JP4462630B2 - Lower body structure - Google Patents

Description

  The present invention relates to a vehicle body lower structure including a lower side sill and a center pillar included in a side wall of a passenger compartment, a floor frame and a floor cross member included in a floor of the passenger compartment, and a floor panel.

For the purpose of increasing the strength of the floor of the passenger compartment, an outrigger is attached to the vehicle so as to be orthogonal to a side sill disposed at the lower portion of the side wall of the passenger compartment (see, for example, Patent Document 1).
Japanese Patent Laid-Open No. 7-164846 (page 3, FIG. 1)

Patent document 1 is demonstrated based on the following figure.
FIG. 8 is a diagram for explaining a basic configuration of a conventional technique. In a conventional rear suspension link mounting structure 301, a rear side member 303 is joined to a side sill 302, and brackets 304 and 305 are mounted to the rear side member 303. The recess 307 for attaching the outrigger 306 to the bracket 305 is formed, and the attachment strength of the outrigger 306 is improved by the recess 307, and the outrigger 306 does not peel off from the bracket 305. Direction) can be transmitted to the side sill 302, and the support rigidity can be increased.

  However, the rear suspension link mounting portion structure 301 of Patent Document 1 has a problem that it is difficult to absorb the force applied to the side sill 302, for example, the impact applied to the side surface of the vehicle.

  It is an object of the present invention to provide a vehicle body lower structure that absorbs a load applied to a side surface of a vehicle and suppresses a protruding amount into a vehicle compartment when the load is absorbed.

In the invention according to claim 1, the lower side sill included in the side wall of the passenger compartment and the center pillar erected on the side sill, the floor frame which is included in the passenger compartment floor and is long in the front-rear direction, and the floor frame are crossed. The floor cross member is connected to the lower part of the center pillar via an outrigger and a floor frame , and the outrigger is U-shaped in cross section, and the bottom side. A bag structure is formed with a floor panel attached to an opening facing the bottom side, and formed on the side line that continues to the bottom side, so that the cross-sectional area of the bag structure gradually increases from the side sill toward the floor frame. A first inclined portion, a horizontal portion, and a second inclined portion are formed, and a first fragile portion that protrudes into the bag structure is formed at a boundary portion between the horizontal portion and the second inclined portion. It is, and a second inclined portion, characterized in that a second fragile portion are formed in a pair of ridge forming a U-shaped cross-section.

  In the invention which concerns on Claim 2, a 2nd weak part is a recessed part formed in the ridgeline part which is a boundary of a base and a side.

  In the invention according to claim 3, the outrigger is characterized in that a seat mounting bracket is disposed above the horizontal portion.

In the invention according to claim 1, the floor cross member is connected to the lower part of the center pillar via the outrigger and the floor frame, and the outrigger is U-shaped in cross section, and is formed of a bottom side and a side continuous to the bottom side. In addition, a bag structure is formed with the floor panel attached to the opening facing the bottom side, and the first inclined portion, the horizontal portion, and the second portion are formed on the bottom side so that the cross-sectional area of the bag structure gradually increases from the side sill to the floor frame. An inclined portion is formed, and a first fragile portion protruding into the bag structure is formed at a boundary portion between the horizontal portion and the second inclined portion, and the second inclined portion and a pair of ridge lines forming a U-shaped cross section Since the second fragile portion is formed, when a load is applied to the side surface of the vehicle, the center pillar is deformed, and the lower portion of the center pillar enters the vehicle interior. In this case, the outrigger has an advantage that the outer end coupled to the side sill having a small cross-sectional area starts to be deformed and is sequentially deformed toward the floor frame to absorb the load.

  Further, following the deformation near the outer end, the first fragile portion is deformed as a starting point, and following the deformation of the first fragile portion, the second fragile portion is deformed as a starting point. At that time, since the horizontal part that is the same as the direction of the force is difficult to deform, it moves in the direction of the force as it is, reduces the upward protrusion, and the deformed part starting from the first fragile part is the first part below the floor panel. Since the portion that has entered the substantially triangular bag structure of the two inclined portions and is deformed starting from the second weakened portion has formed the second weakened portion on the ridgeline, the substantially triangular bag of the second inclined portion below the floor panel Go deep into the structure. Therefore, as a whole, there is an advantage that the amount of protrusion into the vehicle interior can be reduced.

  Furthermore, since the outrigger is connected to the floor frame, the cross-sectional area of the bag structure further gradually increases from the side sill toward the floor frame. The amount of external force (load) applied to the center pillar can be increased, and the strength against the load generated during traveling can be ensured.

  In the invention which concerns on Claim 2, since a 2nd weak part is a recessed part formed in the ridgeline part which is a boundary of a base and a side, after changing a 1st weak part preferentially, a floor panel There exists an advantage that a 2nd inclination part can be deform | transformed more reliably before this, and a load can be absorbed more reliably.

  In the invention according to claim 3, since the seat mounting bracket is disposed above the horizontal portion of the outrigger, the seat can be fixed at a position where the amount of protrusion to the inside of the passenger compartment is small. When a load is applied to the side surface, the upward movement amount of the seat can be reduced.

The best mode for carrying out the present invention will be described below with reference to the accompanying drawings. The drawings are viewed in the direction of the reference numerals.
FIG. 1 is a perspective view of a lower body structure of the present invention.
The vehicle body lower structure 11 includes left and right side sills 15 and 16 below the left and right side bodies 13 and 14 included in the side wall of the passenger compartment 12, left and right floor frames 17 and 18 included in the floor of the passenger compartment 12, and left and right side frames. Between the first floor cross member 21 connected between the side sills 15 and 16, the second floor cross member 22 connected between the left and right floor frames 17 and 18, and between the left floor frame 17 and the left side sill 15. A left outrigger 23 attached to the right floor frame 18, a right outrigger 24 attached between the right side sill 16, a left front side frame 25 connected to the left floor frame 17, and a right floor frame. 18, a right front side frame 26 connected to 18, and a floor panel 27. 31 are those employed in the vehicle body 32.

  In the figure, 33 is the engine room, 34 is the left center pillar standing on the left side sill 15, 35 is the right center pillar standing on the right side sill 16, and 36 is between the left and right floor frames 17,18. And a vertical frame that is supported at one end by the first floor cross member 21.

The left front side frame 25 has a rear end 41 connected to a front end 42 of the left floor frame 17.
The right front side frame 26 has a rear end 43 connected to a front end 44 of the right floor frame 18.

The front side 46 of the left side sill 15 is joined to the front end 42 of the left floor frame 17 by a front outrigger 47.
The right side sill 16 has a front end 48 joined to a front end 44 of the right floor frame 18 by a front outrigger 51.

  The first floor cross member 21 has a front portion 55 (similar to the seat 54) of the front seat 55 of the driver seat 53 (see FIG. 2) and a front passenger seat 56 (same as the seat 54) disposed on the left. Is attached to the left side sill 15, the right end 58 is joined to the right side sill 16, and seat front mounting portions 62 and 62 having female threads are formed on the upper portion 61. The lower part 63 is attached to the upper surface of the panel 27, the left side of the lower part 63 is attached to the left floor frame 17 below the floor panel 27, and the right side of the lower part 63 is attached to the right floor frame 18 below the floor panel 27. .

  The second floor cross member 22 has a left end 67 attached to the cross portion 66 of the left floor frame 17 joined to the lower portion of the left center pillar 34 via the left outrigger 23, and the right center trigger 35 has the right outrigger 24. The right end 71 is attached to the cross portion 68 of the right floor frame 18 connected via the seat, the seat rear attachment portion 72 having a female screw is attached to the left end 67, and the seat rear attachment portion 73 having a female screw is attached to the right end 71. Is installed.

The left outrigger 23 is formed with a seat rear mounting bracket 75 which is a seat mounting bracket having a female thread.
The right outrigger 24 is formed with a seat rear mounting bracket 76 which is a seat mounting bracket having a female thread.

  FIG. 2 is a side view of the lower body structure of the present invention and shows the relationship between the seat 54 of the driver's seat 53, the left floor frame 17, and the first floor cross member 21. This will be described with reference to FIG.

In the first floor cross member 21, the front portion 55 of the seat 54 is attached to the seat front attachment portions 62 and 62, and supports the front portion 55 of the seat 54. Similarly, the passenger seat 56 is supported.
The second floor cross member 22 also has a rear portion 78 of the seat 54 attached to the seat rear attachment portion 72 through the floor panel 27 and supports the rear portion 78 of the seat 54. Similarly, the passenger seat 56 is supported.

  The left outrigger 23 supports a rear portion 78 of the seat 54 by attaching a rear portion 78 of the seat 54 to the seat rear portion mounting bracket 75 through the floor panel 27. Similarly, the passenger seat 56 is supported.

FIG. 3 is a cross-sectional view taken along line 3-3 of FIG. 1 and is a cross-sectional view of the right outrigger 24 of the vehicle body lower structure 11.
FIG. 4 is a perspective view of a right outrigger provided in the lower body structure of the present invention.

  The right outrigger 24 is attached between the right side sill 16 and the right floor frame 18, and the floor panel 27 and the rear part 78 of the seat are attached to the upper part, and a first side (bottom side) 151 facing downward is provided. And a second side (side side) 152 that is continuous with the first side (bottom side) 151 and faces forward, and a third side that faces the second side (side side) 152 and is continuous with the first side (base side) 151. A side (side) 153, an outer end 154 formed on one side and coupled to the right side sill 16, an inner end 155 formed on the other side and coupled to the right floor frame 18, and a first side An opening 156 facing the (bottom side) 151 is formed, and the floor panel 27 is attached to the edge flange 157 of the opening 156, whereby a substantially triangular bag structure 158 is formed.

  Further, in the right outrigger 24, the first side (bottom side) 151 is formed so that the cross-sectional area perpendicular to the longitudinal direction of the bag structure 158 (the direction of the arrow b1) gradually increases from the outer end 154 toward the inner end 155. A first inclined portion 161 connected to the end 154 is formed, a horizontal portion 162 is formed continuous to the first inclined portion 161, a second inclined portion 164 is formed continuous to the horizontal portion 162, and above the horizontal portion 162. A rear seat mounting bracket 75 is attached to the opening 156.

The horizontal part 162 is a substantially horizontal part, and may be inclined at an angle within an allowable range with respect to the horizontal line.
The first inclined portion 161 is inclined downward with respect to the floor panel 27.
The second inclined portion 164 is inclined downward with respect to the floor panel 27.

  The rear seat mounting bracket 75 includes a fixing portion 166 to which a rear portion (same as the rear portion 78) of the passenger seat 56 (similar to the seat 54) is fixed, a nut 167 attached to the fixing portion 166, and a fixing portion 166. The rib portions 168 and 168 are formed, and a welding allowance 171 is formed on the rib portion 168.

FIG. 5 is a view taken in the direction of arrow 5 in FIG. 1 and shows a state when the right outrigger 24 is looked up from below. This will be described with reference to FIGS.
Further, the right outrigger 24 has a first fragile portion 173 formed at a boundary portion 172 between the horizontal portion 162 and the second inclined portion 164, and a boundary between the first side (bottom side) 151 and the second side (side side) 152. A front ridge line portion 174 is formed with a predetermined bending radius R (see FIG. 6), and is rearward with a predetermined bending radius R (see FIG. 6) at the boundary between the first side (bottom side) 151 and the third side (side side) 153. A ridge line portion 175 is formed, and concave second weak portions 176 are formed on the front and rear ridge line portions 174 and 175 located on the second inclined portion 164 of the ridge line portions 174 and 175, respectively.

  The 1st weak part 173 is the hollow formed in the center of the 2nd inclination part 164 with the depth h (refer FIG. 3) by extending the horizontal part 162. FIG.

FIG. 6 is a cross-sectional view taken along line 6-6 of FIG. 3 and shows a cross section of the second fragile portion 176 of the right outrigger 24.
The second fragile portion 176 has a desired depth from the front ridge line portion 174 perpendicular to a line passing through the central angle δ that bisects the inner angle θf formed by the first side (base) 151 and the second side (side) 152. It is a dent (concave part) formed of Hn. Compared with the intensity | strength of the site | part which has arrange | positioned the 1st weak part 173 (refer FIG. 3), the intensity | strength of the site | part which has arrange | positioned the 2nd weak part 176 is large.

  The second fragile portion 176 is also disposed on the rear ridge line portion 175, and is orthogonal to a line passing through the central angle δ that bisects the internal angle θf formed by the first side (base) 151 and the third side (side) 153. It is a dent (concave part) formed at a desired depth Hn from the rear ridge line part 175.

Next, the operation of the vehicle body lower structure 11 of the present invention will be described.
FIGS. 7A to 7C are schematic views for explaining a mechanism for absorbing the load applied to the side surface of the vehicle by the lower body structure of the present invention. 1 and 3 will be used together for explanation. The side sill and the center pillar are shown removed, and the parts to be joined by spot welding are shown separately.

  In (a), in the vehicle body lower structure 11 of the vehicle 31, the right outrigger 24 is connected to the lower portion of the right center pillar 35 and attached between the right side sill 16 and the right floor frame 18. . A load F (see also FIG. 1) starts to be applied as indicated by an arrow b2 at the center of the right side surface of the vehicle 31, that is, the position where the right center pillar 35 is disposed.

  In (b), when a load F is applied to the right side surface of the vehicle 31, the force is transmitted from the right side sill 16 to the right outrigger 24. Therefore, the right outrigger 24 starts to deform from the vicinity of the outer end 154 having the smallest cross-sectional area, The load can be absorbed.

  Further, when the load is larger, the right outrigger 24 starts to deform from the first fragile portion 173 following the deformation near the outer end 154, and can absorb a larger load from the side surface. At that time, the portion deformed starting from the first fragile portion 173 enters the substantially triangular bag structure 158 below the floor panel 27 as indicated by an arrow b3, so that the protruding amount B into the passenger compartment 12 is reduced. be able to.

  In (c), when the load is even larger, the deformation starts from the second fragile portion 176 following the deformation of the first fragile portion 173, so that a larger load can be absorbed. At that time, the portion deformed starting from the second fragile portion 176 enters the substantially triangular bag structure 158 below the floor panel 27 as indicated by an arrow b4, so that the protruding amount B into the vehicle compartment 12 is reduced. be able to.

  That is, in the outrigger 24, the strength (cross-sectional area) is gradually increased so as to be gradually deformed from the portion (outer end 154) on the side receiving the load toward the floor frame 18, so the load applied to the side surface of the vehicle 31 Can be absorbed, and strength against a load generated during traveling can be ensured. Further, when the load is absorbed, entry into the vehicle compartment can be suppressed.

  Since the outrigger 24 is provided with a seat rear mounting bracket 76, the seat can be fixed at a position where the protruding amount B inward of the passenger compartment is small, and when the load F is applied to the right side surface of the vehicle 31, The amount of movement upward of the seat can be reduced.

  In the vehicle body lower structure 11, when a load is applied to the left side surface of the vehicle 31 to which the left outrigger 23 is attached, the same effect as when a load is applied to the right side surface of the vehicle 31 by the left outrigger 23 is exhibited. To do.

  The vehicle body lower part structure of the present invention is suitable for a four-wheeled vehicle.

The perspective view of the lower body structure of the present invention Side view of the lower body structure of the present invention 3-3 sectional view of FIG. The perspective view of the right outrigger with which the lower body structure of the present invention is provided 1 arrow view of FIG. 6-6 sectional view of FIG. The schematic diagram explaining the mechanism in which the vehicle body lower part structure of this invention absorbs the load added to the side surface of a vehicle The figure explaining the basic composition of conventional technology

Explanation of symbols

  DESCRIPTION OF SYMBOLS 11 ... Vehicle body lower structure, 12 ... Vehicle compartment, 15, 16 ... Side sill, 17, 18 ... Floor frame, 21 ... First floor cross member, 22 ... Second floor cross member, 23 ... Left outrigger, 24 ... Right outrigger, 27 ... floor panel, 34, 35 ... center pillar, 75, 76 ... seat mounting bracket (seat rear mounting bracket), 151 ... bottom (first side), 152 ... side (second side), 153 ... side ( 3rd side), 156 ... opening, 158 ... bag structure, 161 ... first inclined part, 162 ... horizontal part, 164 ... second inclined part, 172 ... boundary part, 173 ... first fragile part, 174 ... front ridge line part 175: Rear ridge line portion, 176: Second weakened portion.

Claims (3)

The lower side sill included in the side wall of the passenger compartment, the center pillar erected on the side sill, the floor frame that is included in the passenger compartment floor and that crosses the floor frame that is long in the front-rear direction, and the floor In the lower body structure with panels,
The floor cross member is connected to a lower part of a center pillar via an outrigger and the floor frame ,
The outrigger is a U-shaped section, and bottom, while being formed at the side edges connected to the bottom, the bag structure is formed by said floor panel mounted in an opening facing the bottom, said from the sill A first inclined portion, a horizontal portion, and a second inclined portion are formed at the bottom so that a cross-sectional area of the bag structure gradually increases toward the floor frame, and the bag structure is formed at a boundary portion between the horizontal portion and the second inclined portion. A vehicle body lower structure characterized in that a first fragile portion projecting inward is formed, a second fragile portion is formed on a pair of ridge lines which form a second inclined portion and form the U-shaped cross section.   The vehicle body lower part structure according to claim 1, wherein the second fragile part is a concave part formed in a ridge part which is a boundary between the base and the side.   The lower body structure according to claim 1, wherein a seat mounting bracket is disposed above the horizontal portion of the outrigger.

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