JP2015006845A - Cross member structure of vehicle body - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a cross member structure of a vehicle body which enhances the rigidity of a cross member by a simple constitution, and can improve the rigidity of the vehicle body without causing an increase of weight and cost.SOLUTION: A cross member structure 100 of a vehicle body comprises a floor panel 104, a pair of side members 106, and a cross member 108 which is bridged to a pair of the side members 106. A cross section viewed from a vehicle width direction of the cross member 108 has a hat shape which is protruded to a lower part from the floor panel 104. The cross member 108 includes a center region E1 located in the center of the vehicle width direction, and two outside-expanded regions E2, E3 which further extend to the outside of the vehicle width direction from both ends of the center region E1, and have portions which are larger in the hat-shaped protrusion amounts than the center region E1. When viewing the cross member 108 from below, two shape change lines L1, L2 being change points of the hat-shaped protrusion amounts are oblique with respect to the vehicle fore-and-aft direction, and formed in non-parallel with each other.

Description

  The present invention relates to a vehicle body cross member structure including a floor panel, a pair of side members extending in the vehicle front-rear direction along each of the vehicle width direction ends of the floor panel, and a cross member inserted between the pair of side members. is there.

  The floor portion of the vehicle is an important part in securing the vehicle body rigidity. The floor portion of a normal vehicle has a configuration in which a plate-like floor panel, which is a floor material, is reinforced with side members and cross members. The side members are provided so as to extend in the vehicle front-rear direction along the side edges of the floor panel near the side edges in the vehicle width direction on the lower surface side of the floor panel. The cross member is provided so as to extend between the side members so as to extend in the vehicle width direction on the lower surface side of the floor panel.

  For example, as described in Patent Document 1, the cross member has a cross-sectional hat shape (hereinafter, simply “hat shape”) protruding downward from the floor panel. Further, the cross member has a structure that is divided into a central region (central region) in the vehicle width direction and an outer region (outer region) in the vehicle width direction. Comparing these central region and outer region, the outer region is set to have a larger amount of hat-shaped protrusion from the floor panel than the central region for connection with the side members.

JP 2011-240822 A

  The cross member supports the torsional rigidity of the vehicle body during traveling by supporting the floor panel in the vehicle width direction. Such a cross member is required to have a structure that suppresses deformation so that it can withstand a load in a bending direction or a twisting direction. However, as described above, the cross member differs in the amount of protrusion from the floor panel in the central region and the outer region. At the boundary between the central region and the outer region and the starting point of the change in the protruding amount, the load tends to collect and tends to be deformed.

  SUMMARY OF THE INVENTION The present invention has been made in view of the above problems, and an object of the present invention is to provide a vehicle body cross member structure capable of improving the rigidity of a cross member with a simple configuration and improving the vehicle body rigidity without causing an increase in weight or cost.

  In order to solve the above-described problems, a representative configuration of the vehicle body cross member structure according to the present invention includes a floor panel constituting the floor of the vehicle body, and both ends of the floor panel in the vehicle width direction provided on the lower surface side of the floor panel. A pair of side members extending in the vehicle front-rear direction, and a cross member inserted between the pair of side members and supporting the floor panel over the vehicle width direction. The cross member has a central region located in the center in the vehicle width direction, and further extends outward from the both ends of the central region in the vehicle width direction, and has a larger protrusion amount than the central region. Two outer extension regions each having a portion, and when the cross member is viewed from below, two shape deformations that are the starting points of the change in the amount of protrusion of the hat shape. Line, both a slant with respect to the vehicle longitudinal direction, characterized in that it is non-parallel to each other.

  In the cross member, two shape change lines provided at the lower end are oblique to the vehicle front-rear direction and are not parallel to each other. In other words, the two shape change lines are non-parallel to each other, so that the directions in which they are easily deformed are different. Therefore, when a load in a predetermined direction is applied to the cross member, even if the load is in a direction that is easily deformed for one shape change line, the direction is difficult to deform for the other shape change line. As described above, the cross member has enhanced bending rigidity due to the shape of the lower end portion thereof, and can exhibit high durability against loads in the bending direction and torsional direction while the vehicle is running. Yes. Moreover, in the said structure, since rigidity is improved by the device of a shape, compared with the case where an additional member is used, neither a weight increase nor a cost increase is caused, and it is suitable.

  The vehicle body cross member structure may further include a trailing arm type suspension that supports a tire with a trailing arm, and the trailing arm may be connected to the side member over the front and rear portions of the side member. In this configuration, since the trailing arm is connected to a portion of the side member where the rigidity is enhanced by the cross member, it is possible to more efficiently absorb the load, vibration, and the like transmitted from the tire.

  The center region and the outer extension region of the cross member are independent parts, and the center region has a hat-shaped lower end portion, a front wall portion, and a rear wall at an end portion connected to the outer extension region. It is good to have a brace that connects the part diagonally. By providing this bracing surface, the cross member has high rigidity between the lower end portion and the front wall portion and the rear wall portion. Therefore, it is possible to contribute to further improvement of the vehicle body rigidity.

  The vehicle body cross member structure further includes a spare tire storage portion that is formed by a floor panel projecting downward in the vicinity of the rear of the cross member and that stores a spare tire, and a cross member that connects the cross member and the spare tire storage portion. And a cross member center reinforcement that reinforces. If it is this structure, it will become possible to further improve the rigidity with respect to the bending direction or the twist direction of a cross member by supporting a cross member in a spare tire storage part via a cross member center reinforcement.

  ADVANTAGE OF THE INVENTION According to this invention, the rigidity of a cross member can be improved by simple structure, and the vehicle body cross member structure which can improve vehicle body rigidity without causing a weight increase and cost increase can be provided.

It is the figure which showed the outline | summary of the vehicle body cross member structure concerning embodiment of this invention. It is an arrow A figure of FIG. FIG. 2 is a perspective view showing a cross member under the suspension of FIG. It is an arrow B figure of FIG. It is the figure which illustrated the cross member of FIG. 3 independently from each direction. It is the figure which illustrated the cross member of Fig.5 (a) from another direction.

  Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings. The dimensions, materials, and other specific numerical values shown in the embodiments are merely examples for facilitating understanding of the invention, and do not limit the present invention unless otherwise specified. In the present specification and drawings, elements having substantially the same function and configuration are denoted by the same reference numerals, and redundant description is omitted, and elements not directly related to the present invention are not illustrated. To do.

  FIG. 1 is a view showing an outline of a vehicle body cross member structure 100 according to an embodiment of the present invention. FIG. 1 schematically illustrates the back side of the vehicle body 102. In FIG. 1, the front of the vehicle corresponds to the lower side in the figure, and the rear of the vehicle corresponds to the upper side in the figure. The left and right sides of the vehicle coincide with the left and right sides in the figure.

  As a main component of the vehicle body cross member structure 100, first, the floor panel 104 is cited. The floor panel 104 is a panel member that constitutes the floor of the vehicle body. The floor panel 104 is a member having a large area, and the rigidity of the floor panel 104 greatly affects the rigidity of the vehicle body, which is the rigidity of the entire vehicle body 102. Therefore, the floor panel 104 is provided with members such as the side member 106 and the cross member 108 on the lower surface side, and the rigidity is enhanced by these members.

  A pair of side members 106 are provided to extend in the vehicle front-rear direction along both ends of the floor panel 104 in the vehicle width direction (a vehicle left side member 106a and a vehicle right side member 106b). The side members 106 are spot-bonded to the floor panel 104 at various places, and contribute to improving the rigidity of the floor panel 104 by supporting both ends of the floor panel 104 in the vehicle width direction.

  A trailing arm suspension (hereinafter referred to as a suspension 110) that supports a rear tire (not shown) is provided on the rear side of the floor panel 104 in the vehicle. FIG. 2 is an arrow A view of FIG. 1 is a perspective view of the suspension 110 of FIG. 1 as viewed from the lower left side (the front side in the figure) of the left side of the vehicle (the left side in the figure). As shown in FIG. 2, the suspension 110 includes a trailing arm 112, a rear suspension beam 114, and the like. The suspension 110 includes other components such as a coil spring, but these are not shown.

  The trailing arm 112 is a part that supports the rear tire, and absorbs shock and vibration between the vehicle body 102 and the rear tire. In the present embodiment, the trailing arm 112 is connected to a portion of the side member 106 where the rigidity is increased by the cross member 108.

  FIG. 3 is a perspective view showing the cross member 108 positioned above the suspension 110 of FIG. The direction shown in FIG. 3 is the same as that shown in FIG. 2 when viewed from below the left side of the vehicle (left side in the figure) in FIG. The cross member 108 is a member that is inserted into the side members 106a and 106b and supports the floor panel 104 in the vehicle width direction. Cross member 108 is also spot bonded to floor panel 104 at various locations.

  FIG. 4 is a view B in FIG. This arrow B is a view of the end of the cross member 108 in FIG. 3 on the side member 106a side as viewed from the front of the vehicle and the lower side of the vehicle width direction inside the vehicle. As illustrated in FIG. 4, the cross member 108 is provided with an end flange 116, and the end flange 116 is spot-bonded to the bottom surface 118 of the side member 106 a. With this configuration, even if the vehicle width direction is swayed while the vehicle is running, a force is applied to the joining portion of the end flange 116 in a shearing direction that is more rigid. . Therefore, the deformation of the side member 106a is suppressed, and the force applied to the cross member 108 can be suppressed. Moreover, if it is the structure of said joining, it is also possible to suppress the deformation | transformation with respect to the input of the up-down direction to a joining location.

  In particular, the cross member 108 contributes to improving the torsional rigidity of the vehicle body 102 during traveling. Specifically, during traveling, the cross member 108 receives a load in a bending direction or a twisting direction and absorbs it. In this embodiment, in order to further improve the rigidity of the cross member 108 and suppress the deformation thereof, the shape of the cross member 108 is devised. Hereinafter, the configuration of the cross member 108 will be described in detail.

  FIG. 5 is a diagram illustrating the cross member 108 of FIG. 3 independently from each direction. First, FIG. 5A is an arrow C view illustrating the cross member 108 of FIG. 3 as viewed from the front of the vehicle. As shown in FIG. 5A, the cross member 108 has a shape protruding downward from the lower surface of the floor panel 104 (see FIG. 3 and the like).

  FIG.5 (b) is DD sectional drawing of Fig.5 (a). As illustrated in FIG. 5B, the cross member 108 has a hat shape in which a DD cross section viewed from the vehicle width direction protrudes downward. The portion constituting the hat shape includes a front wall portion 120 on the front side of the vehicle, a rear wall portion 122 on the rear side of the vehicle, and a lower end portion 124 connecting the front wall portion 120 and the lower end of the rear wall portion 122. . Then, flange portions 126 a and 126 b are provided on the floor panel 104 from the upper ends of the front wall portion 120 and the rear wall portion 122, respectively. This hat shape is formed over substantially the entire length of the cross member 108.

  As illustrated in FIG. 5A, the cross member 108 has two types of components, a central region E1 in the center in the vehicle width direction and two outer expansion regions E2 and E3 connected to both ends of the central region E1. It is composed of The central region E1 and the outer expansion regions E2 and E3 have different protrusion amounts from the floor panel 104 (see FIG. 3 and the like), the central region E1 has a small protrusion amount, and the outer expansion regions E2 and E3 have a large protrusion amount. It has become. The reason is that the central region E1 needs to be limited to a small projection amount for convenience of layout with other members, and the outer expansion regions E2 and E3 are joined to the bottom surface 118 of the side members 106a and 106b. This is because it is necessary to set a large protrusion amount.

  As described above, the cross member 108 is devised to increase the rigidity. First, the configuration of the shape change lines L1 and L2 will be described. As illustrated in FIG. 5A, the outer expansion regions E <b> 2 and E <b> 3 of the cross member 108 have a portion with a large protruding amount from the floor panel 104. The shape change lines L1 and L2 are locations that are the starting points of changes in the amount of protrusion from the floor panel 104 in the outer extended regions E2 and E3.

  FIG. 5C is a view of the cross member 108 of FIG. As illustrated in FIG. 5C, two shape change lines L <b> 1 and L <b> 2 are provided on the lower end portion 124, both of which are oblique to the vehicle front-rear direction and are formed non-parallel to each other. Yes.

  The two shape change lines L1 and L2 tend to concentrate deformation when bending or twisting force is applied to the cross member 108, and deformation tends to increase. However, in the present embodiment, the two shape change lines L1 and L2 are different from each other in the direction in which they are easily deformed because they are not parallel to each other. Therefore, when a load in a predetermined direction is applied to the cross member 108, even if the load is in a direction that is easily deformed for one of the shape change lines L1 and L2, the load is deformed for the other shape change lines L1 and L2. It will be a difficult direction. High rigidity can be exhibited even with respect to loads in either the vehicle front-rear direction or the vehicle width direction. In the present embodiment, the two shape change lines L1 and L2 are provided so as to be inclined with respect to each other so that the front side of the vehicle is widened. They may be provided in asymmetrical directions.

  Thus, the cross member 108 has an increased bending rigidity due to the shape of the lower end portion 124 thereof, and can exhibit high durability against a load in the bending direction or torsional direction while the vehicle is traveling. Yes. Thus, since the rigidity of the vehicle body 102 (see FIG. 1) is increased by devising the shape of the cross member 108, the weight and cost are not increased as compared with the case of using an additional member.

  There are other ideas for improving the rigidity of the cross member 108. FIG. 6 is a diagram illustrating the cross member 108 of FIG. 5A from another direction. FIG. 6A is a perspective view illustrating the vicinity of the outer expansion region E2 of the cross member 108 in FIG. 5A as viewed from above. As illustrated in FIG. 6A, bracing surfaces 136a and 136b are provided at the end portion 132 connected to the outer expansion region E2 in the central region E1. This bracing surface is also provided at the end of the central region E1 on the outer expansion region E3 side (see FIG. 5A).

  FIG. 6B is a diagram exemplifying the central region E1 of FIG. As illustrated in FIG. 6B, the bracing surfaces 136 a and 136 b obliquely connect the lower end portion 124, the front wall portion 120, and the rear wall portion 122 of the hat-shaped central region E <b> 1. By providing these bracing surfaces 136a and 136b, the rigidity between the lower end portion 124, the front wall portion 120, and the rear wall portion 122 is increased in the central region E1. As a result, the central region E1 is not likely to be distorted such that its hat shape is a parallelogram. Therefore, the rigidity of the entire cross member 108 can be improved, and the rigidity of the vehicle body can be further improved.

  Further, as a configuration for further improving the rigidity of the cross member 108, a cross member center reinforcement 138 is provided in the present embodiment as illustrated in FIG. The cross member center reinforcement 138 is a member that reinforces the cross member 108 by connecting the cross member 108 and the spare tire storage unit 140. Here, the spare tire storage portion 140 is a portion that is formed by the floor panel 104 projecting downward in the vicinity of the rear of the cross member 108 and stores the spare tire. The cross member center reinforcement 138 is spot-bonded to the spare tire storage portion 140, the cross member 108, and the floor panel 104. Thus, by supporting the cross member 108 with the spare tire storage portion 140 via the cross member center reinforcement 138, the rigidity of the cross member 108 in the bending direction and the twisting direction can be further improved.

  In this embodiment, the trailing arm 112 is connected to a portion of the side member 106 reinforced by the above-described cross member 108. Specifically, as illustrated in FIG. 4, a trailing arm bracket 142 is installed in front of the cross member 108 in the side member 106 a, and a coil spring bracket 144 for the coil spring of the suspension 110 is behind the cross member 108. Is provided. The trailing arm 112 in FIG. 2 is connected so as to extend over the trailing arm bracket 142 and the coil spring bracket 144. With this configuration, the trailing arm 112 is connected to a portion of the side member 106 where the rigidity is enhanced by the cross member 108, so that it is possible to more efficiently absorb loads, vibrations, and the like transmitted from the tire. .

  As described above, according to the vehicle body cross member structure 100 of the present embodiment, the rigidity of the cross member 108 can be increased by a simple configuration, and the vehicle body rigidity can be improved. Further, since the rigidity is mainly improved due to the shape of the cross member 108, the weight and cost are not increased as compared with the case of using an additional member, and the layout space on the vehicle body is reduced. It is suitable because it has little influence.

  As mentioned above, although preferred embodiment of this invention was described referring an accompanying drawing, it cannot be overemphasized that this invention is not limited to the example which concerns. It will be apparent to those skilled in the art that various changes and modifications can be made within the scope of the claims, and these are naturally within the technical scope of the present invention. Understood.

  The present invention is used in a vehicle body cross member structure including a floor panel, a pair of side members extending in the vehicle front-rear direction along both ends of the floor panel in the vehicle width direction, and a cross member inserted between the pair of side members. be able to.

E1 ... center region, E2 ... vehicle outer left extension region, E3 ... vehicle right outer extension region, L1, L2 ... shape change line, 100 ... vehicle body cross member structure, 102 ... vehicle body, 104 ... floor panel, 106 ... side Member 106a ... side member on the left side of the vehicle, 106b ... side member on the right side of the vehicle, 108 ... cross member, 110 ... suspension, 112 ... trailing arm, 114 ... rear suspension beam, 116 ... end flange, 118 ... side member Bottom surface, 120 ... front wall portion of cross member, 122 ... rear wall portion of cross member, 124 ... lower end portion, 126a ... flange portion continuing from front wall portion, 126b ... flange portion continuing from rear wall portion, 132 ... of cross member End of vehicle left side, 136a, 136b ... bracing Surface, 138 ... cross member center reinforcement, 140 ... spare tire storage space, 142 ... trailing arm bracket, 144 ... coil spring bracket

Claims (4)

A floor panel constituting the floor of the vehicle body;
A pair of side members provided on the lower surface side of the floor panel and extending in the vehicle front-rear direction along both ends in the vehicle width direction of the floor panel;
A cross member that is inserted between the pair of side members and supports the floor panel in the vehicle width direction;
With
A cross-section of the cross member viewed from the vehicle width direction has a hat shape protruding downward from the floor panel, and the cross member further includes a central region located at the center in the vehicle width direction and both ends of the central region. Two outer expansion regions each extending outward in the vehicle width direction and having a portion having a larger amount of protrusion of the hat shape than the central region,
When the cross member is viewed from below, the two shape change lines that are the starting points of the change in the amount of protrusion of the hat shape are both oblique to the vehicle longitudinal direction and formed non-parallel to each other. Body cross member structure characterized by The vehicle body cross member structure further includes a trailing arm suspension that supports the tire with a trailing arm.
2. The vehicle body cross member structure according to claim 1, wherein the trailing arm is connected to the side member over a portion of the side member before and after the cross member. The central region and the outer extension region of the cross member are independent parts,
The center region has braces that obliquely connect the lower end portion of the hat, the front wall portion, and the rear wall portion at an end portion connected to the outer extension region. Body cross member structure as described. The vehicle body cross member structure further includes
A spare tire storage part in which the floor panel protrudes downward in the vicinity of the rear of the cross member and stores a spare tire;
A cross member center reinforcement for reinforcing the cross member by connecting the cross member and the spare tire storage unit;
The vehicle body cross member structure according to any one of claims 1 to 3, further comprising:

Images