JP5132968B2 - Body frame structure - Google Patents

Description

  The present invention relates to a vehicle body frame structure disposed in front of a vehicle compartment and in a lower portion of the compartment.

As the body frame structure of the front part of the car body, in addition to the left and right upper frames located at the same height as the tops of the left and right front wheels, the left and right chassis members located at the same height as the floor part, the center of the front wheel There is known a structure in which left and right front side members extending in the longitudinal direction of the vehicle body are arranged at substantially the same height as the shaft (see, for example, Patent Document 1). An engine and a transmission are disposed inside the left and right front side members in the vehicle width direction. In such a frame structure, the front wheel may interfere with the front side member at the time of maximum steering, so that the front wheel can enter the vehicle width direction inner side than the front member portion in consideration of the improvement of the collision energy absorption performance and the steering angle. There has been provided a technique for forming a space so that a front member portion does not pass between a central region and an engine and a transmission (see, for example, Patent Document 2). The vehicle body frame structure is located above the center axis of the front wheel and extends from the front pillar lower to the front of the vehicle, and the lower member portion is located below the center axis of the front wheel and extends from the front end of the floor to the front of the vehicle. A coupling portion coupled in front of the front wheel, and a front member portion extending forward of the vehicle from the coupling portion. In such a vehicle body frame structure, the force input from the front of the vehicle body in the event of a collision or the like is distributed and input from the left and right front member portions to the upper member portion and the lower member portion.
Japanese Patent No. 2890938 JP 2006-143178 A

  However, the above-described body frame structure has the following problems. That is, in order to obtain higher collision energy absorption efficiency, a structure that further absorbs the energy that is dispersed vertically from the front member portion and transmitted to the upper member portion and the lower member portion is required. However, if a member for absorbing energy is added separately, weight reduction and layout freedom may be hindered.

  Accordingly, the present invention provides a frame structure with higher collision energy absorption efficiency without disturbing weight reduction and layout freedom by adopting a configuration in which the energy of the front frame portion is transmitted to the floor frame portion. Objective.

A vehicle body frame structure according to an embodiment of the present invention includes a left and right side sill that is disposed at a lower part of a vehicle compartment and extends from a front pillar lower disposed at both ends of the vehicle width direction to the vehicle body rear side, and on the inner side in the vehicle width direction than the side sill. A floor frame portion having left and right floor side members extending in the front-rear direction of the vehicle body, and disposed in front of the passenger compartment, positioned above the center axis of the front wheel, and forward and downward of the vehicle from the front pillar lower An upper member portion that is curved and extends toward the front, a lower member portion that is positioned below the center axis of the front wheel and that extends forward of the vehicle in front of the floor frame portion, and the upper member portion and the lower member portion that are coupled in front of each other A front frame portion configured to have a front member portion extending forward of the vehicle from the coupled portion,
A connecting member that is fixed to the upper member portion at the rear of the front member portion and connects the upper member portion and the floor frame portion, and the connecting member is a vehicle body longitudinal direction at the rear on the extension line of the front member portion. A front portion extending in the direction of the vehicle body, a rear portion extending in the longitudinal direction of the vehicle body continuously from the front end of the floor side member, and an intermediate portion extending obliquely from the front portion and continuing to the rear portion. In addition, the front end surface of the front portion is joined to the rear side wall surface of the protruding portion of the upper member portion behind the extension line of the front member portion, and connects the upper member portion and the front end portion of the floor side member. It is a member rear.

In the vehicle body frame structure according to one aspect of the present invention, the front member rear is an extruded member having a closed cross-sectional shape having a hollow portion continuous in the longitudinal direction, and the intermediate portion is connected to the vehicle via a curve from the front portion. It extends obliquely inward in the width direction and continues to the rear part via a curve.

  In the vehicle body frame structure according to one aspect of the present invention, the front member rear is an extruded member having a continuous cross-sectional shape in the longitudinal direction, and a front portion extending in the vehicle body front-rear direction on the rear side of the extension line of the front member portion; A rear portion that is continuous with the front end of the floor side member and an intermediate portion that extends obliquely from the front portion inward in the vehicle width direction and continues to the rear portion are integrally provided.

  In the vehicle body frame structure according to one aspect of the present invention, the floor frame portion extends from the lower part of the left and right front pillar lowers toward the inside in the vehicle width direction, and the vehicle width increases as the end surface on the inner side in the vehicle width direction moves rearward. A dash cross member lower that forms an inwardly inclined surface, and a front end surface of the front portion of the front member rear is joined to a rear side wall surface of a protruding portion protruding inward of the upper member portion; The wall surface is joined to the inner wall surface at the rear portion of the upper member portion, and the outer wall surface of the rear portion forms a slope toward the inside of the vehicle width toward the rear, and is joined to the inner end surface of the dash cross member lower, The rear end surface is joined to the vehicle width direction inner side portion of the front end surface of the floor side member, and the rear side wall surface of the dash cross member lower Characterized in that it is joined to the vehicle transverse direction outer side portion of the front end face of the floor side member.

  In the vehicle body frame structure according to one aspect of the present invention, the connection member is formed integrally with the front pillar lower by a die-cast material, and is an extension portion that connects the upper member portion and the front end portion of the side sill. Features.

  According to the above configuration, the present invention can provide a frame structure with higher collision energy absorption efficiency without hindering weight reduction and freedom of layout.

[First embodiment]
A vehicle body frame structure according to a first embodiment of the present invention will be described below with reference to FIGS. In addition, forward (front side), rear (rear side), left and right width directions are defined based on the traveling direction of the car, the direction toward the center of the width direction of the car is inward (inside), and from the center of the car to the width direction The spreading direction is the outside direction (outside). The direction in which gravity acts is the downward direction (lower side), and the direction against gravity is the upward direction (upper side). In the figure, arrows X, Y and Z indicate three orthogonal directions, arrow X indicates the front of the vehicle body, arrow Y indicates the vehicle width direction left side, and arrow Z indicates the vehicle body upward direction. Also, the description of the same configuration on the left and right is omitted as appropriate.

  FIG. 1 shows a part of a body frame structure of an automobile (vehicle) according to the present embodiment. As shown in FIGS. 1, 2, and 3, a cowl top 13 extending in the vehicle width direction and a dash cross member upper between left and right front pillar lowers 12 formed at the lower part of the left and right front pillar uppers 11, respectively. 14, a dash cross member lower 15 is provided. The cowl top 13 is disposed at the upper part of the front pillar lower 12 and is curved so that the center portion in the vehicle width direction is directed forward. The dash cross member upper 14 is disposed below the cowl top 13 and is curved so that the central portion in the vehicle width direction is downward. The dash cross member lower 15 is disposed below the dash cross member upper 14 and extends inward from the lower portion of the front pillar lower 12. The inner end surface 15a of the dash cross member lower 15 forms a slope that faces inward from the front to the rear. The end surface of the hollow member refers to the end surface of the outer peripheral portion around the hollow portion.

  Side sills 21 extend from the lower portions of the left and right front pillar lowers 12 toward the rear of the vehicle body. The rear end of the side sill 21 is positioned in front of the rear wheel (not shown). Inside the side sill 21, the floor side member 22 is connected to the inner end of the dash cross member lower 15 and extends toward the rear of the vehicle body. A backbone 23 extends in the longitudinal direction of the vehicle body at the center in the vehicle width direction.

  Various cross members 24, 25, 26 extending in the vehicle width direction are provided between the left and right side sills 21. The outer end surfaces of the dash cross member lower 15 and the various cross members 24, 25, and 26 are joined to the inner wall surfaces 21a of the left and right side sills 21 by welding or the like.

  The rear end portions of the floor side member 22 and the backbone 23 are joined to a cross member 26 disposed in front of the rear wheel. The lower surfaces of the various cross members 24, 25 and 26 and the upper surface of the floor side member 22 are joined by welding or the like at the intersecting portions. Further, the inner end surfaces of the cross members 24 and 25 are connected to the backbone 23 via the backbone side panel 27.

  The side sill 21, the floor side member 22 and the backbone 23 extending in the front-rear direction, the dash cross member lower 15 and the various cross members 24 to 26 extending in the vehicle width direction are combined with each other in a ladder shape, and the floor frame 20 Is configured. A floor panel (not shown) that forms the floor of the passenger compartment is fixed to the upper portion of the floor frame portion 20 by welding or the like.

  The various frame materials 13-15, 21-26, 36, 42, etc. constituting the floor frame portion 20 and the front frame portion 30, which will be described later, are made of an extruded member formed into an elongated shape from a light alloy casting such as an aluminum alloy, for example. The cross-sectional shape is, for example, a quadrangular shape having a hollow portion, and is continuous in the longitudinal direction with a constant closed cross-section. The curved cowl top 13 and the dash cross member upper 14 are configured to be bent and deformed as long as their cross-sectional shapes are continuous.

  The left and right front pillar lowers 12 connecting the lower end of the front pillar upper 11 and the end of the floor frame portion 20 in the vehicle width direction are made of a light alloy casting such as an aluminum die cast material. A front side member upper 31 (upper member portion) is provided so as to continue from the front end portion of the front pillar lower 12 so as to bend and extend forward and downward from the vehicle body above the center axis C of the front wheel W indicated by a broken line in FIG. It has been. The rear end surface of the front side member upper 31 and the front end surface of the front pillar lower 12 are joined by welding. The front side member upper 31 is made of a light alloy casting such as an aluminum die-cast material. A spring house 32 is integrally formed on the inner surface of the rear portion of the front side member upper 31 so as to protrude toward the inside of the vehicle body to form a protruding portion. A fender shield panel 33 protrudes inward and is integrally formed on the inner side surface of the front side member upper 31 in front of and below the spring house 32 to constitute a protruding portion.

  A front side member lower 34 (lower member portion) continuously extending from the vicinity of both outer ends of the dash cross member lower 15 toward the front of the vehicle body at a level substantially lower than the center axis C of the front wheel W and the floor frame portion 20. Is provided. The front side member lower 34 is made of a light alloy casting such as an aluminum die-cast material such that the left and right side portions 34a are curved inward in the vehicle width direction, are connected at portions close to each other, and are H-shaped in plan view. It is integrally formed. The front wheels W are arranged in the left and right spaces S formed below the front side member upper 31 and outside the curved portion of the front side member lower 34.

  The front end portion of the front side member upper 31 and the front end portion of the front side member lower 34 are coupled to each other by, for example, bolting at a coupling portion 35 disposed in front of the front wheel W. As shown in FIG. 2, the shape in the vicinity of the coupling portion 35 is Y-shaped in plan view. Front side members (front member portions) 36 extending toward the front of the vehicle body are provided in front of the left and right coupling portions 35, respectively. The front end portion of the coupling portion 35 and the rear end portion of the front side member 36 are fixed by welding or bolting.

  A crash box 39 that extends toward the front of the vehicle body is provided in front of the front side member 36. The front end portion of the front side member 36 and the rear end portion of the crash box 39 are fixed by welding or bolting via flange portions 40 and 41 provided respectively. The crash box 39 has a function of absorbing the collision energy by actively crushing the shaft when the vehicle collides at a low speed, and preventing a portion behind the crash box 39 from being damaged.

  A front bumper beam 42 extending in the vehicle width direction is provided between the front end portions of the left and right crash boxes 39. The front bumper beam 42 has a function of distributing collision energy to the left and right crash boxes 39 and the left and right frame members 31 such as the front side member upper 31 and the front side member lower 34 located behind the crash box 39.

  The front frame portion 30 of the vehicle body is configured by the cowl top 13, the dash cross member upper 14, the front side member upper 31, the front side member lower 34, the front side member 36, the front bumper beam 42, and the like.

A front member rear 50 is provided as a connecting portion for connecting the rear side wall surface 33a of the fender shield panel 33 as a protruding portion protruding inward from the front side member upper 31 and the front end portion of the floor side member 22. It has been. The front member rear 50 has a horizontal front part (front part) 51 extending substantially horizontally rearward from the front side member upper 31, and a slanting rear lower direction and a vehicle width direction through a gentle curve downward from the horizontal front part 51. An oblique intermediate portion (intermediate portion) 52 extending inward and a horizontal rear portion (rear portion) 53 extending rearward and horizontally inward in the vehicle width direction from the rear end of the oblique intermediate portion 52 are continuous. Are integrally formed. The front member rear 50 is obtained by extruding a light alloy lump such as an aluminum alloy. For example, the front member rear 50 is formed of an elongated extruded member in which a hollow cross section (closed cross-sectional shape) having a rectangular hollow portion is continuous in the longitudinal direction, and has a constant closed cross-sectional shape. Is configured to be bent within a continuous range.

The horizontal front portion 51 is disposed at the same position as the front side member 36 in the vehicle width direction and the height direction, and extends in the front-rear direction so as to continue on the extension line of the front side member 36 via the front side member upper 31. . The front end surface 51a of the horizontal front 51 is bonded to the side wall surface 33a after the fender shield panel 33 as a protrusion amount projecting inwardly from the front side member upper. An outer wall surface 51b of the horizontal front portion 51 is formed so as to follow the shape of the inner wall surface 31a of the rear end portion of the front side member upper 31, and is welded to the lower side of the spring house 32 and behind the fender shield panel 33 by welding. It is joined to the inner wall surface 31 a of the member upper 31.

  As shown in FIGS. 2, 4, and 5, the outer wall surface 53 a of the horizontal rear portion 53 is formed along the inclined shape of the inner end surface 15 a of the dash cross member lower 15, and is formed on the inner end surface 15 a of the dash cross member lower 15. They are joined by welding. The rear end surface 53b of the horizontal rear portion 53 is joined to the inner portion of the front end surface of the floor side member 22 by welding. The rear side wall surface 15b of the dash cross member lower 15 is joined to the outer portion of the front end surface of the floor side member 22 by welding. That is, the three members of the dash cross member lower 15, the floor side member 22, and the front member rear 50 are welded at the welded portions shown in the drawing and joined to each other.

  In the frame structure 1 configured as described above, the impact force input from the front part is distributed to the left and right by the front bumper beam 42, absorbed by deformation of the crash box 39 and transmitted to the front side member 36. The impact force input to the front side member 36 is distributed and transmitted to the front side member upper 31 and the front side member lower 34 and is transmitted to the floor side member 22 through the front member rear 50. At this time, the impact energy is absorbed by the buckling deformation of the front member rear 50 formed of the integrally formed extrusion material.

  The vehicle body frame structure 1 according to the present embodiment has the following effects. That is, the front frame 30 and the floor frame 20 are connected by the front member rear 50 connected from the front side member upper 31 to the floor side member 22 and the dash cross member lower 15, and the impact force from the front is applied to the floor frame 20. Therefore, the absorption efficiency of the impact force is improved. Since the front member rear 50, the floor side member 22, and the dash cross member lower 15 are welded to each other at the side wall surface and the end surface, the collision energy can be efficiently dispersed.

  Further, since the front member rear 50 includes a horizontal front portion 51 extending on an extension line of the front side member 36 and is configured to be continuously connected to the floor side member 22 with a constant closed cross section, the efficiency is improved. Can transmit power well. Since the floor frame portion 20, the front frame portion 30, and the front member rear 50 are made of an aluminum extrusion molded product having a constant closed cross-sectional shape, it is possible to reduce the weight while ensuring high strength, and at the time of a collision, Since the shaft is crushed and deformed in order from the rear to the rear, a high shock absorption amount can be secured without greatly deforming the passenger compartment.

  By providing the front side member upper 31 having the functions of the upper frame and the front side member above the central axis C of the front wheel W, and providing the front side member lower 34 having the functions of the chassis member and the front side member on the inside, The layout can be such that the front side member 36 does not pass between the center region of the front wheels W and the engine and transmission. Therefore, in addition to the upper frame and the chassis member, a front side member having a large cross-sectional area is arranged at the height of the central axis C of the front wheel W so as to extend in the vehicle front-rear direction, so that the front wheel W The turning angle at the time of maximum steering can be set large. Further, since the coupling portion 35 is Y-shaped and the front end portion of the front side member upper 31 and the front end portion of the front side member lower 34, whose center line of the cross section is shifted in the vehicle width direction, are coupled, The collision energy absorption performance at the time can be secured. The front member rear 50 also ensures a turning angle at the time of maximum steering of the front wheels W.

[Second Embodiment]
Next, a frame structure according to a second embodiment of the present invention will be described with reference to FIGS. In addition, since it is the same as that of the said 1st Embodiment about structures other than a connection member, description is abbreviate | omitted.

  In the frame structure 2 according to the present embodiment, as a connection member, the front pillar lower 12 is formed so as to extend from the rear portion of the front side member upper 31 to the front end portion of the side sill 21 on the extension line of the front side member 36. An extending portion 60 is provided. The extending portion 60 is formed integrally with the front pillar lower 12 and is disposed so as to be continuous with the rear end of the spring house 32 that protrudes inwardly at the rear portion of the front side member upper 31. The extension portion 60 extends below the front side member upper 31 so as to enter the inside of the vehicle body, and a space S for the front wheel W is secured outside the extension portion 60. The front side member upper 31 having the extending portion 60 and the front pillar lower 12 are joined together so that a space for a front wheel is secured outside the lower portion of the front side member upper 31 from the rear end of the front side member 36. The side sill 21 continues through the fender shield panel 33, the spring house 32, and the extending portion 60.

  In the vehicle body frame structure 2 having such a configuration, the collision force input to the front of the vehicle body is distributed and transmitted to the front side member upper 31, the front side member lower 34, and the extending portion 60 as indicated by arrows. . The force input to the extending portion 60 is transmitted to the side sill 21 as indicated by an arrow.

  Also in this embodiment, the same effect as the frame structure 1 according to the first embodiment described above can be obtained.

  In carrying out the present invention, the constituent elements of the present invention such as the specific shapes of the case members and the cross-sectional shapes of various frame members can be variously changed without departing from the spirit of the invention.

The perspective view which shows the vehicle body frame structure concerning 1st Embodiment of this invention. The top view which shows the same vehicle body frame structure. The side view which shows the same vehicle body frame structure. The perspective view which shows the connection structure of the front member rear concerning the embodiment. The side view which shows the connection structure of the front member rear concerning the embodiment. The perspective view which shows the vehicle body frame structure concerning 2nd Embodiment of this invention. The side view which shows the same vehicle body frame structure.

Explanation of symbols

11 ... Front pillar, 12 ... Front pillar lower, 13 ... Cowl top,
14 ... Dash cross member upper, 15 ... Dash cross member lower,
15a ... inner end face, 15b ... rear side wall face, 20 ... floor frame part, 21 ... side sill,
21a ... inner wall surface, 22 ... floor side member, 30 ... front frame part,
31 ... Front side member upper, 31a ... Inner wall surface, 32 ... Spring house,
33 ... Fender shield panel, 33a ... Rear side wall surface,
34 ... front side member lower, 34a ... side part, 35 ... coupling part,
36 ... front member part, 50 ... front member rear, 51 ... horizontal front part,
51a ... front end face, 51b ... outer wall surface, 52 ... oblique middle part, 53 ... horizontal rear part,
53a ... Outer wall surface, 53b ... Rear end surface, 60 ... Extension part.

Claims (4)

Left and right side sills that are arranged at the lower part of the vehicle compartment and extend from the front pillar lowers arranged at both ends in the vehicle width direction to the rear of the vehicle body, and left and right floor side members that extend in the vehicle longitudinal direction inside the vehicle side in the vehicle width direction A floor frame portion configured to have,
An upper member portion disposed in front of the passenger compartment and positioned above the center axis of the front wheel and extending curvedly from the front pillar lower toward the vehicle front and downward, and positioned below the center axis of the front wheel, A front frame portion configured to include a lower member portion that extends forward of the vehicle in front of the frame portion, and a front member portion that extends forward of the vehicle from a joint portion in which the upper member portion and the lower member portion are coupled in front of each other. When,
A connection member fixed to the upper member portion at the rear of the front member portion and connecting the upper member portion and the floor frame portion; and
The connecting member has a front portion extending in the longitudinal direction of the vehicle body on the rear side of the extension line of the front member portion, a rear portion extending in the longitudinal direction of the vehicle body continuously from the front end of the floor side member, and extending obliquely from the front portion to the rear portion. A continuous intermediate portion, and integrally formed continuously, and the front end surface of the front portion is joined to the rear side wall surface of the protruding portion of the upper member portion at the rear on the extension line of the front member portion, A vehicle body frame structure that is a front member rear that connects the upper member portion and a front end portion of the floor side member.   The front member rear is an extruded member having a closed cross-sectional shape having a hollow portion that is continuous in the longitudinal direction, and the intermediate portion obliquely extends inward in the vehicle width direction from the front portion via the curve. The vehicle body frame structure according to claim 1, wherein the body frame structure is continuous with the rear portion. The floor frame portion includes a dash cross member lower that extends from the lower part of the left and right front pillar lowers toward the inside in the vehicle width direction and forms a slope toward the vehicle width inside as the end surface on the vehicle width direction inner side goes rearward. Have
Wherein the front portion of the outer wall surface of the front member rear are joined to the rear of the upper member portion,
The outer wall surface of the rear part forms a slope toward the vehicle width inner side as it goes rearward, and is joined to the inner end surface of the dash cross member lower,
The rear end surface of the rear part is joined to the vehicle width direction inner side portion of the front end surface of the floor side member,
The vehicle body frame structure according to claim 2, wherein a rear side wall surface of the dash cross member lower is joined to an outer portion in a vehicle width direction of a front end surface of the floor side member.   2. The vehicle body frame structure according to claim 1, wherein the connection member is formed integrally with the front pillar lower, and is an extension portion that connects the upper member portion and a front end portion of the side sill.

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