JP7210248B2 - panel structure and aircraft - Google Patents

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a panel structure and an aircraft that close an opening formed in a matrix structure made of composite material.

Conventionally, a composite material structure is known that includes an access panel that can be removed from an access hole formed in an aircraft wing (see, for example, Patent Document 1). The access panel is fixed to the composite ribs or stringers by sandwiching them using clamp angles or by fastening them with fasteners.

JP 2012-162148 A

Fasteners, including nut plates and bolts, may be used to attach access panels to access holes. In this case, the nut plate is attached to a wing body such as a main wing made of composite material. However, when attaching the nut plate, it is necessary to form an attachment hole for attaching the nut plate in the wing body, which is a composite material. These mounting holes are long and thin hollow cylinders, making it difficult to machine composite materials and causing an increase in processing costs. I give. In order to increase the strength around the access hole, it is possible to increase the thickness around the access hole. Therefore, it is necessary to gradually change the thickness of the plate, resulting in an increase in weight.

SUMMARY OF THE INVENTION Accordingly, an object of the present invention is to provide a panel structure and an aircraft that can be made lighter while reinforcing the periphery of an opening formed in a base structure made of a composite material.

A panel structure of the present invention comprises a base structure made of a composite material and having an opening formed thereon, and a first portion annularly provided along the edge of the opening and fixed to the base structure. , a second portion protruding from the first portion to the inside of the opening, a joining member constructed using a metal material, and covering the opening, the second portion of the joining member and a panel member detachably fixed to the second part.

According to this configuration, since the joint member can be provided along the edge of the opening, the periphery of the opening can be reinforced. Therefore, it is not necessary to increase the thickness of the base structure around the opening for reinforcement, so that the weight can be reduced. Moreover, since the panel member can be fixed to the joint member instead of the base structure which is a composite material, the panel member can be appropriately attached to the joint member.

Further, it is preferable that the joint member and the panel member are strength members having strength capable of transmitting the load from the base structure.

According to this configuration, by using the joint member and the panel member as strength members, they can function as members that transmit the load from the base structure. The joint member and the panel member have a strength equal to or greater than that of the base structure, for example, the same strength as that of the base structure. Moreover, the joint member and the panel member are configured to contain, for example, a metal material.

Moreover, it is preferable that the opening has an opening shape that is long in one direction and short in a direction orthogonal to the one direction in the plane in which the opening is formed.

According to this configuration, the stress concentration around the opening can be alleviated by forming the opening so that the load direction in the base structure is in one direction of the opening.

In addition, the inner end of the opening of the base structure and the outer end of the panel member are fixed so as to face each other. It is preferable that the thickness increases toward the portion where the two face each other.

According to this configuration, the thickness of the joint member can be increased at the portion where the load transmitted from the base structure is large. In other words, it is possible to reduce the thickness of the joint member at the portion where the load transmitted from the base structure is small. Therefore, the load can be appropriately transmitted from the base structure to the panel member via the joint member, and the weight can be reduced by reducing the thickness of a part of the structure.

An aircraft according to the present invention includes a fuselage and the above-described panel structure provided on the fuselage.

According to this configuration, when, for example, the main wing of an airframe is applied as the mother structure, the joint member can reinforce the periphery of the opening, and the weight increase of the main wing due to the provision of the panel structure can be suppressed.

FIG. 1 is a schematic diagram of an aircraft provided with the panel structure of Embodiment 1. FIG. FIG. 2 is a cross-sectional view schematically showing the panel structure of Embodiment 1. FIG. FIG. 3 is a plan view schematically showing the panel structure of Embodiment 1. FIG. FIG. 4 is a plan view schematically showing the panel structure of Embodiment 2. FIG. FIG. 5 is a cross-sectional view schematically showing the panel structure of Embodiment 3. FIG. FIG. 6 is a plan view schematically showing the panel structure of Embodiment 3. FIG.

EMBODIMENT OF THE INVENTION Below, embodiment which concerns on this invention is described in detail based on drawing. In addition, this invention is not limited by this embodiment. In addition, components in the following embodiments include components that can be easily replaced by those skilled in the art, or components that are substantially the same. Furthermore, the components described below can be combined as appropriate, and when there are multiple embodiments, each embodiment can be combined.

[Embodiment 1]
A panel structure 10 according to Embodiment 1 is provided in an aircraft 1 . FIG. 1 is a schematic diagram of an aircraft provided with the panel structure of Embodiment 1. FIG. As shown in FIG. 1 , the panel structure 10 according to Embodiment 1 is a structure that closes an access hole for accessing a fuel tank provided on a main wing 16 of an aircraft 1 . First, before describing the panel structure 10, the aircraft 1 will be described.

An aircraft 1 of Embodiment 1 includes a fuselage 3 and a panel structure 10 provided on the fuselage 3 .

The fuselage 3 includes a fuselage 15 and main wings 16 . The fuselage 15 is a tubular portion extending in the roll axis direction, which is the direction connecting the nose side and the aft side of the aircraft 1 . The main wing 16 is provided near the center of the fuselage 15 and is a wing body extending outward from the fuselage 15 in the pitch axis direction orthogonal to the roll axis direction. In Embodiment 1, the main wing 16 is configured using a composite material and serves as a mother structure on which the panel structure 10 is provided. In the first embodiment, the panel structure 10 is applied to the main wing 16 of the aircraft 1. However, the panel structure 10 may be applied to any composite material as long as the base structure is a composite material. It may be applied to a windmill or the like configured using

FIG. 2 is a cross-sectional view schematically showing the panel structure of Embodiment 1. FIG. FIG. 3 is a plan view schematically showing the panel structure of Embodiment 1. FIG. The panel structure 10 will be described with reference to FIGS. 2 and 3. FIG.

The panel structure 10 includes a main wing 16 serving as a base structure, a joint member 21 , an access panel 22 , a first fastener 23 , a second fastener 24 , and a sealing material 25 .

The main wing 16 is formed using a composite material in which reinforcing fibers such as carbon fibers are impregnated with resin and cured. The surface of the main wing 16 is an aerodynamic surface. An access hole (opening) 31 is formed on the surface of the main wing 16 for a worker to access a fuel tank formed inside the main wing 16 . The access hole 31 is, for example, a circular opening, and has a size that allows a worker to come and go inside and outside the main wing 16 . Here, the fuel tank inside the main wing 16 has a bag structure. The bag structure is a sealed structure in which the internal space is a sealed space, and when the access hole 31 is closed, the access panel 22 can be attached and detached only from the outside of the main wing 16 .

The joint member 21 is provided on the inner surface opposite to the surface (outer surface) of the main wing 16 . The joint member 21 is formed in an annular shape along the edge of the access hole 31 . That is, the joint member 21 is formed in a disk shape, and has a shape in which a circular opening 35 is formed in the center. The joint member 21 has an outer peripheral portion (first portion) 21a that is on the outer peripheral side, and an inner peripheral portion (second portion) 21b that is provided on the inner peripheral side of the outer peripheral portion 21a.

The outer peripheral portion 21 a is a portion that overlaps the main wing 16 and is a portion that is fixed to the main wing 16 . The inner peripheral portion 21b is a portion protruding inside the access hole 31 from the outer peripheral portion 21a. The inner peripheral portion 21b is a portion that overlaps the access panel 22, and is a portion to which the access panel 22 is fixed.

The access panel 22 is provided on the surface side of the main wing 16 . Since the surface of the main wing 16 is an aerodynamic surface, the access panel 22 is formed such that the outer surface of the access panel 22 is flush with the surface of the main wing 16 . The access panel 22 is formed in a disk shape, and has a size that fits in the access hole 31 and a shape that is larger than the opening 35 of the joint member 21 . Therefore, the inner end of the access hole 31 and the outer end of the access panel 22 are arranged and fixed in a state of facing each other.

Here, the joint member 21 and the access panel 22 are configured including a metal material, and are configured as strength members capable of transmitting the load from the main wing 16 . For example, the joint member 21 and the access panel 22 have a plate thickness that allows the load from the main wing 16 to be transmitted. Further, the strength of the joint member 21 and the access panel 22 is greater than or equal to the strength of the main wing 16, and is approximately the same as that of the main wing 16, for example.

The first fastener 23 fastens and fixes the main wing 16 and the outer peripheral portion 21 a of the joint member 21 . Therefore, the first fastener 23 is provided at a portion where the main wing 16 and the outer peripheral portion 21a of the joint member 21 overlap. The first fastener 23 is a permanent combination fastener, and is configured to be difficult to remove non-destructively after being fastened and fixed. A plurality of first fasteners 23 are arranged in a circumferential direction along the edge of the access hole 31 . The first fasteners 23 are arranged such that the interval between the first fasteners 23 adjacent in the circumferential direction is a predetermined interval defined in advance. In Embodiment 1, the plurality of first fasteners 23 are arranged in a row along the circumferential direction.

The first fastener 23 includes a head portion 23a, a shaft portion 23b, and a collar 23c. The first fastener 23 is inserted through a main wing-side through-hole 37 formed in the main wing 16 and an outer peripheral-side through-hole 38 formed in the outer peripheral portion 21 a of the joint member 21 . The main wing-side through-hole 37 and the outer peripheral-side through-hole 38 have the same diameter. The head 23 a is countersunk and engages the main wing 16 . The shaft portion 23 b is inserted through the main wing side through hole 37 and the outer peripheral side through hole 38 . The collar 23c is fastened to the shaft portion 23b. By fastening the first fastener 23, the main wing 16 and the joint member 21 are fixed by being sandwiched between the head portion 23a and the collar 23c of the first fastener 23. As shown in FIG.

The second fastener 24 fastens and fixes the inner peripheral portion 21 b of the joint member 21 and the access panel 22 . Therefore, the second fastener 24 is provided at a portion where the inner peripheral portion 21b of the joint member 21 and the access panel 22 overlap. The second fastener 24 is a detachable fastener that allows the access panel 22 to be fixed to and released from the joint member 21 . A plurality of second fasteners 24 are arranged in a circumferential direction along the edge of the access panel 22 . The second fasteners 24 are arranged such that the interval between the second fasteners 24 adjacent in the circumferential direction is a predetermined interval defined in advance. In Embodiment 1, the plurality of second fasteners 24 are arranged in a row along the circumferential direction.

The second fastener 24 includes a nut plate 41 and bolts 42 . The nut plate 41 is formed with fastening holes for fastening bolts 42 and is attached to the inner surface side of the joint member 21 . The nut plate 41 is attached to the inner peripheral portion 21 b of the joint member 21 using fastening pins 45 . The bolt 42 includes a head portion 42a and a shaft portion 42b. The bolt 42 is inserted through an inner peripheral side through hole 47 formed in the inner peripheral portion 21 b of the joint member 21 and a panel side through hole 48 formed in the access panel 22 . The inner circumference side through hole 47 and the panel side through hole 48 are through holes having the same diameter. Head 42 a is countersunk and engages access panel 22 . The shaft portion 23 b is inserted through the inner peripheral side through hole 47 and the panel side through hole 48 and fastened to the fastening hole of the nut plate 41 . The joint member 21 and the access panel 22 are fixed by being sandwiched between the nut plate 41 and the head portion 42 a of the bolt 42 by fastening the second fastener 24 .

Here, regarding the outer peripheral side through hole 38 (the main wing side through hole 37) and the inner peripheral side through hole 47 (the panel side through hole 48) of the joint member 21, the outer peripheral side through hole 38 is the inner peripheral side through hole 47 , the number of through holes 47 is larger than that of the inner peripheral side through holes 47 .

Moreover, the mounting hole 46 to which the fastening pin 45 for mounting the nut plate 41 is fastened has a length in the depth direction longer than its diameter, and is elongated. On the other hand, the main wing-side through hole 37 for attaching the first fastener 23 has a length in the depth direction shorter than the diameter, and is formed thick and short.

The sealing material 25 fills the gap between the main wing 16 and the joint member 21 to make the inside of the main wing 16 an airtight space. The sealing material 25 is provided on the inner surface side of the main wing 16 so as to cover the radially outer end of the joint member 21 .

In the panel structure 10 described above, when the access panel 22 is removed, the bolts 42 of the second fasteners 24 are released from the nut plate 41 , thereby releasing the access panel 22 from the joining member 21 . On the other hand, when attaching the access panel 22 , the access panel 22 is fixed to the joint member 21 by fastening the bolts 42 of the second fasteners 24 to the nut plate 41 .

As described above, according to the first embodiment, since the joint member 21 can be provided along the edge of the access hole 31, the periphery of the access hole 31 can be reinforced. Therefore, it is not necessary to increase the thickness of the main wing 16 around the access hole 31 for reinforcement, so that the weight can be reduced. Moreover, since the access panel 22 can be fixed to the joint member 21 instead of the main wing 16 which is a composite material, the access panel 22 can be properly attached to the joint member 21 .

Further, according to the first embodiment, by using the joint member 21 and the access panel 22 as strength members, they can function as members that transmit the load from the main wing 16 .

Further, according to the first embodiment, by applying the panel structure 10 to the main wing 16 of the aircraft 1, the area around the access hole 31 can be reinforced by the joint member 21, and the provision of the panel structure 10 increases the weight of the main wing 16. can be suppressed.

In the first embodiment, the surface of the main wing 16 is an aerodynamic surface, so the joint member 21 is provided on the inner surface side of the main wing 16. The member 21 may be provided on either the inner surface or the outer surface.

Further, in Embodiment 1, the main wing 16 and joint member 21 are fixed using the first fastener 23, which is a permanent fastener, but the main wing 16 and joint member 21 are fixed using an adhesive. you can go

Further, in Embodiment 1, since the access hole 31 has a circular shape, the joint member 21 has an annular shape and the access panel 22 has a circular shape, but the configuration is not limited to this. The access hole 31 may have a square shape. In this case, the joining member 21 may have a square frame shape and the access panel 22 may have a square shape.

[Embodiment 2]
Next, a panel structure 50 according to Embodiment 2 will be described with reference to FIG. In order to avoid redundant description, in the second embodiment, portions different from those in the first embodiment will be described, and portions having the same configuration as in the first embodiment will be described with the same reference numerals. FIG. 4 is a plan view schematically showing the panel structure of Embodiment 2. FIG.

In the panel structure 50 of Embodiment 2, the access hole 51 has an opening shape that is long in one direction and short in a direction orthogonal to the one direction in the plane in which the access hole 51 is formed. Specifically, the access hole 51 is formed in an elliptical shape in which the major axis direction is the direction of the load transmitted from the main wing 16 and the minor axis direction is the direction perpendicular to the load direction in the plane in which the access hole 51 is formed. It is In this case, the joint member 53 is formed in an elliptical ring shape along the edge of the access hole 51 . The access panel 55 also has an elliptical shape that is complementary to the shape of the access hole 51 .

As described above, according to the second embodiment, by forming the access hole 51 so that the direction of the load transmitted from the main wing 16 is aligned with the longitudinal direction of the access hole 51, the stress concentration around the access hole 51 increases. can be mitigated.

[Embodiment 3]
Next, a panel structure 60 according to Embodiment 3 will be described with reference to FIGS. 5 and 6. FIG. Note that in the third embodiment, portions different from those in the first and second embodiments will be described in order to avoid redundant description, and portions having the same configurations as in the first and second embodiments will be described with the same reference numerals. FIG. 5 is a cross-sectional view schematically showing the panel structure of Embodiment 3. FIG. FIG. 6 is a plan view schematically showing the panel structure of Embodiment 3. FIG.

In the panel structure 10 of Embodiment 1, the first fasteners 23 and the second fasteners 24 are arranged in a row along the circumferential direction. A plurality of rows (for example, two rows in Embodiment 3) of first fasteners 23 and second fasteners 24 are used. The panel structure 60 of Embodiment 3 has a structure used when the load from the main wing 16 cannot be transmitted by the first fastener 23 and the second fastener 24 in a row in the panel structure 10 of Embodiment 1. It's becoming In other words, the panel structure 60 of Embodiment 3 is configured to transmit the load even when the load from the main wing 16 is large.

As in the first embodiment, the panel structure 60 of the third embodiment includes the main wing 16 serving as the base structure, the joint member 63, the access panel 22, the first fastener 23, the second fastener 24, A sealing material 25 is provided. Here, the main wing 16, the access panel 22, and the sealing material 25 are substantially the same in configuration as in the first embodiment, and therefore description thereof is omitted.

The joint member 63 is formed in an annular shape along the edge of the access hole 31 . Also, the thickness of the joint member 63 increases toward the portion where the inner end of the access hole 31 and the outer end of the access panel 22 face each other. Specifically, the joint member 63 has a radially central portion where the inner end portion of the access hole 31 and the outer end portion of the access panel 22 face each other. The joint member 63 includes a thick portion 63a having a large thickness at the central portion in the radial direction, an inner thin portion 63b having a small thickness at the inner end portion in the radial direction, and an outer portion having a small thickness at the outer end portion in the radial direction. and a thin portion 63c. The joining member 63 has a step between the thick portion 63a and the inner thin portion 63b, and a step between the thick portion 63a and the outer thin portion 63c. That is, the joint member 63 is formed stepwise by the thick portion 63a, the inner thin portion 63b, and the outer thin portion 63c.

The first fastener 23 is a permanent coupling fastener as in the first embodiment, and is provided at a portion where the main wing 16 and the outer peripheral portion 21a of the joint member 21 overlap. In Embodiment 3, the plurality of first fasteners 23 arranged in a row along the circumferential direction are arranged side by side in two rows in the radial direction. Specifically, in the first fasteners 23, the row of the first fasteners 23 on the outer peripheral side is provided at a portion where the main wing 16 and the outer thin portion 63c of the joint member 21 overlap. In addition, in the first fasteners 23 , the row of first fasteners 23 on the inner peripheral side is provided at a portion where the main wing 16 and the thick portion 63 a of the outer peripheral portion 21 a of the joint member 21 overlap. The main wing-side through-holes 37 and the outer peripheral-side through-holes 38 are formed according to the positions where the first fasteners 23 are provided.

The second fastener 24 is a fastener including a nut plate 41 and a bolt 42 as in the first embodiment, and is provided at a portion where the inner peripheral portion 21b of the joint member 21 and the access panel 22 overlap. In Embodiment 3, the plurality of second fasteners 24 arranged in a row along the circumferential direction are arranged side by side in two rows in the radial direction. Specifically, in the second fasteners 24 , the row of second fasteners 24 on the inner peripheral side is provided at a portion where the inner thin portion 63 b of the joining member 21 and the access panel 22 overlap. In the second fasteners 24, the row of the second fasteners 24 on the outer peripheral side is provided at a portion where the access panel 22 and the thick portion 63a of the inner peripheral portion 21b of the joining member 21 overlap. The inner circumference side through hole 47 and the panel side through hole 48 are formed according to the position where the second fastener 24 is provided.

As described above, according to the third embodiment, it is possible to increase the thickness of the joint member 63 at the portion where the load transmitted from the main wing 16 is large. In other words, the thickness of the joint member 63 can be reduced at the portion where the load transmitted from the main wing 16 is small. Therefore, the load can be appropriately transmitted from the main wing 16 to the access panel 22 via the joint member 63, and the thickness of the panel structure 60 can be partially reduced, so that the weight of the panel structure 60 can be reduced. can be done.

Although the joint member 63 has a stepped shape in the third embodiment, it is not limited to this configuration. The joint member 63 has a thick central portion in the radial direction, a thickness that decreases continuously from the radial center toward the inner end, and a thickness that decreases from the radial center toward the outer end. You may form so that it may become thin continuously.

Reference Signs List 1 aircraft 3 fuselage 10 panel structure 15 fuselage 16 main wing 21 joint member 21a outer peripheral portion 21b inner peripheral portion 22 access panel 23 first fastener 24 second fastener 25 sealing material 31 access hole 35 opening 37 main wing-side through hole 38 outer periphery Side through hole 41 Nut plate 42 Bolt 45 Fastening pin 47 Inner circumference side through hole 48 Panel side through hole 50 Panel structure 51 Access hole 53 Joint member 55 Access panel 60 Panel structure 63 Joint member

Claims (5)

a base structure made of a composite material with openings;
A first portion provided annularly along the edge of the opening and fixed to the base structure, and a second portion protruding from the first portion to the inside of the opening. together with a joint member configured using a metal material;
a panel member that covers the opening and is detachably fixed to the second portion of the joint member;
a first fastener that fastens and fixes the base structure and the first portion of the joining member;
a second fastener that fastens and fixes the second portion of the joint member and the panel member ;
The second fastener is
a nut plate attached to the inner surface side of the second portion of the joint member;
A panel structure including: a bolt inserted through the second portion of the joint member and the panel member and fastened to the nut plate . 2. The panel structure according to claim 1, wherein said joint member and said panel member are strength members having strength capable of transmitting a load from said base structure. 3. The panel structure according to claim 1, wherein the opening has an opening shape that is long in one direction and short in a direction orthogonal to the one direction in the plane in which the opening is formed. an inner end portion of the opening of the base structure and an outer end portion of the panel member are fixed so as to face each other;
The panel structure according to any one of claims 1 to 3, wherein the joint member has a thickness that increases toward a portion where the inner end portion and the outer end portion face each other. Airframe and
and a panel structure according to any one of claims 1 to 4, which is provided on the fuselage.

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