JP2000289131A - Honeycomb panel and production thereof - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a lightweight honeycomb panel consisting of a honeycomb core and face sheets bonded in sufficient bonding strength and having no excessive thermal strain in its bonded part. SOLUTION: A honeycomb core 1 with 1 mm or less thick plate a corrugate shape wherein projected and recessed trapezoidal parts are continued alternately is used. A face sheet 2 on a projected side and the top surfaces of the projected parts of the honeycomb core are bonded by a plurality of discontinuous spot bonding rows due to laser beam and a face sheet 3 on a recessed side and the bottom surfaces of the recessed parts of the honeycomb core 1 are also bonded by a plurality of discontinuous spot bonding rows by laser beam. If necessary, a honeycomb panel having no welding mark on the outer surface of either one of the face sheets thereof, a honeycomb panel having an edge material arranged to at least one side surface thereof or a honeycomb panel having a curved surface shape can be produced.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a honeycomb panel which can be used as a lightweight structural member such as a small boat such as a vehicle and a motor boat, an aircraft, a lightweight building, furniture, a transportation pallet and the like, and a method of manufacturing the same.

[0002]

2. Description of the Related Art A honeycomb panel in which a corrugated metal honeycomb core (corrugated metal reinforcing material) is sandwiched between two metal plates,
Since it is lightweight but has excellent rigidity, it is widely used as a structural member for vehicles, small boats, aircraft, lightweight buildings, and the like.

Although the thickness of the corrugated metal reinforcement is 2 to 10 mm and the thickness of the metal plate sandwiching the reinforcement is 5 to 15 mm, the honeycomb panel is different from the honeycomb panel of the present invention. No. 92143 discloses that two corrugated metal reinforcing members are fixed on both sides thereof by a continuous seam welding welding line extending between the corrugated metal reinforcing members and the corrugated convex portions and concave portions. A composite panel formed by parallel plates is described. It also describes that a welding line by continuous seam welding is formed using a high-power CO ₂ laser.

During welding, the metal in the weld is melted, solidified, and cooled. In this process, the metal structure and the shape of the metal in the weld change, so that the metal in the weld expands or contracts. As a result, thermal stress and thermal strain are generated between the metal other than the welded portion. When welding with this thermal stress or thermal strain is continuously performed to form a weld line, the generated thermal stress or thermal strain is accumulated along the weld line and becomes large thermal stress or thermal strain.

[0005] In vehicles, small boats, aircraft, and lightweight structures, a honeycomb panel using a thin corrugated sheet having a thickness of less than 1 mm is usually used. According to the knowledge of the present inventors, since a thick corrugated sheet has rigidity, distortion is small even when a long welding line is formed. However, when a long welding line is formed on a thin corrugated sheet having a thickness of less than 1 mm, a large number of wrinkled strain defects are generated on the corrugated sheet along the welding line. When the output of the laser beam is adjusted and changed, the wrinkle-like flaw is reduced, but the adjustment and change are extremely troublesome.

Instead of forming a long welding line, a method of forming a large number of discontinuous point joints along one joining line and joining the honeycomb core and the metal plate can be considered. If this method is performed by increasing the interval between point junctions, the thermal stress and thermal strain generated at one point junction and the thermal stress and thermal strain generated at the adjacent point junction do not accumulate with each other. Therefore, it is possible to reduce the occurrence of a large thermal stress or thermal strain along one joint line, and to prevent the occurrence of wrinkles.

However, if the distance between the point joints is large, the number of the point joints formed along the joining line is reduced, and the joint strength between the corrugated sheet and the face sheet becomes insufficient.
It is conceivable to perform the point joining densely by reducing the interval between the point joining and the point joining.However, if the point joining formed densely along the joining line is performed, it approaches the case where a continuous welding line is formed, Thermal stress and thermal strain are accumulated along the joining line, and wrinkles are likely to occur.

[0008]

The present invention relates to a honeycomb panel using a honeycomb core of a corrugated sheet having a thickness of 1 mm or less, wherein the honeycomb core and the face sheet are joined with sufficient joining strength, and It is an object of the present invention to provide a honeycomb panel having no thermal strain or wrinkle-like flaws at a joint of a face sheet and a method of manufacturing the same.

[0009]

FIG. 1 is a perspective explanatory view of an example of a honeycomb panel according to the present invention. That is, the present invention provides (1)
A honeycomb having a honeycomb core 1 of a corrugated sheet having a shape in which a trapezoid having a convex cross section and a trapezoid having a concave cross section are alternately continuous and having a plate thickness of 1 mm or less, and two face sheets 2 and 3 sandwiching the corrugated sheet 1 In the panel, the face sheet 2 on the convex top surface side and the respective convex top surfaces, for example, 4-1 of the honeycomb core 1 are connected by a laser beam to discontinuous point joining of a plurality of rows in the longitudinal direction of the convex top surface. Face sheet 3 joined to each other by rows 6 and 7 such as 4-1-1 and 4-1-2 and having a concave bottom side
And each concave bottom surface of the honeycomb core 1, for example, 5-4
Means a plurality of rows of discontinuous point junctions in the longitudinal direction of the concave bottom surface by a laser beam, for example, 5-4-1, 5-1-4-2.
A honeycomb panel characterized by being joined to each other by a honeycomb panel. Note that the trapezoid may be a quadrangle in which the oblique side and the top side or the bottom side are at right angles.

It is desirable that the honeycomb panel used for a vehicle, a small boat, an aircraft, or a lightweight building has both characteristics of lightness and rigidity. A corrugated plate is a flat plate having a large area when converted to a flat plate. Therefore, a honeycomb panel using a thick corrugated sheet having a plate thickness of more than 1 mm has a large weight, which impairs lightness. In order to secure lightness, the thickness of the honeycomb core is preferably 1 mm or less, more preferably 0.3 to 0.5 mm.

In the honeycomb panel, if the honeycomb core moves during use and the honeycomb core becomes dense and rough, the rigidity of the rough portion is impaired and the rigidity becomes uneven. For this reason, in the present invention, the convex top surface 4 (4-
Are joined to the face sheet 2, and the concave bottom surfaces 5 (5-1, 5-2, ...) of the honeycomb core are joined to the face sheet 3.

In joining thin metal plates having a thickness of 0.3 to 0.5 mm, it is extremely important to control the amount of heat input. When welding, a thin metal plate with a thickness of 0.3 to 0.5 mm melts,
The molten metal plate does not become a layered molten metal having a thickness of 0.3 to 0.5 mm, but tends to become a sphere having a diameter exceeding 1 mm due to the surface tension of the molten metal. In ordinary electric resistance welding or arc welding, a thin metal plate of 0.3 to 0.5 mm melts into a spherical shape having a small joining force and a diameter exceeding 1 mm. For this reason, joining is difficult by electric resistance welding or arc welding. Laser beams, especially pulsed laser beams, make it easy to accurately control the amount of heat input.Thus, even with a thin honeycomb core with a thickness of 0.3 to 0.5 mm, the molten metal does not become spherical,
Welds easily to facesheets.

As a method of joining the top surface 4-1 of the honeycomb core 1 to the face sheet 2, it is conceivable to form one continuous welding line along the joining line 4-1-1. However, when a continuous welding line is formed, the joining line 4-1-1 is formed.
A large thermal strain is generated along the sheet, and the sheet thickness is 0.3-0.
・ In the case of a honeycomb core having a thickness of 5 mm, many wrinkle-like distortion defects occur.

Instead of forming a long welding line, a large number of discontinuous point joints are formed along one joining line 4-1-1, and the top surface 4-1 of the honeycomb core and the face sheet are formed. 2
Can be considered. At this time, the point junctions 6 and 6 '
Is small and the points are densely joined, wrinkles are generated along the joining line 4-1-1 as in the case where a continuous welding line is formed. When the point joints 6 and 6 'are large and the point joints are coarsely joined, the thermal stress and thermal strain generated in one point joint 6 do not accumulate in 6', preventing the occurrence of wrinkles. You can do it. However, if the distance between the point joints 6 and 6 'is large, the number of point joints formed along the joining line 4-1-1 decreases, and the joining strength between the top surface 4-1 of the honeycomb core and the face sheet 2 is reduced. Becomes insufficient.

Although not described in the prior art, in the present invention, a plurality of rows of discontinuous point junctions are formed, for example, as 4-1-1 and 4-1-2, so that the top of the honeycomb core is formed. Face 4
-1 is joined to the face sheet 2. In the present invention, since the distance between the point joints 6 and 6 'along the joining line 4-1-1 is sufficiently large, thermal strain does not accumulate along the joining line 4-1-1, and therefore, wrinkles are not generated. No flaws occur. In the present invention, the number of junctions along the joining line 4-1-1 is small because the interval between 6 and 6 'is sufficiently large, but also along the joining line 4-1-2, such as 7,7'. Are point-joined. For this reason, many point joints are formed on the joint surface between the top surface 4-1 of the honeycomb core and the face sheet 2. Accordingly, the bonding strength between the top surface 4-1 of the honeycomb core and the face sheet 2 is sufficiently large.

According to the present invention, (2) a plurality of rows of discontinuous point joints in the longitudinal direction of the convex top surface may be formed of a plurality of rows of discontinuous point joints by laser beam irradiation from the honeycomb core side. A row or a plurality of rows of discontinuous spot welding in the longitudinal direction of the concave bottom surface are a plurality of rows of discontinuous spot welding by laser beam irradiation from the honeycomb core side; The honeycomb panel according to (1), wherein there is no welding mark on the outer surface of any one of the face sheets.

FIG. 2 is an explanatory view of a honeycomb panel having no welding mark on the outer surface of one of the face sheets.
(A) is an explanatory view of a first step of bonding, and (B) is an explanatory view of a second step of bonding. In FIG. 2A, the honeycomb core 1
Are arranged, for example, on the face sheet 3, and have a concave bottom surface, for example, a plurality of discontinuous spot welding rows 6-2 in the longitudinal direction.
1 and 7-1 are laser beams 8 from the honeycomb core side,
8 ′, welding marks of 6-1 and 7-1 are formed on the face sheet 3
It is formed so as not to reach one outer surface 3-1. Next, FIG.
As shown in (b), the face sheet 2 is disposed on the honeycomb core 1 and the spot welding rows 6-2 and 7-2 are arranged on the face sheet 2.
It is formed by laser beams 8, 8 'from the side. The honeycomb panel formed by the method of FIG. 2 is beautiful without welding marks on the outer surface 3-1 of one face sheet 3.

According to the present invention, (3) an edge member for attaching the honeycomb panel to another member is provided on at least one side surface of the honeycomb panel, and is joined to each of the two face sheets. The honeycomb panel according to the above (1) or (2), wherein: According to the present invention, (5) both of the two face sheets and the edge material are joined by a laser beam in a plurality of discontinuous point joining rows in the length direction of the edge material. The honeycomb panel according to (3), wherein (6) a gap between discontinuous point joints between the edge material and the face sheet is smaller than a gap between discontinuous point joints between the face sheet and the core. The honeycomb panel according to the above (5), wherein

The honeycomb panel is attached to another member, for example, another honeycomb panel to form a large area honeycomb panel.
Alternatively, it is used by being attached to another member such as a column.
In this case, it is preferable that at least one side surface of the honeycomb panel is provided with an edge material for attaching to another member. FIGS. 3A and 3B show examples of the edge material 9 joined to each of the two face sheets and arranged. FIG. 3A shows an example of the face sheet 3 and the edge material 9, and FIG. And FIG. 3 is a diagram showing an example of joining of the edge material 9 with the edge material 3.
In the figures, reference numerals 10 and 10 'denote welding joints by a laser beam. When a shear load or a bending load is applied to the panel, a large reaction force is generated at the joint 10 ′ between the edge member 9 and the face sheets 2, 3. It is characterized in that it is made denser than the interval between a few point junctions 10. On the other hand, by making the interval between the point joint 10 between the core 1 and the face sheets 2 and 3 coarser than the point joint 10 ′ between the edge material 9 and the face sheets 2 and 3,
The number of welding points can be reduced and efficiency is improved.

The present invention also provides (4) a honeycomb core having a curved corrugated plate, two face sheets sandwiching the corrugated corrugated plate, and two curved sheets conforming to the curved corrugated plate. (1) to (3), which are face sheets.
It is a honeycomb panel as described in any one of the above. FIG. 4 shows an example of this curved honeycomb panel, wherein 1 'is a honeycomb core of a curved corrugated sheet, 2' and 3 'sandwich a curved corrugated sheet 1'.
It is an example of two face sheets having a curved surface shape along the curved surface shape of a corrugated sheet.

According to the present invention, (7) one laser beam is divided into a plurality of laser beams by passing through a laser beam splitter, and the divided plurality of laser beams are divided into one convex peak of a honeycomb core. By irradiating by moving in the length direction of the surface or in the length direction of one concave bottom surface of the honeycomb core, a plurality of discontinuous point bonding rows in the length direction of the convex top surface are formed. The method of manufacturing a honeycomb panel according to any one of (1) to (6), wherein a plurality of discontinuous point-joining rows in the length direction of the bottom surface are formed.

As described with reference to 5-4-1 and 5-4-2 in FIG. 1, in the honeycomb panel of the present invention, the face sheet on the concave bottom surface side and each concave bottom surface of the honeycomb core are concave by the laser beam. Of rows of multiple point junctions in the longitudinal direction of the bottom surface
And 5-4-2. The plurality of rows of point junctions 5-4-1 and 5-4-2 can be formed using two separate laser beams obtained from two separate laser beam oscillators. A single laser beam obtained from the laser beam oscillator described above is divided into a plurality of laser beams, and 5-4-1 and 5-4-2 are formed using each of the plurality of divided laser beams. You can do things.

FIG. 5 is an explanatory view showing an example in which a laser beam is divided into two by a chevron lens. That is, when one laser beam 11 obtained from an optical fiber is passed through a laser beam splitter composed of, for example, a magnifying lens, a chevron lens, and a condenser lens, two laser beams 11
-1 and 11-2. When these two laser beams 11-1 and 11-2 are moved at right angles to the plane of the paper and the concave bottom surface of the honeycomb core 1 is irradiated with the laser beams, a row of two point joints 5-4 in one movement is obtained. -1 and 5-4-2 can be formed simultaneously, and the efficiency is high. Row 5 of the point junction
Since the distance L between -4-1 and 5-4-2 is always kept the same, two rows of point joints having high dimensional accuracy can be obtained.
In this method, since one laser beam oscillator is used, the honeycomb panel manufacturing apparatus is inexpensive and simple.

[0024]

BEST MODE FOR CARRYING OUT THE INVENTION
Using a SUS304 thin plate having a thickness of 0.4 mm, a honeycomb core of a corrugated sheet in which a trapezoid having a convex cross section and a trapezoid having a concave cross section were alternately continued was prepared. The dimensions of the corrugated sheet are the convex top surface 4-
1,4-2, ... each width is 12.5mm, concave bottom 5
Each width of -1, 5-2, ... is also 12.5mm,
The pitch of 4-1 and 4-2 is 50mm, 5-1 and 5-
The pitch of 2,... Is also 50 mm, and the difference between the heights of 4-1 and 5-1 (wave height) is 40 mm. The face sheet 2 shown in FIG. 1 has a thickness of 0.6 mm.
Is a JIS SUS304 steel plate having a thickness of 1.0 mm. Each of the honeycomb core 1, the face sheets 2 and 3 has a width of 1000 mm and a length of 1000 mm.

The present inventors have proposed a YA having an oscillation output of 400 W.
Focal length 50 by pulse oscillation using G laser oscillator
The honeycomb core 1 and the face sheets 2 and 3 were joined to each other by a method shown in FIG. Rows 4-1-11 and 4 of the two point junctions in FIG.
The distance between -1-2 is 9 mm, and the distance between the discontinuous point joints 6 and 6 'and the distance between 7 and 7' are 5 mm, respectively. FIG.
Similarly, the interval between the rows 5-4-1 and 5-4-2 of the point junction of FIG.
mm, the spacing of the non-continuous point joints of 5-4-1 and 5
The interval between the non-continuous spot junctions -4-2 is also 5 mm. Note that a row of two point junctions, for example, 4-1-1 and 4-1
-2 is the two divided laser beams 1 shown in FIG.
It was formed simultaneously using 1-1 and 11-2.

The honeycomb panel of the comparative example uses a honeycomb core and a face sheet of the same dimensions and the same steel type as those used in the above-described honeycomb panel of the present invention, but the honeycomb core and the face sheet are joined in two points. A row of point junctions was formed without forming a row of junctions. That is, one row of discontinuous point joints with a 9 mm spacing between the point joints is formed at the top of the convex surface, for example, at the center of 4-1. Formed one row of 9 mm discontinuous point joints.

When a continuous welding line is formed on a thin honeycomb core having a thickness of 0.4 mm and joined to the face sheet, a large number of wrinkle-like flaws are generated along the welding line, making joining difficult. However, since the honeycomb panel of the present invention and the honeycomb panel of the comparative example were joined by discontinuous point joining rows, no wrinkle-like flaw was generated, and the joining was able to be performed smoothly.

The present inventors sampled a sample having a width of 230 mm and a length of 50 mm from the honeycomb panel of the present invention and the honeycomb panel of the comparative example, and subjected to a bending test. FIG. 6A is an explanatory view of the bending test method, and FIG. 6B is the result of the bending test. As can be seen from FIG. 6 (b), the honeycomb panel of the comparative example has a large displacement at a load of 200 kg and cannot withstand a larger load, but the honeycomb panel of the present invention has a small displacement even at a load of 300 kg. Can be used enough.

The present inventors estimated that the honeycomb panel of the present invention and the honeycomb panel of the comparative example had a width of 100 mm and a length of 100 mm.
Was sampled and subjected to a tensile test. FIG. 7A is an explanatory view of a tensile test method, in which a face sheet of a honeycomb panel is bonded to a tensile jig using a strong adhesive, and a tensile test is performed. FIG. 7B shows the result of the tensile test.
As shown in FIG. 7 (b), in the comparative example, the displacement becomes large with a tensile load of about 500 kg, and the honeycomb panel of the present invention cannot withstand a tensile load of more than 1000 kg.
Even with a tensile load of kg, the displacement is small and it can be used satisfactorily.

The present inventors have found that the honeycomb panel of the present invention and the honeycomb panel of the comparative example have a width of 100 mm and a length of 100 mm.
Was sampled and subjected to a shear test. FIG. 8A is an explanatory view of a shear test method, in which a face sheet of a honeycomb panel is bonded to a shearing jig using a strong adhesive, and a shear test is performed. FIG. 8B shows the result. As can be seen from FIG. 8 (b), in the comparative example, the displacement increases with a shear load of about 500 kg, and the shear force cannot withstand a greater shear load.
The honeycomb panel of the present invention was sufficiently usable even with a shear load of 1000 kg.

The present inventors joined the edge material around the honeycomb panel of the present invention with a laser beam. On this occasion,
The gap between the discontinuous point joining of the edge material and the face sheet is 2mm,
The interval between the two rows of the point joining was 9 mm. On the other hand, as a comparative example of the shear strength, one having the same point-joining interval as the point-joining interval of 5 mm between the face sheet and the core was separately manufactured. These were subjected to a shear test using a shear test jig as shown in FIG. As a result, as shown in FIG. 9 (b), in the comparative example, peeling occurred at the joint between the edge material and the face sheet under a load of about 2 ton, and it was broken at about 2.5 ton. Twice the strength was obtained.

[0032]

The honeycomb panel of the present invention has a thickness of 1 mm.
Since the following honeycomb core of a thin corrugated sheet is used, it is lightweight. Moreover, since the honeycomb core and the face sheet are joined with sufficient joining strength, they have excellent rigidity. Moreover, the honeycomb core and the face sheet can be easily joined without causing excessive thermal strain at the joint between the honeycomb core and the face sheet and without generating wrinkle-like flaws.

[Brief description of the drawings]

FIG. 1 is a perspective explanatory view of an example of a honeycomb panel of the present invention.

FIG. 2 is an explanatory view of a honeycomb panel having no welding mark on the outer surface of any one of the face sheets.

FIG. 3 is an explanatory view of a honeycomb panel in which a rim is arranged on at least one side surface.

FIG. 4 is an explanatory view of a honeycomb panel having a curved surface.

FIG. 5 is an explanatory diagram of an example of a laser beam splitter used in the present invention.

FIG. 6 is an explanatory view of a bending test of a honeycomb panel.

FIG. 7 is an explanatory diagram of a tensile test of a honeycomb panel.

FIG. 8 is an explanatory diagram of a shear test of a honeycomb panel.

FIG. 9 is an explanatory diagram of a shear test of a honeycomb panel to which edge materials are joined.

[Explanation of symbols]

1 (1 ') Honeycomb core 2 (2') Face sheet 3 (3 ') Face sheet 4-1 (4-2, 4-3) Convex top surface of honeycomb core 4-1-1 (4-1- 2,4-2-1, 4-2-2)
Rows of discontinuous point joints 5-1 (5-2, 5-3, 5-4) Recessed bottom surface of honeycomb core 5-4-1 (5-4-2) Rows of discontinuous point joints 6 ( 6 ') Point joining 7 (7') Point joining 8 (8 ') Laser beam 9 Edge material 10 (10') Point joining 11 Laser beam before division 11-1 (11-2) Divided laser beam.

 ──────────────────────────────────────────────────続 き Continuing from the front page (72) Inventor Mitsunori Abe 3434 Shimada, Hikari-shi, Yamaguchi Prefecture Nippon Steel Corporation Hikari Works (72) Inventor Moto Kido 20-1 Shintomi, Futtsu City, Chiba Prefecture Made in New Japan No. Suzuki, Inventor 20-1 Shintomi, Futtsu-shi, Chiba Nippon Steel Corporation R & D Headquarters (72) Inventor Yuichi Yoshida 20-1, Shintomi, Futtsu-shi, Chiba F-term (Reference) in Technology Development Division, Steel Corporation 4E068 BF01 CD04 CE02 DA00 4F100 AB01 AB04 AT00B AT00C BA03 BA06 BA10B BA10C BA13 DC02A EC172 EJ522 GB31 GB81 JK01 JL00 JL03

Claims (7)

[Claims] 1. A quadrangle or trapezoid whose cross section is convex,
A convex top surface of a honeycomb panel having a corrugated honeycomb core having a thickness of 1 mm or less and having intermittent or continuous concave quadrangular or trapezoidal shapes and two face sheets sandwiching the corrugated plate. Side face sheet and the respective convex top surfaces of the honeycomb core are joined to each other by a plurality of discontinuous point joining rows in the longitudinal direction of the convex top face by a laser beam, and the concave bottom side. Wherein the face sheet and the concave bottom surface of the honeycomb core are joined to each other by a plurality of discontinuous point-joining rows in the longitudinal direction of the concave bottom face by a laser beam. panel. 2. A plurality of discontinuous point-joining rows in the length direction of the convex top surface are a plurality of discontinuous point-joining rows by laser beam irradiation from the honeycomb core side, or concave. Is a plurality of rows of discontinuous point bonding in the longitudinal direction of the bottom surface of the plurality of rows of discontinuous point bonding by irradiation of a laser beam from the honeycomb core side, and is one of two face sheets. The honeycomb panel according to claim 1, wherein there is no welding mark on an outer surface of the face sheet. 3. An edge material for attaching the honeycomb panel to another member is provided on at least one side surface of the honeycomb panel so as to be joined to each of the two face sheets. The honeycomb panel according to claim 1 or 2. 4. The honeycomb core according to claim 1, wherein the honeycomb core is a curved corrugated sheet, and the two face sheets are two face sheets having a curved surface conforming to a curved corrugated sheet sandwiching the curved corrugated sheet. The honeycomb panel according to any one of claims 1 to 3, wherein 5. The method according to claim 1, wherein each of the two face sheets and the edge material are joined by a laser beam in a plurality of discontinuous point joining rows in the length direction of the edge material. Item 4. The honeycomb panel according to Item 3. 6. The honeycomb according to claim 5, wherein a gap between discontinuous point joints between the edge material and the face sheet is made smaller than a gap between discontinuous point joints between the face sheet and the core. panel. 7. A laser beam is split into a plurality of laser beams by passing through a laser beam splitter.
By moving a plurality of divided laser beams in the length direction of one convex top surface of the honeycomb core or in the length direction of one concave bottom surface of the honeycomb core, and irradiating the divided laser beams, the convex top surface is formed. 7. A method according to claim 1, wherein a plurality of rows of discontinuous point joints in the longitudinal direction or a plurality of discontinuous point joint rows in the longitudinal direction of the concave bottom face are formed. A method for manufacturing a honeycomb panel according to any one of the above.