JP6066104B2 - Vehicle panel structure - Google Patents

Description

  The present invention relates to a vehicle panel structure, and more particularly, to a vehicle panel structure having a predetermined panel member.

Generally, a vehicle panel structure such as a floor panel, a bonnet, a trunk lid, or a roof panel is used for a vehicle. Conventionally, techniques for reducing such vibrations of the vehicle panel structure and improving rigidity have been developed.
For example, in Patent Document 1, as a technique for reducing vibration, a floor panel is formed with a low-rigidity portion and a high-rigidity portion, a damping material is provided on the low-rigidity portion, and a floor panel is provided from an engine or the like via a frame member. A structure is disclosed in which the vibration transmitted to the vehicle is attenuated, thereby reducing the vibration of the floor panel and lowering the level of sound radiation into the vehicle interior.
As a technique for improving the rigidity, for example, in Patent Document 2, a face plate portion FRP (fiber reinforced plastic) is bonded and bonded to a lattice frame of a floor, and the reinforcing fiber of the FRP is provided to extend in a direction of ± 45 degrees. Thus, increasing the in-plane shear strength of FRP is disclosed.

JP 2004-217122 A JP 2014-4888 A

However, in the invention of Patent Document 1, although vibrations transmitted from the engine or the like through the frame member can be reduced, for example, external noise transmitted from the lower side of the floor panel through the space ( For example, there is a problem that noise such as tire noise and engine noise cannot be effectively insulated. Moreover, in the invention of Patent Document 2, although the rigidity of the floor can be increased, the above-described external noise cannot be sound-insulated.
Here, in general, noise transmitted from the lower side of the vehicle to the vehicle interior is blocked by a floor panel or a floor mat. However, in recent years, from the viewpoint of reducing the weight of the vehicle, there has been a tendency to make the floor panel and the floor mat thinner, which may reduce the sound insulation effect of noise. Therefore, when sound insulation is performed by a floor panel or the like, there is a problem that it is difficult to achieve both sound insulation properties and light weight.
By the way, in order to improve the aerodynamic characteristics of the vehicle, a floor under cover may be provided below the floor panel. Such a floor undercover is used as a current plate, and its effect is not sufficient because noise insulation is not the main purpose.

  The present invention has been made to solve the above-described problems of the prior art, and provides a vehicle panel structure capable of effectively achieving both sound insulation and weight reduction of noise transmitted from the outside. With the goal.

In order to achieve the above object, the present invention provides a vehicle panel structure, comprising: a predetermined panel member provided in a vehicle; and a surface of the predetermined panel member facing a space side where noise is transmitted. An attenuation panel member extending so as to cover at least a portion and having at least two of the outer peripheral edge portions connected to predetermined portions of the vehicle body, and the attenuation panel member has predetermined rigidity and predetermined thickness. It is composed of a panel-like viscoelastic member and a material having rigidity higher than that of this viscoelastic member, and both ends are fixed to at least two positions of the outer peripheral edge of the damping panel member connected to the vehicle body. The damping panel member has a high rigidity member embedded in the viscoelastic member so as to extend in a shape, and the damping panel member is caused by noise transmitted from the space due to a difference in rigidity between the high rigidity member and the viscoelastic member. And wherein the attenuating the membrane vibration of the raised attenuation panel member.
In the present invention configured as described above, the attenuation panel member is a predetermined panel member (for example, a floor panel, a bonnet, a trunk lid, a roof panel, or the like). Since it extends so as to cover a part and at least two of its outer peripheral edges are connected to the vehicle body (for example, a frame member), it is excited by noise transmitted from the space (for example, noise such as tire noise or engine noise). The membrane vibration of the damped panel member can be damped by the dissipation of strain generated in the viscoelastic member due to the difference in rigidity between the high-rigidity member and the viscoelastic member of the damping panel member. As a result, noise transmitted from the space to the predetermined panel member can be insulated. More specifically, when the damping panel member vibrates due to noise, a large strain energy is locally generated in the viscoelastic members around the high rigidity member due to the difference in rigidity between the high rigidity member and the viscoelastic member. By converting a part of this strain energy into thermal energy and effectively reducing the total vibration energy, the noise emission from the attenuation panel member to the predetermined panel member side is suppressed, thereby reducing the noise. Sound insulation is possible.
Further, according to the present invention, since an effective sound insulation effect can be obtained with a single attenuation panel member, it is possible to reduce the weight while securing a sufficient sound insulation effect by thinning a predetermined panel member. Furthermore, since the attenuation panel member according to the present invention is made of a panel-like viscoelastic member (for example, resin or aluminum material) having a predetermined rigidity and a predetermined thickness and a linear high-rigidity member, the attenuation panel member is provided. However, there is no significant increase in weight. Therefore, according to the present invention, it is possible to effectively achieve both noise insulation and weight reduction.

In the present invention, preferably, the high-rigidity member of the damping panel member is disposed away from each of both surfaces of the panel-like viscoelastic member.
In the present invention configured as described above, since the high-rigidity member is disposed away from each of both surfaces of the viscoelastic member, large distortion is locally generated in the upper and lower portions of the viscoelastic member around the high-rigidity member in the thickness direction. Can be effectively generated, and the vibration damping effect can be improved.

In the present invention, preferably, the high-rigidity member of the attenuation panel member is disposed at an intermediate position in the thickness direction of the panel-like viscoelastic member.
In the present invention configured as described above, since the high-rigidity member is disposed at the middle position in the thickness direction of the viscoelastic member, a large strain is locally applied to the upper and lower portions in the thickness direction of the viscoelastic member around the high-rigidity member. It can be generated more effectively.

In the present invention, preferably, the high-rigidity member of the damping panel member is made of a bundle of carbon fibers.
In the present invention configured as described above, since the high-rigidity member is composed of carbon fiber that is lightweight but highly rigid, noise insulation and weight reduction can be appropriately realized.

In the present invention, the attenuation panel member preferably has a rectangular outer peripheral edge portion, and the four corners of the rectangle are connected to the vehicle body.
In the present invention configured as described above, the attenuation panel member is connected to the vehicle body at the four corners of the rectangle forming the attenuation panel member. Therefore, the attenuation panel is more than the case where the attenuation panel member is connected to the vehicle body at the rectangular side or the like. The member is likely to vibrate, and a large distortion is likely to occur in the damping panel member, thereby increasing the vibration damping function.

In the present invention, preferably, two high-rigidity members of the attenuation panel member are provided in the attenuation panel member along two diagonal lines of the rectangle.
In the present invention configured as described above, since the pair of high-rigidity members are arranged along the diagonal line of the rectangle, the high-rigidity member exists so as to extend over the entire attenuation panel member, and is attenuated by the high-rigidity member. Since the region in which is applied becomes wide, the damping function can be effectively exhibited for many vibration modes caused by noise. For example, when a pair of high-rigidity members are arranged along the diagonal line of the attenuation panel member (that is, when arranged in an X shape) as in the present invention, an intermediate point between two opposing sides of the attenuation panel member is connected. Compared with the case where a pair of high-rigidity members are arranged along the line segment (that is, in the case of a cross-arrangement), the X-shaped arrangement is longer than the cross-shaped arrangement, so the attenuation by the high-rigidity member As a result, the region in which is applied becomes wider, and vibrations in more vibration modes can be damped.

In the present invention, preferably, the damping panel member further includes a connecting member configured to be wound around the high-rigidity member and connected to the vehicle body, and the high-rigidity member of the damping panel member includes: It is wound around the connecting member of the attenuation panel member and stretched in an annular shape.
In the present invention configured as described above, the high-rigidity member is wound around the connecting member and stretched in an annular shape, that is, the high-rigidity member is provided with a tight tension applied thereto. Is reinforced, and membrane deformation (out-of-plane deformation) of the attenuation panel member can be suppressed. In this case, since the attenuation panel member is reinforced by the linear high-rigidity member, film deformation of the attenuation panel member can be suppressed with little increase in weight.

In this invention, Preferably, it has a tension | tensile_strength provision structure which provides tension | tensile_strength to a highly rigid member, when connecting the connection member of an attenuation | damping panel member to a vehicle body further.
In the present invention configured as described above, since the tension is applied to the high-rigidity member when the coupling member of the attenuation panel member is coupled to the vehicle body using the tension applying structure, the attenuation panel member is further added by the high-rigidity member. It can reinforce and it becomes possible to suppress effectively the membrane deformation of an attenuation panel member.

In the present invention, preferably, the vehicle body has a plurality of frame members arranged in the vehicle body longitudinal direction and the vehicle width direction, and the predetermined panel member is a floor panel connected to these frame members, and the damping The panel member is provided below the floor panel so as to cover the floor panel.
In the present invention configured as described above, since the attenuation panel member provided below the floor panel is used so as to cover the floor panel, noise transmitted from below the floor panel (for example, tire noise, engine sound, etc.) Can be properly sound-insulated.

In the present invention, the attenuation panel member is preferably configured to be connected to the frame member.
In the present invention configured as described above, the damping panel member is connected to the frame member having high rigidity, and both ends of the high rigidity member are fixed to the frame member, so that the movement of the high rigidity member within the viscoelastic member is prevented. It can be limited appropriately. Therefore, effective distortion can be generated in the viscoelastic member, and the vibration damping effect can be improved.

  According to the vehicle panel structure of the present invention, it is possible to effectively achieve both insulation and weight reduction of noise transmitted from the outside.

It is the bottom view which looked at the floor panel and frame member of the vehicle body to which the panel structure for vehicles by the embodiment of the present invention is applied from the vehicle body lower part. 2A is the floor panel shown in FIG. 1, and FIG. 2B is an exploded perspective view showing the attenuation panel member used in the vehicle panel structure according to the embodiment of the present invention. 3A is a perspective view of the attenuation panel member according to the present embodiment, and FIG. 3B is a cross-sectional view taken along line BB in FIG. 3A. (C) is sectional drawing seen along CC line of FIG. 3 (A). It is a top view which shows the fiber member and pulley-like member in the attenuation | damping panel member by this embodiment. It is a side view of the pulley-shaped member in the attenuation | damping panel member by this embodiment. It is side surface sectional drawing of the pulley-shaped member in the attenuation | damping panel member by this embodiment. It is a bottom view which shows the example which applied the some attenuation | damping panel member in the panel structure for vehicles by embodiment of this invention to the floor panel of the vehicle body. It is sectional drawing of the panel structure for vehicles by embodiment of this invention seen along the VIII-VIII line of FIG. It is a side view which shows the example of attachment to the frame member of the attenuation | damping panel member by this embodiment. It is a side view which shows the example which attached the two attenuation | damping panel members of the vehicle body front-back direction by this embodiment to the frame member in the same location. It is side surface sectional drawing which shows an example of the tension | tensile_strength provision structure to the attenuation | damping panel member by this embodiment. It is a fragmentary sectional view of the attenuation panel member seen along the BB line of Drawing 3 (A) for explaining the attenuation effect of the attenuation panel member in the panel structure for vehicles by the embodiment of the present invention. It is a perspective view of the attenuation panel member for demonstrating the difference in the effect | action of the attenuation effect with respect to the direction of the fiber member of the attenuation panel member in the panel structure for vehicles by embodiment of this invention. It is a perspective view of an attenuation panel member for explaining an example (Drawing 14 (A)-(C)) of a vibration mode which arises in an attenuation panel member by an embodiment of the present invention, and the effect.

  Hereinafter, a vehicle panel structure according to an embodiment of the present invention will be described with reference to the accompanying drawings. Below, the example which applied the vehicle panel structure by embodiment of this invention to the floor panel of a vehicle body is demonstrated.

  First, with reference to FIG.1 and FIG.2, the whole structure of the vehicle panel structure by embodiment of this invention is demonstrated. FIG. 2 is a bottom view of a vehicle body floor panel and a vehicle body frame member to which a vehicle panel structure according to an embodiment of the present invention is applied, as viewed from below the vehicle body, and FIG. 2 is a floor panel shown in FIG. And FIG. 2B is an exploded perspective view (FIG. 2B) showing an attenuation panel member used in the vehicle panel structure according to the embodiment of the present invention. 1 and 2, the arrow W indicates the vehicle width direction, and the arrow L indicates the vehicle body longitudinal direction (the same applies to other drawings).

  FIG. 1 is a view of a monocoque body in an automobile as a vehicle as viewed from below, and only the main parts are shown with the fine parts omitted. In FIG. 1, reference numeral 1 denotes a floor panel, reference numeral 2 denotes a rear panel, reference numeral 3 denotes a pair of left and right front side frames, and reference numeral 4 denotes a pair of left and right rear side frames.

  First, as shown in FIG. 1, a pair of left and right side sills 10 extending in the longitudinal direction of the vehicle body are joined to both edges of the floor panel 1 in the vehicle width direction. A first floor frame 11 and a second floor frame 12 extending in the longitudinal direction of the vehicle body are joined to the lower surface of the floor panel 1.

  Next, as shown in FIG. 2A, the floor panel 1 is formed with a tunnel portion 13 that extends in the front-rear direction and bulges upward in the center in the vehicle width direction. A central cross member 14 extending in the vehicle width direction having a U-shaped cross section is joined to the upper surface of the floor panel 1 at a substantially middle portion in the longitudinal direction of the vehicle body. The central cross member 14 connects the tunnel portion 13 and the side sill 10 (see FIG. 1).

Next, as shown in FIG. 1, the second floor frame 12 is provided in the vicinity of the tunnel portion 3, and the first floor frame 11 is disposed between the second floor frame 12 and the side sill 10. .
Torque boxes 15 are formed at the left and right front ends of the floor panel 1. The torque box 15 is connected to the rear end portion of the front side frame 3 and to the front end portions of the side sill 10 and the first floor frame 11. In the vicinity of the front end portion of the first floor frame 11 and the second floor frame 12, the floor frames 11 and 12 are connected to each other by a short front cross member 16 joined to the lower surface of the floor panel 1. The first floor frame 11 is formed so as to be positioned on an extension line that is substantially rearward of the front side frame 3 in the longitudinal direction of the vehicle body.

  Next, the front end of the rear side frame 4 is connected to the rear end of the side sill 10. Further, the rear end portion of the side sill 10 and the rear end portion of the tunnel portion 13 are connected by a rear cross member 17 joined to the lower surface of the floor panel 1. The rear ends of the floor frames 11 and 12 are connected to the rear cross member 17.

  Here, in FIG. 1, the code | symbol T1-T8 and the code | symbol T11-T18 have shown the attachment part or attachment part candidate of the attenuation | damping panel member (19a-19d) mentioned later. The positions of the right mounting parts T1 to T8 and the left mounting parts T11 to T18 as viewed from the front of the vehicle are determined so as to be symmetrical. Attachment portions T1, T4, T7, T11, T14, and T17 are attachment portions to the side sill 10. In the following description, when it is not necessary to distinguish the attachment part, the attachment part is simply indicated by a symbol “T”.

  In the present embodiment, these attachment portions T are attachment positions to the side sill 10 as the strength member (rigid member), the floor frames 11 and 12, and the cross members 14, 16, and 17. In particular, in a plan view of the floor panel 1 as viewed from above, as the attachment portion T, an intersection (that is, a corner) between the strength member extending in the front-rear direction and the strength member extending in the vehicle width direction has an attachment strength. preferable.

Next, in FIG. 2 (B), it is arranged below the floor panel 1 and attached to the floor panel 1 via the frame members 10, 11, 12, 14, and 17 described above. A total of four damping panel members 19a-19d are shown. As shown in FIG. 2 (B), the damping panel members 19a to 19d have fiber members 21a1, 21a2, 21b1, 21b2, 21c1, 21c2, 21d1, 21d2 as high rigidity members in the viscoelastic member 20, respectively. Is embedded.
In addition, in the following description, when it is not necessary to distinguish each attenuation panel member 19a-19d, an attenuation panel member is only shown with code | symbol "19". Further, when it is not necessary to distinguish the fiber members 21a1, 21a2, 21b1,..., The fiber members are simply indicated by the reference numeral “21”.

  Next, the attenuation panel member according to the present embodiment will be described in detail with reference to FIGS. 3A is a perspective view of the attenuation panel member according to the present embodiment, and FIG. 3B is a cross-sectional view taken along line BB in FIG. 3A. C) is a cross-sectional view taken along line CC in FIG. 3A, and FIG. 4 is a plan view showing a fiber member and a pulley-like member in the attenuation panel member according to the present embodiment. FIG. 5 is a side view of the pulley-like member in the damping panel member according to the present embodiment, and FIG. 6 is a side sectional view of the pulley-like member in the damping panel member according to the present embodiment.

  As shown in FIG. 3A, the attenuation panel member 19 according to the present embodiment is embedded in the rectangular panel-like viscoelastic member 20 and the viscoelastic member 20, and extends in the in-plane direction of the viscoelastic member 20. An annular fiber member 21 extending (see also FIG. 3 (B)), and a pulley-like member 22 (FIG. 3 (C)) having a pulley shape, arranged at the four corners of the rectangle and wound around the end of the fiber member 21 Reference). The attenuation panel member 19 is provided with two fiber members 21 and four pulley-like members 22. In FIG. 3A, in order to clearly show the fiber member 21, the fiber member 21 embedded in the viscoelastic member 20 is shown by a solid line and is shown in a so-called see-through state. The pulley-like member 22 is also indicated by a solid line.

These fiber members 21 are made of fibers having higher rigidity than the viscoelastic member 20. Specifically, the fiber member 21 is a carbon fiber (particularly a long-fiber carbon fiber) bundled in a string shape, and as shown in FIGS. 3A and 4, the two pulley-like members 22. And is formed in an annular shape so as to be stretched between the two pulley members 22.
The viscoelastic member 20 is made of a material having a lower rigidity than that of the fiber member 21, for example, resin or aluminum. Incidentally, the strength of carbon fiber is about 10 times that of iron, and the rigidity of carbon fiber is about 7 times that of iron. The embedding of the fiber member 21 in the viscoelastic member 20 is realized, for example, by integrally molding the viscoelastic member 20 and the fiber member 21. Preferably, the fiber member 21 is disposed at an intermediate position in the thickness direction of the viscoelastic member 20 (see FIG. 3B).
The fiber member 21 may be composed of carbon fiber as a main component (for example, carbon fiber impregnated with synthetic resin) or a metal wire such as a piano wire (a plurality of twisted metal wires). Or an appropriate high-rigidity material such as glass fiber can be used.

  Next, as shown in FIGS. 5 and 6, the pulley-like member 22 has a kind of pulley shape (in other words, a bobbin shape), and an attachment hole 22 a is formed at the center. The pulley-like member 22 has a pair of flange portions 22b in the axial direction of the mounting hole 22a, and has a guide groove surface 22c that is recessed in a substantially semicircular cross section between the pair of flange portions 22b. The guide groove 22c is circular with the attachment hole 22a as the center. And the fiber member 21 is wound between a pair of pulley-like members 22 (the guide groove 22c).

  The fiber member 21 wound between the pair of pulley-like members 22 causes the first connecting line portion 21x and the second connecting line portion 21y extending between the pair of pulley-like members 22 to extend in parallel as shown in FIG. Is configured. And when adjusting the space | interval of a pair of pulley-shaped member 22 so that the tension | tensile_strength tensioned by each of these connection line parts 21x and 21y may be given, the tension | tensile_strength is mutually equal and the fiber member 21 is stretched. (In other words, it will be stretched). The fiber member 21 is embedded in the viscoelastic member 20 together with the pulley-like member 22 in a state of being stretched by the pulley-like member 22 in this way.

  Referring to FIG. 3A again, two fiber members 21 are provided on the attenuation panel member 19, and these two fiber members 21 are along two diagonal lines of the rectangle forming the attenuation panel member 19. Thus, each both ends are wound around the pulley-like member 22 provided in two corners located on the diagonal of this rectangle. That is, the pair of fiber members 21 are arranged so as to intersect so as to form a rectangular diagonal line of the attenuation panel member 19, that is, to form an X shape.

  Next, an example of the arrangement of the attenuation panel member according to the present embodiment will be described with reference to FIGS. FIG. 7 is a bottom view showing an example in which a plurality of attenuation panel members (a total of four attenuation panel members 19a to 19d shown in FIG. 2B) in the vehicle panel structure according to the embodiment of the present invention are applied to a floor panel of a vehicle body. FIG. 8 is a cross-sectional view of the vehicle panel structure according to the embodiment of the present invention viewed along the line VIII-VIII in FIG. 7, and is a front view in which an attenuation panel member 19 is provided below the floor panel. It is sectional drawing. In FIG. 8, the attenuation panel member 19 is shown in a side view.

As shown in FIG. 7, the attenuation panel member 19a is disposed on the front right side, the attenuation panel member 19b is disposed on the front left side, the attenuation panel member 19c is disposed on the rear right side, and the attenuation panel member 19d is disposed on the rear left side. It is arranged. In this case, the attenuation panel member 19a is attached at the attachment portions T1, T3, T4, and T6, the attenuation panel member 19b is attached at the attachment portions T11, T13, T14, and T16, and the attachment portion T4 is attached at the attenuation panel member 19c. , T6, T7, and T8, and the attenuation panel member 19d is attached at the attachment portions T14, T16, T17, and T18.
The attenuation panel member 19 is actually attached to the attachment portion T of the floor panel 1 using the attachment hole 22a of the pulley-like member 22 described above. In FIG. 7, for the sake of convenience of explanation, the pulley-like member 22 is denoted by a symbol “T”.

  As shown in FIG. 8, the attenuation panel member 19 (19a to 19d) is disposed below the floor panel 1 or the like, and is positioned at the lowermost part of the vehicle body. Such a damping panel member 19 functions as a current plate by covering the bottom surface of the floor panel 1 and contributes to improving the aerodynamic characteristics of the vehicle. Therefore, the attenuation panel member 19 functions in the same manner as a general floor undercover.

It should be noted that the attenuation panel member 19a and the attenuation panel member 19c adjacent in the longitudinal direction of the vehicle body may be integrally formed, that is, the attenuation panel member 19a and the attenuation panel member 19c may be integrated without being separated. . Further, the attenuation panel member 19b and the attenuation panel member 19d adjacent to each other in the longitudinal direction of the vehicle body may be integrally formed, that is, the attenuation panel member 19b and the attenuation panel member 19d may be integrated without being separated. .
Further, in the arrangement example shown in FIG. 7, the attenuation panel member 19 is not disposed below the tunnel portion 13 (see also FIG. 8), but the attenuation panel member 19 may be disposed below the tunnel portion 13. Good. In that case, one attenuation panel member 19 may be attached at the attachment sites T3, T13, T6, T16, and the other attenuation panel member 19 may be attached at the attachment sites T6, T16, T8, T18.

  Next, with reference to FIG.9 and FIG.10, the attachment example of the attenuation | damping panel member by this embodiment is demonstrated. FIG. 9 is a side view showing an example of attachment of the attenuation panel member to the frame member according to the present embodiment, and FIG. 10 shows that two attenuation panel members in the longitudinal direction of the vehicle body according to the embodiment are attached to the frame member at the same location. It is a side view showing an example.

  In FIG. 9, the pulley-like member 22 around which one end of the fiber member 21 in the attenuation panel member 19 is wound is attached to the side sill 10 by a bolt 25 as a screw member inserted through the attachment hole 22 a. An example is shown in which the pulley-like member 22 having the other end wound thereon is attached to the second floor frame 12 by a bolt 26 (see also FIG. 8). Of course, the side sill 10 and the floor frame 12 are formed with screw holes into which the bolts 25 or 26 are screwed, for example, by nut members fixed thereto by welding or the like. Since the attachment position to the side sill 10 is slightly inclined, as shown in FIG. 9, the upper surface (attachment surface to the side sill 10) of the one pulley-like member 22 is slightly inclined.

FIG. 10 shows a case where two pulley-like members 22 are attached to the same portion of the second floor 12. That is, one bolt 27 is screwed into the second floor frame 12 (the screw hole thereof) in a state where the mounting holes 22a of the pulley-like member 22 of the two different attenuation panel members 19 are inserted. The mounting example shown in FIG. 10 is applied to a mounting part T6 to which the attenuation panel member 19a and the attenuation panel member 19c are attached, and an attachment part T16 to which the attenuation panel member 19b and the attenuation panel member 19d are attached (see FIG. 7). .
Two pulley-like members 22 may be attached to the same portion of the side sill 10. Specifically, the two pulley-like members 22 may be attached to the attachment part T4 to which the attenuation panel member 19a and the attenuation panel member 19c are attached and the attachment part T14 to which the attenuation panel member 19b and the attenuation panel member 19d are attached ( (See FIG. 7).

  Next, referring to FIG. 11, a tension applying structure (mechanism) that applies a desired tension (in other words, tensile force) to the internal fiber member when the damping panel member according to the present embodiment is attached to the floor panel. explain. FIG. 11 is a side sectional view showing an example of a structure for applying tension to the attenuation panel member according to the present embodiment.

  FIG. 11 shows a structure in which tension is applied to the fiber member 21 in the attenuation panel member 19 by effectively using the bolt 41 and the nut 42 for attaching the attenuation panel member 19 as they are. Specifically, the pulley-like member 22 around which one end of the fiber member 21 in the attenuation panel member 19 is wound is attached to, for example, the second floor frame 12, and the pulley-like member 22 around which the other end of the fiber member 21 is wound is attached to the side sill. 10 shows the case of attaching to 10. In FIG. 11, a bolt 41 serving as a mounting screw member is fixed to the second floor frame 12 in advance in a state where the bolt 41 is inclined in the arrangement direction of the attenuation panel member 19. The pulley-like member 22 is integrated with a guide tube portion 23 into which the bolt 41 is slidably inserted.

  When the nut 42 screwed into the bolt 41 is tightened in a state where the guide cylinder portion 23 and the pulley-like member 22 are inserted into the bolt 41, the bolt 41 is inclined, so that the pulley shape into which the bolt 41 is inserted is inserted. The member 22 is gradually displaced in a direction away from the side sill 10, and this provides tension to the fiber member 21 in the attenuation panel member 19.

  The attachment manner on the side sill 10 side is the same as the attachment manner on the second floor frame 12 side. That is, by tightening the nut 44 screwed into the bolt 42, the pulley-like member 22 into which the bolt 42 is inserted is displaced in a direction away from the second floor frame 12, and this is moved into the damping panel member 19. Tension is applied to the fiber member 21.

  When tension is applied to the fiber member 21 as described above, the attenuation panel member 19 is further reinforced by the fiber member 21, and membrane deformation (out-of-plane deformation) of the attenuation panel member 19 can be effectively suppressed. .

In addition, as shown in FIG. 11, the tension applying structure is applied to both the pulley-like member 22 in which one end of the fiber member 21 in the attenuation panel member 19 is fixed and the pulley-like member 22 in which the other end is fixed. There is no particular limitation, and the tension applying structure as described above may be applied only to the pulley-like member 22 to which one end of the fiber member 21 is fixed.
The tension applying structure for applying tension to the fiber member 21 of the attenuation panel member 19 is not limited to that shown in FIG. 11, and the fiber member 21 is attached to the attenuation panel member 19 when the attenuation panel member 19 is attached to the floor panel 1. Various other structures may be applied as long as tension can be applied to the structure. Moreover, after attaching the attenuation | damping panel member 19 to the floor panel 1, you may apply the structure which provides tension | tensile_strength with respect to the fiber member 21. FIG.

  Next, the effect of the vehicle panel structure according to the embodiment of the present invention will be described.

  First, with reference to FIG. 12, the distortion which arises in the inside at the time of the vibration of the attenuation | damping panel member by embodiment of this invention is demonstrated. FIG. 12 is a partial cross-sectional view of the attenuation panel member taken along line BB in FIG. 3A for explaining the attenuation effect of the attenuation panel member in the vehicle panel structure according to the embodiment of the present invention. is there.

  As indicated by an arrow A1 in FIG. 12, since the fiber member 21 is highly rigid when the damping panel member 19 vibrates, the fiber member 21 hardly deforms (is not bent) during vibration. The strain concentrates on the elastic member 20. On the other hand, when the fiber member 21 is not embedded in the viscoelastic member 20, distortion occurs almost uniformly in the viscoelastic member 20. Therefore, in the configuration in which the fiber member 21 is embedded in the viscoelastic member 20 as in the present embodiment, the fiber is not affected when the damping panel member 19 vibrates as compared with the configuration in which the fiber member 21 is not embedded in the viscoelastic member 20. A large strain locally occurs in the viscoelastic member 20 around the member 21.

Here, the damping panel member 19 located at the lowermost part of the vehicle vibrates due to noise (for example, tire noise or engine sound) transmitted from below the vehicle. Thus, when the damping panel member 19 vibrates, As shown in FIG. 12, a large distortion occurs in the viscoelastic member 20 of the damping panel member 19.
Normally, vibration energy input to a certain member is converted into strain energy and kinetic energy. This strain energy is temporarily stored inside the member, and immediately after that, converted again into kinetic energy. The member vibrates. At this time, a part of the strain energy is converted into heat energy and dissipated.
As described above, when a large strain occurs in the viscoelastic member 20 of the damping panel member 19 due to the membrane vibration, the strain energy is large, so that the amount of energy converted into thermal energy in the vibration energy increases, that is, heat The amount of energy dissipated as energy increases. Therefore, the total vibration energy in the damping panel member 19 is considerably reduced, and the vibration is greatly attenuated.
Therefore, according to the attenuation panel member 19 according to the present embodiment, the vibration of the attenuation panel member 19 due to noise is attenuated, the vibration level is reduced, and the emission of noise from the attenuation panel member 19 to the floor panel 1 side is suppressed. That is, noise can be insulated.

As described above, according to the present embodiment, due to the large strain of the viscoelastic member 20 caused by the rigidity difference between the viscoelastic member 20 and the fiber member 21 generated when the damping panel member 19 undergoes membrane vibration, By greatly attenuating the membrane vibration, the vibration level can be reduced and noise can be appropriately insulated. Since the sound can be insulated by the attenuation panel member 19 in this way, a great sound insulation effect can be obtained by combining with the sound insulation function by the conventional floor panel 1 or floor mat. In addition, according to the attenuation panel member 19 according to the present embodiment, a great sound insulation effect can be obtained by the attenuation panel member 19 alone. Therefore, even if the floor panel 1 or the floor mat is thinned and lightened, a sufficient sound insulation effect is ensured. The Therefore, according to this embodiment, it is possible to achieve both weight reduction and sound insulation.
Here, since the attenuation panel member 19 according to the present embodiment is made of a relatively lightweight resin, carbon fiber, or the like, even if the attenuation panel member 19 is separately provided, the weight reduction of the vehicle is not hindered. Therefore, by using the attenuation panel member 19 together with the floor panel 1 and the floor mat reduced in weight as described above, it is possible to appropriately achieve both weight reduction and sound insulation.
Furthermore, since the attenuation panel member 19 according to the present embodiment also has a function as a floor undercover as a conventional current plate, it is only necessary to modify the conventional floor undercover, and it is necessary to separately provide a member having only a sound insulation function. Absent. That is, according to this embodiment, the sound insulation function can be appropriately realized by using the conventional floor undercover. In other words, the aerodynamic characteristics of the vehicle can be improved by using the attenuation panel member 19 having a sound insulation function.

  Depending on the material, there are materials that easily convert strain energy into thermal energy (for example, resin) and materials (such as iron) that strain energy is difficult to convert into thermal energy (such as strain energy to heat energy). The ease of conversion is expressed as a loss factor). In the present embodiment, a material in which strain energy is easily converted into thermal energy, that is, a material having a relatively large loss coefficient, is applied to the viscoelastic member 20 of the damping panel member 19 in order to obtain the above-described effects. And

  Next, with reference to FIG. 13, the conditions under which attenuation functions in the attenuation panel member according to the present embodiment will be described. FIG. 13 is a perspective view of the attenuation panel member for explaining the difference in the effect of the attenuation effect on the direction of the fiber member of the attenuation panel member in the vehicle panel structure according to the embodiment of the present invention. In FIG. 13, as in FIG. 3, the fiber member 21 in the attenuation panel member 19 is shown in a transparent state.

As for the vibration that causes deformation along the length direction of the fiber member 21 in the attenuation panel member 19 as indicated by an arrow B1 in FIG. 13, the high-rigidity fiber member 21 functions as a reinforcement that resists this vibration. Vibration is difficult to occur. For this reason, since the distortion hardly occurs in the viscoelastic member 20 of the attenuation panel member 19, the attenuation does not function so much in the attenuation panel member 19.
On the other hand, with respect to vibration that causes deformation perpendicular to the length direction of the fiber member 21 in the attenuation panel member 19 as indicated by an arrow B2 in FIG. 13, the fiber member 21 is reinforced to resist this vibration. Hardly work as. For this reason, the damping panel member 19 vibrates and a large distortion is generated in the viscoelastic member 20 of the damping panel member 19 (see FIG. 12).

  As described above, the damping panel member 19 according to the present embodiment has a small damping effect on the vibration along the length direction of the fiber member 21, but has a large damping effect on the vibration orthogonal to the length direction of the fiber member 21.

  Next, taking into account the conditions for the damping function of the damping panel member described in FIG. 13, a vibration mode in which the damping panel member according to the present embodiment can be damped will be described with reference to FIG. FIG. 14 is a perspective view of an attenuation panel member for explaining an example of vibration modes (FIGS. 14A to 14C) generated in the attenuation panel member according to the embodiment of the present invention and a difference in the effect thereof.

FIGS. 14A to 14C each show an example of a vibration mode due to membrane vibration of the attenuation panel member 19 when sound passes through the attenuation panel member 19. 14A shows an example of a low-order vibration mode (low-frequency vibration mode), FIG. 14C shows an example of a high-order vibration mode (high-frequency vibration mode), and FIG. (B) shows an example of an intermediate vibration mode.
14A to 14C, the state of the original attenuation panel member 19 is indicated by a solid line, and the state of the attenuation panel member 19 during vibration is indicated by a broken line. Further, the damping panel member 19 is shown in a simplified manner (specifically, the fiber member 21 is represented by a solid line, and the pulley-like member 22 is not shown).

  In the vibration modes shown in FIGS. 14A and 14C, as shown by arrows C <b> 1 and C <b> 2, vibration perpendicular to the length direction of the fiber member 21 in the attenuation panel member 19 occurs. Therefore, in these vibration modes, the damping function by the damping panel member 19 is exhibited. On the other hand, in the vibration mode shown in FIG. 14B, vibration mainly occurs along the length direction of the fiber member 21 in the attenuation panel member 19, that is, vibration orthogonal to the length direction of the fiber member 21. Does not occur. Therefore, in this vibration mode, the damping function by the damping panel member 19 is not so much exhibited.

  As described above, the damping panel member 19 according to the present embodiment has a vibration mode in which the damping function is not sufficiently exhibited as shown in FIG. 14B. However, the damping panel member 19 is resistant to many vibration modes caused by noise from below the vehicle. Thus, the damping function can be exhibited (that is, the damping function can be exhibited for various vibration modes other than the vibration modes shown in FIGS. 14A and 14C). This is because the pair of fiber members 21 are arranged along the diagonal line of the attenuation panel member 19, so that the fiber members 21 extend over the entire attenuation panel member 19, and the attenuation by the fiber members 21 acts. This is because the area is wide. For example, a case where a pair of fiber members 21 are arranged along the diagonal line of the attenuation panel member 19 as in the present embodiment (that is, an X-shaped arrangement), and an intermediate between two opposing sides of the attenuation panel member 19. Compared with the case where a pair of fiber members 21 are arranged along a line connecting points (that is, when arranged in a cross), since the length of the fiber member 21 is longer in the X-shaped arrangement than in the cross arrangement, the fiber member The region where the damping by 21 is applied becomes wide, and it is possible to appropriately cope with various vibration modes.

Here, since the longer fiber member 21 is better, it may be considered that the amount of the fiber member 21 applied to the attenuation panel member 19 should be increased. However, this makes the attenuation panel member 19 highly rigid. Because of the high rigidity, it is difficult for the membrane to vibrate, and the viscoelastic member 20 of the damping panel member 19 is less likely to be distorted and the damping function is reduced. In the case of high rigidity, the low frequency vibration mode does not occur, but the high frequency vibration mode still occurs. The high-rigidity damping panel member 19 cannot cope with such a high-frequency vibration mode appropriately because the damping function is small.
On the other hand, in this embodiment, a pair of string-like fiber members 21 are arranged in an X shape on the attenuation panel member 19 without increasing the amount of the fiber member 21 applied to the attenuation panel member 19 (see FIG. 3). As a result, more vibration modes are generated than the above-described high-rigidity damping panel member 19 (and low-frequency vibration modes that did not occur with high rigidity also occur), but membrane vibration is likely to occur, and the viscoelasticity of the attenuation panel member 19 is increased. Since the member 20 is likely to be greatly distorted and the damping function is increased, it is possible to appropriately cope with many vibration modes.

  Moreover, in this embodiment, the edge part of the fiber member 21 of the attenuation | damping panel member 19 is being fixed, Specifically, the both ends of the fiber member 21 are wound around the pulley-shaped member 22, and this pulley-shaped member 22 is passed through The attenuation panel member 19 is attached to a frame member such as the floor frame 12, and both ends of the fiber member 21 are fixed. In this way, compared with a case where both ends of the fiber member 21 are not fixed (for example, a case where both ends of the reinforcing fiber are not fixed as in the technique described in Patent Document 2), a large damping effect is obtained. Specifically, when both ends of the fiber member 21 are not fixed, the fiber member 21 moves in a direction in which distortion is less likely to occur in the viscoelastic member 20, and the distortion of the viscoelastic member 20 tends to be small. When both ends of the fiber member 21 are fixed, the movement of the fiber member 21 in the viscoelastic member 20 is restricted, and a large distortion occurs in the viscoelastic member 20, so that a large damping effect is obtained.

  Below, the further modification of embodiment of this invention is demonstrated.

  In the embodiment described above, the fiber member 21 is disposed at the middle position in the thickness direction of the viscoelastic member 20, but the fiber member 21 is appropriately offset in the vertical direction from the middle position in the thickness direction of the viscoelastic member 20. May be arranged, or the fiber member 21 may be arranged so that a part of the viscoelastic member 20 is exposed.

  In the above-described embodiment, the corners of the attenuation panel member 19 are connected to the frame member such as the floor frame 12. However, at least two locations on the outer peripheral edge of the attenuation panel member 19 may be connected to the frame member. For example, the sides of the attenuation panel member 19 may be connected to the frame member. In one example, the four sides of the attenuation panel member 19 may be connected to the frame member, that is, the entire outer peripheral edge of the attenuation panel member 19 may be connected to the frame member. Even in this case, if the fiber member 21 having the same configuration as that of the above-described embodiment is applied to the attenuation panel member 19, the same effect as that of the above-described embodiment can be obtained. However, when the four sides of the attenuation panel member 19 are connected to the frame member, the attenuation panel member 19 is less susceptible to membrane vibration than when the four corners of the attenuation panel member 19 are connected to the frame member. Therefore, the attenuation effect by the attenuation panel member 19 is reduced.

  In the above-described embodiment, the rectangular attenuation panel member 19 is shown, but various shapes may be applied to the attenuation panel member 19. For example, the attenuation panel member 19 may be formed in a circle, an ellipse, or a polygon such as a triangle, pentagon, or hexagon. Even in the attenuation panel member 19 having such various shapes, the fiber member 21 is embedded in the viscoelastic member 20, and at least two places on the outer peripheral edge of the attenuation panel member 19 are connected to the frame member. 21 may be fixed. Preferably, in the polygonal damping panel member 19, the corners of the polygon are connected to the frame member.

In the embodiment described above, the pulley-like member 22 having a pulley shape is shown as the connecting member according to the present invention, but the use of such a pulley-like member 22 is not limited. As long as the fiber member 21 can be fixed and the attenuation panel member 19 can be connected to the frame member, connecting members having various forms may be applied. For example, a connecting member having a substantially cylindrical shape may be applied.
In still another example, the attenuation panel member 19 may be connected to the frame member by bonding (for example, adhesive bonding) without using the connecting member as described above. Even in that case, the fiber member 21 may be fixed at the joining portion.

In the above-described embodiment, the example in which the predetermined panel member according to the present invention is applied to the floor panel 1 has been shown. However, the predetermined panel member according to the present invention is applied to a bonnet, a roof panel, a door panel, a trunk lid, and the like. May be. Even when such a panel member is used, the attenuation panel member 19 may be disposed so as to cover at least a part of the surface of the panel member facing the space where noise is transmitted. Specifically, when a bonnet, a roof panel, or the like is used as the predetermined panel member, the attenuation panel member 19 is disposed on the vehicle inner side than the predetermined panel member. Therefore, the “surface facing the space where noise is transmitted” in the present invention includes not only the surface facing the vehicle outside in the predetermined panel member but also the surface facing the vehicle inner side in the predetermined panel member.
When a bonnet or the like is used as the predetermined panel member, the attenuation panel member 19 may be provided without using the frame member. In that case, the attenuation panel member 19 may be disposed at an appropriate location in the vehicle body.

DESCRIPTION OF SYMBOLS 1 Floor panel 10 Side sill 11 1st floor frame 12 2nd floor frame 13 Tunnel part 14 Center cross member 19 Damping panel member 20 Viscoelastic member 21 Fiber member (high rigidity member)
22 Pulley-like member

Claims (10)

A vehicle panel structure,
A predetermined panel member provided in the vehicle;
In this predetermined panel member, the damping panel member extends so as to cover at least a part of the surface facing the space side where noise is transmitted, and at least two of the outer peripheral edge portions thereof are connected to predetermined positions of the vehicle body, Have
The attenuation panel member is composed of a panel-like viscoelastic member having a predetermined rigidity and a predetermined thickness, and a material having a rigidity higher than the rigidity of the viscoelastic member, and is connected to the vehicle body. A high-rigidity member embedded in the viscoelastic member so that both ends are fixed and extend linearly at least at two locations on the outer peripheral edge of the member. A vehicle panel structure characterized by attenuating a membrane vibration of a damping panel member excited by noise transmitted from the space due to a difference in rigidity from an elastic member.   The vehicular panel structure according to claim 1, wherein the high-rigidity member of the attenuation panel member is disposed apart from each of both surfaces of the panel-like viscoelastic member.   The vehicle panel structure according to claim 2, wherein the highly rigid member of the attenuation panel member is disposed at an intermediate position in the thickness direction of the panel-like viscoelastic member.   The vehicular panel structure according to any one of claims 1 to 3, wherein the high-rigidity member of the attenuation panel member is formed of a bundle of carbon fibers.   5. The vehicle panel structure according to claim 1, wherein an outer peripheral edge portion of the attenuation panel member is formed in a rectangular shape, and four corners of the rectangular shape are connected to the vehicle body.   The vehicle panel structure according to claim 5, wherein two high-rigidity members of the attenuation panel member are provided in the attenuation panel member so as to be along two diagonal lines of the rectangle. Further, the damping panel member has a connecting member configured to be wound around the high-rigidity member and connected to the vehicle body,
The vehicle panel structure according to any one of claims 1 to 6, wherein the high-rigidity member of the attenuation panel member is wound around a connecting member of the attenuation panel member and stretched in an annular shape.   The vehicle panel structure according to claim 7, further comprising a tension applying structure that applies tension to the high-rigidity member when the connecting member of the attenuation panel member is connected to the vehicle body. The vehicle body has a plurality of frame members arranged in the vehicle body longitudinal direction and the vehicle width direction,
The predetermined panel member is a floor panel connected to these frame members,
The vehicle panel structure according to claim 1, wherein the attenuation panel member is provided below the floor panel so as to cover the floor panel.   The vehicle panel structure according to claim 9, wherein the attenuation panel member is configured to be coupled to the frame member.

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