JPH0761693B2 - Method for forming honeycomb core for curved surface formation - Google Patents

Description

The present invention relates to a method for forming a curved surface forming honeycomb core.

More specifically, the present invention relates to a method of forming a high-quality honeycomb core for forming a curved surface, which is suitable for forming a complicated curved surface such as a cubic curved surface.

"Prior art" and "Problems to be solved by the invention" Generally, since the honeycomb core has features such as easy molding and the maximum weight specific strength, a substantially regular hexagon formed by the expansion forming means. The thing which consists of the planar aggregate | assembly of the shape of a hollow columnar cell is often used. However, when forming a curved honeycomb core with such a honeycomb core, for example, when the honeycomb core is curved in the expansion direction (or ribbon direction) along the curved surface, a direction orthogonal to the expansion direction (or ribbon direction) of the honeycomb core, That is, the ribbon direction (or expansion direction) is warped upward in the opposite direction, distorted into a saddle shape, without fitting to a curved surface type, if you try to fit it by applying an excessive force, the cell wall will be broken, Moreover, since a peeling or the like occurs at the bonded portion, it is not possible to form a highly accurate curved honeycomb core.

Therefore, it can be easily processed into a curved surface, and
As a honeycomb core capable of forming a high-quality curved honeycomb core, for example, as shown in FIG. 7, a honeycomb core formed of a planar assembly of cells having a substantially regular hexagonal shape is further provided in the spreading direction. A honeycomb core suitable for forming a curved honeycomb core formed by expanding a predetermined amount, that is, a bending angle of the cell walls 22 and 23 constituting each cell 21, 21 ... Rectangular cell 21,
A so-called over-expanding core 20 composed of a planar assembly of 21 ... Alternatively, as shown in FIG. 8, the honeycomb core constituent materials 31, 31 ... Which are formed in a predetermined corrugated shape are sequentially replaced with the respective concave portions 32, 32 ... Of the adjacent honeycomb core constituent materials 31, 31. The protrusions 33, 33 ... Are arranged in such a positional relationship that they abut, and the contact portions between these recesses 32, 32 ... And the protrusions 33, 33. There is provided a so-called flexible core 30 or the like formed by stacking the honeycomb core constituent materials 31, 31, ...

However, in the former case, the cell walls 23, 23 ...
Since the cell walls 22, 22, which are continuously located in a straight line along the ribbon direction L and are located along the ribbon direction L are alternately displaced by half a pitch in the spreading direction W, for example,
When curved along the curved surface type in the ribbon direction L, the spacing between the cell walls in each of the cells 21, 21 ... Does not change in the spreading direction W on either the concave curved surface or the convex curved surface. In L, the concave curved surface side contracts and the convex curved surface side expands. However, this change in the spacing in the ribbon direction L is caused by the cell walls 2 positioned orthogonal to the ribbon direction L.
3, 23 ... Twist and deform, and the resulting deformation is mostly absorbed by the elastic deformation of the material.
, 23, 23, and the like, and the characteristics that the fitting to the curved surface type is easily performed without causing a phenomenon such as peeling or the like at the joint portion and warping of the expanding direction W. However, on the other hand, when bending in the spreading direction W,
Since the cell walls 23, 23 ... Are located in a straight line in the spreading direction W, and the state thereof exists as a single plate, the bending rigidity is large in order to bend in this direction. It is extremely difficult to form a curved honeycomb core curved in the direction W. Therefore, the over-expanded core 20 cannot form a honeycomb core having a complicated curved surface such as a high-quality cubic curved surface.

In addition, the latter is extremely flexible and can easily form a complicated curved honeycomb core such as a cubic curved surface, but the honeycomb core constituent materials 31, 31 ... Since the molding is performed by such a method, there is a drawback that the molding is extremely troublesome and the honeycomb core 30 becomes expensive.

Therefore, as shown in FIG. 4, the planar shape of each of the cells 12, 12 ... Has a substantially drum shape, and each of the cells 12, 12 ...
The cell walls 13, 13 located along the ribbon direction L of the cells 21, 21 adjacent to each other in the spreading direction W are bonded to each other by an adhesive 16 or the like in a corresponding positional relationship. A straight line that is arranged in a straight line along W, and that is located adjacent to each of the cells 12, 12 ... Which are arranged in a straight line in the direction orthogonal to the spreading direction W (ribbon direction L). Each of the cells 12, 12 ...
There is provided a curved surface-forming honeycomb core 11 suitable for forming a curved honeycomb core arranged so as to be alternately displaced by half a pitch in the spreading direction W.

In this curved surface forming honeycomb core 11, for example, as shown in FIG. 5 and FIG. 6, when it is bent along the curved surface mold 17 in the expanding direction W in order to form a curved honeycomb core 11a. , The distance between the cell walls 13 located along the ribbon direction L in each cell 12, 12 changes so as to shrink on the concave curved surface side and expand on the convex curved surface side.
Cell walls 1 located along the ribbon direction L in 2, 12 ...
The change in the interval between 3 and 13 is that the cell walls 14 and 14 located in the zigzag shape along the spreading direction W, especially the cells 12 and 12 ...
In the constricted parts 15, 15, ...
Side) contracts and each cell wall 14, 14 ... twists and deforms so as to expand on the convex curved side (14b side), and this twisting deformation is mostly absorbed by the deformation of the material forming the cell walls 14, 14 ... Therefore, the cell walls 14, 14 ... Are not broken, and the bonded portions of the cell walls 13, 13 ... Are not peeled off, and the curved surface mold 17 is easily fitted. Therefore, it is possible to form a high-quality curved honeycomb core 11a having a large curvature also in the extending direction W.

Further, when curved in the extending direction W, in the constricted portions 15, 15 of each of the cells 12, 12, the intervals between the cell walls 14, 14 contract on the concave curved surface side (14a side), and the convex curved surface side (14a side) contracts. Since the cell walls 14 are deformed so as to expand on the side (14b), the curved honeycomb core 11a curved in the expansion direction W naturally curves in the ribbon direction L in the same direction as the expansion direction W by a predetermined amount. It transforms to do. Therefore, the curved honeycomb core 11a having a complicated curved surface such as a high-quality cubic curved surface can be easily formed.

However, in the conventional method for forming the honeycomb core 11 for forming a curved surface, the over-expanded core 20 is formed in the expansion direction W.
Since one side portion is supported in a fixed state and a predetermined load is uniformly and gradually applied from the other side portion side of the spreading direction W in the ribbon direction L, the forming is troublesome and particularly , Over-expanded core before molding
When the thickness of 20 is extremely thin or its size is large, etc., the honeycomb core for forming a curved surface with a uniform cell shape
Molding 11 was extremely difficult.

The present invention has been made in view of the above circumstances, and an object thereof is not limited by the thickness, size, etc. of the overexpanded core before molding, and can be easily performed from an overexpanded core of any configuration. Another object of the present invention is to propose a method for forming a surface-forming honeycomb core, which is capable of forming a high-quality curved-surface forming honeycomb core.

"Means for Solving Problems" The present invention has been made to achieve the above object, and a technical solution thereof is a flat surface of a hollow columnar cell having a flat substantially hexagonal shape formed by a stretch forming means. A honeycomb core made of a static aggregate is further expanded in the expanding direction, and an overexpanded core in which each cell has a substantially rectangular shape is formed in a pair of suction holes communicating with a suction device. Between the panels, it is held in an airtight manner by a plate-shaped sliding member that penetrates through a large number of through holes to communicate with the suction device in the previous period, and by driving the suction device in the previous period, each cell of the overexpanded core The air is sucked in and the pressure is applied from the exposed peripheral wall to bend the cell wall of each cell along the connection part, and the curved surface shape is composed of a planar aggregate of hollow columnar cells in a substantially drum shape. A honeycomb core for production is formed.

"Operation" Since the present invention comprises the above means, it operates as follows.
That is, a plate-shaped sliding member provided through a large number of through holes to communicate with the suction device, the overexpanding core held in an airtight manner between the pair of suction plates through both sides of the sliding member By driving the suction device provided in communication with the intake hole of the panel, the air existing in each cell is sucked from both open ends of the cell through the sliding members and the suction panel, The inside becomes a vacuum state. As the inside of each cell becomes a vacuum state, the overexpanded core is pressurized from its exposed peripheral wall portion. Due to this pressurization, the over-expanded core, which is sandwiched between the pair of suction disks via the sliding member in an airtight manner, is guided by the sliding member while being kept airtight, and is entirely compressed.

However, the over-expanded core has high rigidity because the cell walls that are alternately displaced by half a pitch along the ribbon direction are joined to each other, and the cell walls that are located in a straight line along the spreading direction. Has a low rigidity, and when compressed by pressure, concentrated stress acts on each connection part of the cell walls forming each cell,
In the state of the over-expanded core, the low-rigidity cell walls that were located in a straight line along the expansion direction were bent along the respective connection parts with the high-rigidity cell walls that were located along the ribbon direction, and were regular. It is formed in a zigzag shape. Each cell wall located along the spreading direction is formed in a regular zigzag shape, so that each cell is formed in a plane in a plane that is vertically and horizontally symmetrical about the center line in the longitudinal and width directions. To be done. Therefore, the over-expanded core, which is a planar aggregate of substantially rectangular cells, is molded into a curved surface forming honeycomb core made of a planar aggregate of approximately drum-shaped cells.

At the time of molding, the air in each cell of the overexpanded core is sucked through a sliding member provided through a large number of through holes so as to communicate with the suction device. Is uniformly aspirated from both open ends of the cell. Therefore, each exposed peripheral wall portion is uniformly pressed. In addition, since each cell wall is guided and moved by the sliding member during compression by pressurization, the movement is also easy. Therefore, even if the thickness of the over-expanded core is extremely thin or the size thereof is large, it is of course possible to form a high-quality curved surface forming honeycomb core, and the thickness of the over-expanded core Even if the thickness is extremely thick, it is possible to easily form a high quality curved surface forming honeycomb core.

[Examples] The present invention will be described below based on examples shown in the drawings.

FIG. 1 is a longitudinal sectional view showing a state in which an overexpanded core is set in a molding apparatus for specifically carrying out the method for molding a honeycomb core for forming a curved surface according to the method of the present invention.
The drawing is a partially cutaway perspective view of the main parts of the suction plate and the sliding member that constitute the molding apparatus.

This will be described with reference to FIGS. 4 and 7.

First, a molding apparatus for specifically carrying out the method for molding a honeycomb core for curved surface formation according to the method of the present invention will be described.

The molding apparatus 1 includes a pair of suction plates 4 and 4 which are in communication with the suction device 2 via an intake pipe 3, surface plates 5 and 5 of these suction plates 4 and 4, and an overexpanding core 20 described later.
It is composed of a pair of sliding members 9, 9 interposed between them.

Surface plates 5 of the pair of suction plates 4 and 4 facing each other,
5 includes an airtight chamber 4a formed on the upper surface and the inside thereof.
Over-expanded core that is processed to communicate with
A large number of small-diameter intake holes 6, 6 ... Are bored in such a manner that at least one intake hole 6 exists in the portion corresponding to each of the cells 21, 21. In addition, these suction plates 4 and 4 are connected to the suction device 2 at the other end of the intake pipe 3 having one end connected to a connection hole 8 formed in a part of the side frame 7 forming the airtight chamber 4a. By doing so, it is in communication with the suction device.

The sliding members 9 and 9 are made of a material having a slight elasticity, for example, a silicon rubber material, and are formed in a flat plate shape.
A large number of through holes 10, 10 having the same diameter as the intake holes 6 are provided in the respective sliding members 9, 9 in a positional relationship corresponding to the intake holes 6, 6 ... Bored in the surface plate 5 of the suction plate 4, respectively. It is provided through.

In the molding apparatus 1 of this embodiment, the sliding members 9 and 9 are arranged on the surface plate 5 of the suction disk 4 so that the through holes 10, 10 ... And the intake holes 6, 6 ... It is attached.

Therefore, according to this embodiment, it is easy to set the overexpanding core 20 when the honeycomb core 11 for forming a curved surface is formed.

The molding device 1 is configured as described above.

Next, the molding method will be described.

As shown in FIG. 7, a cell formed by further expanding a honeycomb core made of a planar aggregate of cells of a substantially regular hexagonal hollow column formed by expansion forming means in the expansion direction by a predetermined amount. A curved surface forming honeycomb core 11 shown in FIG. 4 is formed by using an over-expanding core 20 formed of a planar assembly of cells 21, 21 ... Each of which has walls 22, 23 having a bending angle of about 90 °. In molding, first, as shown in FIG. 1, the over-expanding core 20 is set between the pair of suction plates 4 and 4. The set overexpanding core 20 is the surface plate 5 of the suction plates 4 and 4,
Since it is set via the slightly elastic sliding members 9, 9 attached to 5, the airtightly held state is held between the suction plates 4, 4. Further, both open ends of the cells 21, 21, ... Of the set overexpanding core 20 are respectively provided with a through hole 10 of the sliding member 9 and an intake hole 6 of the suction plate 4 in the airtight chamber 4a communicating with the suction device 2. They are in communication with each other.

Therefore, next, by driving the suction device 2,
The air existing in the cells 21, 21, ... Of the overexpanding core 20 is gradually and uniformly sucked from both open ends of the cells 21, 21. Due to this suction, the inside of each of the cells 21, 21 ... As the inside of each of the cells 21, 21 ... Is evacuated, the over-expanded core 20 is uniformly pressurized by the atmospheric pressure from the exposed peripheral wall portion. Due to this pressurization, the overexpanding core 20, which is held in an airtight state between the pair of suction plates 4 and 4 via the sliding members 9 and 9, is guided by the sliding members 9 and 9 while maintaining the airtight state, Compressed.

At the time of compression by this pressurization, concentrated stress acts on the connection portions of the cell walls 22 and 23 forming the cells 21, 21 ... In the overexpanded core 20, so that the expansion direction in the state of the overexpanded core 20 The low-rigidity cell walls 23, 23 located in a straight line along W are connected to the respective high-rigidity cell walls 22, 22, ... Positioned along the ribbon direction L, that is, the cell walls. It is bent along the bonding edges of 22, 22 and is formed in a regular zigzag shape, that is, in the state of the cell walls 14, 14 ... In the curved surface forming honeycomb core 11. This allows overexpanded core 20
In the state of each cell 21, which had a substantially rectangular shape in a plane,
Each of the cells 21 has a constricted portion 15 in the central portion thereof and is formed into cells 12 having a substantially drum shape that is symmetrical vertically and horizontally.

Therefore, according to the molding method of the present invention, it is possible to mold the curved surface forming honeycomb core 11 including a planar aggregate of the high-quality substantially drum-shaped cells 12, 12, regardless of the simple molding method. .

FIG. 3 shows another embodiment of the suction plate and the intake pipe constituting the molding apparatus 1. The suction plate 44 in this embodiment is
The interior thereof is partitioned into a plurality of chambers (three chambers in the embodiment) by partition plates 41, 41 ... And a plurality of airtight chambers 44a, 44a. The ends of the plurality of branch pipes 43, 43 ... Branched to the other end of the intake pipe 3 having one end connected to a suction device (not shown) are provided in the plurality of airtight chambers 44a, 44a. The branch pipes 43, 43 ... Are respectively provided with switching valves 45, 45.

Therefore, according to the suction plate 44 in this embodiment, it is possible to perform suction for each of the airtight chambers 44a, 44a ... By switching the switching valves 45, 45. For example, when the size of the over-expanded core 20 is extremely large and the over-expanded core 20 is sucked over the entire surface at the same time, the movement of the cell wall during compression due to pressure is not smooth, and a high-quality curved surface forming honeycomb core is formed.
When it is difficult to mold 11, for example, by first molding a part corresponding to the airtight chamber 44a located in the central portion, and then molding a part corresponding to the airtight chamber 44a located outside thereof, Since it is possible to easily move each cell wall during compression by pressurization, it is easy to form a high quality curved surface forming honeycomb core 11 having an extremely large size.

In addition, in the suction plate 44 in this embodiment, the configuration, function and action of the other members are the same as those of the suction plate 4 in the above-mentioned embodiment, so the same reference numerals are given and the description thereof is omitted.

[Advantages of the Invention] As described above in detail, according to the method for forming a honeycomb core for forming a curved surface according to the present invention, the thickness, size, etc. of the overexpanded core before forming are very simple although the method is extremely simple. It is possible to easily form a high-quality curved surface forming honeycomb core from an over-expanded core of any configuration without being restricted by
Conventionally, there are some remarkable and great effects, such as elimination of the drawbacks of the conventional method for forming a curved surface forming honeycomb core.

[Brief description of drawings]

1 and 2 show an embodiment of the present invention,
FIG. 1 is a vertical cross-sectional view showing a state in which an overexpanded core is set in a molding apparatus for specifically carrying out the method for molding a curved surface forming honeycomb core according to the method of the present invention.
The drawing is a partially cutaway perspective view of the main parts of the suction plate and the sliding member that constitute the molding apparatus. FIG. 3 is a partially cutaway perspective view of a main part showing another embodiment of the suction plate and the intake pipe. FIG. 4 is a plan view of an essential part of a honeycomb core for forming a curved surface,
FIG. 6 and FIG. 6 are explanatory views showing a state in which a curved honeycomb core is formed by using a curved surface forming honeycomb core. FIG. 5 is a plan view of an essential part thereof, and FIG. 6 is a plan view of FIG.
FIG. 6 is a sectional view taken along line VI-VI. 7 and 8 show a conventional example of a honeycomb core for forming a curved honeycomb core.
FIG. 8 is a plan view of the essential parts of the over-expanded core, and FIG. 8 is a plan view of the essential parts of the flexible core. 1 ... Molding device, 2 ... Suction device, 3 ... Intake pipe, 4,
44 …… Suction plate, 4a, 44a …… Airtight chamber, 5 …… Surface plate, 6
…… Intake hole, 7 …… side frame, 8 …… connection hole, 9 …… sliding member, 10 …… through hole, 11 …… curved surface forming honeycomb core, 12 ・ ・ ・
… Cells (cells of honeycomb core for curved surface formation), 13, 14 ……
Cell wall (honeycomb core cell wall for curved surface formation), 20 …… Overexpanding core, 21 …… Cell (overexpanding core cell), 22, 23 …… Cell wall (overexpanding core cell wall), 41 …… ... Partition plate, 43 ... Branch pipe, 45 ... Switching valve, W ... Spreading direction, L ... Ribbon direction.

Claims (1)

[Claims] 1. A honeycomb core formed of a planar assembly of hollow columnar cells each having a substantially regular hexagonal shape formed by expansion forming means, and each cell formed by further expanding the honeycomb core in the expansion direction. A plate-shaped sliding member in which a rectangular overexpanding core is provided between a pair of suction plates having a plurality of suction holes communicating with a suction device and through a plurality of through holes for communicating with the suction device. Airtightly sandwiched via, while sucking the air in each cell of the overexpand core by driving the suction device,
A curved surface characterized by pressurizing from the exposed peripheral wall portion to bend the cell wall of each cell along the connection portion, respectively, to form a honeycomb core made of a planar aggregate of hollow columnar cells having a substantially drum shape in a plane. Method for forming honeycomb core for forming.