Vehicle body floor structure

Abstract

In the present invention, load bearing is improved and a load transfer path is ensured when forming a vehicle body floor structure using a fiber-reinforced resin composite material. This vehicle body floor structure composed of a fiber-reinforced resin composite material comprises: a panel base material that is composed of a fiber-reinforced resin composite material; and a continuous fiber-reinforced resin band that is disposed with a first connection part and a second connection part respectively joined to other structural materials of the panel base material as the two ends thereof, and includes continuous fibers sewn on the panel base material.

Description

Body floor structure

[0001] The technology of the present disclosure relates to an automobile body floor structure using a fiber-reinforced resin composite material.

[0002] In recent years, with the aim of reducing the weight of automobile bodies such as passenger cars, progress has been made in manufacturing vehicle body structural materials using fiber-reinforced resins, typified by carbon fiber reinforced plastic (hereinafter referred to as CFRP). Structural materials made of fiber-reinforced resin have high rigidity and exhibit high strength, particularly against compressive stress or tensile stress acting in the fiber orientation direction. For example, Patent Document 1 discloses a vehicle panel structure in which a portion of the vehicle body floor is constructed using reinforcing fibers. Specifically, the vehicle panel structure described in Patent Document 1 has a configuration in which a fiber-reinforced resin panel is fixed to a floor tunnel, cross member, and panel support portion made of steel plate.

[0003] Japanese Patent Application Laid-Open No. 2017-165173

[0004] The vehicle panel structure described in Patent Document 1 uses fiber-reinforced resin only for the floor panel portion, and there is still room for weight reduction. On the other hand, the vehicle body floor is joined to multiple other structural members such as toe boards and side sills, and requires strength or rigidity sufficient to withstand input loads in all types of collisions, such as frontal collisions, rearward collisions, and side collisions, as well as rollovers. In particular, a load transfer path design is required to distribute the input load and reduce deformation of the vehicle body.

[0005] Therefore, the technology disclosed herein has been developed in consideration of the above-mentioned problems, and the purpose of the present disclosure is to improve load-bearing capacity and ensure a load transmission path when constructing a vehicle floor structure using fiber-reinforced resin composite materials.

[0006] In order to solve the above problem, according to one aspect of the technology disclosed herein, there is provided a vehicle body floor structure made of a fiber-reinforced resin composite material, comprising: a panel base material made of a fiber-reinforced resin composite material; and a continuous fiber-reinforced resin strip containing continuous fibers sewn onto the panel base material, with a first connecting portion and a second connecting portion at both ends that are respectively joined to other structural materials in the panel base material.

[0007] As described above, the technology disclosed herein can improve load-bearing capacity and ensure a load transmission path even when a vehicle body floor structure is constructed using a fiber-reinforced resin composite material.

[0008] Fig. 2 is a perspective view schematically showing a part of a vehicle body structure including a vehicle body floor structure according to the present embodiment. Fig. 3 is an explanatory diagram showing the vehicle body floor structure according to the present embodiment. Fig. 4 is an explanatory diagram showing an example of a method for fixing a winding portion to a panel base material in the vehicle body floor structure according to the present embodiment. Fig. 5 is a cross-sectional view taken along the arrows II in Fig. 2. Fig. 6 is a cross-sectional view of a connecting portion between a floor portion and a right center pillar of the vehicle body floor structure according to the present embodiment.

[0009] Preferred embodiments of the technology of the present disclosure will be described in detail below with reference to the accompanying drawings. In this specification and drawings, components having substantially the same functional configurations are designated by the same reference numerals, and redundant description will be omitted.

[0010] 1. Overview of Vehicle Body Structure First, an overview of a vehicle body structure including a vehicle body floor structure according to this embodiment will be described. Fig. 1 is a perspective view that schematically shows a portion of the vehicle body structure including the vehicle body floor structure. The vehicle body structure shown in Fig. 1 is shown generally as viewed from the rear left to the front right of the vehicle body. As shown in Fig. 1, in this specification, the vehicle width direction may be referred to as the X direction, the fore-and-aft direction of the vehicle body (vehicle length direction) as the Y direction, and the vehicle height direction as the Z direction.

[0011] The vehicle body structure shown in FIG. 1 includes a floor section 1, front pillars 2, center pillars 3, and side sills 6. The front pillars 2 have their lower ends connected to the front ends of the side sills 6 and their upper ends connected to the front ends of roof pillars (not shown). The center pillars 3 have their lower ends connected to the center of the side sills 6 in the vehicle length direction and their upper ends connected to the center of the roof pillars (not shown) in the vehicle length direction. The roof pillars (not shown) extend along the vehicle length in the upper part of the vehicle interior space and form the side portions of the vehicle roof. The side sills 6 extend along the vehicle length in the lower parts of the sides of the vehicle.

[0012] 1 has a tunnel 12 formed in the center of the vehicle width direction and extending along the vehicle length direction. The tunnel 12 forms a space in which a propeller shaft is disposed to transmit torque output from an engine or a drive motor mounted in the front of the vehicle body to the rear wheels, for example.

[0013] In addition, in the case of vehicles that do not have a propeller shaft, such as an electric vehicle that has a front-wheel drive motor and a rear-wheel drive motor on the front and rear sides of the vehicle body, or an electric vehicle that has four drive motors near each wheel to drive each wheel, the tunnel section 12 does not need to be provided in the floor section 1.

[0014] The front pillars 2, center pillars 3, roof pillars, and side sills 6 other than the floor portion 1 may each be configured as a member mainly made of fiber-reinforced resin. A member mainly made of fiber-reinforced resin refers to a composite material in which each member is configured with a panel of a fiber-reinforced resin composite material, and may also include members equipped with metal reinforcing members or fastening members.

[0015] A fiber-reinforced resin composite is a component obtained by molding a fiber-reinforced resin containing reinforcing fibers, mainly carbon fibers or aramid fibers, and a matrix resin, mainly thermoplastic or thermosetting resin. However, the types of reinforcing fibers are not limited to carbon fibers and aramid fibers. Furthermore, multiple types of fibers may be used as reinforcing fibers.

[0016] Examples of thermoplastic resins include polyethylene resin, polypropylene resin, polyvinyl chloride resin, ABS resin (acrylonitrile-butadiene-styrene copolymer synthetic resin), polystyrene resin, AS resin (acrylonitrile-styrene copolymer synthetic resin), polyamide resin, polyacetal resin, polycarbonate resin, polyester resin, PPS (polyphenylene sulfide) resin, fluororesin, polyetherimide resin, polyetherketone resin, and polyimide resin. The matrix resin may be composed of one of these thermoplastic resins or a mixture of two or more of them. Alternatively, the matrix resin may be a copolymer of these thermoplastic resins. When the thermoplastic resin is a mixture, a compatibilizer may be further used in combination. Furthermore, a flame retardant such as a bromine-based flame retardant, a silicon-based flame retardant, or red phosphorus may be added to the thermoplastic resin.

[0017] Examples of thermosetting resins include epoxy resins, unsaturated polyester resins, vinyl ester resins, phenolic resins, polyurethane resins, and silicone resins. The matrix resin may be composed of one of these thermosetting resins or a mixture of two or more of them. When these thermosetting resins are used, an appropriate curing agent or reaction accelerator may be added to the thermosetting resin.

[0018] The reinforcing fibers may contain an appropriate ratio of fibers oriented in the axial direction and fibers oriented in a direction intersecting the axial direction. In addition to continuous fibers extending continuously in a predetermined direction, the reinforcing fibers may also contain short fibers cut to a length of about several millimeters.

[0019] 2. Details of Vehicle Body Floor Structure Next, the vehicle body floor structure according to this embodiment will be described in detail.

[0020] 2 is a diagram illustrating the vehicle body floor structure of this embodiment. In the vehicle body floor structure of this embodiment, the floor portion 1 is configured to include a panel base material 10 and a plurality of continuous fiber reinforced resin strips 20. The plurality of continuous fiber reinforced resin strips 20 are components formed using a TFP (Talored Fiber Placement) method and are configured to include continuous fibers sewn onto the panel base material 10.

[0021] It should be noted that the continuous fiber reinforced resin band 20 placed on the panel base material 10 appears distorted to match the three-dimensional shape of the panel base material 10, but in Figure 2, for ease of understanding, the planar shape of the continuous fiber reinforced resin band 20 is shown without taking into account the uneven shape caused by the tunnel section 12.

[0022] The panel substrate 10 is a part that determines the overall shape of the floor section 1. Like the front pillars 2 and center pillars 3 described above, the panel substrate 10 is made of a fiber-reinforced resin composite material containing reinforcing fibers and a matrix resin, and has a predetermined rigidity or strength. When the panel substrate 10 contains continuous fibers, it is configured to include, for example, continuous fibers oriented in both the vehicle width direction and the vehicle body longitudinal direction, as well as continuous fibers oriented in directions at plus or minus 45 degrees relative to the vehicle body longitudinal direction and the vehicle width direction. This allows the panel substrate 10 itself to have strength against impact loads acting in all directions. The thickness of the panel substrate 10 is not particularly limited as long as it provides the desired rigidity, but can be, for example, within the range of 0.2 to 10.0 mm.

[0023] The panel base material 10 has a plurality of wound portions 40 on the front, rear, left, and right sides of the vehicle body. The wound portions 40 are members around which the continuous fibers that make up the plurality of continuous fiber reinforced resin strips 20 are wound, and form both end portions of each continuous fiber reinforced resin strip 20. The panel base material 10 of the floor portion 1 shown in FIG. 2 has 20 wound portions 40.

[0024] Specifically, two winding portions, a first winding portion 40a and a second winding portion 40b, are provided to the right of the tunnel portion 12 on the side E1 of the front side of the vehicle body of the panel base material 10. Furthermore, two winding portions, a third winding portion 40c and a fourth winding portion 40d, are provided to the left of the tunnel portion 12 on the side E1 of the front side of the vehicle body of the panel base material 10. The positions at which the first winding portion 40a and the second winding portion 40b, and the third winding portion 40c and the fourth winding portion 40d are provided are aligned with the positions of the connection portions where the floor portion 1 is joined to a toe board (not shown).

[0025] Similarly, a fifth winding portion 40e and a sixth winding portion 40f are provided to the right of the tunnel portion 12 on the side E2 of the panel base material 10 on the vehicle rear side. Furthermore, a seventh winding portion 40g and an eighth winding portion 40h are provided to the left of the tunnel portion 12 on the side E2 of the panel base material 10 on the vehicle rear side. The positions at which the fifth winding portion 40e and the sixth winding portion 40f, and the seventh winding portion 40g and the eighth winding portion 40h are provided are aligned with the positions of the connection portions where the floor portion 1 and a rear panel (not shown) are joined.

[0026] Furthermore, a ninth winding portion 40i, a tenth winding portion 40j, and an eleventh winding portion 40k are provided forward of the center of the side E3 on the right side of the vehicle body of the panel base material 10. The positions where the three winding portions are provided are aligned with the position of the connection portion where the floor portion 1 and the right front pillar 2 are joined. Furthermore, a twelfth winding portion 40l, a thirteenth winding portion 40m, and a fourteenth winding portion 40n are provided rearward of the center of the side E3 on the right side of the vehicle body of the panel base material 10. The positions where the three winding portions are provided are aligned with the position of the connection portion where the floor portion 1 and the right center pillar 3 are joined.

[0027] Furthermore, a 15th winding portion 40o, a 16th winding portion 40p, and a 17th winding portion 40q are provided forward of the center of the side E4 on the left side of the vehicle body of the panel base material 10. The positions where the three winding portions are provided are aligned with the position of the connection portion where the floor portion 1 and the left front pillar are joined. Furthermore, an 18th winding portion 40r, a 19th winding portion 40s, and a 20th winding portion 40t are provided rearward of the center of the side E4 on the left side of the vehicle body of the panel base material 10. The positions where the three winding portions are provided are aligned with the position of the connection portion where the floor portion 1 and the left center pillar are joined.

[0028] When it is not necessary to distinguish between the plurality of wound portions, they will be collectively referred to as wound portions 40. When it is not necessary to distinguish between the plurality of continuous fiber reinforced resin strips, they will be collectively referred to as continuous fiber reinforced resin strips 20.

[0029] FIG. 3 shows a plan view and a cross-sectional view taken along the line II-II of the panel substrate 10 to which the wound portion 40 is fixed. Each wound portion 40 can be fixed to the panel substrate 10 such that a portion of the wound portion 40 is embedded in the continuous fibers contained in the panel substrate 10, as shown in FIG. 3 . The wound portion 40 shown in FIG. 3 has a main body 41 around which the continuous fibers are wound and a base 43 having a larger diameter than the main body 41. The base 43 is pressed down by the fibers (fibers oriented in a direction intersecting at 90 degrees in the figure) that make up the panel substrate 10, thereby fixing the wound portion 40 to the panel substrate 10. This configuration allows the wound portion 40 to be firmly attached to the panel substrate 10 without cutting the continuous fibers that make up the panel substrate 10. However, the method of attaching the wound portion 40 to the panel substrate 10 is not limited to the above example.

[0030] Each of the multiple continuous fiber reinforced resin bands 20 is a component made of band-shaped fiber reinforced resin containing continuous reinforcing fibers and sewn onto the panel base material 10. Each continuous fiber reinforced resin band 20 is arranged with any two of the multiple winding sections 40 provided on the panel base material 10 as both ends. Specifically, each continuous fiber reinforced resin band 20 includes continuous fibers that are wound around any two of the winding sections 40 provided on the panel base material 10 and arranged so as to reciprocate multiple times between the two winding sections 40. The continuous fibers are arranged so as to reciprocate multiple times between the two winding sections 40 while being sewn to a predesigned position on the panel base material 10, and are then cured together with the matrix resin.

[0031] For example, the multiple continuous fiber reinforced resin bands 20 may include at least one longitudinal band portion arranged along the longitudinal direction of the vehicle body, at least one widthwise band portion arranged along the widthwise direction of the vehicle body, and at least one oblique band portion arranged in part or in whole in a direction intersecting the longitudinal direction of the vehicle body and the widthwise direction of the vehicle body.

[0032] The floor portion 1 shown in Figure 2 has a total of ten continuous fiber reinforced resin bands 20. Specifically, the multiple continuous fiber reinforced resin bands 20 include two longitudinal band portions 20a, 20b arranged along the longitudinal direction of the vehicle body, two transverse band portions 20c, 20d arranged along the vehicle width direction, and two oblique band portions 20e, 20f, part of which is arranged in a direction intersecting the longitudinal direction of the vehicle body and the vehicle width direction.

[0033] More specifically, the plurality of continuous fiber reinforced resin bands 20 include a first longitudinal band portion 20a disposed on the right side of the tunnel portion 12 along the longitudinal direction of the vehicle body, and second longitudinal band portions 20b disposed on the left side of the tunnel portion 12 along the longitudinal direction of the vehicle body. The first longitudinal band portion 20a includes continuous fiber wound around the second wound portion 40b and the sixth wound portion 40f and sewn to the panel base material 10. The second longitudinal band portion 20b includes continuous fiber wound around the third wound portion 40c and the seventh wound portion 40g and sewn to the panel base material 10.

[0034] The plurality of continuous fiber reinforced resin bands 20 include a first widthwise band portion 20c disposed along the vehicle width direction and forward of a center portion in the vehicle longitudinal direction, and a second widthwise band portion 20d disposed along the vehicle width direction and rearward of the center portion in the vehicle longitudinal direction. The first widthwise band portion 20c includes continuous fiber wound around an eleventh winding portion 40k and a seventeenth winding portion 40q and sewn to the panel base material 10. The second widthwise band portion 20d includes continuous fiber wound around a twelfth winding portion 40l and an eighteenth winding portion 40r and sewn to the panel base material 10.

[0035] The plurality of continuous fiber reinforced resin bands 20 include a first oblique band portion 20e disposed along the floor portion 1 from the front right to the rear left, and a second oblique band portion 20f disposed along the floor portion 1 from the front left to the rear right. The first oblique band portion 20e includes continuous fibers wound around a tenth winding portion 40j and a nineteenth winding portion 40s and sewn to the panel base material 10. The first oblique band portion 20e includes two first portions 20ea, 20ec disposed along the vehicle width direction from the tenth winding portion 40j provided in front of the vehicle right side edge and the nineteenth winding portion 40s provided behind the vehicle left side edge, and a second portion 20eb bent from each of the two first portions and disposed in a direction intersecting the vehicle body longitudinal direction and the vehicle width direction. The second oblique belt portion 20f includes continuous fibers wound around the thirteenth winding portion 40m and the sixteenth winding portion 40p and sewn to the panel base material 10. The second oblique belt portion 20f includes two first portions 20fa, 20fc arranged along the vehicle width direction from the sixteenth winding portion 40p provided in front of the left side of the vehicle and the thirteenth winding portion 40m provided behind the left side of the vehicle, and second portions 20fb bent from the two first portions and arranged in a direction intersecting the vehicle body longitudinal direction and the vehicle width direction.

[0036] Furthermore, each of the multiple continuous fiber reinforced resin strips 20 shown in FIG. 2 includes four orthogonal band portions, each including a first portion arranged along the vehicle longitudinal direction and a second portion bent from the first portion and arranged along the vehicle width direction. Specifically, the first orthogonal band portion 20g includes continuous fiber wound around the first winding portion 40a and the ninth winding portion 40i and sewn to the panel base material 10. This first orthogonal band portion 20g includes a first portion 20ga arranged along the vehicle longitudinal direction from the first winding portion 40a provided on the right side of the vehicle front edge E1, and a second portion 20gb bent from the first portion and arranged along the vehicle width direction toward the ninth winding portion 40i provided in front of the vehicle right edge E3. The second orthogonal band portion 20h includes continuous fiber wound around the fourth winding portion 40d and the fifteenth winding portion 40o and sewn to the panel base material 10. This second orthogonal band portion 20h has a first portion 20ha arranged along the fore-and-aft direction of the vehicle from the fourth winding portion 40d provided on the left side of the front edge E1 of the vehicle, and a second portion 20hb bent from the first portion and arranged along the vehicle width direction toward the 15th winding portion 40o provided in front of the left side edge E4 of the vehicle.

[0037] The third orthogonal belt portion 20i includes continuous fibers wound around the fifth winding portion 40e and the fourteenth winding portion 40n and sewn to the panel base material 10. The third orthogonal belt portion 20i has a first portion 20ia arranged along the vehicle longitudinal direction from the fifth winding portion 40e provided on the right side of the vehicle rear side E2, and a second portion 20ib bent from the first portion and arranged along the vehicle width direction toward the fourteenth winding portion 40n provided on the rear side of the vehicle right side E3. The fourth orthogonal belt portion 20j includes continuous fibers wound around the eighth winding portion 40h and the twentieth winding portion 40t and sewn to the panel base material 10. This fourth orthogonal band portion 20j has a first portion 20ja arranged along the fore-and-aft direction of the vehicle from the eighth winding portion 40h provided on the left side of the rear side E2 of the vehicle, and a second portion 20jb bent from the first portion and arranged along the vehicle width direction toward the 20th winding portion 40t provided on the rear side of the left side E4 of the vehicle.

[0038] FIG. 4 shows a cross section taken along the line II in FIG. 2 . At the position shown in FIG. 4 , the three band portions, namely, the second widthwise band portion 20d, the second oblique band portion 20f, and the third orthogonal band portion 20i, are collectively covered with the covering layer 23. Alternatively, each continuous fiber-reinforced resin band 20 is individually or collectively covered with the covering layer 23. The covering layer may be formed using a fiber-reinforced resin or a resin that does not contain reinforcing fibers. This prevents the continuous fibers of the continuous fiber-reinforced resin band 20 from being exposed to the surface. When a load is applied to the floor portion 1, the continuous fiber-reinforced resin band 20 is less likely to separate from the panel base material 10 and prevents the continuous fibers from unraveling.

[0039] In the vehicle body floor structure of this embodiment configured as described above, the plurality of continuous fiber reinforced resin strips 20 are arranged at either end at two of the connection portions (first connection portion and second connection portion) connected to the toe board, the left and right front pillars, the left and right center pillars, and the rear panel. Therefore, the load input to the vehicle body during a vehicle collision, rollover, etc. can be transmitted to other structural materials via the plurality of continuous fiber reinforced resin strips 20, thereby dispersing the collision load.

[0040] The continuous fiber reinforced resin bands 20 include a first longitudinal band portion 20a and a second longitudinal band portion 20b arranged along the vehicle longitudinal direction, a first widthwise band portion 20c and a second widthwise band portion 20d arranged along the vehicle width direction, and a first oblique band portion 20e and a second oblique band portion 20f arranged in a direction intersecting the vehicle longitudinal direction and the vehicle width direction. Therefore, the strength against compressive stress and tensile stress occurring in the vehicle longitudinal direction and the vehicle width direction is increased, and the torsional rigidity of the floor portion 1 is also increased.

[0041] As a result, the vehicle body floor structure of this embodiment has increased rigidity against a collision load in the vehicle's fore-and-aft direction (0-degree direction) or offset direction that is input through the toe board during a frontal collision such as a full-overlap collision or an offset collision, and is able to distribute the load. The vehicle body floor structure also has increased rigidity against a collision load and torsional load that are input through the left and right front pillars in the 0-degree direction, vehicle width direction (90-degree direction), or 45-degree direction during a frontal collision or a roof crush due to rollover, and is able to distribute the load.

[0042] The vehicle floor structure also has increased rigidity against a 90-degree collision load input through the left and right center pillars during a side collision, and can distribute the load. Furthermore, the vehicle floor structure has increased rigidity against a 0-degree or 45-degree collision load and a torsional load input through the rear panel during a front or rear collision, and can distribute the load.

[0043] In this way, the vehicle floor structure made of fiber-reinforced resin composite material improves the load-bearing capacity of the floor portion 1 and can efficiently distribute the load input during a collision, rollover, etc., thereby reducing deformation of the vehicle body and mitigating damage.

[0044] 3. Manufacturing Method Next, an example of a vehicle body floor structure using the TFP method will be described. However, the manufacturing method of the vehicle body floor structure described below is merely an example, and the method of manufacturing the vehicle body floor structure according to this embodiment is not limited to the following example.

[0045] First, CFRP prepregs are laminated using, for example, a molding die to form a semi-molten intermediate substrate corresponding to the panel substrate 10. At this time, winding sections 40 are attached to the positions of the pre-designed connections with other structural materials. In the case of the panel substrate 10 shown in FIG. 2 , each winding section 40 is provided with its axial direction aligned with the thickness direction of the intermediate substrate. For example, during the lamination of the prepregs, the main body 41 of the winding section 40 is inserted between the continuous fibers contained in the prepregs, and the base 43 of the winding section 40 is pressed by the continuous fibers, thereby embedding a portion of the winding section 40 in the intermediate substrate (see FIG. 3 ). The method for forming the intermediate substrate is not particularly limited.

[0046] Next, the continuous fiber is wound alternately around any two of the winding sections 40 while being sewn to the intermediate substrate along predesigned positions, thereby arranging a strip of continuous fiber on the intermediate substrate. The process of arranging the strip of continuous fiber is repeated at positions corresponding to each of the continuous fiber reinforced resin strips 20. Next, the strip of continuous fiber sewn to the intermediate substrate is impregnated with a matrix resin, and a plurality of continuous fiber reinforced resin strips 20 are preformed (TFP method).

[0047] Next, resin or CFRP prepreg is layered to cover one or more strip-shaped continuous fibers to form the covering layer 23. Next, the preformed continuous fiber reinforced resin strip and covering layer are cured together with the intermediate substrate, thereby manufacturing a floor section 1 having multiple continuous fiber reinforced resin strips 20 in predetermined positions.

[0048] 4. Modifications In the present embodiment, the winding portion 40 around which the continuous fibers that make up the continuous fiber reinforced resin strip 20 are wound may be used to connect the floor portion 1 to another structural material. Specifically, the first winding portion 40a, the second winding portion 40b, the third winding portion 40c, and the fourth winding portion 40d provided on the vehicle front side edge E1 of the floor portion 1 may be used as part of a connecting structure that connects the floor portion 1 to the toe board. Similarly, the fifth winding portion 40e, the sixth winding portion 40f, the seventh winding portion 40g, and the eighth winding portion 40h provided on the vehicle rear side edge E2 of the floor portion 1 may be used as part of a connecting structure that connects the floor portion 1 to the rear panel.

[0049] Furthermore, the ninth winding portion 40i, the tenth winding portion 40j, and the eleventh winding portion 40k provided on the front side of the side E3 of the floor portion 1 on the vehicle right side may be used as part of a connecting structure that connects the floor portion 1 to the right front pillar. Furthermore, the twelfth winding portion 40l, the thirteenth winding portion 40m, and the fourteenth winding portion 40n provided on the rear side of the side E3 of the floor portion 1 on the vehicle right side may be used as part of a connecting structure that connects the floor portion 1 to the right center pillar. Similarly, the fifteenth winding portion 40o, the sixteenth winding portion 40p, and the seventeenth winding portion 40q provided on the front side of the side E4 of the floor portion 1 on the vehicle left side may be used as part of a connecting structure that connects the floor portion 1 to the left front pillar. In addition, the 18th winding portion 40r, the 19th winding portion 40s, and the 20th winding portion 40t provided on the rear side of the left side E4 of the vehicle of the floor portion 1 may be used as part of the connecting structure connecting the floor portion 1 to the left center pillar.

[0050] FIG. 5 is a cross-sectional view of the connection portion between the floor portion 1 and the right center pillar 3, taken along the direction in which the first portion 20fc of the second oblique band portion 20f extends. The thirteenth winding portion 40m penetrates the panel base material 10, with both axial ends exposed on both surfaces of the floor portion 1. The thirteenth winding portion 40m has bolt holes 41c formed along the axis and opening at both axial ends of the thirteenth winding portion 40m. A connecting bolt 61 serving as a connecting member for connecting the floor portion 1 and the right center pillar 3 is inserted into the bolt hole 41c. The thirteenth winding portion 40m, around which the continuous fiber is wound, is inserted into a hole 6a provided in the side sill 6 and a hole 3b provided in the right center pillar 3, and the floor portion 1, the side sill 6, and the right center pillar 3 are fastened together using the connecting bolt 61 and a nut 63.

[0051] Although not shown in the drawings, each of the winding portions 40 is used to connect the floor portion 1 to the toe board, rear panel, front pillar, and center pillar, respectively.

[0052] In this way, by using the wound portion 40 as part of the connecting structure that connects the floor portion 1 to other structural materials, it is no longer necessary to provide a structure for positioning the other structural materials relative to the floor portion 1, or a separate connecting member for connecting the floor portion 1 to other structural materials. Furthermore, because each continuous fiber reinforced resin band 20 is firmly connected to the other structural materials, loads are efficiently transmitted from the other structural materials to the continuous fiber reinforced resin bands 20 in the event of a vehicle collision or rollover, and the load can be efficiently dispersed via the continuous fiber reinforced resin bands 20.

[0053] In particular, while conventional steel floors have been secured by spot welding or other methods to ensure joint strength, spot welding is not an option for floors made of fiber-reinforced resin composites. Furthermore, if the floor and other structural materials are bonded using adhesive, for example, there is a risk of the floor easily separating when a load is applied. In response to this issue, the wound portion can be used as part of the connecting structure, passing through holes in the other structural materials and fastening them together to ensure the joint strength between the floor and the other structural materials.

[0054] Although preferred embodiments of the technology of the present disclosure have been described in detail above with reference to the accompanying drawings, the technology of the present disclosure is not limited to these examples. It is clear that a person skilled in the art of the technology to which the present disclosure pertains can conceive of various modified or altered examples within the scope of the technical ideas described in the claims, and it is understood that these also naturally fall within the technical scope of the present disclosure. Furthermore, combinations of the above-described embodiments and each modified example also naturally fall within the technical scope of the present disclosure.

[0055] For example, in the above embodiment, a continuous fiber reinforced resin strip having two predetermined winding portions at both ends is illustrated, but the continuous fiber reinforced resin strip in the technology of the present disclosure is not limited to these examples. A continuous fiber reinforced resin strip may be arranged with two winding portions at both ends other than the combination of two winding portions illustrated above. Furthermore, the planar patterns of each continuous fiber reinforced resin strip are not limited to the examples in the above embodiment, and may be designed arbitrarily according to a desired load transfer path.

[0056] 1: floor portion, 2: right front pillar, 3: right center pillar, 6: side sill, 10: panel base material, 12: tunnel portion, 20: continuous fiber reinforced resin band, 20a: first longitudinal band portion, 20b: second longitudinal band portion, 20c: first widthwise band portion, 20d: second widthwise band portion, 20e: first oblique direction band portion, 20f: second oblique direction band portion, 20g: first orthogonal band portion, 20h: second orthogonal band portion, 20i: third orthogonal band portion, 20j: fourth orthogonal band portion, 23: coating layer, 40: wound portion, 41: main body portion, 43: base portion, 61: connecting bolt, 63: nut

Claims

1. A vehicle body floor structure made of a fiber-reinforced resin composite material, a panel base material made of a fiber reinforced resin composite material; a plurality of continuous fiber reinforced resin strips including continuous fibers sewn onto the panel base material, the continuous fiber reinforced resin strips being arranged with a first connecting portion and a second connecting portion at both ends, the first connecting portion and the second connecting portion being respectively joined to other structural materials in the panel base material; The plurality of continuous fiber reinforced resin bands are At least one longitudinal band portion disposed along the longitudinal direction of the vehicle body; At least one widthwise band portion disposed along the vehicle width direction; at least one oblique band-shaped portion, a part of which or the whole of which is disposed in a direction intersecting the vehicle body longitudinal direction and the vehicle width direction, The inclined band portion is a first portion disposed along the vehicle body longitudinal direction or the vehicle width direction; a second portion bent from the first portion and disposed in a direction intersecting the vehicle body longitudinal direction and the vehicle width direction, Body floor structure.

2. a winding portion provided at the first connecting portion and the second connecting portion, around which the continuous fiber is wound; The continuous fiber is the winding portion is wound around the winding portion provided on the first connection portion and the second connection portion, and the winding portion is wound back and forth between the first connection portion and the second connection portion multiple times. The vehicle body floor structure according to claim 1.

3. The vehicle body floor structure according to claim 2 , wherein the wound portion is used in a connecting structure that connects the vehicle body floor structure and the other structural member.