JP6551700B2 - Vehicle body structure - Google Patents

Description

  The present invention relates to a vehicle in which one end and the other end in the longitudinal direction of a long member made of synthetic resin reinforced by a reinforcing material oriented in a predetermined direction are connected to the vehicle body side via a pair of fastening members. It relates to the body structure.

Conventionally, it is known that panel members such as a floor panel, a bonnet, a trunk lid, and a roof panel are easily deformed by an input from a suspension.
In particular, since the floor panel forming the bottom surface of the cabin is provided with a tunnel section extending in the front-rear direction bulging toward the cabin at the middle portion in the vehicle width direction, it is more rigid than a flat structure without a tunnel section. As a result, the membrane vibration that moves up and down increases.
This increased vibration of the floor panel causes vehicle interior noise, which may reduce ride comfort performance.

In recent years, Carbon-Fiber-Reinforced-Plastic (CFRP) has material properties that combine high specific strength (strength / specific gravity) and high specific rigidity (rigidity / specific gravity), so-called lightness, strength and rigidity. Therefore, it is widely used as a structural material for aircraft and vehicles.
In this carbon fiber reinforced resin, carbon fibers share mechanical properties such as strength, and the matrix resin (matrix) shares the stress transfer function between carbon fibers and the fiber protection function, so the fiber direction and non-fiber direction are not It is an anisotropic material whose physical properties vary greatly depending on the fiber direction (direction in which the load is applied).
Based on these findings, the present applicant has proposed a technique using a carbon fiber reinforced resin as a reinforcing member of a vehicle body.

The vehicle panel structure of Patent Document 1 includes a damping panel member connected to a side sill and a second floor frame at four corners. The damping panel member includes a viscoelastic member made of a panel-like synthetic resin, and the viscoelasticity. It is made up of a carbon fiber member embedded in the member and fixed to the four corners of the damping panel member, and is more rigid than the visco-elastic member and longitudinally arranged.
As a result, while constituting the undercover that isolates noise from the outside, the film vibration generated on the undercover itself is attenuated.
In the vehicle body reinforcing structure of Patent Document 2, both longitudinal end portions of a plurality of strip members made of carbon fiber reinforced resin in which carbon fibers are arranged in the longitudinal direction are the lower portion of the floor panel and the front and rear direction. They are connected to vehicle body side connecting portions that are spaced apart in the vehicle width direction.
Thus, vibration damping that occurs in the entire vehicle body is intended.

Usually, the vibration input to the carbon fiber reinforced resin is converted into strain energy and kinetic energy, and this strain energy is once stored as shear strain in the member.
Thereafter, the accumulated strain energy (shear strain) is converted back into kinetic energy. At this time, a part of the strain energy is converted into heat energy and dissipated.
Therefore, by increasing the strain energy accumulated inside the carbon fiber reinforced resin, the dissipated thermal energy can be increased, and as a result, the vibration damping ability of the vehicle can be increased.
In the reinforcing structure of the vehicle body of Patent Document 2, when a torsional moment based on the vibration of the floor panel is applied to the band plate material, the carbon fibers are torsionally deformed independently, so that the base material existing between the carbon fibers is subjected to shear deformation. Although it occurs, since the base material between the carbon fibers is a minute amount, the shear strain increases in the base material between the carbon fibers, and accordingly, the strain energy accumulated in the base material is increased.

JP, 2015-174611, A JP, 2017-061170, A

The behavior modes of the vehicle body that affect the ride comfort of the occupant are mainly classified into two.
The first vehicle body mode is a vehicle body torsion mode accompanying torsional deformation.
The vehicle body torsion mode is a torsional displacement motion of the entire vehicle body caused by a phase delay based on a torsional moment about the vehicle body center axis when the vehicle is turning, and is a vehicle body mode related to rigidity.
The second vehicle body mode is a membrane vibration mode accompanying bending deformation.
This membrane vibration mode is a vertical displacement movement by the floor panel when a protrusion present on the road surface runs up or travels on a rough road surface, and is a vehicle body mode related to vibration.

In the case of a carbon fiber reinforced resin reinforced with a reinforcing fiber oriented in the longitudinal direction as a main component, since the torsion loss coefficient is an anisotropic material having a value higher than the bending loss coefficient, There is a possibility that the vibration damping ability (strain energy storage ability) possessed by the band plate material can not be effectively utilized (used up).
That is, even if the carbon fiber reinforced resin constituting the strip material has a high strain energy storage capability as a physical property of the material itself, the strip material is the same as the floor panel (or a frame member connected to the floor panel). When performing deformation behavior, only the strain energy corresponding to the torsional deformation associated with this behavior can be stored inside the strip, and the bending deformation accompanying the behavior (bending direction load) can contribute to vibration damping. Can not.

Therefore, the present inventor conducted verification analysis on the strain energy storage characteristics of the carbon fiber reinforced resin.
As shown in FIG. 10, when looking at the entire structure of the vehicle with respect to strain energy, the normal vehicle structure has a vehicle body system mechanism with a spring constant k _b , a carbon fiber reinforced resin part with a spring constant k _cf and a spring constant k _j . It can be expressed as a simple spring model in which a member system mechanism including a fastening portion is connected in parallel.
Therefore, the correlation between the rigidity of the carbon fiber reinforced resin portion and the accumulated strain energy was determined by numerically analyzing this simple spring model.
As shown in FIG. 11, as a result of the numerical analysis, the strain energy accumulated in the carbon fiber reinforced resin is lower as the rigidity is higher, except for a region with extremely low rigidity. The physical property that the peak point of energy exists was discovered.

Based on the above findings, when the rigidity of the carbon fiber reinforced resin is lowered, the strain energy accumulated in the carbon fiber reinforced resin can be increased, and the vibration damping ability can be increased.
Usually, the method of reducing the rigidity is performed by changing the configuration of the member itself by forming a fragile portion, for example, by forming an opening in the constituent wall portion.
However, changing the configuration of the members requires a separate work process, and may affect other members arranged in the vicinity.
Therefore, a specific vehicle body configuration for efficiently increasing the strain energy accumulated in the resin based on the behavior mode of the vehicle body without changing the structure of members has not been established yet.

  An object of the present invention is to provide a vehicle body structure and the like of a vehicle that can improve the vibration damping capability based on the behavior mode of the vehicle body without changing the structure of the members.

According to the first aspect of the invention, the longitudinal end of the long member made of synthetic resin reinforced by the reinforcing material oriented in the predetermined direction is connected to the vehicle body side via the pair of fastening members. In the vehicle body structure of the vehicle, the elongated member has a plurality of synthetic resin layers made of the synthetic resin, and among the synthetic resin layers, the reinforcing material of the plurality of first synthetic resin layers on the inner side in the thickness direction is the first. The reinforcing material of the second synthetic resin layer, which is oriented in one direction and is outermost in the thickness direction, is oriented in a second direction intersecting the first direction at an acute angle, and bulges toward the vehicle compartment at the center portion in the vehicle width direction. A tunnel portion extending in the front-rear direction of the vehicle body is formed, and the long member connects the one end portion and the other end portion of the tunnel portion in the vehicle width direction via the pair of fastening members. It is characterized.

According to this configuration, the reinforcements of the plurality of first synthetic resin layers on the inner side in the thickness direction are oriented in the first direction, and the reinforcements of the second synthetic resin layer on the outermost side in the thickness direction are the first direction. Since it is oriented in the second direction crossing at an acute angle, the twisting direction deformation of the long member can be generated using the bending direction load acting on the long member.
In other words, the bending direction load acting on the long member can be converted into the torsional direction load based on the behavior mode of the vehicle body, and the strain energy stored in the resin can be efficiently increased without changing the structure. can do. Moreover, the vibration displacement of the tunnel part which is the main vibration source of a floor panel can be taken in into a long member, and rigidity ensuring of a floor panel and improvement of a vibration damping capacity can be made compatible.

The invention of claim 2 is characterized in that, in the invention of claim 1, the first direction is a longitudinal direction of the elongated member.
According to this configuration, the axial rigidity of the long member can be contributed to the vehicle body rigidity.

The invention of claim 3 is characterized in that, in the invention of claim 1 or 2, the second synthetic resin layer is disposed in the outermost layer on one side in the thickness direction and the outermost layer on the other side in the thickness direction. And
According to this structure, the conversion efficiency which converts the bending direction load which acts on a elongate member to a twist direction load can be made high.

The invention of claim 4 is characterized in that, in the invention of any one of claims 1 to 3, the reinforcing material is a fiber reinforcing material.
According to this configuration, it is possible to convert the load in the bending direction into the load in the twisting direction by the long member reinforced with the fiber reinforcing material.

The invention of claim 5 is the invention of claim 4, wherein the reinforcing material is a carbon fiber reinforcing material.
According to this configuration, it is possible to convert a bending direction load into a torsional direction load while reducing the weight.

The invention according to a sixth aspect is the invention according to any one of the first to fifth aspects, wherein a plurality of the long members are provided, and the plurality of long members are a line with respect to a vehicle center line extending in the vehicle longitudinal direction. It is characterized by being arranged symmetrically.
According to this configuration, it is possible to obtain a sense of security (box feeling) that does not cause a phase delay of vehicle body vibration due to the long member.

  According to the vehicle body structure of the present invention, it is possible to improve the vibration damping capability based on the behavior mode of the vehicle body without changing the structure of the members.

It is the figure which looked at the vehicle concerning Example 1 from the slanting lower part. It is a partial bottom view of vehicles. It is the figure which looked at the vehicle interior from diagonally backward. It is a perspective view of a bar member. It is the elements on larger scale of a bar member. It is explanatory drawing of the manufacture procedure of a bar member. It is explanatory drawing of the model which concerns on verification analysis. It is explanatory drawing of the analysis principle which concerns on verification analysis. It is a graph which shows a verification result. It is a simple spring model of a vehicle. It is a graph which shows the relationship between the rigidity of carbon fiber reinforced resin, and the strain energy accumulated in carbon fiber reinforced resin.

Hereinafter, embodiments of the present invention will be described in detail based on the drawings.
The following description exemplifies a case where the present invention is applied to a lower body structure of a vehicle, and does not limit the present invention, its application, or its use.
In the drawing, the arrow F indicates the front, the arrow L indicates the left, and the arrow U indicates the upper side.

Embodiment 1 of the present invention will be described below with reference to FIGS.
First, the entire configuration of the vehicle V will be described.
As shown in FIGS. 1 to 3, the vehicle V is formed of a monocoque type body, and is formed to rise upward from the front end portion of the floor panel 1 and the floor panel 1 forming the bottom of the cabin R A dash panel 2 that partitions the engine room E and the vehicle compartment R, a pair of left and right front side frames 3 that extend forward from the dash panel 2, and a pair of left and right rear sides that extend rearward from the rear end portion of the floor panel 1 It has a frame 4 and the like.

  The vehicle V includes a pair of left and right side sills 5 disposed at the left and right ends of the floor panel 1, a pair of left and right hinge pillars 6 extending upward from the front ends of the pair of side sills 5, and a pair A pair of left and right center pillars 7 extending upward from the middle portion of the side sill 5, a pair of left and right front pillars 8 extending rearwardly upward from the upper ends of the pair of hinge pillars 6, and a pair of front A pair of left and right roof side rails 9 and the like that extend rearward from the rear end portion of the pillar 8 and are connected to the upper end portions of the pair of center pillars 7 are provided.

Next, the floor panel 1 will be described.
As shown in FIGS. 1 to 3, the floor panel 1 is formed in a substantially rectangular shape in plan view, and includes a tunnel portion 10 that extends in the front-rear direction and protrudes toward the passenger compartment R at the center in the vehicle width direction. ing.
At the left and right ends of the tunnel portion 10, there are provided a pair of tunnel side frames 11 each having a substantially hat-shaped cross section extending in the front and rear direction. The tunnel side frames 11 cooperate with the lower surface of the floor panel 1 to be substantially parallel. A closed cross section having a substantially rectangular cross section extending in the front-rear direction is formed.
Between the pair of left and right side sills 5 and the pair of left and right tunnel side frames 11, a floor frame 12 having a substantially hat-shaped cross section extending in the front-rear direction is provided.
The floor frame 12 is disposed so as to move outward in the vehicle width direction toward the rear side, and forms a closed cross section having a substantially rectangular cross section extending in the front-rear direction in cooperation with the lower surface of the floor panel 1.
The front end portion of the floor frame 12 is connected to the rear end portion of the front side frame 3, and the rear end portion is connected to the front end portion of the rear side frame 4.

The floor panel 1 includes cross members 13 and 14 that extend in the left and right across the tunnel portion 10 in the passenger compartment R. Each of the cross members 13 and 14 is formed in a substantially hat-shaped cross section, and has a substantially rectangular cross section extending from the side wall portion of the tunnel portion 10 to the side wall portion of the side sill 5 in cooperation with the upper surface of the floor panel 1. The closed cross-sections of the
The cross member 13 is disposed at a position corresponding to an intermediate portion between the hinge pillar 6 and the center pillar 7, and is joined to the front side wall portion of the cross member 13 with the floor panel 1 interposed at the front end side portion of the floor frame 12. The rear end of the upper frame 15 is connected.
The cross member 14 is disposed substantially parallel to the cross member 13 and disposed at a position corresponding to the center pillar 7.

In the passenger compartment R, a pair of left and right front seats (not shown) are mounted. Each sheet is provided with a seat frame (not shown) for securing the strength and rigidity of the sheet, and is supported by a pair of left and right seat rails 16 so as to be slidable in the front-rear direction.
As shown in FIG. 2, of the pair of seat rails 16, the seat rail 16 on the outer side in the vehicle width direction is fixed at the front end portion to the outer side portion in the vehicle width direction of the cross member 13, and the rear end portion is the vehicle of the cross member 14. It is fixed to the width direction outside part. Similarly, the seat rail 16 on the inner side in the vehicle width direction of the pair of seat rails 16 is fixed to the inner side in the vehicle width direction of the cross member 13 and the rear end portion is the inner side portion in the vehicle width direction of the cross member 14. It is fixed to
A plurality (for example, 13) of bar members 21 to 27 (long members) are disposed below the floor panel 1.

Next, the plurality of bar members 21 to 27 will be described.
The plurality of bar members 21 to 27 dampen the vibration caused by the phase delay based on the torsional moment generated around the vehicle body central axis orthogonal to the vehicle width direction and the vertical vibration of the floor panel 1 due to the vertical bending deformation of the vehicle body central axis. It is configured to be possible.
As shown in FIGS. 1 and 2, the plurality of bar members 21 to 27 are arranged at symmetrical positions with respect to the vehicle body central axis. The bar members 21 to 27 are mainly described, and the description of the bar members 21 to 27 arranged on the right side of the vehicle body is omitted.

As shown in FIG. 4, the bar member 21 has two pairs of ridge lines, is formed in a substantially rectangular shape whose cross section is horizontally long, and is formed in an elongated shape extending in the longitudinal direction. The bar member 21 has a mounting portion 21s having a bolt hole at one end in the longitudinal direction, and a mounting portion 21t having a bolt hole at the other end in the longitudinal direction.
As shown in FIGS. 1 and 2, when the bar member 21 is attached to the floor panel 1 (side sill 5) via the bolt 31 and the nut 32, the attachment portions 21s and 21b are respectively held by the pair of attachment plates 33. There is.

As shown in FIG. 5, the bar member 21 is integrally formed by molding (for example, an autoclave or the like) a carbon fiber reinforced resin (CFRP) in which the carbon fiber F is used as a reinforcing material.
The thickness direction inner portion (upper and lower direction middle portion) corresponding to the majority of the bar member 21 is formed of a plurality of first synthetic resin layers p1, and the thickness direction one side outermost layer and the other side outermost layer portion of the bar member 21 The (uppermost layer and lowermost layer portions) are each formed by the second synthetic resin layer p2.
The carbon fibers F are respectively constituted by fiber bundles (tows) in which a predetermined number (for example, 12 k) of single fibers (filaments) extending uniformly in the orientation direction are bundled.
The diameter of a single fiber of carbon fiber F is, for example, 7 to 10 μm. For the base material M of the bar member 21, for example, a thermosetting epoxy synthetic resin is used.

The carbon fibers F of each first synthetic resin layer p1 are each oriented at 0 ° so as to be parallel to the longitudinal direction of the bar member 21, and the carbon fibers F of each second synthetic resin layer p2 are longitudinal of the bar member 21. Each is oriented at 45 ° so as to intersect the direction at an acute angle.
Since carbon fiber F of the 2nd synthetic resin layer p2 of the top layer which intersects carbon fiber F of the 1st synthetic resin layer p1 is the same orientation as carbon fiber F of the 2nd synthetic resin layer p2 of the lowest layer by this, When a downward bending load is applied to the bar member 21, a torsional moment is generated around the center of gravity of the bar member 21. The direction parallel to the longitudinal direction of the bar member 21 is defined as 0 ° orientation.
The bar members 22 to 27 are configured with the same specifications except that the length in the length direction is different from that of the bar member 21. Each of the bar members 22 to 27 includes an attachment portion 22 s to 27 s, an attachment portion 22 t to 27 t, and an opening portion 22 e to 27 e. Have.

The bar members 21 to 27 are arranged so that the attachment portions 21s to 27s and the attachment portions 21t to 27t are attached to the vehicle body side member, and the other intermediate portions are separated from the other members.
As shown in FIGS. 1 and 2, the bar member 21 has a mounting portion 21 s fixed to a lower portion of the right side sill 5 corresponding to the front end of the kick-up via a bracket (not shown), and the mounting portion 21 t is more than the kick-up. It is fixed to the lower part of the right tunnel frame part 11 in front and behind the cross member 14 via a bracket (not shown).
The bar member 22 has a mounting portion 22s fixed at the same position as the mounting portion 21t, and the mounting portion 22t is a bracket (not shown) below the left tunnel frame portion 11 corresponding to the right end portion (inner side in the vehicle width direction) of the cross member 14. ) Is fixed.

The bar member 23 has a mounting portion 23 s fixed at the same position as the mounting portion 22 t, and the mounting portion 23 t is a bracket (not shown) below the left side sill 5 corresponding to the left end portion (outer portion in the vehicle width direction) of the cross member 13. It is fixed through. Therefore, the bar member 23 is configured to connect the pair of seat rails 16 diagonally in a plan view.
The bar member 24 has a mounting portion 24s fixed at the same position as the mounting portion 23t, and the mounting portion 24t is fixed to a lower portion of the front end side portion of the left tunnel frame portion 11 via a bracket (not shown).

The bar member 25 has an attachment portion 25s fixed at the same position as the attachment portion 24t, and the attachment portion 25t is fixed to the lower part of the front end side portion of the right tunnel frame portion 11 via a bracket (not shown). The bar member 26 has a mounting portion 26 s fixed at the same position as the mounting portion 25 t, and the mounting portion 26 t is a bracket (not shown) below the left tunnel frame portion 11 behind the cross member 13 and ahead of the cross member 13. It is fixed through.
The bar member 27 has a mounting portion 27 s fixed at the same position as the mounting portion 26 t, and a bracket (not shown) is attached to the lower portion of the left tunnel frame portion 11 in front of the kick-up and rearward of the cross member 14. It is fixed through.
The bar members 21 to 24 and 26 form a predetermined intersection angle with respect to the front-rear direction and the left-right direction.

Next, the manufacturing procedure of the bar members 21 to 27 will be described.
As shown in FIG. 6 (a), a carbon fiber F arranged in one direction is impregnated with a synthetic resin (melted base material M) to create a prepreg sheet.
Next, as shown in FIG. 6B, the first prepreg sheet q1 corresponding to the first synthetic resin layer p1 in which the carbon fiber F is set at the orientation 0 °, and the carbon fiber F are set at the orientation 45 ° And a second prepreg sheet q2 corresponding to the second synthetic resin layer p2.
Next, as shown in FIG. 6C, a plurality of first prepreg sheets q1 are laminated, and a second prepreg sheet q2 is laminated respectively on the front and back surfaces of the laminate of the first prepreg sheet q1.
Next, as shown in FIG.6 (d), the laminated body P of the 1st, 2nd prepreg sheet | seat q1, q2 is bagged using a bagging film.
Next, as shown in FIG. 6 (e), the laminated body P of the bagged first and second prepreg sheets q1 and q2 is cured using an autoclave pot and subjected to predetermined processing to form a bar member 21. (FIG. 6 (f)).

Next, functions and effects of the vehicle body structure of the vehicle according to the present embodiment will be described.
In the explanation of the function and effect, the strain energy accumulated in the bar member in the membrane vibration mode was analyzed by CAE (Computer Aided Engineering).
First, the basic concept of this analysis will be described.
As shown in FIGS. 7 (a) and 7 (b), a model MA in which a multilayer portion with an orientation of 0 ° is formed in the middle portion and a layer with an orientation of 45 ° is formed in the uppermost lower layer is all A model MB made of carbon fiber reinforced resin was prepared. The model MA is composed of an oriented 0 ° layer of 30 mm × 1.8 mm × 300 mm and front and back layers of 0.1 mm each, and the model MB is composed of an oriented 0 ° layer of 30 mm × 2 mm × 300 mm. The carbon fiber reinforced resin has a fiber content of 60% and a fiber strength of 230 GPa.
As shown in FIG. 8A, both ends of the models MA and MB in the longitudinal direction are held by a pair of jigs D. Next, as shown in FIG. 8 (b), by turning a pair of jigs D in the direction of the arrow, a pure bending moment of 1000 Nm is input to both ends in the longitudinal direction of the models MA and MB. The strain energy accumulated in the orientation 0 ° portion of MA and MB was analyzed.

The analysis result is shown in FIG.
As shown in FIG. 9, strain energy was accumulated in the 0 ° orientation portion of the model MA, and no strain energy was accumulated in the 0 ° orientation portion of the model MB.
From this result, it was found that the bending direction load acting on the model MA was converted into the torsional direction load by forming the layer of orientation 45 ° in the uppermost layer of the multilayer portion of orientation 0 °.

According to the vehicle body structure of the vehicle V, the reinforcements of the plurality of first synthetic resin layers p1 on the inner side in the thickness direction are oriented at 0 ° which is the first direction, and the second synthetic resin layer p2 on the outermost side in the thickness direction Since the reinforcing material is oriented at 45 °, which is the second direction, it is possible to generate a torsional deformation of the bar member 21 using a bending direction load acting on the bar member 21.
That is, the load in the bending direction acting on the bar member 21 can be converted into the load in the torsion direction based on the behavior mode of the vehicle body, and strain energy accumulated in the resin at the material level can be efficiently increased without structural change. can do.

Since the first direction is the longitudinal direction of the bar member 21, the axial rigidity of the bar member 21 can contribute to the vehicle body rigidity.
Since the second synthetic resin layer p2 is disposed on the uppermost layer on one side in the thickness direction and the lowermost layer on the other side in the thickness direction, the conversion efficiency for converting the bending direction load acting on the bar member 21 into the torsional direction load Can be raised.

Since the reinforcing material is a fiber reinforcing material, the bending direction load can be converted into the twisting direction load by the bar members 21 to 27 reinforced with the carbon fiber F.
Since the reinforcing material is carbon fiber F, the bending direction load can be converted into the torsional direction load while reducing the weight.

Since there are a plurality of bar members 21 to 27 and the plurality of bar members 21 to 24 and 26 are arranged symmetrically with respect to the vehicle body center line extending in the longitudinal direction of the vehicle body, the vehicle body vibrations are caused by the bar members 21 to 24 and 26. It is possible to obtain a sense of security (box feeling) that does not cause the phase lag.
A tunnel portion 10 that bulges toward the passenger compartment side and extends in the longitudinal direction of the vehicle body is formed at the center in the vehicle width direction, and the bar members 22, 25, and 26 Are coupled via a pair of fastening members 31 and 32, the vibration displacement of the tunnel portion 10 which is the main vibration source of the floor panel 1 can be taken into the bar members 22, 25 and 26. It is possible to achieve both ensuring rigidity and improving vibration damping capability.

Next, a modification in which the embodiment is partially changed will be described.
1) In the above embodiment, an example was described in which the orientation of the carbon fiber in the middle in the thickness direction was 0 ° and the orientation of the carbon fibers in the front and back layers was 45 °, but at least the carbon fibers in the middle in the thickness direction The orientation of the carbon fibers in the front or back layer may intersect at an acute angle with respect to the orientation, and the orientation of the carbon fibers in the front and back layers can be arbitrarily selected between orientations of 1 to 89 °. In addition, the orientation of the carbon fiber in the middle in the thickness direction can also be set to other than 0 °, and can also be set to the orientation that contributes most to the vehicle body stiffness or the orientation that maximizes the damping capacity.
Further, it is not necessary to make the front and back layers different in orientation from the orientation of the carbon fiber in the middle in the thickness direction, and at least one of them is different from the orientation in the middle in the thickness direction. Can play.

2) In the above embodiment, an example in which the plurality of first synthetic resin layers and the second synthetic resin layer are structurally integrated has been described, but only the plurality of first synthetic resin layers are structurally integrated After creating the front and back side second synthetic resin layers separately, the second synthetic resin layers may be adhered to the front and back surfaces of the plurality of first synthetic resin layers with an adhesive or the like.

3] In the above-described embodiment, an example of arrangement of a plurality of bar members fastened at two points has been described. It is only necessary that the contribution ratio is higher than the contribution ratio to other rigidity, and the arrangement position can be set as appropriate.

4) In the above embodiment, the carbon fiber of the bar member has been described as extending uniformly from one end to the other. However, it is sufficient that the orientation of the reinforcing material is at least uniform. Cellulosic fibers and inorganic glass fibers may be used, and inorganic talc may be used.

5) In the above-described embodiment, an example in which attachment portions having bolt holes are provided at both end portions of the bar member, and these attachment portions are sandwiched between attachment plates and attached to the vehicle body using bolts and nuts has been described. You may attach a bar member to a vehicle body via a connection member. In this case, a metal connecting member having a bolt hole is prepared, one side is made into a bag shape, the end of the connecting member and the end of the bar member are fitted, and then bonded or mechanically connected (rivet or screw) ).

6) In addition, those skilled in the art can implement the present invention in a form in which various modifications are added to the above-described embodiment or in a form in which each embodiment is combined without departing from the gist of the present invention. It also includes various modifications.

DESCRIPTION OF SYMBOLS 10 Tunnel part 21-27 Bar member 31 Bolt 32 Nut V Vehicle F Carbon fiber M Base material p1 1st synthetic resin material p2 2nd synthetic resin material

Claims (6)

In the vehicle body structure of a vehicle in which one end and the other end in the longitudinal direction of a long member made of synthetic resin reinforced by a reinforcing material oriented in a predetermined direction are connected to the vehicle body via a pair of fastening members,
The long member has a plurality of synthetic resin layers made of the synthetic resin,
Among the synthetic resin layers, the reinforcements of the plurality of first synthetic resin layers inside in the thickness direction are oriented in the first direction, and the reinforcements of the second synthetic resin layer outermost in the thickness direction are in the first direction Oriented in a second direction intersecting at an acute angle to ,
A tunnel portion that bulges toward the passenger compartment side and extends in the longitudinal direction of the vehicle body is formed at the center in the vehicle width direction,
A vehicle body structure of a vehicle, wherein the long member connects one side end portion in the vehicle width direction of the tunnel portion and the other side end portion via the pair of fastening members .   The vehicle body structure according to claim 1, wherein the first direction is a longitudinal direction of the long member.   The vehicle body structure of a vehicle according to claim 1 or 2, wherein the second synthetic resin layer is disposed on the outermost layer on one side in the thickness direction and the outermost layer on the other side in the thickness direction.   The vehicle body structure according to any one of claims 1 to 3, wherein the reinforcing material is a fiber reinforcing material.   The vehicle body structure according to claim 4, wherein the reinforcing material is a carbon fiber reinforcing material. Having a plurality of the long members,
The vehicle body structure of a vehicle according to any one of claims 1 to 5, wherein the plurality of elongated members are disposed in line symmetry with respect to a vehicle body center line extending in a vehicle longitudinal direction.