JP5505287B2 - Rear body structure - Google Patents

Description

  The present invention relates to a rear body structure for improving the rigidity of an automobile body.

As is well known, in order to absorb the increase in weight due to improvements in fuel efficiency and athletic performance of automobiles, safety measures and equipment enhancement, it is required to reduce the weight of automobiles. The weight of the vehicle body is being reduced by reducing the thickness of the vehicle body structure.
For example, when a 590 MPa class high-strength steel plate is used to reduce the weight of the vehicle body, it is possible to achieve a weight reduction of about 40% compared to the conventional steel plate while ensuring the strength of the vehicle body. Can do.

On the other hand, since automobiles receive various forces such as the force received from road surface irregularities during travel and the impact when riding on road shoulders, etc., torsional rigidity is required in addition to vehicle body strength. When the vehicle body structure is made thinner, the torsional rigidity generally decreases even if the vehicle body strength is ensured.
This is because the Young's modulus of iron is constant even if the tensile strength of the steel sheet is improved due to temperature history, components, etc., and when the vehicle body structure is thinned, the cross-sectional secondary pole moment becomes smaller. This is because the torsional rigidity decreases.
Therefore, when the vehicle body is thinned and lightened, it is necessary to improve torsional rigidity.

For example, the torsional rigidity of the vehicle body is evaluated by measuring a torsion angle or a load corresponding to the torsion angle as shown in FIG. 9 using a torsional rigidity measuring method as shown in FIG.
FIG. 8 is a conceptual diagram showing a method for measuring torsional rigidity of the white body (vehicle body) 100, and FIG. 9 is a view for explaining torsional rigidity based on the torsion of the front axle center 100F with reference to the rear axle center 100R.

  For example, as shown in FIG. 8A, the torsional rigidity is measured by fixing the white body 100 with the rear axle center (rear axle position) 100R by the rear strut R, and the front axle center ( Evaluation is based on an average torsional rigidity value GJ obtained by applying a torsional torque to the front axle position 100F. (G: transverse elastic modulus, J: cross-sectional polar second moment)

  The torsion torque T with respect to the front axle center 100F is, for example, as shown in FIG. 8B as a view taken along arrow YY in FIG. 8A, with the upper ends of the dummy bars 101 on the left and right front struts FL and FR, respectively. Mounting is performed by rotating the seesaw base 102 to which the lower end of the dummy bar 101 is attached around the axis O.

The torsional rigidity value GJ is shown in FIG. 9 as a view taken along the line XX in FIG. 8 (A). It is calculated based on the displacements δL and δR. In FIG. 9, 100D indicated by a two-dot chain line and a solid line indicates the vehicle body (outer shape) of the front axle center 100F before and after the torsion torque T is applied.
Here, the torsion angle θ (rad) due to the torsion torque T is small.
θ≈tan θ = ((δL + δR) / B); (B is a vehicle body width dimension related to the torsion torque T load at the front axle center 100F).
Torsional rigidity value GJ = (T / (θ / wheelbase length L))
= (T · B · Wheelbase length L) / (δL + δR)
It becomes. (See, for example, “Strength of Automobiles” (Sankaido Co., Ltd., October 30, 1990, second print))

  For improving the torsional rigidity of the vehicle body, for example, techniques disclosed in Patent Documents 1 to 4 are disclosed as techniques focusing on the rear vehicle body structure.

JP-A-8-276865 Japanese Patent Laid-Open No. 2006-256351 JP 2006-193047 A

  However, in order to promote weight reduction by reducing the thickness of the vehicle body structure, the above prior art alone is not sufficient, and there is a strong demand for a more effective technique that is intended to improve the future strength of high-tensile steel sheets.

  The present invention has been made in view of such circumstances, and the rear body structure that can efficiently improve the torsional rigidity of the body of an automobile, and further, by thinning using a high-tensile steel plate, An object of the present invention is to provide a rear vehicle body structure that can improve the efficiency efficiently.

In order to solve the above problems, the present invention proposes the following means.
The invention according to claim 1 is provided in each of the floor panel, the rear wheel house formed on the left and right portions of the floor panel, the strut tower provided corresponding to the rear wheel house, and the rear wheel house. A rear vehicle body structure including left and right rear pillars connected to each other, a seat back side panel formed between a living room and a trunk room, and a rear cross member connecting the left and right rear pillars behind the seat back side panel. A first reinforcing member disposed on the side of the seat back side panel, a connecting member connecting the seat back side panel and the first reinforcing member, and the seat back side panel A second reinforcing member disposed on the trunk room side, wherein the second reinforcing member is There wherein is supported on the rear cross member, characterized in that the is configured to support each other across the seat back side panels and the rear cross member.

According to the rear vehicle body structure relating to the present invention, the first reinforcing member disposed on the side of the seat back side panel and the second reinforcing member disposed on the trunk room side of the seat back side panel across the seat back side panel. Since the second reinforcing member is supported by the rear cross member, the out-of-plane deformation of the seat back side panel is suppressed, and the torsional rigidity can be improved. Further, since the seat back side panel is supported by the second reinforcing member with the rear cross member interposed therebetween, it is possible to suppress the load in the vehicle body front-rear direction from being applied to the seat back side panel. As a result, the torsional rigidity can be improved efficiently.

The invention according to claim 2 includes a floor panel, a rear wheel house formed on left and right portions of the floor panel, a rear strut tower provided corresponding to the rear wheel house, and each of the rear wheel house. Rear vehicle body structure including left and right rear pillars connected to each other, a seat back side panel formed between a living room and a trunk room, and a rear cross member for connecting the left and right rear pillars behind the seat back side panel A first reinforcing member disposed on the side of the seat back side panel, a connecting member connecting the seat back side panel and the first reinforcing member, and the seat back side panel and a second reinforcing member disposed on the trunk room side, the second reinforcing member, Part is supported on the rear cross member, the contact with the upper portion of the rear cross member, characterized in that it is configured to support the seat back side panels.

According to the rear vehicle body structure relating to the present invention, the first reinforcing member disposed on the side of the seat back side panel and the second reinforcing member disposed on the trunk room side of the seat back side panel across the seat back side panel. Since the second reinforcing member is supported by the rear cross member, the out-of-plane deformation of the seat back side panel is suppressed, and the torsional rigidity can be improved. Further, since the seat back side panel is supported by the second reinforcing member supported on the upper portion of the rear cross member, it is possible to suppress the load in the vehicle longitudinal direction from being applied to the seat back side panel. As a result, the torsional rigidity can be improved efficiently.

The invention according to claim 3 is the rear vehicle body structure according to claim 1 or 2 , wherein the second reinforcing member extends to an upper end portion of the seat back side panel. Features.

  According to the rear vehicle body structure relating to the present invention, since the second reinforcing member extends to the upper end portion of the seat back side panel, the rigidity can be improved over the entire length of the seat back side panel.

  According to the rear vehicle body structure relating to the present invention, the torsional rigidity of the vehicle body of an automobile can be efficiently improved.

It is a figure showing the outline of the whole structure of the body concerning a 1st embodiment of the present invention. It is a perspective view showing the outline of the rear body structure concerning a 1st embodiment. It is a figure which shows the reinforcement structure which concerns on 1st Embodiment, (A) is the figure seen from the side, (B) is a figure which shows a cross section. It is a figure which shows the reinforcement structure which concerns on 2nd Embodiment, (A) is the figure seen from the side, (B) is a figure which shows a cross section. It is a figure which shows the reinforcement structure which concerns on 3rd Embodiment, (A) is the figure seen from the side, (B) is a figure which shows a cross section. It is a figure which shows the reinforcement structure which concerns on 4th Embodiment, (A) is the figure seen from the side, (B) is a figure which shows a cross section. It is a figure explaining the modification of the rear part vehicle body structure concerning this invention. It is the schematic which shows an example of the torsional rigidity measurement method of a vehicle body, (A) is a position which applies the load in the longitudinal direction of a vehicle body structure, (B) is a YY arrow line view in (A), It is a figure explaining the outline of the torque generation in the width direction of a vehicle body. It is a figure explaining the torsional rigidity of a vehicle body, and is a XX arrow line view in FIG. 8 (A), and is a figure explaining the displacement and torsion angle of a vehicle body before and after applying torsion torque.

Hereinafter, a first embodiment of the present invention will be described with reference to FIGS. 1 to 3.
FIG. 1 is a diagram showing an outline of a vehicle body structure according to the first embodiment of the present invention. Reference numeral 1 denotes, for example, a vehicle body structure related to a monocoque body, and reference numeral 10 denotes a rear vehicle body structure.
In the vehicle body structure 1, constituent members are made of, for example, 590 MPa class high-tensile steel, and unless otherwise specified, each member is connected by spot welding (note that spot welding is appropriately described. ).

  As shown in FIG. 2, the rear vehicle body structure 10 includes, for example, a floor panel 15, a rear wheel house 20, a rear cross member 16, a rear strut tower 25, a seat back panel 40, a rear pillar 50, and a parcel panel. 60 and a reinforcing structure 70, and has a trunk-through opening 41.

In this embodiment, the rear cross member 16 is formed so as to connect the left and right rear pillars 50 on the floor panel 50. For example, the rear cross member 16 has a substantially trapezoidal shape with a narrow upper part. The rear cross member 16 may be configured to be connected to the floor panel 50, or may be configured to be integrally formed with the floor panel 50.
Further, instead of connecting the left and right rear pillars 50 by the rear cross member 16, the left and right rear wheel houses 20 may be connected to each other.

The rear wheel house 20 includes left and right rear wheel houses 20L and 20R. The rear wheel house 20 bulges inward in the width direction of the rear vehicle body structure 10 and is formed to open outward and downward in the width direction.
Further, the rear wheel houses 20L and 20R are connected to concave peripheral portions corresponding to the rear wheel houses 20L and 20R formed on the left and right portions of the floor panel 15 by spot welding, for example.

  The rear strut tower 25 is provided corresponding to the left and right rear wheel houses 20, and in this embodiment, for example, at the center position (rear axle center 10R) of the rear wheel house 20 in the front-rear direction of the rear vehicle body structure 10. It is formed adjacent to the inner position of the rear wheel house 20L, 20R in the width direction.

In this embodiment, the seat back panel 40 includes left and right seat back side panels 40L and 40R and an upper wall portion 40A. The left and right seat back side panels 40L and 40R are, for example, shown in FIG. The uneven reinforcing rib as shown in FIG. 3B is repeatedly formed in the vehicle body width direction, and the upper edge portion is connected to the upper wall portion 40A.
The left and right seat back side panels 40L and 40R are erected on the front upper side (including the side part) of the left and right rear pillars 50 and the rear wheel house 20, respectively, and support the rear side of the seat. It is supposed to be.

  Further, when the seat back panel 40 is assembled to form a vehicle, the seat back panel 40 is located at the front portion of the trunk room 30 and functions as a partition wall that separates the living room from the trunk room 30 and the left and right seat back side panels 40L, The opening 41 surrounded by 40R, the upper wall 40A, and the floor panel 15 constitutes a trunk through.

  The rear pillar 50 is attached to the side part of the floor panel 15, the peripheral part of the rear wheel house 20, and the seat back panel 40 by spot welding, for example.

  The parcel panel 60 is a member that connects the left and right rear pillars 50 as described above, and the front edge portion is connected to the upper wall portion 40A of the seat back panel 40 by, for example, spot welding, so that the left and right sides of the rear vehicle body structure 10 are connected to each other. It is designed to span.

  As shown in FIG. 3, the reinforcing structure 70 is provided in the seat back panel 40, and includes a first reinforcing member 71, a second reinforcing member 72, and a connecting member corresponding to each of the seat back side panels 40 </ b> L and 40 </ b> R. 75A and 75B, and suppresses out-of-plane deformation of the seat back side panels 40L and 40R.

  The first reinforcing member 71 is formed of, for example, a rectangular high-tensile steel plate, and is connected to the left and right seat back side panels 40L and 40R from the room side of the seat back panel 40 using the connecting members 75A and 75B. ing.

  The connecting member 75A is made of, for example, a bolt, and connects the first reinforcing member 71 and the seat back side panels 40L and 40R at the upper part. The connecting member 75B includes the first reinforcing member 71 and the seat back side panel 40L, 40R is connected to the rear cross member 16 at the bottom. Instead of fastening and fixing the first reinforcing member 71 to the rear cross member 16, it may be joined by spot welding, arc welding, or the like.

  For example, the second reinforcing member 72 is formed by press-molding a rectangular high-tensile steel plate, and as shown in FIG. It has a curved shape erected in a state of being connected to the lower portions of the panels 40L, 40R, and reinforcing ribs made of irregularities are formed on the cross section perpendicular to the longitudinal direction.

The upper part of the second reinforcing member 72 is connected to the seat back side panels 40L and 40R by fastening members (not shown) such as bolts, and the lower part is connected to the seat back side panels 40L and 40R and the rear cross member 16 is connected. It is designed to be pinched.
In place of the fastening member, for example, the second reinforcing member 72 and the seat back side panels 40L and 40R may be attached by spot welding.

Moreover, the 2nd reinforcement member 72 is connected with the rear cross member 16 with the volt | bolt which is not illustrated, for example.
Whether or not the second reinforcing member 72 is fixed to the rear cross member 16 can be arbitrarily set. For example, it is preferable to fix the second reinforcing member 72 using a fastening member such as a bolt or a joining means such as spot welding. It is.

  According to the rear vehicle body structure 10 according to the first embodiment, the reinforcing structure 70 includes the rear cross member 16 with the seat back side panels 40L and 40R sandwiched between the first reinforcing member 71 and the second reinforcing member 72. Therefore, out-of-plane deformation of the seat back side panels 40L and 40R is suppressed, and the torsional rigidity can be improved.

  According to the rear vehicle body structure 10, when the reinforcing structure 70 is provided on the vehicle body structure (the vehicle body strength is maintained and the torsional rigidity is reduced by 50%) which is lightened by reducing the thickness of the steel plate by 30% on average. It was confirmed that the torsional rigidity can be improved by 3.72% by increasing the weight of 0.07 kg. As described above, the torsional rigidity can be greatly improved with a small increase in weight.

Next, a second embodiment of the present invention will be described with reference to FIG.
The rear vehicle body structure 11 according to the second embodiment differs from the first embodiment in that a reinforcing structure 80 is provided.
For example, as shown in FIG. 4A, the reinforcing structure 80 extends to the upper part of the seat back side panels 40L and 40R (for example, the upper end where the parcel panel 60 is located) instead of the second reinforcing member 72. The second reinforcing member 81 is provided. Since others are the same as those of the first embodiment, the same reference numerals are given and description thereof is omitted.

  According to the rear vehicle body structure 11 according to the second embodiment, since the second reinforcing member 81 extends to the upper ends of the seat back side panels 40L and 40R, the entire length of the seat back side panels 40L and 40R is extended. Out-of-plane deformation is suppressed, and as a result, the torsional rigidity of the vehicle body can be improved.

  According to the rear vehicle body structure 11, it was confirmed that the torsional rigidity can be improved by 4.99% by increasing the weight of 1.26 kg by providing the reinforcing structure 80. As described above, the torsional rigidity can be greatly improved.

Next, a third embodiment of the present invention will be described with reference to FIG.
The rear vehicle body structure 12 according to the third embodiment is different from the first embodiment in that a reinforcing structure 85 is provided.
Instead of the second reinforcing member 71, the reinforcing structure 85 is, for example, a second reinforcing member 86 having reinforcing ribs 87 extending rearward at both ends in the vehicle body width direction as shown in FIG. It has.

  According to the rear vehicle body structure 12 according to the third embodiment, since the ribs extending rearward of the vehicle body are formed on both sides of the second reinforcing member 86, a large section modulus of the second reinforcing member 86 is ensured. And torsional rigidity can be improved more efficiently.

  According to the rear vehicle body structure 12, it was confirmed that the torsional rigidity can be improved by 5.98% by providing the reinforcing structure 85 and increasing the weight by 1.43 kg. As described above, the torsional rigidity can be further improved.

Next, a fourth embodiment of the present invention will be described with reference to FIG.
The rear body structure 13 according to the fourth embodiment is different from the first embodiment in that a reinforcing structure 90 is provided.
Instead of the second reinforcing member 72, the reinforcing structure 90 is, for example, a lower side formed of a high-tensile steel plate by a sheet metal press curved backward and bent rearward of the rear cross member 16 to the front side. 16 is provided with a second reinforcing member 91 formed so as to be placed on the upper portion 16T.
The second reinforcing member 91 has a lower portion connected to the upper portion 16T of the rear cross member 16 by a fastening member (not shown) such as a bolt, and an upper side of the curved position by the fastening member 92. The reinforcing member 71 and the seat back side panels 40L and 40R are connected to each other. Since others are the same as those of the first embodiment, the same reference numerals are given and description thereof is omitted.

  According to the rear vehicle body structure 13 according to the fourth embodiment, the seat back side panels 40L and 40R are supported by the second reinforcing member 91 supported by the upper portion 16T of the rear cross member 16, so that an increase in weight is reduced. However, the out-of-plane deformation can be efficiently suppressed. As a result, the torsional rigidity can be improved efficiently.

  According to the rear vehicle body structure 13, it was confirmed that the torsional rigidity can be improved by 4.77% by providing the reinforcing structure 90 with a weight increase of 1.27 kg. As described above, the torsional rigidity can be improved efficiently.

Note that the present invention is not limited to the above-described embodiment, and various modifications can be made without departing from the spirit of the invention.
For example, the length with respect to the seat back side panels 40L and 40R according to the second reinforcing members 72, 81, 86, and 91 shown in the first to fourth embodiments, the shape of the reinforcing ribs, and the support on the rear cross member 16 These positions and methods can be used in various combinations.

In the first to fourth embodiments, the case where the seat back side panels 40L and 40R are formed by being connected to the left and right rear wheel houses 20 and the rear pillars 50 has been described. For example, FIG. Needless to say, the present invention can be applied to the seat back side panels 40L and 40R separated from the left and right rear wheel houses 20 and the rear pillars 50 as in the reinforcing structure 95 (95L and 95R) shown in FIG.
Whether the seat back side panels 40L and 40R are connected to one of the left and right rear wheel houses 20 and the rear pillar 50, and whether the upper part of the seat back side panels 40L and 40R is connected to the upper wall portion 40A. It can be appropriately selected whether to directly connect to the parcel panel 60.

Instead of the parcel panel 60, for example, the left and right rear pillars may be connected by a rear cross member other than the parcel panel 60, or a member having a cantilever needle structure that does not directly connect the left and right rear pillars 50 may be used. Good.
Further, instead of the seat back panel 40 in which the left and right seat back side panels 40L and 40R are connected by the upper wall portion 40A, the left and right seat back side panels 40L and 40R are not connected by the upper wall portion 40A. It may be used.

Moreover, in the said embodiment, although the case where a vehicle body was formed with high-tensile steel was demonstrated, a part or all of vehicle body structure may be formed with materials other than high-tensile steel.
Moreover, although the case where the whole vehicle body structure 1 consists of a monocoque body was demonstrated, you may apply to other vehicle body structures, such as having a frame structure in part, for example.

Moreover, in the said embodiment, although the case where the rear strut tower 25 was provided adjacent to the inner side of the rear wheel house 20 was demonstrated, the rear strut tower 25 is the upper side of the rear wheel house 20, for example, a rear wheel house. It may be formed inside or behind 20.
Needless to say, the rear vehicle body structures 10, 11, and 12 according to the present invention can be applied not only to automobiles equipped with an internal combustion engine, but also to hybrid cars, electric cars provided with electric motors on each wheel, and the like.

  Since the torsional rigidity of the automobile body structure can be improved efficiently, it can be used industrially.

DESCRIPTION OF SYMBOLS 1 Vehicle body structure 10, 11, 12, 13 Rear vehicle body structure 10R Rear axle center 15 Floor panel 16 Rear cross member 16T Upper part (rear cross member)
20 Rear wheel house 25 Rear strut tower 30 Trunk room 40 Seat back panel 40A Upper wall portion 40L, 40R Seat back side panel 50 Rear pillar 60 Parcel panel 70, 80, 85, 90 95 Reinforcement structure 71 First reinforcement member 75A, 75B Connection Member 72, 81, 86, 91 2nd reinforcement member

Claims (3)

Floor panels,
Rear wheel houses formed on left and right portions of the floor panel;
A rear strut tower provided corresponding to the rear wheel house,
Left and right rear pillars connected to each of the rear wheel houses;
A seat back side panel formed between the living room and the trunk room;
A rear cross member connecting the left and right rear pillars behind the seat back side panel;
A rear vehicle body structure comprising:
A first reinforcing member disposed on the room side of the seat back side panel;
A connecting member that connects the seat back side panel and the first reinforcing member;
A second reinforcing member disposed on the trunk room side of the seat back side panel,
The second reinforcing member is
A rear vehicle body structure characterized in that a lower portion is supported by the rear cross member and is supported with the seat back side panel and the rear cross member interposed therebetween . Floor panels,
Rear wheel houses formed on left and right portions of the floor panel;
A rear strut tower provided corresponding to the rear wheel house,
Left and right rear pillars connected to each of the rear wheel houses;
A seat back side panel formed between the living room and the trunk room;
A rear cross member connecting the left and right rear pillars behind the seat back side panel;
A rear vehicle body structure comprising:
A first reinforcing member disposed on the room side of the seat back side panel;
A connecting member that connects the seat back side panel and the first reinforcing member;
A second reinforcing member disposed on the trunk room side of the seat back side panel,
The second reinforcing member is
A rear vehicle body structure characterized in that a lower part is supported by the rear cross member, and abuts on an upper part of the rear cross member to support the seat back side panel . The rear vehicle body structure according to claim 1 or 2 ,
The second reinforcing member is
A rear vehicle body structure that extends to an upper end portion of the seat back side panel.

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