JPH101073A - Lower body structure - Google Patents

Abstract

(57) [Summary] [PROBLEMS] To suppress vibration of a rear floor panel having a spare tire as a mass when a spare tire is suspended and held on the lower surface of a rear floor panel, and to prevent vibration noise from being transmitted to a passenger compartment. A lower vehicle body structure of a type in which a rear cross member (12) is provided on a lower surface of a rear floor panel (11) in a vehicle width direction and a spare tire (20) is suspended and held behind the rear cross member (12). Rear cross member 1 from the rear end of the vehicle
2, a front end portion of the reinforcing member 13 is bent downward along the rear cross member 12, and a hinge portion of a spare tire carrier 16 is provided at a lower end portion of the bent portion 15. 17 is set.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a lower vehicle body structure of a type in which a rear cross member is provided on a lower surface of a rear floor panel in a vehicle width direction and a spare tire is suspended and held behind the rear cross member.

[0002]

2. Description of the Related Art Conventionally, as a lower body structure of this type, for example, a structure as shown in FIG. 3 is known (a similar structure is disclosed in Japanese Patent Application Laid-Open No. 5-31912). This is a system in which a spare tire 3 is suspended and held by using a rear cross member 2 arranged in the vehicle width direction on the lower surface of a rear floor panel 1, and a hanger bracket 5 is bolted to a rear surface 4 of the rear cross member 2 with bolts 6. The hinge portion 8 of the spare tire carrier 7 is set at the lower end of the hanger bracket 5, and a hook 9 for holding the spare tire carrier 7 is disposed at the rear end of the rear floor panel 1. The spare tire 3 is directly in contact with the lower surface of the rear floor panel 1 via a patch plate or the like, and is suspended and held by the spare tire carrier 7.

[0003]

However, in the above-described conventional lower vehicle body structure, since the heavy spare tire 3 is suspended and held in contact with the lower surface of the rear floor panel 1, the spare tire is held. There is a problem that the rear floor panel 1 having a low rigidity is caused to vibrate up and down due to the mass 3 and the vibration noise is transmitted to the vehicle interior. In the lower body structure described above, the hanger bracket 5 is fixed to the rear surface 4 of the rear cross member 2 with bolts 6. Therefore, it is difficult to secure a space for inserting the air gun, and layout of the hanger bracket 5 is restricted.

Therefore, the present invention suppresses the vibration of the rear floor panel when the spare tire is suspended and held below the rear floor panel, thereby preventing the transmission of vibration noise to the passenger compartment, and is subject to layout restrictions. It is not to be.

[0005]

That is, in a lower vehicle body structure according to the present invention, a rear cross member is provided on a lower surface of a rear floor panel in a vehicle width direction, and a spare tire is suspended and held behind the rear cross member. In the lower body structure of this type, a reinforcing member extending in the front-rear direction from the rear end of the vehicle to the rear cross member is disposed on the lower surface of the rear floor panel, and the front end of the reinforcing member is bent downward along the rear cross member. And a hinge portion of a spare tire carrier is set at a lower end portion of the bent portion.

Further, in the lower vehicle body structure according to the present invention, the bent portion at the front end of the reinforcing member is bent from a rear portion of the lower surface of the rear floor panel below the rear cross member and extends to the lower end of the rear surface of the rear cross member. A closed cross section is formed together with the cross member and the lower surface of the rear floor panel.

Further, the lower vehicle body structure according to the present invention is characterized in that the spare tire holding portion of the bent portion has a shape substantially along the sectional shape of the spare tire.

[0008]

Embodiments of the present invention will be described below in detail with reference to the accompanying drawings. In the embodiment of the present invention shown in FIGS. 1 and 2, a reinforcing member 13 extending in the front-rear direction from the rear end of the vehicle to the rear cross member 12 is provided on the lower surface of the rear floor panel 11 near the center of the vehicle width. Has been established. The front end of the reinforcing member 13 is bent downward along the vertical wall 14 of the rear cross member 12, and the tip of the bent portion 15 projects from the lower end of the rear cross member 12. A hinge portion 17 of a spare tire carrier 16 is set at the tip of the bent portion 15. On the other hand, the spare tire carrier 1
A hook 18 for suspending and holding the hook 6 is provided.

The reinforcing member 13 has flanges 19 on both sides.
a, a member having a substantially U-shaped cross section and having a rear floor panel 11 and a rear cross member 1 during manufacture of the vehicle body.
The two rear surfaces 12a are integrated with the vehicle body by spot welding the flanges 19a and 19b. Here, the bent portion 15 is bent from a rear portion of the rear cross member 12 provided on the lower surface of the rear floor panel 11 to extend to the lower end of the rear surface 12a of the rear cross member 12, and the rear cross member 12 and the rear floor panel 11 A closed section D is formed together with the lower surface of the spare tire 2, and a portion of the bent portion 15 where the spare tire 20 abuts and is held is the spare tire 2.
0 is formed in a substantially arc shape along the cross-sectional shape. In such a structure, the spare tire 20 is suspended and held by the spare tire carrier 16 in a state where the spare tire 20 is directly abutted against the reinforcing member 13.

In FIG. 1, reference numerals 21a and 21b
Are rear side members disposed on the right and left sides of the rear floor panel 11.

Therefore, in such a lower vehicle body structure, the rear floor panel 11 is integrally connected to the high-rigidity reinforcing member 13, and the rear tire panel 11 is suspended and held in a state where the spare tire 20 is directly abutted against the reinforcing member 13. Therefore, the vibration of the rear floor panel 11 with the spare tire 20 as a mass is suppressed by the reinforcing member 13, and as a result, the vibration noise of the rear floor panel 11 is reduced. Further, since the spare tire 20 is not in contact with the rear floor panel 11, it can prevent rust on the rear floor panel 11, and can prevent expensive coating such as cation coating in a separate process like a conventional hanger bracket of another part. It is not necessary to perform rust treatment, and it is only necessary to perform rust-proof painting on the reinforcing member 13 together with the vehicle body, so that costs and man-hours can be reduced. Further, the reinforcing member 13 and the rear cross member 1
2 and the bent part 1 against rear collision etc.
5 firmly holds the spare tire 20, so that the spare tire 20 can be prevented from moving forward with the collision.

The bent portion 15 is provided on the rear floor panel 1.
Since the closed cross section D is formed together with the rear surface 12a of the rear cross member 1 and the rear cross member 12, not only the rigidity of the vehicle body can be improved, but also the rigidity of holding the spare tire 20 can be improved. Since the portion has a shape substantially along the cross-sectional shape of the spare tire 20, the spare tire 20 holding the spare tire 20 does not rattle, and the vibration amount of the rear floor panel 11 is further reduced. Become. In the above embodiment, the case where the reinforcing member 13 is disposed near the center of the vehicle width of the rear floor panel 11 has been described. However, the reinforcing member 13 is not necessarily required to be located near the center. The thickness of the reinforcing member 13 and the size of the cross-sectional shape are appropriately selected.

[0013]

As described above, according to the first aspect of the present invention, the rear floor panel is integrally joined to the rigid reinforcing member, and the spare tire is directly hit against this reinforcing member. Since the rear floor panel is suspended and held in the state, the vibration of the rear floor panel with the spare tire as a mass is suppressed by the reinforcing member, and as a result, the vibration noise of the rear floor panel is reduced. Also, since the spare tire is not in contact with the rear floor panel, it can prevent rust on the rear floor panel, and there is no need to perform expensive rust prevention treatment in a separate process like the conventional hanger bracket of another part, Cost and man-hour can be reduced. Furthermore, since the reinforcing member and the rear cross member are coupled, the bent portion firmly holds the spare tire against a rear collision or the like, so that the spare tire can be prevented from moving forward with the collision.

According to the second aspect of the present invention, the closed cross section formed by the bent portion and the rear surface of the rear floor panel and the rear cross member improves not only the rigidity of the vehicle body but also the rigidity of holding the spare tire. The vibration noise of the rear floor panel is reduced, and the ability to prevent the spare tire from moving forward in the event of a rear collision is further improved.

According to the third aspect of the present invention, since the portion of the bent portion that contacts the spare tire has a shape substantially along the sectional shape of the spare tire, the spare tire is held while the spare tire is held. The tires do not rattle,
The vibration noise of the rear floor panel can be further reduced.

[Brief description of the drawings]

FIG. 1 is a perspective view showing one embodiment of a lower vehicle body structure according to the present invention.

FIG. 2 is a sectional view showing one embodiment of a lower vehicle body structure according to the present invention.

FIG. 3 is a sectional view showing an example of a conventional lower vehicle body structure.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 11 Rear floor panel 12 Rear cross member 12a Rear 13 Reinforcement member 15 Bending part 16 Spare tire carrier 17 Hinge part 20 Spare tire D Closed section

Claims (3)

[Claims] 1. A lower vehicle body structure of a type in which a rear cross member is provided on a lower surface of a rear floor panel in a vehicle width direction and a spare tire is hung and held behind the rear cross member, wherein a vehicle is mounted on a lower surface of the rear floor panel. A reinforcing member extending in the front-rear direction from the rear end to the rear cross member. The front end of the reinforcing member is bent downward along the rear cross member, and a hinge of a spare tire carrier is provided at a lower end of the bent portion. Lower body structure characterized by the setting of parts. 2. A bending portion at a front end of the reinforcing member is bent from a rear portion of a lower surface of a rear floor panel from a rear cross member and is extended to a lower end of a rear surface of the rear cross member.
The lower vehicle body structure according to claim 1, wherein a closed cross section is formed with the rear cross member and the lower surface of the rear floor panel. 3. The lower vehicle body structure according to claim 1, wherein a spare tire holding portion of the bent portion has a shape substantially along a sectional shape of the spare tire.