JPH0323360A - Fuel pump - Google Patents

Abstract

PURPOSE:To disperse kinetic energy of vapor-mixed fuel and to reduce the generation of noise and vibration by a method wherein a shield member is disposed between the outlet of a vapor escape passage communicated from a pump chamber to a fuel tank and a fuel tank positioned facing the outlet. CONSTITUTION:A vapor escape passage 50 and a radially extending groove 52 are formed in a housing body 26 with which a plurality of the impellers, not shown, of a fuel pump are covered, and a cushioning material 54 is provided. In this case, a protrusion 58 serving as a shield member to close the opening end of the groove 52 is formed on the cushioning material 54, and partitions a chamber 62. A small through-passage 60 is formed in the protrusion 58. After vapor mixed in fuel is guided in a chamber 62 through the vapor escape passage 50, it is discharged through the through-passage 60, serving as a throttle part, to the interior of a fuel tank. This constitution causes dispersion of kinetic energy of vapor-mixed fuel and reduces the generation of vibration and noise.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Field of Application] The present invention mainly relates to fuel pumps used in automobiles.

[Prior Art Ili1] As this type of fuel pump, those shown in FIGS. 4 to 7 are widely used.

Here, a conventional fuel pump will be explained.

As shown in FIG. 4, the fuel pump 2 is mounted substantially vertically within the fuel tank 4 via a bracket 6. As shown in FIG.

As shown in FIG. 5, this fuel pump 2 includes a cylindrical housing 8, a motor part 10 disposed on the upper part of the housing 8, and a cover member 12 attached to the lower part of the housing 8. It consists of all 4 pumps.

Here, the pump section 14 will be described in detail.
The drive shaft 18 of the rotor 16 of the N@ motor constituting 0 is inserted into a hole formed in the center of the cover member 12. A first invera 20 and a second invera 22 that rotate together with the drive shaft 18 are attached to the drive e-shaft 18.

These impellers 20.22 have a plurality of notches 24 along their outer periphery. Further, a housing body 26 that covers the inflator 20.22 is fixed to the cover member 12 by a screw 32 via a plate 28 and a pair of spacers 30 disposed with the plays 1 and 28 in between.

If a gap is formed between the outer circumferential edge of the invera 20.22 and the inner circumferential edge of the spacer 30, the cover member 12,
The plate 28 and the housing body 26 have a flow route groove 34. Each of the outer rim of the Inbera 20.22, respectively.
36, 38, and 40 are formed. This allows the first
A C-shaped first pump chamber 42 and a second pump chamber 44 are formed around the invera 20 and the second invera, respectively. Both pump chambers 42 and 44 communicate with each other through a through hole (not shown) formed in the plate 28. Furthermore, the second pump chamber 44 is connected to the cover member 12.
The first pump chamber 42 is communicated into the fuel tank 4 through an inlet boat 48 formed in the housing body 26 .

As roughly shown in the bottom view of the housing body 26 in Figure 6, the housing body 26 is formed with a small diameter paper escape passage 50 that communicates with the first pump chamber 42.

This vapor relief passage 50 is for removing paper from the fuel flowing in the first pump chamber 42, and is provided at a position substantially symmetrical to the inlet boat 48 with respect to the center of the housing body 26. Further, a groove 52 is formed in the housing body 26 at a portion where the vapor relief passage 50 is formed. This groove 52 extends in the radial direction of the housing body 26.

The pump 2 is attached to the bracket 6 with a cushioning material 54 as shown in FIG. 7 interposed in the lower part of the housing body 26 constructed as described above. As a result, the passage 52 is covered, and the passage 5 opened to the peripheral wall of the housing body 26 by the cushion material 54 and the passage 52 is covered.
6 will be formed. Therefore, the paper escape passage 5
0 opens into the fuel tank 4 through this passage 56.

Next, the operation of the wIFl pump 2 configured as described above will be explained.

First, when the inflator 20.22 rotates, the pressure in the first pump chamber 42 is increased and the fuel is guided into the second pump chamber 44 through the through hole formed in the plate 28. This fuel is further pressurized within the second pump chamber 44. Due to the two-step pressurizing action by the invera 20.22, fuel is sucked from the inlet boat 48, and both pump chambers 42.4
4 and is pumped from the outlet boat 46 into the housing 8.

In this case, the paper generated due to the temperature inside the fuel tank 4 or the paper generated due to the fuel suction action passes through the paper relief passage 50 and the passage 56 formed in the housing body 26 as paper-mixed fuel to the fuel tank. The paper content in the fuel discharged into the housing 8 and pumped into the housing 8 is reduced. As a result, the vapor content of the fuel sent from the housing 8 to the engine (not shown) is naturally reduced, and the so-called paper lock phenomenon is prevented.

However, in the fuel pump configured as described above, the vapor-mixed fuel flows through the vapor relief passage 50 and the oil passage 56.
There is a lot of noise when the fuel is discharged through the fuel tank 4 into the fuel tank 4. This is because there is a large pressure difference between the high-pressure inside of the pump chamber and the low-pressure inside of the fuel tank, and also because the opening of the passage 56 is open in one direction from the inside wall of the fuel tank. This is thought to be the effect of vibrations caused by the kinetic energy of the discharged high-pressure paper-containing fuel being propagated to a portion of the inner wall surface of the fuel tank via the fuel in the fuel tank. Furthermore, it is thought that the paper-mixed fuel contains sound components generated around the invera during pump rotation, and this is amplified in the space within the stripping tank, etc., and generates noise. The sound generated around the invera is a relatively high frequency noise (4 to 6κ11Z) determined by the number of inveter blades×the invera rotation speed.

In recent years, with the improvement of the quietness of vehicles, the vapor relief passage 50
The proportion of the noise emitted from the passageway 56 in the indoor noise has become relatively large, and the need for soundproofing measures against the emitted sound has increased.

Note that this discharge noise is louder as the pump has a larger capacity, that is, there is more discharge noise from the paper relief passage.
There is a particularly high need for soundproofing measures for such large-capacity pumps.

An example of soundproofing the paper escape passage is disclosed in Japanese Patent Application Laid-Open No. 121891/1983. This prior art attempts to obtain a silencing effect by obstructing the passage following the vapor relief passage.

[Problems to be Solved by the Invention] However, this conventional soundproofing measure does not suppress to some extent the relatively high frequency (4 to 6 KHz) sound generated from the area around the impeller that is transmitted from the paper relief passage to the space inside the fuel tank. It is possible to do 1jl. However, since the outlet of the vapor relief passage is open toward one direction on the inner wall of the fuel tank, the kinetic energy possessed by the high-pressure paper-containing fuel released from the outlet is transferred internally through the fuel in the fuel tank. It is not possible to reduce the vibrations that occur because they are concentrated on a portion of the wall surface and are propagated.

Based on the above knowledge, the present invention reduces the kinetic energy held by the paper-mixed fuel by appropriately dispersing the paper-mixed fuel that wanders out from the paper escape passage, and concentrates it on a part of the inner wall surface of the fuel tank. The solution is to suppress vibrations and reduce noise by preventing the noise from being propagated and also by dispersing or absorbing relatively high-frequency sounds from the area around the impeller contained in the paper-mixed fuel. This is the next subject to be addressed.

[Means for solving v1 problem] The above problem consists of the following parts [! solved by a fuel pump with i.

This fuel pump has a vapor relief passage communicating from the pump chamber to the inner space of the fuel tank.

It has a roughly covering member. , the shielding member is disposed between the outlet of the paper escape passage and the inner wall of the fuel tank facing the outlet.

[Sakukawa] According to the above configuration, the vapor-containing fuel discharged from the vapor relief passage into the fuel tank hits the shielding member and is lost in portions C. Therefore, the kinetic energy held by the vapor-containing fuel is also absorbed or dispersed by the pumping member. Therefore, the kinetic energy is not concentrated on a part of the inner wall surface of the fuel tank and is not propagated.
I-motion is reduced. In addition, relatively high-frequency sound generated from the vicinity of the invera contained in the paper-mixed fuel is also absorbed or dispersed.

[Example] Next, an example of the present invention will be described based on the drawings. The basic configuration of the fuel pump of the present invention is similar to the conventional fuel pump described above, so only the different configuration will be described with reference to the drawings showing the prior art.

First, a first example will be explained. In FIG. 1, which corresponds to FIG. 7 showing a conventional example, the housing body 26 is provided with a paper escape and a passage 50, as well as a groove 52 extending in the radial direction.

And what about the paper escape passage 50? It is also included in 1I52. Further, a cushion material 54 is attached to the housing body 26.

Now, a protrusion 58 having a size that can close the front end (left end in the figure) of the groove 52 is formed on the cushion material 54. As a result, a chamber 62 is formed by the groove 52 and the cushion material 54. In addition, a small diameter through passage 60 is formed in the protrusion 58. Therefore, this chamber 6
2 is communicated with the first pump chamber 42 through the paper relief passage 50 and into the fuel tank 4 through the through passage 60. Note that the volume of this chamber 62 is set to approximately 28jlI3.

In the figure, 106 is a reflective member. The reflecting member 106 is arranged in a position facing the outlet of the through passage 60 of the chamber 62 and curved so as to be slightly concave toward the outer periphery of the fuel pump 2 . This is the covering member described in the claims. Further, in this embodiment, the repellent member 106 also serves as a bracket for fixing the fuel pump 2 within the fuel tank 4.

According to the above configuration, the paper contained in the fuel moving in the first pump chamber 42 by the suction action of the fuel pump 2 is guided into the chamber 62 through the paper relief passage 50 as paper-mixed fuel, and then The fuel is discharged into the fuel tank 4 through a passageway 60 serving as a constriction section. In this case, the vapor-mixed fuel flows through the chamber 62 and the through passage 60J.
Fr1! The ejection noise is reduced by being ejected. Further, the discharged vapor mixed fuel is reflected by the reflective member 106.
It is reflected and dispersed by colliding with the For this reason, some of the kinetic energy possessed by the fuel mixed with the vapor is transferred to the repulsion member 1.
The vibrations are absorbed by the inner wall 4 of the fuel tank and are absorbed by the inner wall 4 of the fuel tank. Relatively high-frequency sounds generated from the surroundings of the invera, which are contained in the vapor-containing fuel, are also reflected and dispersed by the repellent member 106, so that the noise is reduced.

Here, if the diameter of the through passage 60 is increased, the soundproofing effect decreases, but the provision of the reflecting member 106 improves the soundproofing effect. The diameter can be increased. member aisle 60
As the diameter of the fuel pump becomes larger, the resistance to the wandering of the vapor becomes smaller, the performance of discharging paper from the fuel pump improves, and the high temperature performance of the fuel pump becomes excellent.

Next, a second example will be described. Details of the second embodiment are shown in FIG. This embodiment further increases the exhaust energy of vapor-containing fuel on the blue surface of the anti-OA member 106 used in the first embodiment! It has a structure in which an absorbing member 108 is integrated, and this absorbing member 108 receives fuel mixed with paper. As this absorbing member 108,
For example, a porous member made of an elastic material such as a resin or rubber, or a foamed resin such as a sponge can be suitably used, and suitable methods such as baking, adhesion, coating, molding, etc. can be used as the means for temporary fixing.

Here, a metal tab 64 that can close the groove 52 and form a chamber 62 is attached to the groove 52 by a presser or the like. The cap 64 has a through passage 60.
is formed. By providing such an absorbing member 108 in the reflecting member 106, a part of the kinetic energy of the paper-mixed fuel colliding with the absorbing portion 1108 is absorbed by the absorbing member 108, and the momentum of reflection dispersion can be further weakened. . In addition, a portion of the relatively high-frequency sound generated from the periphery of the invera contained in the paper-mixed fuel is also absorbed by the absorbing member 108 . Therefore, noise can be further reduced compared to the first embodiment.

FIG. 3 is a view showing the housing body 26 of m construction shown in FIG. 2 from below.

As shown in Figure 3, vapor mixed fuel absorbs 8ls44108
When a collision occurs from an oblique direction, the collision hits a wider area than when a collision occurs head-on, so the force that tries to vibrate the absorbing member 108 becomes weaker, and the kinetic energy that is reflected and goes out becomes smaller. The repelling member 106 and the absorbing member 108 are curved slightly concavely toward the outer periphery of the fuel pump 2 so that the paper-containing fuel reflected from the surface flows in contact with the outside of the pump, thereby reducing the flow of fuel. The cooling effect of the fuel pump 2 is also obtained, thereby reducing the generation of vapor.

Furthermore, since the flow of fuel hits the absorption part, Il1ios, and the outside of the fuel pump, the fuel is further dispersed in multiple directions, resulting in the effect of reducing the overall sound.

[Effects of the Invention] According to the present invention, since the kinetic energy possessed by the paper-mixed fuel is dispersed and reduced, vibrations are not concentrated on a part of the inner wall surface of the fuel tank, and the kinetic energy contained in the paper-mixed fuel is reduced. Relatively high-frequency sounds generated around the invera where the vehicle is located are also separated, reducing noise by 4r1.

[Brief explanation of the drawing]

1 to 3 show embodiments of the present invention. FIG. 1 is a partial sectional view of a fuel pump in the first embodiment, FIG. 2 is a partial sectional view of a fuel pump in the second embodiment, and FIG. The figure is a diagram showing the fuel pump of the second embodiment from below. Figures 4 to 7 show the prior art, Figure 4 is a layout of the fuel pump, Figure 5 is a sectional view of the fuel pump, Figure 6 is a diagram showing the fuel pump from below, and Figure 7 is a diagram of the fuel pump. Vl-V in Figure 6
FIG. 2...Fuel pump 4...Fuel tank...First pump chamber 50...Vapor relief passage 106...Anti-9A member O8...Absorption member

Claims (1)

[Claims] In a fuel pump having a paper relief passage communicating from a pump chamber to an internal space of a fuel tank, a shielding member is disposed between an outlet of the paper relief passage and an inner wall of the fuel tank facing the outlet. A fuel pump featuring: