JPH0628431Y2 - Fuel tank sound deadening structure - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Object of the Invention] (Field of Industrial Application) The present invention relates to a sound deadening structure for a fuel tank mounted on a vehicle.

(Prior Art) A conventional sound deadening structure for a fuel tank is, for example, Jikken Sho 5
There is one similar to that of JP-A-4-22807 as shown in FIG. 17 and FIG. That is, in this structure, the baffle plate 103 made of a mesh plate is vertically installed in the fuel tank 101 made of a mesh plate. A flange 105 is provided on the upper edge of the baffle plate 103, and the flange 105 is joined to the upper wall surface 107 in the fuel tank 101 by spot welding or the like. The baffle plate 103 regulates the movement of the fuel in the front-rear direction when the vehicle starts, brakes, and the like, so as to prevent a collision noise on the inner wall surface of the fuel tank 101.

(Problems to be solved by the invention) By the way, when the baffle plate 103 having high rigidity receives the moving force of the fuel as described above, a large load is intensively applied to the welded portion between the flange 105 and the upper wall surface 107. Becomes Therefore, in order to prevent the occurrence of cracks in the fuel tank 101 due to such a concentrated load, it is not possible to reduce the plate thickness of the fuel tank 101 beyond a certain level, and a reinforcing material is required, which limits weight reduction. there were.

On the other hand, it has been conventionally known that a baffle plate is integrally molded with a resin fuel tank to reduce the weight.

However, the amount of protrusion of the baffle plate is generally large, and since it is a thin plate shape, when blow molding is performed, the resin does not sufficiently enter the root of the baffle plate,
The amount of extension of the resin may become too large. As a result, there is a problem that a predetermined plate-shaped baffle plate cannot be obtained, the molding thickness is likely to be non-uniform, and the thickness management becomes difficult.

In any case, as described above, the baffle plate 10
In the case where 3 is hung from the upper wall surface 107, it is generated by the collision with the upper wall surface 107 of the fuel in the vicinity of the full fuel tank.
This is caused by the so-called noise suppression and a wave rising to the liquid surface due to the rapid movement of fuel collides with the upper wall surface 107. It did not directly contribute to the so-called suppression of pica sounds.

Particularly in recent years, in four-wheel drive vehicles, there is a tendency to arrange a fuel tank on the lower surface of the floor panel of the rear seat due to its structure, and the fuel tank is thinner and has a larger cross-section seat.
Therefore, it becomes easier for the pica sound and the doson sound to be generated on the upper wall surface, and the need for countermeasures against them is great.

Further, since the baffle plate 103 itself is also hard and has a flat surface, it causes a picic noise due to fuel collision. For this reason, the actual situation is that the desired silencing effect cannot be obtained with any of the structures.

On the other hand, it is also known that a resin baffle plate is bonded to the upper wall surface of the fuel tank, and some effects are obtained.

However, even the baffle plate mounted in this way is not sufficient for silencing the pica sound because the waves rising on the liquid surface collide with the flat surface. Also, since the sound of dead sound is also muted by utilizing the elasticity of the baffle plate itself, the baffle plate itself must be made thick to some extent, but considering the internal volume of the fuel tank, it cannot be made that thick, and the sound of the dead sound is muffled. The effect had to be insufficient.

Further, since the baffle plate is adhered to the upper wall surface, the degree of freedom in its mounting is low, and if a flat baffle plate is bent and adhered to the corners of the upper wall surface, it may peel off due to the elastic restoring force of the baffle plate. is there. Further, there is a problem that it is difficult to mount a baffle plate or the like having a roughened surface and a small bonding area.

Therefore, the present invention can easily mount even a baffle plate having a difficult shape such as adhesion, expands the degree of freedom of the mounting form, and more effectively muffles pica and doson to the inner wall surface of the fuel tank. The purpose of the present invention is to provide a sound deadening structure for a fuel tank.

[Means for Solving the Problem] (Means for Solving the Problems) In order to achieve the above object, a muffling structure for a fuel tank of the present invention has a resin baffle having a constant thickness and a large number of open surface voids. A sound deadening structure for a fuel tank, in which a plate is attached along an inner wall surface of a fuel tank, wherein a mounting plate piece having a projecting joint portion is provided so as to surround the edges of the baffle plate across the front and back sides. The joining piece portion is fixed to the inner wall surface of the fuel tank.

(Operation) In the muffler structure of the fuel tank configured as described above, the joint plate portion of the mounting plate portion having the joint piece portion is fixed to the inner wall surface of the fuel tank by penetrating the baffle plate. The surface of the baffle plate is supported with respect to the inner wall surface of the fuel tank, and the baffle plate can be easily attached along the inner wall surface of the fuel tank. When the fuel tries to collide with the inner wall surface of the fuel tank by its movement, the fuel first collides with the resin baffle plate. Then, when the surface of the baffle plate is covered with fuel, air is confined in a large number of voids which the baffle plate has between the wall surface and the wall surface, so that the collision force of the fuel can be alleviated and so-called noise can be prevented. When a wave or the like rising on the wall surface collides with the baffle plate, it is dispersed and extinguished by a large number of open voids in the surface of the baffle plate, and so-called picic noise can be suppressed.

(Embodiment) An embodiment of the present invention will be described below.

1 to 8 relate to the first embodiment of the present invention, and FIG. 1 shows the fuel tank II shown in FIG. 3, for example.
FIG. 2 is a sectional view taken along a line arrow, and FIG. 2 is a perspective view seen from the same plane. The fuel tank 1 is made of, for example, a steel plate, and is constructed by welding the upper shell 3 and the lower shell 5 to each other. The fuel tank 1 is provided, for example, on the lower surface of the floor panel in the rear seat of a four-wheel drive vehicle, and the fuel tank 1 as a whole is thin and has a large cross-sectional area.

The upper shell 3 has a shape corresponding to a seat, and has a wide range upper wall surface 7 that is gradually inclined forward and upward. A baffle plate 9 is attached to the inner wall surface of the fuel tank 1, for example, the upper wall surface 7 of the upper shell 3.

The attachment of the baffle plate 9 is performed by using the attachment plate pieces shown in FIGS. 4 and 5, for example.
The baffle plate 9 itself has a shape as shown in FIG.

That is, the baffle plate 9 is made of a resin wire 13 in a mesh shape, and each resin wire 13 is formed in a wavy shape. When viewed from the direction A in FIG. 6, as shown in FIGS. 7 and 8. It has a surface wave shape in which downward ridge lines of the mountains appear at regular intervals, and when viewed from the direction of arrow B in the figure, the resin wire rods 13 are in a state of being substantially uniform in thickness. A void 15 is formed between the resin wire rods 13. Therefore, the baffle plate 13 has a constant thickness and has a large number of voids 15 whose surface is open. The void density of the baffle plate 13,
The thickness can be appropriately selected.

The fixing of the baffle plate 9 to the upper wall surface 7 is performed by the mounting plate piece 11 as shown in FIGS.
By the front and rear edges shown in FIG. The mounting plate piece 11 is made of, for example, a steel plate, has a substantially U-shaped cross section that surrounds the edge 9a of the baffle plate 9 across the front and back, and is formed along the entire edge 9a of the baffle plate 9 to form a retainer. It is supposed to function as. The front surface side 17 of the mounting plate piece 11 is formed longer than the back surface side 19 thereof as shown in FIG. 4, and joint piece portions 21 are projectingly provided on the back surface side 19 at both ends in the longitudinal direction and joined to the front surface side. Through hole 23 through which the piece 21 penetrates
Are formed.

On the other hand, on both sides of the edge portion 9a of the baffle plate 9, two engaging holes 25a and 25b are provided in the protruding direction of the joining piece portion 21 of the mounting plate piece 11.
5a and 25b are baffle plates 9 in this embodiment
Then, it is not specially provided, but the void 15 is used as it is. Then, the joint piece portion 21 penetrates the back surface 9a of the baffle plate 9 through the first locking hole 25a and the front surface 9c through the second locking hole 25b, and the upper wall surface 7 of the fuel tank 1 is spot welded. It is fixed by etc.

Next, attachment of the baffle plate 9 will be described.

The mounting plate piece 17 is first subassembled to the baffle plate 9. That is, the mounting plate piece 11 in a state as shown in FIG. 4 before mounting is fitted into the edge portion 9a of the baffle plate 9, and the edge portion 9a is arranged so as to cover the front and back sides.

Next, the joining piece portion 21 is deformed, and first the first locking hole 25a is made to penetrate from the back surface 9b of the baffle plate 9 and the through hole 23 of the mounting plate piece 11 is made to penetrate,
Connect the connecting piece 21 to the baffle plate 9 as shown on the left side of the figure.
To the surface 9c side. Next, the tip end side of the joining piece portion 21 is further bent, and it is projected toward the back surface 9b side of the baffle plate 9 so as to penetrate the second locking hole 25b.
Constitutes the plane portion of the joining piece portion 21. Therefore, the attachment plate piece 11 is attached along the front and rear edges 9a of the baffle plate 9, and the retainer function of the attachment plate piece 11 holds the shape of the baffle plate 9.

Then, when the upper shell 3 is joined to the lower shell 5, the upper wall surface 7 of the upper shell 3 is arranged so that the back surface 9b of the baffle plate 9 faces each other, and the tip of each joining piece portion 21 of each mounting plate piece 11 is attached to the upper shell 7. It is fixed to the shell 3 by spot welding or the like. In this mounted state, spot welding of the mounting plate piece 11 to the upper shell 3 is performed by the flat upper wall surface 7, and the edge portion 9a of the baffle plate 9 can be positioned as close as possible to the corner portion 1a.

After the mounting, the mounting plate piece 11 exerts a retainer function and retains the shape of the baffle plate 9, so that the baffle plate 9 is extremely unlikely to hang down and is prevented from interfering with, for example, the float of the fuel gauge.

Before joining the upper shell 3 by spot welding, the joining piece portion 21 was bent so as to penetrate the second locking hole 25b as shown by the solid line in FIG. By welding, as a result, it may be configured as shown by the solid line in the figure.

In this way, the surface of the baffle plate 9 is uneven, and the adhesion area is small.
Although it is difficult to mount it on the mounting plate 11, it can be mounted very easily by the mounting plate piece 11. Moreover, according to the mounting plate piece 11 as described above,
Although the edge portion 9a of the baffle plate 9 can be reliably supported with respect to the upper wall surface 7, the welding portion is performed only on one side of the joining piece portion 21, so that the number of welding points is small and the mounting work is performed. Becomes extremely easy. Since the mounting plate piece 11 is sub-assembled to the baffle plate 9 to be assembled as described above, the shape of the baffle plate 9 can be maintained in advance, the handling at the time of assembling is easy, and the assembling work is extremely simple.

Next, the operation will be described.

For example, as shown in FIG. 1, when a wave rises on the liquid surface of the fuel as shown in FIG. 7 due to normal vehicle start and liquid movement at the time of braking near full fuel, on the upper wall surface 7 of the upper shell 3. The waves that are about to collide first collide with the baffle plate 9. Then, when the waves collide with the baffle plate 9, they are dispersed by the voids 15 formed between the resin wire rods 13 as shown by the arrows in the figure, and disappear. Therefore, the picking sound on the upper wall surface 7 due to the wave is suppressed. The baffle plate 9 has a surface wavy shape, a mesh shape, and the resin wire 13
Because of irregularity, the wave-dissipating effect is higher, and the effect of suppressing picic sounds is high.

When the fuel collides with the upper wall surface 7 due to the movement of the fuel at the time of starting or braking of the vehicle, the fuel first collides with the baffle plate 9, so that the air in the gap 15 formed between the resin wire rods 13 of the baffle plate. Are confined between the upper wall surface 7 and the upper wall surface 7 as shown in FIG. Therefore, the impact force that acts on the upper wall surface 7 is mitigated by the confined air, and the thud sound can be suppressed.

Further, in such a baffle plate 9, since the air to be enclosed is made large as shown in FIG. 8, the void 15 exists even if a certain thickness is secured. Therefore, when the tank is full, the fuel enters the void 15. It is possible to suppress the decrease in the volume in the fuel tank 1 as much as possible. Since the baffle plate 9 has a resin mesh shape, the baffle plate 9 can be made lighter in weight for its thickness. Since the surface of the baffle plate 9 is not flat, it is possible to prevent the generation of picic noise due to the collision of waves with the baffle plate 9 itself as in the conventional case. When the fuel collides with the baffle plate 9, the load is received by the upper shell 3 via the enclosed air, so that a large load is not concentrated on the welded portion of the mounting plate piece 11. Therefore, the plate thickness of the fuel tank 1 and the mounting plate piece 11 can be made as thin as possible, and this contributes to the weight reduction of the fuel tank 1 in combination with the baffle plate 9 having a resin mesh shape. Since a large load is not concentratedly applied to the welding point, the mounting plate piece 11 is not limited to a steel plate, and can be made of a resin plate, which can further reduce the weight. In this case, each foot of the mounting plate piece is fixed to the fuel tank 1 made of steel plate by heat sealing or adhesion.

FIG. 9 shows a modified example of the baffle plate. The baffle plate 27 has, for example, a large number of resin needle materials 31 protruding from the surface of a resin base material 29 and has a constant thickness. A large number of surface-released voids 33 are provided between the needle-making materials 31. Baffle plate 2
The length and the implantation density of the resin needle material 31 of No. 7 can be appropriately selected.

In this baffle plate 27, the resin base material 29 side faces the upper wall surface 7, and the resin needle material 31 side faces the lower liquid surface side. The upper wall surface 7 of such a baffle plate 27
The first locking hole 25a and the second locking hole 25b are specially provided in the baffle plate 27, though the fixing is performed in the same manner as described above. Also in this modified example, the drone sound and the pica sound can be suppressed as shown in FIGS. 10 and 11, and at that time, the resin needle material 31 is flexed to some extent to exert a wave canceling action and the like. Enhances the effect of suppressing sound and picic sounds.

FIG. 12 shows still another modification of the baffle plate. The baffle plate 35 is constituted by a resin plate 37 on a line in a mesh shape, and the resin plate 37 stands in the thickness direction of the baffle plate 35. This ensures the thickness of the baffle plate 35 itself. Then, a large number of voids 39 are provided between the resin plates 37. The void density and thickness of the baffle plate 35 can be selected as appropriate.

In this modified example, like the baffle plate 9, a first through hole 2 is formed by utilizing the gap 39 without providing a special through hole.
5a and the second locking hole 25b, and the mounting plate piece 1
1 can be attached. Also in this example, it is possible to suppress the drone sound and the pica sound as shown in FIG. 13 and FIG.
5 is easy to manufacture.

In the above-described embodiment, as shown in FIG. 5, the mounting plate piece 11 has a shape that surrounds the edges of the baffle plate 9 over the front and back sides.
The corner portion 1a of the upper wall surface 7 can be arranged as close as possible to the corner portion 1a, and the fuel collision noise of the less rigid upper wall surface 7 can be effectively mitigated.

15 and 16 show a second embodiment of the present invention. In the second embodiment, the mounting plate piece 41 is not configured to have a retainer shape, but has a shape that locally supports the edge portion 9a of the baffle plate 9. Then, in the mounting plate piece 41, the joining piece portion 43 is integrally formed on the front surface side 45 of the mounting plate piece 41, and the mounting plate piece 41 has the back surface side 47 engaged with the back surface 9b of the baffle plate 9 so that the baffle plate 9 has a shape that surrounds the front and back. The joining piece portion 43 penetrates through the locking hole 49 of the baffle plate 9 and is fixed to the upper shell 3 by spot welding or the like.

The mounting plate piece 41 may be mounted by crimping the front surface side 45 and the back surface side 47 to the baffle plate 9.

The attachment of this embodiment is simply performed by bending the joining piece portion 43 so as to pass through the locking hole 49, and the attaching work is further simplified. After installation, the edge 9 of the baffle plate 9
It is possible to arrange “a” to the very end of the corner portion 1a of the fuel tank 1, and it is possible to mitigate the noise caused by the collision of the fuel with the corner portion 1a to some extent. Further, in this embodiment, the edge portion 9a of the baffle plate 9 is provided between the mounting plate pieces 41 and the corner portion 1a of the fuel tank 1 is provided.
If it is extended to (1), it is possible to prevent the picking noise and the thud noise at the corner portion 1a of the fuel tank 1.

The invention is not limited to the above embodiment. For example, the fuel tank is not limited to a steel plate, but can be a resin tank. In this case, the mounting plate piece can also be made of steel plate or resin, and the fuel of each foot of the mounting plate can be selected. The fixing to the inner wall surface of the tank can be performed by heat welding or adhesion. In addition, the baffle plate is not limited to be attached along the upper wall surface of the fuel tank so that the entire surface is in close contact, but it may be attached with some loosening. Furthermore, the baffle plate can be attached to a plurality of locations separately, and the attachment location is not limited to the upper wall surface, and can be attached to other wall surfaces. For example, when the baffle plate is attached to the corner portion of the wall surface of the fuel tank 1, it is possible to suppress the thud sound when the fuel collides with the corner portion due to the movement of the fuel, and the adhesive does not easily peel off.

[Effect of the Invention] As is clear from the above, according to the configuration of the present invention, the wave of fuel can be canceled by the large number of voids in the baffle plate, so that the picic noise caused by the collision of the wave with the wall surface can be eliminated. Can be suppressed. When the fuel collides with the wall surface due to the movement of the fuel, the air in many voids of the baffle plate is confined to exert an elastic force, the impact force acting on the wall surface is alleviated, and the thud sound can be suppressed. . Since the baffle plate has a large number of surface-opened voids, the surface is not flat, and it is possible to suppress the generation of picic noise due to the collision of waves with the surface of the baffle plate. Since the baffle plate has a large number of voids, the baffle plate suppresses the pitch noise and the dounce noise, so that it is possible to suppress the decrease in the volume in the fuel tank even if a certain thickness is secured. Even if the fuel collides with the baffle plate, a large load is not concentrated on the fixed portion of the mounting plate piece with respect to the wall surface, and the fuel tank and the mounting plate piece can be made thin and lightweight. . The baffle plate has an uneven surface and a small bonding area, and even if the baffle plate has a shape that is difficult to bond or heat-bond to the wall surface in the fuel tank, it can be easily mounted by the mounting plate piece. The baffle plate can be installed with some degree of slack, and the degree of freedom in its installation is wide.

Further, the baffle plate can be arranged up to the corner of the fuel tank to effectively muffle the fuel.

[Brief description of drawings]

FIG. 1 is a cross section of a fuel tank to which a silencing structure for a fuel tank according to a first embodiment of the present invention is applied, which is a cross sectional view taken along the line II of FIG. 3, and FIG. 2 is a perspective view seen from the same plane. 3 and 4 are perspective views of the fuel tank, FIG. 4 is an enlarged exploded perspective view of the same portion, FIG. 5 is an enlarged sectional view of the same portion, and FIG. 6 is a baffle plate used in the first embodiment. Fig. 7, Fig. 7 and Fig. 8 are explanatory views of the same action, Fig. 9 is an enlarged perspective view of a modified example of the baffle plate, Figs. 10 and 11 are explanatory views of the same action, and Fig. 12 is a baffle plate. FIG. 13 and FIG. 14 are enlarged perspective views of essential parts according to still another modified example of FIG.
FIG. 5 is an enlarged exploded perspective view of a main part according to the second embodiment, FIG. 16 is an enlarged sectional view of the same, and FIG. 17 is a vertical sectional view of a fuel tank to which a sound deadening structure for a fuel tank according to a conventional example is applied. The figure is a cross-sectional view of the same. 1 ... Fuel tank 7 ... Upper wall surface (inner wall surface) 9, 27, 35 ... Baffle plate 15, 33, 39 ... Void 11, 41 ... Mounting plate piece 21, 43 ... Joining piece portion 23 ... Through hole 25a ... first locking hole 25b ... second locking hole 49 ... locking hole

Claims (1)

[Scope of utility model registration request] 1. A sound deadening structure for a fuel tank, wherein a resin baffle plate having a constant thickness and having a large number of open-surfaced voids is attached along an inner wall surface of the fuel tank, and a joint piece portion is projected. A sound deadening structure for a fuel tank, characterized in that an edge portion of the baffle plate is surrounded by front and back sides by a mounting plate piece and the joint piece portion is fixed to an inner wall surface of the fuel tank.