JPH0637100B2 - Carbon fiber reinforced plastic structure - Google Patents

Description

[Detailed Description of the Invention] Outline Regarding a carbon fiber reinforced plastic structure, the rigidity and the supported object for supporting a heavy structure without causing electrolytic corrosion with other metals even in a high vacuum environment such as outer space. The purpose of the present invention is to provide a carbon fiber reinforced plastic structure having heat insulating properties that makes it difficult for the generated heat to be transferred to other parts.In a structure in which prepreg materials of carbon fiber reinforced plastic are laminated, the fiber direction is A core portion of a cross section of a structure, which is formed by laminating a prepreg material and a plurality of fiber directions in an arbitrary direction, and the plurality of fiber directions having a uniform strength against a force or moment in each direction. Is made of prepreg material that has uniform strength against the forces and moments in each direction, and both surface sides are mainly made of prepreg material with one direction of fiber. Together constituting provided glass fiber-reinforced plastic parts in contact with dissimilar metals.

TECHNICAL FIELD The present invention relates to a carbon fiber reinforced plastic structure.

In an artificial satellite launched into outer space, a supporting structure that supports heat-generating components such as a motor is exposed to a special environment in outer space, and therefore, a characteristic and structure suitable for this environment are required. . That is, the support structure on which the heat-generating component is mounted is placed on the base, but when the heat from the heat-generating component is conducted to the base via the support structure, other components mounted on this base are Since it is deformed by thermal expansion and its dimensional accuracy is changed, the support structure is required to have a heat insulating property that effectively prevents heat conduction in the base direction. Further, when such a support structure is mounted on an artificial satellite, a gravitational acceleration of 15 to 20 G is applied when the rocket is launched, and therefore a strength sufficient to withstand a gravitational acceleration 15 to 20 times that of the ground is required. . Therefore, there is a demand for a support structure having such characteristics that it can be used in outer space.

2. Description of the Related Art FIG. 3 is a schematic view of a conventional support structure having heat insulating properties, in which a supported object 3 having a heat generating portion 4 such as a heater or a motor is provided on a support structure 1 having a heat insulating portion 2. It is mounted and the support structure 1 is mounted on the base 5. Reference numeral 6 denotes a heat radiating member such as a heat pipe for radiating the heat generated in the heat generating portion 4 to outer space.

The heat generated in the heat radiating section 4 escapes to the outside through the heat radiating paths A and B, but the heat transfer to the vess 5 is caused by the thermal expansion of other parts mounted on the base 5, so that the positional accuracy of the heat is distorted. The heat conduction in the direction is prevented by the heat insulating portion 2. In such a support structure 1, mica, GFRP (glass fiber reinforced plastic), rubber, glass or the like having heat insulating properties is used as the material of the heat insulating portion 2. The other part of the support structure 1 is made of a metal such as Al or SUS.

Problems to be Solved by the Invention If an attempt is made to mount such a structure on an artificial satellite, a gravitational acceleration of 15 to 20 G is applied to the support structure at the time of launch of the rocket, and vibration is generated in a frequency range within a certain range. , The following problems occur.

(B) When the resonance frequency and the excitation frequency of the structure are close to each other, the structure is destroyed due to the resonance phenomenon.

(B) The strength is required to withstand the gravitational acceleration 15 to 20 times that on the ground.

(C) It is necessary to reduce the weight of the satellite as a payload.

(D) In a high vacuum state of outer space, when a structure is made of metal, there is a problem that galvanic corrosion occurs between dissimilar metals in contact with the structure.

In (a) and (b), it is necessary to increase the volume and mass of the structure in order to increase its strength, which is a contradictory requirement to (c).

The present invention has been made in view of the above points, and an object thereof is a rigidity for supporting a heavy structure without causing electrolytic corrosion with other metals even in a high vacuum environment such as outer space. Another object of the present invention is to provide a carbon fiber reinforced plastic having heat insulating properties that makes it difficult to transfer the heat generated from the supported object to other parts.

Means for Solving Problems As a material having strength and heat insulation properties, carbon fiber reinforced plastic (hereinafter referred to as CFR) having a large Young's modulus and a low thermal conductivity.
(Referred to as “P”) and to further increase the resonance frequency of the structure, a CFRP laminated structure having a small density and a large Young's modulus is used. Regarding the laminated structure, since a large moment is generated on the surface side, prepreg materials 22 and 24 having a high strength and a high Young's modulus and a fiber direction of one direction are arranged on the surface side, and as a core material, a flexural rigidity rather than a flexural rigidity is used. In order to have uniform strength against a force or moment in the direction, a prepreg material 26 having fiber directions that are mainly in the same direction is arranged to have a laminated structure.
In addition, GFRP (glass fiber reinforced plastic), which is an insulator, is attached to the part where the structure comes into contact with dissimilar metals such as bolts and bases to prevent direct contact between the carbon fiber of the structure and other metals. To do.

Since the working structure is a laminated structure of CFRP, it is possible to sufficiently reduce the weight as an artificial satellite loading object, and to use a high-strength C
Since the FRP has a special laminated structure, it can withstand the gravity acceleration of 15 to 20 G applied at the time of launching the rocket. Also, due to the special laminated structure of CFRP, the resonance phenomenon of the structure can be effectively prevented. Furthermore, by attaching GFRP to the portion that comes into contact with the dissimilar metal, it is possible to effectively prevent electrolytic corrosion in outer space.

Embodiments Embodiments of the present invention will be described in detail below with reference to the drawings.

FIG. 1 is a sectional view of a CFRP structure according to an embodiment of the present invention.
2, the inner surface portion 14 and the outer surface portion 16 are formed by laminating CFRP having different types and characteristics. FIG. 2 shows a CFRP prepreg material for molding the structure of FIG. 1, and the line in the drawing shows the fiber direction. 2A and 2B show a state in which the same CFRP prepreg material is arranged with a 90 ° offset. In order to mold the core portion 12, the inner surface portion 14 and the outer surface portion 16 of FIG. 1, the combination of the prepreg materials shown in FIG. 2 is changed. In the inner surface 14 and the outer surface portion 16,
A large number of prepreg materials 22 and 24 having a unidirectional fiber direction are used so as to be strong against the bending moment, and the bending rigidity is improved. However, if only the prepreg materials 22 and 24 whose fiber direction is one direction are frequently used, the prepreg material 26 of FIGS. 2C and 2D is appropriately used because it becomes weak against the force (shearing force) in the direction perpendicular to the fiber direction. Combined as a reinforcing material. On the other hand, with respect to the core portion 12, the fiber direction is not set to one direction, and the fiber direction is uniformly set to a plurality of arbitrary directions so as to have a uniform strength against a force and a moment in each direction rather than bending rigidity. The prepreg material 26 shown in FIGS. 2C and 2D is frequently used.

Reference numeral 18 denotes a bolt hole, which is used to mount a supported object having a heat generating portion (not shown) on the structure 10 for bolting,
Used to bolt structure 10 to base 20. The bolt holes 18, the uppermost layer surface of the structure 10 and the lowermost surface where the structure 10 contacts the base 20 are insulators G.
The prepreg material 30 of FRP is attached. This GF
As the RP prepreg material, it is desirable to use a prepreg material in which the fiber directions are crossed as shown in FIG. Further, the bolt through hole 18 has a structure in which, instead of attaching GFRP, the carbon fiber of CFRP is escaped and knitted so that the carbon fiber of CFRP does not appear on the surface, and the resin component of CFRP is in contact with the bolt mountain portion. May be.

The CFRP and GFRP prepreg materials have a thickness of about 0.2 mm, and in order to mold the structure of FIG. Then, the prepreg materials 22 and 24 as shown in FIG. 2 are laminated and molded by the SMC method or the hand lay-up method of molding by applying heat and pressure.

The heat insulating property of the structure 10 configured as described above is
Since the prepreg material is laminated, the heat conductivity in the thickness direction of the structure is poor and the heat insulating property is excellent. Further, since the inner surface portion 14 and the outer surface portion 16 are made of a high elastic material, the heat conduction is good, but the heat conduction can be sufficiently suppressed by reducing the cross-sectional area of these portions.

According to the present embodiment, the strength is 3 to 5 of the aluminum structure due to the structure in which CFRP and GFRP are laminated.
The mass is about 1/2, and sufficient performance can be obtained as a heat insulating material.

EFFECTS OF THE INVENTION Since the CFRP structure of the present invention is configured as described in detail above, it does not cause galvanic corrosion with other metals even when it is used in outer space, and has sufficient heat insulation properties and sufficient rigidity. Has the effect of having. This makes it particularly suitable for use in special environments in outer space.

[Brief description of drawings]

FIG. 1 is a sectional view of an embodiment of the present invention, FIG. 2 is a perspective view of various prepreg materials for molding the structure of the embodiment, and FIG. 3 is a schematic view of a conventional support structure having heat insulating properties. is there. 1 ... Support structure, 2 ... Insulation part, 3 ... Supported object, 4 ... Heat generating part, 5 ... Base, 6 ... Heat dissipation member, 10 ... Support structure, 12 ... Core part, 14 ... inner surface part, 16 ... outer surface part, 18 ... bolt hole, 20 ... base, 22, 24, 26 ... prepreg material, 30 ... GFRP.

Claims (1)

[Claims] 1. A structure in which prepreg materials made of carbon fiber reinforced plastic are laminated, and a prepreg material (22, 24) having a unidirectional fiber direction and a plurality of fiber directions in arbitrary directions, and the plurality of fiber directions are The core part (12) of the cross section of the structure is composed mainly of the prepreg material (26) that has uniform strength against the forces and moments in each direction. And uniform prepreg material (26)
The prepreg material (22,24) whose fiber direction is unidirectional is mainly used for both surface sides (14,16), and glass fiber reinforced plastic is applied to the part that comes into contact with dissimilar metals.
A carbon fiber reinforced plastic structure having (30).