JP4754257B2 - Vehicle front side frame - Google Patents

Description

  The present invention relates to a vehicle front side frame having a hollow closed cross-section formed by welding and joining flange portions formed by bending respective lateral edges of at least two panels long in the vehicle front-rear direction having a U-shaped cross section. About.

  In general, high rigidity is required for the front side frame of a vehicle in consideration of improvement in handling stability and reduction of vibration, etc., but in the case of a frontal collision, consideration is given to smooth deformation to gently absorb the impact. Need to design.

For example, in Japanese Patent Application Laid-Open No. 5-105110, an inner panel having a plurality of beads extending in the vertical direction at a predetermined pitch, and an outer panel that forms a closed cross-section together with the inner panel and includes a plurality of beads extending in the vertical direction. There is disclosed a front side member of a vehicle including an outer panel having a pitch substantially equal to that of the bead of the inner panel and a plurality of beads arranged at a half pitch with respect to the bead of the inner panel. The front side member of the vehicle further includes a reinforcement formed in a wave shape that is convex toward the bead at a portion corresponding to the bead of the inner panel and the outer panel in the closed cross section. With such a configuration, the reinforcement, the inner panel, and the outer panel are deformed while buffering each other, and as a result, the deformation load of the front side member increases, resulting in an increase in impact energy absorption capability.
Japanese Patent Laid-Open No. 5-105110

  However, the vehicle front side member according to Patent Document 1 described above must accurately maintain the positions of the beads formed on the inner panel and the outer panel, respectively, and it is required to improve component accuracy and workability. There is a problem that it is difficult to keep low. Further, the reinforce disposed in the internal closed cross section is required to have a processing accuracy of the waveform shape and an accuracy of the disposition position.

  The present invention has been made in view of the above circumstances, and it is possible to achieve both high rigidity and rigidity in consideration of improvement in driving stability and reduction of vibration and collision performance at the time of frontal collision at a simple and low cost. An object is to provide a front side frame of a vehicle.

The present invention is a frame in which a flange portion formed by bending a lateral edge of each of at least two panels having a U-shaped cross section and extending in the vehicle longitudinal direction is welded to form a hollow closed cross section. in front side frame of a vehicle having a body, to the flange portion of the at least one panel of the two panels, thereby forming a bead portion of the communicating freely waveform an interior and an exterior of the frame body, the bead portion There are formed, in the portion where the flange portion and the flange portion of the other panel of one of the panels described above is opposed, the frame of these two opposing grooves formed inside said frame body of the flange portion as a guide groove It is characterized by applying a bond from the inside of the main body .

  According to the front side frame of the vehicle according to the present invention, it is possible to achieve both high rigidity and rigidity in consideration of improvement of steering stability and reduction of vibration, and collision performance at the time of frontal collision, easily and at low cost. Become.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.
1 to 4 show an embodiment of the present invention, FIG. 1 is an explanatory side view of a front side frame of a vehicle, FIG. 2 is a II-II sectional view of FIG. 1, and FIG. 3 is a III-III section of FIG. FIG. 4 and FIG. 4 are graphs showing the relationship between the opening displacement of the flange and the load.

  In FIG. 1, reference numeral 1 denotes a front side frame of a vehicle. The front side frame 1 includes a frame main body 2 having a hollow closed cross section along an inner side of a wheel apron (not shown) constituting a side wall of an engine room. It extends backward from the front end side of the engine room and is fixed.

  On the rear end side of the frame main body 2, a curved portion 4 that is gently curved downward is formed slightly in front of the toe board 3. At the rear portion of the curved portion 4, the rear end edge of the upper surface portion 2 a of the frame main body 2 is formed. The toe board 3 is abutted and joined by welding.

  The left and right side surfaces 2b, 2b and the lower surface 2c of the frame body 2 extend rearward along the lower surface of the inclined surface 3a below the toe board 3, and the upper end edges of the left and right side surfaces 2b, 2b are inclined to the inclined surface 3a. It is welded. A box-shaped closed cross section is formed by the inclined surface 3a of the toe board 3 and the left and right side surfaces 2b, 2b and the lower surface 2c of the frame body 2, and the rear extension 5 of the frame body 2 is configured.

  On the other hand, reference numeral 6 denotes left and right floor frames which are welded and joined to a lower portion of a floor panel (not shown) to form a hollow box-shaped cross section in the front-rear direction. A bent portion 7 that is bent upward along the three inclined surfaces 3a is formed. The front portion of the bent portion 7 is welded and joined at the upper surface edge to the inclined surface 3 a and the front end portion is fitted to the rear end of the rear extension 5 of the frame body 2.

  In FIG. 1, reference numeral 8 denotes a front suspension cross member that supports a front suspension (not shown) fixed in the width direction to the lower surface portion 2 c of the frame body 2.

  As shown in FIG. 3, the frame body 2 is formed by welding and joining flange portions 13 and 14 formed by bending the lateral edges of the inner panel 11 and the outer panel 12 which are U-shaped in cross section and are long in the vehicle front-rear direction. Thus, a hollow closed section is formed.

  The flange portion 13 formed on the inner panel 11 is formed by simply bending the edge as it is, but the flange portion 14 formed on the outer panel 12 is behind the front suspension cross member 8 and In a portion of a length (for example, 30 cm to 40 cm: a range indicated by A in FIG. 1) set in advance from the rear end side, the inside of the frame main body 2 is provided on both sides of the upper surface portion 2a and the lower surface portion 2c. Corrugated bead portions 15 and 15 are formed so as to communicate with the outside.

  As shown in FIG. 2, the bead portion 15 is joined to the flange portion 13 of the inner panel 11 by spot welding at a portion in contact with the flange portion 13 of the inner panel 11.

  The bead portion 15 is formed, and a groove formed by facing the flange portions 13 and 14 is used as a guide groove in a portion where the flange portion 13 of the inner panel 11 and the flange portion 14 of the outer panel 12 are opposed to each other. In the process after the electrodeposition coating on the inside and the outside of the frame body 2 is completed, the bond 16 is applied using the work holes 3b formed in the toe board 3.

  This bond 16 is, for example, a thermosetting bond that is cured by being kept in a known 160 ° C. furnace environment for about 20 minutes. Therefore, in this embodiment, since the bond 16 is applied after electrodeposition coating, if the furnace temperature in the coating process is different, a bond suitable for that temperature may be selected.

  In addition, in connection with a manufacturing process, it can also join by the weld bond structure which apply | coats a bond before spot welding by a metal process. In this case, since the bond 16 is applied before the electrodeposition coating of the frame body 2, the effect as an air hole in the electrodeposition coating of the bead portion 15 is reduced.

  Thus, since the front side frame 1 of the vehicle according to the present embodiment is configured, during normal driving, the rigidity of the bead portion 15 is a force that acts on the vehicle body in the up and down, left and right, and torsion directions by the bond 16. In contrast, the steering stability is excellent, and vibration noise and the like are effectively reduced.

  In particular, since the bond 16 is applied to the grooves formed by the opposing flange portions 13 and 14 of the inner panel 11 and the outer panel 12, the rigidity of the bead portion 15 is maintained higher. That is, the present inventors jointed the flange portions of the outer panel and the inner panel only by spot welding (hereinafter referred to as sample 1), and solidified the adhesive between the flange portions in addition to spot welding. (Hereinafter referred to as “sample 2”) and the rigidity of the joint depending on the state of application of the adhesive separately from the spot welding and the adhesive solidified between each flange and groove (hereinafter referred to as “sample 3”) As a result of an experiment on how the temperature changes, as shown in FIG. 4, as shown in FIG. 4, the rigidity of the joint portion of each flange portion was higher in the order of sample 3, sample 2, and sample 1. In FIG. 4, the horizontal axis represents the opening displacement of each flange, and the vertical axis represents the load required for this opening displacement. Comparing sample 2 and sample 3, it has been experimentally proven that for the same aperture displacement, sample 3 must be loaded approximately 5 times more. As described above, it has been experimentally confirmed that the rigidity of the joint portion of each flange is dramatically improved by filling the groove between the members with the adhesive. Therefore, as described above, in the present invention, since the bond is applied to the groove formed by the opposing flange portions 13 and 14 of the inner panel 11 and the outer panel 12, the rigidity of the joint portion can be further improved.

  Further, at the time of the collision, the bond 16 that is weak against the impact force is peeled off from the bead portion 15, the rigidity of the bead portion 15 is weakened, and is deformed at the end of the frontal collision. For this reason, the front side frame 1 can absorb the impact gently and can be deformed smoothly, and has excellent collision performance.

  In the present embodiment, the bead portion 15 is formed on the flange portion 14 of the outer panel 12, but the bead portion 15 may be formed on the flange portion 13 of the inner panel 11, or The flange portions 13 and 14 of both the inner panel 11 and the outer panel 12 may be formed. Further, in the present embodiment, the bead portions 15 and 15 are formed on both sides of the upper surface portion 2a and the lower surface portion 2c of the frame body 2, but they are formed only on the upper surface portion 2a or only on the lower surface portion 2c. You may do it. Furthermore, the positions where the bead portions 15 are formed may be provided at different lengths and different parts. The formation of the bead portion 15 is appropriately selected according to required rigidity and collision performance through experiments, CAE (Computer-Aided Engineering), and the like.

Side view of the front side frame of the vehicle II-II sectional view of FIG. III-III sectional view of FIG. Graph showing the relationship between flange opening displacement and load

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Front side frame 2 Frame main body 2a Upper surface part 2c Lower surface part 3 Toe board 6 Floor frame 8 Front suspension cross member 11 Inner panel 12 Outer panel 13 Flange part 14 Flange part 15 Bead part 16 Bond

Claims (5)

A vehicle having a frame main body having a hollow closed cross-section formed by welding and joining flange portions formed by bending each lateral edge portion outwardly of at least two panels that are at least U-shaped in the vehicle longitudinal direction. In the front side frame of
To the flange portion of the at least one panel of the two panels, the interior and exterior of the frame body so as to form a bead portion of the communicating freely waveform, is the bead portion is formed on one of the panels the flange In the portion where the flange portion of the other panel is opposed to the flange portion of the other panel, a bond is applied from the inside of the frame body with a groove formed inside the frame body facing the two flange portions as a guide groove. The front side frame of the vehicle. The vehicle front side frame according to claim 1 , wherein the bead portion formed on the flange portion is formed on at least one of an upper surface and a lower surface of the frame body . The frame body is connected to a front suspension cross member that supports the front suspension,
3. The vehicle front side frame according to claim 1 , wherein the bead portion is formed rearward of the front suspension cross member . The vehicle front side frame according to any one of claims 1 to 3, wherein the bond application is performed after electrodeposition coating of the frame body . 5. The vehicle according to claim 1 , wherein one of the flange portions of the two panels forming the frame body has a straight shape without providing the corrugated bead . 6. Front side frame.

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