JP5781030B2 - Auto body front structure - Google Patents

Description

  The present invention relates to a vehicle body front structure having an FRP bumper beam extension disposed between a front side frame and a bumper beam.

  A pair of left and right deformed protrusions (bumper beam extension) are projected rearward from the rear surface of the bending support body (bumper beam) made of FRP, and these deformation protrusions are formed at the front end of the vertical support body (front side frame). Japanese Patent Application Laid-Open Publication No. 2004-151867 discloses a method in which a deformation projection is crushed by a collision load of a frontal collision to absorb collision energy.

  In addition, a crushing member (bumper beam extension) that extends in the front-rear direction and connects the protective wall at the front of the passenger compartment and the bumper beam is joined to a pair of left and right FRP plates made of glass fiber and carbon fiber laminated in two layers. Japanese Patent Application Laid-Open No. 2004-151867 discloses a structure in which a closed rectangular tube-shaped closed section is formed and a collapsing member is crushed by a collision load of frontal collision to absorb collision energy.

Japanese Patent No. 2827105 US Pat. No. 6,406,088

  However, in the above-described Patent Document 1, the bumper beam and the bumper beam extension are integrally formed by joining the upper and lower members, and the wall surface of the bumper beam and the wall surface of the bumper beam extension are continuously formed. Since they are connected, it is difficult to induce crushing from the front end of the bumper beam extension when a collision load is input from the bumper beam, and the amount of collision energy absorbed may be insufficient.

  In addition, since the bumper beam extension has a rectangular cross section surrounded by a flat surface, the one described in Patent Document 2 may cause out-of-plane deformation of the flat surface, which may make stable crushing difficult. In addition, since the flanges of the pair of left and right plate members are bonded to form a closed cross section, the bonded portion may be easily peeled off and stable crushing may be difficult.

  The present invention has been made in view of the above circumstances, and an object of the present invention is to reliably crush the bumper beam extension when a collision load of a frontal collision is input and to enhance the collision energy absorption effect.

In order to achieve the above object, according to the first aspect of the present invention, a bumper beam extension made of FRP is provided between a front side frame and a bumper beam, and the bumper beam extension is a continuous fiber. An upper member and a lower member in which FRP and discontinuous fiber FRP are laminated are combined to form a closed cross-sectional portion extending in the front-rear direction, and a front fastening flange and a rear fastening flange of discontinuous fiber FRP are formed at the front and rear ends of the bumper beam extension A vehicle body front structure is proposed in which the front fastening flange and the rear fastening flange are connected by a reinforcing rib extending in the front-rear direction .

  According to the invention described in claim 2, in addition to the structure of claim 1, the pin formed on one of the upper member and the lower member is fitted in the pin hole formed on the other, A vehicle body front structure is proposed in which the tip of the pin is melted to join the upper member and the lower member.

  According to a third aspect of the present invention, in addition to the configuration of the first or second aspect, the bumper beam extension has a cross-sectional area outside the closed cross-sectional portion outside the closed cross-sectional portion in the vehicle width direction. There is proposed a vehicle body front structure characterized in that it has at least one sub-closed cross-section with a small height.

According to the invention described in claim 4, in addition to the structure of any one of claims 1 to 3 , the reinforcing rib is formed by the discontinuous fiber FRP on the inner peripheral surface of the closed cross-section portion. A vehicle body front structure characterized by this is proposed.

  According to the invention described in claim 5, in addition to the configuration of claim 4, the front fastening flange is inclined forward and downward from the joint portion of the upper member and the lower member, respectively. A vehicle body front structure characterized by extending is proposed.

  According to the invention described in claim 6, in addition to the configuration of claim 4 or claim 5, a vehicle body front structure of an automobile characterized in that a nut is inserted into the front fastening flange. The

  According to the invention described in claim 7, in addition to the configuration of any one of claims 4 to 6, a temporary fixing protrusion is formed on the front bulkhead, and the temporary fastening flange is provided with the temporary fixing flange. There is proposed a front body structure of an automobile characterized in that a temporary fixing hole that can be engaged with a fixing protrusion is formed.

  According to the invention described in claim 8, in addition to the configuration of any one of claims 4 to 7, the outer end in the vehicle width direction of the mounting plate fixed to the front end of the front side frame, and the A vehicle body front structure is proposed in which the outer side surface of the front side frame is connected with a bracing member and a rear fastening flange of the bumper beam extension is coupled to the mounting plate.

  According to the ninth aspect of the present invention, in addition to the configuration of the third aspect, the cross-sectional areas of the closed cross section and the sub closed cross section are gradually increased from the inner side to the outer side in the vehicle width direction. A vehicle body front structure characterized by being smaller is proposed.

  The front side frame front portion 14 of the embodiment corresponds to the front side frame of the present invention, and the first sub closed cross section 18b and the second sub closed cross section 18c of the embodiment are sub closed cross sections of the present invention. The first reinforcing ribs 51h and 52h and the second reinforcing ribs 51i and 52i of the embodiment correspond to the reinforcing ribs of the present invention.

According to the configuration of the first aspect, the bumper beam extension made of FRP disposed between the front side frame and the bumper beam is formed by joining the upper member and the lower member in which the continuous fiber FRP and the discontinuous fiber FRP are laminated. Reinforcement that forms a closed cross section extending in the front-rear direction, and forms front and rear fastening flanges of discontinuous fiber FRP at the front and rear ends of the bumper beam extension, respectively, and extends the front fastening flange and the rear fastening flange in the front-rear direction Since it is connected with ribs, the strength and formability of the bumper beam extension can be compatible with the continuous fiber FRP and discontinuous fiber FRP , and the bumper beam extension can be firmly coupled to the bumper beam and the front side frame. Against load It is possible to increase the energy absorption amount by suppressing the out-of-plane deformation of the closed cross section of the emissions per beam extension.

  According to the second aspect of the present invention, with the pin formed on one of the upper member and the lower member fitted in the pin hole formed on the other, the tip of the pin is melted to join the upper member and the lower member. Therefore, not only can the upper and lower members be joined together with high accuracy without loosening, but also the coupling strength is increased to prevent the upper and lower members from separating at the time of a frontal collision, and from the front end of the bumper beam extension. The amount of energy absorption can be secured by stabilizing the crushing toward the edge.

  According to the third aspect of the present invention, the bumper beam extension has at least one sub-closed cross-sectional portion having a smaller cross-sectional area than the closed cross-sectional portion outside the closed cross-sectional portion located at the front end of the front side frame in the vehicle width direction. As a result, it is possible not only to absorb the shock at the sub-closed cross section at the time of the narrow offset frontal collision, but also to secure the energy absorption amount while shortening the longitudinal dimension of the bumper beam extension.

According to the fourth aspect of the present invention, since the reinforcing rib is formed by the discontinuous fiber FRP on the inner peripheral surface of the closed cross section, when the collision load of the frontal collision is input from the bumper beam to the bumper beam extension, the closed cross section is formed. Energy absorption performance can be improved by reliably crushing while suppressing out-of-plane deformation of the part.

  According to the fifth aspect of the invention, the front fastening flange of the bumper beam extension extends from the joint portion of the upper member and the lower member so as to incline forward and forward and downward, respectively, and collides with a frontal collision input from the bumper beam. The load can be reliably transmitted to the central axis of the closed cross section of the bumper beam extension.

  According to the sixth aspect of the present invention, since the nut is inserted into the front fastening flange of the bumper beam extension, the bumper beam can be easily and firmly fastened to the bumper beam extension.

  According to the configuration of the seventh aspect, the temporary fixing protrusion is formed on the front bulkhead, and the temporary fixing hole that can be engaged with the temporary fixing protrusion is formed on the rear fastening flange. By engaging and temporarily fixing the bumper beam extension to the front bulkhead, the operation of fastening the front bulkhead and the bumper beam extension integrally to the front side frame can be facilitated.

  According to the configuration of claim 8, the vehicle width direction outer end of the mounting plate fixed to the front end of the front side frame is connected to the vehicle width direction outer surface of the front side frame by the brace member, and the bumper beam extension of the mounting plate is connected to the mounting plate. Since the outer rear fastening flange is connected, even if a collision load is input to the outer end in the vehicle width direction of the bumper beam extension due to a narrow offset frontal collision that collides with the front side frame in the vehicle width direction, the collision load is attached. It can be efficiently transmitted to the front side frame via the plate and the bracing member.

  According to the configuration of claim 9, the cross-sectional area of the closed cross-section and the sub-close cross-section gradually decreases from the inner side to the outer side in the vehicle width direction, so that the strut member bears at the time of offset frontal collision. While reducing the load, the collision load can be efficiently transmitted to the front side frame.

The perspective view of the vehicle body front part of a motor vehicle. (First embodiment) The perspective view of a front bulkhead and a shroud. (First embodiment) The disassembled perspective view of a shroud and cooling system components. (First embodiment) FIG. 4 is a four-direction arrow view of FIG. 1. (First embodiment) FIG. 5 is a view in the direction of arrows 5 in FIG. 4. (First embodiment) FIG. 6 is a sectional view taken along line 6-6 in FIG. (First embodiment) FIG. 7 is an enlarged view of part 7 of FIG. 1. (First embodiment) FIG. 8 is a cross-sectional view taken along line 8-8 in FIG. (First embodiment) The exploded perspective view of a bumper beam extension. (First embodiment) FIG. 10 is a view in the direction of arrow 10 in FIG. 7. (First embodiment) FIG. 11 is a sectional view taken along line 11-11 in FIG. 5; (First embodiment) FIG. 12 is a sectional view taken along line 12-12 in FIG. 5; (First embodiment) Explanatory drawing of the manufacturing method of a bumper beam extension. (First embodiment) The figure corresponding to FIG. (Second Embodiment)

First embodiment

  Hereinafter, a first embodiment 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.

  As shown in FIGS. 1 and 4, the hybrid vehicle of the embodiment includes a cabin 11 integrally formed in a bathtub shape with FRP (fiber reinforced resin), and an aluminum alloy is provided on the front surface of a dash panel 12 that stands from its front end. The pair of left and right suspension support members 13, 13 which are die-casted with the above are fixed. The suspension support members 13 and 13 include damper housings 13a and 13a that support upper ends of suspension dampers (not shown), and front side frame rear portions 13b and 13b that are connected to lower portions of the damper housings 13a and 13a and extend forward. A pair of left and right front side frame front parts 14, 14 made of an aluminum extruded material or a steel plate press material are connected to the front ends of the front side frame rear parts 13b, 13b. A pair of left and right CFRP side members 16, 16 are connected to front ends of a pair of left and right CFRP upper members 15, 15 extending forward from the upper left and right sides of the dash panel 12.

  A front bulkhead 17 made of a fiber reinforced resin, which is formed in a rectangular frame shape when viewed from the front, is fixed to the front ends of the front side frame front portions 14, 14, and the side members 16, 16 are attached to the left and right upper portions of the front bulkhead 17. The front end of is connected. A pair of left and right fiber reinforced resin bumper beam extensions 18, 18 are fixed to the left and right front surfaces of the front bulkhead 17, and fiber reinforced resin bumper beams extending in the vehicle width direction at the front ends of the bumper beam extensions 18, 18. 19 is fixed. The front surface of the bumper beam 19 is covered with a bumper face 20. A fiber reinforced resin shroud 21 formed in a rectangular frame shape when viewed from the front is disposed at a position surrounded by the front bulkhead 17, the bumper beam 19 and the pair of left and right bumper beam extensions 18, 18. The three cooling system components including the engine cooling radiator 22, the air conditioning condenser 23, and the battery cooling radiator 24 are overlapped and supported in the front-rear direction.

  Next, a support structure for cooling system components will be described with reference to FIGS. 1 to 3 and FIG. 6.

  The shroud 21 that supports the cooling system components includes an upper panel 31, a lower panel 32, and a pair of side panels 33 and 33 formed in a plate shape with fiber reinforced resin. That is, the upper panel 31 is fastened to the upper ends of the pair of side panels 33, 33 with two bolts 34, 34, respectively, and the lower panel 32 is connected to the lower ends of the pair of side panels 33, 33 with two bolts 35, By fastening at 35, the shroud 21 is formed in a duct shape with a rectangular cross section.

  The rearmost engine cooling radiator 22 has two support pins 22a and 22a projecting from the lower surface thereof fitted into a pair of rubber bushes 36 and 36 provided on the lower panel 32, and projecting from the upper surface. The two support pins 22 b and 22 b are supported between the upper panel 31 and the lower panel 32 by fitting into a pair of rubber bushes 37 and 37 provided on the upper panel 31.

  Similarly, the air conditioning condenser 23 located in front of the engine cooling radiator 22 is fitted with a pair of rubber bushes 38 provided on the lower panel 32 with two support pins 23a projecting on the lower surface. Further, the two support pins 23b, 23b protruding from the upper surface are fitted into a pair of rubber bushes 39, 39 provided on the upper panel 31, so that they are supported between the upper panel 31 and the lower panel 32.

  The battery cooling radiator 24 positioned in front of the air conditioning condenser 23 is lower in height than the engine cooling radiator 22 and the air conditioning condenser 23, and the two support pins 24 a and 24 a provided on the lower surface are provided on the lower panel 32. A pair of brackets 33a, 33a provided on the inner surfaces of the side panels 33, 33 are provided with two support pins 24b, 24b which are fitted to a pair of rubber bushes 40, 40 and protruded on the upper surface. By being fitted to the rubber bushes 41, 41, it is supported on the lower panel 32.

  In order to assemble the cooling system parts to the shroud 21, the engine cooling radiator 22, the air conditioning condenser 23 and the battery cooling radiator 24 are first assembled to the upper panel 31 and the lower panel 32, and then the upper panel 31 and the lower panel 32 are mounted on the vehicle. A pair of side panels 33, 33 are fastened with bolts 34, 35,. Thereby, compared with the case where the engine cooling radiator 22, the air conditioning condenser 23, and the battery cooling radiator 24 are assembled after the shroud 21 is assembled, the support pins 22a, 22a, 22b, 22b of the engine cooling radiator 22 are used. Engagement of the support pins 23a, 23a, 23b, 23b of the capacitor 23 and the support pins 24a, 24a of the battery cooling radiator 24 can be easily performed.

  In addition, since the battery cooling radiator 24 having a low height is disposed at the foremost side, the battery cooling radiator 24 is housed inside the bumper face 20 (see FIG. 1) to reduce the front-rear dimension of the front portion of the vehicle body. As well as reducing the width of the upper panel 31 in the front-rear direction relative to the width of the lower panel 32 (see FIG. 6), the upper part of the shroud 21 can be downsized to improve the mountability in the engine room. .

  Next, the structure of the bumper beam extension 18 will be described with reference to FIGS. 7 to 9 and FIGS. 11 to 13.

  The bumper beam extension 18 is configured by coupling the upper member 51 and the lower member 52. Since the upper member 51 and the lower member 52 have a substantially plane-symmetric structure, the structure will be described below with the upper member 51 as a representative. .

  The upper member 51 includes a core portion 53 made of continuous fiber reinforced resin, and a coating portion 54 made of discontinuous fiber reinforced resin that covers the entire outer surface and a part of the inner surface of the core portion 53. The continuous fiber reinforced resin is displayed in a dark color in the figure, and the discontinuous fiber reinforced resin is displayed in a light color in the figure.

  The upper member 51 in which the continuous fiber reinforced resin and the discontinuous fiber reinforced resin are laminated is manufactured as follows. As shown in FIG. 13A, a die 55 for press-molding the upper member 51 of the bumper beam extension 18 includes a female die 56 having a concave cavity 56 a for molding the outer surface of the upper member 51, and the upper member 51. Are formed in the cavity 56a and the core 57a, and grooves 56b, 57b,... Are formed in the cavity 56a and the core 57a. With the mold 55 opened, a first prepreg 58 of discontinuous fiber reinforced resin, a second prepreg 59 of continuous fiber reinforced resin, and a third discontinuous fiber reinforced resin are formed on the cavity 56a of the female mold 56. The prepreg 60 is disposed in a preheated state.

  The first, second, and third prepregs 58, 59, and 60 can use continuous fibers and discontinuous fibers such as glass fibers (glass fibers), carbon fibers, and aramid fibers. UD (sheets with continuous fibers aligned in one direction) or discontinuous fiber mats as reinforcement, semi-cured thermosetting resin (epoxy resin, polyester resin, etc.), or thermoplastic resin (nylon 6) And has a flexibility to adapt to the shape of the mold. In the case of a thermosetting resin, when a plurality of prepregs are inserted into a mold in a laminated state and heated to, for example, about 130 ° C. while applying pressure, the thermosetting resin is cured and a fiber reinforced resin product is obtained. . In the case of a thermoplastic resin, a plurality of preheated prepregs are inserted into a mold in a laminated state, subjected to pressure molding, and then cooled to obtain a fiber reinforced resin product.

  When the male mold 57 is lowered with respect to the female mold 56, the second prepreg 59 is pressed by the cavity 56a of the female mold 56 and the core 57a of the male mold 57, and the upper member 51 is molded. At this time, since the first and third prepregs 58 and 60 using the discontinuous fiber as a reinforcing material can be easily deformed, the first prepreg 58 sandwiched between the second prepreg 59 and the cavity 56a of the female die 56 is It flows into the grooves 56b ... of the cavity 56a, and the ribs on the outer surface of the upper member 51 are simultaneously formed and laminated in a thin film shape along the entire outer surface of the upper member 51. Similarly, the third prepreg 60 sandwiched between the second prepreg 59 and the core 57a of the male mold 57 flows into the grooves 57b of the core 57a, and simultaneously molds the rib on the inner surface of the upper member 51, The member 51 is laminated in a thin film shape along a part of the inner surface of the member 51 (part forming a closed cross section). And as shown in FIG.13 (B), the upper member 51 is completed by cut | disconnecting the excess part of the outer periphery of the product taken out from the metal mold | die 55. FIG.

  As shown in an enlarged circle in FIG. 9, the continuous fiber formed with the second prepreg 59 is reinforced with a plain weave of continuous fibers 61, 62, oriented in two orthogonal directions. The discontinuous fibers formed from the first and third prepregs 58 and 60 are reinforced with randomly entangled discontinuous fibers 63.

  Long fiber woven fabric and continuous fiber reinforced resin having UD as a reinforcing material have a relatively high strength, but because of the limited amount of deformation of woven fabric and UD, the moldability is low, and thin and high ribs, etc. Is difficult to mold. On the other hand, discontinuous fiber reinforced resin having short fibers that are randomly intertwined as a reinforcing material has a relatively low strength, but because the fibers are easily deformed, the moldability is high, and thin and high ribs are formed. Easy to do. Therefore, by laminating the discontinuous fiber reinforced resin on the outside of the continuous fiber reinforced resin and molding the upper member 51, the strength and moldability of the upper member 51 can be compatible.

  The upper member 51 molded as described above includes a main body 51a extending in the vehicle width direction while being bent in a substantially triangular shape in a plan view, and a front fastening that is bent upward from the front edge of the main body 51a. A flange 51b, a rear fastening flange 51c bent upward from the rear edge of the main body 51a, and four joints 51d to 51g extending in the front-rear direction at positions separated from each other in the vehicle width direction on the inner surface of the main body 51a. On the inner surface between the two joint portions 51d and 51e forming the closed section 18a, first reinforcing ribs 51h that intersect in three directions at intervals of 60 ° are formed of at least two discontinuous fibers in the front-rear direction (see FIG. 9). The same shape and arrangement as the first reinforcing ribs 52h), and the six second reinforcing ribs 51i, which extend in the front-rear direction and connect the front fastening flange 51b and the rear fastening flange 51c to the outer surface of the main body 51a. Formed with continuous fibers. Further, since it is a discontinuous fiber, three nuts 64 are easily inserted into the front fastening flange 51a, and one temporary fixing hole 51j and fastening hole are formed in the rear fastening flange 51c (see FIG. 9). ).

  Since the lower member 52 has the same shape that is substantially plane-symmetric with the upper member 51 described above, the same subscript as the subscript of each part of the upper member 51 is added to the reference numeral 52 of the lower member 52 so as to overlap. Description is omitted. The only difference between the upper member 51 and the lower member 52 is that the lower member 52 includes a plurality of pins 52k that protrude upward from the four joint portions 52d to 52g, whereas the upper member 51 includes the pins 52k. It is a point provided with the several pin hole 51m ... which can be fitted (refer FIG. 9).

  The upper member 51 and the lower member 52 having the above-described shapes are configured such that the pins 52k of the lower member 52 are fitted into the pin holes 51m of the upper member 51 so that the joint portions 51d to 51g and 52d to 52g are brought into contact with each other. In this state, the tips of the pins 52k... Are melted together with a vibrating tool from the upper member 51 side (see FIGS. 8 and 11). In this state, the rear fastening flanges 51c and 52c of the upper member 51 and the lower member 52 are linearly aligned in the vertical direction, but the front fastening flanges 51b and 52b of the upper member 51 and the lower member 52 are tilted forward. (See FIG. 11).

  The bumper beam extension 18 in which the upper member 51 and the lower member 52 are coupled to each other includes a rectangular cylindrical closed cross-sectional portion 18a that is located on the inner side in the vehicle width direction and extends in the front-rear direction, and an elliptic cylindrical shape adjacent to the outer side in the vehicle width direction. A first sub-closed cross-section portion 18b and an elliptical cylindrical second sub-closed cross-section portion 18c adjacent to the outside in the vehicle width direction are provided. The cross-sectional areas of the first and second sub closed cross-section portions 18b and 18c are equal to each other and are smaller than the cross-sectional area of the closed cross-section portion 18a. Further, the width in the front-rear direction of the substantially triangular bumper beam extension 18 in plan view is gradually narrowed from the inner side to the outer side in the vehicle width direction, so the length in the front-rear direction is the longest in the closed cross-sectional portion 18a, and then the second The 1st sub closed cross-section part 18b is long, and the 2nd sub closed cross-section part 18c is the shortest.

  As described above, the bumper beam extension 18 disposed between the front side frame front portion 14 and the bumper beam 19 connects the upper member 51 and the lower member 52 in which the continuous fiber reinforced resin and the discontinuous fiber reinforced resin are laminated. The first reinforcing ribs 51h, 52h are formed of a discontinuous fiber reinforced resin on the inner peripheral surface of the closed cross section 18a. When the impact load of the frontal collision is input from the bumper beam 19 to the bumper beam extension 18, the continuous fiber reinforced resin and the discontinuous fiber reinforced resin achieve both the strength and formability of the bumper beam extension 18. The closed cross section 18a is sequentially confirmed from the front end to the rear end while suppressing out-of-plane deformation. It is possible to increase the energy absorption performance by causing crush.

  The bumper beam extension 18 includes first and second sub closed cross-section portions 18b and 18c having a smaller cross-sectional area than the closed cross-section portion 18a on the outer side in the vehicle width direction of the closed cross-section portion 18a. Not only can shock absorption be performed in the first and second sub-closed cross-section portions 18b and 18c at the time of narrow offset frontal collision that collides more outwardly, but also shock absorption is performed by three closed cross-section portions juxtaposed in the vehicle width direction. In addition, the amount of energy absorption can be ensured while shortening the longitudinal dimension of the bumper beam extension 18.

  In addition, the pin 52k formed in the lower member 52 is fitted into the pin hole 51m formed in the upper member 51, and the tip of the pin 52k is melted to join the upper member 51 and the lower member 52. 51 and the lower member 52 can be combined with each other with high accuracy without loosening, and the upper member 51 and the lower member 52 can be prevented from separating at the time of a frontal collision, thereby ensuring the amount of energy absorption.

  In addition, discontinuous fiber reinforced resin front fastening flanges 51b and 52b and rear fastening flanges 51c and 52c are formed at the front and rear ends of the bumper beam extension 18, respectively. The front fastening flanges 51b and 52b and the rear fastening flanges 51c and 52c Since the second reinforcing ribs 51i... 52i of the same discontinuous fiber extending in the direction are connected to each other, the bumper beam extension 18 can be firmly coupled to the bumper beam 19 and the front side frame front portion 14 as well as a bumper beam against a collision load. The strength of the extension 18 can be increased to increase the reaction force, and the bumper beam extension 18 can be crushed with a short stroke to increase the amount of energy absorbed.

  Next, the structure of the front bulkhead 17 will be described with reference to FIGS. 2, 5, 7 and 10.

  The front bulkhead 17 made of fiber reinforced resin includes an upper member 71 and a lower member 72 extending in the vehicle width direction, and a pair of left and right side members 73 and 73 extending in the vertical direction, and two upper corner portions 74 and 74 and The two lower corner portions 75, 75 are combined in a rectangular frame shape when viewed from the front. The upper member 71 and the lower member 72 made of continuous fiber reinforced resin are linear members having a U-shaped cross section in which a pair of side walls 71a, 71a, 72a, 72a are connected by bottom walls 71b, 72b (see FIG. 2). . Basically, a wide portion 73b that is wide in the left-right direction is formed on the upper portion of the bottom wall 73a of the side member 73 made of continuous fiber reinforced resin, and the first side walls 73c, 73c stand rearward from the left and right side edges. At the same time, the second side walls 73d and 73d stand rearward from the upper and lower side edges. The second side walls 73d and 73d (portions shown in dark color in FIG. 2) are made of a resin different from other portions of the side member 73.

  The reason is that when the sheet-shaped prepreg is set in the mold and the side member 73 is molded, if both the first side walls 73c and 73c and the second side walls 73d and 73d are simultaneously molded with the same prepreg, The work of cutting or overlapping the prepregs of continuous fibers at those boundary portions is required and workability is lowered, but the above work is not required by configuring the second side walls 73d and 73d with another resin. This is because workability is improved.

  The upper corner portions 74, 74 and the lower corner portions 75, 75 made of discontinuous fiber reinforced resin are integrally connected in a rectangular frame shape, and there are an upper member 71, a lower member 72, and side portions made of continuous fiber reinforced resin. By joining the members 73 and 73 by welding or adhesion, a part of the upper member 71, the lower member 72, and the side members 73 and 73 are covered with discontinuous fiber reinforced resin. In particular, the left and right upper corner portions 74 are connected to each other by a discontinuous fiber reinforced resin connecting portion 76 extending in a band shape along the front surface of the bottom wall 71b of the upper member 71 (FIGS. 2, 5 and (See FIG. 7).

  The upper corner portion 74 includes a bottom wall 74a and side walls 74b and 74c that stand up from the edge so that the upper member 71 and the side member 73 are connected in cross section, and protrudes from the inner surface of the outer side wall 74b. The front end of the side member 16 is fastened with four bolts 78 to the nuts 77 inserted into the four fastening boss portions 74d provided (see FIGS. 7 and 10). First reinforcing ribs 74e, 74f, 74f are formed on the upper corner portion 74 along the portion (joining portion) where the end portions of the upper member 71 and the side member 73 are welded, and the fastening boss portions 74d. The two reinforcing ribs 74g ... are connected to the first reinforcing ribs 74e, 74f, 74f or the side wall 74c inside the upper corner 74 (see FIG. 10). The lower corner portion 75 is also formed with first reinforcing ribs along portions welded to the lower member 72 and the side member 73.

  On the rear surface of the upper member 71, third reinforcing ribs 76a ... made of discontinuous fiber reinforced resin are formed in a zigzag shape so as to connect the side walls 71a, 71a and bottom wall 71b made of continuous fiber reinforced resin. A plurality of pins 76 b projecting rearward from the discontinuous fiber reinforced resin coupling portion 76 on the front surface of the upper member 71 penetrate the bottom wall 71 b of the upper member 71 and are integrally connected to the third reinforcing ribs 76 a. (See FIG. 10). A plurality of discontinuous fiber reinforced resin mounting portions 74h, 76c,... Are formed on the upper surface of the upper side wall 74b of the upper corner portion 74 and the upper surface of the upper side wall 71a of the upper member 71. A device such as a horn bracket is attached to the nuts 79 inserted inside.

  Further, a pair of upper and lower temporary fixing protrusions 74i and 74i made of discontinuous fiber reinforced resin are projected from the front surface of the upper corner portion 74 of the front bulkhead 17 to the side member 73, and the temporary fixing protrusions 74i and 74i. Can be engaged with temporary fixing holes 51j and 52j formed in the rear fastening flange 51c of the upper member 51 and the rear fastening flange 52c of the lower member 52 of the bumper beam extension 18 (see FIGS. 7 and 12).

  A mounting plate 81 made of a metal plate is welded to the front end of the front side frame front portion 14, and a bracing member 82 made of a metal plate is attached to the vehicle width direction outer end of the mounting plate 81 and the vehicle width direction outer surface of the front side frame front portion 14. Are welded (see FIG. 2). In the state where the rear fastening flanges 51c and 52c of the bumper beam extension 18 are temporarily fixed to the side member 73 of the front bulkhead 17, six bolts 83 passing through the rear fastening flanges 51c and 52c from the front to the rear are attached to the mounting plate. The bumper beam extension 18 and the front bulkhead 17 are fastened together with the mounting plate 81 by screwing into weld nuts 84 provided on the rear surface of 81 (see FIGS. 7 and 11).

  At this time, the temporary fastening protrusions 74i, 74i protruding from the upper corner portion 74 and the side member 73 of the front bulkhead 17 are used as the rear fastening flange 51c of the upper member 51 and the rear fastening flange of the lower member 52 of the bumper beam extension 18. The bumper beam by the bolts 83 is fitted into the temporary fixing holes 51j, 52j formed in 52c, the temporary fixing projections 74i, 74i are melted with a vibration tool, and the bumper beam extension 18 is temporarily fixed to the front bulkhead 17. The fastening operation of the extension 18 and the front bulkhead 17 can be facilitated.

  Further, the vehicle width direction outer end of the mounting plate 81 fixed to the front end of the front side frame front portion 14 and the vehicle width direction outer surface of the front side frame front portion 14 are connected by a brace member 82, and the bumper beam extension 18 is connected to the mounting plate 81. Since the rear fastening flanges 51c and 52c are coupled, even when a collision load is input to the outer end in the vehicle width direction of the bumper beam extension 18 due to a narrow offset frontal collision, the collision load is transmitted via the mounting plate 81 and the bracing member 82. Thus, it can be efficiently transmitted to the front side frame front portion 14.

  The rectangular frame-shaped front bulkhead 17 includes a linear continuous fiber reinforced resin upper member 71, a lower member 72, and a pair of side members 73, 73, and discontinuous fiber reinforced connecting the end portions thereof. An upper corner portion 74, 74 and a lower corner portion 75, 75 made of resin are provided, and an upper member 71, a lower member 72 and a pair of side members 73, 73 made of continuous fiber reinforced resin having high strength, and molding The combination of the upper corner portions 74 and 74 and the lower corner portions 75 and 75 made of discontinuous fiber reinforced resin having excellent properties makes it possible to reduce the weight as compared with the conventional metal insert injection-molded product, as well as continuous fibers. Therefore, the front bulkhead 17 having high strength and rigidity can be obtained. In addition, the upper corner portion 74 and the lower corner portion 75 include the first reinforcing ribs 74e, 74f, and 74f along the joint portion between the upper member 71, the lower member 72, and the pair of side members 73 and 73. Further, the strength and rigidity of the front bulkhead 17 can be further enhanced by firmly integrating the lower corner portion 75 with the upper member 71, the lower member 72, and the pair of side members 73, 73.

  Further, the upper corner portion 74 of the front bulkhead 17 includes a fastening boss portion 74d for fastening the side member 16 and second reinforcing ribs 74g connected to the fastening boss portion 74d, so that the upper corner portion 74 and the side member 16 are provided. Thus, the collision load of the frontal collision can be efficiently transmitted from the front bulkhead 17 to the side member 16.

  Further, since the connecting portion 76 made of discontinuous fiber reinforced resin for connecting the left and right upper corner portions 74, 74 is formed along the upper member 71, the upper member 71 and the upper corner portions 74, 74 are integrated by the connecting portion 76. Not only can the strength of the front bulkhead 17 be increased, but the connecting portion 76 includes attachment portions 76c for attaching the in-vehicle components, so that the in-vehicle components can be easily attached using the upper member 71. . The upper member 71 has a U-shaped cross section in which a pair of side walls 71a and 71a are connected by a bottom wall 71b, and a third reinforcement that extends the pair of side walls 71a and 71a and the bottom wall 71b in a zigzag made of discontinuous fiber reinforced resin. Since the ribs 76a are connected to each other, the strength of the upper member 71 can be further increased by the third reinforcing ribs 76a, and the discontinuous fiber reinforced resin made from the connecting portion 76 of the upper member 71 and penetrating the bottom wall 71b is used. Since the pins 76b are integrated with the third reinforcing ribs 76a, the connecting portion 76 and the third reinforcing ribs 76a can be integrated with the pins 76b to further increase the strength of the upper member 71.

  Further, since the bumper beam extension 18 is fastened to the front surface of the wide portion 73b of the side member 73 of the front bulkhead 17, a bumper beam extension 18 that is long in the vehicle width direction is fastened to the front bulkhead 17 to cause a collision of narrow offset frontal collision. The load can be reliably transmitted to the front side frame front portion 14.

  Further, nuts 85 and 86 are inserted into the bottom wall 74a and the side member 73 of the upper corner portion 74 of the front bulkhead 17, respectively, and further, the nut 87 is attached to the overhanging portion 75a projecting forward from the lower member 72 of the front bulkhead 17. Is inserted (see FIG. 2). The nuts 85 and 86 are inserted into the bolts 88, 89 and 90 that pass through the side panel 33 of the shroud 21, and the nut 87 is inserted into the overhang 75 a that projects forward from the lower member 72 of the front bulkhead 17. The shroud 21 is fastened to the front bulkhead 17 by screwing.

  Since the side panel 33 of the shroud 21 is located outside the bumper beam extension 18 in the vehicle width direction, the side panel 33 made of fiber reinforced resin is removed when the bumper beam extension 18 is crushed by the collision load of the frontal collision of the vehicle. At the same time, the collision energy can be efficiently absorbed by crushing.

  As described above, the engine cooling radiator 22, the air conditioning condenser 23, and the battery cooling radiator 24 are supported inside the rectangular frame-shaped shroud 21, and are stretched forward from the lower portion of the rectangular frame-shaped front bulkhead 17. Since the lower portion of the shroud 21 is fastened to the protruding portions 75a and 75a, and the upper portion of the shroud 21 is fastened to the bottom walls 74a and 74a of the upper corner portions 74 and 74 of the front bulkhead 17, three cooling system components are previously attached to the shroud. Assembling performance of the cooling system parts and the shroud 21 can be improved by forming a sub-assembly by supporting the sub-assemblies and fastening the sub-assemblies together to the front bulkhead 17.

  In addition, the two bolts 91 and 91 penetrating the bumper beam 19 from the front to the rear are screwed into nuts 64... Inserted into the front fastening flanges 51 b and 52 b of the bumper beam extension 18, so that the bumper beam 19 is bumper beam. Fastened to the front ends of the extensions 18 and 18 (see FIG. 11). At this time, the rear portion of the bumper beam 19 is fitted into the recesses 33b and 33b formed on the front edges of the side panels 33 and 33 of the shroud 21, thereby reversing the position of the bumper beam 19 and reducing the overall length of the vehicle. In addition, the screwing operation of the bolts 91 and 91 can be facilitated by locking and temporarily holding the bumper beam 19 in the recesses 33b and 33b of the side panels 33 and 33.

  Further, the front fastening flanges 51 b and 52 b of the bumper beam extension 18 extend from the bumper beam 19 while being inclined forward and upward and downward from the joint portions 51 d to 51 g and 52 d to 52 g of the upper member 51 and the lower member 52, respectively. The collision load of the frontal collision can be reliably transmitted to the central axis of the closed cross section of the bumper beam extension 18. Moreover, since the nuts 64 are inserted into the front fastening flanges 51b, 52b of the bumper beam extension 18, the bumper beam 19 can be easily and firmly fastened to the bumper beam extension 18.

Second embodiment

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

  In the first embodiment, the first and second sub-closed cross-section portions 18b and 18c of the bumper beam extension 18 have the same cross-sectional area. In the second embodiment, the first sub-close cross-section portion 18b is It has an intermediate cross-sectional area between the closed cross section 18a and the second sub closed cross section 18c. That is, their cross-sectional areas gradually decrease from the closed cross-section portion 18a on the inner side in the vehicle width direction toward the second sub-closed cross-section portion 18c on the outer side in the vehicle width direction.

  This effectively transmits the collision load to the front side frame front part 14 while reducing the collision load borne by the bracing member 82 disposed on the outer side in the vehicle width direction of the front side frame front part 14 at the time of the offset frontal collision. can do.

  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, in the embodiment, the pin 52k is formed in the lower member 52 and the pin hole 51m is formed in the upper member 51, but the positional relationship may be interchanged.

14 Front side frame front (front side frame)
17 Front bulkhead 18 Bumper beam extension 18a Closed section 18b First sub closed section (sub closed section)
18c 2nd sub closed cross-section part (sub closed cross-section part)
19 Bumper beam 51 Upper member 51b Front fastening flange 51c Rear fastening flanges 51d to 51g Joint 51h First reinforcing rib (reinforcing rib)
51i Second reinforcing rib (reinforcing rib)
51j Temporary fixing hole 51m Pin hole 52 Lower member 52b Front fastening flange 52c Rear fastening flange 52d-52g Joint part 52h 1st reinforcement rib (reinforcement rib)
52i Second reinforcing rib (reinforcing rib)
52j Temporary fixing hole 52k Pin 64 Nut 74i Temporary fixing projection 81 Mounting plate 82 Bracing member

Claims (9)

A bumper beam extension (18) made of FRP is disposed between the front side frame (14) and the bumper beam (19), and the bumper beam extension (18) is a laminate of continuous fiber FRP and discontinuous fiber FRP. The upper member (51) and the lower member (52) are combined to form a closed section (18a) extending in the front-rear direction, and the front fastening flange of the discontinuous fiber FRP is formed at the front and rear ends of the bumper beam extension (18). (51b, 52b) and rear fastening flanges (51c, 52c), respectively, and reinforcing ribs (51i, 52i) extending in the front-rear direction through the front fastening flanges (51b, 52b) and the rear fastening flanges (51c, 52c). The front body structure of an automobile characterized by being connected in   With the pin (52k) formed on one of the upper member (51) and the lower member (52) fitted in the pin hole (51m) formed on the other, the tip of the pin (52k) is melted The vehicle body front structure according to claim 1, wherein the upper member (51) and the lower member (52) are coupled to each other.   The bumper beam extension (18) includes at least one sub closed cross section (18b, 18c) having a cross sectional area smaller than that of the closed cross section (18a) on the outer side in the vehicle width direction of the closed cross section (18a). The vehicle body front structure according to claim 1 or 2, wherein the vehicle body front structure is a vehicle body structure. The automobile according to any one of claims 1 to 3 , wherein reinforcing ribs (51h, 52h) are formed of discontinuous fibers FRP on the inner peripheral surface of the closed cross section (18a) . Body front structure.   The front fastening flanges (51b, 52b) extend from the joints (51d to 51g, 52d to 52g) of the upper member (51) and the lower member (52) so as to incline forward and downward, respectively. The vehicle body front part structure according to claim 4, characterized in that:   The vehicle body front structure according to claim 4 or 5, wherein a nut (64) is inserted into the front fastening flange (51b, 52b).   A temporary fixing protrusion (74i) is formed on the front bulkhead (17), and a temporary fixing hole (51j, 52j) that can be engaged with the temporary fixing protrusion (74i) is formed in the rear fastening flange (51c, 52c). The vehicle body front part structure according to any one of claims 4 to 6, wherein the vehicle body front part structure is a vehicle.   The mounting plate (81) fixed to the front end of the front side frame (14) is connected to the vehicle width direction outer end of the front side frame (14) with the bracing member (82), and the mounting plate The vehicle body front part structure according to any one of claims 4 to 7, wherein a rear fastening flange (51c, 52c) of the bumper beam extension (18) is coupled to (81). .   The cross-sectional area of the said closed cross-section part (18a) and the said sub closed cross-section part (18b, 18c) becomes small gradually from the inner side of a vehicle width direction to an outer side, The said of Claim 3 Auto body front structure.

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