JP2005067268A - Vehicle body front structure of cab-over vehicle - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a vehicle body front structure of a cab-over vehicle for efficiently securing a compartment space of a cab, especially a foot space of an occupant at collision of a vehicle. <P>SOLUTION: An upper bumper member 2 provided with an inclined part 2a standing from its top intermediate part toward an upper front part at a gradual inclined posture, and a horizontal part 2b extending forward in parallel to a front side member 1 from its front end is installed to the front side member 1 extending in parallel to a forward and backward direction of a cab-over vehicle, and the inclined part 2a is coupled with a bottom face of a toeboard part 30 at a front end of a cab floor 3, and designed to support the toeboard part 30. The horizontal part 2b is made to project forward from a compartment space blocked by a dash panel 4 standing from a front edge of the toeboard part 30, and the front end of the inclined part 2a of the upper member 2 is bridged with the front member 1 immediately under the end in a forward and backward direction. There is provided with a connecting member 5 for restraining the inclined part 2a of the upper member 2 from breaking at collision of the vehicle. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a vehicle body front structure of a cab over type vehicle.

  Conventionally, as disclosed in Patent Document 1, the front body structure of a cab-over type vehicle absorbs an impact by compressing and deforming in the axial direction at the front end of the left and right front side members extending in the vehicle longitudinal direction. And an upper member that extends forward and upward with the rear end coupled to the middle portion of the upper surface of the front side member. There is a structure in which a shock absorber is used to absorb a shock and the upper member is stretched to secure a vehicle compartment space.

  Further, in this type of vehicle body front structure, it is conceivable to provide an impact absorbing portion at the front end of the upper member in order to ensure the vehicle interior space more reliably. A representative example is shown in FIG. 5, and the front end of the front side member 1 is provided with an impact absorbing portion 1 b at a position protruding forward from the vehicle compartment space partitioned forward by the dash panel 4. The upper member 2 includes an inclined portion 2a that rises forward and upward from a middle portion of the upper surface of the front side member 1, and a horizontal portion 2b that extends forward in parallel with the front side member 1 from the front end of the inclined portion 2a. It has. The inclined part 2a of the upper member 2 is coupled to the lower surface of the toe board part 30 at the front end of the cab floor 3 to support the toe board part 30 from below. The horizontal portion 2 b of the upper member 2 is an impact absorbing portion similar to the front end of the front side member 1.

With the above structure, at the time of a vehicle front collision, the front side member 1 and the upper member 2 are both in front of the dash panel 4 and the impact absorbing portions 1b and 2b are both compressed and deformed in the axial direction to receive an impact. The vehicle interior space can be secured by absorbing and suppressing the amount of rearward movement and deformation of the dash panel 4 and the toe board 30.
Japanese Patent Publication No.54-24166

  However, in the conventional structure, when a large collision load is applied to the front side member 1 and the upper member 2 on one side, such as during an offset collision of the vehicle, the front side member 1 has its shock absorbing portion 1b as shown in FIG. However, in the upper member 2, the horizontal portion 2 b of the upper member 2 starts to compress and deform in the axial direction once under the impact load, but the rear portion of the inclined portion 2 a that supports the horizontal portion 2 b. A rotational force that pushes up the inclined portion 2a acts around the connecting portion with the front side member 1 at the end, and the inclined portion 2a may be bent upward from the intermediate portion by the rotational force. When the inclined portion 2a is bent, the shock absorption at the horizontal portion 2b is not reliably performed, and the rearward movement deformation amount of the toe board portion 30 and the dash panel 4 of the cab floor 3 is increased, so that the cabin space of the cab, particularly the occupant It becomes difficult to secure the foot space.

  Therefore, according to the present invention, even when a large collision load is applied to the front side member and the upper member, the front ends of both members can be reliably compressed and deformed in the axial direction to efficiently absorb the impact, and the dash panel and the cab floor An object of the present invention is to provide a vehicle body front structure of a cab-over type vehicle that can reliably secure a cabin space of the cab by suppressing the amount of rearward deformation of the toe board.

  The present invention provides a front side member that extends horizontally in the longitudinal direction of a cab-over type vehicle on a front side member, an inclined portion that rises from a middle portion of the upper surface forward and upward in a moderately inclined posture, and the front portion from the front end of the inclined portion. An upper member provided with a horizontal portion extending in parallel to the side member, the inclined portion of the upper member is coupled to the lower surface of the toe board portion at the front end of the cab floor, and the toe board portion is supported by the inclined portion; and In the vehicle body front structure of a cab-over type vehicle in which the horizontal portion protrudes forward from the passenger compartment space partitioned by the dash panel rising from the front edge of the toe board portion, the front end of the inclined portion of the upper member, A connecting member is provided to hang the front side member in the vertical direction. According to this, even if an upward rotational force acts on the inclined portion of the upper member at the time of a vehicle collision, the connecting member that connects the front side member and the upper member suppresses the vertical folding of the inclined portion of the upper member. . Therefore, the rearward movement deformation amount of the toe board portion and the dash panel of the cab floor does not increase, and the cabin space of the cab can be reliably ensured.

  The front end portion of the front side member and the horizontal portion of the upper member are shock absorbing portions that absorb the shock by compressing and deforming in the axial direction at the time of a vehicle collision, and are positioned immediately after both the shock absorbing portions of the front side member and the upper member. The connecting member is bridged (claim 2). In the event of a vehicle collision, since the inclined portion of the upper member is not deformed, the shock absorbing portion of the upper member can be reliably compressed and deformed in the axial direction, and the shock can be efficiently absorbed with the shock absorbing portion of the front side member. .

  According to the present invention, since the connecting member is provided between the front side member and the upper member of the cab over type vehicle so as to hang them up and down, even when a large collision load acts on the front side member and the upper member at the time of a vehicle collision, Without tilting the upper member in the vertical direction, the front ends of both members can be compressed and deformed in the axial direction to absorb shocks, reducing the amount of rearward deformation of the cab dash panel and cab floor toeboard. Thus, the cabin space of the cab, particularly the foot space of the occupant can be secured reliably and sufficiently. Further, since the upper member does not break at the inclined portion, the shock absorbing portion provided at the front end thereof is reliably compressed and deformed in the axial direction to efficiently absorb the shock.

  An embodiment of the present invention will be described with reference to FIGS. As shown in FIG. 1 (A), at the front of the cab-over type vehicle body, left and right front side members 1 that are skeleton members of the vehicle body that supports the cab are disposed in the vehicle longitudinal direction at a position below the cab floor 3 of the cab. It is extended. The cab floor 3 is provided with a step-down inclined step at the front and rear intermediate position. The front half of the floor is one step lower than the rear half of the floor on which the front seat S is installed, and the front seat is located at the front half of the floor. A toe board portion 30 is formed at the feet of the occupant seated in S. A space for an engine room and a wheel house is secured under the floor in the latter half of the floor. In addition, a vertical wall-shaped dash panel 4 that forms the front wall of the cabin space in the cab is erected on the front edge of the toe board portion.

  The left and right front side members 1 have the same structure, and one front side member 1 will be mainly described. As shown in FIGS. 1A and 1B, the front side member 1 has a closed cross-sectional structure including a member main body 11 having a substantially U-shaped cross section and an upper plate 12 that closes the upper opening. The general portion 1a of the front side member 1 directly below the cab floor 3 is provided with a reinforcement 13 that divides the closed cross section vertically along the longitudinal direction, thereby enhancing the rigidity.

  As shown in FIG. 1A and FIG. 3, the front end portion of the front side member 1 extending forward of the vehicle body from the dash panel 4 has a plurality of crashes at predetermined intervals in the front-rear direction on the side surface and the lower surface. The bead 14 is provided as an impact absorbing portion 1b that compresses and deforms in the axial direction and absorbs an impact when the vehicle collides.

  The front terminal of the front side member 1 is provided with a front cross member 6 that spans the left and right members 1 along the vehicle width direction. The front cross member 6 also serves as a bumper reinforcement. I try to support it. Reference numeral 16 in FIG. 1A denotes an upper control arm bracket that is provided on the side surface of the intermediate portion of the front side member 1 and supports the suspension of the front wheels.

  The front side member 1 is provided with an upper member 2 that branches forward and upward. The upper member 2 has a rear end 20 coupled to an intermediate portion in the front-rear direction of the front side member 1, an inclined portion 2a that rises upward and forward from the coupled portion, and a front end of the inclined portion 2a. A horizontal portion 2b that refracts and extends forward in parallel with the shock absorbing portion 1b at the front end of the front side member 1 is provided. The front terminal of the upper member 2 is aligned with the front terminal of the front side member 1.

  As shown in FIG. 2, the rear end 20 of the upper member 2 has a closed cross-sectional structure in which the upper opening of the member main body 21 having a substantially U-shaped cross section is closed by the upper plate 22. The rear end 20 is partly inserted into the member main body 11 of the portion having an open cross-sectional structure without providing the upper plate 12 from the front and rear intermediate positions of the front side member 1, and the rear end 20 of the upper member 2. The left and right side surfaces are overlapped with the inner surface of the front side member 1 and fixed by welding.

  As shown in FIG. 1B, in the inclined portion 2 a of the upper member 2, the member main body 21 is formed in an inverted hat shape in cross section, and the left and right side edge flanges are superposed on the lower surface of the toe board portion 30 of the cab floor 3. Thus, the toe board portion 30 forms a closed cross-sectional structure.

  As shown in FIG. 3, the horizontal portion 2 b of the upper member 2 has a closed cross-sectional structure with a member main body 21 and an upper plate 22. Similar to the shock absorbing portion 1b of the front side member 1, a plurality of crush beads 23 are provided on the side surface and the lower surface with a predetermined interval in the front-rear direction, and the impact is absorbed by compressive deformation in the axial direction at the time of a vehicle collision. It is as a shock absorbing part.

  The front end of the upper member 2 is provided with a front cross member 6a that spans the left and right members 2 along the vehicle width direction, like the front side member 1, and the front bumper is the same as the front cross member 6 of the front side member 1. B is supported.

  Between the front side member 1 and the upper member 2 configured in this way, as shown in FIGS. 1A and 1B, at positions immediately after the impact absorbing portions 1b and 2b of both members 1 and 2, Between the front end of the inclined portion 2a of the upper member 2 corresponding to the front edge of the toe board portion 30 of the cab floor 3 and the front end of the general portion 1a of the front side member 1 immediately below the connecting member 5 is extended vertically. . The connecting member 5 is made of a strip-shaped steel plate having a high thickness of 2.6 mm, and the connecting member 5 has a lateral width of about 30 mm. The upper and lower ends of the connecting member 5 are formed to be slightly wider than the intermediate portion, and a bolt through hole is formed at the center of both ends.

  The connecting member 5 has an upper end overlapped with an outer surface of the front end of the inclined portion 2a of the upper member 2, and a bolt member 51 penetrated through the bolt through hole is welded to the inside formed on the outer surface of the front end of the inclined portion 2a. While fastening to the screw hole having a nut, the lower end portion of the connecting member 5 is overlapped with the outer surface of the front end of the general portion 1a of the front side member 1, and the bolt is connected to the screw hole of the general portion 1a through the bolt through hole in the lower end portion. The member 51 is fixed by fastening.

  According to the present embodiment, when a large collision load acts on the front side member 1 and the upper member 2 on one side via the front bumper B, such as at the time of an offset collision of the vehicle, as shown in FIG. Then, between the barrier D and the general part 1a, the shock absorbing part 1b compresses and deforms in the axial direction to absorb the shock. In the upper member 2, the horizontal portion (impact absorbing portion) 2b starts to compress and deform in the axial direction between the barrier D and the inclined portion 2a, and the front end of the inclined portion 2a supporting the horizontal portion 2b is pushed up. Although the rotational force acts, the front end of the inclined portion 2a is connected to the rigid front side member 1 in the vertical direction by the connecting member 5, so that the above-described movement deformation of the front end of the inclined portion 2a is suppressed. Thereby, the horizontal part 2b reliably compresses and deforms in the axial direction and efficiently absorbs the impact. Depending on the magnitude of the collision load, the front end of the inclined portion 2a is slightly compressed and deformed in the axial direction, but the inclined portion 2a does not bend upward and rearward as in the conventional structure. Accordingly, the rearward deformation amount of the toe board portion 30 and the dash panel 4 of the cab floor 3 supported by the inclined portion 2a of the upper member 2 is much smaller than that of the conventional structure, and the cabin space of the cab, particularly the occupant A sufficient space can be secured at the feet.

  As a result of a collision experiment in which a vehicle having a conventional structure and a vehicle to which this embodiment is applied collide with an experimental offset deformable barrier at a speed of 64 km / h, the barrier intrusion into the foot space is about 270 mm in the conventional structure. On the other hand, in this embodiment, it decreased to about 230 mm.

  In the above-mentioned embodiment, although the connection member 5 was comprised with the steel plate, it is good not only as this but a wire member with high intensity | strength with respect to a tensile load.

1A is a schematic side view of a vehicle body front structure to which the present invention is applied, and FIG. 1B is a longitudinal sectional view taken along line IB-IB in FIG. 1A. It is a longitudinal cross-sectional view which follows the II-II line | wire of FIG. 1 (A). It is a longitudinal cross-sectional view which follows the III-III line | wire of FIG. 1 (A). It is a schematic side view which shows the state after the collision of the vehicle body front part structure of this invention. It is a schematic side view of the conventional vehicle body front part structure. It is a schematic side view which shows the state after the collision of the conventional vehicle body front part structure.

Explanation of symbols

1 Front side member 1b Front end (shock absorbing part)
2 Upper member 2a Inclined part 2b Horizontal part (shock absorbing part)
3 Cab floor 30 Toe board part 4 Dash panel 5 Connecting member

Claims (2)

A front side member that extends horizontally in the longitudinal direction of the body of a cab-over type vehicle, an inclined portion that rises in a gently inclined posture from the middle of the upper surface to the front and upward, and parallel to the front side member from the front end of the inclined portion An upper member having a horizontal portion extending forward is provided, the inclined portion of the upper member is coupled to the lower surface of the toe board portion at the front end of the cab floor, and the toe board portion is supported by the inclined portion, and the horizontal portion is In the vehicle body front structure of a cab-over type car that protrudes forward from the cabin space partitioned by a dash panel that stands up from the front edge of the toe board part,
A connecting member is provided to vertically extend the front end of the inclined portion of the upper member and the front side member immediately below the upper member, and the connecting member suppresses the inclined portion of the upper member from being bent in the vertical direction at the time of a vehicle collision. The front structure of the cab-over type car body.   The front end portion of the front side member and the horizontal portion of the upper member are shock absorbing portions that absorb the shock by compressing and deforming in the axial direction at the time of a vehicle collision, and are positioned immediately after both the shock absorbing portions of the front side member and the upper member. The front body structure of a cab-over type vehicle according to claim 1, wherein the connecting member is mounted.

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