JP2000167632A - Sandwich structure plate and manufacture of the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a sandwich structure plate having higher rigidity strength than a zeta-core sandwich structure plate which has a flow passage formed in the interior though. SOLUTION: This sandwich structure plate has a core material 1 of the shape of MIURA folding and two sheets of metal plates 2 joined by seam welding respectively to chevron fold parts on both sides of the core material 1. Different from a zeta-core, the core material 1 has no summit surface, so the rate of effective part as a core material gains so mush, and rigidity strength gets higher than a zeta-core sandwich structure plate even though a flow passage in the interior is formed. This sandwich structure plate is continuously mass produced through a core material forming process in which a metallic flat plate is formed into a core material 1 in the shape of MIURA folding and a joining process in which two sheets of metal plates 2 are seam welded in a zigzag form on both sides of chevron fold parts of the core material 1.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] The present invention belongs to the technical field of sandwich structure plates. The sandwich structure plate of the present invention can be used not only as a structural material but also as a functional material having a function such as heat exchange.

[0002]

2. Description of the Related Art Miura folding has been studied as a beautiful buckling mode that occurs when compressive stress is applied to an infinitely wide plane material from front, rear, left and right. Miura folding is capable of compactly folding a flat surface, and is easily extended uniformly from the folded state, so that it is expected to be applied to space structures such as vast solar cell plates. At the Space Flyer, an unmanned space laboratory at the Institute of Space and Astronautical Science, an experiment to extend a large-area solar cell panel folded by Miura folding in space has been successfully performed.

[0003] Miura folding is also known as special origami paper, and has an application as a folded shape of a map. However, the inventors do not know about the application as a structural material. As a prior art closest to the present invention, a sandwich structure plate has been announced as an alternative to the honeycomb sandwich structure plate by the professor emeritus of the Institute of Space and Astronautics, Miura, who discovered Miura folding ("New Stract").
ural Form of Sandwich Core ", Journalof AIRCRAFT, V
ol. 12, No. 5, pp. 437-441, May 1975, American Instit
ute of Aeronautics and Astronautics). For this sandwich structure plate, a three-dimensional corrugated press-formed plate named zeta core is used as the core material, and the plate material is joined to both sides of the zeta core to form a plate-like sandwich structure plate ing. The publication discloses the results of analysis on the rigidity, shear strength, and the like of a sandwich structure plate using a zeta core, and reveals that a rigid strength equivalent to that of the honeycomb core sandwich structure plate can be obtained. It also discloses that a flow path is formed inside, unlike the honeycomb sandwich structure plate.

[0004] The zeta core has a shape different from that of Miura folding, and a zigzag top surface is formed at the top of both surfaces. Then, by applying an adhesive to the top surface, two plate members are joined to both sides of the zeta core. This top surface is required not only for bonding by bonding the zeta core and the two plates, but also for providing a relief in plastic working when the zeta core is formed from a flat plate by pressing. You. That is, according to the above-mentioned publication, in press forming of a metal material such as ductile aluminum, in order to form a zeta core with a sufficiently deep bending angle, it is hardly possible to work without this top surface. In other words, it is difficult to form a Miura-folded core by ordinary press-forming, and by forming a zeta core instead of forming a Miura-folded core material, it is possible to perform press-forming processing. It is possible.

[0005]

As described above, the top surfaces on both sides of the zeta core are not only necessary for pressing the core material from a flat plate but also for bonding the core material and the plate materials on both sides. It was also required as an adhesive surface for bonding. However, the top surfaces on both sides of the zeta core do not contribute to the rigidity and strength as the core material, and only function as an adhesive surface except that press molding is facilitated. Therefore, if a flat plate can be formed into a Miura-folded core material by some processing means, almost all portions of the core material contribute to the rigidity and strength of the core material. In addition, if instead of the top surfaces on both sides of the zeta core, it is possible to sufficiently firmly join the plate material at the mountain-folded portions on both sides of the Miura-folded core material, a strong sandwich structure plate can be formed.

Accordingly, an object of the present invention is to provide a sandwich structure plate having higher rigidity and strength than a sandwich structure plate having a zeta core. Another object of the present invention is to provide a manufacturing method capable of manufacturing such a sandwich structure plate.

[0007]

(Invention of an object) A sandwich structure plate of the present invention comprises a core material having a Miura folded shape,
And two plate members respectively joined to the mountain folds on both sides of the core material. Here, the Miura-folded shape means, as shown in an example of a development view in FIG. 1, a plane which is congruent or inverted and leaves a congruent parallelogram plane, and each side of each parallelogram is regularly mountain-folded. Or it is a three-dimensional corrugated sheet shape obtained by valley folding. The length ratio and the angle between the sides of these parallelograms can be arbitrarily determined as design items. In the above, the Miura fold shape was described by comparing it to origami, and it was described that there was no in-plane deformation of each parallelogram.However, when manufacturing the core material of the Miura fold shape, The quadrilateral may be expanded and contracted.

[0008] Usually, an appropriate radius is formed on the outside of the mountain-folded portion on both sides of the core material having such a Miura-folded shape. The plate material is bonded to the outside of such a mountain-folded portion of the core material, and the core material and the two plate materials sandwiching the core material are integrally fixed to form a single sandwich structure plate. As a method for joining the mountain-folded portion of the core material and the plate material, resistance welding, brazing, adhesion, and the like can be considered, but any joining method may be used as long as the joining can be performed sufficiently firmly.

[0009] The sandwich structure plate constructed as described above has no top surface, and almost all of the core material is a parallelogram portion, as compared with the prior art using a zeta core as a core material. Therefore, the ratio of the effective portion as the core material that connects and fixes the two plate materials on both sides to each other is high, and the core material connects the two plate materials more densely.
The rigidity of the present invention is increased as compared with the prior art.

Therefore, according to the sandwich structure plate of the present invention, there is an effect that the rigidity is higher than that of the sandwich structure plate using the zeta core of the prior art as a core material. Also, unlike the honeycomb sandwich structure plate, the flow path is formed inside similarly to the prior art,
There is an effect that it can be used as a heat exchanger like a cooler or a radiator while having a function as a structural member. Alternatively, since the internal flow path is divided into a plurality of parts, there is an effect that two kinds of fluids can be flowed to the other side every other one, and heat exchange can be performed between the two fluids.

Further, in the sandwich structure plate of the present invention, the core material and the two plate materials are each made of a metal material, and the core material and the two plate materials are respectively joined by resistance welding. . In the sandwich structure plate having such a configuration, the joint between the mountain-folded portion of the core material and the plate material is extremely strong, and the base material (the metal material of the core material and the metal material of the plate material) is resistant to both heat and chemical reaction. Material).

Therefore, according to the sandwich structure plate of this configuration, not only is the structural strength the strongest,
This has the effect of being as thermally and chemically stable as the base material. (Invention of Manufacturing Method) The method for manufacturing a sandwich structure plate of the present invention comprises a core material forming step of forming a metal flat plate into a Miura-folded core material, and a method of forming a mountain-folded portion of the core material thus formed. A joining step of resistance welding two metal plates on both sides. Then, in at least one of the core material forming step and the joining step, a synchronizing means for synchronizing between the Miura folded shape of the core material and the processing device is used.

That is, in order to mass-produce the sandwich-structured plate of the present invention, it is desirable that a core material and a plate material can be continuously produced from a continuous strip-shaped metal plate. Then, it is almost impossible to form a strip-shaped metal plate into a Miura-folded core material by a single press process, so plastic deformation such as multiple press processes or bending processes similar to press processes is performed. Processing must be done. When performing multiple plastic deformation processes, the plastic processing device is synchronized with the folds of the plate material that becomes the core material, as the fold angle of the fold made in the first plastic deformation process is gradually deepened. Must-have. Therefore, in order to continuously perform the core material forming process and enable mass production, a synchronization means for synchronizing the Miura folded shape of the core material with the processing device is required.

Further, in the joining step, two sheets are laminated on both sides of the core and the core and the sheets are resistance-welded.
In order to perform resistance welding continuously, the welding electrode must be in contact with the mountain-folded portion of the core material. Therefore, a synchronizing means for synchronizing the Miura folded shape of the core material with the processing device for performing resistance welding is required. However, there is no possibility that a manufacturing method that does not need to be synchronized in one of the core material forming process and the joining process by some means will not be developed. Was determined as a component of the manufacturing method.

The simplest and most reliable synchronization means is:
A through-hole is formed at predetermined intervals on both sides of a flat plate that is a material of a core material, and a roller having a convex portion that engages with the shape of the flat plate processed into the core material and fits into the through-hole is used as a processing device. It is to give. In such a synchronizing means, since the roller serves as a guide, it is very convenient for synchronizing with the processing apparatus. Alternatively, in addition to the synchronization means that involves contact like a roller, the positions of the mountain fold and the valley fold of the core material are measured using an optical distance measuring device, and the processing device is formed into a Miura fold shape of the core material. It is also possible to employ a synchronization means for controlling the synchronization. As described above, various types of synchronization means can be employed.

Here, the core material forming step may be a step in which the flat plate is bitten by a plurality of pairs of rollers, and the folding angle of Miura folding is gradually increased. These rollers have a three-dimensional corrugated surface corresponding to Miura folding, and the folding angle of this three-dimensional corrugated plate shape is set to be gradually deeper from the first roller pair to the last roller pair. Is desirable. In addition, it is preferable that the synchronization means for synchronizing the unevenness of the Miura-folded flat plate and the unevenness of each roller pair be used from at least the second roller pair.

According to such a core material forming step, the core material can be continuously formed from a continuous metal flat plate such as a roll plate. Has the effect of enabling mass production. Further, the joining step may be a step in which an electrode roller having a welding electrode formed at a position corresponding to the mountain-folded portion of the core material contacts the surface of the plate material to perform seam welding. is there. Here, the alignment between the mountain-folded portion of the core material and the welding electrode of the electrode roller can be performed by the above-described synchronization means.

According to such a joining step, unlike the spot welding, since the mountain fold portion of the core material and the plate material are continuously welded, stress concentration hardly occurs and an extremely strong sandwich structure plate can be formed. There is an effect that it can be manufactured. Further, since a core material having a predetermined width and continuous in the longitudinal direction can be continuously joined to two plate materials similar to each other, there is also an effect that the sandwich structure plate of the present invention can be mass-produced. .

[0019]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments of a sandwich structure plate and a method of manufacturing the same according to the present invention will be described below with reference to the accompanying drawings with reference to the drawings so as to give a person skilled in the art a practical understanding. explain. Embodiment 1 (Structure of Embodiment 1) As shown in FIG. 2, a sandwich structure plate according to Embodiment 1 of the present invention includes a core material 1 having a Miura-folded shape and mountain folds on both sides of the core material 1. And two plate members 2 respectively joined to the portion.

Here, the Miura-folded shape is, as shown in FIG. 1 again, a plane which is congruent or inverted and leaves a congruent parallelogram plane, and each side of each parallelogram is regularly mountain-folded or folded. This is a three-dimensional corrugated sheet shape obtained by valley folding. The length ratio of each side of these parallelograms and the angle formed by each side can be arbitrarily determined as a design matter.

Further, in the sandwich structure plate of the present embodiment, the core material 1 and the two plate materials 2 are each made of a rolled steel plate, and the core material 1 and the two plate materials 2 are, as shown in FIG. Each is joined by resistance welding.
That is, the seam welding is continuously performed at the welded portion W between the mountain-folded portions on both sides of the core material 1 and the inner surfaces of the two plate materials 2 that are in contact with the mountain-folded portions.

(Effects of Embodiment 1) The sandwich structure plate constructed as described above has no top surface, and almost all of the core material 1 is substantially the same as the conventional one having a zeta core as a core material. It is a parallelogram part. therefore,
Core material 1 for connecting and fixing two plate materials 2 on both sides to each other
Since the ratio of the effective portion is high and the core material 1 connects the two plate materials 2 more densely, the rigidity of the sandwich structure plate of the present embodiment is higher than that of the prior art.
In addition, since the joint is continuously seam-welded by resistance welding, the joint strength is extremely high, and the joint is not easily broken even when a large load is applied.

Therefore, according to the sandwich structure plate of the present invention, there is an effect that the rigidity is higher than that of the sandwich structure plate using the zeta core of the prior art as a core material. Also, unlike the honeycomb sandwich structure plate, the flow path is formed inside similarly to the prior art,
There is an effect that it can be used as a heat exchanger like a cooler or a radiator while having a function as a structural member. Alternatively, since the internal flow path is divided into a plurality of parts, there is an effect that two kinds of fluids can be flowed to the other side every other one, and heat exchange can be performed between the two fluids.

Furthermore, in the sandwich structure plate of this embodiment, the joint between the mountain-folded portion of the core material 1 and the plate material 2 is extremely strong, and the base material (core material 1) is resistant to both heat and chemical reaction. And the sheet material of the sheet material 2). Therefore, according to the sandwich structure plate of this configuration, there is an effect that not only the structural strength is the strongest, but also the thermal and chemical stability is almost the same as that of the base steel plate.

Therefore, if the sandwich structure plate of this embodiment is adopted as the outer plate of a portion of the hypersonic aircraft or the like where the aerodynamic heating is large, and the liquid fuel supplied to the engine is allowed to flow through the internal flow path for cooling, This is very advantageous because the outer panel has both structural strength and heat resistance. (Manufacturing Method of Embodiment 1) As shown in FIGS. 3 and 4, a method of manufacturing a sandwich-structured plate according to Embodiment 1 of the present invention is as follows. And a joining step of resistance-welding two steel plates 2 on both sides of the mountain-folded portion of the core material thus formed.
Then, in both the core material forming step and the joining step, a synchronizing means for synchronizing between the Miura folded shape of the core materials 12 to 14 and the processing device is used.

First, the core material forming step is a step in which the flat steel sheet 11 is bitten by a plurality of pairs of forming rollers 31, 31 'to 33, 33', and the folding angle of Miura folding is gradually increased. These forming rollers 31, 31 'to 33, 33'
Has a three-dimensional corrugated surface corresponding to Miura folding. And the first-stage forming roller pair 31, 31 '
The folding angle of the three-dimensional corrugated sheet shape is set to be gradually deeper from, through the second-stage forming roller pair 32, 32 'to the final-stage forming roller pair 33, 33'.

As shown in FIG. 1 again, irregularities are formed on the substantially cylindrical surface of the first pair of forming rollers 31 and 31 'in the form of a Miura fold having a very small fold angle. Are engaged with each other while leaving the thickness of the flat steel plate 11 therebetween. Then, the first-stage forming roller pair 31, 3
As shown in FIG. 3, the flat steel plate 1, which is a material of the core material 1, is sandwiched between a pair of forming rollers 31, 31 ′, and creases are formed in a mountain fold and a valley fold, thereby forming a middle portion of a shallow Miura folded shape. The material is press-formed.

On the left and right sides of the upper forming roller 31, as shown in FIGS. 3 and 4 again, a large number of punches 311 for making through holes in the left and right side edges of the intermediate material 12 are provided. It is implanted in the position corresponding to. On the other hand, a number of holes (not shown) corresponding to the respective punches 311 are formed in the lower forming roller 31 ′. Therefore, the pair of forming rollers 31 and 31 ′ of the first stage not only make the flat steel plate 11 to make the folds of the Miura fold shape, but also make the through holes in the upper and lower mountain fold portions of the intermediate material 12 formed into the shallow Miura fold shape. Form 10.

The second-stage forming roller pair 32, 32 '
As a synchronization means for synchronizing the irregularities of the intermediate material 12 subjected to the Miura folding process with the irregularities of the outer peripheral surface, a large number of projections 321 fitted into the through holes 10 formed in the mountain-folded portions of the intermediate material 12 are planted. Is embedded. That is, in the upper forming roller 32, a large number of protrusions 321 are implanted at positions corresponding to the downwardly convex mountain folds in the left and right edges of the intermediate material 12. On the other hand, a large number of protrusions 321 ′ are implanted in the lower forming roller 32 ′ at the positions corresponding to the mountain folds that are convex upwards in the left and right edges of the intermediate material 12. Note that the tips of the protrusions 321 and 321 ′
The protrusions 321 and 321 ′ are formed in a cylindrical shape so as to fit into the through-holes 10, and are formed in a hemispherical shape so as to be easily inserted into the through-holes 10 of the intermediate material 12. Further, a fitting hole in which the protrusions 321 and 321 'of each other are fitted is formed in each of the forming rollers 32 and 32' in the valley fold.

The second-stage forming roller pair 32, 32 '
Are formed on the surface of the pair of rollers so as to mesh with each other, and these concaves and convexes are formed deeper than the concaves and convexes of the first pair of forming rollers 31 and 31 '. Therefore, the second-stage forming roller pair 32, 32 '
Is formed by forming the intermediate material 12 into a Miura fold shape at a deeper fold angle by matching the unevenness of the outer peripheral surface to the position corresponding to the uneven shape of the intermediate material 12 by the projections 321 and 321 ′. I do.

Like the second-stage forming roller pair 32, 32 ', the final-stage forming roller pair 33, 33' also has a large number of projections 331, 331 'as synchronization means. On the outer peripheral surface of the final-stage forming roller pair 33, 33 ',
The irregularities of the Miura fold shape are formed further deeply, and the core material 14 is formed by forming the Miura fold shape of the intermediate material 13 to a deeper fold angle. The irregularities on the outer peripheral surface of the pair of forming rollers 33 and 33 ′ in the final stage form a Miura fold shape at a fold angle slightly deeper than the fold angle of the core material 14 in consideration of springback of the core material 14. It is formed so deep.

According to such a core material forming step, the core material 1 is continuously formed from a continuous flat steel plate 11 like a roll plate.
Since it becomes possible to mold the core material 4, it is possible to mass-produce the core material 14 having a predetermined width and continuous in the longitudinal direction. Although the forming rolls 31 to 33 'have three stages in this embodiment, if there is a need for forming the core material 14, the number of stages can be further increased and the forming can be performed gradually. Conversely, advances in roller forming technology or superplastic working technology may reduce the number of forming roller stages.

Next, as shown in FIGS. 3 and 4 again, the joining step is performed by a pair of electrode rollers 5 and 5 ′ having welding electrodes 52 formed at positions corresponding to the mountain-folded portions of the core material 14.
Abuts on the surfaces of the two plate members 2 forming the surface plate,
This is the step where seam welding is performed. Here, the core material 14
Positioning of the mountain fold portion and the welding electrode 52 of the electrode rollers 5, 5 'is performed by projections 51, 51' as synchronous means similar to the above-mentioned forming roller pairs 32, 32 'and the like.

More specifically, two flat steel plates 2 serving as surface plates are respectively contacted from both upper and lower sides of the core member 14 via a pair of guide rollers 4 so as to contact both surfaces of the core member 14. Is supplied according to the flow velocity of the liquid.
The width of the flat steel plate 2 is slightly smaller than the width of the core material 14, and the flat steel plate 2 does not cover the through holes 10 on both the left and right sides of the core material 14. The supplied flat steel sheet 2 is sent in parallel with the core material 14 in a state of contacting the ridge lines of the mountain folds on the upper and lower surfaces of the core material 14 and is sandwiched by the pair of electrode rollers 5 and 5 ′. Reach.

The pair of electrode rollers 5, 5 'is
And an intermediate portion for holding the two flat steel plates 2 while pressing them at a predetermined interval, and a right and left side having a diameter larger than that of the intermediate portion and an outer peripheral surface having a Miura-folded shape and having a large number of projections 51, 51 '. And a side end portion. The same side end sandwiches the core material 14 in which the through hole 10 is opened in the mountain folds on both the left and right sides,
Synchronizing means is formed by fitting the projections 51, 51 'into the respective through holes 10 and meshing with each other vertically. Therefore, in the same manner as the above-mentioned forming roller pair 32, 32 ', the angular positions of the electrode rollers 5, 5' with respect to the Miura folded shape of the core material 14 are accurately synchronized.

On the other hand, intermediate portions of the electrode rollers 5, 5 '
As shown in FIG. 4, a copper electrode 52 having a predetermined width and arranged in a zigzag shape around the circumference in a circumferential direction protrudes with a predetermined thickness by the number of the mountain-folded portions of the core material 14. Have been.
The electrode 52 is disposed so as to oppose the zigzag mountain-folded portion of the core material 14 with the flat steel plate 2 interposed therebetween, and one electrode is provided for the mountain-folded portion of the core material 14 connected in the longitudinal direction. 52 are provided. One electrode 52 of the upper electrode roller 5 corresponds to the closest one of the similar electrodes (not shown) of the lower electrode roller 5 ', forming a pair of electrodes. Therefore, since each electrode of the lower electrode roller 5 'corresponds to each electrode 52 of the upper electrode roller 5, a plurality of electrode pairs are formed vertically.

A high-voltage current flows between each pair of electrodes, and the voltage is appropriately controlled so that the current value is constant. That is, a voltage is adjusted to each electrode 52 of the upper electrode roller 5 so that a predetermined current flows, and similarly, a predetermined current is applied to each electrode (not shown) of the lower electrode roller 5 ′. Are adjusted so that the current flows. Further, since each electrode 52 is in contact with the surface of the flat steel plate 2 at the outer peripheral surface, the area of the contact portion between the flat steel plate 2 and each electrode 52 is extremely limited. Therefore, the electrode roller 5,
By rotating 5 ′ in synchronization with the flow of the core material 14 and the two flat steel plates 2, seam welding is performed between the upper and lower mountain folds of the core material 14 and the inner surface of the flat steel plate 2.

When the two flat steel plates 2 are seam-welded to the core member 14, respectively, two flat steel plates 2 are attached to the core member 14 by a pair of upper and lower cooling rollers 6 disposed immediately after the electrode rollers 5, 5 '. The steel plate 2 is cooled while being pressed, and the joining is completed without peeling off the seam welding. The cooling roller 6 is
A coolant is supplied to the inside through a shaft core (not shown), and is always kept at a predetermined temperature or lower. The cooling roller 6 is formed as thin as possible in a range where sufficient rigidity can be obtained.
Immediately after the electrode rollers 5, 5 ', the electrode rollers 5,
It is arranged close to 5 '. When the seam welding is completed in this manner, a sandwich structure plate including the core material 1 having a Miura-folded shape and the two plate materials 2 joined to the mountain-folded portions on both surfaces of the core material 1 is completed.

According to such a joining process, unlike the spot welding, since the mountain fold portion of the core material 1 and the plate material 2 are continuously welded, stress concentration hardly occurs and an extremely strong sandwich structure is formed. There is an effect that a board can be manufactured. As a result, as shown in FIG. 2 again, a sandwich structure plate having a Miura-folded core member 1 and two plate members (flat steel plates) 2 joined to the mountain fold portions on both sides of the core member 1 is obtained. , With a predetermined width. That is, according to the method for manufacturing a sandwich structure plate of the present embodiment, the core member 1 and the two plate members 2 continuous in the longitudinal direction having a predetermined width can be continuously joined. Therefore, it is possible to mass-produce the sandwich structure plate of this embodiment.

By combining the shape of the electrode rollers 5, 5 'and the shape of the cooling roller 6 into a barrel shape and a drum shape, respectively, it is possible to manufacture a sandwich structure plate having a gentle curved surface. It is. (Modification 1 of Example 1) In the above-described method for manufacturing a sandwich structure plate, a modification having a joining step of separately performing upper seam welding and lower seam welding is also possible.

That is, as shown in FIG. 5, it is also possible to perform seam welding only on the upper side with the electrode rollers 7, 7 'and perform seam welding only on the lower side with the electrode rollers 8, 8'. Here, the upper electrode roller 7 of the first stage has a plurality of electrodes similarly to the above-mentioned electrode roller 5, while the lower electrode roller 7 'of the first stage has a single electrode made of copper having a uniform outer peripheral surface. It is a roller made of. Therefore, if a predetermined current is applied to each electrode of the upper electrode roller 7 and seam welding is performed, and the lower electrode roller 7 'collects a wide current, only the upper side is seam welded. You.

Conversely, the upper electrode roller 8 in the second stage is a roller made of a single electrode made of copper with a uniform outer peripheral surface, while the lower electrode roller 8 'in the second stage is Like the electrode roller 5, it has a plurality of electrodes. Therefore, if a predetermined current is applied to each electrode of the lower electrode roller 8 ′ to perform the seam welding, and the current is widely collected by the upper electrode roller 8, only the lower side is seam welded. Is done.

According to this modification, since the upper seam welding and the lower seam welding are performed separately, the voltage control of each electrode of the electrode roller 7 and each electrode of the electrode roller 8 'becomes easy. This has the effect. (Modification 2 of Embodiment 1) In the above-mentioned method for manufacturing a sandwich structure plate, an optical measuring means is arranged between the forming rollers of each stage, and the Miura folded shape of the intermediate materials 12 and 13 is optically observed. In addition, it is also possible to implement a modification in which synchronization is achieved between the forming rollers of each stage. Further, it is also possible to eliminate the through-hole and use the Miura folded shape itself as a synchronization means with the forming rollers of each stage. As a means for adjusting the feed speed between the forming rollers in each stage, a means for adjusting the feed speed between the rolling rollers in each stage can be diverted in the production process of the rolled steel sheet. .

Embodiment 2 (Structure of Embodiment 2) A sandwich structure plate according to Embodiment 2 of the present invention includes a core member made of a synthetic resin having a Miura-folded shape and a mountain on both sides of the core member. It is composed of two aluminum alloy plates joined to the folded portion by an adhesive.

(Manufacturing Method of Embodiment 2) The core material may be formed by press-molding a flat plate made of a thermoplastic resin, or may be formed by injection-molding a suitable synthetic resin. A thermosetting resin-based adhesive turned into a clay at a low temperature is applied in the form of a thin tape to the ridge lines of the mountain folds on both sides of the core material, and is continuously bonded to the plate material. At the time of bonding, first, the lower mountain-folded portion of the core material is bonded to the lower plate material, and then the upper plate is turned upside down and the second plate material is bonded similarly. By doing so, the adhesive covers the ridge line of the mountain-folded portion of the core material with surface tension, so that stronger bonding can be obtained.

(Effects of Embodiment 2) The sandwich structure plate of this embodiment can be used as a structural material almost equivalent to a honeycomb sandwich structure plate because it has a considerable rigidity while being lightweight. In addition, there is an effect that the rigidity is superior to that of the sandwich plate having the zeta core according to the related art. In addition, since the internal flow path is formed differently from the honeycomb sandwich structure plate, there is also an effect that a fluid such as cooling air can be used while being cooled while flowing.

It should be noted that a curvature may be given when molding the core material,
Alternatively, it is possible to produce a sandwich plate having a desired curvature by giving a curvature at the time of joining the core material and the two plate materials.

[Brief description of the drawings]

FIG. 1 is a development view showing an example of an arrangement of folds of a Miura fold

FIG. 2 is a cross-sectional view illustrating a configuration of a sandwich structure plate as Example 1.

FIG. 3 is a side view showing the manufacturing method according to the first embodiment.

FIG. 4 is a plan view showing a manufacturing method according to the first embodiment.

FIG. 5 is a side view showing a manufacturing method as a first modification of the first embodiment;

[Explanation of symbols]

1: core material (made of steel plate) 2: plate material (made of steel plate) 3: welded portion (seam welding) 10: through hole 11: steel plate (material of core material) 12, 13: intermediate material 14: core material 31, 31 ′ , 32, 32 ', 33, 33': forming roller 311: punch 321, 321 ', 331, 331': projection (synchronizing means) 4: guide roller 6: cooling roller 5, 5 ', 7, 7', 8, 8 ': Electrode roller 51, 51': Projection (synchronization means) 52: Seam welding electrode

Claims (5)

[Claims] 1. A sandwich structure plate comprising: a core member having a Miura-folded shape; and two plate members respectively joined to mountain fold portions on both sides of the core member. 2. The sandwich structure plate according to claim 1, wherein said core member and said plate members are each made of a metal material, and said core member and said plate members are respectively joined by resistance welding. 3. A core material forming step of forming a metal flat plate into a Miura-folded core material, and a joining step of resistance-welding two metal plate materials to both sides of the mountain-folded portion of the core material. Wherein at least one of the core material forming step and the joining step uses a synchronizing means for synchronizing between the Miura folded shape of the core material and a processing device, wherein the sandwich structure plate is provided. Manufacturing method. 4. The core material forming step is a step in which the flat plate is bitten by a plurality of pairs of rollers, and the folding angle of Miura folding is gradually increased. The three-dimensional corrugated sheet has a corrugated surface, and the folding angle of the three-dimensional corrugated sheet is gradually set deeper from the first roller pair to the last roller pair. The method for manufacturing a sandwich structure plate according to claim 3, wherein the synchronization means for synchronizing the processed unevenness of the flat plate with the unevenness of each roller pair is used. 5. The joining step is a step of performing seam welding by contacting an electrode roller having a welding electrode formed at a position corresponding to the mountain-folded portion of the core material with a surface of the plate material, 4. The method for manufacturing a sandwich structure plate according to claim 3, wherein the positioning between the mountain-folded portion of the core material and the welding electrode of the electrode roller is performed by the synchronization means.