JP6969673B2 - T-shaped joint structure - Google Patents

Description

The present invention relates to a T-shaped joint structure which is a joint structure between members.

As a joint structure between members constituting the vehicle body of an automobile, there is a T-shaped joint structure such as a joint structure of a side sill and a cross member shown in FIG. Since the vehicle body of an automobile is required to have the stability of the vehicle body during running, the bending rigidity related to the riding comfort, and the impact resistance to protect the occupants in the event of a collision, the T-shaped joint structure of the vehicle body as described above is used. It is desired to improve the bending rigidity and the impact resistance even in the above-mentioned place. In view of this requirement, Patent Document 1 discloses a T-shaped joint structure joined so as to connect the upper surface of the side sill and the upper surface of the cross member.

International Publication No. 2016/07635

FIG. 2 is a diagram showing a conventional T-shaped joint structure 50 in which the cross member 20 is brought into contact with the top plate portion 12a of the side sill 10, but the T-shaped joint structure of Patent Document 1 is the conventional T-shaped joint shown in FIG. Rigidity and impact resistance can be greatly improved with respect to the structure 50. However, while the vehicle body of an automobile is required to have improved rigidity and impact resistance, it is also required to reduce the weight of the vehicle body in order to improve fuel efficiency. From this point of view, the T-shaped joint structure of Patent Document 1 has a large increase in weight as compared with the conventional T-shaped joint structure 50, and therefore, there is room for further improvement from the viewpoint of weight reduction.

The present invention has been made in view of the above circumstances, and an object of the present invention is to ensure sufficient bending rigidity, impact resistance, and weight reduction in a T-shaped joint structure.

One aspect of the present invention for solving the above problems is a hollow member having a T-shaped joint structure having a first flat surface portion and a second flat surface portion which is a flat surface portion other than the first flat surface portion. A second member, which is a hollow member extending perpendicular to the longitudinal direction of the first member, which is fixed in contact with the first flat surface portion of the first member. The member and the reinforcing member provided inside the first member, and one end of the reinforcing member at both ends in the longitudinal direction of the second member is the first. When the other end is referred to as a second end, the first end of the reinforcing member is joined to the inner surface of the first flat surface of the first member. The second end of the reinforcing member is joined to the inner surface of the second flat surface of the first member, and is a portion between the first end and the second end. In a cross section perpendicular to the longitudinal direction of the first member, the midway portion is not in contact with the inner surface of the first member and is cut so as to include the hollow portion of the second member. The range of the portion where the first flat surface portion of the first member and the first end portion of the reinforcing member contact, and the first flat surface portion and the second member of the first member range of parts of contact, Ri least part Do heavy in direction perpendicular to the longitudinal direction of the second member in the vertical cross section, the shape of the middle portion in the vertical cross section, straight or curved It is characterized in that.

According to the present invention, in the T-shaped joint structure, sufficient bending rigidity, impact resistance can be ensured, and weight reduction can be achieved at the same time.

It is a figure which shows the body structure of a general automobile. It is a figure which shows the T-shaped joint structure of the conventional side sill and a cross member. It is a perspective view which shows the schematic structure of the T-shaped joint structure of the side sill and the cross member which concerns on embodiment of this invention. FIG. 3 is a perspective view when FIG. 3 is viewed from below. It is a figure which shows the cross section perpendicular to the longitudinal direction of a side sill which was cut so as to include the hollow part of a cross member in the T-shaped joint structure which concerns on embodiment of this invention. It is a figure which shows an example of the joining means of the side sill top plate part and the cross member top plate flange part. It is a top view of the T-shaped joint structure which concerns on another embodiment of this invention. FIG. 3 is a view showing a cross section perpendicular to the longitudinal direction of the side sill, which is cut so as to include a hollow portion of a cross member in the T-shaped joint structure according to another embodiment of the present invention. FIG. 3 is a view showing a cross section perpendicular to the longitudinal direction of the side sill, which is cut so as to include a hollow portion of a cross member in the T-shaped joint structure according to another embodiment of the present invention. It is a figure which shows the ladder frame of an automobile. It is a figure which shows the analysis model of a deformation simulation. It is a figure which shows the analysis model of a deformation simulation. FIG. 12 is a diagram showing a cross section perpendicular to the longitudinal direction of the side sill cut so as to include a hollow portion of the cross member in the analysis model shown in FIG. It is a figure which shows the displacement amount in the vehicle width direction at the position of the side sill top plate portion in the vehicle height direction. It is a figure for demonstrating the connection position in FIG. It is a figure which shows the bending rigidity of each analysis model in a deformation simulation. It is a figure which shows the analysis model of a collision simulation (A). It is a figure which shows the maximum load in each analysis model which the fiber direction of the reinforcing member made of CFRP is different. It is a figure which shows the absorption energy in each analysis model which the fiber direction of the reinforcing member made of CFRP is different. It is a figure which shows the maximum load in each analysis model which the thickness of a reinforcing member is different. It is a figure which shows the absorption energy in each analysis model which the thickness of a reinforcing member is different. It is a figure which shows the analysis model of a collision simulation (B). It is a figure which shows the maximum load in each analysis model which the fiber direction of the reinforcing member made of CFRP is different. It is a figure which shows the absorption energy in each analysis model which the fiber direction of the reinforcing member made of CFRP is different. It is a figure which shows the maximum load in each analysis model which the thickness of a reinforcing member is different. It is a figure which shows the absorption energy in each analysis model which the thickness of a reinforcing member is different. It is a figure which shows the analysis model of a collision simulation (C). It is a figure which shows the maximum load in each analysis model which the fiber direction of the reinforcing member made of CFRP is different. It is a figure which shows the absorption energy in each analysis model which the fiber direction of the reinforcing member made of CFRP is different. It is a figure which shows the maximum load in each analysis model which the thickness of a reinforcing member is different. It is a figure which shows the absorption energy in each analysis model which the thickness of a reinforcing member is different.

Hereinafter, embodiments of the present invention will be described with reference to the drawings. In the present specification and the drawings, the elements having substantially the same functional configuration are designated by the same reference numerals, so that duplicate description will be omitted.

In the present embodiment, an example of a joint structure of a side sill of an automobile and a cross member (floor cross member) will be described as a T-shaped joint structure. As shown in FIGS. 3 to 5, the T-shaped joint structure 1 of the present embodiment has a side sill 10 as an example of a first member, a cross member 20 as an example of a second member, and an inner side of the side sill 10. It is composed of the reinforcing member 30 provided in the above. The cross member 20 is joined to the side sill 10 in a state of being in contact with the side sill 10, and is fixed so as to extend perpendicular to the _{side sill longitudinal direction L 1.} In the present specification, the _{direction perpendicular to both the side sill longitudinal direction L 1} and the cross member longitudinal direction L ₂ is referred to as "height direction H". In the case of the joint structure of the side sill 10 and the cross member 20 as in the present embodiment, the side sill longitudinal direction L ₁ is the vehicle length direction, the cross member longitudinal direction L ₂ is the vehicle width direction, and the height direction H is the vehicle height direction.

In the side sill 10 of the present embodiment, a flat plate 11 is used as the outer member, _{and a member having a hat-shaped cross section perpendicular to the side sill longitudinal direction L 1} (hereinafter, “hat-shaped member 12”) is used as the inner member. Has been done. The hat-shaped member 12 has a top plate portion 12a, a vertical wall portion 12b extending perpendicularly to the top plate portion 12a from both ends of the top plate portion 12a in the height direction H, and a height from the tip portion of the vertical wall portion 12b. It has a flange portion (hereinafter, “hat flange portion 12c”) extending outward in the vertical direction H. The flat plate 11 and the hat flange portion 12c are joined by, for example, spot welding. The configurations of the outer member and the inner member of the side sill 10 are not limited to those described in this embodiment. For example, the outer member may be a hat-shaped member as well as the inner member. That is, the side sill 10 may be a hollow member having a hollow portion 10a.

In the cross member 20 of the present embodiment, a flat plate 21 is used as an outer member, and as an inner member, a member having a hat-shaped cross section perpendicular to _{the cross member longitudinal direction L 2 (hereinafter, “hat-shaped member 22”).} Is used. Hat member 22 includes a top plate portion 22a, and a vertical wall portion 22b which extends perpendicularly to the side sill longitudinal direction L ₁ of the top plate portion 22a from both ends of the top plate portion 22a, the distal end portion of the vertical wall portion 22b It has a flange portion (hereinafter, “hat flange portion 22c”) extending outward in the longitudinal direction L _{1 of the side sill.} The flat plate 21 and the hat flange portion 22c are joined by, for example, spot welding. The configurations of the outer member and the inner member of the cross member 20 are not limited to those described in this embodiment. For example, the outer member may be a hat-shaped member as well as the inner member. Further, the flat plate 21 may be a floor panel (not shown). In this case, a cross member 20 in which a hollow portion is formed by a part of the floor panel and a hat-shaped member is configured. That is, the cross member 20 may be a hollow member having a hollow portion 20a.

Of both ends of the cross member 20 in the longitudinal direction L _2, the end portion on the side that abuts on the side sill 10 (hereinafter, “contact side end portion 23”) is in the height direction from the top plate portion 22a of the cross member 20. A flange portion extending to H (hereinafter referred to as “top plate flange portion 23a”), a _{flange portion extending outward from the vertical wall portion 22b in the longitudinal direction L 1} of the side sill (hereinafter referred to as “vertical wall flange portion 23b”), and a flat plate 21. A flange portion (hereinafter, “flat plate flange portion 23c”) extending from the plate portion 21a in the longitudinal direction L _{2 of the cross member is formed.} The top plate flange portion 23a and the vertical wall flange portion 23b are joined by, for example, single-sided spot welding in a state of being in contact with the top plate portion 12a of the side sill 10. The flat plate flange portion 23c is joined by spot welding, for example, on one side of the side sill 10 in a state of being in contact with the vertical wall portion 12b on the outer side of the vehicle in the height direction H. By joining the top plate flange portion 23a, the vertical wall flange portion 23b, and the flat plate flange portion 23c to the side sill 10 in this way, the side sill 10 and the cross member 20 are fixed.

As shown in FIG. 5, one end (hereinafter, “first end 30a”) of both ends of the cross member longitudinal direction L _{2 of the plate-shaped reinforcing member 30 is the top plate portion 12a of the side sill 10.} The other end (hereinafter, "second end 30b") is joined to the inner surface of the upper vertical wall portion 12b of the side sill 10 in the height direction H. The position of the first end portion 30a in the height direction H is substantially the same as the position of the top plate flange portion 23a in the height direction H, and the top plate portion 12a of the side sill 10 is the reinforcing member 30. It is sandwiched between the first end portion 30a and the top plate flange portion 23a of the cross member 20. _{More specifically, in the cross section perpendicular to the side sill longitudinal direction L 1} cut so as to include the hollow portion 20a of the cross member 20, in the portion of the top plate portion 12a of the side sill 10 in contact with the first end portion 30a. The range of the height direction H (hereinafter, "contact range R ₁ ") and the range of the height direction H in the portion of the top plate portion 12a of the side sill 10 in contact with the top plate flange portion 23a (hereinafter, "contact range R"). ₂ ”) is partially overlapped. In other words, when the contact range R ₁ and the contact range R ₂ are viewed from the cross member longitudinal direction L _{2 , the lower portion of the contact range R 1} overlaps with the upper portion of the contact range R _2.

In the present embodiment, the intermediate portion 30c, which is a portion between the first end portion 30a and the second end portion 30b, is not joined to the inner surface of the side sill 10, and is in the height direction in the cross section shown in FIG. It is a straight line inclined with respect to H. The middle portion 30c has a shape along the inner surfaces of the top plate portion 12a and the vertical wall portion 12b of the side sill 10, and may be joined to the top plate portion 12a and the vertical wall portion 12b, respectively. With the shape of the middle portion 30c as in the form, it is possible to reduce the amount of material used for the reinforcing member 30 while ensuring sufficient bending rigidity and impact resistance, and it is possible to reduce the cost. Further, the intermediate portion 30c, as shown in examples described later, the shape in a cross section perpendicular to the side sill longitudinal direction L ₁ may be curved.

The method of joining the reinforcing member 30 to the inner surface of the side sill 10 is not particularly limited, but the reinforcing member 30 is joined by being attached to the inner surface of the side sill 10 using, for example, an adhesive. Therefore, when manufacturing the T-shaped joint structure 1 of the present embodiment, for example, after joining the reinforcing member 30 to the inner surface of the hat-shaped member 12 of the side sill 10, the hat-shaped member 12 and the flat plate 11 are spot-welded. The side sill 10 is manufactured. After that, the T-shaped joint structure 1 is manufactured by spot welding the cross member 20 in a state where the cross member 20 is abutted against the top plate portion 12a of the side sill 10. When an adhesive is used, it can be confirmed that the adhesive exists between the side sill 10 and the reinforcing member 30 by observing the cross section of the joint portion between the inner surface of the side sill 10 and the reinforcing member 30. can. When the reinforcing member 30 is made of, for example, CFRP (carbon fiber reinforced resin), the CFRP may be thermosetting, but is preferably thermoplastic from the viewpoint of moldability and adhesiveness. ..

The T-shaped joint structure 1 of the present embodiment is configured as described above. In the case of the conventional T-shaped joint structure, when the cross member 20 is bent in the height direction H (hereinafter, “vertical bending”), the top plate portion 12a of the side sill 10 follows the bending of the cross member 20. , Out-of-plane deformation is likely to occur at the portion where the top plate flange portion 23a comes into contact.

On the other hand, in the T-shaped joint structure 1 of the present embodiment, the first end portion 30a of the reinforcing member 30 is joined to the top plate portion 12a of the side sill 10, and the second end portion 30b is joined to the vertical wall portion 12b. ing. In this way, the first end portion 30a of the reinforcing member 30 is joined to the top plate portion 12a of the side sill 10, and the second end portion 30b of the reinforcing member 30 is a vertical wall portion which is a flat surface portion different from the top plate portion 12a. By being joined to 12b, the positional relationship between the top plate portion 12a and the vertical wall portion 12b can be easily maintained when the T-shaped joint structure 1 receives an external force. Then, when the cross member 20 is vertically bent, the reinforcing member 30 is stretched, so that the out-of-plane deformation of the top plate portion 12a is suppressed. As a result, the bending rigidity of the T-shaped joint structure 1 with respect to vertical bending can be improved. In addition to this, since the degree of out-of-plane deformation of the top plate portion 12a of the side sill 10 can be suppressed even during a side collision, the impact resistance of the T-shaped joint structure 1 can be improved.

Further, according to the T-shaped joint structure 1 of the present embodiment, the increase in weight with respect to the degree of improvement in bending rigidity and impact resistance against vertical bending is small, and the weight efficiency is improved from the viewpoint of bending rigidity and impact resistance against vertical bending. do. In other words, even when the thickness of the side sill 10 and the cross member 20 is reduced for weight reduction, sufficient bending rigidity and impact resistance can be ensured.

For example, when the lower end of the first end portion 30a of the reinforcing member 30 is higher than the upper end of the top plate flange portion 23a of the cross member 20, the top plate flange portion 23a of the top plate portion 12a is in contact with the top plate flange portion 23a. Out-of-plane deformation is likely to occur in the portion. Similarly, if the lower end of the first end portion 30a is located lower than the lower end of the top plate flange portion 23a, out-of-plane deformation is likely to occur at the portion of the top plate portion 12a in contact with the top plate flange portion 23a. Become. _{Therefore, in order to improve the bending rigidity and impact resistance of the T-shaped joint structure 1} , at least a part of the contact range R1 of the first end portion 30a in the top plate portion 12a of the side sill 10 is the top plate portion 12a. It is necessary to overlap with _{the contact range R 2} of the top plate flange portion 23a in the above. From the viewpoint of improving bending rigidity and impact resistance, it is preferable that the overlapping portion _{of the contact range R 1} and the contact range R _{2 becomes larger.}

Here, the length of the side sill longitudinal L ₁ of the reinforcing member 30 shown in FIG. 3 referred to as a "width W _a of the reinforcing member 30 ', side sill longitudinal L ₁ of the junction region between the side sill 10 and the top plate flange 23a The length of is referred to as the "joint area width W _b ". Width W _a of the reinforcing member 30, the bending rigidity or impact resistance is required, or is intended to be appropriately changed according to the weight limit and the like, it is preferable to satisfy W _b ≦ 1.5W _a. By satisfying this condition, the out-of-plane deformation of the top plate portion 12a of the side sill 10 can be further suppressed, and the bending rigidity and the impact resistance can be improved. When the top plate portion 12a of the side sill 10 and the top plate flange portion 23a of the cross member 20 are joined by spot welding as shown in FIG. 3, the width W _{b of the joining region is set to L 1} in the longitudinal direction of the side sill. It is the distance between the spot spots located at both ends of the spot spots lined up along the line. Further, the top plate portion 12a and the top plate flange portion 23a and is, for example, laser welding as shown in FIG. 6, the continuous welding arc welding or the like, or if it is joined with an adhesive, and the width W _b of the junction region, the weld region Alternatively, it is the length from one end to the other end of the side sill in the longitudinal direction L _{1 of the bonding region.} The thickness of the reinforcing member 30 is appropriately changed according to the required flexural rigidity or impact resistance, weight limitation, etc., but is preferably 1 to 5 mm, for example.

Further, when the reinforcing member 30 is made of, for example, CFRP, if the amount of the reinforcing member 30 is such that it is used for the T-shaped joint structure 1 as in the present embodiment, the parts to which the reinforcing member 30 is joined are melted as scrap. Even when it is reused, the impurities in the steel do not increase excessively. That is, the T-shaped joint structure 1 of the present embodiment is excellent in recyclability because it is not necessary to separate the side sill 10 and the reinforcing member 30 when the parts are reused as scrap.

Although the embodiments of the present invention have been described above, the present invention is not limited to such examples. It is clear that a person skilled in the art can come up with various modifications or modifications within the scope of the technical ideas described in the claims, and of course, the technical scope of the present invention also includes them. It is understood that it belongs to.

For example, the shape of the reinforcing member 30 is not limited to that described in the above embodiment. For example, as shown in FIG. 7, the second end portion 30b of the reinforcing member 30 may be V-shaped instead of linear in a plan view. By imparting a shape to the reinforcing member 30 in this way, the rigidity in the cross section of the side sill 10 can be increased, and as a result, the rigidity of the T-shaped joint structure 1 can be further increased. Further, the first end portion 30a and the middle portion 30c of the reinforcing member 30 may be provided with a shape for increasing the rigidity of the side sill 10.

In the above embodiment, the second end portion 30b of the reinforcing member 30 is joined to the inner surface of the vertical wall portion 12b on the upper side of the vertical wall portion 12b of the side sill 10 in the height direction H. As shown, it may be joined to the inner surface of the vertical wall portion 12b below the height direction H. Even in this case, the first end portion 30a of the reinforcing member 30 is joined to the top plate portion 12a of the side sill 10, and the second end portion 30b is joined to the vertical wall portion 12b which is a flat surface portion other than the top plate portion 12a. ing. Therefore, also in the case of the T-shaped joint structure 1 shown in FIG. 8, the positional relationship between the top plate portion 12a and the vertical wall portion 12b is easily maintained when an external force is applied, and the out-of-plane deformation of the top plate portion 12a is suppressed. It becomes possible.

Further, the second end portion 30b of the reinforcing member 30 may be joined to the inner surface of the flat plate 11 of the side sill 10 as shown in FIG. Even in this case, the first end portion 30a of the reinforcing member 30 is joined to the top plate portion 12a of the side sill 10, and the second end portion 30b is joined to the flat plate portion 11 which is a flat surface portion other than the top plate portion 12a. .. Also in the case of the T-shaped joint structure 1 shown in FIG. 9, the positional relationship between the top plate portion 12a and the flat plate 11 is easily maintained when an external force is applied, and it is possible to suppress the out-of-plane deformation of the top plate portion 12a. Become.

That is, if the second end portion 30b of the reinforcing member 30 is joined to a flat surface portion other than the flat surface portion to which the first end portion 30a is joined, the flexural rigidity and impact resistance of the T-shaped joint structure 1 Can be improved.

Further, as the type of the cross member 20 of the above embodiment, in addition to the floor cross member, the front cross member and the rear cross member joined to the side sill 10, the roof cloth joined to the roof side rail as shown in FIG. 1, for example. There are also members. Therefore, the T-shaped joint structure 1 may be, for example, a joint structure of a roof side rail and a roof cross member. When the T-shaped joint structure is a joint structure of a roof side rail and a roof cross member, the longitudinal direction of the roof side rail is the vehicle length direction, the longitudinal direction of the roof cross member is the vehicle width direction, and the height direction H is the vehicle height direction. .. Further, the T-shaped joint structure may be a T-shaped joint structure of another part included in the vehicle body structure of the automobile. For example, the T-shaped joint structure can also be adopted in a ladder frame as shown in FIG. Further, the T-shaped joint structure is not limited to the automobile field, and can be used as a T-shaped joint structure between members in other fields. Even in this case, as in the above embodiment, sufficient bending rigidity, impact resistance can be ensured, and weight reduction can be achieved at the same time.

Further, for example, if the side sill 10 and the cross member 20 described in the above embodiment are paraphrased by "first member" and "second member", the T-shaped joint structure is the first end portion of the reinforcing member 30. 30a is joined to the inner surface of the first flat surface portion (top plate portion 12a of the side sill 10 in the example of FIG. 5) of the first member, and the second end portion 30b of the reinforcing member 30 is other than the first flat surface portion. It can be said that the structure is joined to the inner surface of the second flat surface portion (the vertical wall portion 12b of the side sill 10 in the example of FIG. 5 and the flat plate 11 of the side sill 10 in the example of FIG. 9). Further, in order to improve the bending rigidity and the impact resistance, the first member is cut in a cross section perpendicular to _{the longitudinal direction L 1 of the first member, which is cut so as to include the hollow portion of the second member. The range R 1} in the height direction H of the portion where the first flat surface portion and the first end portion 30a of the reinforcing member 30 contact, and the portion where the first flat surface portion and the second member of the first member come into contact with each other. _{It is required that the range R 2} in the height direction H of is at least partially overlapped. When the T-shaped joint structure is a joint structure of the roof side rail and the roof cross member, the roof side rail is the first member and the roof cross member is the second member.

In the present specification, the "first flat surface portion" and the "second flat surface portion" of the first member are the hollow portion of the first member (example of FIG. 5) among the flat surface portions of the first member. Then, it means a flat surface portion constituting the hollow portion 10a) of the side sill 10. For example, when the first member is the side sill 10 as shown in FIG. 5, the hollow portion 10a is composed of the top plate portion 12a of the hat-shaped member 12, the vertical wall portion 12b, and the flat plate 11, and the hat flange portion 12c. Although it is a flat surface portion, it does not contribute to the configuration of the hollow portion 10a. Therefore, the hat flange portion 12c is not the first flat surface portion or the second flat surface portion in the present specification.

The material of the reinforcing member is not particularly limited. The reinforcing member may be a member made of FRP (fiber reinforced resin) such as a member made of CFRP (carbon fiber reinforced resin) or a member made of GFRP (glass fiber reinforced resin), for example. Further, the reinforcing member may be an aluminum alloy member, a magnesium alloy member, a steel material, or the like. Further, the reinforcing member may be a composite member made of the above-mentioned plurality of materials.

<Type of reinforcing member made of FRP>
The reinforcing member made of FRP means a fiber-reinforced resin member made of a matrix resin and a composite reinforcing fiber material contained in the matrix resin.

As the reinforcing fiber material, for example, carbon fiber or glass fiber can be used. In addition, boron fiber, silicon carbide fiber, aramid fiber and the like can be used as the reinforcing fiber material. In FRP, as the reinforcing fiber base material which is the base material of the reinforcing fiber material, for example, a non-woven fabric base material using chopped fiber, a cloth material using continuous fiber, a unidirectional reinforcing fiber base material (UD material), etc. are used. can do. These reinforcing fiber base materials can be appropriately selected depending on the orientation needs of the reinforcing fiber material.

The reinforcing member made of CFRP is a reinforcing member made of FRP using carbon fiber as a reinforcing fiber material. As the carbon fiber, for example, PAN-based or pitch-based carbon fibers can be used. By using carbon fiber, it is possible to efficiently improve the strength against weight and the like.

The reinforcing member made of GFRP is a reinforcing member made of FRP using glass fiber as a reinforcing fiber material. Although it is inferior in mechanical properties to carbon fiber, it can suppress electrolytic corrosion of metal members.

As the matrix resin used for the reinforcing member made of FRP, either a thermosetting resin or a thermoplastic resin can be used. Examples of the thermosetting resin include epoxy resin, unsaturated polyester resin, vinyl ester resin and the like. Examples of the thermoplastic resin include polyolefins (polyethylene, polypropylene, etc.) and acid-modified products thereof, polyamide resins such as nylon 6 and nylon 66, thermoplastic aromatic polyesters such as polyethylene terephthalate and polybutylene terephthalate, polycarbonate, and polyether sulfone. , Polyphenylene ether and its modified products, polyarylate, polyetherketone, polyetheretherketone, polyetherketoneketone, styrene resins such as vinyl chloride and polystyrene, and phenoxy resins. The matrix resin may be formed of a plurality of types of resin materials.

Considering application to metal members, it is preferable to use a thermoplastic resin as the matrix resin from the viewpoint of processability and productivity. Further, by using a phenoxy resin as the matrix resin, the density of the reinforcing fiber material can be increased. Further, since the phenoxy resin has a molecular structure very similar to that of the epoxy resin which is a thermosetting resin, it has the same heat resistance as the epoxy resin. Further, by further adding a curing component, it can be applied to a high temperature environment. When the curing component is added, the amount to be added may be appropriately determined in consideration of the impregnation property into the reinforcing fiber material, the brittleness of the reinforcing member made of FRP, the tact time, the processability and the like.

<Adhesive resin layer>
When the reinforcing member is formed of FRP or the like, an adhesive resin layer is provided between the reinforcing member made of FRP and the metal member (side sill 10 in the above embodiment), and the adhesive resin layer makes the reinforcing member made of FRP. It may be bonded to a metal member.

The type of the adhesive resin composition forming the adhesive resin layer is not particularly limited. For example, the adhesive resin composition may be either a thermosetting resin or a thermoplastic resin. The types of the thermosetting resin and the thermoplastic resin are not particularly limited. For example, the thermoplastic resin includes polyolefin and its acid modified product, polystyrene, polymethylmethacrylate, AS resin, ABS resin, thermoplastic aromatic polyester such as polyethylene terephthalate and polybutylene terephthalate, polycarbonate, polyimide, polyamide, and polyamide. Use one or more selected from imide, polyetherimide, polyethersulfone, polyphenylene ether and its modified products, polyphenylene sulfide, polyoxymethylene, polyarylate, polyetherketone, polyetheretherketone, polyetherketoneketone and the like. can do. Further, as the thermosetting resin, for example, one or more selected from epoxy resin, vinyl ester resin, phenol resin, and urethane resin can be used.

The adhesive resin composition can be appropriately selected depending on the characteristics of the matrix resin constituting the reinforcing member made of FRP, the characteristics of the reinforcing member, or the characteristics of the metal member. For example, by using a resin having a polar functional group or an acid-modified resin as the adhesive resin layer, the adhesiveness is improved.

As described above, by adhering the reinforcing member made of FRP to the metal member by using the above-mentioned adhesive resin layer, the adhesion between the reinforcing member made of FRP and the metal member can be improved. Then, when a load is input to the metal member, the deformation followability of the reinforcing member made of FRP can be improved. In this case, it is possible to more reliably exert the effect of the reinforcing member made of FRP on the deformed body of the metal member.

The form of the adhesive resin composition used for forming the adhesive resin layer can be, for example, a powder, a liquid such as varnish, or a solid such as a film.

Further, the crosslinkable adhesive resin composition may be formed by blending a crosslinkable curable resin and a crosslinking agent with the adhesive resin composition. As a result, the heat resistance of the adhesive resin composition is improved, so that it can be applied in a high temperature environment. As the crosslinkable curable resin, for example, a bifunctional or higher functional epoxy resin or a crystalline epoxy resin can be used. Further, as a cross-linking agent, an amine, an acid anhydride or the like can be used. Further, the adhesive resin composition may contain various additives such as various rubbers, inorganic fillers and solvents as long as the adhesiveness and physical characteristics are not impaired.

Composite of the reinforcing member made of FRP into a metal member is realized by various methods. For example, an FRP forming prepreg which is a reinforcing member made of FRP or a precursor thereof and a metal member are adhered with the above-mentioned adhesive resin composition, and the adhesive resin composition is solidified (or cured). Obtained at. In this case, for example, by performing heat crimping, the reinforcing member made of FRP and the metal member can be combined.

Adhesion of the above-mentioned FRP or FRP molding prepreg to a metal member may be carried out by appropriately selecting before, during or after molding the part, or by stepping each part as appropriate. For example, after molding a metal material to be processed into a metal member, FRP or a prepreg for FRP molding may be bonded to the metal member. Further, after the FRP or the prepreg for FRP molding is appropriately bonded to the work material by heat crimping, the work material to which the reinforcing member made of FRP is adhered is molded, and then the reinforcing member made of the FRP is separated. The portion may be adhered to the molded metal member to obtain a metal member composited with a reinforcing member made of FRP. If the matrix resin of the reinforcing member made of FRP is a thermoplastic resin, it is also possible to perform molding such as bending while controlling the temperature of the portion to which the reinforcing member made of FRP is adhered. Further, when the matrix resin of the reinforcing member made of FRP is a thermoplastic resin, composite batch molding in which the heat crimping step and the molding step are integrated may be performed.

The method of joining the reinforcing member made of FRP and the metal member is not limited to the above-mentioned bonding by the adhesive resin layer. For example, the reinforcing member made of FRP and the metal member may be mechanically joined. More specifically, holes for fastening are formed at corresponding positions of the reinforcing member made of FRP and the metal member, and these are fastened through the holes by fastening means such as bolts and rivets, whereby FRP. A reinforcing member made of and a metal member may be joined. In addition, a reinforcing member made of FRP and a metal member may be joined by a known joining means. Further, the reinforcing member made of FRP and the metal member may be joined in a composite manner by a plurality of joining means. For example, the bonding by the adhesive resin layer and the fastening by the fastening means may be used in combination.

Further, the reinforcing member may be formed by overlaying as an overlaying portion. In this case, the type of metal used for overlaying is appropriately determined in consideration of the characteristics of the metal member with the base metal. Further, the joining method with the metal member is not limited to welding, and various appropriate joining methods can be used.

<Metal parts and their surface treatment>
The metal member according to the present invention may be plated. This improves corrosion resistance. In particular, when the metal member is a steel material, it is more suitable. The type of plating is not particularly limited, and known plating can be used. For example, as plated steel sheets (steel materials), hot-dip galvanized steel sheets, hot-dip alloyed zinc-plated steel sheets, Zn-Al-Mg-based alloy-plated steel sheets, aluminum-plated steel sheets, electrogalvanized steel sheets, electric Zn-Ni-based alloy-plated steel sheets, etc. Can be used.

Further, the surface of the metal member may be coated with a film called chemical conversion treatment. This further improves the corrosion resistance. As the chemical conversion treatment, a generally known chemical conversion treatment can be used. For example, as the chemical conversion treatment, zinc phosphate treatment, chromate treatment, chromate-free treatment and the like can be used. Further, the film may be a known resin film.

Further, the metal member may be one having a generally known coating. This further improves the corrosion resistance. A known resin can be used for coating. For example, as the coating, a resin containing an epoxy resin, a urethane resin, an acrylic resin, a polyester resin, a fluororesin or the like as a main resin can be used. Further, generally known pigments may be added to the coating, if necessary. Further, the coating may be a clear coating to which no pigment is added. Such coating may be applied to the metal member in advance before the reinforcing member made of FRP is compounded, or may be applied to the metal member after the reinforcing member made of FRP is compounded. Further, the metal member may be previously painted, and then the reinforcing member made of FRP may be compounded and then painted. The paint used for painting may be a solvent-based paint, a water-based paint, a powder paint or the like. As a method of applying coating, a generally known method can be applied. For example, as a coating method, electrodeposition coating, spray coating, electrostatic coating, dip coating, or the like can be used. Electrodeposition coating is suitable for covering the end faces and gaps of metal members, and therefore has excellent corrosion resistance after coating. Further, by applying a generally known chemical conversion treatment such as zinc phosphate treatment or zirconia treatment to the surface of the metal member before painting, the adhesion to the coating film is improved.

<Deformation simulation>
In order to evaluate the flexural rigidity of the T-shaped joint structure according to the present invention, the analysis models shown in FIGS. 11 (1) and 12 (2) were created and deformation simulations were performed. Each analysis model is composed of a side sill 10, a cross member 20 joined to the top plate portion 12a of the side sill 10, and a reinforcing member 30 made of CFRP provided inside the side sill 10. The first end portion 30a of the reinforcing member 30 is joined to the inner surface of the top plate portion 12a of the side sill 10, and the second end portion 30b is joined to the upper vertical wall portion 12b of the side sill 10 in the height direction H. .. Further, in the analysis model shown in FIG. 11, the shape of the cross section of _{the reinforcing member 30 in the middle portion 30c perpendicular to the side sill longitudinal direction L 1 is linear.} In the analysis model shown in FIG. 12, the shape of the cross section of _{the reinforcing member 30 in the middle portion 30c perpendicular to the side sill longitudinal direction L 1 is curved as shown in FIG.} The width of the reinforcing member 30 is longer than the width of the top plate flange portion 23a of the cross member 20. In each of the following simulations including this simulation, the material of the side sill 10 and the cross member 20 is a 1.5 GPa class steel plate, the plate thickness of the side sill 10 is 0.8 mm, and the plate thickness of the cross member 20 is 1. It is 4 mm. The plate thickness of the reinforcing member 30 is 1.0 mm, and the fiber direction of the CFRP is parallel to the _{cross member longitudinal direction L 2.} The reinforcing member used has an elastic modulus of 131.5 GPa in the fiber direction and an elastic modulus of 8.5 GPa in the direction orthogonal to the fiber. The breaking stress in the fiber direction is 2490 MPa, and the breaking stress in the direction orthogonal to the fiber is 76 MPa.

In the deformation simulation, the cross sections of both ends of the side sill 10 in the longitudinal direction L _{1 are completely constrained.} Further, of both ends of the cross member 20 in the longitudinal direction L ₂ , the end portion on the side that does not abut on the side sill 10 (hereinafter, “non-contact side end portion”) is allowed to be displaced in the height direction H. , The in-plane deformation of the cross section is restrained so as not to occur. Under such constraint conditions, by inputting a downward load F (100N) in the height direction H to the non-contact side end of the cross member 20, a deformation simulation assuming vertical bending of the cross member 20 is carried out. bottom. As a comparative example, an analysis model of a conventional T-shaped joint structure in which no reinforcing member was provided was created for the analysis model of FIG. 11, and deformation simulation was performed under the same analysis conditions.

FIG. 14 shows the displacement amount _{in the vehicle width direction (cross member longitudinal direction L 2} ) at the position of the top plate portion 12a of the side sill 10 in the vehicle height direction as a result of the deformation simulation. The reference position of the vehicle height direction coordinates in FIG. 14 is the position of the R stop on the lower side of the top plate portion 12a of the side sill 10. Further, the “connection position” in FIG. 14 is a welding position between the top plate portion 12a of the side sill 10 and the top plate flange portion 23a of the cross member 20 as shown in FIG. As shown in FIG. 14, in the first and second embodiments provided with the reinforcing member, the out-of-plane deformation of the top plate portion 12a of the side sill 10 was smaller than that in the case where the reinforcing member was not provided.

In addition, Table 1 and FIG. 16 below show the flexural rigidity of each analysis model in this simulation.

※ＣＲＦＰ配向における０°方向はクロスメンバー２０の長手方向Ｌ₂に平行な方向である。

* The 0 ° direction in the CRFP orientation is the direction parallel to _{the longitudinal direction L 2 of the cross member 20.}

The "flexural rigidity" is the load (kN) per unit displacement (mm) generated in each analysis model, and shows the value when the result in the analysis model without reinforcement is 1. As shown in FIG. 16, in the first and second embodiments, the bending rigidity is improved by providing the reinforcing member. That is, in the T-shaped joint structure according to the present invention, the weight efficiency of the rigidity against vertical bending is greatly improved. Thereby, for example, even when the plate thickness of the side sill or the cross member is reduced for weight reduction, sufficient bending rigidity can be ensured according to the T-shaped joint structure according to the present invention. Therefore, according to the T-shaped joint structure according to the present invention, it is possible to secure sufficient bending rigidity and reduce the weight at the same time.

Next, in order to evaluate the impact resistance of the T-shaped joint structure according to the present invention, a collision simulation was carried out using the analysis model of Example 1. In the collision simulation, both ends of the side sill 10 in the longitudinal direction L ₁ are completely constrained.

<Collision simulation (A)>
The collision simulation (A) is a simulation simulating a pole side collision. As shown in FIG. 17, the collision simulation (A) was carried out by applying an impactor to the central portion of _{the flat plate 11 in the longitudinal direction L 1 of the side sill to which the cross member 20 abuts.} More specifically, the simulation was carried out by colliding an impactor having a diameter of 254 mm from the outside of the side sill 10 at 500 mm / s over the position on the center line of the cross member 20 and the total height of the side sill 10. Then, the impact resistance of the analysis model was evaluated by evaluating the maximum load (reaction force) and absorbed energy when the stroke of the impactor was 30 mm.

The analysis model shown in Table 2 below was created and simulated.

※ＣＲＦＰ配向における０°方向はクロスメンバー２０の長手方向Ｌ₂に平行な方向である。

* The 0 ° direction in the CRFP orientation is the direction parallel to _{the longitudinal direction L 2 of the cross member 20.}

As a simulation result, the maximum load in the analysis models of Examples 3 to 5 in which the CFRP orientations are different from each other is shown in FIG. 18, and the absorbed energy in the analysis models of Examples 3 to 5 is shown in FIG. As shown in FIGS. 18 and 19, the T-shaped joint structure according to the present invention has an increased maximum load and absorbed energy as compared with the conventional T-shaped joint structure in which no reinforcing member is provided.

As a simulation result, the maximum load in the analysis models of Examples 6 to 7 in which the plate thicknesses of the reinforcing members are different from each other is shown in FIG. 20, and the absorbed energy in the analysis models of Examples 6 to 7 is shown in FIG. As shown in FIGS. 20 and 21, the T-shaped joint structure according to the present invention has an increased maximum load and absorbed energy as compared with the conventional T-shaped joint structure in which no reinforcing member is provided.

<Collision simulation (B)>
The collision simulation (B) is a simulation simulating a pole side collision, but the position of the impactor is different from that of the above-mentioned collision simulation (A). As shown in FIG. 22, in the collision simulation (B), the impactor is applied to a position offset from the central portion of the flat plate 11 of the side sill 10 with which the cross member 20 abuts in the longitudinal direction L _{1 of the side sill.} More specifically, the simulation is carried out by colliding an impactor having a diameter of 254 mm from the outside of the side sill 10 at 500 mm / s at a position offset by 100 mm from the center line of the cross member 20 in the longitudinal direction L _{1 of the side sill and over the entire height of the side sill 10.} Was done. The analysis model is the model shown in Table 3 below.

※ＣＲＦＰ配向における０°方向はクロスメンバー２０の長手方向Ｌ₂に平行な方向である。

* The 0 ° direction in the CRFP orientation is the direction parallel to _{the longitudinal direction L 2 of the cross member 20.}

As a simulation result, FIG. 23 shows the maximum load in the analysis models of Examples 3 to 5 in which the CFRP orientations of the reinforcing members are different from each other, and FIG. 24 shows the absorbed energy in the analysis models of Examples 3 to 5. As shown in FIGS. 23 and 24, the T-shaped joint structure according to the present invention has an increased maximum load and absorbed energy as compared with the conventional T-shaped joint structure in which no reinforcing member is provided.

As a simulation result, FIG. 25 shows the maximum load in the analysis models of Examples 6 to 7 in which the plate thicknesses of the reinforcing members are different from each other, and FIG. 26 shows the absorbed energy in the analysis models of Examples 6 to 7. As shown in FIGS. 25 and 26, the T-shaped joint structure according to the present invention has an increased maximum load and absorbed energy as compared with the conventional T-shaped joint structure in which no reinforcing member is provided.

<Collision simulation (C)>
The collision simulation (C) is a simulation simulating a side collision between vehicles. As shown in FIG. 27, in the collision simulation (C), the position of the impactor is offset upward in the height direction H with respect to the above-mentioned collision simulation (A). More specifically, the simulation was carried out by colliding an impactor having a diameter of 254 mm from the outside of the side sill 10 with the position on the center line of the cross member 20 and the region of the upper half of the total height of the side sill 10 at 500 mm / s. The analysis model is the model shown in Table 4 below.

※ＣＲＦＰ配向における０°方向はクロスメンバー２０の長手方向Ｌ₂に平行な方向である。

* The 0 ° direction in the CRFP orientation is the direction parallel to _{the longitudinal direction L 2 of the cross member 20.}

As a simulation result, the maximum load in the analysis models of Examples 3 to 5 in which the CFRP orientations of the reinforcing members are different from each other is shown in FIG. 28, and the absorbed energy in the analysis models of Examples 3 to 5 is shown in FIG. As shown in FIGS. 28 and 29, the T-shaped joint structure according to the present invention has an increased maximum load and absorbed energy as compared with the conventional T-shaped joint structure in which no reinforcing member is provided.

As a simulation result, the maximum load in the analysis models of Examples 6 to 7 in which the plate thicknesses of the reinforcing members are different from each other is shown in FIG. 30, and the absorbed energy in the analysis models of Examples 6 to 7 is shown in FIG. As shown in FIGS. 30 and 31, the T-shaped joint structure according to the present invention has an increased maximum load and absorbed energy as compared with the conventional T-shaped joint structure in which no reinforcing member is provided.

When the relationship between the displacement of the impactor and the reaction force received by the impactor in this simulation was evaluated, the reaction force was large at the stage where the displacement of the impactor was small, that is, at the initial stage of deformation of the T-shaped joint structure. Therefore, it is considered that the out-of-plane deformation of the top plate portion of the side sill was suppressed at the initial stage of deformation, so that the reaction force became larger as compared with the conventional T-shaped joint structure and contributed to the improvement of the absorbed energy. Therefore, according to the T-shaped joint structure according to the present invention, sufficient impact resistance can be ensured.

Summarizing the results of the above deformation simulation and collision simulation, it was shown that the T-shaped joint structure according to the present invention can achieve both sufficient bending rigidity and impact resistance and weight reduction.

In the reinforcing member of the analysis model of Example 5, a CFRP layer in the fiber direction of 45 °, a CFRP layer in the −45 ° direction, a CFRP layer in the 90 ° direction, and a CFRP layer in the 0 ° direction are laminated. It is a member composed of four layers of CFRP. In the above-mentioned collision simulation, deformation progresses locally in various directions at the portion of the side sill where the impactor collides, but in the analysis model of Example 5, there are multiple layers of CFRP in different fiber directions. By doing so, it is possible to generate a reaction force not only with a load in one direction but also with a load in a plurality of directions. That is, in the analysis model of Example 5, since the deformation traveling in various directions can be suppressed, good results were obtained in any of the collision simulations (A) to (C). Such an effect can be obtained not only when the material of the reinforcing member is CFRP but also when it is FRP. Further, when the reinforcing member is made of FRP, the fiber direction of the FRP is preferably the so-called pseudoisotropic orientation as in the fifth embodiment, but if there are at least two fiber directions, one is used. It is possible to improve the impact resistance as compared with the case of the reinforcing member made of FRP only in the fiber direction. Therefore, when the reinforcing member is a member made of FRP, it is preferable that the reinforcing member has two or more fiber directions. The reinforcing member having two or more fiber directions may be formed by stacking layers of FRP having one fiber direction in different directions, or may be configured by stacking layers of FRP having one fiber direction in different directions, or may be formed by stacking layers of FRP having two or more fiber directions in different directions. It may be composed of linear fibers crossed and woven in the layer.

The present invention can be used, for example, in a joint structure of a side sill and a cross member of an automobile.

1 T-shaped joint structure 10 Side sill 10a Hollow part of side sill 11 Flat plate of side sill 12 Hat-shaped member of side sill 12a Top plate part 12b Vertical wall part 12c Hat flange part 20 Cross member 20a Hollow part of cross member 21 Flat plate of cross member 21a Flat plate Plate part 22 Cross member hat-shaped member 22a Top plate part 22b Vertical wall part 22c Hat flange part 23 Cross member contact side end part 23a Top plate flange part 23b Vertical wall flange part 23c Flat plate flange part 30 Reinforcing member 30a 1st end 30b of the member 30b 2nd end of the reinforcing member 30c Midway of the reinforcing member 50 Conventional T-shaped joint structure F Load H Height direction L ₁ Side sill longitudinal direction L ₂ Cross member longitudinal direction R ₁ Side sill Contact range of the first end of the _{top plate R 2} Contact range of the top plate flange on the top plate of the side sill W _a Width of the reinforcing member W _b Width of the top plate flange of the cross member

Claims (10)

It has a T-shaped joint structure and
A first member which is a hollow member having a first flat surface portion and a second flat surface portion which is a flat surface portion other than the first flat surface portion.
A second member, which is a hollow member extending perpendicularly to the longitudinal direction of the first member, which is fixed in contact with the first flat surface portion of the first member.
It has a reinforcing member provided inside the first member, and has.
When one end of the reinforcing member in the longitudinal direction of the second member is referred to as a first end and the other end is referred to as a second end, the reinforcing member is referred to as a second end.
The first end of the reinforcing member is joined to the inner surface of the first flat surface of the first member.
The second end of the reinforcing member is joined to the inner surface of the second flat surface of the first member.
The halfway portion, which is a portion between the first end portion and the second end portion, does not contact the inner surface of the first member.
In a cross section perpendicular to the longitudinal direction of the first member, which is cut so as to include a hollow portion of the second member, the first flat surface portion of the first member and the first surface portion of the reinforcing member. The range of the portion where the end portion of the first member contacts and the range of the portion where the first flat surface portion of the first member and the second member contact with each other are the longitudinal directions of the second member in the vertical cross section. Ri least part Do heavy in the direction perpendicular to the,
The shape of the middle portion in the vertical cross section is linear or curved. In the T-shaped joint structure according to claim 1,
The first member has a hat-shaped member and has a hat-shaped member.
The first flat surface portion is a top plate portion of the hat-shaped member.
The second flat surface portion is a vertical wall portion of the hat-shaped member. In the T-shaped joint structure according to claim 1 or 2,
The direction perpendicular to both the longitudinal direction of the first member and the longitudinal direction of the second member is referred to as a height direction.
Of both ends in the longitudinal direction of the second member, flange portions extending in the height direction are formed at the ends of the first member on the first flat surface side.
The flange portion of the second member and the first flat surface portion of the first member are joined to each other. In the T-shaped joint structure according to claim 3,
The second member has a hat-shaped member and has a hat-shaped member.
The flange portion of the second member is formed on the top plate portion of the hat-shaped member of the second member. In the T-shaped joint structure according to claim 3 or 4,
The width W _{a of the reinforcing member and the width W b} of the joint region between the first flat surface portion of the first member and the flange portion of the second member have W _b ≤ 1.5 W _a . Fulfill. In the T-shaped joint structure according to any one of claims 1 to 5,
The reinforcing member is a member made of at least one of FRP, an aluminum alloy, a magnesium alloy, and a steel material. In the T-shaped joint structure according to any one of claims 1 to 6, in the T-shaped joint structure.
The reinforcing member is a member made of FRP having two or more fiber directions. In the T-shaped joint structure according to claim 6 or 7.
The FRP is at least one of CFRP and GFRP. In the T-shaped joint structure according to any one of claims 1 to 8, in the T-shaped joint structure.
The first member is a side sill of an automobile, and the second member is a floor cross member of an automobile. In the T-shaped joint structure according to any one of claims 1 to 8, in the T-shaped joint structure.
The first member is a roof side rail of an automobile, and the second member is a roof cross member of an automobile.

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