JP6848661B2 - Vehicle undercarriage - Google Patents

Description

The present invention relates to a vehicle lower structure.

A vehicle lower structure in which a suspension called a "torsion beam type suspension" is attached to the rear of the lower part of the vehicle is already known (see, for example, Patent Document 1). In this torsion beam type suspension, a pair of trailing arms extending in the front-rear direction of the vehicle are arranged on both sides of the vehicle, and these pair of trailing arms are connected by a torsion beam extending in the vehicle width direction. The front ends of the pair of trailing arms are attached to side sills and side members arranged on both sides of the vehicle via trailing arm support portions such as brackets.

Japanese Unexamined Patent Publication No. 2013-18383

In the vehicle lower structure described above, since a large load is input to the trailing arm support portion and its vicinity, in order to suppress deformation of the portion with a small number of parts, the strength and rigidity of the portion are balanced. It needed to be strengthened, and in this respect the conventional vehicle undercarriage had room for improvement.

The present invention has been made from such a viewpoint, and it is an object of the present invention to provide a vehicle lower structure capable of increasing the strength and rigidity of a side member to which a load from a suspension is input and suppressing deformation with a small number of parts. To do.

In the vehicle lower structure of the present invention, a pair of side members extending in the vehicle front-rear direction are arranged on both sides of the vehicle, and a cross member extending in the vehicle width direction is arranged between the pair of side members. The side members and both ends of the cross member are connected by cross member extensions, respectively, and the lower surface of the cross member is located above the lower surfaces of the pair of side members, and the pair of cross members. In a vehicle lower structure in which the extension is bent downward at an adjacent end on the side member side and has a vertical wall portion overlapped on the inner side surface in the vehicle width direction of the side member, the pair of cross member extensions is used. The inclined surface portion has an inclined surface portion connecting the lower surface of the cross member and the lower surface of the side member, and a second inclined surface portion connecting the lower surface of the cross member to the inner side surface of the side member in the vehicle width direction. Is characterized in that it is inclined more than the second inclined surface portion.
In the vehicle lower structure of the present invention, a pair of side members extending in the vehicle front-rear direction are arranged on both sides of the vehicle, and a cross member extending in the vehicle width direction is arranged between the pair of side members. In a vehicle lower structure in which the side members of the cross member and both ends of the cross member are connected by cross member extensions, and the lower surface of the cross member is located above the lower surfaces of the pair of side members. A pair of cross member extensions are bent downward at an adjacent end on the side member side and overlapped with the inner side surface in the vehicle width direction of the side member, and the lower surface of the cross member and the side member. of and the inclined surface portion that connects the lower surface has a pair of trailing arm support portions are respectively fixed to the pair of side members, the pair of trailing arm support portion, of the cross member at both ends Arranged on an extension line, a reinforcing member is coupled to the inside of each trailing arm support portion in the vehicle width direction, the reinforcing member is fixed to the side member, and the reinforcing member is the inner surface of the side member and the said. It is characterized by having a flange portion overlapped with the vertical wall portion of the cross member extension.

According to the vehicle lower structure of the present invention, it is possible to increase the strength and rigidity of the side member to which the load from the suspension is input and suppress the deformation of the side member with a small number of parts.

It is a bottom view of the vehicle to which the vehicle lower structure according to the embodiment of the present invention is applied. It is an enlarged view of the part D of FIG. 1 (the rear suspension is omitted). It is sectional drawing along the line AA in FIG. It is sectional drawing along the line BB in FIG. It is a perspective view of the part D of FIG. 1 (the rear suspension is omitted). It is a bottom view of the part of FIG. 5 (rear suspension is omitted).

In the present invention, a pair of side members extending in the front-rear direction of the vehicle are arranged on both sides of the vehicle, and a cross member extending in the vehicle width direction is arranged between the pair of side members, and the pair of side members and the cross member are arranged. In a vehicle lower structure in which both ends are connected by cross member extensions and the lower surface of the cross member is located above the lower surfaces of the pair of side members, the pair of cross member extensions are adjacent to each other. It has a vertical wall portion that is bent downward at the end portion on the member side and overlapped with the inner side surface in the vehicle width direction of the side member, and an inclined surface portion that smoothly connects the lower surface of the cross member and the lower surface of the side member. It is a vehicle substructure characterized by the fact that it is used.

According to the above configuration, the strength of the side member is increased by overlapping the vertical wall portion on the inner surface of the side member in the vehicle width direction, and the cross-sectional deformation of the side member due to the load input from the suspension in the vehicle vertical direction is suppressed. be able to. In addition, the inclined surface portion smoothly connects the lower surface of the cross member and the lower surface of the side member to increase the rigidity of the side member and suppress the cross-sectional deformation of the side member due to the load input from the suspension in the left-right direction of the vehicle. be able to. As described above, the vehicle lower structure of the present invention can strengthen the strength and rigidity of the side member to which the load from the suspension is input in a well-balanced manner, so that the deformation of the side member can be suppressed with a small number of parts. ..

Hereinafter, examples of the present invention will be described with reference to the drawings. The vehicle lower structure 1 of the present embodiment shown in FIGS. 1 to 6 is applied to an automobile. Further, the arrow FRONT in the figure represents the front in the vehicle front-rear direction, the arrow IN represents the inside in the vehicle width direction, and the arrow UP represents the upper direction in the vehicle vertical direction.

FIG. 1 is a bottom view of a vehicle 10 to which the vehicle lower structure 1 according to the embodiment of the present invention is applied. In FIG. 1, reference numeral 2 is a side member. Further, reference numeral 2L is a side member arranged on the left side of the vehicle 10, and reference numeral 2R is a side member arranged on the right side of the vehicle 10. In the present specification, the "left side of the vehicle 10" means the left side of the vehicle 10 as seen from the driver. Similarly, the "right side of the vehicle 10" means the right side of the vehicle 10 as seen by the driver. Reference numeral 3 is a cross member. Reference numeral 4 is a cross member extension. Further, reference numeral 4L is a cross member extension arranged on the left side of the vehicle 10, and reference numeral 4R is a cross member extension arranged on the right side of the vehicle 10.

In FIG. 1, reference numeral 7 is a rear suspension. Reference numeral 71 is a torsion beam constituting the rear suspension 7. Reference numeral 72 is a trailing arm constituting the rear suspension 7. Reference numeral 73 is a spring mounting portion for mounting the spring of the rear suspension 7. Reference numeral 74 is a bracket for attaching the shock absorber of the rear suspension 7.

In FIG. 1, reference numeral 5 is a trailing arm support portion that supports the front end portion 72a of the trailing arm 72. Further, reference numeral 5L is a trailing arm support portion arranged on the left side of the vehicle 10, and reference numeral 5R is a trailing arm support portion arranged on the right side of the vehicle 10. Reference numeral 6 is a reinforcing member of the trailing arm support portion 5. Further, reference numeral 6L is a reinforcing member arranged on the left side of the vehicle 10, and reference numeral 6R is a reinforcing member arranged on the right side of the vehicle 10.

In FIG. 1, reference numeral 9 is a side sill. Further, reference numeral 9L is a side sill arranged on the left side of the vehicle 10, and reference numeral 9R is a side sill arranged on the right side of the vehicle 10. Reference numeral 11 denotes a rear floor panel.

As shown in FIG. 1, a pair of side sills 9L and 9R extending in the vehicle front-rear direction are arranged on both sides of the vehicle 10, and extend in the vehicle front-rear direction inside the pair of side sills 9L and 9R. A pair of side members 2L and 2R are arranged. A cross member 3 extending in the vehicle width direction is arranged between the pair of side members 2L and 2R and below the rear floor panel 11. The pair of side members 2L and 2R and both ends of the cross member 3 are connected by cross member extensions 4L and 4R, respectively. The pair of trailing arm support portions 5L and 5R are arranged on the extension lines of both ends of the cross member 3 and are arranged in the space provided between the rear end of the side sill 9 and the side member 2. Then, the reinforcing members 6L and 6R are arranged inside the trailing arm support portions 5L and 5R in the vehicle width direction. Further, the torsion beam 71 is arranged behind the cross member 3. Further, as shown in FIGS. 3 and 4, the lower surface 31 of the cross member 3 is located above the lower surface 21 of the pair of side members 2L and 2R.

The pair of side members 2L and 2R are formed by pressing a metal plate. As shown in FIGS. 3 and 4, the pair of side members 2L and 2R are the lower surface 21, the inner side surface 22 bent upward at the inner end portion of the lower surface 21 in the vehicle width direction, and the outer surface of the lower surface 21 in the vehicle width direction. It has an outer surface 23 bent upward at the end, and is formed in a U-shaped cross section. The upper end portion of the inner side surface 22 and the upper end portion of the outer surface 23 are welded to the floor side panel 13 connected to the side of the rear floor panel 11.

The cross member 3 is formed by pressing a metal plate. Cross member 3, as shown in FIG. 2 and 5, a rear floor panel 11 and the opposing lower surface 31, a side surface 32 before the bent upwards at a front end portion of the lower surface 31 at the rear end portion of the lower surface 31 the side surface 33 after being bent upward, and a joint portion 34, 35 welded to the rear floor panel 11.

Since the pair of cross member extensions 4L and 4R have symmetrical shapes, the configuration of the cross member extensions 4R will be described as a representative. The cross member extension 4R is formed by pressing a metal plate. As shown in FIGS. 4 and 5, the cross member extension 4R includes a cross member joint portion 41, a side member joint portion 45, an inclined surface portion 42, a second inclined surface portion 43, a vertical wall portion 44, and a front side surface 46. It has a rear side surface 47 and floor panel joints 48 and 49.

The cross member joint portion 41 is a portion that is overlapped and welded to the outer end portion of the lower surface 31 of the cross member 3 in the vehicle width direction. The side member joint portion 45 is a portion that is overlapped and welded on the lower surface 21 of the adjacent side member 2R.

The inclined surface portion 42 is an inclined surface that smoothly connects the cross member joint portion 41 and the side member joint portion 45. The end portion of the inclined surface portion 42 on the side member 2R side is located at the inner end portion in the vehicle width direction on the lower surface 21 of the side member 2R. That is, the inclined surface portion 42 smoothly connects the lower surface 31 of the cross member 3 and the lower surface 21 of the side member 2R.

The second inclined surface portion 43 is an inclined surface that is connected to the cross member joint portion 41 and extends to the inner side surface 22 of the side member 2R. The end portion of the second inclined surface portion 43 on the side member 2R side is located above the lower surface 21 of the side member 2R. The second inclined surface portion 43 is adjacent to the inclined surface portion 42 in the front-rear direction of the vehicle, and is located behind the inclined surface portion 42. The inclined surface portion 42 and the second inclined surface portion 43 are inclined downward as they approach the side member 2R side from the cross member joint portion 41. These inclination angles are different, and the inclination angle of the inclined surface portion 42 is larger than the inclination angle of the second inclined surface portion 43.

The vertical wall portion 44 is bent downward at the end portion of the second inclined surface portion 43 on the side member 2R side, and extends to the lower surface 21 of the side member 2R. The vertical wall portion 44 is overlapped and welded on the inner side surface 22 of the side member 2R. The vertical wall portion 44 is adjacent to the inclined surface portion 42 in the front-rear direction of the vehicle, and is located behind the inclined surface portion 42. Further, the vertical wall portion 44 connects the second inclined surface portion 43 and the side member joint portion 45.

The side member joint portion 45 is bent outward in the vehicle width direction at the end portions of the inclined surface portion 42 and the vertical wall portion 44. The side member joint portion 45 extends from the inner end portion in the vehicle width direction on the lower surface 21 of the side member 2R to the central portion in the vehicle width direction on the lower surface 21.

The front side surface 46 is a portion bent upward at the front end portion of the cross member joint portion 41 and the inclined surface portion 42. The rear side surface 47 is a portion bent upward at the rear end portion of the cross member joint portion 41 and the second inclined surface portion 43.

Floor panel joint 48 is bent forward at the upper end portion of the front side surface 46, are welded are overlapped on the rear floor panel 11. Floor panel joint 49 is bent backward at the upper end of the rear side 47, are welded are overlapped on the rear floor panel 11.

As shown in FIG. 6, the ridge line formed at the front end of the lower surface of the cross member extension 4R is along the inclined surface portion 42 described above, and this ridge line is continuous with the ridge line formed at the front end of the lower surface 31 of the cross member 3. ing. Reference numeral L1 is attached to the ridgeline at the front end of the lower surface 31 of the continuous cross member 3 and the ridgeline at the front end of the lower surface of the cross member extension 4R. The ridge line L1 intersects the ridge line L2 formed at the inner end portion in the vehicle width direction on the lower surface 21 of the side member 2R. That is, the lower surface front portion of the cross member extension 4R having the inclined surface portion 42 connects the lower surface 31 of the cross member 3 and the lower surface 21 of the side member 2R. Further, the ridge line formed at the rear end of the lower surface of the cross member extension 4R is continuous with the ridge line formed at the rear end of the lower surface 31 of the cross member 3. Reference numeral L3 is attached to the ridgeline at the rear end of the lower surface 31 of the continuous cross member 3 and the ridgeline at the rear end of the lower surface of the cross member extension 4R.

Since the pair of trailing arm support portions 5L and 5R have a symmetrical shape, the configuration of the trailing arm support portion 5R will be described as a representative. As shown in FIG. 4, the trailing arm support portion 5R has an inner bracket 51 welded to the outer surface 23 of the side member 2R and an outer bracket 54 welded to the side sill 9R. The outer bracket 54 is composed of a facing portion 52 facing the inner bracket 51 at a distance, and a connecting portion 53 connecting the facing portion 52 and the inner bracket 51. The trailing arm 72 has a front end portion 72a arranged between the inner bracket 51 and the facing portion 52, and is rotatably supported by the trailing arm support portion 5.

Since the pair of reinforcing members 6L and 6R have symmetrical shapes, the configuration of the reinforcing members 6R will be described as a representative. The reinforcing member 6R is formed by pressing a metal plate. As shown in FIG. 5, the reinforcing member 6R includes an inner bracket joint surface 61 welded to the inner portion of the inner bracket 51 of the trailing arm support portion 5R in the vehicle width direction, a flange portion 63, and an inner reinforcing portion 62. It has a front reinforcing portion 64 and a side member joint portion 65.

The inner bracket joint surface 61 is preferably arranged so that at least a part of the vertical wall portion 44 of the cross member extension 4R in the vehicle front-rear direction overlaps with the vehicle side view. It is arranged so that almost the entire area overlaps.

The flange portion 63 is a portion that is overlapped and welded to the vertical wall portion 44 of the cross member extension 4R. That is, in the E portion in FIG. 4, the inner side surface 22 of the side member 2R, the vertical wall portion 44 of the cross member extension 4R, and the flange portion 63 of the reinforcing member 6R are stacked and welded in this order.

The inner reinforcing portion 62 is a portion extending from the rear end of the inner bracket joint surface 61 to the flange portion 63. The inner reinforcing portion 62 is arranged near the rear end on the lower surface of the cross member extension 4R. As shown in FIG. 6, the inner reinforcing portion 62 is formed with a ridge line L4 that intersects with the ridge line L2 inside the lower surface 21 of the side member 2R. The ridge line L4 of the inner reinforcing portion 62 is located on an extension line of the ridge line L3 at the rear end of the lower surface of the cross member 3 and the cross member extension 4R when viewed from the bottom surface side of the vehicle 10.

The front reinforcing portion 64 extends forward from the front end of the inner bracket joint surface 61 to the lower surface 21 of the side member 2R. The front end of the front reinforcing portion 64 is located on an extension of the ridge line L1 of the front end of the lower surface of the cross member 3 and the cross member extension 4R. That is, as shown in FIG. 6, a ridge line L5 intersecting the lower surface 21 of the side member 2R is formed in the front reinforcing portion 64, and the front end of the ridge line L5 is the lower surface front end of the cross member 3 and the cross member extension 4R. It is located on the extension of the ridgeline L1 of. The front reinforcing portion 64 is preferably arranged so that at least a part of the inclined surface portion 42 of the cross member extension 4R in the vehicle front-rear direction overlaps with the vehicle side view. Are arranged so that they overlap.

The side member joint portion 65 is connected to the upper end of the inner bracket joint surface 61, the upper end of the inner reinforcing portion 62, and the upper end of the front side reinforcing portion 64. The side member joint portion 65 is overlapped with and welded to the lower surface 21 of the side member 2R and the side member joint portion 45 of the cross member extension 4R.

Further, as shown in FIG. 5, a reinforcing member 8 is provided inside the side member 2R so as to connect the ridge line L1 of the cross member extension 4R and the front reinforcing portion 64 of the reinforcing member 6R. Similarly, inside the side member 2L, a reinforcing member 8 is provided so as to connect the ridge line L1 of the cross member extension 4L and the front reinforcing portion 64 of the reinforcing member 6L.

According to the vehicle lower structure 1 having the above configuration, the load in the vehicle vertical direction input to the trailing arm support portions 5L and 5R is received by the inner side surfaces 22 of the side members 2L and 2R via the reinforcing members 6L and 6R. Can be done. The strength of the inner side surface 22 is increased by overlapping the vertical wall portions 44 of the cross member extensions 4L and 4R and the flange portions 63 of the reinforcing members 6L and 6R in the vicinity of the trailing arm support portions 5L and 5R. .. Therefore, it is possible to suppress the cross-sectional deformation of the side members 2L and 2R due to the load input to the trailing arm support portions 5L and 5R in the vertical direction of the vehicle. Further, the inclined surface portion 42 of the cross member extensions 4L and 4R smoothly connects the lower surface 31 of the cross member 3 and the lower surface 21 of the side members 2L and 2R. As a result, the rigidity of the side members 2L and 2R can be increased, and the cross-sectional deformation of the side members 2L and 2R due to the load input to the trailing arm support portions 5L and 5R in the left-right direction of the vehicle can be suppressed.

As described above, according to the vehicle lower structure 1, the strength of the side members 2L and 2R can be increased while increasing the rigidity of the side members 2L and 2R, that is, the vehicle body rigidity, with a small number of parts. Therefore, it is possible to effectively suppress the deformation of the side members 2L and 2R due to the load in the vehicle vertical direction or the vehicle left and right direction input to the trailing arm support portions 5L and 5R during traveling.

Further, in the vehicle lower structure 1, as described above, the reinforcing members 6L and 6R are coupled to the inside of the trailing arm support portions 5L and 5R in the vehicle width direction, and the reinforcing members 6L and 6R are included in the side members 2L and 2R. It has a flange portion 63 overlapped with the vertical wall portions 44 of the side surface 22 and the cross member extensions 4L and 4R. As a result, the load input to the trailing arm support portions 5L and 5R can be reliably guided to the vertical wall portion 44. That is, the load input to the trailing arm support portions 5L and 5R can be reliably guided to the portion where the strength is increased by the vertical wall portion 44 of the inner side surface 22, and the side members 2L and 2R are deformed. It can be effectively suppressed.

Further, in the vehicle lower structure 1, as described above, the reinforcing members 6L and 6R have an inner reinforcing portion 62 extending from the inner bracket joint surface 61 to the flange portion 63, and the inner reinforcing portion 62 is a cross member extension 4L. , 4R is located near the rear end on the lower surface. The vertical wall portion 44 described above is provided at the rear end of the lower surface of the cross member extensions 4L and 4R. As a result, the load input to the trailing arm support portions 5L and 5R can be reliably guided to the portion where the strength is increased by the vertical wall portion 44 of the inner side surface 22, and the side members 2L and 2R are deformed. Can be effectively suppressed.

Further, as described above, the vehicle lower structure 1 has a front reinforcing portion 64 in which the reinforcing members 6L and 6R extend forward from the inner bracket joint surface 61 to the lower surface 21 of the side members 2L and 2R. The front end of the front reinforcing portion 64 is located on an extension of the ridge line L1 formed at the front end on the lower surfaces of the cross member extensions 4L and 4R. As a result, the rigidity of the side members 2L and 2R can be increased, and the cross-sectional deformation of the side members 2L and 2R due to the load input to the trailing arm support portions 5L and 5R in the left-right direction of the vehicle can be suppressed. Further, the rigidity of the side members 2L and 2R, that is, the rigidity of the vehicle body can be increased, and the rigidity of the trailing arm support portions 5L and 5R can be increased, so that the maneuverability can be improved.

In the above-described embodiment, the vertical wall portions 44 of the cross member extensions 4L and 4R and the flange portions 63 of the reinforcing members 6L and 6R are formed in the vicinity of the trailing arm support portions 5L and 5R on the inner side surfaces 22 of the side members 2L and 2R. It was piled up. In the present invention, it is more preferable that the three sheet metals of the inner side surface 22, the vertical wall portion 44, and the flange portion 63 are overlapped in this way, but the flange portion 63 is overlapped with the vertical wall portion 44. Is not an essential configuration, and at least the vertical wall portion 44 may be overlapped with the inner side surface 22. Even in this case, the strength of the inner side surface 22 can be increased, and the cross-sectional deformation of the side members 2L and 2R can be suppressed.

Further, in the above-described embodiment, the inclined surface portion 42 and the vertical wall portion 44 are adjacent to each other in the front-rear direction of the vehicle, and the vertical wall portion 44 is located behind the inclined surface portion 42. The wall portion 44 may be located in front of the inclined surface portion 42. In that case, the positional relationship between the inner reinforcing portion 62 and the front reinforcing portion 64 may be reversed, and the inner reinforcing portion 62 may be arranged near the front end on the lower surface of the cross member extension 4R.

The best configuration, method, and the like for carrying out the present invention are disclosed in the above description, but the present invention is not limited thereto. That is, the present invention is mainly illustrated and described with respect to specific embodiments, but without departing from the scope of the technical idea and purpose of the present invention, the shape with respect to the above-described embodiments. , Materials, quantities, and other detailed configurations can be modified by those skilled in the art. Therefore, the description that limits the shape, material, etc. disclosed above is merely an example for facilitating the understanding of the present invention, and does not limit the present invention. Therefore, those shapes, materials, etc. The description by the name of the member which removes a part or all of the limitation such as is included in the present invention.

1 Vehicle lower structure 2 Side member 3 Cross member 4 Cross member extension 5 Trailing arm support 21 Lower surface of side member 22 Inner surface of sad member 31 Lower surface of cross member 42 Inclined surface 44 Vertical wall

Claims (4)

A pair of side members extending in the front-rear direction of the vehicle are arranged on both sides of the vehicle.
A cross member extending in the vehicle width direction is arranged between the pair of side members.
The pair of side members and both ends of the cross member are connected by cross member extensions, respectively.
The lower surface of the cross member is located above the lower surface of the pair of side members .
In a vehicle lower structure having a vertical wall portion in which the pair of cross member extensions are bent downward at an adjacent end on the side member side and overlapped with the inner side surface in the vehicle width direction of the side member.
Said pair of cross members extensions, the inclined surface that connects the lower surface of the side members and the lower surface of the cross member, and a second inclined surface that connects the vehicle width direction inner side of the side members from the underside of the cross member , has a,
The vehicle lower structure is characterized in that the inclined surface portion is inclined more than the second inclined surface portion. A pair of side members extending in the front-rear direction of the vehicle are arranged on both sides of the vehicle.
A cross member extending in the vehicle width direction is arranged between the pair of side members.
The pair of side members and both ends of the cross member are connected by cross member extensions, respectively.
In the vehicle lower structure in which the lower surface of the cross member is located above the lower surface of the pair of side members.
The pair of cross member extensions are bent downward at an adjacent end on the side member side and overlapped with the inner side surface in the vehicle width direction of the side member, and the lower surface and the side surface of the cross member. It has an inclined surface portion that connects the lower surface of the member , and has.
A pair of trailing arm supports are fixed to the pair of side members, respectively.
The pair of trailing arm support portions are arranged on the extension lines of both ends of the cross member.
A reinforcing member is coupled to the inside of each trailing arm support portion in the vehicle width direction, and the reinforcing member is fixed to the side member.
A vehicle lower structure , wherein the reinforcing member has a flange portion overlapped with an inner side surface of the side member and the vertical wall portion of the cross member extension. The reinforcing member has an inner reinforcing portion extending from a joint surface with the trailing arm support portion to the flange portion.
The vehicle lower structure according to claim 2, wherein the inner reinforcing portion is arranged in the vicinity of the front end or the rear end on the lower surface of the cross member extension. The reinforcing member has a front reinforcing portion extending in front of the vehicle from a joint surface with the trailing arm support portion to the lower surface of the side member.
The vehicle lower structure according to claim 3, wherein the front end of the front reinforcing portion is located on an extension line of a ridge line formed at the front end on the lower surface of the cross member extension.

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