Fiber-reinforced composite frame

Abstract

To provide a fiber-reinforced composite material frame that suppresses the generation of buckling and improves bending strength.SOLUTION: A fiber-reinforced composite material frame 1 comprises: a compression surface part 2 where a compression stress is generated along a longitudinal direction DL when a bending load to bend the frame 1 in a short direction DS orthogonal to the longitudinal direction DL of the frame 1 is inputted to the frame 1; and a side surface part 3 extending in the short direction DS from a corner part 5 adjacent to a compression surface part 2. The compression surface part 2 comprises longitudinal direction orientation layers 11 on which reinforced fibers 11a are oriented in the longitudinal direction DL. A surface layer part of the side surface part 3 is composed of short direction orientation layers 12 as different direction orientation layers on which reinforced fibers 12a are oriented in a direction different from the longitudinal direction DL.SELECTED DRAWING: Figure 3

Description

[Technical field]

[0001] The present invention relates to a fiber-reinforced composite frame. [Background technology]

[0002] 2. Description of the Related Art Conventionally, for frames constituting the body of a vehicle, etc., a fiber-reinforced composite frame manufactured from a lightweight and highly rigid fiber-reinforced composite material has been used.

[0003] For example, the fiber-reinforced composite frame described in Patent Document 1 has a quasi-isotropic structure that allows it to withstand input loads from all directions, and specifically, has a structure formed by stacking multiple fiber orientation layers in which the reinforcing fibers are oriented in different directions.

[0004] Furthermore, in this frame, in order to improve the rigidity of the corners of the frame, the lamination of the fiber orientation layers at the corners of the frame cross section is increased to locally increase the thickness of the corners. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] JP 2015-193362 A Summary of the Invention [Problem to be solved by the invention]

[0006] However, even in a structure in which the number of fiber-oriented layers is increased at the corners, as in the frame described above, it is difficult to prevent a problem unique to fiber-reinforced composite frames, namely buckling caused by delamination at the corners.

[0007] That is, when a bending load is applied to a fiber-reinforced composite frame, delamination occurs between the fiber-oriented layers at the corners of the frame cross section, and cracks occur starting from the delaminated corners in the fiber-oriented layers of the frame on the surface where compressive stress acts (i.e., the inner curved surface of the bent frame) and on the adjacent surfaces, causing buckling of the frame. If buckling of the frame occurs, the bending strength will be significantly reduced. Therefore, the frame described in the above Patent Document 1 cannot prevent the occurrence of such a phenomenon.

[0008] The present invention has been made in consideration of the above circumstances, and has an object to provide a fiber-reinforced composite frame that suppresses the occurrence of buckling and improves bending strength. [Means for solving the problem]

[0009] The fiber-reinforced composite frame of the present invention has a closed cross section having a plurality of corners, and is extended in a predetermined direction. The frame has a compression surface portion in which a compressive stress is generated along the longitudinal direction when a bending load that bends the frame in a lateral direction perpendicular to the longitudinal direction of the frame is input to the frame, and a side portion extending in the lateral direction from the corner adjacent to the compression surface portion, the compression surface portion having a longitudinal orientation layer in which reinforcing fibers are oriented in the longitudinal direction, Inside and outside The surface layer portion is Short Reinforcement fibers are oriented in the direction Short side direction Consists of an alignment layer The side surface portion includes a 45-degree oriented layer in which reinforcing fibers are oriented in a direction inclined at 45 degrees to the longitudinal direction, and a -45-degree oriented layer in which reinforcing fibers are oriented in a direction inclined at -45 degrees to the longitudinal direction, and the 45-degree oriented layer and the -45-degree oriented layer are disposed in a central portion in the thickness direction of the side surface portion relative to the short-side oriented layer. It is characterized by:

[0010] In this configuration, when a bending load is input to the frame that bends the frame in a direction perpendicular to the longitudinal direction of the frame, a compressive stress is generated in the compression surface portion along the longitudinal direction of the frame. Since the compression surface portion has a longitudinally oriented layer along the longitudinal direction of the frame, the compression surface portion can withstand high compressive stress, and the buckling strength of the compression surface portion can be improved. At the same time, the bending rigidity can also be improved. The surface layer portion of the side portion is composed of a different-direction oriented layer in which reinforcing fibers are oriented in a direction different from the longitudinal direction (for example, in the short direction of the frame in the side portion or in an oblique direction inclined to the longitudinal direction of the frame). Therefore, the side portion can withstand high shear stress and bending stress, and deformation of the side portion (especially buckling deformation) can be suppressed. In this configuration, even if delamination occurs at the corners of the frame, it is possible to suppress the progression of cracks to the compression surface portion and the side portion, and it is possible to increase the buckling strength of the frame. As a result, it is possible to avoid buckling of the entire frame and improve the bending strength of the frame. In addition, in the above configuration, since the surface layer of the side portion is composed of a short-side direction oriented layer, it is possible to improve the rigidity of the side portion in the short side direction (e.g., bending rigidity against a load in the direction of crushing in the short side direction). Furthermore, in the above configuration, the side portion has a 45 degree orientation layer and a -45 degree orientation layer, and the 45 degree orientation layer and the -45 degree orientation layer are arranged in the center in the thickness direction of the side portion relative to the short side orientation layer, thereby making it possible to improve the shear rigidity of the side portion.

[0011] In the present invention, the "surface layer" of the side surface portion means the surface layer portions on the inside and outside of the cross section of the frame.

[0012] In the above-mentioned fiber-reinforced composite frame, The longitudinal orientation layer is arranged on the inner and outer surface layers of the compression surface portion, and the compression surface portion further includes a short-side orientation layer in which reinforcing fibers are oriented in the short-side direction, and the short-side orientation layer is arranged in a central portion in the thickness direction of the compression surface portion relative to the longitudinal orientation layer. It is preferable.

[0016] In the above-mentioned fiber-reinforced composite frame, the frame further comprises a tensile surface portion extending in the longitudinal direction at a position spaced from the compression surface portion and in which tensile stress is generated along the longitudinal direction when the bending load is input to the frame, and it is preferable that the tensile surface portion comprises the longitudinal orientation layer.

[0017] According to this configuration, when a bending load is applied to the frame, a tensile stress is generated along the longitudinal direction of the frame in the tensile surface portion spaced apart from the compression surface portion in the short direction of the frame. The tensile surface portion includes a longitudinally oriented layer, which can improve the tensile strength. As a result, the buckling of the entire frame can be effectively avoided, and the bending strength of the frame can be further improved.

[0018] In the above-mentioned fiber-reinforced composite frame, it is preferable that the joint between the layer constituting the compression surface portion or the tensile surface portion and the layer constituting the side portion is arranged on the same plane as the compression surface portion or the tensile surface portion.

[0019] According to this configuration, the joint between the layer constituting the compression surface portion or the tensile surface portion and the layer constituting the side surface portion is arranged on the same plane as the compression surface portion or the tensile surface portion and is located away from the corners of the frame, so that it is possible to suppress bending of the corner starting from the joint.

[0020] In the above-mentioned fiber-reinforced composite frame, it is preferable that the longitudinally oriented layers are arranged so as to avoid the corners.

[0021] According to this configuration, the longitudinal orientation layer is positioned to avoid the corners of the frame, thereby minimizing damage caused by delamination and cracks that occur at the corners, and further suppressing bending at the corners.

[0022] In the above-mentioned fiber-reinforced composite frame, the longitudinal orientation layer is preferably disposed on the inner and / or outer surface layer of the compression surface portion.

[0023] When a bending load is applied to the frame, the compressive stress is greatest in the inner and outer surface layers of the compressed surface portion, and the strain in the compressed surface portion is greatest. In the above configuration, the longitudinally oriented layer is disposed in the inner and / or outer surface layers of the compressed surface portion, so that the compressed surface portion can withstand a higher compressive stress, and the buckling strength of the compressed surface portion can be improved. At the same time, the bending rigidity can also be improved.

[0024] In the above-mentioned fiber-reinforced composite frame, it is preferable that the compression surface portion further includes a short-side orientation layer in which reinforcing fibers are oriented in the short-side direction, and that the longitudinal orientation layer is arranged on the surface side of the compression surface portion relative to the short-side orientation layer.

[0025] When a bending load is applied to the frame, the compressive stress tends to be greater closer to the surface of the compressed surface. In the above configuration, the longitudinally oriented layer is disposed closer to the surface of the compressed surface than the transversely oriented layer, so that the compressed surface can withstand a higher compressive stress and improve the buckling strength of the compressed surface. At the same time, the bending rigidity can also be improved.

[0026] In this configuration, the longitudinal orientation layer may be disposed only on the surface layer side of the compressed surface portion, or on both the surface layer side and the central layer side.

[0027] In the above-mentioned fiber-reinforced composite frame, ,before The short-side orientation layer of the compressed surface portion and the short-side orientation layer of the side surface portion are preferably disposed continuously from the compressed surface portion to the side surface portion.

[0028] According to this configuration, the short-side oriented layer is continuously arranged from the compression surface portion to the side surface portion, so that it is possible to suppress deformation that crushes the cross section in the short-side direction around the entire circumference of the frame, and it is possible to further improve the bending strength of the frame.

[0029] In the above-mentioned fiber-reinforced composite frame, the side portion further includes the longitudinal orientation layer, and the longitudinal orientation layer of the side portion is the short-side orientation layer, the 45-degree orientation layer, and the -45-degree orientation layer It is more preferable that the side wall is disposed at the center in the thickness direction of the side wall.

[0030] When a bending load is applied to the frame, the compressive and tensile stresses in the short direction, i.e., in the circumferential direction of the cross section, tend to be smaller as the side surface is closer to the center in the thickness direction. Therefore, as in the above configuration, the longitudinal orientation layer of the side surface Short-distance orientation layer, 45-degree orientation layer, and -45-degree orientation layer If the longitudinal orientation layer is disposed in the center of the side surface in the thickness direction, the effect of compressive and tensile stress in the circumferential direction of the cross section, which is detrimental to the longitudinal orientation layer, is reduced, and the longitudinal orientation layer is disposed on the surface side of the longitudinal orientation layer. Short-distance orientation layer, 45-degree orientation layer, and -45-degree orientation layer This makes it possible to suppress deformation of the side surface portion.

[0031] In the above-mentioned fiber-reinforced composite frame, it is preferable that the frame is applied to at least one selected from the group consisting of a center pillar, a bumper beam, a side sill, a hinge pillar, a front pillar, and a cross member that constitute the body of a vehicle.

[0032] According to this configuration, by applying the above frame to at least one of the center pillar, bumper beam, side sill, hinge pillar, front pillar, and cross member that constitute the body of the vehicle, when a bending load is input to the frames that constitute each of the above parts of the body during a vehicle collision, buckling of the entire frame is prevented and the frame can withstand the bending load, thereby improving the rigidity of the vehicle body. Effect of the Invention

[0033] According to the fiber-reinforced composite frame of the present invention, the occurrence of buckling of the frame can be suppressed and bending strength can be improved. [Brief description of the drawings]

[0034] [Figure 1] 1 is a schematic perspective view showing the overall configuration of a fiber-reinforced composite frame according to an embodiment of the present invention. [Diagram 2] FIG. 2 is a front view showing an end face of the fiber-reinforced composite frame of FIG. [Diagram 3] FIG. 3 is an enlarged cross-sectional view of the fiber-reinforced composite frame of FIG. 2. [Figure 4] FIG. 4 is an exploded perspective view partially showing the layered structure of the compression surface portion of FIG. 3. [Diagram 5] FIG. 4 is an exploded perspective view partially showing the layered structure of the side portion of FIG. 3. [Figure 6] FIG. 2 is an explanatory perspective view showing an example in which the fiber-reinforced composite frame of FIG. 1 is applied to components of various parts of a vehicle body. [Figure 7] FIG. 11 is an enlarged cross-sectional view of a fiber-reinforced composite frame according to a modified example of the present invention. [Figure 8] FIG. 11 is an enlarged cross-sectional view of a fiber-reinforced composite frame according to another modified example of the present invention. [Figure 9] FIG. 11 is an enlarged cross-sectional view of a fiber-reinforced composite frame according to still another modified example of the present invention. [Figure 10] FIG. 11 is an enlarged cross-sectional view of a fiber-reinforced composite frame according to still another modified example of the present invention. [Figure 11] FIG. 11 is an enlarged cross-sectional view of a fiber-reinforced composite frame according to still another modified example of the present invention. [Figure 12] FIG. 11 is an enlarged cross-sectional view of a fiber-reinforced composite frame according to still another modified example of the present invention. [Figure 13] FIG. 11 is an enlarged cross-sectional view of a fiber-reinforced composite frame according to still another modified example of the present invention. [Figure 14] FIG. 11 is an enlarged cross-sectional view of a fiber-reinforced composite frame according to still another modified example of the present invention. [Figure 15] FIG. 11 is an enlarged cross-sectional view of a fiber-reinforced composite frame according to still another modified example of the present invention. [Figure 16] FIG. 11 is an enlarged cross-sectional view of a fiber-reinforced composite frame according to still another modified example of the present invention. [Figure 17]FIG. 2 is a cross-sectional view of a frame made of a fiber-reinforced composite material having quasi-isotropy as a comparative example of the present invention. [Figure 18] FIG. 18 is an exploded perspective view partially showing the layered structure of the fiber-reinforced composite frame of FIG. 17. [Figure 19] 18 is a graph showing the load distribution when a bending load is input in the fiber-reinforced composite frame of the present embodiment, in comparison with the frame having pseudo-isotropy in FIG. 17 as a comparative example. [Figure 20] FIG. 18 is an explanatory perspective view showing the state of deformation when a bending load is input in the fiber-reinforced composite frame of the present embodiment, in comparison with the frame having pseudo-isotropy in FIG. 17 as a comparative example. [Figure 21] 21 is a cross-sectional explanatory view showing deformation of the fiber-reinforced composite frame of the present embodiment shown in FIG. 20 when a bending load is input thereto. FIG. [Figure 22] 21 is a cross-sectional explanatory view showing the state of deformation when a bending load is input to the fiber-reinforced composite frame of the comparative example of FIG. 20. [Figure 23] FIG. 2 is a perspective explanatory diagram showing, in a simplified manner, the structure of a fiber-reinforced composite frame of this embodiment, in which joints are arranged on the same plane as the compression surface or tension surface. [Figure 24] FIG. 13 is a perspective explanatory diagram showing, in a simplified form, a structure in which joints are arranged at corners in a fiber-reinforced composite frame as a comparative example. [Diagram 25] 25 is a perspective explanatory view showing that a portion near a corner of a compression surface portion in the frame of the comparative example in FIG. 24 receives a local bending load. FIG. [Figure 26] 25 is a graph showing the load distribution when a bending load is applied to the fiber-reinforced composite frame of the present embodiment, in comparison with the frame of FIG. 24 in which the joints are arranged at the corners, as a comparative example. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0035] Hereinafter, a preferred embodiment of the present invention will be described in detail with reference to the accompanying drawings.

[0036] As shown in FIGS. 1 and 2, a fiber-reinforced composite frame 1 (hereinafter referred to as frame 1) has a closed cross section 1b having a plurality of corners 5, and extends in a predetermined direction (the longitudinal direction D in FIG. 1). L The frame 1 is used as a member constituting each part of a vehicle body 21 (see FIG. 6) of a vehicle to be described later.

[0037] Specifically, the frame 1 has a basic structure in which the longitudinal direction D of the frame 1 is L The material has four surfaces extending in a axial direction, namely, a compression surface portion 2, a pair of side surface portions 3 spaced apart on both sides of the compression surface portion 2 in the width direction, and a tensile surface portion 4 spaced apart from but facing the compression surface portion 2.

[0038] The compression surface portion 2, the pair of side portions 3, and the tensile surface portion 4 are each integrally formed by stacking and molding a plurality of fiber orientation layers (i.e., the longitudinal orientation layer 11, the lateral orientation layer 12, the +45 degree orientation layer 13, and the -45 degree orientation layer 14 shown in FIG. 3). The compression surface portion 2, the pair of side portions 3, and the tensile surface portion 4 form a rectangular closed cross section 1b having four corners 5. The corners 5 may be chamfered in a straight line or an arc.

[0039] The compression surface portion 2 is in the longitudinal direction D of the frame 1. L (i.e., the longitudinal direction D L (inclined 90 degrees to the short side) D S A bending load F that bends frame 1 toward B When the input is made for frame 1, the longitudinal direction D L In other words, the compressed surface portion 2 is the inner curved surface of the bent frame 1.

[0040] Here, the bending load F B is the longitudinal direction D of frame 1 L Short direction D perpendicular to SFor example, when a vehicle body 21 (see FIG. 6) of a vehicle collides with an external obstacle (such as an automobile or a roadside object), as shown in FIG. 1, the frame 1 is supported at both ends (for example, in the simplified model of FIG. 1, the frame 1 is supported at both ends by a pair of fulcrums S), and the compression surface portion 2 is subjected to a compression load (collision load) F. P in the short direction D S (i.e., the normal direction of the compression surface portion 2 in FIG. 1). In this case, the bending load F P is received by the compression surface portion 2 of the frame 1.

[0041] Or, bending load F B is the longitudinal direction D of frame 1 L From the end 1a in the longitudinal direction D L It is also assumed that a bending load occurs when a compressive load (collision load) is applied toward the cross member 26 (for example, a bending load applied to the cross member 26 when an obstacle collides with the side of the vehicle body 21 in FIG. 6). In this case, the compressive load is applied to the end 1a of the frame 1.

[0042] Each of the pair of side portions 3 is formed in a width direction D from a pair of corner portions 5 adjacent to the compression surface portion 2. S (specifically, the bending load F B or compressive load F P The side surface 3 is a portion that constitutes the frame 1 when the frame 1 is subjected to a bending load F B When subjected to a force, compressive stress is generated in an area closer to the compression surface portion 2 than the neutral axis N in Fig. 1, and tensile stress is generated in an area closer to the tensile surface portion 4 than the neutral axis N. Corners 5 are formed by each of the pair of side portions 3 and the compression surface portion 2.

[0043] The tensile surface portion 4 is spaced apart from the compression surface portion 2 in the longitudinal direction D L and bending load F B When is entered for frame 1, the longitudinal direction D LThe tensile stress σ2 occurs along the tensile surface 4. That is, the tensile surface portion 4 becomes the outer curved surface of the bent frame 1. The tensile surface portion 4 and each of the pair of side surface portions 3 form corner portions 5.

[0044] As shown in FIGS. 3 and 4, the compression surface portion 2 of the present embodiment is L Specifically, the compression surface portion 2 shown in Figs. 3 and 4 includes two layers of the longitudinal orientation layer 11, four layers of the lateral orientation layer 12, and two layers of the longitudinal orientation layer 11 arranged in the thickness direction D of the cross section of the frame 1. T The laminated structure of the compression surface portion 2 is formed in a thickness direction D T The structure is symmetrical in

[0045] Specifically, as shown in FIG. 4, the longitudinal orientation layer 11 is formed by a substrate 11b and a frame 1 in the longitudinal direction D. L The same direction D1 (i.e., the longitudinal direction D L The reinforcing fibers 11a are oriented at an inclination angle of 0 degrees with respect to the surface.

[0046] The base material 11b (12b, 13b, 14b) refers to a sheet-like base material made of reinforcing fibers 11a (12a, 13a, 14a) and resin used in autoclave molding or press molding, or a base material with reinforcing fibers 11a temporarily attached used in RTM molding. The base material 11b is made of, for example, a resin material having excellent heat resistance, strength, and processability, such as a resin such as epoxy resin. The reinforcing fibers 11a are made of a lightweight and high-strength fiber material, such as carbon fiber, glass fiber, aramid fiber, cellulose fiber, steel fiber, or the like. In particular, carbon fiber is preferable because it is both lightweight and strong.

[0047] Specifically, as shown in FIG. 4, the transverse direction orientation layer 12 is formed by a substrate 12b and a frame 1 in the transverse direction D. S , i.e., the longitudinal direction D Land reinforcing fibers 12a oriented in a direction D2 (inclination angle 90 degrees) perpendicular to the lateral direction. The base material 12b and reinforcing fibers 12a of the lateral direction orientation layer 12 are made of the same material as the base material 11b and reinforcing fibers 11a of the longitudinal direction orientation layer 11, but other materials may also be used.

[0048] The surface layer of the side portion 3 shown in FIG. 3 and FIG. 5 is L The "surface layer" of the side portion 3 here means the surface layer on the inside and outside of the cross section of the frame 1.

[0049] The anisotropic orientation layer is L Therefore, the layer having the reinforcing fibers oriented in a different direction from the short direction D S A layer 12 in which reinforcing fibers are oriented in the transverse direction or in the longitudinal direction D L Alternatively, the layer may be a 45-degree oriented layer in which reinforcing fibers are oriented in a direction inclined at 45 degrees to the center (more specifically, a +45-degree oriented layer 13 and a -45-degree oriented layer 14 described later).

[0050] As shown in FIG. 5, the transverse direction orientation layer 12 is formed by bonding the substrate 12b and the frame 1 in the transverse direction D in the same manner as described above. S and reinforcing fibers 12a oriented in a direction perpendicular to the surface of the substrate 12.

[0051] The 45-degree oriented layer is aligned in the longitudinal direction D L As shown in FIG. 5, the layer in which the reinforcing fibers are oriented in a direction inclined at 45 degrees to the longitudinal direction D L The +45 degree orientation layer 13 is inclined at 45 degrees to the longitudinal direction D L The layer 14 may be either a layer tilted at -45 degrees or a layer tilted at -45 degrees.

[0052] For example, in the +45 degree orientation layer 13, the reinforcing fibers 13a are aligned in the longitudinal direction D L The -45 degree orientation layer 14 is a layer in which the reinforcing fibers 14a are oriented in a direction rotated 45 degrees counterclockwise in the in-plane direction of the orientation layer 13 based on the longitudinal direction D.L It is a layer oriented in a direction rotated 45 degrees clockwise (−45 degrees if the counterclockwise direction is the positive direction) in the in-plane direction of the orientation layer 14 with respect to the reference direction.

[0053] Specifically, the side portion 3 shown in FIG. 3 and FIG. 5 includes two layers of lateral direction orientation layers 12, a +45 degree orientation layer 13, two layers of -45 degree orientation layers 14, a +45 degree orientation layer 13, and two layers of lateral direction orientation layers 12 in the thickness direction D of the cross section of the frame 1. T The laminated structure of the side portion 3 is configured in a thickness direction D T The structure is symmetrical in

[0054] Specifically, the +45-degree orientation layer 13 is, as shown in FIG. 5, a substrate 13b and a layer L 5, the -45 degree oriented layer 14 is composed of a base material 14b and a reinforcing fiber 13a oriented in a direction D3 inclined at +45 degrees with respect to the longitudinal direction D. L and reinforcing fibers 14a oriented in a direction D4 inclined at -45 degrees with respect to the longitudinal direction. The base materials 13b, 14b and reinforcing fibers 13a, 14a are also made of the same materials as the base material 11b and reinforcing fibers 11a of the longitudinal orientation layer 11, but other materials may also be used.

[0055] The tensile surface portion 4 shown in Fig. 3 has a longitudinal orientation layer 11, similar to the compression surface portion 2. Specifically, the tensile surface portion 4 shown in Fig. 3 has the same layered structure as the compression surface portion 2, that is, two longitudinal orientation layers 11, four lateral orientation layers 12, and two longitudinal orientation layers 11 arranged in the thickness direction D of the cross section of the frame 1. T Therefore, the laminated structure of the tensile surface portion 4 is also laminated in the thickness direction D in the same manner as the laminated structure of the compression surface portion 2. T The structure is symmetrical in

[0056] As shown in Fig. 3, in this embodiment, the joint 6 between the layer constituting the compression surface portion 2 or the tension surface portion 4 and the layer constituting the side surface portion 3 is disposed on the same plane as the compression surface portion 2 or the tension surface portion 4. Specifically, the layers constituting the compression surface portion 2 or the tension surface portion 4 are four longitudinally oriented layers 11 and four laterally oriented layers 12, as shown in Fig. 3. The layers constituting the side surface portion 3 are four laterally oriented layers 12, two +45 degree oriented layers 13, and two -45 degree oriented layers 14.

[0057] The "joint 6" referred to here is a portion where adjacent different layers are joined together. The joint 6 includes various types of joints, such as a portion where two adjacent layers are joined in a partially laminated state, or a portion where the ends of two adjacent layers are joined together.

[0058] As shown in FIG. 3, the longitudinal orientation layers 11 on the compression surface portion 2 and the tensile surface portion 4 are disposed at positions that avoid the corners 5.

[0059] Moreover, the longitudinal orientation layer 11 is arranged on the surface layer on the inner side (i.e., the inner surface side of the closed cross section 1b of the frame 1) and / or the outer side (i.e., the outer surface side of the frame 1) of each of the compression surface portion 2 and the tensile surface portion 4.

[0060] Furthermore, as shown in FIG. Pressure The short-side orientation layer 12 of the contracted surface portion 2 and the short-side orientation layer 12 of the side surface portion 3 are continuously disposed from the compressed surface portion 2 to the side surface portion 3. Specifically, the short-side orientation layer 12 is disposed over the entire periphery of the frame 1 in the short-side direction Ds (i.e., the compressed surface portion 2, the pair of side surface portions 3, and the tensile surface portion 4). In the case of such a short-side orientation layer 12 disposed over the entire periphery of the frame 1, the breaks (or the joints between the edges) of the short-side orientation layer 12 will be broken by the compressive load (collision load) F in FIG. P It is preferable that the tension surface portion 4 is provided thereon, which is less susceptible to the influence of the above.

[0061] The frame 1 of this embodiment configured as described above is applied to various members constituting a vehicle body 21 that require high bending strength during a vehicle collision, for example, at least one selected from the group consisting of a center pillar 20, a bumper beam 22, a side sill 23, a hinge pillar 24, a front pillar 25, and a cross member 26, as shown in FIG. 6.

[0062] When the frame of the above embodiment is applied to the center pillar 20, the bumper beam 22, the side sill 23, the hinge pillar 24, and the front pillar 25 among these groups, the compression surface portion 2 (i.e., the surface to which the collision load is input) may be arranged on the surface facing the outside of the vehicle body 21. Also, for the cross member 26, the compression surface portion 2 may be arranged on the surface facing upward or downward.

[0063] Here, the center pillar 20 is a member extending in the vertical direction between the front door and the rear door at the side end of the vehicle body 21. The bumper beam 22 is a member extending in the width direction of the vehicle body 21 at the front end of the vehicle body 21 and constituting a bumper. The side sill 23 is a member extending in the front-rear direction of the vehicle body 21 at the lower side end of the vehicle body 21. The hinge pillar 24 is a member extending in the vertical direction at the front side of the side end of the vehicle body 21 and to which the front door of the vehicle body 21 is hinged. The front pillar 25 is a member extending in a substantially arc shape upward and backward (diagonally backward) on both sides of the windshield at the front side of the vehicle body 21. The cross member 26 is a member extending in the width direction of the vehicle body 21 at the floor part of the vehicle body 21.

[0064] (Features of this embodiment) (1) The frame 1 of this embodiment is a frame 1 having a closed cross section 1b with a plurality of corners 5 and manufactured from a fiber-reinforced composite material extending in a predetermined direction. As shown in FIG. 1, the frame 1 is L Short direction D perpendicular to S A bending load F that bends frame 1 toward B When the input is made for frame 1, the longitudinal direction DL The compression surface 2 along which the compressive stress σ1 occurs and the corner 5 adjacent to the compression surface 2 in the short direction D S and a side portion 3 extending therefrom.

[0065] As shown in FIGS. 3 to 5, the compression surface portion 2 is L The surface layer of the side portion 3 (i.e., the inner and outer surface layers of the frame 1) is provided with a longitudinal orientation layer 11 in which reinforcing fibers are oriented in the longitudinal direction D. L The laminated sheet is constituted by a short-side orientation layer 12 as a different-direction orientation layer in which reinforcing fibers are oriented in a direction different from that of the short-side orientation layer 12.

[0066] In this configuration, the frame 1 is L Bending load F perpendicular to B When the input is made, the compression surface portion 2 is in the longitudinal direction D of the frame 1. L The compressive stress σ1 occurs along the longitudinal direction D of the frame 1. L Since the compression surface portion 2 has the longitudinal orientation layer 11 along the longitudinal direction D, the compression surface portion 2 can withstand a high compressive stress σ1, and the buckling strength of the compression surface portion 2 can be improved. At the same time, the bending rigidity can also be improved. L (for example, the short side direction D of the frame 1 at the side portion 3) S or the longitudinal direction D of frame 1 L The frame 1 is configured with a transversely oriented layer 12 as a different-direction oriented layer in which reinforcing fibers are oriented in a different direction (a diagonal direction inclined with respect to the lateral direction). This enables the side portion 3 to withstand high shear stress and bending stress, and makes it possible to suppress deformation of the side portion 3 (especially buckling deformation). With this configuration, even if delamination occurs at the corner portion 5 of the frame 1, it is possible to suppress the progression of cracks to the compression surface portion 2 and the side portion 3, and it is possible to increase the buckling strength of the frame 1. As a result, it is possible to prevent buckling of the entire frame 1 and improve the bending strength of the frame 1.

[0067] (2) In the frame 1 of this embodiment, the anisotropic orientation layer constituting the surface layer of the side surface portion 3 is S Since the reinforcing fibers are oriented in the short-side direction D S The rigidity of the side portion 3 in the short direction D S It is possible to improve the bending rigidity against a load in the direction of crushing.

[0068] (3) In the frame 1 of this embodiment, the anisotropic orientation layer constituting the surface layer of the side surface portion 3 is L Alternatively, the side wall 3 may have a 45-degree oriented layer (specifically, a +45-degree oriented layer 13 and a -45-degree oriented layer 14) in which reinforcing fibers are oriented in a direction inclined at 45 degrees to the side wall 3. In this case, the shear rigidity of the side wall 3 can be improved.

[0069] (4) As shown in FIG. 3, the frame 1 of this embodiment is arranged in a longitudinal direction D at a position separated from the compression surface portion 2. L and bending load F B When is entered for frame 1, the longitudinal direction D L The tensile surface portion 4 further comprises a longitudinal orientation layer 11 along which a tensile stress σ2 occurs.

[0070] According to this configuration, the bending load F B When the input is made, the compression surface 2 is compressed in the short direction D of the frame 1. S In the tensile surface portion 4 spaced apart from each other, the longitudinal direction D of the frame 1 L A tensile stress σ2 occurs along the longitudinal direction. The tensile surface portion 4 has a longitudinal orientation layer 11, which can improve the tensile strength. As a result, the buckling of the entire frame 1 can be effectively avoided, and the bending strength of the frame 1 can be further improved.

[0071] (5) In the frame 1 of this embodiment, as shown in Figure 3, the joint 6 between the layer constituting the compression surface portion 2 or the tensile surface portion 4 and the layer constituting the side portion 3 is arranged on the same plane as the compression surface portion 2 or the tensile surface portion 4.

[0072] According to this configuration, the joint 6 between the layer constituting the compression surface portion 2 or the tensile surface portion 4 and the layer constituting the side portion 3 is arranged on the same plane as the compression surface portion 2 or the tensile surface portion 4, and is located away from the corner 5 of the frame 1, so that bending of the corner 5 starting from the joint 6 can be suppressed.

[0073] (6) 3, in the frame 1 of this embodiment, the longitudinal orientation layer 11 is disposed so as to avoid the corners 5. This makes it possible to minimize damage caused by delamination and cracks occurring at the corners 5, and further suppress bending of the corners 5.

[0074] (7) In the frame 1 of this embodiment, as shown in Fig. 3, the longitudinal orientation layer 11 is disposed on the inner and / or outer surface layer of the compression surface portion 2. In this embodiment, the longitudinal orientation layer 11 is disposed on the surface layer of each of the compression surface portion 2 and the tensile surface portion 4.

[0075] Bending load F on frame 1 B is input, the compressive stress σ1 becomes the largest in the inner and outer surface layers of the compressed surface portion 2, and the strain in the compressed surface portion 2 becomes the largest. Therefore, in the above-mentioned configuration, by disposing the longitudinal orientation layer 11 in the inner and / or outer surface layer of the compressed surface portion 2, the compressed surface portion 2 can withstand a higher compressive stress σ1, and the buckling strength of the compressed surface portion 2 can be improved. At the same time, the bending rigidity can also be improved.

[0076] (8) In the frame 1 of this embodiment, as shown in Fig. 3, the short-side direction orientation layer 12 of the compressed surface portion 2 and the short-side direction orientation layer 12 of the side surface portion 3 are continuously disposed from the compressed surface portion 2 to the side surface portion 3. Therefore, the cross section of the frame 1 is aligned in the short-side direction D S Therefore, it is possible to suppress deformation such as crushing the frame 1, and the bending strength of the frame 1 can be further improved.

[0077] (9) The frame 1 of this embodiment is applied to at least one selected from the group consisting of a center pillar 20, a bumper beam 22, a side sill 23, a hinge pillar 24, a front pillar 25, and a cross member 26 that constitute a vehicle body 21 of a vehicle. As a result, in the event of a vehicle collision, a bending load F is applied to the frame 1 that constitutes each of the above-mentioned parts of the vehicle body 21. B When the input is made, the buckling of the entire frame 1 is avoided and the frame 1 is supported by the bending load F B This makes it possible to improve the rigidity of the vehicle body 21.

[0078] (10) As shown in FIGS. 1 to 5, in the frame 1 of this embodiment, the compression surface portion 2 has not only the longitudinal orientation layer 11 but also the transverse orientation layer D S The compression surface portion 2 further includes a lateral orientation layer 12 in which reinforcing fibers are oriented in the lateral direction. The longitudinal orientation layer 11 is disposed on the surface layer side of the compression surface portion 2 relative to the lateral orientation layer 12. In this configuration, the longitudinal orientation layer 11 may be disposed only on the surface layer side of the compression surface portion 2, or on both the surface layer side and the central layer side.

[0079] Bending load F on frame 1 B When a force is input, the compressive stress σ1 tends to be larger closer to the surface layer of the compressed surface portion 2. In the configuration of the frame 1 of this embodiment, the longitudinal orientation layer 11 is disposed closer to the surface layer of the compressed surface portion 2 than the lateral orientation layer 12, so that the compressed surface portion 2 can withstand a higher compressive stress σ1, and the buckling strength of the compressed surface portion 2 can be improved. At the same time, the bending rigidity can also be improved.

[0080] Example 1 Next, the bending strength of the frame 1 of the present embodiment shown in Figs. 1 to 5 will be described in comparison with a comparative example.

[0081] The frame 1 of this embodiment has a square cross section with sides of 50 mm, and has arc-shaped chamfered portions with a radius of 10 mm at the corners 5. The thickness of each face of the frame 1 is 3.4 mm.

[0082] When examining the bending strength, the frame 1 is supported at both ends by two supports S (300 mm apart) as shown in Figure 1 based on the procedure of a general bending test. L The indenter was placed on the midpoint C of the frame 1 and displaced downward, bending the frame 1. As a result, the relationship between the downward displacement X of the indenter and the bending load P of the frame 1 (i.e., the reaction force that the indenter receives from the frame 1) was investigated, as shown by curve I in the graph of Figure 19.

[0083] On the other hand, as a comparative example, a frame 51 made of a fiber-reinforced composite material having quasi-isotropy (hereinafter referred to as frame 51) shown in Figs. 17 and 18 is prepared.

[0084] Frame 51 of the comparative example is a frame that constitutes a closed cross section 51b having a plurality of corners 55, and like frame 1 described above, is provided with a compression surface portion 52, a pair of side surface portions 53, and a tension surface portion .

[0085] However, each surface portion 52-54 of Comparative Example 51 has the same laminated structure. That is, each surface portion 52-54 is formed by laminating a plurality of longitudinal orientation layers 11, lateral orientation layers 12, +45 degree orientation layers 13, and -45 degree orientation layers 14 in approximately equal proportions so as to have pseudo-isotropy. Furthermore, these longitudinal orientation layers 11, lateral orientation layers 12, +45 degree orientation layers 13, and -45 degree orientation layers 14 are continuously disposed around the entire circumference of the frame 51 via the corners 55. Therefore, each surface portion 52-54 has the same laminated structure.

[0086] The bending strength of comparative frame 51 having pseudo-isotropy shown in FIGS. 17 and 18 was also examined in the same manner as for frame 1, and the results are shown as curve II in the graph of FIG.

[0087] In the graph of FIG. 19, it can be seen that the curve I showing the bending load P of the frame 1 of this embodiment has a maximum load that is 32% higher than the curve II showing the bending load P of the frame 51 of the comparative example. This difference in bending load is because the comparative frame 51 having pseudo-isotropy buckles and has low bending strength, whereas the frame 1 of this embodiment avoids buckling and improves bending strength. That is, in the frame 1 of this embodiment, as described above, the longitudinal orientation layer 11 arranged in large amounts on the compression surface portion 2 shown in FIG. 3 and the lateral orientation layer 12 arranged on the surface layer portion of the side surface portion 3 suppress the progression of cracks from delamination occurring at the corner portion 5 to the compression surface portion 2 and the side surface portion 3, thereby preventing buckling of the frame 1.

[0088] 20 shows the distribution of displacements of each part when the frame 1 of this embodiment and the frame 51 of the comparative example are bent. In FIG. 20, the magnitude of the displacement is indicated by the brightness of each part. For each of the frames 1 and 51, a compressive load F is applied to the midpoint between the two supports S. P When the load is applied, frame 1 of the present embodiment does not buckle, and therefore the amount of displacement on each surface is small (there are fewer dark areas of frame 1 in FIG. 20), whereas frame 51 of the comparative example buckles, and therefore the amount of displacement on each surface (especially the side surfaces) is large (there are more dark areas of frame 51 in FIG. 20, and the darkness is deeper).

[0089] As shown in Fig. 20 above, when frame 1 of this embodiment and frame 51 of the comparative example are bent, it can be seen that the cross-sectional shape of frame 1 of this embodiment shown in Fig. 21 has small out-of-plane deformation (i.e., the change in the distance between the two corners 5 is small), whereas the cross-sectional shape of frame 51 of the comparative example shown in Fig. 22 has large out-of-plane deformation (i.e., the change in the distance between the two corners 55 is large). Comparing Figs. 21 and 22 shows that frame 1 of this embodiment maintains its cross-sectional shape without buckling and has improved bending strength compared to frame 51 of the comparative example.

[0090] Example 2 23, in frame 1 of this embodiment, joint 6 between the layer constituting compression surface portion 2 or tensile surface portion 4 and the layer constituting side surface portion 3 is located at a position that avoids corner portion 5, i.e., on the same plane as compression surface portion 2 or tensile surface portion 4. As in Example 1 above, the relationship between the downward displacement X of the indenter and the bending load P of frame 1 (i.e., the reaction force that the indenter receives from frame 1) was investigated for frame 1 of this embodiment, as shown by curve III in the graph of FIG.

[0091] 24 and 25 is prepared as a comparative example. In the comparative frame 60, the joints 6 between the layer constituting the compression surface portion 2 or the tensile surface portion 4 and the layer constituting the side surface portion 3 are disposed at the corners 5.

[0092] The bending strength of comparative frame 60 shown in FIGS. 24 and 25 was also examined in the same manner as for frame 1, and the results are shown as curve IV in the graph of FIG.

[0093] In the graph of FIG. 26, curve III showing the bending load P of frame 1 of this embodiment is improved in the early stage of displacement X (10 to 11 mm or less) compared to curve IV showing the bending load P of frame 60 of the comparative example in which joint 6 is arranged at corner 5, and it can be seen that frame 1 of this embodiment has greater absorbed energy in the early stage when a bending load is input (for example, immediately after a vehicle collision).

[0094] The difference in the bending load is due to the fact that the frame 60 of the comparative example shown in FIGS. 24 and 25 has a configuration in which the longitudinal orientation layer 11 (see FIGS. 3 and 4) included in the compression surface portion 2 extends to the corner portion 5, and therefore the longitudinal orientation layer 11 included in the compression surface portion 2 is more resistant to the compression load F in the vicinity of the corner portion 5. P and different local bending load F D This is because, in a conventional frame 1, bending of the corners 5 originating from the joints 6 occurs, lowering the bending strength, whereas in the frame 1 of this embodiment, bending of the corners 5 is avoided and bending strength is improved. That is, in the frame 1 of this embodiment, as described above, the joints 6 between the layer constituting the compression surface portion 2 or the tensile surface portion 4 and the layer constituting the side surface portion 3 are disposed on the same plane as the compression surface portion 2 or the tensile surface portion 4, and are located away from the corners 5 of the frame 1, so that bending of the corners 5 originating from the joints 6 can be suppressed.

[0095] (Modification) (A) In the frame 1 of the above embodiment, as shown in Figures 3 and 4, the compression surface portion 2 is configured in such a manner that two longitudinal orientation layers 11, four short-side orientation layers 12, and two longitudinal orientation layers 11 are stacked together, i.e., the configuration does not have a +45 degree orientation layer 13 and a -45 degree orientation layer 14, but the present invention is not limited to this.

[0096] That is, as in the frame 1 shown in Fig. 7 as a modified example of the present invention, the compression surface portion 2 may have a +45 degree orientation layer 13 and a -45 degree orientation layer 14. For example, the compression surface portion 2 of the frame 1 shown in Fig. 7 may have a laminated configuration of two layers of longitudinal orientation layer 11, lateral orientation layer 12, +45 degree orientation layer 13, two layers of -45 degree orientation layer 14, +45 degree orientation layer 13, lateral orientation layer 12, and two layers of longitudinal orientation layer 11.

[0097] In the frame 1 shown in Figure 7, a short-side orientation layer 12, a +45 degree orientation layer 13, two layers of -45 degree orientation layers 14, a +45 degree orientation layer 13, and a short-side orientation layer 12 are arranged around the entire circumference of the frame 1, and two layers of longitudinal orientation layers 11 are arranged on the inner and outer surface sides of the compression surface portion 2 and the tensile surface portion 4.

[0098] As described above, in the frame 1 shown in Fig. 7, even if the compressed surface portion 2 has a configuration including a +45 degree oriented layer 13 and a -45 degree oriented layer 14, two longitudinally oriented layers 11 are arranged on the inner and outer surface layers of the compressed surface portion 2. This enables the compressed surface portion 2 to withstand a higher compressive stress σ1, and it is possible to improve the buckling strength of the compressed surface portion 2. At the same time, it is also possible to improve the bending rigidity.

[0099] The frame 1 of the modified example shown in FIG. 7 can also achieve the same advantageous effects as those of the features (1) to (10) of the above embodiment.

[0100] (B) In the frame 1 of the above embodiment, as shown in Figs. 3 and 5, the -45 degree orientation layer 14 is disposed in the center in the thickness direction of the side surface portion 3, but the present invention is not limited to this.

[0101] That is, like the modified frame 1 shown in Figure 8 (and Figures 10-11 and Figures 14-16), the side portion 3 may further include a longitudinal orientation layer 11, and the longitudinal orientation layer 11 of the side portion 3 may be arranged more centrally in the thickness direction of the side portion 3 than the anisotropic orientation layers (in this embodiment, the short-side orientation layer 12, the +45 degree orientation layer 13, and the -45 degree orientation layer 14).

[0102] Bending load F on frame 1 B When the input is made, the closer to the center position in the thickness direction of the side portion 3, the larger the width in the short direction D S , that is, the compressive and tensile stresses in the circumferential direction of the cross section tend to be smaller. Therefore, as in the configuration shown in Fig. 8 (and Figs. 10-11, 14-16) above, if the longitudinal orientation layer 11 of the side portion 3 is disposed closer to the center in the thickness direction of the side portion 3 than the anisotropic orientation layer, it is possible to reduce the influence of the compressive and tensile stresses in the circumferential direction of the cross section, which is detrimental to the shear stress on the longitudinal orientation layer 11, while suppressing the deformation of the side portion 3 by the anisotropic orientation layer located on the surface side of the longitudinal orientation layer 11.

[0103] (C) The frame 1 shown in Fig. 8 is configured by increasing the longitudinal orientation layer 11 on the surface side of the compression surface portion 2 and the tensile surface portion 4 using a pseudo-isotropic frame as a base, and further increasing the transverse orientation layer 12 on the side surface portion 3. With this configuration as well, it is possible to achieve the same effects as the features (1) to (10) of the above embodiment.

[0104] (D) The modified frame 1 shown in Figure 9 is constructed by adding longitudinal orientation layers 11 and transverse orientation layers 12 to the surface layers of the compression surface portion 2 and the tensile surface portion 4.

[0105] In the frame 1 shown in Figure 9, a short-side orientation layer 12, a longitudinal orientation layer 11, two layers of short-side orientation layers 12, a longitudinal orientation layer 11, and a short-side orientation layer 12 are arranged around the entire circumference of the frame 1, and two layers of longitudinal orientation layers 11 are arranged on the inner and outer surface sides of the compression surface portion 2 and the tensile surface portion 4.

[0106] This configuration also makes it possible to achieve the same advantageous effects as those of the features (1) to (2), (4) to (5), and (7) to (10) of the above-described embodiment.

[0107] (E) The frame 1 of the modified example shown in Fig. 10 is configured by dividing the orientation ratio of each of the orientation layers 11-14 equally and optimizing the arrangement of each of the orientation layers 11-14 in the plate thickness direction. In the frame 1 shown in Fig. 10, a longitudinal orientation layer 11 is arranged on the inner and outer surface layers of the compression surface portion 2 and the tensile surface portion 4, and a transverse orientation layer 12 is arranged on the inner and outer surface layers of the side surface portion 3. With this configuration, it is possible to achieve the same effects as the features (1)-(5) and (7)-(10) of the above embodiment.

[0108] (F) The frame 1 of the modified example shown in Fig. 11 is configured by disposing a longitudinal orientation layer 11 on the surface layer side of the compression surface portion 2 and the tensile surface portion 4, and disposing a transverse orientation layer 12 on the surface layer side of the side surface portion 3, based on a pseudo-isotropic frame similar to the frame 1 of Fig. 8. With this configuration as well, it is possible to achieve the same effects as the features (1) to (5) and (7) to (10) of the above embodiment.

[0109] (G) As described above, in the frame 1 of the embodiment shown in Figures 1 to 5 and the frame 1 shown in Figures 7 to 11, a longitudinal orientation layer 11 is arranged on the surface layer portions of the compression surface portion 2 and the tensile surface portion 4, but the present invention is not limited to this.

[0110] That is, in the present invention, it is sufficient that the compressed surface portion 2 is provided with a longitudinal orientation layer 11 and the surface portion of the side surface portion 3 is provided with a lateral orientation layer, and as in the modified frame 1 shown in Figures 12 to 16, a layer other than the longitudinal orientation layer 11, for example a +45 degree orientation layer 13, may be arranged on the surface side of the longitudinal orientation layer 11 of the compressed surface portion 2 and the tensile surface portion 4. The frames 1 shown in Figures 12 to 16 can also achieve the same effects as the features (1) to (6) and (8) to (10) of the above embodiment (note that in the case of Figures 14 to 16, (6) is excluded).

[0111] In addition, the modified frame 1 shown in Figure 12 has a configuration in which a +45 degree orientation layer 13 is added to the surface layers of the compression surface portion 2 and the tensile surface portion 4 of the frame 1 of the present embodiment shown in Figure 3, and the +45 degree orientation layer 13 of the side portion 3 is moved to the surface portion of the side portion 3.

[0112] The modified frame 1 shown in Figure 13 has a configuration in which the +45 degree orientation layers 13 of the compression surface portion 2, side surface portion 3, and tensile surface portion 4 of the modified frame 1 shown in Figure 7 have been moved to the surface portions of the compression surface portion 2, side surface portion 3, and tensile surface portion 4, respectively.

[0113] The modified frame 1 shown in Figure 14 has a configuration in which the +45 degree orientation layers 13 of the compression surface portion 2, side surface portion 3, and tensile surface portion 4 of the modified frame 1 shown in Figure 8 have been moved to the surface portions of the compression surface portion 2, side surface portion 3, and tensile surface portion 4, respectively.

[0114] The modified frame 1 shown in Figure 15 has a configuration in which the +45 degree orientation layers 13 of the compression surface portion 2, side surface portion 3, and tensile surface portion 4 of the modified frame 1 shown in Figure 10 have been moved to the surface portions of the compression surface portion 2, side surface portion 3, and tensile surface portion 4, respectively.

[0115] The modified frame 1 shown in Figure 16 has a configuration in which the +45 degree orientation layers 13 of the compression surface portion 2, side surface portion 3, and tensile surface portion 4 of the modified frame 1 shown in Figure 11 have been moved to the surface portions of the compression surface portion 2, side surface portion 3, and tensile surface portion 4, respectively.

[0116] (H) In addition, with regard to the orientation angles of the reinforcing fibers shown in the above embodiments and modified examples, for example, "0 degrees," "90 degrees," "45 degrees," and "-45 degrees," the effects of the present invention can be achieved as long as they are within a range of ±15 degrees of these angles. [Explanation of symbols]

[0117] 1 Fiber-reinforced composite frame 2 Compression surface 3 Side part 4 Tensile surface 5 Corner 6 Joint 11 Longitudinal orientation layer 12 Short-side orientation layer 13 +45 degree orientation layer 14 -45 degree orientation layer 11a~14a Reinforced Fiber 20 Center pillar 21 Body 22 Bumper beam 23 Side sill 24 Hinge pillar 25 Front pillar 26 Cross member

Claims

1. A fiber-reinforced composite frame having a closed cross section with a plurality of corners and extending in a predetermined direction, The frame is a compression surface portion in which a compressive stress is generated along a short side direction perpendicular to a long side direction of the frame when a bending load that bends the frame in the short side direction perpendicular to the long side direction of the frame is input to the frame; a side surface portion extending in the short direction from the corner portion adjacent to the compression surface portion; Equipped with The compression surface portion includes a longitudinal orientation layer in which reinforcing fibers are oriented in the longitudinal direction, The inner and outer surface layers of the side surface portion are composed of short-side orientation layers in which reinforcing fibers are oriented in the short-side direction, The side portion includes a 45 degree oriented layer in which reinforcing fibers are oriented in a direction inclined at 45 degrees to the longitudinal direction, and a -45 degree oriented layer in which reinforcing fibers are oriented in a direction inclined at -45 degrees to the longitudinal direction, The 45 degree orientation layer and the −45 degree orientation layer are disposed at a central portion in the thickness direction of the side surface portion relative to the short side orientation layer. A fiber-reinforced composite frame.

2. 2. The fiber-reinforced composite frame according to claim 1, The longitudinal orientation layers are disposed on the inner and outer surface layers of the compression surface portion, The compression surface portion further includes a short-side orientation layer in which reinforcing fibers are oriented in the short-side direction, The short-side orientation layer is disposed at a central portion in the thickness direction of the compression surface portion relative to the long-side orientation layer. A fiber-reinforced composite frame.

3. 3. The fiber-reinforced composite frame according to claim 1, The frame further includes a tension surface portion extending in the longitudinal direction at a position spaced apart from the compression surface portion, and in which a tensile stress is generated along the longitudinal direction when the bending load is input to the frame, The tensile surface portion comprises the longitudinal orientation layer. A fiber-reinforced composite frame.

4. 4. The fiber-reinforced composite frame according to claim 3, a joint between a layer constituting the compression surface portion or the tensile surface portion and a layer constituting the side surface portion is disposed on the same plane as the compression surface portion or the tensile surface portion; A fiber-reinforced composite frame.

5. The fiber-reinforced composite frame according to any one of claims 1 to 4, The longitudinal orientation layer is arranged to avoid the corner portion. A fiber-reinforced composite frame.

6. The fiber-reinforced composite frame according to any one of claims 1 to 5, The longitudinal orientation layer is disposed on the inner and / or outer surface layer of the compression surface portion. A fiber-reinforced composite frame.

7. 2. The fiber-reinforced composite frame according to claim 1, The compression surface portion further includes a short-side orientation layer in which reinforcing fibers are oriented in the short-side direction, The longitudinal orientation layer is disposed on the surface side of the compressed surface portion relative to the lateral orientation layer. A fiber-reinforced composite frame.

8. 8. The fiber-reinforced composite frame according to claim 7, The short-side orientation layer of the compression surface portion and the short-side orientation layer of the side surface portion are continuously arranged from the compression surface portion to the side surface portion. A fiber-reinforced composite frame.

9. The fiber-reinforced composite frame according to any one of claims 1 to 8, The side portion further comprises the longitudinal orientation layer, The longitudinal orientation layer of the side surface portion is disposed at a central portion in the thickness direction of the side surface portion relative to the lateral orientation layer, the 45 degree orientation layer, and the -45 degree orientation layer. A fiber-reinforced composite frame.

10. The fiber-reinforced composite frame according to any one of claims 1 to 9, The frame is applied to at least one selected from the group consisting of a center pillar, a bumper beam, a side sill, a hinge pillar, a front pillar, and a cross member that constitute a body of a vehicle. A fiber-reinforced composite frame.

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