JP4506695B2 - Body reinforcement structure - Google Patents

Description

  The present invention relates to a vehicle body reinforcement structure that reinforces a connecting portion between a dash panel and a vehicle body floor.

  In a vehicle, a cabin panel may vibrate and generate sound due to skeletal vibration. For this reason, as the vehicle body structure, for example, there is a structure in which each part of the cross member having a phase difference in the vibration mode at the time of floor resonance and the floor panel are connected by a connecting member having a tensile force to reduce the amplitude of both. Yes (see, for example, Patent Document 1).

However, in this conventional structure, if there is no portion that vibrates in the opposite phase in the basic structure excluding the connecting member, it is not possible to sufficiently cancel (cancel) the sound generation to the occupant accompanying the skeletal vibration.
Japanese Utility Model Publication No. 4-96588

  In view of the above facts, an object of the present invention is to provide a vehicle body reinforcement structure that can sufficiently cancel the sound generation to the occupant accompanying the skeletal vibration.

The vehicle body reinforcing structure according to the first aspect of the present invention includes a dash panel that separates an engine room and a cabin, a vehicle body floor that is connected to a lower side of the dash panel, and a connection between the dash panel and the vehicle body floor. A high-rigidity skeleton member disposed across the front and rear of the vehicle body, a high-rigidity member spaced apart from the skeleton member on the vehicle body upper side, the connecting portion side, and the high-rigidity member side. Connecting means for connecting and reinforcing the connecting portion, and the connecting means is arranged in a standing state with respect to the connecting surface of the connecting portion , and the dash panel and the vehicle body with respect to a specific frequency. It is characterized by being erected on a node that vibrates in the opposite phase with the floor .

According to the vehicle body reinforcing structure of the present invention described in claim 1, when vibration is input to the highly rigid skeleton member, the dash panel and the vehicle body floor also vibrate together with the skeleton member. Since the connecting means for connecting the two to the connecting surface is erected with respect to the connecting surface, the vibration phase between the dash panel and the vehicle body floor can be changed before and after the erected portion of the connecting means. Thus, that Do is possible to adjust the vibration characteristics of the vibration characteristics and the vehicle body floor of the dash panel. Here, since the connecting means is erected at a node portion that vibrates the dash panel and the vehicle body floor in opposite phases with respect to the specific frequency, when vibration of the specific frequency is input to the skeleton member, Air can be vibrated in opposite phases on the dash panel side and the vehicle body floor side, and sound generation for the occupant can be canceled.

  A vehicle body reinforcement structure according to a second aspect of the present invention is the vehicle body reinforcement structure according to the first aspect, wherein a reinforcement member extending in the vehicle width direction is disposed at the connecting portion, and the connecting means stands up corresponding to the reinforcement member. It was established.

  According to the vehicle body reinforcing structure of the present invention described in claim 2, since the connecting means is erected corresponding to the reinforcing member, when a load is transmitted between the skeleton member and the erected portion of the linking means. In addition, the transmission of the load is ensured, and the vibration phase between the dash panel and the vehicle body floor can be changed more reliably. Further, the deformation of the dash panel is suppressed by the reinforcing member.

According to a third aspect of the present invention, there is provided the vehicle body reinforcing structure according to the first or second aspect , wherein in the state in which vibration is transmitted to the connecting portion, the vibration transmitted to the connecting portion is connected to the connecting portion. The means is suppressed by an axial force.

According to the vehicle body reinforcing structure of the present invention described in claim 3 , when the vibration is transmitted to the connecting portion, the connecting means suppresses the vibration transmitted to the connecting portion by the axial force. Before and after, the vibration phase between the dash panel and the vehicle body floor can be changed.

As described above, according to the vehicle body reinforcement structure of the first aspect of the present invention , the connecting means is erected at the node that vibrates the dash panel and the vehicle body floor in opposite phases with respect to the specific frequency. Therefore, when vibration of a specific frequency is input to the skeletal member, the air in the passenger compartment is vibrated in opposite phases on the dash panel side and the vehicle body floor side, thereby sufficiently canceling the sound generation for the occupant accompanying the skeletal vibration It has an excellent effect of being able to.

  According to the vehicle body reinforcing structure of the second aspect, the vibration phase between the dash panel and the vehicle body floor can be more reliably ensured by the load transmission between the frame member and the standing portion of the connecting means by the reinforcing member. It has an excellent effect of being able to be changed.

According to the vehicle body reinforcing structure of the third aspect , the sound generation can be canceled by changing the vibration phase between the dash panel and the vehicle body floor before and after the erected portion of the connecting means by the axial force of the connecting means. It has an excellent effect.

[First Embodiment]
A first embodiment of a vehicle body reinforcing structure in the present invention will be described with reference to the drawings. In the figure, arrow UP indicates the upward direction of the vehicle, arrow FR indicates the forward direction of the vehicle, and arrow W indicates the width direction of the vehicle.

  As shown in the schematic diagram of FIG. 1, a dash panel 16 that separates the engine room 12 and the cabin 14 is disposed substantially vertically on the vehicle body 10. A vehicle body floor 18 constituting the floor surface of the cabin 14 is connected to the lower side of the dash panel 16 (a front floor portion of the vehicle body floor 18 is shown in FIG. 1). A floor tunnel portion 18A is formed in the vehicle width direction intermediate portion of the vehicle body floor 18 along the vehicle body longitudinal direction. The floor tunnel portion 18A has a cross-sectional shape viewed from the vehicle body longitudinal direction so that the opening portion extends downward from the vehicle body. It is in the shape of an approximate U.

  The connecting portion 20 (boundary region portion) between the dash panel 16 and the vehicle body floor 18 includes a first inflection portion 20A bent downward from the vehicle body rear side from the dash panel 16 disposed substantially vertically, and the vehicle body floor. 18 and a second inflection portion 20B bent upward from the vehicle body front side. The first inflection portion 20A and the second inflection portion 20B extend along the vehicle width direction. The connecting portion 20 is formed such that both the left and right sides of the floor tunnel portion 18A are inclined upward toward the front side of the vehicle body. The connecting surface 20C on the front side of the connecting portion 20 has a dash lower as a reinforcing member extending in the vehicle width direction. A pair of left and right cross members 32 are provided.

  The dash lower cross member 32 extends to the connecting surface 20C near the center in the vehicle width direction of the connecting portion 20, that is, to the vicinity of the upright portion 19 in the front portion of the floor tunnel portion 18A, and has a cross-sectional shape viewed from the vehicle width direction. The opening has a cross-sectional hat shape with the vehicle body facing downward. The dash lower cross member 32 is joined to the connecting portion 20 by welding or the like, thereby forming a closed cross-sectional structure extending in the vehicle width direction.

  A pair of left and right front side members 22 as high-rigidity skeleton members extend along the longitudinal direction of the vehicle body on both sides of the front portion of the vehicle body 10, and these front side members 22 are connected to the dash panel 16 and the vehicle body. The connecting portion 20 with the floor 18 is disposed across the vehicle body. Further, as shown in the schematic diagram of FIG. 3, a floor under reinforcement 23 extending along the vehicle body front-rear direction is connected to the rear end portion of the front side member 22.

  As shown in FIG. 1, the front side member 22 has a front side member front portion 22A disposed along the vehicle front-rear direction on both sides of the front portion of the vehicle body, and the vehicle body rearward downward in the vicinity of the dash panel 16. The kick-up portion 22B is bent and the front-side member rear portion 22C extends from the kick-up portion 22B to the vehicle rear side.

  The front side member front portion 22A has a closed cross-sectional structure constituted by a front side member outer and a front side member inner. Further, the kick-up portion 22B and the front side member rear portion 22C have a cross-sectional hat shape in which a cross-sectional shape viewed from the front-rear direction of the vehicle body has an opening portion directed upward of the vehicle body. A closed cross-section structure extending in the vehicle longitudinal direction is formed by joining the kick-up portion 22B and the connecting portion 20 and joining the front side member rear portion 22C and the vehicle body floor 18. In other words, the connecting part 20 is arranged along the kick-up part 22B, the vehicle body floor 18 is arranged along the front side member rear part 22C, and the side view shape from the connecting part 20 to the vehicle body floor 18 is The shape is in accordance with the side view shape (kick shape) from the kick-up portion 22B to the front side member rear portion 22C.

  The kick-up portion 22B connects the front side member front portion 22A and the front side member rear portion 22C that are offset in the vehicle body vertical direction, and the kick-up portion 22B and its front and rear portions, that is, the kick portion around the kick-up portion 22B. 22K (see FIG. 3) has higher rigidity than the other parts in order to ensure front collision performance.

  As shown in FIG. 1, in the vehicle body 10, an instrument panel reinforcement 24 as a high-rigidity member is disposed in an instrument panel (not shown) so as to be separated from the front side member 22 toward the upper side of the vehicle body. The instrument panel reinforcement 24 is a highly rigid pipe-shaped vehicle body structural member, extends along the vehicle width direction above the connecting portion 20, and has left and right mounting portions 25 (schematic in FIG. 2). (See the plan view).

  An instrument panel brace 26 as a connecting means is attached to an intermediate portion of the instrument panel reinforcement 24 in the vehicle width direction. The instrument panel brace 26 extends to the connecting part 20 side, and reinforces the connecting part 20 by connecting the connecting part 20 side and the instrument panel reinforcement 24 side. Here, the instrument panel lace 26 is fixed to the dash lower cross member 32, whereby the instrument panel lace 26 is connected to the connecting portion 20 via the dash lower cross member 32 (corresponding to the dash lower cross member 32). It arrange | positions in the state standing with respect to 20 C of connecting surfaces. In the present embodiment, the instrument panel brace 26 includes a first virtual surface 30A extending in the vehicle width direction connecting the first inflection part 20A and the instrument panel reinforcement 24, a second inflection part 20B, and the instrument panel reinforcement 24. The second virtual surface 30 </ b> B extending in the connecting vehicle width direction and the region surrounded by the connecting portion 20 are provided.

  The instrument panel brace 26 is a shaft-like member, and in a state where vibration is transmitted to the connecting portion 20, the vibration transmitted to the connecting portion 20 is suppressed by an axial force. For this reason, it is preferable that the axial direction (arrow X direction) of the instrument panel brace 26 is a vertical direction or a substantially vertical direction with respect to the connecting surface 20C. In the present embodiment, it is a substantially vertical direction. The instrument panel brace 26 has a dash panel 16 and a vehicle body floor 18 for a specific frequency (for example, a specific frequency up to a middle frequency range, a specific frequency within a range of 0 Hz to 400 Hz where solid propagation sound is likely to be generated). It is erected on a node 28 (see FIG. 4) that vibrates in the opposite phase.

(Action / Effect)
Next, the operation and effect of the above embodiment will be described.

  As shown in FIG. 3, when the load F is input to the front side member 22 in the vertical direction of the vehicle body, the kick portion 22K has high rigidity, so that a wide range of parts of the skeleton including the front side member 22 vibrate. To do. At this time, the mass of the vibrating part is large and the dash panel 16 and the vehicle body floor 18 also vibrate. However, as shown in FIG. 4, the vibration transmitted to the connecting portion 20 is suppressed by the axial force of the instrument panel brace 26. As a result, the surface vibration of the kick portion 22K is suppressed, and a skeletal mode in which the dash panel 16 and the vehicle body floor 18 vibrate in opposite phases (a mode in which the volume change of the passenger compartment sound field does not easily occur) is excited. That is, the vibration phase between the dash panel 16 and the vehicle body floor 18 is changed before and after the standing portion of the instrument panel brace 26 (with the tip of the instrument panel brace 26 as a fulcrum), so that the vibration characteristics of the dash panel 16 and the vehicle floor 18 The vibration characteristics can be adjusted. As a result, it is possible to cancel the sound generation, and the sound generation for the occupant accompanying the skeleton vibration can be sufficiently canceled with a small countermeasure mass.

  Here, when the load is transmitted between the front side member 22 and the standing portion of the instrument panel brace 26 shown in FIG. 1, the transmission of the load is ensured by the dash lower cross member 32, and the dash panel 16 The vibration phase with the vehicle body floor 18 can be changed more reliably. At this time, deformation of the dash panel 16 is suppressed by the dash lower cross member 32.

  The instrument panel brace 26 is erected on a node portion 28 (see FIG. 4) that vibrates the dash panel 16 and the vehicle body floor 18 in opposite phases with respect to a specific frequency. When input, the instrument panel brace 26 excites a skeletal mode in which the dash panel 16 and the vehicle body floor 18 are unlikely to generate sound that vibrates in opposite phases. As a result, the air in the vehicle interior vibrates in opposite phases on the dash panel 16 side and the vehicle body floor 18 side, so that sound generation for the occupant is sufficiently canceled and road noise can be reduced.

[Second Embodiment]
Next, a second embodiment of the vehicle body reinforcing structure will be described with reference to FIGS. The vehicle body reinforcement structure according to the second embodiment is characterized in that the standing position on the connecting portion 20 side in the instrument panel brace 26 is different, and the other configurations are substantially the same as those in the first embodiment. Therefore, the same reference numerals are given and the description is omitted.

  As shown in the schematic diagram of FIG. 5, the instrument panel brace 26 is erected with respect to the connecting surface 20C near the center in the vehicle width direction on the connecting portion 20 side, that is, the upright portion 19 in the front portion of the floor tunnel portion 18A. Has been.

  FIG. 6 shows a perspective view of the vehicle body 10 in the second embodiment. As shown in FIG. 6, a floor cross member 34 extending in the vehicle width direction is disposed on the vehicle body floor 18 in order to improve the strength of the vehicle body floor 18. The floor cross member 34 and the front side member 22 are joined together by welding or the like from the vertical direction of the vehicle body with the vehicle body floor 18 interposed therebetween. Further, a tunnel brace 36 is covered on the upper portion of the floor tunnel portion 18A in the vehicle body floor 18.

  A pair of left and right floor toe braces 38 extending downward toward the rear side of the vehicle body are fixed to the middle portion of the instrument panel reinforcement 24 near the center in the vehicle width direction by welding or the like. The lower end of the tip of the floor toe brace 38 is fixed to the tunnel brace 36 by a fixing means such as a bolt 39. Further, a cowl toe brace 40 is fixed to the instrument panel reinforcement 24 by welding or the like slightly outside the mounting portion of the floor toe brace 38 on the right side in the drawing. The cowl toe brace 40 extends toward the front upper side of the vehicle body, and is fixed to a cowl 42 disposed above the dash panel 16 by fixing means such as a bolt 41. The instrument panel reinforcement 24 is fixed to a bracket whose left and right ends are attached to the mounting portion 25 and is supported by a floor toe brace 38 and a cowl toe brace 40 to ensure rigidity in the vertical direction of the vehicle body.

  A high-rigidity mounting bracket (not shown) that extends downward is welded to the lower surface of the instrument panel reinforcement 24 slightly outside the mounting portion of the floor toe brace 38 on the left side in the drawing (left side in the drawing). The upper end portion of the instrument panel brace 26 is attached to the mounting bracket. The mounting bracket includes a mounting surface (not shown) as a surface including the vehicle longitudinal direction and the vehicle vertical direction, and a bolt insertion hole (not shown) penetrating the mounting surface in the vehicle width direction is formed. . A bolt insertion hole (not shown) is also formed through the upper end portion of the instrument panel brace 26, and the upper end portion of the general surface 26A of the instrument panel brace 26 overlaps the mounting surface of the mounting bracket from the outside in the vehicle width direction. At the same time, the bolt insertion holes are aligned with each other, and a bolt (not shown) is inserted and fastened, whereby the upper end portion of the instrument panel brace 26 is fixed to the mounting bracket.

  The instrument panel brace 26 is formed by bending a long and substantially rectangular iron plate material by press molding or the like, and is formed at the front and rear parts (the vehicle body front side part and the vehicle body rear side part in the assembled state) of the instrument panel brace 26. The reinforcing portions 26B are respectively formed. The reinforcing portion 26B includes flange portions that are bent at substantially right angles from the front end side and the rear end side of the general surface 26A and extend outward in the vehicle width direction, and further inside from these flange portions. There is a folded portion bent at a substantially right angle (in the direction in which the tip portions approach each other). In this way, by forming the reinforcing portions 26B at the front and rear portions of the instrument panel brace 26 and bending them in a substantially U shape, the rigidity of the instrument panel brace 26 is ensured, and even if a moment is generated in a vibration state, the instrument panel brace 26 is bent. The brace 26 is difficult to bend. For this reason, in a state where vibration is transmitted to the connecting portion 20, the instrument panel brace 26 can sufficiently suppress the vibration transmitted to the connecting portion 20 with an axial force.

  Further, the lower end portion of the general surface 26A of the instrument panel brace 26 is bent downward toward the outer side in the vehicle width direction to form a bolt insertion hole, and is arranged along the side portion 36A of the tunnel brace 36 to be a bolt 43. It is being fixed by fixing means, such as.

  Also in the second embodiment described above, it is possible to sufficiently cancel the sound generation for the occupant due to the skeleton vibration by the same action as the first embodiment.

[Supplementary explanation of the embodiment]
In FIG. 6, the arrangement state of the instrument panel brace 26 in the first embodiment is shown as an example of an instrument panel brace 26 indicated by a two-dot chain line.

  In the above embodiment, the connecting means is the instrument panel brace 26 formed by bending a plate material, but the connecting means is another connecting member having rigidity such as a rod-like member (for example, a connecting shaft) that functions as a connecting member. It may be a means.

  In the above embodiment, the instrument panel brace 26 as the connecting means is fixed to the dash lower cross member 32 or the tunnel brace 36 as the reinforcing member, but the connecting means is, for example, in the front part of the floor tunnel portion 18A. You may fix directly to the connection part 20, such as fixing directly to the upright part 19 without passing through another member.

  Further, in the above embodiment, the instrument panel brace 26 as the connecting means is fixed to the instrument panel reinforcement 24 as the high-rigidity member via the mounting bracket, but the connecting means is directly fixed to the instrument panel reinforcement 24, for example. Alternatively, it may be fixed to another high-rigidity member such as the steering support 44 or the floor toe brace 38 fixed to the instrument panel reinforcement 24. Even when the connecting means is fixed to another high-rigidity member, it is preferable that the axial direction of the connecting means is a vertical direction or a substantially vertical direction with respect to the connecting surface.

  Furthermore, in the above-described embodiment, the dash lower cross member 32 as the reinforcing member is disposed on the connecting surface 20C on the front side of the connecting portion 20, but the reinforcing member extending in the vehicle width direction is the back side of the connecting portion (below It may be arranged on the side). In this case, it is preferable that the connecting means be erected corresponding to the reinforcing member, that is, above the reinforcing member via the vehicle body floor.

It is a mimetic diagram showing the body reinforcement structure concerning a 1st embodiment of the present invention in a perspective view. It is a schematic diagram which shows the vehicle body reinforcement structure which concerns on the 1st Embodiment of this invention by planar view. It is a mimetic diagram showing a vehicle body reinforcement structure concerning a 1st embodiment of the present invention by a sectional view. It is a schematic diagram which shows the vibration generation state of the vehicle body reinforcement structure which concerns on the 1st Embodiment of this invention. It is a schematic diagram which shows the vehicle body reinforcement structure which concerns on the 2nd Embodiment of this invention with a perspective view. It is a perspective view which shows the vehicle body reinforcement structure which concerns on the 2nd Embodiment of this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 Car body 12 Engine room 14 Cabin 16 Dash panel 18 Car body floor 20 Connecting part 20C Connecting surface 22 Front side member (frame member)
24 Instrument panel reinforcement (high rigidity member)
26 Instrument panel brace (connection means)
28 Node 32 Dash Lower Cross Member (Reinforcement Member)

Claims (3)

A dash panel separating the engine room and the cabin;
A vehicle body floor connected to the lower side of the dash panel;
A high-rigidity skeleton member disposed across the vehicle body at the connecting portion between the dash panel and the vehicle body floor;
A highly rigid member that is spaced apart from the skeleton member above the vehicle body; and
Connecting means for connecting the connecting portion side and the high-rigidity member side to reinforce the connecting portion;
Have
The connecting means is arranged in a standing state with respect to the connecting surface in the connecting portion, and is set up in a node portion that vibrates the dash panel and the vehicle body floor in opposite phases with respect to a specific frequency. Car body reinforcement structure characterized by.   The vehicle body reinforcing structure according to claim 1, wherein a reinforcing member extending in a vehicle width direction is disposed at the connecting portion, and the connecting means is erected corresponding to the reinforcing member. 3. The vehicle body reinforcing structure according to claim 1, wherein in a state in which vibration is transmitted to the connecting portion, the connecting means suppresses the vibration transmitted to the connecting portion by an axial force.

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