JP2009248805A - Vehicle front body structure of automobile - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a vehicle front body structure of an automobile for providing an improvement of strength against a collision without accompanying any heavy weight formation while expanding a compartment space. <P>SOLUTION: This front vehicle body structure is constructed such that rear ends of a pair of right and left wheel house upper members 6 constituting the upper part of a wheel house 15 are connected to each of front peeler lowers 3, an instrument panel lower 10 is arranged between both front peeler lowers 3l, 3r and an instrument panel across member 11 is connected to the lower part of the instrument panel lower 10 to form a closed sectional surface, wherein the wheel house upper member 6 is constituted by an upper horizontal part 6a extending from the upper part of the front peeler lower 3 in a forward direction in a substantial horizontal manner, a lower horizontal part 6b extending from the lower part of the front peeler lower 3 in a forward direction in a substantial horizontal manner and a slant part 6c extending from the front part of the lower horizontal part 6b in a forward slant upper direction and connected to the upper horizontal part 6a, and both ends of the instrument panel lower cross member 11 are connected to the front ends of both the right and left lower horizontal parts 6b. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a front body structure of an automobile, and relates to a technique for realizing an improvement in strength against a collision by load distribution while expanding a cabin space.

  An automobile having a monocoque structure (hereinafter referred to as a monocoque car) has a body produced by press-molding a thin steel plate to produce a large number of body panels and skeletal members and then joining them by spot welding or the like. In such a monocoque vehicle, a pair of left and right upper members are extended from the upper end of the front pillar lower to the front of the vehicle body, and the outer edge of the damper base in the vehicle width direction is joined to the upper member and the upper portion of the wheel house is configured. Some have adopted a body structure.

In order to support a large stress load and improve strength and rigidity, a reinforcement pillar lower is attached to the inner surface of the lower part of the hinge part of the front pillar lower, and a dash side panel is attached to the reinforcement pillar lower, and the front pillar is attached. Reinforcement that extends forward with respect to the reinforcement and the front pillar lower in the vehicle body with the wheel house upper member (reinforcement, cowl side and reinforcement, engine compartment panel) attached to the outer surface of the upper hinge part of the lower A side body structure in which a portion is formed and welded to a wheel house upper member (reinforcement cowl side) has been proposed (see Patent Document 1).
JP 2001-260941 A

  However, in the vehicle body structure having the above-described configuration, the left and right front pillar lowers are not connected by the cross member, so that the wheel house upper member is supported only by the front pillar lower and has low support rigidity. In order to increase the support rigidity of the wheel house upper member, it is necessary to increase the plate thickness of the member or increase the thickness of the front pillar lower, which causes a problem that the weight of the vehicle body increases.

  SUMMARY OF THE INVENTION The present invention has been made in view of such a background. An automobile body that realizes an improvement in strength against a collision by dispersing an input load without increasing the weight of the passenger compartment while increasing the cabin space. The purpose is to provide a structure.

  In order to solve the above problems, the present invention provides a pair of left and right front pillar lowers, a pair of left and right wheel house upper members whose rear ends are joined to the front pillar lowers and constitute an upper part of the front wheel house, In a vehicle front body structure including a dashboard lower disposed between pillar lowers and a dashboard lower cross member joined to a lower portion of the dashboard lower to form a closed cross section, the wheel house upper member includes An upper horizontal portion that extends substantially horizontally forward from the top of the front pillar lower, a lower horizontal portion that extends substantially horizontally forward from the lower portion of the front pillar lower, and a diagonally upward front from the front of the lower horizontal portion And an inclined portion joined to the upper horizontal portion, and both ends of the dash lower cross member are Serial configured to be joined to the front end of both the lower horizontal section (claim 1).

  In the front vehicle body structure of an automobile having the above configuration, the inclined portion is formed in a closed cross section by a front pillar inner that constitutes the front pillar lower (Claim 2), or the dash lower cross member of the lower horizontal portion. A stiffener may be attached to the joint position (claim 3).

  According to the present invention, the collision load input from the front end of the wheel house upper member includes a load path from the upper horizontal portion to the front pillar lower and the front pillar upper, and a dash lower cross that forms a closed cross section from the inclined portion to the lower horizontal portion. Since the load is distributed to the member or the side sill, the vehicle body strength against a collision is improved. Further, since the dash lower cross member is disposed in front of the front pillar lower, the vehicle interior space can be widened. Further, the support rigidity can be increased by connecting the wheel house upper member to both the dash lower cross member and the front pillar lower as a truss structure without narrowing the passenger compartment space.

  Further, since the inclined portion is formed in a closed cross section by the front pillar inner, the formation of the inclined portion and the joining of the dash lower cross member can be performed by spot welding, and the manufacture becomes easy.

  On the other hand, by attaching the stiffener to the joining position with the dash lower cross member in the lower horizontal portion, it is possible to increase the strength against load distribution to the dash lower cross member and efficiently distribute the load.

  Hereinafter, with reference to the drawings, an embodiment of a vehicle front body structure to which the present invention is applied will be described in detail. In the present embodiment, the present invention is applied to the body of an automobile adopting a monocoque structure. Since the skeletal structure of the body 1 has a substantially bilaterally symmetric structure, in the description, the subscripts 1 or r indicating the left and right are respectively added to the numerals of the members or parts arranged on the left and right of the body 1. For example, the left wheel house upper member 6l and the right wheel house upper member 6r are referred to as the wheel house upper member 6 when collectively referred to.

<< Configuration of Embodiment >>
1 is a perspective view of a front body skeleton structure according to the embodiment, FIG. 2 is a left side view of the front body skeleton structure according to the embodiment, and FIG. 3 is a sectional view taken along line III-III in FIG. 4 shows a cross-sectional view taken along line IV-IV in FIG. As shown in FIG. 1, the body 1 of the embodiment includes a pair of left and right front side frames 2 l and 2 r that are disposed at the front of the vehicle body and extend in the front-rear direction, and rear portions of both front side frames 2. A pair of left and right front pillar lowers 3l, 3r extending vertically in the lateral direction, and a pair of left and right wheel house upper members 61l whose front ends are joined to the bulkhead upper frame 7 and whose rear ends are joined to both front pillar lowers 3. , 6r.

  Both front pillar lowers 3 are joined at their lower ends to left and right side sills 16l, 16r, and at the upper ends, a pair of left and right front pillar uppers 4l, 4r extending diagonally upward and rearward are both front pillar lowers 3 And is integrally formed. Left and right bulkhead side stays 5 l, 5 r extending vertically are joined to the front ends of both front side frames 2, their upper ends are joined to the bulkhead upper frame 7, and their lower ends are connected by a front lower cross member 8. ing.

  Further, the upper ends of both front pillar lowers 3 are connected to each other in the vehicle width direction by a dashboard upper 9. A dashboard lower 10 is suspended below the dashboard upper 9 between the two front pillar lowers 3 to define a vehicle compartment 21 and an engine room 22. A dashboard lower cross member 11 having a U-shaped cross-section projecting forward is joined to the lower portion of the dashboard lower 10 along the lower edge to form a cross member having a closed cross section together with the dashboard lower 10. .

  A pair of left and right damper housings 12l and 12r, whose upper and lower portions are joined to the wheel house upper member 6 and the front side frame 2, respectively, in the vehicle width direction inner side in the vicinity of the center of the left and right wheel house upper members 6 in the front-rear direction. is set up. Damper bases 13l and 13r for supporting the load of the front wheels are integrally formed on the upper surface of the damper housing 12, respectively. Behind both damper housings 12 are wheel house rears 14l and 14r (shown only on the right side). These damper housings 12, damper base 13, wheel house upper member 6, wheel house rear 14 and the like constitute a wheel house 15. Has been.

  As shown in FIG. 2, the wheel house upper member 6 includes an upper horizontal portion 6 a that extends substantially horizontally forward from the upper end of the front pillar lower 3, and an upper horizontal portion that extends forward from the lower portion of the front pillar lower 3. A lower horizontal portion 6b that is shorter than 6a and extends substantially horizontally; and an inclined portion 6c that extends obliquely forward and upward from the front upper edge of the lower horizontal portion 6b and is joined to the upper horizontal portion 6a. ing. The upper horizontal portion 6a, the lower horizontal portion 6b, and the inclined portion 6c all have a closed cross section and form a substantially triangular truss structure together with the front pillar lower 3.

  As shown in FIG. 3, the front pillar lower 3 is composed of a front pillar outer 3o disposed on the outer side in the vehicle width direction and a front pillar inner 3i disposed on the inner side in the vehicle width direction. In the closed section of the front pillar lower 3, a front pillar lower stiffener 17 having a door hinge mounting nut 18 is joined so as to be in surface contact with the front pillar outer 3o, thereby improving the door mounting strength. ing.

  As shown in FIG. 4, the front pillar inner 3i extends in a vertically suspended state from the front joint portion with the front pillar outer 3o by joining a plurality of plate members. It also serves as a part of the inner member of the upper member 6. The wheel house upper member 6 forms a closed cross section by joining the upper member outer 6o to the front pillar inner 3i. The front pillar inner 3i is joined to the substantially triangular opening surrounded by the upper member outer 6o and the front pillar outer 3o so as to reinforce the truss structure.

  As shown in FIG. 3, a dash lower cross member 11 is joined to the front end of the lower horizontal portion 6 b of the wheel house upper member 6. In the lower horizontal portion 6b, a stiffener 19 joined to the outer and inner (front pillar inner 3i and upper member outer 6o) of the lower horizontal portion 6b is disposed on the same plane as the dashboard lower 10. Yes.

<< Assembly Procedure for Front Body Structure According to Embodiment >>
Next, a procedure for assembling the front vehicle body structure according to the embodiment will be described. FIG. 5 is a perspective view showing the left end portion of the dash lower cross member 11, FIG. 6 is a perspective view showing a disassembled state of the wheel house upper member 6, and FIG. 7 shows the front pillar lower 3 of the wheel house upper member 6. FIG. 8 is a perspective view showing a joined state of the dash lower cross member 11 to the wheel house upper member 6.

  As shown in FIG. 5, the dash lower cross member 11 is provided with a joining flange 11a at the upper and lower rear ends of the U-shaped cross section with the rear open, and spot welding is performed at a welding point a on the joining flange 11a. It is joined to the dashboard lower 10. At both ends in the vehicle width direction of the dash lower cross member 11, there are joint flanges 11 b that become spot welding points when joined to the front pillar inner 3 i (see FIG. 6). It is formed on each of the front surface and the lower surface.

  As shown in FIG. 6, the upper member outer 6o is joined to the front pillar outer 3o and the front pillar inner 3i by spot welding in a state where the stiffener 19 is installed in the lower horizontal portion 6b. As shown in FIG. 7, the upper member outer 6o is joined to the front pillar outer 3o by spot welding at the welding point b, and is joined to the front pillar inner 3i by spot welding at the welding point c. The

  As shown in FIG. 8, the upper member outer 6o is provided at its lower end with a lower end surface member 20 that is joined by spot welding at a welding point d and extends substantially horizontally to form the lower surface of the lower horizontal portion 6b. Yes. A joining flange 20a is suspended inside the lower end surface member 20 in the vehicle width direction, and the upper member outer 6o is joined to the front pillar inner 3i also by spot welding at a welding point e on the joining flange 20a.

<< Effects of Embodiment >>
With reference to FIG. 9, the effect in the body 1 of this embodiment is demonstrated. FIG. 9 shows the front body frame structure, the white arrow indicates the flow of the collision load input from the bulkhead upper frame 7, and the black arrow indicates the collision load input from the front lower cross member 8 and the bulkhead side stay 5. The flow is shown.

  When the automobile according to the embodiment causes a frontal collision, the collision load input from the front lower cross member 8 and the bulkhead side stay 5 is the lower horizontal portion of the front side frame 2, the dash lower cross member 11, and the wheel house upper member 6. 6b is transmitted to the side sill 16 in order. On the other hand, most of the collision load input to the bulkhead upper frame 7 is transmitted to the front pillar lower 3 and the front pillar upper 4 through the upper horizontal portion 6a of the wheel house upper member 6, and a part thereof is inclined portion 6c. To the side sill 16 via the lower horizontal portion 6b.

  Thus, according to the front body structure according to the present embodiment, the collision load input from the front end of the wheel house upper member 6 is a load path from the upper horizontal portion 6a to the front pillar lower 3 and the front pillar upper 4. Since the load is distributed to the load path from the inclined portion 6c to the lower horizontal portion 6b and the side sill 16, the vehicle body strength against the collision is improved. Further, the collision load distributed to the inclined portion 6c can be distributed not only to the side sill 16 but also to the dash lower cross member 11 having a closed cross section in the case of an oblique collision.

  And since the dash lower cross member 11 is arrange | positioned ahead of the front pillar lower 3, the space of the compartment 21 can be taken widely. Further, the support rigidity is increased by connecting the wheel house upper member 6 to both the dash lower cross member 11 and the front pillar lower 3 as a truss structure without narrowing the passenger compartment space.

  And in this embodiment, since the inclined part 6c is formed in a closed cross section by the front pillar inner 3i, it becomes possible to perform the formation of the inclined part 6c and the joining of the dash lower cross member 11 by spot welding. It has become easy.

  On the other hand, since the stiffener 19 is attached to the position where the lower horizontal portion 6b is joined to the dash lower cross member 11, strength against load distribution to the dash lower cross member 11 and load distribution from the dash lower cross member 11 is increased. Efficient load distribution is possible.

  Although the description of the specific embodiment is finished as above, the present invention is not limited to the above embodiment and can be widely modified. For example, although the present invention is applied to the body of an SUV, the above embodiment can be applied to all types of automobiles such as hatchbacks and sedans. In addition, specific configurations of various members and the like can be changed as appropriate without departing from the spirit of the present invention.

Perspective view of front body frame structure Left side view of the front body frame structure III-III sectional view in FIG. IV-IV sectional view in Fig. 2 Assembly explanatory diagram showing the main part of the front body structure Assembly explanatory diagram showing the main part of the front body structure Assembly explanatory diagram showing the main part of the front body structure Assembly explanatory diagram showing the main part of the front body structure Action diagram of front body frame structure

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Body 2 Front side frame 3 Front pillar lower 3o Front pillar outer 3i Front pillar inner 4 Front pillar upper 6 Wheel house upper member 6a Upper horizontal part 6b Lower horizontal part 6c Inclined part 6o Upper member outer 10 Dashboard lower 11 Dash lower cross Member 12 Damper housing 15 Wheel house 16 Side sill 21 Car compartment 22 Engine room

Claims (3)

A pair of left and right front pillar lowers,
A rear end is joined to the front pillar lower, and a pair of left and right wheel house upper members constituting the upper part of the front wheel house,
A dashboard lower disposed between the two front pillar lowers;
A dash lower cross member joined to the lower part of the dashboard lower and forming a closed cross section;
The wheel house upper member includes an upper horizontal portion that extends substantially horizontally forward from the upper portion of the front pillar lower, a lower horizontal portion that extends substantially horizontally forward from the lower portion of the front pillar lower, and the lower horizontal portion. An inclined portion that extends obliquely upward and forward from the front portion of the portion, and is joined to the upper horizontal portion,
A front body structure of an automobile, wherein both ends of the dash lower cross member are joined to front ends of the lower horizontal portions.   2. The front body structure of an automobile according to claim 1, wherein the inclined portion is formed in a closed cross section by a front pillar inner that constitutes the front pillar lower.   The front body structure of an automobile according to claim 1 or 2, wherein a stiffener is attached at a position where the lower horizontal part is joined to the dash lower cross member.

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