JP2002295327A - Fuel supply system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a fuel supply system 1 making the flow of fuel from a fuel pump 5 to a filter 9 smooth by improving the structure of a fuel passage from the fuel pump 5 to a delivery pipe 10, and making the system small. SOLUTION: As a fixing means for fixing the fuel pump 5 to a housing, projection 5c is installed in a upper end part of the fuel pump 5 and a recess 6 fitting to the projection 5c is installed in a unit cap 6b. A discharge port 7 of the fuel pump 5 is opened in a dirty side space 19 surrounded by an outer shell surface 18 which is a part of each of an end surface 8a of the filter element 8, an inner circumferential surface 17 of a housing 6, and an outer circumferential wall part 5a of the fuel pump 5, in the lower part of the fixing means, and thereby, a volume space for the flow of fuel toward the filter element 8 is made compact, the flow of fuel from the outer shell surface 18 of the fuel pump 5 to the filter element 8 is made smooth, and the system is made compact.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a fuel supply device in which a fuel pump for pumping fuel is installed in a fuel tank.

[0002]

2. Description of the Related Art Conventionally, a fuel supply device in which a fuel pump for pumping fuel and a filter for filtering fuel discharged from the fuel pump are housed in a housing and integrally assembled is housed in a fuel tank. A so-called in-tank type fuel supply device is known (Japanese Patent Laid-Open No.
2-13091, JP-A-9-268956, etc.). This fuel supply device is provided with a fuel pump that draws up fuel in a fuel tank from a lower suction port, pressurizes the fuel, and discharges the fuel from a discharge port provided above. A fuel injection device for an internal combustion engine includes a housing for accommodating the fuel pump therein, a filter for filtering fuel on an inner wall portion of the housing and an outer peripheral wall portion of the fuel pump. To supply.

[0003] As described above, the fuel pump having the fuel flow path that passes through the inside and discharges upwards recovers and cools the heat generated by the motor for fuel pumping built in the fuel pump, thereby improving the life of the motor. ing. Further, the fuel pump and the filter are compactly housed inside the housing.

[0004]

However, Japanese Patent Laid-Open No. 6-2 / 1994
The discharge port of a fuel pump used for an in-tank type fuel consuming device including the fuel supply device disclosed in JP-A-13091 and JP-A-9-268956 has a discharge pipe formed in a pipe shape. ing. This is based on the concept of connecting the discharged pressurized fuel to the front chamber space of the filter, ie the dirty side space.
That is, the outer peripheral portion of the discharge pipe serving as the discharge port is inserted into the entrance of the dirty side space that fits with the outer peripheral portion, and the seal member is provided at this insertion portion.
The discharge pipe faces upward so that the fuel flow sucked from below can be smoothly passed through the pump and discharged.

When the fuel pump having the discharge pipe and the filter are accommodated in the housing, the flow of the fuel discharged above the discharge pipe must be U-turned in the direction of the filter. Since a volume and a volume space for making the fuel discharged from the discharge pipe make a U-turn in the direction of the filter are required, the size of the fuel supply device is problematic.

SUMMARY OF THE INVENTION In view of the above, an object of the present invention is to provide a fuel supply device in which the structure of a discharge port of a fuel pump is devised so that the flow of fuel from the fuel pump to the filter becomes smooth and the size can be reduced. It is in.

[0007]

According to a first aspect of the present invention, there is provided a fuel supply device which is disposed in a fuel tank and pumps up the fuel in the fuel tank from below. A fuel pump that discharges from a discharge port provided above the outer peripheral wall portion after pressurizing and pressurizing, a housing accommodating the fuel pump inside, and an inner wall portion of the housing and an outer peripheral wall portion of the fuel pump, which are sandwiched between the discharge port and An upper end face of the filter, comprising: a filter for passing the discharged fuel downward from above and filtering the fuel; and a fixing means for fixing both the upper end portion above the discharge port of the fuel pump and the housing. , In the inner peripheral surface of the housing and the dirty side space surrounded by the outer peripheral wall of the fuel pump,
The discharge port is open.

Accordingly, a fixing means for fixing the upper end of the fuel pump and the housing between the discharge port and the upper end of the fuel pump, the inner peripheral surface of the housing, and the outer peripheral wall of the fuel pump is provided. By opening the discharge port of the fuel pump in the enclosed dirty side space, a volume space for fuel flow in the direction of the filter can be formed compactly. Therefore, it is possible to provide a fuel supply device in which the flow of fuel from the fuel pump to the filter becomes smooth and the size of the fuel supply device can be reduced.

According to the second aspect of the present invention, the fixing means has a convex portion formed at the upper end of the fuel pump and a concave portion fitted with the convex portion formed on the housing, so that the fixing means is simple and compact. The structure can stabilize the position between the housing and the pump.

According to the third aspect of the present invention, by forming a plurality of discharge ports at different positions on the outer peripheral wall of the fuel pump, the distribution of fuel discharged from the discharge ports to the filter is improved. There is an effect that the fuel distribution passing through the filter is made uniform, and the resistance of the fuel flow is reduced without increasing the volume of the dirty side space.

According to the fourth aspect of the present invention, the filter is made of a bare material of the filter element, and is arranged so that the filter element and the outer peripheral wall of the fuel pump are in direct contact with each other.

Here, the fuel pump has a motor that rotates at a high speed inside, and rotates the built-in pump to pressurize the fuel. High-frequency vibration due to the rotation of the motor is transmitted to the outer peripheral wall of the fuel pump. . Therefore, by adopting a configuration in which the outer peripheral wall portion and the bare material of the filter element are in direct contact, the flexible filter element acts as an interference member,
High frequency vibration can be attenuated. in this way,
High frequency vibrations from the outer peripheral wall can be attenuated without increasing the radial dimension of the fuel pump.

According to a fifth aspect of the present invention, a housing including a fuel pump is housed therein, and a sub-tank having an intake for taking fuel in the fuel tank is provided. It has a support portion arranged substantially parallel to the outer peripheral surface of the housing, and has a configuration in which both ends of the support portion are connected to the sub tank and the housing, respectively.

That is, a supporting portion for connecting the sub-tank and the housing in the fuel supply device having the sub-tank is provided. The support is disposed substantially parallel to the outer peripheral surface of the housing, and both ends of the support are connected to the sub tank and the housing.

Thus, the connection length between the sub-tank and the housing is extended by disposing the support portion substantially in parallel with the outer peripheral surface of the housing. Thereby, it is possible to reduce a minute vibration such as a fuel flow sound and a motor operation sound that propagate from the housing to the sub-tank, and to stabilize both positions while shortening the arrangement distance between the housing and the sub-tank.

According to a sixth aspect of the present invention, the inner peripheral surface and the outer peripheral wall of the housing in the axial direction of the fuel pump are provided in contact with each other.

Thus, fuel is discharged from a discharge port provided above the outer peripheral wall of the fuel pump, and is provided in contact with the inner peripheral surface and the outer peripheral wall of the housing in the axial direction of the fuel pump. Therefore, the dimension in the axial direction of the fuel pump can be reduced, and the fuel supply device can be downsized.

According to a seventh aspect of the present invention, the projection formed at the upper end of the fuel pump projects in the axial direction of the fuel pump from the end face of the filter, and the housing includes a large-diameter housing forming a large-diameter cylindrical portion. A small-diameter housing projecting from the bottom surface of the large-diameter housing and forming a concave portion, and the dirty side space has an inner peripheral surface formed by an inner-diameter wall surface of the large-diameter housing and a bottom surface of the large-diameter housing; , And an outer peripheral wall portion.

Thus, the housing is formed while forming the concave portion from the large-diameter housing to the small-diameter housing, and the formed concave portion is fitted to the convex portion formed at the upper end of the fuel pump. A dirty side space surrounded by an inner peripheral surface formed by the inner diameter wall surface of the large diameter housing and the bottom surface of the large diameter housing, the filter end surface, and the outer peripheral wall portion is formed. As described above, the dirty side space formed by devising the shape of the housing forms a space in which fuel can be discharged from the discharge port of the fuel pump, and the outermost diameter and the maximum diameter of the housing for providing the dirty side space. Since it does not affect the axial length, it can contribute to downsizing of the fuel supply device.

According to an eighth aspect of the present invention, the fuel pump is driven by a motor, and the pressurized fuel cools the motor and is discharged from a discharge port.

Accordingly, the pressurized fuel cools the motor and is discharged from the discharge port, which has the effect of extending the life of the motor.

[0022]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, a fuel supply device according to the present invention will be described in detail with reference to the drawings. The fuel supply device described below is provided in, for example, a vehicle, and includes a fuel pump for pumping fuel and a filter for filtering fuel discharged from the fuel pump housed in a housing and integrally assembled. This is a so-called in-tank type fuel supply device in which the fuel supply device is accommodated in a fuel tank. When the fuel in the fuel tank is pumped up from the lower suction port and pressurized and then discharged from the upper discharge port, the structure of this discharge port is devised to smooth the flow of fuel from the fuel pump to the filter. And a technology that contributes to downsizing of the fuel supply device.

First, a schematic configuration of a fuel supply device for supplying fuel to an internal combustion engine serving as a fuel consumption device will be described with reference to FIG. As shown in FIG. 6, the fuel supply device 1 is housed in a fuel tank 2. The fuel stored in the fuel tank 2 is driven by a motor provided in the fuel pump, pumped up and pressurized. The pressurized fuel is passed through the motor section to cool the motor, and then discharged from the discharge port. Then, all of the discharged fuel is passed through a filter described later, and the fuel is supplied to the internal combustion engine 4 through the fuel conduit 3.

Next, the overall structure of a fuel supply device 1 according to one embodiment of the present invention will be described with reference to FIG. In addition, FIG.
It is BB sectional drawing of FIG. 2 mentioned later. As shown in FIG. 1, the fuel supply device 1 includes a fuel pump 5, a housing 6 accommodating the fuel pump 5 therein, an inner wall of the housing 6 and an outer peripheral wall 5 a of the fuel pump 5, and a discharge port 7. A filter 8 for passing the fuel discharged from the filter downward from above and filtering the fuel, a pressure regulator 9 for regulating the pressurized fuel passing through the filter 8, and a fuel regulated by the pressure regulator 9. It is composed of an outlet pipe 10 and the like. Note that 11
Is a strainer, which separates and filters foreign substances so as not to be caught in a pump section built in the fuel pump 5. Further, an intake port 12a is provided to accommodate the housing 6, and takes in fuel in the fuel tank 2.
A sub-tank 12 having (FIG. 2) is provided.

The fuel pump 5 has a suction port 13 at the lower side, and a fuel pump for driving the motor (not shown) and a fuel pressure feeding motor built in the fuel pump 5 lowers the fuel in the fuel tank 2 downward. From the suction port and discharge upward. In this way, the fuel passing through the interior collects and cools the heat generated by the motor, thereby satisfying the durability of the motor. The fuel pressurized by the pump unit is discharged from a discharge port 7 provided above the outer peripheral wall 5 a of the fuel pump 5. Details of the discharge port 7 will be described later. Reference numeral 23 denotes a flange fixed to the fuel tank 2, and the flange 23 has a connector 23a.
Is provided. Power is supplied to the motor from the connector 23a. Also, two electric wires 25 extending from the connector 23a.
Penetrates the unit cap 6b and reaches a convex portion 5c of the fuel pump 5 which will be described later. For this purpose, a through hole 6ba is formed in the unit cap 6b.

The housing 6 includes a unit housing 6a
And a unit structure of the unit cap 6b, and is formed of polyacetanol as a resin material. Then, after the fuel pump 5 is accommodated in the unit housing 6a together with the filter element 8 in a bare material state, which will be described later, the unit cap 6b is covered and the two members 6a and 6b are melt-bonded. The fuel pump 5 is inserted into the housing 6 described above.
The lower part and the upper part of the fuel pump 5 are fixed to the unit housing 6a and the unit cap 6b, respectively, and are urged by the rubber member 24 so as not to move in the axial direction. Also, the end face 6bc of the unit cap 6b
Is an end surface 24 of the rubber member 24 on the unit cap 6b side.
a.

Below the fuel pump 5, a convex portion 5b is formed at the lower end of the fuel pump 5, and a concave portion 6A that fits with the convex portion 5b is formed in the unit housing 6a, and the convex portion 5b and the concave portion 6A are fitted. A sealing member (O-ring) 14 is interposed in the joint portion. Above the fuel pump 5, the inner peripheral surface 7 of the housing 6 in the axial direction of the fuel pump 5 and the outer peripheral wall 5a of the fuel pump 5 are provided in contact with each other.

That is, the protrusion 5c is formed at the upper end of the fuel pump 5.
Is formed on the unit cap 6b, and a seal member (O-ring) 15 is interposed at the fitting portion between the convex portion 5c and the concave portion 6B.
More specifically, the protrusion 5 formed at the upper end of the fuel pump 5
c protrudes from the end face 8a of the filter 8 in the axial direction of the fuel pump 5, and the housing 6 has a large-diameter housing 6aa forming a large-diameter cylindrical portion and a bottom surface 17a of the large-diameter housing 6aa.
Small diameter housing 6 projecting from
bb.

As described above, the convex portion 5c and the concave portion 6B at the upper end of the fuel pump 5 constitute fixing means according to the first aspect. In addition, the above-mentioned sealing member (O-ring) 1
Reference numerals 4 and 15 are provided to prevent the fuel pressurized by the fuel pump 5 from leaking out of the housing 6. With the above-described configuration, the fuel is discharged from the discharge port 7 provided above the outer peripheral wall 5a of the fuel pump 5, and the inner peripheral surface 7 of the housing 6 in the axial direction of the fuel pump 5 is brought into contact with the outer peripheral wall 5a. Provided. Therefore, the dimension of the fuel pump 5 in the axial direction can be reduced, and the size of the fuel supply device 1 can be reduced.

The filter 8 is sandwiched between the inner wall 16 of the unit housing 6a and the outer wall 5a of the fuel pump 5 without any gap, and filters the fuel discharged from the discharge port 7 of the fuel pump 5. The filter 8 in the present embodiment is made of a bare material of the filter element 8, and the filter element 8 and the outer peripheral wall 5 of the fuel pump 5 are formed.
a is configured to be in direct contact with a.

As a result, high-frequency vibrations caused by the motor and the pump section rotating at high speed inside the fuel pump 5 are transmitted to the outer peripheral wall 5a of the fuel pump 5, but the outer peripheral wall 5a
With a configuration in which a and the filter element 8 are in direct contact with each other, the flexible filter element 8 functions as an interference member, and can attenuate high-frequency vibration.
In this manner, high-frequency vibrations from the outer peripheral wall 5a are attenuated without increasing the radial dimension of the fuel pump 5.

The fuel pump 5 has a projection 5 above it.
c and the concave portion 6B of the unit cap 6b are fitted, and the convex portion 5b and the concave portion 6A of the unit housing 6a are fitted and fixed below the concave portion. Can be avoided.

Below the fixing means consisting of the convex portion 5c and the concave portion 6B, the upper end surface 8a of the filter element 8, the inner wall portion 16 of the large-diameter housing 6aa and the bottom surface 17a of the large-diameter housing 6aa are formed. The discharge port 7 of the fuel pump 5 is opened in a dirty side space 19 surrounded by an inner peripheral surface 17 of the housing 6 and an outer peripheral surface 18 which is a part of the outer peripheral wall 5 a of the fuel pump 5. More specifically, the fuel passage that rises in the axial direction from the lower side of the fuel pump 5 is defined as an L-shaped fuel passage 20 that is bent in the radial direction of the fuel pump 5 on the outer peripheral wall 5a below the fixing means. The opening end of the U-shaped fuel passage 20 is opened in the dirty side space 19, and one discharge port 7 is formed.

As described above, as a result of the sealing by the seal member 15, the fuel in the dirty side space 19 passes through the through hole 6b.
does not reach a. The fuel that has cooled the motor unit while being pressurized in the fuel pump 5 contains foreign matter generated from the motor unit, such as contaminants and abrasion powder of the brush.
The filter element 8 can pass through the dirty side space 19 without being released to the outside of the unit cap 6b by the seal member 15. If such a sealing member 15 is not provided, abrasion powder of contaminants and brushes is discharged into the fuel tank 2 and sucked by the fuel pump 5 again.
It is conceivable that the life of the sealing member 15 is shortened.
Can prevent it.

The seal member 15 defines a dirty side space 19. End surface 2 of rubber member 24
4a is in contact with the end face 6bc of the unit cap 6b, and the end face 5d of the fuel pump 5 on the unit cap 6b side.
And the end face 6bc of the unit cap 6b merely forms a minute gap. With this seal member 15, the dirty side space 19 can be partitioned, and the other space can be reduced. Dirty side space 1
By making 9 the minimum necessary volume, the volume of the housing 6 in which it is formed can be reduced. In addition, since the weight of the housing 6 can be reduced, the housing 6 can be hung from the flange 23 without being integrated with the flange 23 over the entire assembly.

As described above, the volume space for the fuel flow in the direction of the filter element 8 can be made compact. Therefore, the fuel flow from the outer peripheral wall 5a of the fuel pump 5 to the upper end face of the filter element 8 via the shortest path becomes smooth without intervening the intermediate path unlike the related art, and the intermediate path can be omitted to reduce the size. It becomes possible.

Next, the support portion 21 for connecting the housing 6 and the sub-tank 12 will be described with reference to FIGS. FIG. 2 is a top view of the fuel supply device in FIG. 1 as viewed from above the line AA, and FIG. 3 is a partial perspective view showing the support portion 21 in FIG. The connection between the housing 6 and the sub-tank 12 has a support portion 21 arranged substantially parallel to the outer peripheral surface 22 of the unit housing 6a to be the housing 6, and both ends of the support portion 21 are connected to the sub-tank 12 and the unit housing 6a, respectively. The configuration was adopted.

The support portion 21 has a thin plate shape made of a resin material and is disposed substantially parallel to the outer peripheral surface 22 of the unit housing 6a to extend the connection length. Thereby, it is possible to reduce a minute vibration such as a fuel flow sound and a motor operation sound transmitted from the unit housing 6a to the sub-tank 12, and to stabilize the positions of the two housings 6a and 12 while shortening the arrangement distance between the unit housing 6a and the sub-tank 12. Can be done.

(Modification) FIGS. 4 and 5 show a fuel supply device 1 according to a modification of the present invention. 4 and 5 are partial cross-sectional views showing the periphery of the discharge port in the fuel supply device 1 according to the modified example. Components that are substantially the same as those in the embodiment shown in FIG. 1 are given the same reference numerals, and descriptions thereof are omitted. In addition,
FIGS. 4 and 5 show the fuel supply device 1 shown in FIGS.
However, the configuration around the discharge port is different.

As shown in FIG. 4, a fuel passage which rises in the axial direction from below the fuel pump 5 is branched radially in the fuel pump 5 into a plurality of fuel passages. 5 are respectively opened as discharge ports 7a at different positions on the outer peripheral wall 5a, and are respectively opened in the dirty side space 19. In this modification, an example in which four discharge ports 7a are formed is shown. Thereby, the distribution of the fuel discharged from the discharge port 7a to the filter element 8 is improved, the fuel distribution passing through the filter element 8 is made uniform, and the resistance of the fuel flow is reduced without increasing the volume of the dirty side space 19. Has the effect of being done.

As shown in FIG. 5, a fuel passage which rises in the axial direction from below the fuel pump 5 to the upper part is opened in the dirty side space 19 to serve as a discharge port 7b. In this case, to secure a space above the fuel pump 5 where the periphery of the discharge port 7b and the dirty side space 19 are connected,
A convex portion 5c formed on the upper end of the fuel pump 5 and the unit cap 6b, and a concave portion 6B fitted with the convex portion 5c
Is displaced from the axial center position of the fuel pump 5.

In the practice of the present invention, the convex portion 5c and the concave portion 6B fitted with the convex portion 5c are formed in the unit cap 6b at the upper end of the fuel pump 5, but the fixing means is not limited to this. Instead, any configuration may be used as long as the fuel pump 5 can be fixed to the housing.

In the embodiment of the present invention, the sub-tank 12 is provided so as to accommodate the unit housing 6a. However, the fuel supply device 1 without the sub-tank 12 may be used.

[Brief description of the drawings]

FIG. 1 is an overall configuration front view showing a fuel supply device according to an embodiment of the present invention.

FIG. 2 is a top view of the fuel supply device in FIG. 1 as viewed from above the line AA.

FIG. 3 is a partial perspective view showing a support portion 21 in FIG.

FIG. 4 shows a discharge port 7a in a fuel supply device according to a modified example.
It is a fragmentary sectional view showing the circumference.

FIG. 5 is a discharge port 7b in a fuel supply device according to a modified example.
It is a fragmentary sectional view showing the circumference.

FIG. 6 is a schematic configuration diagram illustrating a fuel supply device that supplies fuel to the internal combustion engine.

[Explanation of symbols]

 REFERENCE SIGNS LIST 1 fuel supply device 2 fuel tank 4 internal combustion engine 5 fuel pump 5 a (outer side of fuel pump) outer peripheral wall portion 5 c (upper part on fuel pump side) convex portion 6 housing 6 a unit housing (part of housing) 6 aa large-diameter housing 6 b Unit cap (constitutes part of the housing) 6bb Small-diameter housing 6B Recess 7, 7a, 7b (at upper end on housing side) Discharge port 8 Filter element (filter) 12 Subtank 12a Intake port 16 (Housing) inner wall 18 (Fuel) Outer surface of pump 19 Dirty side space 21 Support

Claims (8)

[Claims] 1. A fuel pump disposed in a fuel tank, which pumps fuel in the fuel tank from below and pressurizes the fuel, and then discharges the fuel from a discharge port provided above an outer peripheral wall portion. A filter that is sandwiched between an inner wall portion of the housing and the outer peripheral wall portion of the fuel pump, and that filters the fuel discharged from the discharge port by passing the fuel downward from above and filtering the fuel; Fixing means for fixing between an upper end portion of the pump above the discharge port and the housing, an upper end surface of the filter, an inner peripheral surface of the housing,
And a discharge port opening in a dirty side space surrounded by the outer peripheral wall of the fuel pump. 2. The fuel pump according to claim 1, wherein the fixing means has a convex portion formed on the upper end portion of the fuel pump and a concave portion fitted with the convex portion formed on the housing. Fuel supply device. 3. The fuel supply device according to claim 1, wherein a plurality of the discharge ports are formed at different positions on the outer peripheral wall of the fuel pump. 4. The filter according to claim 1, wherein the filter is made of a bare material of a filter element, and the filter element is arranged so that the filter element and the outer peripheral wall of the fuel pump are in direct contact with each other. The fuel supply device according to claim 3. 5. A sub-tank which accommodates the housing including the fuel pump therein and has an intake for taking fuel in the fuel tank, wherein the sub-tank and the housing are connected to each other by an outer periphery of the housing. 5. The device according to claim 1, further comprising a support portion arranged substantially parallel to a surface, wherein both ends of the support portion are connected to the sub-tank and the housing, respectively. 6. Fuel supply system. 6. The fuel supply device according to claim 2, wherein the inner peripheral surface of the housing and the outer peripheral wall in the axial direction of the fuel pump are provided in contact with each other. 7. A projection projecting from an end face of the filter in an axial direction of the fuel pump, the housing projecting from a bottom surface of the large-diameter housing forming a large-diameter cylindrical portion, and forming the recessed portion. The dirty side space is formed by the inner peripheral surface formed by the inner wall portion of the large diameter housing and the bottom surface of the large diameter housing, the filter end surface, and the outer peripheral wall portion. 3. The fuel supply device according to claim 2, wherein the fuel supply device is formed so as to be surrounded. 8. The fuel supply device according to claim 1, wherein the fuel pump is driven by a motor, and the pressurized fuel cools the motor and discharges the fuel from a discharge port.