JPH0953533A - In-tank type fuel pump device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an in-tank type fuel pump device with improved assembling ability and position precision of a pump. SOLUTION: A pump case 16 is surely suspended from a flange, fixed at a fuel tank, through fitting-in of a claw part 27 by snap fit. The pump case 16 is formed of elastically deformable resin and an opening part 340 approximately in a square is formed in a surface on the outer peripheral side. Since a fuel pump 14 is inserted in the pump case 16 through a hole 350 formed by means of the opening part 340, the fuel pump is assembled to the pump case 16 in the state of a pump unit 140 to which a fuel filter 15 is previously attached. Since the width Dh of the opening part 340 is slightly lower than the maximum outside diameter Dp of the fuel pump 14, the fuel pump 14 is inserted in the pump case 16 in such a state that the opening part 340 is elastically deformed in such a manner to forcibly spread the opening part 340. This constitution prevents falling-off of the fuel pump 14 through the hole 350 after assembly.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an in-tank type fuel pump device.

[0002]

2. Description of the Related Art In order to reduce the cost of a vehicle, parts around fuel tanks are being integrated, and along with this, in-tank fuel pumps are being made. For example,
As disclosed in JP-A-3-105055, fuel discharged from a fuel pump provided in a fuel tank is pressure-fed to the outside of the fuel tank through a discharge pipe, and the pressure-fused fuel is injected from a fuel injection valve to an engine. Injection supply to the combustion chamber of
It is known that surplus fuel is returned to the sub tank through a return pipe.

Conventionally, a holding member such as a metal bracket has been used as a holding structural component of such an in-tank type fuel pump device. However, in order to reduce the cost of the vehicle, the resin around the fuel tank has been advanced, and the holding structure parts of the in-tank type fuel pump device are also being made of resin.

[0004]

By the way, a pump case for accommodating a fuel pump is designed so that the fuel pump and the pump case can be attached and detached in a state where a fuel filter is attached to the fuel pump to form a pump unit. Usually, it is composed of two parts, a cylindrical case part and a cup-shaped bracket part. For example, in the comparative example shown in FIG.
The pump case 760 includes a cylindrical case 761 and a cup-shaped bracket 762. Fuel pump 74
1 and the fuel filter 742 fixed to the lower end of the fuel pump 741 are assembled in the pump case 760, the fuel pump 741 is first inserted through the lower end opening of the cylindrical case 761 and then the cylindrical shape. The cup-shaped bracket 76 is attached to the lower end of the case 761.
2 was attached.

However, when the pump case is formed from two parts, the number of parts and the number of assembling steps are increased, and the number of parts is large, so that the positional accuracy of the pump is deteriorated. to solve this problem,
The pump case is molded as a bottomed cylindrical member without using a bracket, and the pump unit is inserted into the opening at the upper end of the pump case from the fuel filter side. It is also conceivable to house the fuel pump in the pump case by removing the fuel filter from the section. However, when the width of the fuel filter is wider than the inner diameter of the pump case, it is difficult to perform this assembling method.

An object of the present invention is to provide an in-tank type fuel pump device in which the assemblability and the positional accuracy of the pump are improved by integrating the pump case.

[0007]

[Means for Solving the Problems]

(Solution) In order to solve the above problems, an in-tank fuel pump device according to claim 1 of the present invention is a fuel pump which is provided in a fuel tank and pumps up fuel in the fuel tank; A fuel filter attached to the suction port of the pump and extending in a direction substantially perpendicular to the axial direction of the fuel pump; and a width smaller than the maximum width of the fuel pump and / or an axial length of the fuel pump on the outer peripheral side surface. It has a substantially rectangular opening with a small height, the width and / or height of the opening can be changed by elastic deformation, and the fuel pump is inserted into the inside through a hole formed by the opening. It is characterized by comprising a possible bottomed cylindrical pump case, and a flange connected to the pump case and fixed to the fuel tank.

An in-tank type fuel pump device according to a second aspect of the present invention is the in-tank type fuel pump device according to the first aspect, wherein the width of the opening is smaller than the maximum width of the fuel pump. And The in-tank type fuel pump device according to claim 3 of the present invention is defined by claim 1
In the in-tank fuel pump device described, the height of the opening is smaller than the axial length of the fuel pump.

According to a fourth aspect of the present invention, there is provided the in-tank fuel pump apparatus according to the first, second or third aspect, wherein the pump case is made of resin. An in-tank fuel pump device according to claim 5 of the present invention is the in-tank fuel pump device according to claim 4, wherein the pump case is positioned on the flange on the outer peripheral side surface of the flange side end portion. It is characterized in that it has a snap-fit portion for fixing, and the flange side end portion is connected in a ring shape.

(Operation and Effect of the Invention) According to the in-tank type fuel pump device of the first, second or third aspect, the opening is provided on the outer peripheral side surface of the pump case, and the pump case is elastically deformed. By changing the width and / or the height of the opening, the fuel pump can be attached and detached through the hole formed by the opening. Therefore, since it is not necessary to pass the fuel filter inside the pump case, even when the width of the fuel filter is larger than the inner diameter of the pump case, the fuel filter is fixed to the fuel pump while the fuel filter is fixed to the pump case. Desorption can be performed. Therefore, since it is not necessary to use the bracket, the number of parts and the number of assembling steps are reduced, and the position accuracy of the fuel pump is improved. Further, since the opening has a width smaller than the maximum width of the fuel pump and / or a height smaller than the axial length of the fuel pump, the opening formed by the opening can be provided without any special fixing means. It is possible to prevent the fuel pump from falling off after assembly.

According to the in-tank type fuel pump device of the fourth aspect, since the pump case is made of resin, the opening provided on the outer peripheral side surface of the pump case can be easily elastically deformed. is there. Therefore, when inserting the fuel pump through the hole formed by this opening, insert the fuel pump while pushing the opening wide by the fuel pump or bend the pump case so as to expand the opening in the height direction. By inserting the fuel pump, it is possible to prevent the fuel pump from dropping out from the hole formed by the opening after the assembling, without providing any special fixing means.

According to the in-tank fuel pump device of the fifth aspect, since the flange-side end portion of the pump case having the snap-fit portion is connected in a ring shape,
The shape of the end portion on the flange side is stable, and is less likely to be deformed to the inner diameter side due to heat or aging. Therefore, there is an effect of preventing the snap fit portion from coming off the flange.

[0013]

BEST MODE FOR CARRYING OUT THE INVENTION An embodiment of the present invention will be described below with reference to the drawings. An embodiment of the in-tank fuel pump device of the present invention is shown in FIGS. 9 and 10
As shown in, an in-tank fuel pump device 2 is mounted inside the fuel tank 1. The upper tank 3 and the lower tank 4 made of metal are sandwiched and fixed by an insulator 5, bolts 11 and nuts 12. A supply pipe 6 is connected to a fuel filler port 10 of the upper tank 3 with a rubber boot 7 interposed. A sub-tank 8 is installed inside the lower tank 4, and a communication pipe 9 that connects the inside and the outside of the sub-tank 8 of the lower tank 4 is provided.

A fuel filter 15 for the fuel pump, a pump case 16 for accommodating the fuel pump 14, a supply pipe 17, a supply pipe 18 and a return pipe 19 branched from the supply pipe 17, are provided inside the sub-tank 8. A pressure regulator 22 that adjusts the pressure in the pressure chamber with a non-conductive diaphragm and a spring and a secondary filter 23 that filters fuel with a non-conductive filter element provided inside are provided. The flange 24 attached to the upper tank 3 is formed by integrally molding a tube, an electrical connector 39, and a component such as a bracket from an elastically deformable resin such as polyacetal. A pressure regulator 22 and a secondary filter 23 are fixed to the inside of the fuel tank 1 of the flange 24 by hanging or the like. Further, a pump case 16 is suspended on the inside of the fuel tank 1 of the flange 24. The electrical connector 39 is electrically connected to a vehicle wire harness (not shown). As shown in FIG. 9, a sender gauge 41 as a liquid level gauge for detecting the liquid level of the fuel in the tank is attached to the outside of the pump case 16. Note that the sender gauge 41 is omitted in FIG. 10.

The fuel pumped by the fuel pump 14 through the fuel filter 15 is pumped from the supply pipe 17 and pumped from the return pipe 19 to the pressure regulator 22 on the fuel tank 1 side, and the pressure regulator 22 regulates it to a constant pressure. It is then pressure-fed from the supply pipe 18 to the engine side. The surplus fuel passes through the pressure regulator 22, is filtered by the secondary filter 23, and is returned to the fuel tank 1.

Pump case 16 and this pump case 16
The pump unit 140 and the sender gauge 41 that are assembled in the above will be described in more detail. Pump Unit 140 As shown in FIG. 8, the pump unit 140 includes a fuel pump 14 and a fuel filter 15. Fuel pump 14
Is composed of a pump portion 71 that sucks in fuel, a motor portion 72 that drives the pump portion, and a discharge portion 73 that discharges fuel from the pump portion 71 through the motor portion 72. A spacer 65, an O-ring 64, and a cap 63 are attached to the ejection portion 73. Further, the fuel pump 14 has an electric supply unit 74 for supplying a drive current for the motor. FIG.
As shown in FIG. 7, the fuel pump 14 has the largest width at the motor portion 72, and the motor portion 72 has an outer diameter Dp.
Is a cylindrical shape having. Therefore, the maximum outer diameter of the fuel pump 14 is equal to the outer diameter Dp of the motor portion 72. The length of the fuel pump 14 with respect to the axial direction of the motor portion 72 is Lp.

The fuel filter 15 has a function of removing foreign matters in the fuel in the sub-tank 8 and filtering it. One end of the fuel filter 15 is attached to the bottom of the fuel pump 14 by a clip 56 press-fitted from below the fuel pump 14. There is. As a result, the filtered fuel can flow into the fuel pump 14 from the suction port (not shown) at the bottom of the fuel pump 14. The other end of the fuel filter 15 extends radially outward of the fuel pump 14 in a direction substantially perpendicular to the axial direction of the fuel pump 14. As described above, the resin pump case 1 is used as the pump unit 140 in which the fuel pump 15 is assembled to the fuel pump 14.
A fuel pump 14 is housed inside the unit 6.

Pump Case 16 As shown in FIGS. 2 to 5, the pump case 16 for accommodating the fuel pump 14 comprises a cylindrical body 34 having a bottom and an opening 34a at the upper end. The inner diameter of the cylindrical body 34 is slightly larger than the maximum outer diameter Dp of the fuel pump 14. A discharge port 36 for discharging the fuel vapor is formed on the outer peripheral wall surface near the lower end of the cylindrical body 34. Flange 24 of cylinder 34
A side end portion is a suspension fixing portion 82, and a claw portion 27, 2 as a snap fit portion for fixing the pump case 16 to a flange is provided on an outer peripheral portion of the suspension fixing portion 82.
8, 29 are provided. The lower ends of the claws 27, 28, 29 coincide with the lower ends of the suspension fixing parts 82. At the time of assembling, the claw portions 27, 28, 29 are fixed to the fitting groove of the flange 24 by snap fit, so that the pump case 16 is suspended and fixed to the flange 24. The flange 24 abuts on the upper end of the protrusion 161 provided on the pump case 16, whereby the flange 2 of the pump case 16 is
The height from 4 is specified. Further, in the cylindrical body 34, a recess 271 for facilitating the removal of the flange 24 from the pump case 16 following the lower portions of the claw portions 27 and 28,
281 is formed.

Below the suspension fixing portion 82 of the cylindrical body 34 is a pump mounting portion 81, and an opening 340 is provided on the side surface of the pump mounting portion 81. This opening 340
Extends from the arcuate notch 341 a provided on the outer periphery of the bottom surface 341 of the cylindrical body 34 to the lower end of the suspension fixing portion 82. Therefore, the upper end of the opening 340 has the claws 27, 2
It has the same height as the lower ends of 8 and 29. When the tubular body 34 is cut in a cross section perpendicular to its axis, the cross section of the pump attachment portion 81 in which the opening 340 is formed is C-shaped, and the cross section of the suspension fixing portion 82 is ring-shaped. The opening 340 has a substantially rectangular shape when viewed from the radial direction of the tubular body 34, its width Dh is slightly smaller than the maximum outer diameter Dp of the fuel pump 14, and its height Lh is the axial length of the fuel pump 14. It is slightly smaller than Lp. In one embodiment of the present invention, specifically, Dh = 35 mm and Dp = 38 mm.

As shown in FIG. 8, a rubber pump cushion 51 is attached to the bottom of the cylindrical body 34 prior to the assembly of the pump unit 140. The pump cushion 51 includes the inner bottom portion of the pump case 16 and the fuel pump 1.
4 functions as a pump seat. As shown in FIGS. 2 to 5, the sender gauge mounting portion 86 is provided so as to project radially outward from the cylindrical body 34. The sender gauge mounting portion 86 includes positioning projections 861 and 862 for fitting and positioning the metal plate 42 as a mounting bracket of the sender gauge 41 shown in FIG. 8, and guide portions 863 for guiding both sides of the metal plate 42 in the insertion direction. , 864. The positioning protrusions 861 and 862 are formed in a convex shape on the outer circumference in the extending direction of the tubular body 34, and L-shaped guide portions 863 and 864 project on both sides of a portion wider than this. Positioning convex portions 861 and 86 of the guide portions 863 and 864
Contact surfaces 863a and 864a, which serve as sliding surfaces when the metal plate 42 is inserted, are formed on the surface facing the surface 2. Here, in order to shorten the slide length when the sender gauge is attached / detached, a notch 86 is provided at the upper ends of the guide portions 863 and 864.
3b, 864b are provided and contact surfaces 863a, 86
4a is not formed. Positioning projections 862, 861
A snap fit portion 865 that can be fitted into the hole of the metal plate for mounting the sender gauge is formed on the lower end side of the, and a locking portion 866 that is the assembly end position of the metal plate 42 is convex on the lower end side. Is formed in. The positioning protrusions 861 and 862 and the guide portions 863 and 864
Is provided with a gradient so that it can be molded with a resin.

Sender Gauge (Liquid Level Gauge) 41 As shown in FIG. 8, the sender gauge 41 functions as a liquid level gauge for detecting the liquid surface of the fuel in the tank from the electric resistance value, and the thermistor 48 functions as a remaining amount warning lamp. . A metal plate 42 that functions as a mounting bracket to the pump side flange is attached to the sender gauge 41. At the lower end of the metal plate 42, an unillustrated disengagement prevention hole that fits with the snap fit portion 865 of the sender gauge mounting portion 86 is formed. One end of an arm 47 is swingably attached to the metal plate 42.
A float 46 that can float on the liquid surface is rotatably attached to the other end of 7. Further, on the side of the metal plate 42, a thermistor 48 that functions as a remaining amount warning lamp for displaying the remaining amount of fuel in the tank is provided. This sender gauge 41
8 is attached to the pump case 16 by inserting the metal plate 42 into the sender gauge attachment portion 86 from above the pump case 16 as shown in FIG.

Next, a method of assembling the pump unit 140 to the pump case 16 will be described with reference to FIGS.
This will be described with reference to (A) and (B) and FIGS. Here, although omitted in FIGS. 6 and 7, a fuel filter 15 is attached to the lower end of the fuel pump 14 as in FIGS. 1A and 1B. That is, the fuel pump 14 is assembled in the pump case 16 as the pump unit 140 having the fuel pump 15 fixed to the lower end thereof.

First, as shown in FIGS. 6A and 6B, the discharge portion 73 side of the fuel pump 14 is inserted into the cylindrical body 34 through the hole 350 formed by the opening 340. Then, as shown in FIGS. 7A and 7B, the opening 3 at the upper end of the pump case 16 is passed through the annular suspension fixing portion 82.
The fuel pump 14 is moved in a direction in which the discharge portion 73 is taken out of the 4a. As this operation progresses, the motor portion 72 and the pump portion 71 of the fuel pump 14 following the discharge portion 73 are inserted into the pump case 16 through the hole 350. At this time, as described above, the width Dh of the opening 340 is
(= 35 mm) is the maximum outer diameter Dp (= 3 of the fuel pump 14
8 mm), and since the pump case 16 is made of elastically deformable resin, the opening 340 is expanded in the width direction by the motor portion 17 as shown in FIG. 7B. As shown in FIGS. 1A and 1B, the fuel pump 1
When the portion up to the lower end of 4 is inserted into the pump case 16, the elasticity of the pump case 16 causes the opening 340 to return to the width Dh which is the shape when an external force is not applied. This prevents the fuel pump 14 from falling out of the hole 350 after assembly. In addition, as described above, the fuel pump 1
The axial length Lp of 4 is slightly smaller than the height Lh of the opening 340 also prevents the fuel pump 14 from falling out of the hole 350 after assembly.

When the pump unit 140 is replaced, the fuel filter 15 fixed to the lower portion of the fuel pump 14 is strongly pulled outward in the radial direction of the pump case 16 so that the hole 35
The fuel pump 14 can be removed through 0. The width Dh of the opening 340 varies depending on the maximum outer diameter Dp of the fuel pump 14, the material of the pump case 16, the plate thickness of the pump case 16, and the like, but the force required for attaching and detaching the fuel pump 14 is desired to exceed 0. Set it to an appropriate value. For example, when the maximum outer diameter Dp of the fuel pump is 38 mm, the material of the pump case is polyacetal having a plate thickness of 2.6 mm (Test Example 1) and the case where it is polyacetal containing carbon having a plate thickness of 2.1 mm (Test Example) Regarding 2), the relationship between the width Dh of the opening and the insertion load of the fuel pump is shown in FIG. In Test Example 1, the width Dh of the opening is 30.
When it was less than mm, it was impossible to insert the fuel pump through the hole formed by the opening. Further, in Test Example 2, when the width Dh of the opening was 25 mm or less, it was impossible to insert the fuel pump through the hole formed by the opening. Since the maximum outer diameter Dp of the fuel pump is 38 mm, the insertion load becomes 0 when the opening width Dh is 38 mm or more. Therefore, it is appropriate that 30 mm <opening width Dh <38 mm under the conditions of Test Example 1 and 25 mm <opening width Dh <38 mm under the conditions of Test Example 2. Particularly, in one embodiment of the present invention, Dh
Since the insertion load is about 35 mm, the insertion load is about 2 Kgf, which is convenient because the insertion load allows the fuel pump to be easily attached and detached by human hands.

According to one embodiment of the present invention, the fuel pump 1
4 is attached to and detached from the pump case 16 by a hole 350 formed by an opening 340 provided on the side surface of the pump case 16.
Is done through Therefore, since it is not necessary to pass the fuel filter 15 through the pump case 16, even when the width of the fuel filter 15 is larger than the inner diameter of the pump case 16, the pump unit in which the fuel filter 15 is fixed to the fuel pump 14 is installed. In the state of 140, the fuel pump 14 and the pump case 16 can be attached and detached. Therefore, unlike the comparative example in which the fuel pump is inserted from the lower end opening of the pump case and then the bracket is attached to the lower end opening, it is not necessary to use the bracket, so that the number of parts and the number of assembling steps are reduced, and the fuel consumption is reduced. The positional accuracy of the pump is improved.

Since the fuel filter 15 is press-fitted and fixed to the fuel pump 14 in advance, it has an effect of preventing foreign matter from entering the fuel pump 14 through the suction port of the fuel pump 14 at the time of assembling, and the pump unit. After confirming the performance in the state of 140, the fuel pump 14 can be assembled to the pump case 16. Fuel pump 14
Can be removed from the pump case 16 as the pump unit 140 without separating the fuel pump 14 and the fuel filter 15, so that the fuel pump 14 and the fuel filter 15 can be easily replaced.

Since the suspension fixing portion 82 is not formed with the opening 340, the suspension fixing portion 82 is connected in a tubular shape without a break. As a result, the suspension fixing portion 82 is less likely to be deformed toward the inner diameter side due to heat or the passage of time, so that the snap-fitting claw portions 27, 28, and 29 are formed in the flange 2.
It is prevented from coming off from the fitting groove of No. 4. Further, since the upper end of the opening 340 and the lower ends of the claws 27, 28, 29 are at the same height, the parting line of the molding die of the pump case 16 is aligned, so that the die structure can be simplified.

Since the width Dh of the opening 340 is smaller than the maximum outer diameter Dp of the fuel pump 14, the fuel pump 14
Is inserted into the pump case 16 while expanding the opening 340 in the width direction by the motor portion 17. As a result, it is possible to prevent the fuel pump 14 from falling out of the hole 350 after the assembling without providing any special fixing means. Further, the axial length Lp of the fuel pump 14 being smaller than the height Lh of the opening 340 also prevents the fuel pump 14 from falling out of the hole 350 after assembly.

In the above embodiment, the width Dh of the opening 340 is smaller than the maximum outer diameter Dp of the fuel pump 14,
Also, the case where the height Lh of the opening 340 is smaller than the axial length Lp of the fuel pump 14 has been described, but when the width Dh of the opening is smaller than the maximum outer diameter Dp of the fuel pump, the height of the opening is small. Lh is the axial length Lp of the fuel pump 14.
It may be larger than. Similarly, when the height Lh of the opening is smaller than the axial length Lp of the fuel pump 14, the width Dh of the opening may be larger than the maximum outer diameter Dp of the fuel pump. Also in these cases, there is an effect of preventing the fuel pump from dropping out from the hole formed by the opening after the assembling.

In the above-described embodiment, the case where the fuel pump 14 is inserted into the pump case 16 while the opening 340 is expanded in the width direction by the motor portion 17 has been described. It is also possible to insert the fuel pump into the pump case in a state in which the pump case is bent so as to be expanded to.

[Brief description of drawings]

1A and 1B show a pump case and a pump unit of an in-tank fuel pump device according to an embodiment of the present invention, FIG. 1A being a side view and FIG.

FIG. 2 is a plan view showing a pump case of an in-tank fuel pump device according to an embodiment of the present invention.

FIG. 3 is a view in the direction of the arrow III in FIG. 2;

FIG. 4 is a view in the direction of arrow IV in FIG. 3;

5 is a view from the direction of the arrow V in FIG.

6A and 6B show a method of assembling a pump unit to a pump case in an in-tank fuel pump device according to an embodiment of the present invention, where FIG. 6A is a side view and FIG. Is.

FIG. 7 shows a method of assembling a pump unit into a pump case in an in-tank fuel pump device according to an embodiment of the present invention, (A) is a side view, and (B) is its VII.
It is a direction arrow view.

FIG. 8 is an exploded view showing an in-tank fuel pump device according to an embodiment of the present invention.

FIG. 9 is a side view showing an in-tank fuel pump device according to an embodiment of the present invention.

FIG. 10 is a cross-sectional view showing a state where an in-tank fuel pump device according to an embodiment of the present invention is installed in a fuel tank.

FIG. 11 is a characteristic diagram showing the relationship between the width of the opening of the pump case and the fuel pump insertion load in the in-tank fuel pump device according to the embodiment of the present invention.

FIG. 12 is a partial cross-sectional view showing a comparative example in which a pump case is composed of a cylindrical case and a bracket.

[Explanation of symbols]

 1 Fuel Tank 8 Sub-Tank 14 Fuel Pump 15 Fuel Filter 16 Pump Case 24 Flange 27, 28, 29 Claw (Snap Fit) 34 Cylinder 41 Sender Gauge 42 Metal Plate 51 Pump Cushion 71 Pump 72 Motor Unit 73 Discharge 81 Mounting part 82 Suspended fixing part (end part on flange side) 86 Sender gauge mounting part 140 Pump unit 340 Opening part 350 Hole

Claims (5)

[Claims] 1. A fuel pump provided in a fuel tank for pumping fuel in the fuel tank, and a fuel filter attached to a suction port of the fuel pump and extending in a direction substantially perpendicular to an axial direction of the fuel pump. , A substantially rectangular opening having a width smaller than the maximum width of the fuel pump and / or a height smaller than the axial length of the fuel pump on the outer peripheral surface, and the width and / or width of the opening due to elastic deformation Or a bottomed cylindrical pump case, the height of which can be changed and the fuel pump can be inserted into the fuel tank through a hole formed by the opening, and which is connected to the pump case and fixed to the fuel tank. An in-tank type fuel pump device, comprising: 2. The in-tank fuel pump device according to claim 1, wherein a width of the opening is smaller than a maximum width of the fuel pump. 3. The height of the opening is smaller than the axial length of the fuel pump.
The in-tank type fuel pump device as described in the above. 4. The in-tank fuel pump apparatus according to claim 1, 2 or 3, wherein the pump case is made of resin. 5. The pump case has a snap fit portion for positioning and fixing the pump case to the flange on the outer peripheral side surface of the flange side end portion, and the flange side end portion is connected in a ring shape. The in-tank fuel pump device according to claim 4.