CN115257941A

CN115257941A - Vehicle body structure

Info

Publication number: CN115257941A
Application number: CN202210014661.4A
Authority: CN
Inventors: 川端慎太郎; 吉冈秀真
Original assignee: Honda Motor Co Ltd
Current assignee: Honda Motor Co Ltd
Priority date: 2021-04-30
Filing date: 2022-01-07
Publication date: 2022-11-01
Also published as: JP7201736B2; JP2022170817A

Abstract

The invention provides a vehicle body structure which can improve the rigidity of the whole lower front panel including the periphery of a passage aiming at the load in the vehicle width direction. The vehicle body structure is provided with an inner cross member (24) on a cross member (20), wherein the cross member (20) is arranged on a lower dash panel (10) along a vehicle width direction within a range from a cab side surface to a Tunnel (TN), a closed cross section is formed on a panel surface of the lower dash panel (10), the inner cross member (24) extends along the vehicle width direction from a part of the lower dash panel (10) which is overlapped with a front side Frame (FS) in a front-rear direction to a groove wall part (TNb) of the Tunnel (TN) at a near side, and is connected with the groove wall part (TNb) and a footrest part (13) in a mode of crossing a floor tunnel ridge line (LTN 2) representing a boundary part of the groove wall part (TNb) and the footrest part (13).

Description

Vehicle body structure

Technical Field

The present invention relates to a vehicle body structure around an instrument panel that divides an engine compartment and a cab.

Background

A lower dash panel that defines an engine room and a cab in which a passenger sits in a front portion of the vehicle receives a load in a vehicle width direction from a front wheel or the like when the vehicle turns.

In order to prevent deformation of the dash panel due to such a load in the vehicle width direction, a cross member extending in the vehicle width direction is conventionally disposed at a lower portion of the dash panel constituting the vicinity of a floor surface of the cab.

However, a tunnel having a groove shape that opens downward in the front-rear direction at the vehicle width direction center portion is often disposed on the floor surface of the cab. Further, in the case where the tunnel is disposed on the floor surface, the cross member cannot be integrally configured in the vehicle width direction, but is disposed so as to be divided into two parts in the left and right direction with the tunnel interposed therebetween. Therefore, the portion of the dash panel where the cross member is divided cannot be increased in rigidity against the load in the vehicle width direction.

Therefore, patent document 1 proposes a structure in which a tunnel reinforcing member is disposed at the bottom of a channel, and left and right cross members are connected by the tunnel reinforcing member.

Documents of the prior art

Patent document

Patent document 1: japanese patent No. 6368851

Disclosure of Invention

Problems to be solved by the invention

However, although the configuration of patent document 1 can suppress the crushing of the groove bottom portion of the tunnel against the load in the vehicle width direction, there is room for improvement in suppressing the bending deformation and the collapse of the groove wall portion and the deformation of the connecting portion between the tunnel and the cab floor surface.

The present invention has been made in view of the above-described problems, and an object of the present invention is to provide a vehicle body structure capable of improving the rigidity of the entire lower cowl including the tunnel periphery with respect to a load in the vehicle width direction.

Means for solving the problems

In order to achieve the above object, a vehicle body structure according to the present invention includes: a lower dash panel that is provided with a panel body portion facing the front-rear direction of the vehicle and a footrest portion continuous with the lower side of the panel body portion, and that partitions an engine compartment and a cab; a tunnel having a downwardly open groove shape, one end portion of which is connected to a vehicle width direction center portion of the lower dash panel and extends in a vehicle front-rear direction at a cab floor portion; a cross member disposed on the lower dash panel in a vehicle width direction in a range from a cab side surface to the tunnel, the cross member forming a closed cross section on a panel surface of the lower dash panel; and a side frame that extends in a vehicle front-rear direction from an engine compartment interior to the cab floor portion and is supported by the lower dash panel, wherein the cross member includes an enlarged end portion that extends in a vehicle width direction from a portion of the lower dash panel that overlaps with the side frame in the front-rear direction to a groove wall portion of the tunnel, and that is joined to the groove wall portion and the cab floor portion so as to straddle a floor tunnel ridge line that represents a boundary portion between the groove wall portion and the cab floor portion.

Effects of the invention

According to the present invention, it is possible to provide a vehicle body structure capable of improving the rigidity of the lower cowl panel including the tunnel periphery against the load in the vehicle width direction.

Drawings

Fig. 1 is a front view showing a lower dash panel of an embodiment.

Fig. 2 is a perspective view illustrating a lower dash panel of an embodiment.

Fig. 3 is a perspective view illustrating an lower dash panel of an embodiment.

Fig. 4 is an enlarged front view of a main part of the lower dash panel showing an embodiment.

Fig. 5 is a sectional view taken along line V-V of fig. 2.

Fig. 6 is a sectional view taken along line VI-VI of fig. 2.

Fig. 7 is a sectional view taken along line VII-VII of fig. 2.

Fig. 8 is a sectional view taken along line VIII-VIII of fig. 2.

Description of the reference numerals

1. Vehicle body structure

10. Lower front coaming

11. Panel body

13. Footrest part

14b channel connecting parts (channel-shaped parts)

20. Cross beam

22. Joint extension

24. Inner beam (enlarged terminal part)

26a quadrangular section inclined plane (inclined plane)

26b front and rear faces (front and rear faces) of quadrangular section

27. Bifurcation surface

FS front side frame (side frame)

RL engine compartment

RC cab

TN channel

TNa trough bottom

TNb groove wall part

LTN2 floor passageway crest line

Detailed Description

An embodiment of a vehicle body structure 1 according to the present invention will be described in detail with reference to fig. 1 to 8.

In the description, the same elements are denoted by the same reference numerals, and redundant description thereof is omitted.

In the following description, unless otherwise specified, "front", "rear", "upper", "lower", "inner" and "outer" mean "front" and "rear" in the vehicle front-rear direction, "upper" and "lower" in the vehicle vertical direction, and "inner" and "outer" in the vehicle width direction.

The vehicle body structure 1 of the present embodiment is mainly configured by a tunnel TN extending in the vehicle longitudinal direction at the vehicle width direction center portion of the cab floor surface, and a lower dash panel 10 that partitions a cab RC and an engine compartment RL (see fig. 1 and 2).

The cab RC is set in the center of the vehicle, and is a space in which an occupant sits.

The engine compartment RL is set in a front portion of the vehicle, and is a space called an engine room, which mainly houses devices as a power source such as an engine.

The front side frame FS (side frame) is disposed in the engine compartment RL.

The front side frame FS (side frame) extends in the vehicle longitudinal direction from the inside of the engine compartment RL to the floor portion of the cab RC, and the rear end portion is joined to and supported by the dash panel 10.

The front side frame FS is provided with an engine (not shown) and other devices.

The passage TN has a groove shape that opens downward and extends in the vehicle front-rear direction (refer to fig. 1 and 2).

Further, a front end portion (one side end portion) of the tunnel TN is connected to and connected to a vehicle width direction center portion of the dash panel 10.

The duct TN includes a duct member TN1 and a duct introduction portion 14 (a panel side duct 14a, a duct connection member 14 b) arranged continuously in the front-rear direction.

The tunnel member TN1 and the tunnel introduction portion 14 (the panel-side tunnel 14a and the tunnel coupling member 14 b) are arranged so as to be coupled in the front-rear direction.

The vehicle body structure 1 according to the present embodiment can be configured substantially bilaterally symmetrically with respect to the tunnel TN, and similar operational effects can be obtained.

Therefore, in the following description, only the structure of the left side (driver seat side) will be described, and the description of the right side (passenger seat side) will be omitted.

The tunnel member TN1 has a groove shape that opens downward and extends in the vehicle front-rear direction.

The duct member TN1 has a front end portion connected to a rear end portion of the duct connecting member 14 b.

The lower dash panel 10 is formed of a plate-like member, and divides a cab RC and an engine compartment RL, and forms a lower portion of a front surface of the cab RC and is continuous with a floor surface of the cab RC (see fig. 1 to 3).

The lower dash panel 10 includes a panel body 11, a tunnel introduction portion 14 (a panel-side tunnel 14a, a tunnel connection member 14 b), a wheel house portion 12, a footrest portion 13 (a cab floor portion), and a cross member 20.

The panel main body 11, the footrest section 13, the wheel cover section 12, and the panel-side tunnel 14a constituting the lower dash panel 10 are integrally formed by press working 1 sheet of the plate material.

The panel body portion 11 has a substantially flat plate shape, and is provided upright in the vertical direction so as to face the vehicle front-rear direction in a range from the left end to the right end of the front surface of the cab.

The tunnel introduction portion 14 is set at a lower portion of the panel main body portion 11 in the vehicle width direction center.

The duct introducing portion 14 has a groove shape which is open downward, similarly to the duct member TN1 described above.

The duct introduction portion 14 constitutes a front end portion (one side end portion) of the duct TN and is continuous with the panel main body portion 11.

The duct introduction portion 14 is composed of a panel-side duct 14a and a duct connection member 14b (a member having a duct shape).

The panel side passages 14a are formed in the same member as the panel main body 11 by press working.

The channel connecting member 14b (member having a channel shape) is constituted by a plate-like member as a member independent from the panel-side channel 14 a.

The channel connecting member 14b is formed into a downward groove shape similar to the channel member TN1 by press working.

The duct coupling member 14b has its front end coupled and joined to the panel-side duct 14a, and has its rear end coupled and joined to the front end of the duct member TN 1.

The material and plate thickness of the plate-like member constituting the duct connecting member 14b are appropriately set.

Therefore, a material and a plate thickness different from those of the panel-side tunnel 14a (the lower dash panel 10) and the tunnel member TN1 can be used.

For example, a plate material harder than the panel-side passage 14a or a plate material having a larger plate thickness can be used.

With such a configuration, the rigidity of the channel introduction portion 14 can be improved.

The groove shape constituting the channel connecting member 14b (channel TN) is formed by the groove bottom TNa and the groove wall TNb.

The boundary between the groove bottom TNa and the groove wall TNb forms a ridge line (hereinafter referred to as a tunnel ridge line LTN 1) that is curved when viewed from the inside of the cab.

That is, the tunnel ridge line LTN1 extends substantially in parallel in the vehicle front-rear direction.

The groove bottom TNa constitutes a bottom portion of the groove shape and constitutes a ceiling portion of the passage TN.

Therefore, the tunnel bottom portion TNa extends in a belt shape substantially parallel to the floor surface to a position higher than the floor surface of the cab RC in the vehicle front-rear direction.

The groove wall portion TNb extends downward from the side edge portion of the groove bottom portion TNa.

That is, the groove wall portions TNb are a pair of wall surfaces that face in the vehicle width direction so as to extend along the vehicle front-rear direction and are disposed to face each other across the groove bottom portion TNa.

Further, groove wall portion TNb has its lower edge portion (groove-shaped opening edge portion) continuous with the floor surface of cab RC.

As viewed from the inside of the cab, a recessed ridge (hereinafter referred to as a floor tunnel ridge LTN 2) is formed at a boundary between the lower edge portion of the groove wall portion TNb and the floor surface of the cab RC.

That is, the floor tunnel ridge LTN2 extends substantially in parallel in the vehicle front-rear direction with the tunnel ridge LTN1 therebetween.

The wheel cover portions 12 are provided in a pair on the left and right sides of the outer peripheral edge portion in the vehicle width direction at a portion below the panel body portion 11 (see fig. 2 and 3).

The wheel cover portion 12 constitutes a part of a wheel cover (not shown) that houses left and right front wheels (not shown).

The wheel house 12 is curved so as to accommodate left and right front wheels (not shown) for steering, and has a substantially 1/8 spherical shape.

A footrest section 13 (cab floor section) is provided between the tunnel introduction section 14 and the left and right wheel house sections 12 in the vehicle width direction (see fig. 2 and 3).

The footrest section 13 connects a lower portion of the panel body 11 in the vehicle longitudinal direction to the cab floor surface.

The footrest section 13 has its front edge portion continuous with the lower edge portion of the panel main body 11 and is slightly inclined rearward and downward with respect to the horizontal plane.

Therefore, when viewed from the inside of the cab, a concave ridge (hereinafter referred to as a panel ridge L10) is formed at the boundary between the footrest section 13 and the panel body section 11.

The cross member 20 is disposed on the inner panel surface of the dash panel 10 in the vehicle width direction in a range from the cab side surface (outer edge portion in the vehicle width direction) to the groove wall portion TNb of the panel-side tunnel 14a (see fig. 1 and 2).

The cross member 20 is disposed so as to extend from the panel main body portion 11 to a portion on the lower dash panel 10 of the footrest portion 13 in the vehicle front-rear direction.

That is, the cross member 20 is disposed on the dash panel 10 so as to straddle the panel ridge line L10 in the vehicle front-rear direction.

The cross member 20 is formed of a member separate from the plate-like member forming the lower dash panel 10 (the panel body 11, the wheel house 12, and the footrest section 13).

The cross member 20 is provided as a reinforcing member on the lower dash panel 10, and forms a closed cross section together with the lower dash panel 10.

The beam 20 is composed of an outer beam 21 and an inner beam 24 (enlarged end portion).

The outer cross member 21 and the inner cross member 24 are formed of different members.

The outer cross member 21 is disposed from the cab side surface (outer edge portion in the vehicle width direction) to a portion of the panel main body 11 that supports the front side frame FS.

The outer cross member 21 forms a closed cross section together with the lower dash panel 10 (see fig. 1 and 2).

The outer cross member 21 includes an outer member body 21a, a joint extension 22, and an outer member flange 23.

The outer member main body 21a, the joint extension 22, and the outer member flange 23 are formed integrally by pressing 1 plate-like member in the same member.

Thereby, the outer cross member 21 is formed in a T shape.

The outer member main body 21a is curved along the shape of the wheel house portion 12 at the boundary portion between the wheel house portion 12 and the footrest portion 13, and is disposed so as to straddle the ridge line of the boundary portion.

The outer member main body 21a extends in the vehicle width direction along the plate surface of the panel main body 11 at the boundary between the panel main body 11 and the footrest section 13, and is disposed so as to straddle the ridge line at the boundary.

The outer member body 21a includes outer body upper and lower surfaces 21b and outer body front and rear surfaces 21c.

The outer body upper and lower surfaces 21b extend in a state facing the vertical direction along the curved surface of the wheel cover portion 12 and the plate surface of the lower portion of the panel body portion 11, and are substantially parallel to the plate surface of the front end portion of the footrest portion 13.

The outer body front-rear surface 21c extends substantially parallel to the plate surfaces of the lower end portion of the wheel house portion 12 and the lower end portion of the panel body portion 11 while facing the front-rear direction.

The outer member body 21a is formed in a substantially L-shaped cross section by the outer body upper and lower surfaces 21b and the outer body front and rear surfaces 21c.

In addition, a corner portion of the substantially L-shaped cross section forms a ridge line (outer member ridge line L21) that is folded in a convex manner when viewed from the inside of the cab.

The joint extension 22 is formed in a groove shape having a substantially isosceles trapezoidal cross section that opens forward (see fig. 6).

The joint extension portion 22 is set at a portion of the panel main body portion 11 (lower dash panel 10) that overlaps with the front side frame FS in the plate thickness direction.

The joint extension 22 extends from the outer member body 21a along the front side frame FS.

The joining extension portion 22 includes extension front and rear surfaces 22a and extension left and right surfaces 22b.

The extended front-rear surface 22a faces the front-rear direction and extends in the up-down direction along the plate surface of the panel body 11.

The extended left and right surfaces 22b are a pair of left and right plate surfaces that are disposed facing each other in the vehicle width direction and are disposed on the panel body 11.

The extended right and left surfaces 22b are erected from the vehicle width direction side edge portions of the extended front and rear surfaces 22a toward the panel main body 11.

The extension left and right surfaces 22b are set such that the distance between the extension front and rear surfaces 22a and the plate surface of the panel body 11 becomes smaller as the extension front and rear surfaces 22a are joined to the front end side (upper side) of the extension portion 22.

The closed cross section formed by the joint extension portion 22 is continuous with the closed cross section formed by the outer cross member 21, and 1 space is formed.

The outer member flange 23 is set as a joint portion when the outer cross member 21 is joined to the dash panel 10, and is provided at a peripheral edge portion of the outer member main body 21a and the joint extension 22.

Then, the outer member flange 23 is joined to the lower dash panel 10 by spot welding or the like, whereby the cross member 20 is provided integrally with the lower dash panel 10.

The inner cross member 24 is provided along the vehicle width direction, and forms a closed cross section together with the dash panel 10 (see fig. 1, 2, 4, and 5).

The inner cross member 24 is provided so that its vehicle width direction outer end portion overlaps the vehicle width direction inner end portion of the outer cross member 21.

The inner cross member 24 has its vehicle-width-direction inner end joined to the groove wall portion TNb and the groove bottom portion TNa of the panel-side tunnel 14a constituting the tunnel TN.

Inboard beam 24 includes an inboard member body 24a and an inboard member flange 28.

The inner member main body 24a and the inner member flange 28 are formed integrally in the same member by press working 1 plate-like member.

The inner member body 24a includes a triangular cross-section 25 and a quadrangular cross-section 26.

The inner member body 24a has the triangular cross-sectional portion 25 positioned on the outer side in the vehicle width direction and the quadrangular cross-sectional portion 26 positioned on the inner side in the vehicle width direction, and the triangular cross-sectional portion 25 and the quadrangular cross-sectional portion 26 are formed continuously in the vehicle width direction.

The triangular cross-sectional portion 25 forms a closed cross section having a substantially triangular cross section together with the lower dash panel 10 (see fig. 8).

The triangular cross-section portion 25 includes triangular cross-section portion upper and lower surfaces 25a and triangular cross-section portion front and rear surfaces 25b.

The triangular cross-section upper and lower surfaces 25a face in the vertical direction, and the front edge side thereof extends inward in the vehicle width direction from the inner end of the outer main body upper and lower surfaces 21b along the lower plate surface of the panel main body 11.

The triangular cross-section front-rear surface 25b faces the front-rear direction, and the lower edge side thereof extends from the inner end of the outer main body front-rear surface 21c to the inside in the vehicle width direction along the plate surface of the front edge portion of the footrest section 13.

The triangular cross-section front-rear surface 25b is continuous from the upper edge thereof to the rear edge of the triangular cross-section upper-lower surface 25 a.

Thus, the triangular cross-section 25 has a substantially L-shaped cross section formed by the triangular cross-section upper and lower surfaces 25a and the triangular cross-section front and rear surfaces 25b.

In addition, when viewed from the inside of the cab, a corner portion having a substantially L-shaped cross section forms a ridge line of a convex fold (hereinafter, this ridge line is referred to as a triangular cross-section ridge line L25).

The portion of the lower dash panel 10 where the triangular cross-sectional portion 25 is provided is gently curved and continuous from the panel body 11 toward the footrest section 13, and does not form a sharp ridge line.

Thus, the closed cross-sectional shape formed by the panel and the triangular cross-sectional portion 25 is formed into a substantially triangular shape in side view.

The quadrangular cross-sectional portion 26 forms a closed cross section having a substantially parallelogram shape in cross section together with the lower dash panel 10 (see fig. 6 and 7).

The quadrangular cross-section portion 26 includes a quadrangular cross-section portion inclined surface 26a (inclined surface), a quadrangular cross-section portion front-rear surface 26b (front-rear surface), and a bifurcation surface 27.

The front edge side of the quadrangular cross-sectional portion inclined surface 26a (inclined surface) extends straight along the inner end of the triangular cross-sectional portion upper and lower surfaces 25a toward the passage ridge line LTN1 of the panel-side passage 14a on the lower plate surface of the panel main body 11.

That is, the quadrangular cross-sectional portion inclined surface 26a is linearly inclined so as to become higher as going from the outside toward the inside in the vehicle width direction.

The quadrangular cross-sectional portion inclined surface 26a is set to have a height such that the vehicle width direction inner end thereof is positioned at the groove bottom portion TNa of the passage TN.

The quadrangular cross-sectional portion front-rear surfaces 26b (front-rear surfaces) face in the vehicle front-rear direction, and the lower edge sides thereof extend inward in the vehicle width direction from the inner end portions of the triangular cross-sectional portion front-rear surfaces 25b along the plate surface of the front edge portion of the footrest section 13.

The front and rear surfaces 26b of the quadrangular cross section extend substantially parallel to the plate surface of the lower end portion of the panel body 11.

The front and rear surfaces 26b of the quadrangular cross-sectional portion are continuous at the upper edge with the rear edge of the inclined surface 26a of the quadrangular cross-sectional portion.

Thus, the quadrangular cross-sectional portion 26 has a substantially L-shaped cross section formed by the quadrangular cross-sectional portion inclined surface 26a and the quadrangular cross-sectional portion front and rear surfaces 26 b.

In addition, a corner portion of the substantially L-shaped cross section forms a ridge line of a convex fold when viewed from the inside of the cab (hereinafter, this ridge line is referred to as a quadrangular cross section portion ridge line L26).

The vehicle-width-direction inner edges of the front and rear surfaces 26b with a quadrangular cross section extend in the vertical direction along the groove wall TNb of the panel-side tunnel 14 a.

With the above configuration, the quadrangular cross-sectional portion 26 has a substantially triangular shape divided by the quadrangular cross-sectional portion inclined surface 26a, the groove wall portion TNb, and the footrest portion 13 (cab floor portion) when viewed from the rear.

The quadrangular cross-sectional portion edge line L26 is bifurcated at the vehicle width direction inner end portion into a bifurcation front side edge line L27a and a bifurcation rear side edge line L27b, and a bifurcation surface 27 is disposed between the bifurcation front side edge line L27a and the bifurcation rear side edge line L27 b.

The triangular cross-sectional portion edge line L25, the quadrangular cross-sectional portion edge line L26, the branch front side edge line L27a, and the branch rear side edge line L27b are collectively referred to as an inner member edge line L24.

The quadrangular cross-sectional portion 26 is provided at a portion of the lower dash panel 10 where the panel body 11 and the footrest portion 13 are continuous in the vehicle front-rear direction.

At this portion, the lower dash panel 10 is bent into a substantially L-shaped cross section, and a concave ridge (hereinafter, this ridge is referred to as a panel ridge L10) is formed as viewed from the interior of the cab.

That is, the quadrangular cross-sectional portion 26 is provided so as to straddle the panel ridge line L10.

Thus, the closed cross section formed by the panel body portion 11, the footrest portion 13, and the quadrangular cross section portion 26 has a substantially parallelogram cross sectional shape in side view (see fig. 7).

The quadrangular cross-sectional portion 26 is provided in a region on the lower dash panel 10 where the panel body 11 and the groove wall portion TNb of the panel-side tunnel 14a are continuous in the vehicle width direction.

That is, the quadrangular cross-sectional portion 26 is disposed so as to straddle the ridge line of the concave fold when viewed from the inside of the cab.

As a result, the closed cross section formed by the panel body 11, the groove wall TNb of the panel-side passage 14a, and the quadrangular cross section portion 26 has a substantially parallelogram shape in plan view (see fig. 6).

The bifurcation surface 27 is sandwiched between the quadrangular cross-sectional portion inclined surface 26a and the quadrangular cross-sectional portion front and rear surfaces 26b to form a substantially triangular shape, and is disposed at the vehicle width direction inner end portion of the quadrangular cross-sectional portion 26 (see fig. 4).

That is, the quadrangular cross-sectional portion edge line L26 is disposed between the branch front side edge line L27a and the branch rear side edge line L27b such that the vehicle width direction inner side end portion thereof is divided into the branch front side edge line L27a and the branch rear side edge line L27 b.

In addition, the bifurcate surface 27 extends along the bottom surface of the groove bottom TNa of the panel-side passage 14 a.

The inner member flange 28 is set as a joint portion at the time of joining the inner cross member 24 and the dash panel 10, and is provided at a peripheral edge portion of the inner member main body 24a (see fig. 4).

Further, the inner member flange 28 is joined to the dash panel 10 by spot welding or the like, whereby the inner cross member 24 is provided integrally with the dash panel 10.

The inner member flange 28 is provided so that its outer edge in the vehicle width direction overlaps the outer member flange 23 of the outer cross member 21 located at the inner edge in the vehicle width direction.

That is, the inner cross member 24 is provided such that the vehicle width direction outer end thereof overlaps the vehicle width direction inner end of the outer cross member 21.

Next, the operation and effects of the present embodiment will be described.

In the vehicle body structure 1 of the present embodiment, the inner cross member 24 (enlarged terminal end portion) extends in the vehicle width direction from a portion of the dash panel 10 that overlaps the front side frame FS (side frame) to the groove wall portion TNb of the panel side tunnel 14 a.

In addition, in the vehicle body structure 1 of the present embodiment, the cross member 20 is provided so as to straddle the floor tunnel ridge line LTN 2.

Thus, when a load in the vehicle width direction is input to the lower dash panel 10, the inner cross member 24 functions as a pillar and a resisting wall, and the rigidity of the base portion of the tunnel TN can be improved.

Further, when a load in the vehicle width direction (hereinafter referred to as a lateral load) from the front side frame is input to the lower dash panel 10 at the time of turning or the like, the bending deformation of the base portion of the tunnel TN can be suppressed.

In the vehicle body structure 1 of the present embodiment, the vehicle width direction inner end of the quadrangular cross-section inclined surface 26a (inclined surface) is located at the height of the groove bottom TNa of the tunnel TN, and is linearly inclined so as to become higher as going from the vehicle width direction outer side to the inner side.

Accordingly, since rigidity continuity can be ensured in the vehicle width direction even with the tunnel TN interposed therebetween, a lateral load input to the cab floor portion can be transmitted to the groove bottom portion TNa of the tunnel TN.

Further, since the groove bottom portion TNa of the tunnel TN is formed by a flat surface along the horizontal direction, a load (lateral load) in the vehicle width direction is input in the form of a shear load.

This can further increase the rigidity of the base portion of the channel TN.

In the vehicle body structure 1 of the present embodiment, the quadrangular cross-sectional portion front-rear surface 26b (the front-rear surface of the enlarged end portion) has a substantially triangular shape divided by the quadrangular cross-sectional portion inclined surface 26a (inclined surface), the groove wall portion TNb, and the footrest portion 13 (cab floor portion).

This can further increase the rigidity of the base portion of the channel TN.

In the vehicle body structure 1 of the present embodiment, the quadrangular cross-sectional portion 26 (enlarged end portion) is arranged so as to form a closed cross section having a substantially parallelogram shape in cross section together with the quadrangular cross-sectional portion inclined surface 26a, the quadrangular cross-sectional portion front-rear surface 26b, the groove wall portion TNb, and the panel main body portion 11.

This can suppress the amount of projection of the cross member 20 toward the cab side, and improve the rigidity in the vehicle vertical direction and the rigidity in the vehicle width direction.

In the vehicle body structure 1 of the present embodiment, the diverging surfaces 27 are disposed so as to be sandwiched by the quadrangular cross-sectional portion front-rear surfaces 26b (the front-rear surfaces of the enlarged end portions) and the quadrangular cross-sectional portion inclined surfaces 26a (the inclined surfaces).

This makes it possible to more effectively transmit the input lateral load to the groove bottom portion TNa of the tunnel TN while maintaining the substantially parallelogram shape in cross section formed by the quadrangular cross-section portion 26 and the cowl panel 10.

In the vehicle body structure 1 of the present embodiment, the quadrangular cross-sectional portion 26 (enlarged end portion) is disposed so as to straddle a portion where the panel body 11 and the footrest section 13 are continuous.

This allows the lateral load transmitted along the panel ridge line L10 to be transmitted to the groove bottom portion TNa side of the passage TN.

Further, the lateral load transmitted to the groove opening of the passage TN can be reduced, and the collapse of the passage TN can be suppressed.

In the vehicle body structure 1 of the present embodiment, the tunnel introduction portion 14 is constituted by the panel-side tunnel 14a and the tunnel coupling member 14b (member having a tunnel shape).

This can suppress the amount of contraction of the duct introduction portion 14 of the lower dash panel 10, and therefore can improve the workability during press working.

Further, by making the tunnel connecting member 14b a member separate from the panel body 11, it is possible to use a member having a material and a shape that can further improve the rigidity of the tunnel TN.

In the vehicle body structure 1 of the present embodiment, the cross member 20 is composed of two members, i.e., the outer cross member 21 and the inner cross member 24, and the outer cross member 21 and the inner cross member 24 are joined by spot welding or the like.

This makes it possible to reduce the size of the die for pressing the cross member 20, thereby improving productivity.

The present invention is not limited to the cross member 20 including 2 members, i.e., the outer cross member 21 and the inner cross member 24.

For example, the outer cross member 21 may be divided into 3 parts together with the inner cross member 24 on the wheel house 12 side and the joint extension 22 side.

In addition, the same operational effects as those of the present embodiment can be obtained by adopting such a configuration.

In the vehicle body structure 1 of the present embodiment, the cross member 20 includes a joint extension 22 extending from the outer member body 21a along the front side frame FS at a portion of the panel body portion 11 (the lower dash panel 10) that overlaps with the front side frame FS in the plate thickness direction.

Accordingly, the load input from the front side frame FS can be transmitted to the cross member 20, and therefore, deformation of the lower dash panel 10 at the time of load input can be suppressed.

In the vehicle body structure 1 of the present embodiment, the joint portion between the panel-side tunnel 14a and the tunnel connecting member 14b (member having a tunnel shape) is set so as to overlap the joint portion between the inner member flange 28 and the groove wall portion TNb.

Thus, since the plate thickness of the joint portion is increased, the rigidity against the lateral load can be improved without increasing the number of components and the weight.

In the vehicle body structure 1 of the present embodiment, the engine compartment RL is set in front of the cab RC, but the present invention is not limited to this embodiment.

For example, similar operational effects can be achieved by adopting a configuration in which the engine compartment is set behind the cab RC and the cross member 20 of the present embodiment is disposed on the lower dash panel 10 that divides the cab RC and the engine compartment.

Claims

1. A vehicle body structure characterized by comprising:

a lower dash panel that is provided with a panel main body portion facing the front-rear direction of the vehicle and a footrest portion continuous below the panel main body portion, and that partitions an engine compartment and a cab;

a tunnel having a downwardly open groove shape, one end portion of which is connected to a vehicle width direction center portion of the lower dash panel and extends in a vehicle front-rear direction at a cab floor portion;

a cross member disposed on the lower dash panel in a vehicle width direction in a range from a cab side surface to the tunnel, the cross member forming a closed cross section on a panel surface of the lower dash panel; and

a side frame extending in the vehicle front-rear direction from the inside of the engine compartment to the cab floor and supported by the lower dash panel,

the cross member includes an enlarged terminal portion that extends in the vehicle width direction from a portion of the lower dash panel that overlaps the side frame in the front-rear direction to a groove wall portion of the tunnel, and that is joined to the groove wall portion and the footrest portion so as to straddle a floor tunnel ridge line that represents a boundary portion between the groove wall portion and the cab floor portion.

2. The vehicle body structure according to claim 1,

the expansion terminal section includes:

front and rear faces that face in the vehicle front-rear direction; and

an inclined surface which is positioned between the dash lower panel and the front and rear surfaces and has a panel surface inclined obliquely with respect to the vehicle width direction,

the vehicle width direction inside end of the inclined surface is located at the height of the groove bottom of the duct, and is inclined linearly so as to increase from the vehicle width direction outside toward the inside.

3. The vehicle body structure according to claim 2,

the front and rear surfaces of the enlarged terminal portion have a substantially triangular shape divided by the inclined surface, the groove wall portion, and the cab floor portion.

4. The vehicle body structure according to claim 3,

the enlarged terminal portion is arranged to form a closed cross section having a substantially parallelogram shape in cross section together with the inclined surface, the front and rear surfaces, the groove wall portion, and the panel main body portion.

5. The vehicle body structure according to claim 4,

the enlarged terminal end portion includes a bifurcated surface disposed so as to be sandwiched between the inclined surface and the front and rear surfaces at an inner end portion in the vehicle width direction.

6. The vehicle body structure according to claim 4,

the enlarged terminal portion is disposed so as to straddle a portion where the panel main body portion and the cab floor portion are continuous.

7. The vehicle body structure according to claim 1,

the tunnel is constituted by the lower dash panel and a member having a tunnel shape.

8. The vehicle body structure according to claim 1,

the cross member is composed of a plurality of members divided in the vehicle width direction,

the plurality of members are joined to form 1 member.

9. The vehicle body structure according to claim 1,

the cross member includes a joint extension portion extending along the side frame at a portion of the lower dash panel that overlaps with the side frame in the plate thickness direction.

10. The vehicle body structure according to claim 7,

the joint portion of the lower dash panel and the member having the tunnel shape is set to overlap the joint portion of the cross member and the tunnel.