. Then, it becomes as follows.
(1) The manufacturing method of the present invention manufactures the honeycomb core 16 made of fiber reinforced plastic by sequentially following the preparation process, the stack setting process and the corrugating process, the heating, the pressurizing process, the final process, and the like.

(2) That is, in the preparation step, a fiber reinforced plastic prepreg 19 in which the thermosetting resin 4 is adhered and impregnated to the fiber base 3 is prepared in a sheet-like viscous state B (FIG. 1 (1) diagram). See).
At the same time, a large number of piece members 17 having a shape corresponding to the cells 21 of the honeycomb core 16 to be manufactured are prepared (see FIG. 1B).

(3) First, the stack setting process and the corrugation process are alternately performed. That is, the prepregs 19 are respectively placed and interposed between the top member groups 18 that are stacked and set (see FIG. 1 (3)).
Then, the prepreg 19 mounted and interposed is bent into a corrugated shape (see FIGS. 2A and 2B).

  (4) Then, the process proceeds to the heating and pressurizing steps, and the thermosetting resin 4 and the prepreg 19 in the viscous state B, which have been corrugated, are cured into the completely cured state C. Along with this, the top portion and the bottom portion corresponding to each other on the upper and lower sides of the prepreg 19 are joined to each other (see FIG. 2 (3)).

  (5) Then, in the final step, the prepreg 19 is left, and all the piece members 17 of each piece member group 18 are extracted and removed (see FIG. 3A).

(6) By following each of these steps, a cell wall 20 made of fiber-reinforced plastic is formed in the fully cured corrugated prepreg 19.
Thus, a honeycomb core 16 made of fiber reinforced plastic made of a planar assembly of cells 21 partitioned by the cell wall 20 is manufactured (see FIGS. 3A and 3B). .

(7) The manufacturing method of the honeycomb core 16 of the present invention is as described above. Therefore, it becomes as follows.
First, in the manufacturing method of the present invention, a large number of piece members 17 are used, and the piece member groups 18 are stacked with the prepreg 19 interposed therebetween, whereby the prepreg 19 is corrugated (see (1 in FIG. 2). ) See Figure, (2) Figure, etc.).
The prepreg 19 is not necessarily corrugated using the expensive corrugating apparatus 2 combined with gears, racks, etc. (FIG. 5 (1), (2), FIG. 6 (1), etc.) See the prior art). Therefore, the manufacturing cost of the manufacturing method of the present invention is reduced.
Further, in the manufacturing method of the present invention, the corrugated prepregs 19 are not bonded using the adhesive 10 (FIG. 6, (2), (3), FIG. 7 and the like). (See the technology), joining using the fully cured state C of the prepreg 19 itself (see FIG. 2 (3)).
Since the adhesive 10 is not used in this way, the application process of the adhesive 10 (see the prior art in FIG. 6 (2)), the drying process of the applied adhesive 10, the heating of the dried adhesive 10, Additional implementations and additional implementations of laborious processes such as the curing process (see the prior art in FIG. 6 (3)) are unnecessary.
Therefore, the manufacturing method of the present invention has a simple process, and the manufacturing cost is reduced also from this aspect. Further, since the adhesive 10 is not used, the material cost is also reduced.

(8) In the manufacturing method of the present invention, the honeycomb core 16 is manufactured using the top member 17 having a shape corresponding to the cell 21.
Therefore, by preparing and preparing in advance the piece member 17 having a shape corresponding to the cell 21 of the honeycomb core 16 to be manufactured, it is possible to deal with various shapes. Therefore, the deformed honeycomb core 16 in which the cell wall 20 is bent and the cell has a special cross-sectional shape can be easily manufactured.

(9) In the manufacturing method of the present invention, the prepreg 19 is heat-cured only once in the heating and pressurizing steps (see FIG. 2 (3)). That is, heat curing is not performed a plurality of times (FIG. 5 (2), FIG. 6 (3) compared with the prior art in FIG. 6).
Therefore, the thermal history of heat curing is uniform for the prepreg 19 and the cell wall 20, and there is no change in the physical properties thereof. Therefore, thermal distortion does not occur in the honeycomb core 16 manufactured by the manufacturing method of the present invention.
Further, since the adhesive 10 is not used as described above, the manufactured honeycomb core 16 is entirely made of the same material. All are made of a single material of fiber reinforced plastic, and the adhesive 10 which is a different material is not used (the honeycomb core 16 of the present invention in FIG. 3 is compared with the honeycomb core 15 in the prior art in FIG. 7). Control).
In the honeycomb core 16 manufactured by the manufacturing method of the present invention, since the cell wall 20 is made of a single material as described above, the amount of thermal deformation is not partially different, and the entire core core 16 is expanded and contracted by the same amount. However, thermal distortion does not occur from this surface.

(10) In the manufacturing method of the present invention, the cell walls 20 are joined together by completely curing the prepreg 19 in the viscous state B.
The corresponding top and bottom of the corrugated prepreg 19 are joined using the fully cured state C of the prepreg 19 itself. Adhesive 10 is not used for bonding (the honeycomb core 16 of the present invention in FIG. 3 and the prior art honeycomb core 15 in FIG. 7 are comparative).
Therefore, the weight of the honeycomb core 16 manufactured by the manufacturing method of the present invention is reduced by the amount not using the adhesive 10.
As for the action, it is as above.

1 Prepreg (conventional example)
DESCRIPTION OF SYMBOLS 2 Corrugating apparatus 3 Fiber base material 4 Thermosetting resin 5 Corrugated gear 6 Corrugated rack 7 Corrugated rack 8 Corrugated board 9 Print roll 10 Adhesive 11 Tray 12 Pickup roll 13 Cell wall (conventional example)
14 cells (conventional example)
15 Honeycomb core (conventional example)
16 Honeycomb core (present invention)
17 top member 18 top member group 18 ₁ , 18 ₂ , 18 ₃ , 18 ₄ , 18 ₅
Top member group 19 Prepreg (present invention)
20 cell wall (present invention)
21 cells (present invention)
22 Block body B Viscous state C Completely cured state H Heating and pressing device

Claims (5)

Use a number of piece members suitable for the cell shape of the honeycomb core, and stack the piece member groups with the prepreg interposed therebetween.
By heating and pressurizing, each of the interposed prepregs is completely cured and joined together, and then removing the piece members of each piece member group,
A method for producing a honeycomb core made of fiber reinforced plastic, comprising obtaining the honeycomb core made of fiber reinforced plastic. The method of manufacturing a honeycomb core made of fiber reinforced plastic according to claim 1, comprising a planar assembly of a large number of hollow columnar cells partitioned by cell walls.
A preparatory step of preparing a plurality of the prepregs in a viscous state in which a thermosetting resin is adhered and impregnated on a fiber base material, and a plurality of the top members having shapes corresponding to the cells;
A stack setting step in which a group of the piece member groups are arranged side by side, and the other piece of the piece member groups are sequentially stacked on the piece member group;
During the stacking setting step, the prepregs are sequentially placed between the stacked member groups, and each prepreg is bent into a corrugated shape in which corrugated irregularities are continuously formed. Corrugating process,
Then, the thermosetting resin and each of the prepregs are completely cured by heating and pressurizing the whole, and the heating and pressurizing steps for joining the corresponding top and bottom of the corrugated prepregs to each other. When,
A final step of obtaining the honeycomb core in which the cell walls made of fiber-reinforced plastic are formed in the completely cured prepreg by extracting and removing all the top members of each of the top member groups;
A process for producing a honeycomb core made of fiber reinforced plastic, comprising:   3. The method for manufacturing a fiber reinforced plastic honeycomb core according to claim 2, wherein the cell wall, the cell, and the top member have a regular hexagonal cross-sectional shape.   4. The method for manufacturing a fiber reinforced plastic honeycomb core according to claim 3, wherein the lowermost and uppermost coma member groups stacked include the coma member having a semi-hexagonal cross section. In claim 3, for the lowest and highest positions stacked, a corrugated rack is used instead of the top member group,
The corrugated rack includes a corrugated surface in which corrugated irregularities having a semi-hexagonal cross section are continuously formed.

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