JP2008006873A - Vehicle front body structure - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To improve vehicle body stiffness by a front end member having light weight and high strength. <P>SOLUTION: The front end member 16 constituted of a synthetic resin reinforced by carbon fibers has a first part 17 arranged in a vehicular lateral direction at a vehicle body center and connected to front ends of right and left front side frames 12, and a pair of right and left second parts 18 extending from both right and left ends of the first part 17 to a lateral outside rear side and connected to the center of right and left upper members 14; and formed in an arch shape in a plane view. The main aligning direction of the carbon fibers is made to be a direction along the arch. The front end member 16 has light weight and high strength as compared with a conventional one using glass fibers. In addition, the right and left side frames 12 and the right and left upper members 14 are securely connected to each other to improve the vehicle body stiffness, and the twisting of the vehicle body at the time of turning and the like is prevented to improve traveling stability. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention is a front end member made of a synthetic resin reinforced with carbon fiber, and connects the left and right front side frames with the left and right upper members disposed above the front side frame. It relates to the body structure.

The front end member, which is placed at the front end of the automobile body and supports the radiator and headlight, is made of thermoplastic resin reinforced with glass fiber to improve vibration fatigue characteristics and impact resistance, and to reduce costs. This is known from the following patent document 1.
Japanese Patent Laid-Open No. 11-152062

  By the way, since the conventional front end member uses glass fiber for reinforcing the synthetic resin, it is not only heavy but also has insufficient mechanical strength. In addition, the shape of the above-described conventional front end member is determined mainly to support components such as a radiator and a headlight, and in order to increase the rigidity of the vehicle body in cooperation with a frame member such as a front side frame of the vehicle body. The shape of the was not devised.

  The present invention has been made in view of the above circumstances, and an object of the present invention is to increase the rigidity of a vehicle body with a light-weight and high-strength front end member.

  In order to achieve the above object, according to the invention described in claim 1, a front end member made of a synthetic resin reinforced with carbon fiber is provided between the left and right front side frames and above the front side frame. A front body structure of a vehicle that connects between left and right upper members that are disposed, wherein the front end member is disposed in the left-right direction of the vehicle body at the center of the vehicle body and is connected to the front ends of the left and right front side frames. And a pair of left and right second portions that extend from the left and right ends of the first portion to the left and right outer rear sides and are connected to the middle portion of the left and right upper members, and are configured in an arch shape in plan view. A vehicle front body structure is proposed in which the main arrangement direction of the carbon fibers is the direction along the arch.

  According to the invention described in claim 2, in addition to the configuration of claim 1, the first portion includes a substantially horizontal upper wall, a front wall extending generally downward from a front edge of the upper wall, and A front vehicle body structure for a vehicle is proposed, which has a box structure having a pair of left and right side walls that extend in the longitudinal direction of the vehicle body and are connected to the left and right side edges of the upper wall and the front wall.

  According to the invention described in claim 3, in addition to the configuration of claim 1, the second portion has a generally horizontal upper and lower walls and a generally vertical space between the front edges of the upper and lower walls. A front wall that is connected in a direction, the upper wall is wider in the longitudinal direction of the vehicle body than the lower wall, and the upper wall extends from a connection portion with the upper member to a connection portion with the first portion. A vehicle front body structure is proposed in which the width in the longitudinal direction of the vehicle body increases.

  According to the invention described in claim 4, in addition to the structure of any one of claims 1 to 3, the carbon fiber in the surface layer of the front end member is formed of a metal that forms the front end member. A vehicle front body structure is proposed, which is arranged along a mold closing direction.

  According to the invention described in claim 5, in addition to the configuration of claim 2, the main arrangement direction of the carbon fibers along the lower edge of the front wall of the first part is the front end of the front side frame. A vehicle front body structure characterized by being directed is proposed.

  According to the invention described in claim 6, in addition to the structure of claim 1, a radiator support portion formed in a U shape with a synthetic resin reinforced with carbon fiber at the left and right ends of the first portion. A vehicle front body structure is proposed in which the left and right ends are connected and the main arrangement direction of the carbon fibers is the longitudinal direction of the radiator support portion.

  According to the invention described in claim 7, in addition to the configuration of any one of claims 1 to 6, the front end member is formed by laminating a plurality of sheets in which carbon fibers are arranged in parallel. A vehicle characterized in that an intermediate layer sheet having a different carbon fiber arrangement direction is laminated on at least two layers of sheets formed by molding a product with a mold and having the carbon fiber arrangement direction aligned. A front car body structure is proposed.

  The carbon yarn 22 of the embodiment corresponds to the carbon fiber of the present invention.

  According to the configuration of the first aspect, the front end member made of the synthetic resin reinforced with the carbon fiber is disposed in the left-right direction of the vehicle body at the center of the vehicle body and is connected to the front ends of the left and right front side frames. And a pair of left and right second parts that extend from the left and right ends of the first part to the rear of the left and right sides and are connected to the middle part of the left and right upper members. Since the main arrangement direction is the direction along the arch, it is not only lighter and stronger than a conventional front end member using glass fiber, but also the left and right front side frames and left and right front end members. The upper member is firmly connected to increase the rigidity of the vehicle body, and torsion of the vehicle body during turning, etc. is prevented to improve running stability, and the load at the time of vehicle collision is increased. It can be effectively transmitted to the front side frame and the upper member, and increasing the shock absorbing effect from Ntoendo member.

  According to the second aspect of the present invention, since the first portion of the front end member has a box structure having an upper wall, a front wall, and a pair of left and right side walls, the torsional rigidity of the vehicle body is particularly effectively increased. Can do.

  According to the third aspect of the present invention, the second portion of the front end member is composed of the upper wall, the lower wall, and the front wall, the upper wall is wider in the vehicle longitudinal direction than the lower wall, and the upper wall is the upper Since the width in the longitudinal direction of the vehicle body increases from the connecting portion with the member toward the connecting portion with the first portion, the vehicle body rigidity can be effectively increased by the second portion.

  According to the fourth aspect of the present invention, since the carbon fibers in the surface layer of the front end member are arranged along the mold closing direction of the mold for molding the front end member, the carbon fibers in the surface layer are formed when the mold is closed. It is possible to prevent the occurrence of defective molding due to being caught.

  According to the configuration of claim 5, since the main arrangement direction of the carbon fibers along the lower edge of the front wall of the first portion of the front end member is directed to the front end of the front side frame, the upper member is interposed via the front end member. In addition, the vehicle body rigidity can be increased by firmly integrating the front side frame.

  According to the structure of claim 6, the longitudinal direction of the radiator support portion formed in a U-shape and connected to the left and right ends of the first portion of the front end member is the main arrangement direction of the carbon fibers. Therefore, the rigidity of the radiator support portion can be increased.

  Further, according to the configuration of claim 7, when the front end member is formed by molding a multi-layered sheet of carbon fibers arranged in parallel with a mold, the carbon fibers are aligned in the same direction. In addition, since the intermediate layer sheets having different carbon fiber arrangement directions are laminated on the at least two layer sheets, deformation due to buckling is prevented when the molded front end member is taken out of the mold. be able to.

  Embodiments of the present invention will be described below with reference to the accompanying drawings.

  1 to 7 show an embodiment of the present invention. FIG. 1 is a perspective view of a skeleton at the front of a vehicle body of an automobile, FIG. 2 is a view taken in the direction of the arrow in FIG. 1, and FIG. FIG. 4 is a schematic view showing the arrangement direction of carbon yarns of the front end member, FIG. 5 is a perspective view of a sheet that is a material of the front end member, and FIG. 6 is a stack of sheets that are a material of the front end member FIG. 7 is a schematic diagram showing the arrangement direction of carbon yarns on the surface layer of the front end member.

  FIG. 1 shows a front frame structure of an automobile. Left and right front side frames 12 and 12 are arranged on the left and right sides of an engine room 11 in the longitudinal direction of the vehicle body, from the front ends of the left and right front pillars 13 and 13. The left and right upper members 14, 14 extend forward of the vehicle body. Upper members 14, 14 arranged on the outer sides in the left-right direction of the front side frames 12, 12 are inclined forward and downward from a position higher than the front side frames 12, 12, and their front ends are at the front ends of the front side frames 12, 12. They are connected by connecting members 15 and 15.

  A front end member 16 integrally formed with a synthetic resin reinforced with carbon fibers is disposed in front of the engine room 11. The front end member 16 extends in the left-right direction and is fixed to the front ends of the front side frames 12, 12. The front end member 16 extends obliquely from the left and right ends of the first portion 17 to the left and right outer rear sides, and extends upward. The left and right second portions 18 and 18 are fixed to the upper surface of the middle portion of the first and second portions 14, and the radiator support portion that supports the radiator 20 (see FIG. 2) by hanging downward in a U-shape from the left and right ends of the first portion 17. 19.

  As is apparent from FIGS. 1 to 3, the first portion 17 of the front end member 16 includes an upper wall 17a extending substantially horizontally, a front wall 17b extending substantially downward from the front edge of the upper wall 17a, and an upper wall 17a. The left and right side walls 17c and 17c connected to the left and right edges of the front wall 17b and extending in the front-rear direction generally constitute a box structure having high rigidity against torsional load. A hood lock support portion 17d that supports a hood lock (not shown) of the hood hood is provided at the center of the first portion 17 of the front end member 16.

  Each of the second portions 18 of the front end member 16 includes a front wall extending in a generally vertical direction so as to connect between the upper wall 18a and the lower wall 18b extending in a generally horizontal and parallel manner and the front edges of the upper wall 18a and the lower wall 18b. The front and rear width of the upper wall 18a is wider than the front and rear width of the lower wall 18b. Therefore, the second portion 18 is formed in a J shape in cross section.

  The upper wall 17a of the first portion 17 has the narrowest front-rear width at the central portion in the left-right direction, and the width widens rearward from the left in the left-right direction. Further, the upper walls 18a, 18a of the left and right second portions 18, 18 have the widest front-rear width of the portion connected to the side walls 17c, 17c of the first portion 17, and from there toward the portion connected to the left and right upper members 14, 14. The front-rear width gradually decreases. The upper wall 17a of the first portion 17 and the upper walls 18a, 18a of the second portions 18, 18 are connected on the same plane, and the shape thereof is an arch shape in which the central portion projects forward in plan view.

  The lower edge of the front wall 17b of the first portion 17 is curved in an inverted U shape, so that the vertical width of the front wall 17b is the narrowest at the center and the widest at the left and right ends connected to the side walls 17c and 17c. Yes. Further, the shape of the side walls 17c, 17c of the first portion 17 is a substantially right triangle in which the side connecting the rear edge of the upper wall 17a and the lower edge of the front wall 17b forms a hypotenuse. The first portion 17 is a portion where the left and right lower ends of the front wall 17a, the front lower ends of the side walls 17c and 17c, and the left and right ends of the radiator support portion 19 intersect, and is fixed to the front ends of the left and right front side frames 12 and 12. Is done.

  The carbon fibers used for the front end member 16 are long fibers having a length of 20 mm to 500 mm, and are used in the state of carbon yarns knitted in advance. FIG. 4 schematically shows the main arrangement direction of carbon yarns (carbon fibers) in each part of the front end member 16, and the carbon yarns are arranged along the longitudinal direction in any part. Particularly important is the arrangement direction of the carbon yarns in the upper wall 17a of the first portion 17, the upper portion of the front wall 17b of the first portion 17, and the left and right second portions 18, 18, along the longitudinal direction thereof. (See reference A). Further, the carbon yarn is arranged along the lower edge of the front wall 17a of the first portion 17, that is, so as to be directed to the connecting portion with the front ends of the left and right front side frames 12 and 12 (see reference B). Further, the U-shaped radiator support portion 19 is arranged so that the carbon yarn is along the longitudinal direction (see reference C).

  5 and 6 show a method of manufacturing the front end member 16.

  First, as shown in FIG. 5, a sheet 23 in which a large number of carbon yarns 22 are sewn in parallel on a synthetic resin film 21 is prepared, and this sheet 23 is cut into a predetermined shape, as shown in FIG. Stack several sheets. At this time, the main sheet 23 (1) having the largest number of main sheets 23 (1) in which the direction of the carbon yarn 22 is along the main arrangement direction is stacked, and the direction of the carbon yarn 22 is the main direction every predetermined number (three in the embodiment). The first and second intermediate sheets 23 (2) and 23 (3) intersecting the various arrangement directions are stacked so as to be sandwiched. The carbon yarns 22 of the first and second intermediate sheets 23 (2) and 23 (3) intersect the carbon yarn 22 of the main sheet 23 (1) in the 45 ° right direction and 45 ° left direction, respectively. . Further, the surface layer sheet 23 (4) located on the surface of the front end member 16 is arranged so that the direction of the carbon yarn 22 is along the mold closing direction of the mold.

  That is, the front end member 16 is manufactured by injection molding a synthetic resin in a state where the laminated sheet 23 is inserted into the cavity of the mold, but the carbon that rubs against the cavity surface when the mold is closed. The yarn 22 is arranged in parallel with the mold closing direction.

  This will be specifically described with reference to FIG. FIG. 7 schematically shows a part of a mold for forming the first portion 17 of the front end member 16. Of the lower mold 25 and the upper mold 26 of the mold 24, the mold closing direction indicated by the arrow P The front wall 17b of the parallel first portion 17 rubs against the cavity surface 25a of the lower mold 25 and the cavity surface 26a of the upper mold 26 when the mold is closed. At this time, if the arrangement direction of the carbon yarns 22 is not parallel to the mold closing direction, the carbon yarns 22 may be caught by the cavity surfaces 25a and 26a and the lamination of the sheets 23 may be broken.

  However, according to the present embodiment, the surface layer sheet 23 (4) is arranged so that the direction of the carbon yarn 22 is along the mold closing direction of the mold 24, so that the carbon yarn 22 is cavity surface 25a when the mold is closed. , 26a can be prevented, and the carbon yarn 22 can be prevented from being disturbed. The solid line arrows in FIG. 7 are the arrangement direction of the carbon yarns 22 on the surface layer, and the broken line arrow is the arrangement direction of the main carbon yarns 22.

  If the first and second intermediate sheets 23 (2) and 23 (3) are not interposed between the main sheets 23 (1), deformation caused by buckling when the molded front end member 16 is taken out from the mold 24. However, by interposing the first and second intermediate sheets 23 (2) and 23 (3), the buckling can be prevented and the molding accuracy of the front end member 16 can be improved.

  Since the front end member 16 molded in this manner uses carbon fibers for reinforcement, the front end member 16 is lighter and stronger than those using glass fibers. Moreover, since the carbon fiber is a long fiber of 20 mm to 500 mm, the strength can be further improved.

  Thus, a vertical load is input from the dampers of the left and right suspension devices to the middle part of the left and right upper members 14, 14 and the left and right are unbalanced. Although there is a problem of lowering the performance, according to the present embodiment, the front end member 16 firmly connects the left and right upper members 14 and 14 and the left and right front side frames 12 and 12, so The running performance can be improved by increasing to prevent torsional deformation of the vehicle body.

  At this time, since the first portion 17 of the front end member 16 has a box structure and the upper wall 18a of the second portion 18 having a wide width in the front-rear direction functions as a brace, the vehicle body rigidity is further increased. It can be increased effectively.

  When the vehicle collides head-on and a collision load directed toward the rear of the vehicle body acts on the front wall 17b of the first portion 17 of the front end member 16, the load is transferred from the front wall 17b of the first portion 17 to the left and right front side frames. 12 and 12 are directly transmitted to the front ends of the left and right upper members 14 and 14 via the first portion 17 and the second portion 18, and the front side frames 12 and 12 and the upper members 14 and 14 are connected to each other. It can be effectively crushed by a collision load to improve the shock absorbing performance.

  At this time, the main arrangement direction of the carbon yarns 22 along the lower edge of the front wall 17b of the first portion 17 of the front end member 16 is directed to the front side frames 12 and 12, and the front end member 16 is viewed in plan view. Since the main arrangement direction of the carbon yarns 22 is along the direction of the arch, the collision load is more effective on the front side frames 12 and 12 and the upper members 14 and 14. Can be transmitted.

  Further, when the hood hood is deformed so as to be bent upward at the time of a frontal collision, a large upward load acts on the center of the first portion 17 provided with the hood lock support portion 17d, but the arrangement of the carbon yarns 22 along the arch The upward deformation of the hood lock support portion 17d can be suppressed.

  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 number of main sheets 23 (1) and intermediate sheets 23 (2) and 23 (3) constituting the front end member 16 and the direction of the carbon yarn 22 are not limited to the embodiment.

Perspective view of the skeleton at the front of the car body 2 direction view of FIG. 3 direction arrow view of FIG. Schematic showing the arrangement direction of the carbon yarn of the front end member Perspective view of the seat used as the material for the front end member Schematic diagram showing the laminated state of the sheets used as the material for the front end Schematic showing the arrangement direction of the carbon yarn on the surface layer of the front end member

Explanation of symbols

12 Front side frame 14 Upper member 16 Front end member 17 First part 17a Upper wall 17b Front wall 17c Side wall 18 Second part 18a Upper wall 18b Lower wall 18c Front wall 19 Radiator support part 22 Carbon yarn (carbon fiber)
23 Sheet 24 Mold

Claims (7)

The front end member (16) made of a synthetic resin reinforced with carbon fibers (22), and left and right upper members (between the left and right front side frames (12) and above the front side frame (12)). 14) A vehicle front body structure for connecting between,
The front end member (16) includes a first portion (17) disposed in the left-right direction of the vehicle body at the vehicle body center portion and connected to the front ends of the left and right front side frames (12), and a first portion (17). A pair of left and right second portions (18) extending from the left and right ends to the left and right outer rear sides and connected to an intermediate portion of the left and right upper members (14), and configured in an arch shape in plan view, A front body structure of a vehicle, wherein a main arrangement direction of the fibers (22) is a direction along the arch.   The first portion (17) includes a generally horizontal upper wall (17a), a front wall (17b) extending substantially downward from a front edge of the upper wall (17a), the upper wall (17a) and the front wall (17b). 2. The front vehicle body structure of a vehicle according to claim 1, wherein the vehicle has a box structure having a pair of left and right side walls (17 c) extending in the longitudinal direction of the vehicle body.   The second portion (18) includes a substantially horizontal upper wall (18a) and a lower wall (18b) and a front wall that connects the front edges of the upper wall (18a) and the lower wall (18b) in a generally vertical direction ( 18c), the upper wall (18a) is wider in the vehicle longitudinal direction than the lower wall (18b), and the upper wall (18a) is connected to the upper member (14) from the connecting portion. The front body structure of a vehicle according to claim 1, characterized in that the width in the longitudinal direction of the vehicle body increases towards the connection with the first part (17).   The carbon fiber (22) on the surface layer of the front end member (16) is arranged along a mold closing direction of a mold (24) for molding the front end member (16). The front body structure of a vehicle according to any one of claims 1 to 3.   The main arrangement direction of the carbon fibers (22) along the lower edge of the front wall (17b) of the first part (17) is directed to the front end of the front side frame (12). Item 3. A front body structure of a vehicle according to Item 2.   The left and right ends of a radiator support portion (19) formed in a U shape with a synthetic resin reinforced with carbon fibers (22) are connected to the left and right ends of the first portion (17), and the carbon fibers (22) The vehicle front body structure according to claim 1, wherein a main arrangement direction is a longitudinal direction of the radiator support portion (19). The front end member (16) is formed by molding a multi-layered sheet (23) in which carbon fibers (22) are arranged in parallel with a mold (24), and the arrangement direction of the carbon fibers (22). The intermediate sheet (23) having a different arrangement direction of the carbon fibers (22) is laminated on at least two sheets (23) laminated in a uniform manner. The front body structure of a vehicle according to any one of the above.

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