JPS5815756A - Drawing construction of piping in fuel tank - Google Patents

Abstract

PURPOSE:To reduce a level of noise, by preventing and suppressing transmission of oscillation from a fuel pump mounting flange to a fuel tank. CONSTITUTION:Seven screw holes are drilled in a ring 2 welded to a fuel tank 1, and a metallic plate 3 and rubber made vibration absorbing member 4 are tightened by seven bolts 5. A fuel delivery pipe 6 and return pipe 7 are welded to a flange 8, and the flange 8 is mounted to the vibration absorbing member 4 by a wire-like stopper 9 not to cause a fuel leak. A fuel pump 10 is mounted to a breacket 11, and the bracket 11 is welded to the flange 8. Since the flange 8 is mounted to the fuel tank 1 through the vibration absorbing member 4, an elastic material, the fuel tank is not contacted to the flange with a metallic part, and transmission of vibration can be inhibited.

Description

DETAILED DESCRIPTION OF THE INVENTION This invention relates to a fuel tank piping extraction structure for assembling pressure and suppressing transmission to the tank.

Conventional. For example, this bridge has a structure in which a flange is made by welding piping to a metal disc and is fastened to the fuel tank with bolts via a rubber packing fx, or a fuel pump is installed inside the fuel tank.

A structure in which a fuel pump is attached to a flange is known.

However, the conventional one... The flange to which the piping was welded made metal contact with the fuel tank via a tightening bolt. As a result, the vibration of the fuel pump body. Vibrations caused by fluctuations in the suction pressure of the fuel pump caused the fuel tank to resonate through the flange, causing noise inside the vehicle cabin.

As measures to reduce suction pressure fluctuations in fuel pumps, the development of continuous suction type pumps instead of the conventional intermittent suction type, and the use of sag dampers to reduce pressure fluctuations are being considered. No measures have yet been taken that focus on the pipe outlet. Furthermore, the association has not yet taken measures to reduce vibration by incorporating the fuel pump into the fuel tank.

The present invention is characterized in that a vibration absorbing member is interposed between the flange and the fuel tank in order to avoid metal contact between the flange and the fuel tank, and vibration absorption from the vibration absorbing member prevents vibration transmission from the flange to the fuel tank. Obstruction. The purpose of this is to reduce the vibration of the fuel tank and the noise inside the vehicle as a result.

A first embodiment of the present invention will be explained with reference to FIGS. 1 and 2. FIG.

This is an example in which the fuel pump is installed inside the fuel tank. Figure 1 shows the external appearance of the fuel tank, and Figure 2
The figure shows details of the fuel pump and piping.

Seven screw holes are cut in a ring 2 welded to a fuel tank l, and a metal plate 8 and a vibration absorbing member 4 made of rubber are fastened with seven bolts 5.

A discharge vibro and a return vibrator 7 serving as fuel piping are welded to a flange 8, and the flange 8 is attached to the vibration absorbing member 4 by a wire-like stopper 9 so as to prevent fuel from leaking. The fuel pump 10 is attached to a bracket 11, and the bracket 11 is welded to the flange 8. Fuel is sucked in through the filter 12, and the fuel is pumped through the fuel pump l.
It passes through a discharge vibro and is sent to an engine (not shown). The operation of the above embodiment in which the fuel not used by the engine is returned to the fuel tank 1 through the return vibe 7 will be explained. fuel pump 10
vibrations and vibrations of the discharge vibro are transmitted to the flange 8, but since the flange 8 is attached to the fuel tank 1 via the vibration absorbing member 4, which is an elastic body, the metal between the fuel tank and the flange is transmitted to the flange 8. There is no contact and vibration transmission is prevented and suppressed. The vibration absorbing member 4 also acts as a seal around the bolt 5 to prevent fuel leakage.

Further, the whitening of the holding plate 8 having such a shape is to prevent the flange 8 from lifting when the internal pressure of the fuel tank 1 increases.

The protrusion 114m of the vibration absorbing member 4 serves to prevent the stopper 9 from slipping. The convex s8& of the flange 8 serves to prevent slippage between the vibration absorbing member 4 and the flange 8 when the internal pressure of the fuel tank 1 increases.

The contact portion 1a of the fuel tank 1 with the vibration absorbing member 4 and the contact portion 8a of the presser plate 3 with the vibration absorbing member 4 are finished in curved shapes so as not to damage the vibration absorbing member 4. In particular, when the internal pressure of the fuel tank 1 increases, shear stress is applied to the contact portion 8a of the holding plate 8 to the vibration absorbing member 4, so a particularly large curved surface is required.

Further, a clearance 84 is provided between the holding plate 8 and the vibration absorbing member 4. This is to sufficiently develop the vibration absorbing effect of the vibration absorbing member 4, and here 8 [
■], but 1 to 5 [rin] is good.

FIG. 3 shows a second embodiment of the present invention in which the fuel pump is installed outside the fuel tank.

The fuel passes through the suction vibrator 16 and is conveyed to the fuel pump via a rubber hose (not shown). The difference from the first embodiment is that the fuel pump is not attached to the flange 8;
The point is that the vibro 16 corresponds to the suction vibrator 16 of the fuel pump in the second embodiment, whereas it is the discharge vibro 16 of the fuel pump in the first embodiment. Further, in the second embodiment in which 10 is a fuel pump and E is an engine, although the amount of vibration transmitted to the fuel pump main body is small, the pulsation caused by fluctuations in the suction pressure of the fuel pump causes the suction vibrator 16 to vibrate. The vibration transmitted to the flange 8 is quite large.A vibration absorbing member 4 is provided to absorb this vibration, and prevents and suppresses the vibration from being transmitted to the fuel tank 1.

Next, a third embodiment, which is a slight modification of the second embodiment, will be described. This has a diaphragm structure as shown in Figure 4, and in this case, the vibration absorbing member 14 is attached to the flange 1.
8, is bonded with an adhesive that is gasoline resistant and has a sealing effect. Although wire-shaped fasteners 9 and adhesive are used to fix the vibration absorbing members 4 and 14 and the flanges 8 and 18 in FIG. 8 and FIG. The vibration absorbing members 4 and 14 are connected to the flange 8
and 18 may be burned. The point is that the vibration absorbing plates 4 and 14 can be fixed to the flanges 8 and 18 without leaking fuel.

In addition, the material of the vibration absorbing member does not need to be rubber as long as it is an elastic body, has corrosion resistance, and does not allow gasoline to penetrate.The thickness, hardness, etc. of the material may be selected appropriately depending on the weight, vibration frequency, etc. of the fuel pump. good.

FIG. 5 shows the results of a vehicle interior noise measurement experiment when using the pipe outlet shown in FIG. 4, which is the eighth embodiment, and when using the conventional pipe outlet. This will stop the engine and
'Indicates the overall value of the cabin noise measured using the mu characteristics when the fuel pump is operated in the Iji flow system. show. The fuel wrinkle at this time is 161. Vibration absorbing member 14
The thickness was t3° and the hardness was 60°. Tank capacity is 50
1. The material of the vibration absorbing member was NBR (rubber).

Also, in Figure 11a5, y is a microphone and P is a pump.

T indicates the position of the tank. Also, the dash-dotted line is the conventional example.

The solid line is the characteristic curve of the present invention.

As described above, in the present invention, even if the flange vibrates, the transmission to the fuel tank is interrupted, so resonance of the fuel tank can be prevented and noise generation can be prevented.

Additionally, the metal plate that crimps and fixes the vibration absorbing member to the flange surface installed on the fuel tank has the special effect of preventing the flange from rising when the internal pressure of the fuel tank increases due to temperature, etc. .

[Brief explanation of the drawing]

FIG. 1 is an external view of a fuel tank according to the first embodiment of the present invention;
The second reason is a partial cross-sectional front view of the first embodiment of the present invention showing the fuel pump and piping extraction structure when the fuel pump is installed in the fuel tank, and FIG. FIG. 4 is a partial sectional view showing the piping extraction structure when the pump is installed outside the fuel tank, FIG. 4 is a partial sectional view showing the eighth embodiment of the present invention, and FIG. 5 is the one according to the eighth embodiment. FIG. 3 is a diagram illustrating vehicle interior noise characteristics in comparison with a conventional one. lO...Fuel pump, 16.6.7...Fuel piping. 14.4... Vibration absorbing member, 1... Fuel tank, 1
8゜8...flange, 3...metal plate. Representative Attorney ± 8 Part Takashi Figure 1 Figure 2 F

Claims (1)

[Claims] l) A metal 7 lange with a fuel pipe connected to the fuel pump attached and a vibration absorbing member joined to the outer periphery;
A metal plate is crimped to fix the vibration absorbing member to a flange surface installed on the fuel tank, and when the internal pressure of the fuel tank increases, this metal plate prevents the displacement of the vibration stage storage member and the flange. A fuel tank piping extraction structure, characterized in that it constitutes a means for suppressing.