JPH05294258A - Automobile body structure - Google Patents

Abstract

PURPOSE:To heghten the tensile rigidity and dent resistance of the face without increasing weight. CONSTITUTION:A hollow molded member 8 made of synthetic resin (polypropylene, for instance) is provided inside a side still 5 of closed cross-sectional structure in such a way as to be in almost contact with the inner peripheral surface of the side sill 5. The tensile rigidity and dent resistance of the face of closed cross-sectional structure are heightened by the hollow molded member 8 without causing the increase of weight.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a vehicle body structure for an automobile in which a body panel member is joined to form a closed cross-section structure.

[0002]

2. Description of the Related Art Conventionally, for example, as in a front pillar of an automobile body, a body panel member is joined to enhance rigidity to form a closed cross-section structure, and a foaming agent is provided inside the closed cross-section structure. What is filled is known (see, for example, JP-A-61-205109).

[0003]

By the way, in such a structure in which the foaming agent is filled, since the filling material has bubbles, there are portions where the vehicle body panel member is supported by the foamed resin and portions where it is not supported. Therefore, when a concentrated load acts, the surface pressure on the resin increases at the acting portion, so that the strength of the foamed resin to be filled is required to be increased. That is, there are problems in surface rigidity and dent resistance. In addition to that, since the whole closed-section structure has a solid structure filled with the foaming agent, it causes an increase in weight.

The present invention provides a vehicle body structure for an automobile having improved surface tension rigidity and dent resistance without increasing the weight.

[0005]

The present invention is premised on a vehicle body structure of an automobile in which a body panel member is joined to form a closed sectional structure.

According to a first aspect of the present invention, a hollow molding member made of synthetic resin is provided inside the closed cross-section structure so as to substantially contact the inner peripheral surface of the vehicle body panel member.

According to the second aspect of the present invention, at least one of the vehicle body panel member and the hollow molded member is provided with a groove portion through which the filler flows between the both members.

According to the third aspect of the present invention, the vehicle body panel member is configured to form a closed cross-section structure by welding the joining flange portion, and the joining flange is provided in the hollow molding member near the joining flange portion. A built-up portion that can be melted by the welding heat of the portion is formed in advance.

[0009]

According to the first aspect of the present invention, the hollow molded member surely enhances the dent resistance and the surface tension rigidity without increasing the weight as compared with the conventional structure in which the foaming agent is filled. Strength is improved by preventing the collapse of the cross section.

According to the second aspect of the present invention, the filling material is surely spread between the body panel member and the hollow molding member by being guided by the groove portion.

According to the third aspect of the present invention, when spot welding the joining flange portion, the build-up portion of the hollow molded member only melts by welding heat, and no hole is formed in the hollow molded member. ..

[0012]

Embodiments of the present invention will now be described in detail with reference to the drawings.

In FIG. 1 showing a schematic structure of an automobile body, reference numeral 1 is an automobile body having a front pillar-2, a center pillar 3 and a rear pillar 4 which extend in the vertical direction,
The lower end of the center pillar 3 is connected to the side sill 5.

The side sill 5 has a closed cross-section structure in which a side sill inner 6 as a vehicle body panel member and a side sill outer 7 are joined and extends in the vehicle front-rear direction, and a synthetic resin having a shape corresponding to the inner peripheral surface shape. A hollow molding member 8 made of polypropylene (for example, polypropylene) is arranged in a state of being closely adhered to the inside. The side sill inner 6 and the side sill outer 7 are formed with joint flange portions 6b, 6c, 7b, 7c above and below the inner body 6a and the outer body 7a, respectively.
The b, 6c, and 7c are joined by spot welding to form a closed cross-section structure.

To assemble the above-described structure, as shown in FIG. 3, adhesive 9a, 9b (or sealer) is uniformly applied to the inner peripheral surfaces of the side sill inner 6 and the side sill outer 7 in advance when the vehicle body is assembled. Then, the hollow molded member 8 is sandwiched between the side sill inner 6 and the side sill outer 7. After that, the joint flange portions 6b, 7b, 6c,
7c is spot welded. Reference numeral 10 denotes a floor panel, the flange portion 10a of which is spot-welded to the joint flange portion 6c of the side sill inner 6.

Also, since the lower side portion of the side sill inner 6 easily rusts, as shown in FIG.
An injection hole 6d is formed in the side hole, and the side sill inner 6 and the side sill outer 7 and the hollow forming member 8 are formed so that the electrodeposition liquid injected from the injection hole 6d can be easily spread over the whole.
A gap 11 is formed between and. Then, after the electrodeposition liquid is injected, a sealer is injected and heated to be cured to eliminate the gap 11.

Further, as shown in FIG. 5, a structural adhesive (so-called welt bond), which is electrically conductive to some extent and which is adhesively hardened during baking coating, is applied between the joint flange portions 6b and 7b, and then the flange portion is applied. When spot welding between 6b and 7b, the hollow molding member 8A is provided with a recess 8a in advance, the recess 8a is provided with a structural adhesive 12, and the joining flanges 6b and 7b are joined together to form the adhesive 12 Can be spread between the joint flange portions 6b and 7b to ensure efficient adhesion, and
In order to prevent the adhesive from dripping or flowing into the welding surface, a relatively viscous adhesive is used to form a recess 6e in the joint flange portion 6b as shown in FIG. 6
The adhesive 12 may be accumulated in e.

Further, the hollow molding member 8 is made of synthetic resin,
Since the heat resistance is poor and the thermal conductivity is low, the welding flanges 6b and 7b are welded by the welding heat when spot welding.
In order to prevent the temperature in the vicinity from being increased and thereby the hollow molded member 8 to be perforated, the hollow molded member 8 is prevented.
It is also possible to prevent the perforation by forming a built-up portion 8b that is melted by welding heat in advance. Specifically, the hollow molded member 8 has a wall thickness of about 2 mm, and a built-up portion 8 of about 4 mm.
b may be formed.

In order to facilitate the flow of the electrodeposition liquid and the sealer between the hollow molding member 8 and the side sill 5, as shown in FIG.
Alternatively, a linear groove portion 8d extending in the longitudinal direction may be formed, and the electrodeposition liquid and the sealer may be made to flow entirely between the hollow molding member 8 and the side sill 5 through the groove portions 8c and 8d.

Further, as shown in FIG. 8, it is possible to efficiently enhance the reinforcing effect by making the inside of the hollow molding member 8 into a solid foamed portion 8e by using a foaming agent only at a portion to be partially reinforced.

In the above embodiment, the hollow molding member is separately molded in advance and then provided in the side sill. However, as shown in FIG.
And the inner surface of the side sill 5 is subjected to electrodeposition coating, and then blow molding means 13 is applied to the side sill 5 by blow molding.
It is also possible to directly form the hollow molding member 8 in the side sill 5 so as to follow the inner surface shape.

Although the above embodiment has been described with respect to the example applied to the side sill constituting the closed cross-section structure, the present invention is not limited thereto, and may be applied to other closed cross-section structures such as front pillars, center pillars, rear pillars and the like. It can also be applied to.

[0023]

As described above, according to the invention of claim 1, since the hollow molding member is arranged inside the closed cross-section structure, as compared with the conventional structure in which the foaming agent is filled in the closed cross-section structure. As a result, the hollow molded member can surely improve the dent resistance and the surface tension rigidity without increasing the weight, and the proof strength can be increased by preventing the collapse of the cross section.

According to the second aspect of the present invention, the filling material such as the electrodeposition liquid and the sealer is guided to the groove portion, and the filling material surely flows between the hollow molding member and the closed cross-section structure.

According to the third aspect of the present invention, at the time of spot welding the joint flange portion, only the overlay portion of the hollow molded member is melted by the welding heat. Therefore, other portions are not melted, and the hollow molded member has a hole. Prevented from opening.

[Brief description of drawings]

FIG. 1 is a side view of a vehicle body of an automobile.

FIG. 2 is a sectional view of the side sill of FIG.

FIG. 3 is an explanatory diagram of an assembling method.

FIG. 4 is an explanatory diagram of injection of an electrodeposition liquid or the like.

FIG. 5 is an explanatory diagram when a structural adhesive is used.

FIG. 6 is an explanatory diagram of another example using a structural adhesive.

FIG. 7 is an explanatory diagram of an example in which a built-up portion is provided.

FIG. 8 is an explanatory view of an example in which a hollow molded member is partially reinforced.

FIG. 9 is a perspective view of an embodiment in which a groove is provided in a hollow molded member.

FIG. 10 is an explanatory diagram of another assembling method.

[Explanation of symbols]

 1 Body 5 Side sill 6 Side sill Inner (body panel member) 7 Side sill outer (body panel member) 8 Hollow molded member 8b Overlay part 8c, 8d Groove part

Claims (3)

[Claims] 1. A vehicle body structure of an automobile in which a body panel member is joined to form a closed cross-section structure, wherein a hollow molded member made of synthetic resin is provided inside the body structure. A vehicle body structure characterized in that it is provided so as to substantially contact the peripheral surface. 2. A vehicle body structure according to claim 1, wherein at least one of the vehicle body panel member and the hollow molded member is provided with a groove portion through which a filling material flows between the both members. 3. The vehicle body panel member is configured to form a closed cross-section structure by welding the joint flange portion, and the hollow molded member near the joint flange portion is melted by the welding heat of the joint flange portion. The vehicle body structure of the automobile according to claim 1 or 2, wherein a possible built-up portion is formed in advance.