JPH0364325B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a support structure for a fuel tank of an automobile or the like. More specifically, the present invention relates to a support structure for a fuel tank that supports the fuel tank at the bottom of a vehicle body constituted by a floor panel and a frame.

(Prior Art) A fuel tank of an automobile or the like is normally supported in a suspended state at the bottom of the vehicle body, which is constituted by a floor panel and a frame fixed to the panel. Such a suspension support structure for a fuel tank is described in Japanese Utility Model Application No. 192122/1983. The support structure described in this public law is as shown in Figure 5.
The tank 1 is held and supported by a band 2 extending under the tank 1, and both ends of the band 2 are fixed to a frame 4 fixed to a floor panel 3 with bolts, nuts, etc.

However, in the above support structure, both ends of the band 2 that supports the fuel tank 1 are fixed to the bottom frame 4 of the vehicle body, which has great rigidity and has almost no elasticity. The fuel tank is fixedly and inelastically supported on the bottom of the vehicle body, which is composed of a fuel tank, and therefore, there is a problem in that, for example, the vehicle body and the fuel tank resonate when the vehicle is running, and the vibrations of both are amplified.

In order to solve this problem, the inventor of the present invention considered a method of directly attaching both ends of the band to the floor panel 3. Since the floor panel 3 itself has great elasticity unlike the frame 4, the above method allows the fuel tank 1 to be elastically supported at the bottom of the vehicle body, thereby suppressing resonance between the vehicle body and the fuel tank 1 and reducing vibration. Although problems can be suppressed, on the other hand, the support of the fuel tank 1 becomes uncertain, and there is a problem that the fuel tank 1 may shift from the band 2 and fall in the event of a collision, for example.

(Objective of the Invention) In view of the object of the present invention and the above-mentioned circumstances, it is possible to suppress defects caused by vibration by elastically supporting a fuel tank, and at the same time, to avoid impairing the reliability of supporting the fuel tank. That is, it is an object of the present invention to provide a support structure for a fuel tank that does not cause the fuel tank to shift or fall during driving.

(Structure of the Invention) In order to achieve the above object, a support structure for a fuel tank according to the present invention includes a vehicle body constituted by a floor panel constituting the bottom surface of the vehicle body and a frame fixed to the bottom surface of the floor panel. In a fuel tank support structure that suspends and supports a fuel tank at the bottom, one side portion of the fuel tank is supported by a band that has one end attached to the floor panel and the other end attached to a component of the bottom of the vehicle body, The fuel tank is characterized in that the other side portion of the fuel tank is supported by bolting to the frame via an elastic material.

(Examples) Hereinafter, the present invention will be described in detail with reference to examples shown in the drawings.

FIG. 1 is a view of one embodiment of the fuel tank support structure according to the present invention, viewed from the underside of the vehicle body, and FIG.
It is a - line cross-sectional schematic diagram in a figure.

As shown in the figure, the fuel tank 1 is supported at the bottom of the vehicle body, which is constituted by a floor panel 3 forming the bottom surface of the vehicle body and a frame 4 fixed to the bottom surface of the panel 3. In the support structure according to the present invention, one half of the fuel tank 1 is supported by a band 2 whose end is directly attached to the floor panel 3, and the other half is attached to the frame 4 using an elastic material ( (not shown in FIGS. 1 and 2) and is supported by tightening with bolts 5.

In this embodiment, both ends of the metal band 2 are fixed to the floor panel 3, and the right half 1a of the fuel tank 1 is suspended and supported by the band 2 on the bottom of the vehicle body, and the remaining left half 1b is attached to the bolt 5. Therefore, it is suspended and supported on the bottom of the vehicle body by tightening it to the frame 4 via an elastic material 6 such as rubber (see FIG. 3, which will be explained below).

The material of the band 2 is not particularly limited, but it is preferably non-stretchable and has enough strength to support the fuel tank. One end 2a of the band 2 is wound around a pin 10, and the pin 10 is secured to a bracket 11 fixed to the floor panel 3, and the other end 2b is secured to a bracket 12 fixed to the floor panel 3 via a spacer 13 with a bolt. It is tightened and fixed with 14.

The left half 1b of the fuel tank is divided into a cross frame 4a extending in the lateral direction of the vehicle through a mounting flange 1c provided at the periphery of the tank, and a left frame 4b disposed on the left side of the vehicle and extending in the longitudinal direction of the vehicle. It is tightened using bolts 5 at three locations. This bolt tightening is carried out by interposing a rubber 6 between the frame 4 and the washer 15, as shown in FIG. 3, which is a sectional view taken along the line 1 in FIG. By burying the flange 1c, the flange 1c is held between the rubber 6, and the bolt 5 is inserted from the washer 15 side and screwed onto the nut member 16 fixed to the back side of the frame 4, and tightened while compressing the rubber 6. be. 17 is a spacer.

In FIG. 1, the direction of arrow F is the forward direction of the vehicle body, 4c is a right frame disposed on the right side of the vehicle body and extends in the longitudinal direction of the vehicle body, and 4d is a cross frame extending in the lateral direction of the vehicle body.

In the above embodiment, the right half 1a of the fuel tank 1 is elastically supported by the band 2, and the left half 1b is elastically supported by the bolt 5, but the parts supported by the band 2 and the bolt 5 are not necessarily the right half and the left half. It is not necessary to divide the fuel tank 1 into two parts, and support one side with the band 2 and the other side with the bolt 5. Furthermore, the direction of the band 2 does not necessarily have to be in the longitudinal direction of the vehicle body.

Both ends of the band 2 are attached to the floor panel 3, but it is sufficient that at least one end is attached to the floor panel 3, and the other end is attached to a component of the bottom of the vehicle body. Furthermore, attaching the end of the band 2 to the floor panel means attaching it directly to the floor panel 3 in order to elastically support the fuel tank by utilizing the elasticity of the floor panel 3. Any mounting mode is acceptable as long as it is capable of elastically supporting the fuel tank using elasticity, that is, the mounting section of the band can be displaced to some extent in the direction of arrow A in FIG. 2 based on the elasticity of the floor panel 3. good.

Of course, any bolt tightening via the elastic material 6 may be used as long as the flange 1c presses the elastic material 6 and can be displaced to some extent in the direction of arrow A.

Next, when we compare the vibration characteristics of the conventional inelastic support structure and the elastic support structure of the present invention in terms of the level of muffled sound in the vehicle interior, we find that the sound pressure of the conventional muffled sound is as shown in Figure 4. Level A is engine speed 700~
The sound pressure level b of the present invention reaches its peak at 800 rpm, that is, in the idle speed range, whereas the peak of the sound pressure level b of the muffled sound of the present invention occurs at engine speeds outside the idle speed range.
This allows the engine speed to be lower than 600 rpm.

In other words, by elastically supporting the tank, it is possible to change the phase of the vibration of the vehicle body and the vibration of the tank caused by this vibration, and as a result, the resonance point changes, and the vibration caused by the vibration of the vehicle body changes. It is possible to change the sound pressure level of muffled sounds.

(Effects of the Invention) As described above, in the support structure for a fuel tank according to the present invention, one side of the fuel tank is supported by a band having at least one end attached to the floor panel, and the other side of the fuel tank is supported by an elastic material. It is supported by bolting to the frame via the frame.

Therefore, one side of the fuel tank is elastically supported by a band using the large elasticity of the floor panel, and the other side is also attached to the non-elastic frame with bolts. In this case, since the elastic material is interposed, it is similarly supported elastically, and since the fuel tank can be supported as a whole under elastic force, it is similar to the fuel tank of the vehicle body. It is possible to suppress resonance and suppress problems caused by vibration.

In addition, although the fuel tank is supported elastically, the other side is securely bolted to the frame with sufficient rigidity, so the fuel tank support is highly reliable. There is no risk of the fuel tank shifting or falling.

[Brief explanation of drawings]

FIG. 1 is a bottom view of an embodiment of the fuel tank support structure according to the present invention as seen from the underside of the vehicle body, FIG. 2 is a schematic cross-sectional view taken along the line - in FIG. 4 is a diagram showing the relationship between the engine speed and the sound pressure level of the muffled sound inside the vehicle in the conventional inelastic support structure and the elastic support structure of the present invention, and FIG. 5 is the conventional support structure. It is a schematic diagram showing a structure. 1... Fuel tank, 2... Band, 3... Floor panel, 4... Frame, 5... Bolt.

Claims (1)

[Claims] 1. In a fuel tank support structure that suspends and supports a fuel tank on the bottom of a vehicle body, which is constituted by a floor panel constituting the bottom surface of the vehicle body and a frame fixed to the bottom surface of the floor panel, one side of the fuel tank One end of the fuel tank was attached to the floor panel and the other end was supported by a band attached to the component of the bottom of the vehicle body, and the other side of the fuel tank was supported by bolting to the frame via an elastic material. A fuel tank support structure characterized by: