JP6112695B2 - Auto body structure - Google Patents

Description

  The present invention relates to a vehicle body structure for an automobile that supports a rear suspension component on a CFRP vehicle body.

  Japanese Patent Application Laid-Open No. 2004-228667 discloses a metal chassis provided with spring struts for elastically supporting front and rear axles, and CFRP bodies attached to the spring struts with bolts.

  The FRP body cross member is placed in front of the rear partition, a metal bracket is fixed so that the rear partition is sandwiched between the cross member, and the fuel tank is supported by this bracket. It is known from document 2.

US Patent Publication No. US2013 / 076069 Japanese Unexamined Patent Publication No. 2010-64696

  By the way, since the thing described in the said patent document 1 has a heavy metal chassis, there existed a problem that there was a limit in weight reduction even if a body was made from CFRP.

  In addition, in the above-mentioned Patent Document 2, the fuel tank can be supported by a metal bracket, but when the suspension damper is supported by the metal bracket, an excessive load is input from the damper. The FRP vehicle body could be damaged.

  The present invention has been made in view of the above-described circumstances, and an object thereof is to prevent the destruction of a CFRP vehicle body caused by a large load input from a rear suspension component with a lightweight structure.

  In order to achieve the above object, according to the present invention, there is provided a vehicle body structure for supporting a rear suspension component on a CFRP vehicle body, wherein the vehicle body structure includes a fragile portion between the vehicle body and the rear suspension component. The mount member is plastically deformed when an excessive load that does not cause destruction of the vehicle body is input to the vehicle body from the rear suspension component. A body structure is proposed.

  According to the present invention, in addition to the first feature, a vehicle body structure for an automobile is proposed in which the vehicle body is a rear damper support member and the rear suspension part is a rear damper. The

  According to the present invention, in addition to the second feature, the upper end of the rear damper support member is joined to an extension obtained by extending the upper end of the rear pillar rearward, and the lower surface of the step portion formed on the rear damper support member. A vehicle body structure for an automobile according to a third feature is proposed in which the mount member is supported and the upper surface of the step portion of the rear damper support member is connected to the extension portion via a connecting member.

  According to the invention, in addition to the third feature, the lower part of the CFRP vehicle body includes a vehicle body floor, left and right side sills extending in the front-rear direction along the vehicle width direction outer end of the vehicle body floor, and the left and right sides. Left and right front pillar lowers standing from the front end of the side sill, a dash panel lower connecting the left and right front pillar lowers to join the front end of the vehicle body floor, and left and right rear pillars standing from the rear end of the left and right side sills And a rear partition wall that connects the left and right rear pillars and joins to the rear end of the vehicle body floor, an outer end in the vehicle width direction of the rear floor that extends rearward from the rear end of the vehicle body floor, and the extension portion. The left and right rear pillars including the left and right rear damper support members are connected to each other, and the rear floor, the rear partition wall, and the left and right rear damper support members define a cargo compartment. Vehicle body structure is proposed to that was the fourth feature.

  According to the present invention, in addition to the fourth feature, there is proposed a vehicle body structure for an automobile, wherein the vehicle body floor is a hollow member made up of an under floor panel and an upper floor panel.

  According to the invention, in addition to the fourth or fifth feature, the vehicle body floor includes a protruding portion that protrudes outward in the vehicle width direction from the outer end in the vehicle width direction of the side sill, and at least within the protruding portion. A vehicle body structure for an automobile according to a sixth feature is proposed in which an energy absorbing member is disposed, and an outer end in the vehicle width direction of the protruding portion and an outer end in the vehicle width direction of the side sill are connected by a connecting member.

  According to the invention, in addition to any one of the fourth to sixth features, the rear partition wall is formed on the upper surface of the rear floor, the inner surface in the vehicle width direction of the rear damper support member, and the lower surface of the rear pillar. A vehicle body structure having a seventh feature of joining is proposed.

  According to the invention, in addition to any one of the fourth to seventh features, the rear partition that is a hollow member made of an outer skin and an inner skin is integrated with a rear par shell that extends rearward from the upper end thereof. A vehicle body structure for an automobile is proposed in which the outer skin and the inner skin are joined to each other at the bent portion at the front end of the rear par shell.

  According to the invention, in addition to any one of the fourth to eighth features, the rear floor includes left and right rear side frames, and the rear damper support member connects the rear pillar and the rear side frame. A vehicle body structure having a ninth feature is proposed.

  According to the present invention, in addition to the first feature, there is proposed a vehicle body structure for an automobile characterized in that the vehicle body is a side sill and the rear suspension component is a suspension arm.

  According to the invention, in addition to the tenth feature, the side sill extending in the front-rear direction along the vehicle width direction outer end of the CFRP vehicle body floor, the front pillar lower standing from the front end of the side sill, A vehicle body structure for an automobile according to an eleventh feature is proposed in which a rear pillar rising from a rear end of the side sill is formed in a U shape in a side view.

  According to the invention, in addition to the eleventh feature, the vehicle body floor is a hollow member obtained by joining the joining flange of the under floor panel and the joining flange of the upper floor panel. A vehicle body structure is proposed.

  According to the invention, in addition to the twelfth feature, the mount member may be attached to a nut embedded in a rear end portion of the side sill with a joining flange joining the under floor panel and the upper floor panel. A vehicle body structure of an automobile characterized by being fastened by a bolt to be screwed is proposed.

  According to the invention, in addition to the thirteenth feature, the mount member is cut out from an extruded material made of an aluminum alloy having a constant cross section in the longitudinal direction, and a bottom wall is formed with a bolt hole through which the bolt passes. A pair of side walls standing parallel to each other from the bottom wall, and a pair of reinforcing walls obliquely connecting the bottom wall and the pair of side walls, and a mounting hole for the suspension arm on the tip side of the side wall A vehicle body structure for an automobile according to a fourteenth feature is proposed in which the fragile portion is formed between the mounting hole and the reinforcing wall.

  According to the invention, in addition to any one of the tenth to fourteenth features, the vehicle body floor includes a protruding portion that protrudes outward in the vehicle width direction from the outer end in the vehicle width direction of the side sill, and at least A vehicle body structure for an automobile according to the fifteenth feature is proposed, wherein an energy absorbing member is disposed in the protruding portion, and an outer end in the vehicle width direction of the protruding portion and an outer end in the vehicle width direction of the side sill are connected by a connecting member. Is done.

  According to the invention, in addition to the first feature, the vehicle body is a CFRP frame of a rear side frame, the rear suspension part is a damper spring, and the front surface and the upper surface of the mount member are made of the CFRP. The front surface of the recess and the front surface of the recess of the CFRP frame are inclined from the front lower side to the rear upper side, respectively, and the mount member is predetermined from the damper spring. A vehicle body structure for an automobile is proposed, which is provided with the fragile portion that plastically deforms when a load greater than the value is input.

  According to the present invention, in addition to the sixteenth feature, there is proposed a vehicle body structure for a motor vehicle according to a seventeenth feature, wherein the CFRP frame is integrally continuous with a rear floor made of CFRP.

  According to the present invention, in addition to the sixteenth or seventeenth feature, the distance between the side walls on both sides in the vehicle width direction of the CFRP frame integrally formed on the rear portion of the CFRP vehicle body floor is A vehicle body structure for an automobile is proposed, which has an eighteenth feature of expanding from the rear to the front.

  According to the present invention, in addition to the eighteenth feature, the vertical height of the CFRP frame kicked up from the front to the rear is the vertical height of the floor tunnel portion provided on the vehicle body floor. A vehicle body structure having the nineteenth feature of being substantially the same is proposed.

  According to the present invention, in addition to the nineteenth feature, the distance between the side walls on the both sides in the vehicle width direction of the floor tunnel portion is widened from the front to the rear in the vertical direction as viewed from the front. A vehicle body structure characterized by the above is proposed.

  According to the invention, in addition to any one of the sixteenth to twentieth features, the mount member is made of an aluminum alloy casting, and is fitted to the lower surface of the concave portion of the CFRP frame from below. An upper wall of a U-shaped cross section, a lower wall of a belt shape, a vertical wall connecting the upper wall and the lower wall, and a reinforcing rib connecting the upper wall, the lower wall and the vertical wall A vehicle body structure having the twenty-first feature is proposed.

  According to the invention, in addition to the twenty-first feature, there is proposed a vehicle body structure for an automobile according to the twenty-second feature, wherein the weakened portion is a groove in the vehicle width direction formed in the reinforcing rib.

  According to the invention, in addition to any one of the eighteenth to twentieth characteristics, a side sill extending in the front-rear direction is connected to the upper surface of the vehicle width direction outer end portion of the vehicle body floor, and the vehicle body floor is A vehicle body structure for an automobile according to a twenty-third feature is proposed, comprising a bent portion that bends to cover the rear end of the side sill.

  According to the present invention, in addition to any one of the sixteenth to twenty-third features, a metal fuse member that is plastically deformed when a load greater than a predetermined value is input to the vehicle body above the rear side frame is provided. A vehicle body structure for an automobile is proposed, in which the upper end of the rear damper is supported.

  The side sill 12 of the embodiment corresponds to the vehicle body of the present invention, the rear wheel house inner 23 of the embodiment corresponds to the vehicle body or the rear damper support member of the present invention, and the tunnel side wall 25b of the embodiment is the main body. Corresponding to the side wall of the invention, the fuse member 59 of the embodiment corresponds to the mounting member of the invention, the rear damper 62 of the embodiment corresponds to the rear suspension part of the invention, and the trailing arm 67 of the embodiment. Corresponds to the rear suspension part or suspension arm of the present invention, the bracket 69 of the embodiment corresponds to the mount member of the present invention, and the CFRP frame 74 of the embodiment corresponds to the vehicle body of the present invention. The CFRP frame side wall 74b corresponds to the side wall of the present invention, and the metal frame 75 of the embodiment is the mount of the present invention. Corresponds to wood, the groove 75f of the embodiment corresponds to the weakened portion of the present invention, the damper spring 78 of the embodiment corresponds to the rear suspension part of the present invention.

  According to the first feature of the present invention, when the rear suspension component is supported on the CFRP vehicle body, a metal mount member having a fragile portion is disposed between the vehicle body and the rear suspension component. Since the plastic deformation occurs when an excessive load that does not cause destruction of the vehicle body is input from the rear suspension component to the vehicle body, not only can the destruction of the CFRP vehicle body be prevented, but also the vehicle body and the rear suspension component Can be maintained. Moreover, it is difficult to visually confirm from the outside that the destruction of the CFRP vehicle body is the internal delamination of the CFRP laminate, but the plastic deformation of the mount member can be easily confirmed visually from the outside. A damaged mounting member can be reliably replaced and repaired.

  According to the second feature of the present invention, since the vehicle body is a rear damper support member and the rear suspension part is a rear damper, the rear damper support member is formed by plastically deforming the mount member with a load input from the rear damper. Can be prevented.

  According to the third feature of the present invention, the upper end of the rear damper support member is joined to an extension portion extending rearward of the upper end of the rear pillar, and the mount member is supported on the lower surface of the step portion formed on the rear damper support member. Since the upper surface of the step portion of the rear damper support member and the extension portion are connected via the connecting member, the load input from the mount member to the step portion of the rear damper support member is transmitted to the rear pillar via the connecting member and the extension portion. Can be absorbed.

  According to the fourth aspect of the present invention, the lower part of the CFRP vehicle body stands from the vehicle body floor, the left and right side sills extending in the front-rear direction along the vehicle width direction outer end of the vehicle body floor, and the front ends of the left and right side sills. The left and right front pillar lowers, the dash panel lower connecting the left and right front pillar lowers and joining the front end of the vehicle floor, the left and right rear pillars standing from the rear ends of the left and right side sills, and the left and right rear pillars The rear bulkhead is joined to the rear end of the vehicle floor so that it can be reinforced to surround the vehicle floor to increase the strength of the passenger compartment, and the rear floor extending rearward from the rear end of the vehicle floor. The outer end in the vehicle width direction and the left and right rear pillars including the extension are connected by the left and right rear damper support members, and the rear floor, the rear bulkhead, and the left and right rear dampers are connected. Having partitioned the luggage compartment by the support member, the cargo room in the rear of the vehicle body floor can be easily formed.

  According to the fifth feature of the present invention, since the vehicle body floor is a hollow member made up of an under floor panel and an upper floor panel, the strength of the vehicle body floor can be increased.

  According to the sixth aspect of the present invention, the vehicle body floor includes a protruding portion that protrudes outward in the vehicle width direction from the outer end of the side sill in the vehicle width direction, and at least the energy absorbing member is disposed in the protruding portion. First, the collision load of the vehicle body floor is input to the projecting portion of the vehicle body floor, and a part of the collision energy is absorbed by the crushing of the energy absorbing member, so that the side sill can be prevented from falling inward in the vehicle width direction. Since the outer end in the vehicle width direction and the outer end in the vehicle width direction of the side sill are connected by the connecting member, the side sill can be prevented from falling down more reliably.

  According to the seventh feature of the present invention, the rear partition wall is joined to the upper surface of the rear floor, the inner surface in the vehicle width direction of the rear damper support member, and the lower surface of the rear pillar, so that the rear partition wall ensures the rigidity of the rear part of the vehicle body. It is possible to secure the maximum volume of the passenger compartment.

  According to the eighth aspect of the present invention, the rear partition wall, which is a hollow member made of an outer skin and an inner skin, is integrally formed with a rear par shell extending rearward from the upper end thereof, and is formed in an inverted L-shaped cross section. Since the outer skin and the inner skin are joined to each other at the bent portion at the front end of the rear par shell, it is possible to avoid stress concentration on the outer skin at the bent portion at the front end of the rear par shell while increasing the strength by hollowing the rear partition wall. it can.

  According to the ninth feature of the present invention, the left and right rear side frames are provided on the lower surface of the rear floor, and the rear damper support member connects the rear pillar and the rear side frame, so that the load input from the rear damper to the mount member can be It can be transmitted from the damper support member to the side sill via the rear pillar, and can be transmitted from the rear damper support member to the rear side frame for absorption.

  According to the tenth feature of the present invention, since the vehicle body is a side sill and the rear suspension component is a suspension arm, the mounting member is plastically deformed by a load input from the suspension arm to prevent the side sill from being broken. Can do.

  According to the eleventh feature of the present invention, the side sill extending in the front-rear direction along the vehicle width direction outer end of the CFRP body floor, the front pillar lower standing from the front end of the side sill, and rising from the rear end of the side sill. Since the rear pillar is formed in a U shape in a side view, the strength of the side sill is increased by mutually reinforcing the body floor, the front pillar lower, and the rear pillar, and the support strength of the mount member with respect to the side sill is increased.

  According to the twelfth feature of the present invention, since the vehicle body floor is a hollow member formed by joining the joint flange of the under floor panel and the joint flange of the upper floor panel, the strength of the vehicle body floor can be increased.

  According to the thirteenth feature of the present invention, the mount member is fastened by a bolt that is screwed into a nut embedded in the rear end portion of the side sill, with a joint flange that joins the under floor panel and the upper floor panel interposed therebetween. Therefore, the load input to the mount member can be dispersed and effectively absorbed not only on the side sill but also on the vehicle body floor.

  According to the fourteenth feature of the present invention, since the mount member is cut out from the aluminum extruded material having a constant cross section in the longitudinal direction, the mount member can be easily manufactured. The mount member includes a bottom wall formed with a bolt hole through which the bolt passes, a pair of side walls standing parallel to each other from the bottom wall, and a pair of reinforcing walls that obliquely connect the bottom wall and the pair of side walls. Since the reinforcing wall can be used to increase the rigidity of the mounting member, the suspension arm mounting hole is formed on the distal end side of the side wall, and the fragile portion is formed between the mounting hole and the reinforcing wall. When an excessive load is input, the weak part can be reliably plastically deformed.

  According to the fifteenth feature of the present invention, the vehicle body floor includes a protruding portion that protrudes outward in the vehicle width direction from the outer end of the side sill in the vehicle width direction, the energy absorbing member is disposed at least in the protruding portion, Since the outer end in the vehicle width direction and the outer end in the vehicle width direction of the side sill are connected by a connecting member, the collision load of the side collision is first input to the protruding part of the vehicle body floor, and a part of the collision energy is destroyed by the collapse of the energy absorbing member. By absorbing, the side sill can be prevented from falling inward in the vehicle width direction, and the outer end of the protruding portion in the vehicle width direction and the outer end of the side sill in the vehicle width direction are connected by a connecting member. Can be more reliably prevented.

  According to the sixteenth feature of the present invention, the vehicle body is a CFRP frame of the rear side frame and the rear suspension part is a damper spring. Therefore, the mount member is plastically deformed by a load input from the damper spring, whereby the CFRP frame is obtained. Can be prevented. In addition, the front and top surfaces of the mount member are respectively joined to the front and bottom surfaces of the recess formed in the rear part of the CFRP frame, and the front surface of the mount member and the front surface of the CFRP frame recess are inclined from the front lower side to the rear upper side. Since the member has a fragile part that breaks when a load of a predetermined value or more is input from the damper spring, not only can a part of the rear side frame be made of metal to reduce the weight, but also when an excessive load is input from the damper spring. The load can be absorbed by the fragile portion breaking and plastic deformation of the mount member, and the upward load input to the mount member is efficiently transferred from the inclined front surface of the mount member to the inclined front surface of the CFRP frame recess. Can be transmitted and absorbed.

  According to the seventeenth feature of the present invention, since the CFRP frame is continuous with the CFRP rear floor, the number of parts can be reduced to reduce the weight of the vehicle body, and the strength of the CFRP frame and the rear floor can be reduced. Can be mutually enhanced.

  According to the eighteenth feature of the present invention, the distance between the side walls in the vehicle width direction of the CFRP frame integrally formed on the rear part of the CFRP vehicle body floor is widened from the rear to the front as viewed in the vertical direction. Therefore, the collision load of the rear collision input to the CFRP frame can be uniformly dispersed in the rear part of the vehicle body floor and efficiently absorbed.

  According to the nineteenth feature of the present invention, the vertical height of the CFRP frame kicked up from the front to the rear is substantially the same as the vertical height of the floor tunnel portion provided on the vehicle body floor. The collision load of the rear collision input to the CFRP frame can be efficiently transmitted to the floor tunnel portion and distributed to the vehicle body floor.

  According to the twentieth feature of the present invention, the distance between the side walls of the floor tunnel portion on both sides in the vehicle width direction widens from the front to the rear in the vertical direction, so that the CFRP frame to the floor tunnel portion The load can be transmitted more efficiently.

  According to a twenty-first feature of the present invention, the mount member is made of an aluminum alloy casting, and the upper wall of the U-shaped cross section that fits from below into the lower surface of the recess of the CFRP frame, Since the vertical wall connecting the upper wall and the lower wall and the reinforcing rib connecting the upper wall, the lower wall and the vertical wall are provided, not only the strength of the mount member can be reduced but also the strength can be secured, and the frame made of CFRP In addition, the mount member can be firmly coupled.

  According to the twenty-second feature of the present invention, since the weakened portion is a groove in the vehicle width direction formed in the reinforcing rib, when an excessive load is input from the damper spring while ensuring the strength of the mount member in normal times. The plastic deformation of the mount member can be induced from the groove of the reinforcing rib.

  According to the twenty-third feature of the present invention, the side sill extending in the front-rear direction is connected to the upper surface of the vehicle width direction outer end portion of the vehicle body floor, and the vehicle body floor is bent upward to cover the rear end of the side sill. Therefore, when the collision load of the rear collision is input to the vehicle body floor, the collision load can be transmitted from the bent portion to the rear end of the side sill and efficiently absorbed.

  According to the twenty-fourth feature of the present invention, since the upper end of the rear damper is supported via a metal fuse member that plastically deforms when a load greater than a predetermined value is input to the vehicle body above the rear side frame, the rear damper When an excessive load is input from the fuse member, the fuse member is plastically deformed to absorb the load, thereby preventing the vehicle body above the rear side frame from being broken.

FIG. 1 is a perspective view of a body frame of an automobile as viewed obliquely from the front. (First embodiment) FIG. 2 is a perspective view of the body frame of the automobile as viewed obliquely from the rear. (First embodiment) FIG. 3 is a view in the direction of arrows 3 in FIG. (First embodiment) 4 is a view taken in the direction of arrows 4A and 4B in FIG. (First embodiment) 5 is a cross-sectional view taken along line 5-5 of FIG. (First embodiment) 6 is a view in the direction of arrows 6 in FIG. (First embodiment) 7 is a cross-sectional view taken along line 7-7 of FIG. (First embodiment) 8 is a cross-sectional view taken along line 8-8 in FIG. (First embodiment) FIG. 9 is an explanatory diagram of a method for manufacturing a fuse member. (First embodiment) FIG. 10 is a perspective view of the rear end portion of the left side sill. (Second Embodiment) 11A is a view taken in the direction of arrow 11 in FIG. 10, and FIG. 11B is a cross-sectional view taken along line BB in FIG. 11A. (Second Embodiment) FIG. 12 is a perspective view of the bracket. (Second Embodiment) FIG. 13 corresponds to FIG. (Third embodiment) 14 is a view in the direction of arrow 14 in FIG. (Third embodiment) FIG. 15 is an enlarged view of part 15 of FIG. (Third embodiment)

11 Car body floor 11a Floor tunnel part 11c Projection part 11k Bending part 12 Side sill (vehicle body)
13 Front pillar lower 14 Rear pillar 14a Extension part 17 Dash panel lower 18 Rear partition wall 19 Rear par shell 22 Rear side frame 23 Rear wheel house inner (vehicle body, rear damper support member)
23a Step 25 Under floor panel 25b Tunnel side wall (side wall)
25d Joining flange 26 Upper floor panel 26b Joining flange 30 Energy absorbing member 37 Connecting member 44 Rear floor 45 Loading chamber 59 Fuse member (mounting member)
62 Rear damper (rear suspension parts)
63 Connecting member 64 Inner skin 65 Outer skin 67 Trailing arm (rear suspension part, suspension arm)
69 Bracket (mounting member)
69a Bottom wall 69b Side wall 69c Reinforcement wall 69d Bolt hole 69e Mounting hole 69f Weak part 70 Nut 71 Bolt 74 CFRP frame (vehicle body)
74a Recess 74b CFRP frame side wall (side wall)
75 Metal frame (mounting member)
75a Upper wall 75b Lower wall 75c Vertical wall 75d Reinforcement rib 75f Groove (fragile part)
78 Damper spring (rear suspension parts)

  Hereinafter, embodiments of the present invention will be described with reference to FIGS. In the present specification, the front-rear direction, the left-right direction (vehicle width direction), and the up-down direction are defined with reference to an occupant seated in the driver's seat.

First embodiment

  First, a first embodiment of the present invention will be described with reference to FIGS.

  As shown in FIGS. 1 to 4, an automobile body frame mainly made of CFRP (carbon fiber reinforced resin) includes a body floor 11 and a pair of left and right sides extending in the front-rear direction along the left and right sides of the body floor 11. Side sills 12, 12; a pair of left and right front pillars 13 and 13 standing up front from the front ends of the left and right side sills 12, 12, and a pair of left and right rear pillars rising up from the rear ends of the left and right side sills 12, 12. 14, 14 and a pair of left and right center pillars 15 and 15 rising upward from the middle part in the front-rear direction of the left and right side sills 12 and 12, and the left and right center pillars 15 and 15 from the upper ends of the left and right front pillar lowers 13 and 13. A pair of left and right upper members 16, 16 extending to the upper ends of the left and right rear pillars 14, 14 via the upper ends are provided. The upper ends of the left and right center pillars 15 and 15 are joined by the roof arch 24.

  A flat dash panel lower 17 is joined to the front end of the vehicle body floor 11 and the front surfaces of the left and right front pillar lowers 13, 13, and a flat plate rear portion is connected to the rear end of the vehicle body floor 11 and the rear surfaces of the left and right rear pillars 14, 14. The partition wall 18 is joined, and the rear pershell 19 extends horizontally from the rear end of the rear partition wall 18. A pair of left and right aluminum alloy mounting bases 20, 20 are fixed to the front end of the vehicle body floor 11, and the rear ends of a pair of left and right aluminum alloy front side frames 21, 21 are fixed to the front ends of the mounting bases 20, 20. .

  A pair of left and right rear side frames 22, 22 extend rearward from the rear end of the lower wall of the vehicle body floor 11, and the rear pillars 14, 14 and the rear side frames 22, 22 are joined by a pair of left and right rear wheel house inners 23, 23. . The rear end of the upper wall of the vehicle body floor 11 ends at the position of the rear partition wall 18, and a rear floor 44, which is a member different from the upper wall of the vehicle body floor 11, is disposed behind the rear partition wall 18. Rear side frames 22, 22 having a closed cross section are constituted by the lower wall of the vehicle body floor 11 extending rearward and the rear floor 44. A luggage compartment 45 is defined above the rear floor 44.

  As shown in FIGS. 1, 2, and 5, the vehicle body floor 11 is continuous with the inverted U-shaped floor tunnel portion 11 a extending in the front-rear direction at the center in the vehicle width direction, and on both sides of the floor tunnel portion 11 a in the vehicle width direction. And a pair of left and right floor portions 11b, 11b. The under floor panel 25 includes a tunnel portion upper wall 25a, a pair of left and right tunnel portion side walls 25b and 25b extending downward from the outer end in the vehicle width direction of the tunnel portion upper wall 25a, and a vehicle width from the lower end of the tunnel portion side walls 25b and 25b. Floor portion lower walls 25c, 25c extending outward in the direction, and the floor portion upper walls 26a, 26a of the pair of left and right upper floor panels 26, 26 are formed to be substantially flat along the upper surfaces of the floor portion lower walls 25c, 25c. The

  The floor portion 11b including the floor portion lower wall 25c of the under floor panel 25 and the floor portion upper wall 26a of the upper floor panel 26 is thicker in the vertical direction at both ends in the vehicle width direction than in the center portion in the vehicle width direction. A pair of upper and lower energy absorbing members 30, 30 are disposed in the thickened portion. The energy absorbing members 30 and 30 are made of a corrugated member made of PA (polyamide) or nylon excellent in shock absorbing performance.

  A support wall 31 is fixed to the inner side in the vehicle width direction of the energy absorbing members 30, 30 by adhesion, and the energy absorbing members 30, 30 are fitted into fitting grooves formed on the outer surface of the support wall 31 in the vehicle width direction. Joined by adhesion. The upper surfaces of the energy absorbing members 30 and 30 are bonded to the lower surface of the upper floor panel 26 by bonding, and the lower surfaces of the energy absorbing members 30 and 30 are bonded to the upper surface of the under floor panel 25 by bonding.

  A load distribution frame 32 made of CFRP (or made of aluminum alloy) extending in the front-rear direction is disposed on the inner side of the support wall 31 in the vehicle width direction and the thickness of the floor portion 11b changes. The upper surface and the lower surface of the load distribution frame 32 are bonded to the lower surface of the upper floor panel 26 and the upper surface of the under floor panel 25, respectively, and the outer surface in the vehicle width direction is bonded to the inner surface in the vehicle width direction of the support wall 31. A corrugated core 33 is disposed in the floor portion 11b on the inner side in the vehicle width direction of the load distribution frame 32, and the upper surface and the lower surface thereof are bonded to the lower surface of the upper floor panel 26 and the upper surface of the under floor panel 25, respectively. The

  The side sill 12 includes an outer wall 46, an upper wall 47, a lower wall 48, and an inner wall 49, and is configured in a quadrangular closed cross section, and a plurality of partition plates 36 are arranged at predetermined intervals in the front-rear direction. Is done. The lower wall 48 of the side sill 12 is placed on the upper surface of the upper floor panel 26 and joined by bonding at the outer end in the vehicle width direction of the vehicle body floor 11, that is, at the upper part of the energy absorbing members 30, 30. 11 protrudes outward in the vehicle width direction from the outer end of the side sill 12 in the vehicle width direction. The upper and lower ends of the connecting member 37 having a cross-sectional crank shape made of CFRP plate material are joined to the outer end in the vehicle width direction of the side sill 12 and the outer end in the vehicle width direction of the vehicle body floor 11 by bonding.

  6 to 8, the rear wheel house inner 23 includes a horizontal step portion 23a, and a fuse member 59, which is an aluminum alloy mounting member, is provided on the lower surface of the step portion 23a with a bolt 60 and a nut 61. It is fixed at…. The fuse member 59 is a member having a flat mounting portion 59a, a large-diameter hollow portion 59b, a small-diameter hollow portion 59c, and a flat-plate-shaped damper support portion 59d, and a part of the extruded material having a constant cross section. Can be easily manufactured (see FIG. 9). The upper end of the rear damper 62 of the rear suspension device is supported by the damper support portion 59d.

  The attachment portion 59a and the damper support portion 59d of the fuse member 59 are located on the outer side in the vehicle width direction and are relatively thin on the outer wall 59e and the intermediate wall 59f surrounding the hollow portion 59c, and are located on the inner side in the vehicle width direction. A relatively thick inner wall 59g surrounding a part of the portion 59b is connected in the vertical direction. The thin outer wall 59e and the intermediate wall 59f constitute a fragile portion that collapses when the upward load input from the rear damper 62 exceeds a predetermined value.

  The upper end of the side wall portion 23b that extends upward from the outer end in the vehicle width direction of the step portion 23a of the rear wheel house inner 23 is joined to the lower surface of the extension portion 14a that extends the upper end of the rear pillar 14 rearward. The lower surface of the rear par shell 19 that connects the lower surfaces of 14a and 14a, the inner surface in the vehicle width direction of the side wall portion 23b of the rear wheel house inner 23, and the upper surface of the step portion 23a of the rear wheel house inner 23 are made of CFRP laminates. The two front and rear connecting members 63, 63 are joined. The two front and rear connecting members 63 and 63 are positioned above the fuse member 59.

  The rear partition wall 18 and the rear par shell 19 that are bent in an L-shaped cross section are hollow members having a corrugated core 66 sandwiched between the inner skin 64 and the outer skin 65, but the bent portion at the boundary between the rear partition wall 18 and the rear par shell 19. Thus, the upper surface of the outer skin 65 is in contact with and joined to the lower surface of the inner skin 64 at the portion where the core 66 is interrupted.

  Next, the operation of the first embodiment of the present invention having the above configuration will be described.

  When the collision load of the side collision is input to the vehicle width direction outer ends of the vehicle body floor 11 and the side sill 12, the energy absorbing members 30, 30 disposed inside the vehicle body floor 11 and the partition plates 36 disposed inside the side sill 12. Crushes and absorbs a part of the collision energy, and the collision energy that could not be absorbed there is transmitted to the floor portion 11b of the vehicle body floor 11 via the load distribution frame 32 and absorbed.

  At this time, the vehicle body floor 11 includes a protrusion 11c that protrudes outward in the vehicle width direction from the side sill 12, and the energy absorbing members 30 and 30 are disposed at least in the protrusion 11c (see FIG. 5). By causing the load to be input to the protruding portion 11c of the vehicle body floor 11 before the side sill 12, and absorbing a part of the collision energy by the collapse of the energy absorbing members 30 and 30 disposed in the protruding portion 11c of the vehicle body floor 11, The side sill 12 can be prevented from falling inward in the vehicle width direction.

  In addition, the vehicle body floor 11 on the inner side in the vehicle width direction than the side sill 12 is configured by sandwiching a core 33 between an under floor panel 25 made of CFRP laminate and an upper floor panel 26 made of CFRP laminate, and the vehicle floor 11 has energy. The thickness of the portion that houses the absorbing members 30 and 30 is larger than the thickness of the portion that houses the core 33, and the load distribution frame 32 is provided between the energy absorbing members 30 and 30 and the core 33 (see FIG. 5). The thickness of the vehicle body floor 11 on the inner side in the vehicle width direction is decreased while increasing the thickness of the energy absorbing members 30 and 30 to increase the energy absorption performance against the collision load of the side collision input to the side sill 12. Weight reduction can be achieved.

  Now, the load accompanying the vertical movement of the rear wheel is transmitted to the step portion 23a of the rear wheel house inner 23 via the rear damper 62 of the rear suspension device, but between the rear damper 62 and the step portion 23a of the rear wheel house inner 23. A fuse member 59 made of an aluminum alloy is disposed between the fuse member 59, and the fuse member 59 includes hollow portions 59b and 59c between the attachment portion 59a and the damper support portion 59d. Therefore, the rear wheel house inner 23 can be destroyed from the rear damper 62. When an excessive load that does not reach is input, the thin outer wall 59e and the intermediate wall 59f of the fuse member 59 are plastically deformed so as to be bent or curved outward in the vehicle width direction due to metal ductility, and the fuse member 59 is moved in the vertical direction. CFRP rear wheel house by crushing like a crush (see Fig. 8) Not only can the inner 23, the extension 14a of the rear pillar 14 connected thereto, and the rear par shell 19 be prevented from being destroyed, but also the connected state of the rear damper 62 and the rear wheel house inner 23 is maintained even if the fuse member 59 is crushed. can do.

  Moreover, when the fracture of the CFRP rear wheel house inner 23 is the internal delamination of the CFRP laminate, it is difficult to visually confirm the fracture from the outside, but the plastic deformation of the metal fuse member 59 is difficult. Can be easily visually confirmed from the outside, so that the damaged fuse member 59 can be reliably replaced and repaired. The fuse member 59 is plastically deformed when an excessive load is input from the rear damper 62 due to a collision accident or the like, and has sufficient rigidity with respect to the load input during normal travel. The outer wall 59e and the intermediate wall 59f of the member 59 are not plastically deformed.

  Further, the upper end of the side wall portion 23b of the rear wheel house inner 23 is joined to an extension portion 14a obtained by extending the upper end of the rear pillar 14 rearward, and a fuse member 59 is supported on the lower surface of the step portion 23a of the rear wheel house inner 23. Since the upper surface of the step portion 23a of the house inner 23 and the extension portion 14a are connected via connecting members 63 and 63 (see FIG. 6), the load input from the fuse member 59 to the step portion 23a of the rear wheel house inner 23 is applied. It can be transmitted to the rear pillar 14 via the connecting members 63 and 63 and the extension portion 14a and absorbed.

  Further, left and right rear side frames 22 and 22 are provided on the lower surface of the rear floor 44, and the rear wheel house inners 23 and 23 connect the rear pillars 14 and 14 and the rear side frames 22 and 22 (see FIG. 6). The load input to the fuse members 59, 59 is transmitted from the rear wheel house inners 23, 23 to the side sills 12, 12 via the rear pillars 14, 14, and from the rear wheel house inners 23, 23 to the rear side frames 22, 22. Can be transmitted and absorbed.

  The vehicle body floor 11 includes left and right side sills 12, 12, left and right front pillar lowers 13, 13 rising from front ends of the left and right side sills 12, 12, and a dash panel lower 17 that connects the left and right front pillar lowers 13, 13. The left and right rear pillars 14, 14 rising from the rear ends of the left and right side sills 12, 12 and the rear partition wall 18 connecting the left and right rear pillars 14, 14 are provided, so that they are reinforced to surround the vehicle body floor 11. Not only can the strength of the passenger compartment be increased, but also the outer ends in the vehicle width direction of the rear floor 44 extending rearward from the rear end of the vehicle body floor 11 and the left and right rear pillars 14 and 14 including the extension portions 14a and 14a Of the rear wheel house inner 23, 23, the rear floor 44, the rear partition 18 and the left and right rear wheel house ins. Having partitioned the luggage compartment 45 in over 23, the cargo room 45 in the rear of the vehicle body floor 11 can be easily formed.

  Moreover, the rear partition 18 is joined to the upper surface of the rear floor 44, the inner surfaces in the vehicle width direction of the rear wheel house inners 23, 23, and the lower surfaces of the rear pillars 14, 14, so that the rear partition 18 can secure the rigidity of the rear part of the vehicle body. The maximum volume can be secured.

  The rear partition 18, which is a hollow member composed of the inner skin 64 and the outer skin 65, is integrally formed with a rear par shell 19 that extends rearward from the upper end of the rear partition 18, and is formed in an inverted L-shaped cross section. Since the inner skin 64 and the outer skin 65 are joined to each other in this manner, it is possible to avoid stress concentration on the outer skin 65 at the bent portion at the front end of the rear pershell 19 while increasing the strength by making the rear partition wall 18 hollow. .

Second embodiment

  Next, a second embodiment of the present invention will be described with reference to FIGS.

  As shown in FIGS. 10 to 12, a metal bracket 69 that is a mounting member for supporting the rubber bush joint 68 at the front end of the trailing arm 67 of the rear suspension device is fixed to the rear end portion of the side sill 12. The The bracket 69 is cut from an extruded material made of an aluminum alloy having a constant cross section in the longitudinal direction (see FIG. 12), and connects the pair of rectangular bottom walls 69a and 69a and the pair of bottom walls 69a and 69a. A pair of substantially V-shaped side walls 69b and 69b extending in parallel with each other, and the bottom walls 69a and 69a and the side walls 69b and 69b are obliquely connected by reinforcing walls 69c constituting a truss. Two bolt holes 69d and 69d are formed in the bottom wall 69a, and mounting holes 69e and 69e of the rubber bush joint 68 of the trailing arm 67 are formed at the apex portions of the substantially V-shaped side walls 69b and 69b. An intermediate portion of the side walls 69b and 69b sandwiched between the bottom walls 69a and 69a and the bolt holes 69d and 69d constitutes a fragile portion 69f that can be plastically deformed by a load.

  The under floor panel 25 and the upper floor panel 26 constituting the vehicle body floor 11 are configured to have a hollow cross section by joining the joining flanges 25d and 26b formed on the outer peripheral portions thereof to overlap each other (see FIG. 5). ). The rear ends of the joint flanges 25d, 26b at the outer end in the vehicle width direction of the vehicle body floor 11 are formed wide in the vertical direction, and are bent inward in the vehicle width direction so as to overlap the rear end of the side sill 12. The bottom wall 69a on the lower side of the bracket 69 is fixed so as to face rearward.

  That is, two nuts 70, 70 are embedded in the rear end portion of the side sill 12, the bolt holes 69 d, 69 d of the bottom wall 69 a on the lower side of the bracket 69, the joint flanges 25 d, 26 b of the vehicle body floor 11, and the side sill 12. By screwing two bolts 71, 71 penetrating through the rear end portion into two nuts 70, 70, the bottom wall 69a on the lower side of the bracket 69 sandwiches the joining flanges 25d, 26b, and the side sill 12 is fixed to the rear end. Similarly, the bottom wall 69a on the upper side of the bracket 69 is fixed to the upper part of the rear end portion of the side sill 12 with respect to the joining flanges 25d and 26b by two bolts 71 and 71 in the same manner. The rubber bush joint 68 of the trailing arm 67 is supported by the bracket 69 with bolts 73 that pass through the bushes 72 and 72 fitted into the mounting holes 69e and 69e formed at the apex portions of the pair of side walls 69b and 69b.

  Next, the operation of the second embodiment of the present invention having the above configuration will be described.

  When an excessive load in the front-rear direction is input from the trailing arm 67 of the rear suspension device to the bracket 69 via the rubber bush joint 68 when traveling on an uneven road surface, a pair of side walls 69b of the aluminum alloy bracket 69, The fragile portions 69f of 69b are plastically deformed so as to be crushed in the front-rear direction (see the chain line in FIG. 11B), thereby preventing the side sill 12 to which the bracket 69 is attached from being broken. Moreover, it is sufficient to use only the bracket 69 as a metal member without applying special reinforcement to the side sill 12 using a metal member, so that an increase in weight can be minimized.

  Particularly, since the bracket 69 is cut out from an extruded material made of an aluminum alloy having a constant cross section in the longitudinal direction, the bracket 69 can be easily manufactured. The bracket 69 has a pair of bottom walls 69a, 69a formed with bolt holes 69d through which the bolts 71 pass, and a pair of substantially V-shaped side walls standing in parallel with each other from the pair of bottom walls 69a, 69a. 69b, 69b and the pair of bottom walls 69a, 69a and the pair of side walls 69b, 69b are provided with the reinforcement walls 69c, which are obliquely connected, so that the rigidity of the bracket 69 can be increased by the reinforcement walls 69c.

  In addition, mounting holes 69e and 69e of the trailing arm 67 are formed at the apex portions of the side walls 69b and 69b, and the load input direction from the trailing arm 67 between the mounting holes 69e and 69e and the reinforcing wall 69c. Since the inclined weak portion 69f is formed, when an excessive load is input from the trailing arm 67, the weak portion 69f is reliably plastically deformed in the front-rear direction by metal ductility, and the bracket 69 exhibits a fuse function. Load transmission to the side sill 12 made of CFRP can be cut off. Moreover, since the bracket 69 is only plastically deformed and does not break when a large load is input, the connected state of the trailing arm 67 and the side sill 12 can be maintained.

  In addition, when the destruction of the CFRP side sill 12 is the internal delamination of the CFRP laminate, it is difficult to visually confirm the destruction from the outside, but the plastic deformation of the metal bracket 69 is visually observed from the outside. Thus, the damaged bracket 69 can be reliably replaced and repaired. The bracket 69 is plastically deformed when an excessive load is input from the trailing arm 67 due to a collision accident or the like, and has sufficient rigidity with respect to the load input during normal traveling. The 69 weak portions 69f are not plastically deformed.

  Further, side sills 12, 12 extending in the front-rear direction along the vehicle width direction outer end of the vehicle body floor 11 made of CFRP, front pillar lowers 13, 13 rising from the front ends of the side sills 12, 12, and rear ends of the side sills 12, 12 Since the rear pillars 14 and 14 rising from the side are formed in a U shape in a side view, the strength of the side sills 12 and 12 is enhanced by mutually reinforcing the vehicle body floor 11, the front pillar lowers 13 and 13 and the rear pillars 14 and 14. The support strength of the brackets 69 and 69 with respect to the side sills 12 and 12 can be increased. At that time, the vehicle body floor 11 is a hollow member formed by joining the under-floor panel 25 and the joint flanges 25d and 26b of the upper floor panels 26 and 26, so that the strength can be increased, and the side sill 12 joined to the vehicle body floor 11 The strength of 12 is also increased.

  The lower part of the bracket 69 has bolts 71 that are screwed into nuts 70 and 70 embedded in the rear end portion of the side sill 12 with joint flanges 25d and 26b joining the under floor panel 25 and the upper floor panels 26 and 26 interposed therebetween. Since it is fastened by 71, the load input to the bracket 69 can be dispersed and effectively absorbed not only in the side sill 12 but also in the vehicle body floor 11.

Third embodiment

  Next, a third embodiment of the present invention will be described with reference to FIGS.

  As shown in FIGS. 13 and 14, the rear floor 44 continuing to the rear of the vehicle body floor 11 has a hollow structure including the under floor panel 25 and the upper floor panel 26, as with the vehicle body floor 11. The rear side frame 22 includes a front CFRP frame 74 and a rear metal frame 75, and the CFRP frame 74 is a portion where the rear portion of the vehicle body floor 11 kicks up toward the rear floor 44, and the under floor panel 25. A part of this is bulged downward, and the upper surface thereof is covered with an upper floor panel 26 to form a hollow closed section. On the other hand, a metal frame 75 made of an aluminum alloy casting is joined to the under floor panel 25 constituting the lower surface of the rear half of the rear floor 44 and connected in series behind the CFRP frame 74.

  The rear suspension device that supports the rear wheels includes a trailing arm 67 pivotally supported at the rear end of the side sill 12, a front lower arm 79 pivotally supported at the inner bottom in the vehicle width direction on the front lower surface of the metal frame 75. The rear lower arm 81 pivotally supported at the inner end in the vehicle width direction on the lower surface of the trapezoidal cross member 80 connecting the left and right metal frames 75 and 75, and the intermediate portion in the vehicle width direction of the rear lower arm 81 as the metal frame 75, a damper spring 78 connected to the lower rear surface of the rear part 75, a rear damper 62 connecting the intermediate part in the vehicle width direction of the rear lower arm 81 to the fuse member 59, and a stabilizer 82 connecting the left and right rear lower arms 81, 81 in the vehicle width direction. A trailing arm 67, a front lower arm 79, and a knuckle 83 supported by the rear lower arm 81. A metal joint 84 provided at the outer end in the vehicle width direction of the cross member 80 abuts on the inner surface in the vehicle width direction of the metal frame 75 and is fastened by two bolts 85, 85 penetrating the metal frame 75.

  As shown in FIGS. 14 and 15, the metal frame 75 includes an upper wall 75a having a U-shaped cross section that opens upward, a lower wall 75b having a strip shape, and a vertical wall 75c that connects the upper wall 75a and the lower wall 75b. And a reinforcing rib 75d connecting the upper wall 75a, the lower wall 75b, and the vertical wall 75c, and a front lower arm 79 is pivotally supported on the front portion of the lower wall 75b via a bracket 77, A damper spring support portion 75e that supports the upper end of the damper spring 78 is provided at the rear portion of the lower wall 75b. And the groove | channel 75f as a weak part extended in a vehicle width direction is formed in the reinforcement rib 75d located directly on the damper spring support part 75e.

  The CFRP frame 74 has an L-shaped recess 74a on the lower surface of the rear floor 44, and a metal frame 75 is fitted into the recess 74a and joined by adhesion. At this time, the upper wall 75a of the U-shaped cross section that opens upward fits into the recess 74a of the CFRP frame 74 from below, so that the metal frame 75 is firmly bonded to the CFRP frame 74. The front surface of the metal frame 75 and the front surface of the concave portion 74a of the CFRP frame 74 which are bonded to each other are inclined at an angle θ from the front lower side to the rear upper side (see FIG. 14).

  As shown in FIG. 13, the joint floors 25 d and 26 b of the under floor panel 25 of the vehicle body floor 11 and the upper floor panel 26 are increased in height in the vertical direction at the rear end of the side sill 12, and are turned inward in the vehicle width direction. The bent portion 11k is bent upward and covers the rear end of the side sill 12 from the rear.

  As shown in FIG. 4 (B), the width W1 of the rear part of the left and right tunnel part side walls 25b, 25b of the floor tunnel part 11a of the vehicle body floor 11 widens outward from the front side toward the rear side in the vehicle width direction. doing. Further, the width W2 at the front part of the left and right CFRP frame side walls 74b and 74b of the left and right CFRP frame 74 sandwiching the expanded portion of the floor tunnel portion 11a from both sides in the vehicle width direction is the vehicle width direction from the rear side toward the front side. It spreads outward to the outside.

  As shown in FIG. 14, the vertical height H of the floor tunnel portion 11a substantially coincides with the vertical height H of the CFRP frame 74 located behind the floor tunnel portion 11a, and the floor tunnel portion 11a and the CFRP product. The positions of the frames 74 overlap each other when viewed in the front-rear direction.

  Next, the operation of the third embodiment of the present invention having the above configuration will be described.

  The rear side frame 22 is made of a metal frame 75 to which a large load is input from the trailing arm 67, the front lower arm 79, the rear lower arm 81, the rear damper 62, the damper spring 78, etc. of the rear suspension device, and the other CFRP frame 74. As a result, the weight can be reduced compared with the case where the entire rear side frame 22 is made of metal, and both strength and weight reduction can be achieved.

  When a load of a predetermined value or more is input to the damper spring support portion 75e of the lower wall 75b of the metal frame 75 from the damper spring 78 or the like of the rear suspension device along with the vertical movement of the rear wheel, the upper side of the damper spring support portion 75e The metal frame 75 is plastically deformed from the groove 75f, which is a fragile portion formed in the reinforcing rib 75d (see the upper right circle in FIG. 14), thereby destroying the CFRP frame 74 and the rear floor 44 that support the metal frame 75. Can be prevented. Since the front surface of the metal frame 75 and the front surface of the recess 74a of the CFRP frame 74 are inclined at an angle θ from the front lower side to the rear upper side, the load input to the metal frame 75 from the rear suspension device is applied to the inclined surface. To the CFRP frame 74, and can be efficiently absorbed.

  Further, the metal frame 75 as the mounting member is made of an aluminum alloy casting, and has an upper wall 75a having a U-shaped cross section that fits from below into the lower surface of the concave portion 74a of the CFRP frame 74, a belt-like lower wall 75b, Since the vertical wall 75c that connects the upper wall 75a and the lower wall 75b and the reinforcing ribs 75d that connect the upper wall 75a, the lower wall 75b, and the vertical wall 75c are provided, the metal frame 75 is reduced in weight while ensuring strength. In addition, the CFRP frame 74 and the metal frame 75 can be firmly bonded.

  Further, since the fragile portion of the metal frame 75 is constituted by the groove 75f in the vehicle width direction formed in the reinforcing rib 75d, when an excessive load is input from the damper spring 78 while ensuring the strength of the metal frame 75 in a normal state. Plastic deformation of the metal frame 75 can be induced from the groove 75f of the reinforcing rib 75d. In addition, the weak part of the metal frame 75 is not limited to the groove 75f in the vehicle width direction formed in the reinforcing rib 75d, but by thinning the vertical wall 75c or the reinforcing rib 75d, changing their arrangement, shape, number, etc. Can also be configured.

  As described above, when an excessive load is input from the damper spring 78, it is only possible to prevent the CFRP frame 74 from being broken by plastic deformation due to the metal ductility of the metal frame 75 which is the mounting member of the damper spring 78. The connection relationship between the CFRP frame 74 and the damper spring 78 can be maintained.

  Further, when the CFRP frame 74 breaks due to the internal delamination of the CFRP laminate, it is difficult to visually confirm the break from the outside, but the plastic deformation of the metal frame 75 is easy from the outside. Therefore, the damaged metal frame 75 can be reliably replaced and repaired. The metal frame 75 is plastically deformed when an excessive load is input from the damper spring 78 or the like due to a collision accident or the like, and has sufficient rigidity with respect to the load input during normal traveling. The weak part of the metal frame 75 is not plastically deformed.

  Also, the collision load of the rear collision is transmitted from the metal frame 75 of the rear side frame 22 to the CFRP frame 74. Since the CFRP frame 74 is integrally formed with the rear floor 44 and the vehicle body floor 11, the number of parts is reduced. While reducing the weight of the vehicle body, the strength of the rear floor 44 including the CFRP frame 74 and the vehicle body floor 11 can be increased.

  Moreover, the distance W2 between the left and right CFRP frame side walls 74b, 74b of the CFRP frame 74 formed integrally with the rear portion of the CFRP vehicle body floor 11 widens from the rear to the front as viewed in the vertical direction. (Refer to FIG. 4 (B)), not only can the collision load of the rear collision input to the CFRP frame 74 be uniformly distributed to the rear part of the vehicle body floor 11 and efficiently absorbed, The interval W1 between the tunnel side walls 25b and 25b widens from the front to the rear in the vertical direction (see FIG. 4B), so that the load transmission from the CFRP frame 74 to the floor tunnel portion 11a is performed. It can be performed more efficiently.

  Furthermore, the vertical height H of the CFRP frame 74 kicked up from the front to the rear is substantially the same as the vertical height H of the floor tunnel portion 11a provided on the vehicle body floor 11 (see FIG. 14). The collision load of the rear collision input to the CFRP frame 74 can be efficiently transmitted to the floor tunnel portion 11a and distributed to the vehicle body floor 11.

  Further, a side sill 12 extending in the front-rear direction is connected to the upper surface of the vehicle width direction outer end portion of the vehicle body floor 11, and the vehicle body floor 11 includes a bent portion 11k that is bent upward and covers the rear end of the side sill 12 (see FIG. 13), when the collision load of the rear collision is input to the vehicle body floor 11, the collision load can be transmitted from the bent portion 11k to the rear end of the side sill 12 and efficiently absorbed.

  The embodiments of the present invention have been described above, but various design changes can be made without departing from the scope of the present invention.

  For example, the mount member of the present invention is not limited to the fuse member 59, the bracket 69, and the metal frame 75 of the embodiment.

  Further, the rear suspension component of the present invention is not limited to the rear damper 62, the trailing arm 67 and the damper spring 78 of the embodiment.

  The vehicle body of the present invention is not limited to the rear wheel house inner 23, the side sill 12, and the CFRP frame 74 of the embodiment.

Claims (24)

A vehicle body structure for an automobile that supports rear suspension parts (62, 67, 78) on a CFRP vehicle body (23, 12, 74),
A metal mount member (59, 69, 75) having a fragile portion is disposed between the vehicle body (23, 12, 74) and the rear suspension part (62, 67, 78), and the mount member (59 , 69, 75) when an excessive load is input from the rear suspension part (62, 67, 78) to the vehicle body (23, 12, 74) that does not cause the vehicle body (23, 12) to break. A vehicle body structure characterized by plastic deformation.   The vehicle body structure according to claim 1, wherein the vehicle body (23) is a rear damper support member (23), and the rear suspension component (62) is a rear damper (62).   The upper end of the rear damper support member (23) is joined to an extension (14a) that extends rearward from the upper end of the rear pillar (14), and is attached to the lower surface of the step portion (23a) formed on the rear damper support member (23). The mount member (59) is supported, and the upper surface of the step portion (23a) of the rear damper support member (23) and the extension portion (14a) are connected via a connecting member (63). The vehicle body structure according to claim 2. The lower part of the CFRP vehicle body includes a vehicle body floor (11), left and right side sills (12) extending in the front-rear direction along the vehicle width direction outer end of the vehicle body floor (11), and front ends of the left and right side sills (12). The left and right front pillar lowers (13), the dash panel lower (17) joined to the front end of the vehicle body floor (11) by connecting the left and right front pillar lowers (13), and the left and right side sills ( 12) a left and right rear pillar (14) that stands up from the rear end; and a rear partition wall (18) that connects the left and right rear pillars (14) and joins the rear end of the vehicle body floor (11);
The left and right rear dampers support the outer end in the vehicle width direction of the rear floor (44) extending rearward from the rear end of the vehicle body floor (11) and the left and right rear pillars (14) including the extension (14a). The vehicle (45) is defined by the rear floor (44), the rear partition wall (18), and the left and right rear damper support members (23) connected by a member (23). The vehicle body structure described in 1.   The vehicle body structure according to claim 4, wherein the vehicle body floor (11) is a hollow member comprising an under floor panel (25) and an upper floor panel (26).   The vehicle body floor (11) includes a protruding portion (11c) that protrudes outward in the vehicle width direction from the outer end in the vehicle width direction of the side sill (12), and at least the energy absorbing member (30) in the protruding portion (11c). The vehicle width direction outer end of the protrusion (11c) and the vehicle width direction outer end of the side sill (12) are connected by a connecting member (37). 5. A vehicle body structure according to 5.   The said rear partition (18) is joined to the upper surface of the said rear floor (44), the vehicle width direction inner surface of the said rear damper support member (23), and the lower surface of the said rear pillar (14). The vehicle body structure of the automobile according to any one of claims 6 to 7.   The rear partition wall (18), which is a hollow member made of an outer skin (65) and an inner skin (64), is integrally formed with a rear pershell (19) extending rearward from the upper end thereof, and is formed in an inverted L-shaped cross section. The outer skin (65) and the inner skin (64) are joined to each other at a bent portion at a front end of the rear par shell (19). Car body structure.   The left and right rear side frames (22) are provided on the lower surface of the rear floor (44), and the rear damper support member (23) connects the rear pillar (14) and the rear side frame (22). The vehicle body structure according to any one of claims 4 to 8.   The vehicle body structure according to claim 1, wherein the vehicle body (12) is a side sill (12) and the rear suspension component (67) is a suspension arm (67).   The side sill (12) extending in the front-rear direction along the vehicle width direction outer end of the vehicle body floor (11) made of CFRP, the front pillar lower (13) rising from the front end of the side sill (12), and the side sill (12 11. The vehicle body structure according to claim 10, wherein the rear pillar (14) rising from the rear end is formed in a U shape in a side view.   The said vehicle body floor (11) is a hollow member which joined the joining flange (25d) of an under floor panel (25), and the joining flange (26b) of an upper floor panel (26), It is characterized by the above-mentioned. Vehicle body structure described.   The mount member (69) is a nut embedded in a rear end portion of the side sill (12) with a joint flange (25d, 26b) joining the under floor panel (25) and the upper floor panel (26) interposed therebetween. The vehicle body structure according to claim 12, wherein the vehicle body structure is fastened by a bolt (71) screwed to (70).   The mount member (69) is cut from an extruded material made of an aluminum alloy having a constant cross section in the longitudinal direction, and a bottom wall (69a) in which a bolt hole (69d) through which the bolt (71) passes is formed, and the bottom A pair of side walls (69b) that stand parallel to each other from the wall (69a), and a pair of reinforcing walls (69c) that obliquely connect the bottom wall (69a) and the pair of side walls (69b), The attachment hole (69e) of the suspension arm (67) is formed on the distal end side of the side wall (69b), and the fragile portion (69f) is formed between the attachment hole (69e) and the reinforcing wall (69c). The vehicle body structure according to claim 13, wherein:   The vehicle body floor (11) includes a protruding portion (11c) that protrudes outward in the vehicle width direction from the outer end in the vehicle width direction of the side sill (12), and at least the energy absorbing member (30) in the protruding portion (11c). The vehicle width direction outer end of the protrusion (11c) and the vehicle width direction outer end of the side sill (12) are connected by a connecting member (37). 14. The vehicle body structure according to any one of 14 above.   The vehicle body (74) is a CFRP frame (74) of a rear side frame (22), the rear suspension part (78) is a damper spring (78), and the front surface and upper surface of the mount member (75) are The front surface and the lower surface of the recess (74a) formed in the rear portion of the CFRP frame (74) are respectively joined, and the front surface of the mount member (75) and the front surface of the recess (74a) of the CFRP frame (74) are the front. 2. The mounting member according to claim 1, wherein the mount member is provided with the fragile portion that is plastically deformed when a load of a predetermined value or more is input from the damper spring. The vehicle body structure described in 1.   17. The vehicle body structure according to claim 16, wherein the CFRP frame (74) is integrally connected to a CFRP rear floor (44).   The distance between the side walls (74b) on both sides in the vehicle width direction of the CFRP frame (74) formed integrally with the rear portion of the CFRP vehicle body floor (11) is widened from the rear to the front in the vertical direction. The vehicle body structure according to claim 16 or 17, wherein the vehicle body structure is opened.   The vertical height of the CFRP frame (74) kicked up from the front to the rear is substantially the same as the vertical height of the floor tunnel portion (11a) provided on the vehicle body floor (11). The vehicle body structure according to claim 18.   The distance between the side walls (25b) on both sides in the vehicle width direction of the floor tunnel portion (11a) widens from the front to the rear as viewed in the vertical direction, and widens toward the rear. Body structure.   The mount member (75) is made of an aluminum alloy casting, and has an upper wall (75a) having a U-shaped cross section that fits from below into the lower surface of the recess (74a) of the CFRP frame (74), and a strip shape. A lower wall (75b), a vertical wall (75c) connecting the upper wall (75a) and the lower wall (75b), the upper wall (75a), the lower wall (75b), and the vertical wall (75c). 21. A vehicle body structure according to any one of claims 16 to 20, further comprising a reinforcing rib (75d) for connecting the same).   The vehicle body structure according to claim 21, wherein the weakened portion (75f) is a groove in a vehicle width direction formed in the reinforcing rib (75d).   A side sill (12) extending in the front-rear direction is connected to the upper surface of the vehicle width direction outer end of the vehicle body floor (11), and the vehicle body floor (11) is bent upward to cover the rear end of the side sill (12). The vehicle body structure according to any one of claims 18 to 20, further comprising a bent portion (11k).   The upper end of the rear damper (62) is supported by a vehicle body above the rear side frame (22) via a metal fuse member (59) that is plastically deformed when a load of a predetermined value or more is input. 24. A vehicle body structure according to any one of claims 16 to 23.

Images