JP4983867B2 - Vehicle frame structure and vehicle frame manufacturing method - Google Patents

Description

  The present invention relates to a tubular vehicle frame structure that constitutes a part of a vehicle body and causes bending deformation due to a load acting upon a vehicle collision, and a vehicle frame manufacturing method.

  Conventionally, many tubular frame structures that form part of the vehicle body have been proposed to ensure high bending rigidity and reliably protect passengers in the passenger compartment even when a load is applied during a vehicle collision. Has been.

  For example, in the following Patent Document 1, a tubular side sill constituting a part of a vehicle body is disclosed in which a reinforcement is provided at a corner portion to form a plurality of closed cross-section portions with the inner panel. .

  In this reinforcement, irregularities are formed in the cross-sectional direction orthogonal to the longitudinal direction of the side sill, and the convex portion is coupled to the inner side of the corner portion of the inner panel.

  In the following Patent Document 1, the side sill provided with the reinforcement and the side sill not provided with the reinforcement are analyzed for bending resistance characteristics when bending deformation occurs, and both are compared and examined. . And based on the comparison result, it has shown that the side sill provided with reinforcement was able to exhibit higher bending resistance.

  As disclosed in the following Patent Document 1, by providing the reinforcement as described above at the corner portion of the frame, bending deformation when a collision load or the like is applied even without a thick reinforcing material is provided. Can be efficiently suppressed. That is, in this case, the value obtained by dividing the bending resistance by the total weight of the frame, so-called performance weight efficiency, can be increased, and as a result, the weight of the frame can be reduced.

  In recent years, from the viewpoint of environmental protection, there has been an increasing demand for improvement in fuel consumption, and various research and developments have been made on weight reduction of vehicle bodies in order to achieve this. For these reasons, each vehicle frame is also required to be lightweight and exhibit high bending resistance, and the above-mentioned performance weight efficiency is an extremely important factor in developing a vehicle frame. It has become.

  Patent Document 2 below discloses a side sill in which a plurality of hollow spaces extending in the longitudinal direction of the side sill are formed in a peripheral region including a corner portion of the inner panel.

  Even with such a configuration, as in the frame structure disclosed in Patent Document 1 below, it is possible to exhibit a higher bending resistance than a simple flat frame. In this case, since the hollow space is formed, it is possible to improve the bending resistance of the frame while reducing the weight of the entire frame.

  In Patent Document 3 below, the behavior when bending deformation occurs in the frame is analyzed to verify the bending deformation mechanism. As a result, when a load is applied to the frame, large out-of-plane deformation occurs in the corner portion on the surface side where the force in the compression direction acts and in the peripheral area (here, out-of-plane deformation is only on the surface). It has been found that bending deformation occurs in the frame by the occurrence of general three-dimensional deformation involving displacement in the thickness direction of the surface, not two-dimensional deformation in which displacement occurs.

  In the technology disclosed in Patent Document 3 below, from such a viewpoint, the corner portion and its peripheral region are formed thicker than others, thereby reducing the weight of the frame, The bending resistance is improved.

JP 2009-1113766 A JP-A-11-208521 JP 2008-68759 A

  By the way, as disclosed in Patent Documents 1 to 3, the vehicle frame is generally provided with at least one plate-shaped U-shaped member in cross section, and flanges projecting outward in cross section at both ends thereof. It is often formed in a tubular shape by joining the other plate-like member to the part.

  Therefore, the present inventor, in developing a vehicle frame, the case where a functional plate corresponding to the reinforcement of Patent Document 1 is provided in the frame body including the above-described U-shaped member in section, the bending thereof is performed. The drag characteristics were analyzed and examined.

  As a result of earnest research, the present inventor has devised the arrangement of the functional plate with respect to the flange portion of the U-shaped member in cross section, thereby improving the bending resistance characteristics in cooperation with the flange portion and the functional plate. I found it.

Also, looking at the prior art disclosed in the above Patent Documents 1 to 3, which, in bending deformation initial vehicle frame, merely intended to comprise a higher bending force. In fact, in protecting an occupant from an impact load generated during a vehicle collision or the like, it is important not only to increase the bending resistance in the initial stage of bending deformation but also to increase the load energy that can be absorbed in the middle stage of bending deformation. .

  In recent years, while improving the load energy absorption characteristics in the middle of bending deformation of the vehicle frame, it has been a challenge to improve the performance weight efficiency of the vehicle frame (a value obtained by dividing the load energy absorption amount by the total frame weight). Yes.

  The present invention includes a U-shaped member having a flange portion at both ends, and achieves high performance weight efficiency while improving bending resistance characteristics in the initial stage of bending deformation and absorbing load energy in the middle stage of bending deformation. It is an object of the present invention to provide a vehicle frame structure and a vehicle frame manufacturing method capable of achieving both improvement in characteristics.

The vehicle frame structure according to the present invention is a tubular frame structure that forms a part of a vehicle body and generates a bending deformation due to a load acting upon a vehicle collision, with two U-shaped members facing each other. Or a frame main body formed in a tubular shape by connecting a U-shaped member and a flat plate-shaped member to each other and connecting both ends thereof, and the U-shaped member having a U-shaped cross section , A side surface portion that is continuous on both sides of the central surface portion, and a flange portion that protrudes outward in cross section at both end portions, and the flange portions or the flange portion and both end portions of the flat plate member are coupled to each other. The frame body has a first surface portion on which a force in the compression direction acts when the load is applied, and a second surface portion on which a force in the tensile direction acts, and the first and second surface portions. In between, at least one in front Is arranged the side portion of the shaped member cross section U, the said side surface portion includes a base portion spaced from the frame body, a plurality of function boards and the convex portion is integrated type formed with projecting from the base portion, The functional plate is coupled to the first surface portion, and a flat portion provided on the convex portion of the functional plate is coupled to the inner periphery of the side surface portion, and the convex portion is arranged in the longitudinal direction of the frame. A plurality of arrays are arranged in an orthogonal cross-sectional direction orthogonal to the longitudinal direction, and the functional plate is sandwiched at one end side between the flange portions or between the flange portions and the end portions of the flat plate-like members. The convex portions are formed so as to be periodically arranged in the longitudinal direction and the orthogonal cross-sectional direction, and the convex portions adjacent to each other in the longitudinal direction of the frame are orthogonal to each other. With cross-sectional overlap The convex portions adjacent to the orthogonal cross-sectional direction is to have the longitudinal overlap each other.

According to this configuration, the end surface of the functional plate is sandwiched between the flange portion of the frame main body or between the flange portion and the end portion of the flat plate-like member, so that the surface in the bent portion at the initial stage of bending deformation is obtained. External deformation can be more effectively suppressed by the cooperation of the frame body and the functional plate, and the bending resistance characteristics can be improved.
When the vehicle frame is bent and deformed, the side surface portion and the functional plate contribute to absorption of load energy over a wide range around the bent portion. Thereby, the load energy absorption characteristic of the vehicle frame in the middle of bending deformation can be improved.
Further, in this case, since the bending resistance characteristics and load energy absorption characteristics of the vehicle frame can be improved while suppressing the increase in the thickness of the frame body and the functional plate, the performance weight in the bending resistance characteristics and load energy absorption characteristics can be improved. Efficiency (bending resistance of vehicle frame / total weight of vehicle frame, absorbed amount of load energy / total weight of vehicle frame) can be improved.

  In addition, the convex portions adjacent to each other in the longitudinal direction of the frame have an overlap in the orthogonal sectional direction, and the convex portions adjacent to each other in the orthogonal sectional direction have an overlapping in the longitudinal direction. Therefore, in the longitudinal direction and the orthogonal cross-sectional direction, a linearly continuous base is not formed. For this reason, when a load is applied to the vehicle frame, it is possible to prevent the formation of folds (triggers for folding) in the longitudinal direction and the orthogonal cross-sectional direction of the base, and the folds promote out-of-plane deformation at the bent portions. Can be prevented.

  In one embodiment of the present invention, the first surface portion of the frame main body is formed by the central surface portion of the U-shaped cross-sectional member, and a corner portion is formed between the central surface portion and the side surface portion. The functional plate is provided in a region including the corner portion.

  According to this configuration, the out-of-plane deformation in the bent portion at the initial stage of bending deformation can be more effectively suppressed, and as a result, the bending resistance characteristic of the vehicle frame can be further improved.

  In one embodiment of the present invention, the convex portion has a polygonal frustum shape in which a tip portion coupled to the frame main body has a polygonal plane portion.

According to this configuration, when the convex portion is coupled to the frame main body by welding, the flat portion of the convex portion can be used as a welding allowance, and thereby the two can be more stably coupled.

  In one embodiment of the present invention, the convex portion has a truncated cone shape in which a tip portion coupled to the frame body has a circular plane portion.

  According to this configuration, since a larger gap is formed between the convex portions than in the case of the truncated pyramid shape, by forming the base portion in the gap, a structure constituted by the frame body and the functional plate The rigidity of can be improved. For this reason, the out-of-plane deformation in the bent portion at the initial stage of bending deformation can be more reliably suppressed.

According to the vehicle frame manufacturing method of the present invention, a plurality of convex portions protruding from the base are formed so as to be periodically arranged in the longitudinal direction of the frame and the orthogonal cross-sectional direction orthogonal to the longitudinal direction. A functional plate in which the adjacent convex portions overlap each other in the orthogonal cross-sectional direction and the convex portions adjacent to each other in the orthogonal cross-sectional direction overlap each other in the longitudinal direction. Preliminarily coupling to the inner periphery of the central surface portion of the U-shaped member and preliminarily coupling the flat surface portion provided on the convex portion to the inner periphery of the side surface portion continuous on both sides of the central surface portion; And a step of joining one end side of the functional plate to a flange portion formed at both end portions of the other U-shaped member, or an end portion of a flat plate-like member. It is.

  According to this configuration, the performance weight efficiency in the bending drag characteristics and the load energy absorption characteristics is improved, and further, when a load is applied to the vehicle frame, creases (triggers for folding) are generated in the longitudinal direction of the base and in the orthogonal cross-section direction. In manufacturing a vehicle frame that can be prevented from being formed and can prevent the out-of-plane deformation at the bent portion from being promoted by the crease, the convex portion of the functional plate can be easily framed using a known method. It can be combined with the body circumference.

According to the present invention, the one end side of the functional plate is sandwiched between the flange portion of the frame body or between the flange portion and the end portion of the flat plate-like member, so that the surface in the bent portion at the initial stage of bending deformation External deformation can be more effectively suppressed by the cooperation of the frame body and the functional plate, and the bending resistance characteristics can be improved. And at the time of bending deformation of the vehicle frame, the load energy absorption characteristic of the vehicle frame in the middle of bending deformation can be improved.
Further, in this case, since the bending resistance characteristics and load energy absorption characteristics of the vehicle frame can be improved while suppressing the increase in the thickness of the frame body and the functional plate, the performance weight in the bending resistance characteristics and load energy absorption characteristics can be improved. Efficiency (bending resistance of vehicle frame / total weight of vehicle frame, absorbed amount of load energy / total weight of vehicle frame) can be improved.
In addition, when a load is applied to the vehicle frame, it is possible to prevent the formation of folds (triggers for folding) in the longitudinal direction and the orthogonal cross-sectional direction of the base, and the folds promote out-of-plane deformation at the bent portions. Can be prevented.

  In addition, the performance weight efficiency in the bending drag characteristics and the load energy absorption characteristics is improved, and further, when a load is applied to the vehicle frame, a crease (folding trigger) is formed in the longitudinal direction of the base and in the orthogonal cross-section direction. In manufacturing a vehicle frame that can prevent the out-of-plane deformation at the bent portion from being promoted by the crease, the convex portion of the functional plate can be easily coupled to the inner periphery of the frame body by a known method. can do.

The perspective view which shows the frame structure for vehicles which concerns on 1st Embodiment of this invention. Sectional drawing when cut | disconnecting the frame for vehicles in the orthogonal cross-section direction orthogonal to a longitudinal direction. The front view for demonstrating the arrangement | sequence of each convex part of a function board. (A) The figure for demonstrating the analysis method of the bending drag characteristic of a vehicle frame, and a load energy absorption characteristic, (b) The perspective view which shows the curved state of a vehicle frame. The graph which shows the relationship between the reaction force with respect to this load when a load is added to the vehicle frame and the descending stroke of the indenter, and the relationship between the load energy absorption amount and the descending stroke of the indenter. The perspective view which shows the result of having analyzed the behavior of the frame for vehicles when a load is added from the orthogonal cross-section direction upper direction toward the center part of the 1st surface part of the frame for vehicles. The perspective view which shows the result of having carried out the simulation analysis of the behavior of a functional board. Sectional drawing which shows the shape of the closed cross section in a bending part. Sectional drawing for demonstrating the function of the structure comprised by the frame main body and the function board. The disassembled perspective view for demonstrating the manufacturing method of the flame | frame for vehicles. The disassembled perspective view for demonstrating the manufacturing method of the flame | frame for vehicles. The disassembled perspective view for demonstrating the manufacturing method of the flame | frame for vehicles. Sectional drawing for demonstrating the manufacturing method of the flame | frame for vehicles. The perspective view which shows the frame structure for vehicles which concerns on 2nd Embodiment of this invention. The disassembled perspective view for demonstrating the manufacturing method of the flame | frame for vehicles. The disassembled perspective view for demonstrating the manufacturing method of the flame | frame for vehicles. The disassembled perspective view for demonstrating the manufacturing method of the flame | frame for vehicles. Sectional drawing for demonstrating the manufacturing method of the flame | frame for vehicles. The perspective view which shows the frame structure for vehicles which concerns on 3rd Embodiment of this invention. The front view for demonstrating the arrangement | sequence of each convex part of a function board. The perspective view which shows the frame structure for vehicles which concerns on 4th Embodiment of this invention. The perspective view which shows the frame structure for vehicles which concerns on 5th Embodiment of this invention. The front view for demonstrating the arrangement | sequence of each convex part of a function board.

Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.
(First embodiment)
First, the first embodiment shown in FIGS. 1 to 13 will be described. FIG. 1 is a perspective view showing a vehicle frame structure according to the first embodiment of the present invention, and FIG. 2 is a cross-sectional view when the vehicle frame 1 is cut in an orthogonal cross-sectional direction orthogonal to the longitudinal direction. . As shown in FIG. 1, a vehicle frame 1 according to the present embodiment includes a frame main body 11 that includes first and second panel members 11A and 11B and includes first to fourth surface portions 11a to 11d, and a vehicle frame. 1 and two functional plates 12 extending in the longitudinal direction. In FIG. 1, for convenience of illustration, the frame body 11 is shown in a transmissive state while indicated by a one-dot chain line.

  Each of the first and second panel members 11A and 11B has a U-shaped shape in an orthogonal cross-sectional direction orthogonal to the longitudinal direction, and the first and second surface portions (center surface portions) 11a and 11b, 1, side surface portions 11c1, 11d1, 11c2, and 11d2 that are continuous on both sides of the second surface portions 11a and 11b, and flange portions 11i and 11j that protrude outward in cross-section at each end portion are formed.

  These two first and second panel members 11A and 11B are opposed to each other, and the flange portions 11i and 11j located at both ends thereof are coupled to each other to form a rectangular tubular frame body 11.

  Here, when the first and second panel members 11A and 11B are joined, the side surface portions 11c1, 11d1, 11c2, and 11d2 are disposed between the first and second surface portions 11a and 11b. A third surface portion 11c is formed by a combination of the side surface portion 11c1 of the first panel member 11A and the side surface portion 11c2 of the second panel member 11B, and the side surface portion 11d1 of the first panel member 11A and the side surface of the second panel member 11B. A fourth surface portion 11d is formed by a combination with the portion 11d2.

  And corner part 11e-11h is formed between the 1st-4th surface parts 11a-11d. Among these, the function board 12 is arrange | positioned in the area | region of the inner peripheral side containing the corner parts 11e and 11f between the 1st surface part 11a and the 3rd, 4th surface parts 11c and 11d.

The functional plate 12 extends over substantially the entire length in the longitudinal direction of the vehicle frame 1, and in the orthogonal cross-sectional direction, the corner portions 11e and 11f, the side surface portions 11c1 and 11d1, and the flange portion 11i of the first panel member 11A, 11j. Then, a part of the function plate 12 includes a base portion 12a spaced from the frame body 11, a plurality of protrusions 12b having a planar portion 1 2 c on the tip protrudes from the base portion 12a are integrally formed.

  In addition, planar flange portions 12d and 12e are formed on the functional plate 12 at both ends in the orthogonal cross-section direction. In the function plate 12, the planar portion 12c of each convex portion 12b is coupled to the third and fourth surface portions 11b and 11c in the vicinity of the corner portions 11e and 11f. The flange portion 12d is coupled to the first surface portion 11a of the frame body 11, while the flange portion 12e is coupled in a state of being sandwiched between the flange portions 11i and 11j.

  FIG. 3 is a front view for explaining the arrangement of the convex portions 12 b of the functional plate 12. As shown in FIGS. 1 and 3, each of the convex portions 12b, 12b,... Of the functional plate 12 has a truncated pyramid shape in which the flat portion 12c forms a quadrangle, and the longitudinal direction and the orthogonal cross-sectional direction of the vehicle frame 1 Are periodically arranged.

  Furthermore, in the present embodiment, when attention is paid to one convex portion 12b, as shown in FIG. 3, this convex portion 12b overlaps with the convex portion 12b1 (12b2) adjacent in the longitudinal direction in the cross-sectional direction perpendicular to each other. And has a convex portion 12b2 (12b1) adjacent to each other in the orthogonal cross-sectional direction and an overlap L2 in the longitudinal direction.

  By arranging the convex portions 12b, 12b1, 12b2,... In such a positional relationship periodically, the base portion 12a that is linearly continuous is not formed in the longitudinal direction and the orthogonal cross-sectional direction. .

Next, with reference to FIGS. 4-9, by applying a load to the vehicle frame 1, the bending force characteristics when folded it, and the load energy absorbing characteristics will be described.
In developing the vehicle frame 1 as shown in FIG. 1, the present inventor conducted a simulation analysis on the behavior when a load F accompanied by bending deformation was added thereto by CAE (Computer Aided Engineering).

  FIG. 4A is a diagram for explaining a method of analyzing the bending drag characteristics and load energy absorption characteristics of the vehicle frame 1. In this analysis, as shown in FIG. 4A, a vehicle frame 1 having a predetermined length L is supported by fixed points X and X separated by a predetermined distance D shorter than the length L. It is assumed that the indenter Y is lowered from above at the center O located in the middle in the longitudinal direction of the fixed points X and X, and a load F corresponding to the load at the time of the vehicle collision is added. In FIG. 4, the upper surface is set to the first surface portion 11a, and a load F is applied to the surface of the first surface portion 11a from above in the orthogonal cross-sectional direction.

When the load F is applied, the maximum load that can be applied before the vehicle frame 1 is bent (herein referred to as the maximum load F ′ _max ) and the load energy that can be absorbed by the bending (here, the load energy). The maximum load F ′ _max and the load energy absorption amount were used as references for evaluating the superiority or inferiority of the bending drag characteristic and the load energy absorption characteristic, respectively.

  By the way, when a long tubular body like the vehicle frame 1 is bent, first, as shown in FIG. And when it will be in a curved state in this way, while it receives the force of a compression direction from the longitudinal direction both ends on the inner peripheral side of bending, it receives the force of the tensile direction from both ends of a longitudinal direction on the outer peripheral side of bending. In the case of FIG. 4, the inner peripheral side of the bending, that is, the side receiving the force in the compression direction is the first surface portion 11a, and the outer peripheral side of the bending, that is, the side receiving the force in the tensile direction is the second surface portion 11b.

  FIG. 5 shows the relationship between the reaction force F ′ against the load F when the load F is applied to the vehicle frame 1 and the descending stroke of the indenter Y, and the relationship between the load energy absorption amount and the descending stroke of the indenter Y. It is a graph which shows. In the simulation shown in FIG. 4, the inventor applied a load F to the central portion O, and then the reaction force F ′ of the vehicle frame 1 generated against the load F, and the bending and bending of the vehicle frame 1. The relationship with the position of the indenter Y that changes with this (this is called the downward stroke) was graphed.

  In FIG. 5, a peak appears in the value of the reaction force F ′ while the descending stroke of the indenter Y increases, and thereafter, the value of the reaction force F ′ gradually decreases as the descending stroke increases. It shows the tendency to do.

  Thus, in the graph shown in FIG. 5, when the load F is gradually increased in the curved state of the vehicle frame 1, the reaction force F ′ gradually increases as the load F increases before the above-described peak occurs. It shows that it is getting bigger. On the other hand, after the peak occurs, the rapid progress of the bending has already started in the vehicle frame 1, indicating that the reaction force F ′ against the load F has decreased due to the progress of the bending.

Here, the peak value of the reaction force F ′ shown in FIG. 5 indicates the maximum load F ′ _max that can be applied until the bending proceeds rapidly, and this maximum load F ′ _max is the degree of bending resistance. Is a numerical value representing

Further, in the graph shown in FIG. 5, the load energy (load energy absorption) that can be absorbed by the bending of the vehicle frame 1 by the area _{SEA of} the region surrounded by the coordinate axis of the descending stroke of the indenter Y and the graph of the reaction force F ′. Amount). In FIG. 5, the relationship between the descending stroke of the indenter Y and the area _SEA is also graphed.

  Next, the behavior when the load F is applied to the vehicle frame 1 and bent is described with reference to the simulation analysis results shown in FIGS. FIG. 6 is a perspective view showing a result of a simulation analysis of the behavior of the vehicle frame 1 when a load F is applied from above in the orthogonal cross-section direction toward the central portion O of the first surface portion 11a of the vehicle frame 1. FIG. 7 is a perspective view showing the result of simulation analysis of the behavior of the functional plate 12, and FIG. 8 is a cross-sectional view showing the shape of the closed cross section at the bent portion. Here, in FIG. 6, the process of bending deformation of the vehicle frame 1 is shown in the order of FIGS. 7A, 7B and 7C, and FIGS. 7A to 7C and FIG. In a) to (c), these correspond to FIGS. 6 (a) to (c), respectively. In FIGS. 6 and 7, the magnitude of the deformation amount of each part is indicated by the shade of the color, and the greater the deformation amount, the darker the color.

  The present inventor evaluates the bending drag characteristics and load energy absorption characteristics of the vehicle frame 1 shown in FIG. 1 when the load F as shown in FIG. 4A is added thereto. The deformation amount of each part was calculated.

  6 to 8, immediately after the load F is applied to the vehicle frame 1, a bent portion appears in the central portion O on which the load F acts, and the out-of-plane deformation mainly occurs at the bent portion. You can see that it has occurred. For example, in the bent portion, the first surface portion 11a to which the load F directly acts and the corner portions 11e and 11f and the flange portions 11i and 11j at both ends thereof are recessed, and the third and fourth surface portions 11c and 11d are outward in cross section. Is deformed out of plane (see the deformed portion α in the figure).

  Simultaneously with the out-of-plane deformation of the frame body 11, a bent portion appears in the functional plate 12 as shown in FIG. 7, and the out-of-plane deformation occurs there (see the deformation portion β in the figure).

  However, in the vehicle frame 1 of the present embodiment, the vertices P (see FIG. 8) of the corner portions 11e and 11f are suppressed from being greatly displaced outward, and further, the third and fourth surface portions 11c and 11d Significant out-of-plane deformation facing the cross section is suppressed.

  And especially when FIG. 8 is seen, in the second surface part 11b opposite to the first surface part 11a, a dent inward in the cross section is newly generated as the out-of-plane deformation of the corner parts 11e, 11f and the like is suppressed. Yes.

  Here, from the analysis results shown in FIG. 6 to FIG. 8, the inventor determines that the flange portion 12 e at one end of the functional plate 12 and the flange portions 11 i and 11 j of the frame body 11 are in the bent portion at the initial stage of bending deformation. It was found that out-of-plane deformation was suppressed. 6 to 8, the flange portions 11i, 11j, and 12e prevent the apex P of the corner portions 11e and 11f from being greatly displaced outward, and further, the cross sections of the third and fourth surface portions 11c and 11d. Outward large out-of-plane deformation is suppressed.

  In this embodiment, the flange portion 12e of the functional plate 12 is sandwiched between the flange portions 11i and 11j of the frame main body 11 so that the connection between the frame main body 11 and the functional plate 12 is strong. Thus, the out-of-plane deformation at the bent portion is more effectively suppressed by the cooperation of the both.

  In this way, by connecting one end side of the functional plate 12 between the flange portions 11i and 11j of the frame main body 11, the out-of-plane deformation at the bent portion at the initial stage of the bending deformation can be reduced. It can suppress more effectively by cooperation with 12, and can improve a bending drag characteristic.

For this reason, the maximum load F ′ _max shown in FIG. 5 can be increased as indicated by a two-dot chain line in the drawing, and as a result, the bending deformation until the bending deformation of the vehicle frame 1 rapidly proceeds ( The bending drag characteristics in FIG. 5) can be improved.

  Further, in the present embodiment, as shown in FIG. 9, the structure body 13 having a plurality of closed cross sections 13 a is formed not only in the orthogonal cross section direction of the vehicle frame 1 but also in the longitudinal direction by the frame main body 11 and the functional plate 12. It is formed in the direction. And in this structure 13, the frame main body 11 and the base part 12a are spaced apart from the neutral axis (surface) NA, and it has the structure where the cross-sectional secondary moment was raised.

Here, when an out-of-plane deformation occurs in the bent portion, deformation as shown in FIG. 9 occurs in the longitudinal direction and the orthogonal cross-sectional direction in the structure 13 at a position corresponding to the bent portion. Due to the high moment of inertia of the section in the body 13 , a high bending drag is exerted.

  From the analysis results shown in FIGS. 6 to 8, the inventor suppresses the out-of-plane deformation in the bent portion by the structure 13 having an increased secondary moment when the out-of-plane deformation occurs in the bent portion. I found out that I can do it.

  Furthermore, by connecting the plurality of convex portions 12b to the frame body 11, a plurality of virtual regions 13A (see hatched portions in FIG. 3) partitioned by lines connecting the connecting portions are formed in the structure 13. . The inventor has received the load F at each coupling point for each virtual region 13A by the cooperation of the frame body 11 and the functional plate 12, thereby suppressing the out-of-plane deformation at the bent portion more effectively. I found out.

  Further, since the out-of-plane deformation is also generated in the second surface portion 11b, the load is applied to the second surface portion 11b receiving the force in the tensile direction as much as the out-of-plane deformation in the corner portions 11e and 11f and its periphery is suppressed. It has been found that F can be received, and as a result, the bending resistance in the entire closed section of the bent portion is improved.

  As described above, the functional plate 12 having the plurality of convex portions 12b formed in the region including the corner portions 11e and 11f of the first surface portion 11a that receives the force in the compression direction when the frame body 11 is bent and deformed is disposed. By arranging the convex portions 12b in the longitudinal direction and the orthogonal cross-sectional direction of the vehicle frame 1, out-of-plane deformation in the bent portion at the initial stage of bending deformation can be more effectively suppressed.

In addition, the present inventor has the third and fourth in the middle of bending deformation (see FIG. 5) in which bending deformation of the vehicle frame 1 proceeds after the peak of the reaction force F ′ (maximum load F ′ _max ) occurs. It has been found that the surface portions 11c and 11d and the functional plate 12 are deformed substantially uniformly for each coupling portion around the bent portion.

In this case, the third and fourth surface portions 11c and 11d and the functional plate 12 are spread over a wide area around the bent portion by coupling the plurality of convex portions 12b to the third and fourth surface portions 11c and 11d. This contributes to energy absorption of the load F. As a result, the area _SEA in the middle of bending deformation can be increased, and the load energy absorption characteristics of the vehicle frame 1 can be improved.

In this case, the bending resistance characteristic and the load energy absorption characteristic can be improved because the bending resistance characteristic and the load energy absorption characteristic of the vehicle frame 1 can be improved while suppressing the increase in thickness of the frame body 11 and the functional plate 12. Performance weight efficiency (maximum load F ′ _max / total weight of vehicle frame 1, area S _EA / total weight of vehicle frame 1) can be improved.

  In addition, as shown in FIG. 3, one convex portion 12 b has an overlap L1 in the orthogonal cross-sectional direction with that adjacent in the longitudinal direction, and has an overlap L2 in the longitudinal direction with an adjacent one in the orthogonal cross-sectional direction. Thus, when the load F acts on the vehicle frame 1 by forming the base portion 12a that is linearly continuous in the longitudinal direction and the orthogonal cross-sectional direction, a crease is formed in the longitudinal direction and the orthogonal cross-sectional direction of the base portion 12a. It is possible to prevent the occurrence of (folding trigger) and promote out-of-plane deformation at the bent portion.

  Further, since the function plate 12 is formed with the flange portion 12d that is coupled to the first surface portion 11a that receives a force in the compression direction when the bending deformation occurs, the function plate 12 is detached from the frame body 11 when the vehicle frame 1 is bent. Peeling can be reliably prevented. For this reason, the out-of-plane deformation suppressing function and the load energy absorption increasing function of the structure 13 constituted by the frame main body 11 and the functional plate 12 can be further stabilized.

  In addition, since the convex portion 12b coupled to the frame body 11 has a quadrangular pyramid shape having a quadrangular plane portion, when the convex portion 12b is coupled to the frame main body 11 by welding, the convex portion 12b. The flat portion 12c can be used as a welding allowance, whereby the coupling between the two can be performed more stably.

Next, a method for manufacturing the vehicle frame 1 according to the present embodiment will be described with reference to FIGS.
First, the two functional plates 12 and 12 are coupled to the first panel member 11A shown in FIG. Specifically, as shown in FIG. 10, the inner periphery of the first surface portion 11a of the first panel member 11A and the flange portion 12d of the functional plate 12, and the flange portion 11i and the flange portion 12e are opposed to each other so that they overlap each other. The functional plate 12 is brought into contact with the first panel member 11A.

And the 1st surface part 11a inner periphery and the flange part 12d are couple | bonded by the coupling | bond part Z1 shown by a thick continuous line in FIG. 11, and both side surface part 11c1, 11d1 of 11 A of 1st panel members, and each convex of the functional board 12 The flat portion 12c of the portion 12b is joined by a coupling portion Z2 indicated by an x mark in FIG. At this time, the connection between the inner periphery of the first surface portion 11a and the flange portion 12d is performed by spot welding or laser welding along the longitudinal direction of both, and the connection between the side surface portions 11c1 and 11d1 and the flat surface portion 12c of the convex portion 12b. Is performed by spot welding.

  Next, the second panel member 11B is further coupled to the component generated by coupling the first panel member 11A and the functional plates 12 and 12. Specifically, as shown in FIG. 11, the flange portion 11j of the second panel member 11B is opposed to the portion where the flange portion 11i of the first panel member 11A and the flange portion 12e of the functional plate 12 are overlapped. And as shown in FIG. 12, the 2nd panel member 11B is contact | abutted to the said component, aligning so that each flange part 11i, 11j, 12e may overlap.

  Then, the three overlapping flange portions 11i, 11j, and 12e are polymerized and bonded by a thick solid line in FIG. 12 or a connecting portion Z3 indicated by a cross in FIG. Thereby, the frame main body 11 which makes | forms a rectangular tubular shape is formed, and the vehicle frame 1 provided with the functional board 12 is completed. At this time, the flanges 11i, 11j, and 12e are joined by spot welding or laser welding along their longitudinal directions.

  Thus, in this embodiment, when manufacturing the vehicle frame 1, the step of connecting the functional plate 12 to the inner periphery of the first panel member 11A in advance by the convex portion 12b and the flange portions 11i and 12e are connected to the second panel. And the step of polymerizing and bonding to the flange portion 11j of the member 11B, so that the convex portion 12b of the functional plate 12 can be easily coupled to the inner periphery of the frame body 11 using a known method such as spot welding or laser welding. Can do.

  When the functional plate 12 is coupled to the first panel member 11A, first, the inner periphery of the first surface portion 11a and the flange portion 11d are coupled, and then the side surface portions 11c1, 11d1 and the convex portion 12b are coupled. May be. In this case, the coupling portion Z1 serves as a temporary fastening when the side surface portions 11c1, 11d1 and the convex portion 12b are coupled.

  In the present embodiment, the flange portions 11i, 11j, and 12e are polymerized and bonded by one-time welding. However, the present invention is not necessarily limited to this. For example, in the step of joining the first panel member 11A and the functional plate 12 before joining the second panel member 11B to the component, the flange portion 11i and the flange portion 12e are joined in advance, and then the flange portion 11j. And the flange portion 12e may be coupled.

  Moreover, although each member was joined by welding, it is not necessarily limited to this, For example, you may join using an adhesive agent.

(Second Embodiment)
By the way, in the present invention, as in the vehicle frame 2 shown in FIG. 14, the frame main body 21 is composed of the first panel member 21 </ b> A having a U-shaped shape in the orthogonal cross-section direction and the plate-like second panel member 21 </ b> B. And one end side of the functional plate 22 may be sandwiched and coupled between the flange portion 21i and the end portion of the second panel member 21B.

  The first panel member 21A is formed with flange portions 21i and 21i projecting outward in cross section at both ends thereof. The first panel member 21A and the second panel member 21B are opposed to each other, and the flange portions 21i, 21i, A rectangular tubular frame body 21 is formed by joining both end portions of 21i and the second panel member 21B.

  In the present embodiment, in the first panel member 21A, a first surface portion (center surface portion) 21a, third and fourth surface portions (side surface portions) 21c, 21d continuous on both sides thereof, and a flange portion 21i are formed. Corner portions 21e and 21f are formed between the first surface portion 21a and the third and fourth surface portions 21c and 21d.

  Further, in the second panel member 21B, a second surface portion 21b is formed, and corner portions 21g and 21h are formed by coupling the first and second panel members 21A and 21B. Here, when the first and second panel members 21A and 21B are joined, the third and fourth surface portions 21c and 21d are disposed between the first and second surface portions 21a and 21b.

  In the present embodiment, the two functional plates 22 extend from the corner portions 21e and 21f to the corner portions 21g and 21h in the vertical cross-sectional direction, and cover the inner surfaces of the third and fourth surface portions 21c and 21d. Yes.

  The functional plate 22 is formed with a base portion 22a spaced from the frame body 21 and the third and fourth surface portions 21c and 21d, and a plurality of truncated pyramid-shaped convex portions 22b protruding from the base portion 22a.

  The functional plate 22 is formed with planar flange portions 22d and 22e at both ends in the orthogonal cross-section direction. In the function plate 22, the flat surface portion 22c of each convex portion 22b is coupled to the third and fourth surface portions 21c and 21d. The flange portion 22d is coupled to the first surface portion 21a of the frame main body 21, while the flange portion 22e is coupled in a state of being sandwiched between the flange portions 22i and 22j.

Next, a method for manufacturing the vehicle frame 1 according to the present embodiment will be described with reference to FIGS. 15 to 18.
First, the two functional plates 22 and 22 are coupled to the first panel member 21A shown in FIG. Specifically, as shown in FIG. 15, the inner periphery of the first surface portion 21a of the first panel member 21A and the flange portion 22d of the functional plate 22, and the flange portion 21i and the flange portion 22e are opposed to each other so as to overlap each other. The functional plate 22 is brought into contact with the first panel member 21A.

Then, the inner periphery of the first surface portion 21a and the flange portion 22d are coupled by a coupling portion Z4 indicated by a thick solid line in FIG. 16, and the third and fourth surface portions 21c, 21d of the first panel member 21A and the functional plate The flat surface portion 22c of each of the convex portions 22b of 22 is joined by a coupling portion Z5 indicated by a cross in FIG. At this time, the connection between the inner periphery of the first surface portion 21a and the flange portion 22d is performed by spot welding or laser welding, and the connection between the third and fourth surface portions 21c, 21d and the flat surface portion 22c of the convex portion 22b is both It is performed by spot welding along the longitudinal direction.

  Next, the second panel member 21B is further coupled to the component generated by coupling the first panel member 21A and the functional plates 22 and 22. Specifically, as shown in FIG. 16, both end portions of the second panel member 21B are opposed to a portion where the flange portion 21i of the first panel member 21A and the flange portion 22e of the functional plate 22 are overlapped. Then, as shown in FIG. 17, the second panel member 21B is brought into contact with the component while aligning the flanges 21i and 22e and the end of the second panel member 21B so as to overlap each other. Let

  Then, the three overlapping flange portions 21i and 22e and the end portions of the second panel member 21B are overlap-bonded by a connecting portion Z6 indicated by a thick solid line in FIG. 17 or an X mark in FIG. Thereby, the frame main body 21 which makes a rectangular tubular shape is formed, and the vehicle frame 2 including the functional plate 22 is completed. At this time, the flange portions 21i and 22e and the end portions are joined by spot welding or laser welding along their longitudinal directions.

  Thus, in this embodiment, when manufacturing the vehicle frame 2, the step of connecting the functional plate 22 to the inner periphery of the first panel member 21A with the convex portion 22b in advance, and the flange portions 21i and 22e are connected to the second panel. By having the step of polymerizing and bonding to both ends of the member 21B, the convex portion 22b of the functional plate 22 can be easily coupled to the inner periphery of the frame body 21.

  Also in this embodiment, the flange portions 21i and 22e and the end portions of the second panel member 21B are not necessarily limited to the polymerization bonding by one welding, and the second panel is not necessarily limited to this. Before joining the member 21B, the flange portion 21i and the flange portion 22e may be joined in advance, and then the end portion of the second panel member 21B and the flange portion 22e may be joined.

(Third embodiment)
In each embodiment described above, the convex portion of the functional panel is formed on anything Re also truncated pyramid, the present invention is not necessarily limited thereto. For example, like the functional plate 22 ′ of the vehicle frame 2 ′ shown in FIG. 19, the convex portion 32 b may be formed in a truncated cone shape so that the flat portion 32 c forms a circle. In FIG. 19, the same components as those of the second embodiment shown in FIG.

  In the present embodiment, the majority of the functional plate 22 ′ is a truncated cone-shaped protrusion 32 b, but the truncated pyramid-shaped protrusion 22 b is formed for one line in the longitudinal direction. In this case, the convex portion 22b is coupled by welding, while the convex portion 32b is coupled by, for example, an adhesive as a method other than welding.

  Also in this embodiment, as shown in FIG. 20, the convex portions 32b, 32b,... Overlap with one convex portion 32b adjacent to the longitudinal direction in the orthogonal cross-sectional direction and are orthogonal to each other. A base portion 32a that overlaps in the longitudinal direction with those adjacent to each other in the cross-sectional direction and is linearly continuous in the longitudinal direction and the vertical cross-sectional direction is not formed.

  By using the truncated cone-shaped convex portions 32b as in this embodiment, a larger gap is formed between the convex portions 32b as shown in FIG. 20 than in the case of a truncated pyramid shape. Here, if the base portion 32a is formed in the gap, when the structure body 13 is formed by the frame main body 21 and the functional plate 22 ′, the rigidity of the structure body 13 is obtained by having a flat portion on the base portion 32a side. Can be improved. Thereby, the out-of-plane deformation in the bent portion at the initial stage of bending deformation can be more effectively suppressed.

  In addition, what is necessary is just to select suitably whether the shape of the plane part of a convex part is polygonal or circular according to the coupling | bonding method to the frame main body of a convex part, the degree of rigidity required for the structure 13, etc. .

(Fourth embodiment)
By the way, this invention is not necessarily limited to forming both the base part and convex part of a functional board in the area | region containing the corner part of a frame main body. In the present invention, it is only necessary that the base portion and the convex portion are formed corresponding to at least the third and fourth surface portions of the frame main body. For example, as in the vehicle frame 4 shown in FIG. 21, the convex portion 42 b of the functional plate 42 may be configured not to reach the corner portions 41 e and 41 f of the frame main body 41.

  In the present embodiment, the frame main body 41 includes, as in the second and third embodiments, a first panel member 41A having a U-shaped cross-sectional shape, and a flat second panel member 41B. It is comprised by. In the frame main body 41, the parts of the frame main body 41 indicated by reference numerals 41a to 41d are first to fourth surface portions, respectively, 41e to 41h are corner portions, and 41i is a flange portion. In the functional plate 42, reference numeral 42a is a base, 42c is a flat surface, and 42d and 42e are flanges.

  In addition, in this embodiment, although the convex part 42b is formed in the truncated cone shape, you may form in a polygonal frustum shape, what was formed in the truncated cone shape, and what was formed in the polygonal truncated cone shape. May be juxtaposed.

(Fifth embodiment)
Moreover, in this invention, the shape of the plane part of a convex part is not necessarily limited to making it a polygon and a circle. For example, as in the vehicle frame 4 ′ shown in FIG. 22, the flat portion 52c of the convex portion 52b of the functional plate 42 ′ may be formed in a cross shape. In FIG. 22, the same components as those in the fourth embodiment shown in FIG.

  Also in this embodiment, as shown in FIG. 23, each convex portion 52b, 52b,... Overlaps with one convex portion 52b adjacent to the longitudinal direction in the orthogonal cross-sectional direction, It has a structure in which the adjacent base portions 52a are overlapped in the longitudinal direction with those adjacent to each other in the orthogonal cross-sectional direction, and no linearly continuous base portion 52a is formed in the longitudinal direction and the orthogonal cross-sectional direction.

(Other embodiments)
In each of the above-described embodiments, the functional plate includes a flange portion coupled to the first surface portion of the frame main body. However, depending on the position of the convex portion, the positional relationship with the corner portion and the reason for processing technology Therefore, it may be difficult to form the flange portion. In such a case, only the flange portion coupled to the flange portion of the frame main body may be provided in the functional plate.

In correspondence between the configuration of the present invention and the above-described embodiment,
The U-shaped members of the present invention correspond to the first panel members 11A, 21A, 41A,
Similarly,
The flat plate member corresponds to the second panel members 21B and 41B,
The present invention is not limited only to the configuration of the above-described embodiment, and many embodiments can be obtained.

1, 2, 2 ', 4, 4' ... Vehicle frames 11, 21, 41 ... Frame bodies 11A, 21A, 41A ... First panel members 11B, 21B, 41B ... Second panel members 11a, 21a, 41a ... No. 1st surface part 11b, 21b, 41b ... 2nd surface part 11c, 21c, 41c ... 3rd surface part 11d, 21d, 41d ... 4th surface part 11e, 11f, 21e, 21f, 41e, 41f ... Corner part 11i, 11j, 21i, 41i ... Flange portions 12, 22, 22 ', 42, 42' ... functional plates 12a, 22a, 32a, 42a, 52a ... base portions 12b, 22b, 32b, 42b, 52b ... convex portions
12c, 22c, 32c, 42c, 52c ... Planar portions 12e, 22e, 32e, 42e ... Flange portions L1, L2 ... Overlapping

Claims (5)

A tubular frame structure that constitutes a part of the vehicle body and causes a bending deformation due to a load acting upon collision of the vehicle,
A frame main body formed in a tubular shape by facing two U-shaped members in cross section or by facing both U-shaped members and a flat plate-shaped member, and connecting both ends thereof;
The U-shaped cross-sectional member is formed with a central surface portion, side surface portions that are continuous on both sides of the central surface portion, and flange portions that project outward at the both end portions,
The flange portions, or the flange portions and both end portions of the flat plate member are combined,
The frame body has a first surface portion on which a force in the compression direction acts when the load acts;
A second surface portion on which a force in the tensile direction acts,
Between the first and second surface portions, at least one side surface portion of the U-shaped cross-section member is disposed,
The side portion includes a base portion spaced from the frame body,
Comprising a plurality of functional plates and the projections are integrated type formed with projecting from the base portion,
The functional plate is coupled to the first surface portion, and a planar portion provided on the convex portion of the functional plate is coupled to the inner periphery of the side surface portion,
A plurality of the convex portions are arranged in the longitudinal direction of the frame,
A plurality of orthogonal cross-sectional directions orthogonal to the longitudinal direction,
The functional plate is coupled with one end side sandwiched between the flange portions or between the flange portion and the end of the flat plate member,
The convex portions are formed to be periodically arranged in the longitudinal direction and the orthogonal cross-sectional direction,
The convex portions adjacent to each other in the longitudinal direction of the frame have an overlap in the orthogonal cross-sectional direction, and
The vehicle frame structure in which the convex portions adjacent to each other in the orthogonal cross-sectional direction overlap each other in the longitudinal direction. Forming a first surface portion of the frame body by a central surface portion of the U-shaped cross-section member;
A corner portion is formed between the central surface portion and the side surface portion,
The vehicle frame structure according to claim 1, wherein the functional plate is provided in a region including the corner portion. 3. The vehicle frame structure according to claim 1, wherein the convex portion has a polygonal frustum shape in which a tip portion coupled to the frame body has a polygonal plane portion. 3. The vehicle frame structure according to claim 1, wherein the convex portion has a truncated cone shape in which a tip portion coupled to the frame body has a circular plane portion. A plurality of protrusions protruding from the base are formed so as to be periodically arranged in the longitudinal direction of the frame and the orthogonal cross-sectional direction orthogonal to the longitudinal direction,
The convex portions adjacent to each other in the longitudinal direction of the frame have an overlap in the orthogonal cross-sectional direction, and
The convex portions adjacent to each other in the orthogonal cross-section direction are joined in advance to the inner periphery of the central surface portion of the U-shaped member having a cross-section of the U-shaped cross section and continuous on both sides of the central surface portion. Preliminarily connecting a flat surface portion provided on the convex portion to the inner periphery of the side surface portion ;
The flange portion formed at both ends of the U-shaped member in the cross section and the one end side of the functional plate at the flange portion formed at both ends of the other U-shaped member in the cross section, or the end of the flat plate member A method for manufacturing a vehicle frame comprising the steps of combining.