JP7354052B2 - fuel supply device - Google Patents

Description

The technology disclosed herein relates to a fuel supply device. Specifically, the present invention relates to a fuel supply device that supplies fuel in a fuel tank to an internal combustion engine.

Conventionally, there is a fuel supply device described in Patent Document 1, for example. The fuel supply device includes a fuel pump, a passage forming member, and a pulsation damper. A fuel pump is located within the fuel tank. The passage forming member has a fuel passage through which fuel discharged from the fuel pump flows, and a damper chamber communicating with the fuel passage. A pulsation damper is installed in the damper chamber to suppress fuel pressure pulsations that occur in the fuel passage due to backflow of fuel, and to reduce vibration and noise.

Japanese Patent Application Publication No. 2003-49732

According to the conventional fuel supply device, it is necessary to include a pulsation damper, which increases the number of parts and the number of assembly steps, leading to an increase in cost.

The problem to be solved by the technology disclosed in this specification is to reduce the number of parts and assembly man-hours, and reduce costs.

In order to solve the above problems, the technology disclosed in this specification takes the following measures.

The first means includes a fuel pump disposed in a fuel tank, a cylindrical pump accommodating portion housing the fuel pump, and a passage forming portion forming a fuel passage through which fuel discharged from the fuel pump flows. a pump case having a pump case, the pump case having a volume chamber forming part forming a variable volume chamber communicating with the fuel passage, the volume chamber forming part comprising: The fuel supply device has a deformable wall portion that is elastically deformed, and the volume of the variable volume chamber is changed by elastically deforming the deformable wall portion in accordance with the fuel pressure of the fuel passage.

According to the first means, the volume of the variable volume chamber changes by elastically deforming the deformable wall portion of the volume chamber forming portion of the pump case in response to fuel pressure pulsations occurring in the fuel passage due to backflow of fuel. Thereby, fuel pressure pulsations can be suppressed and vibrations and noise can be reduced without requiring a pulsation damper. Therefore, by omitting the pulsation damper, the number of parts and assembly man-hours can be reduced, and costs can be reduced.

A second means is the fuel supply device of the first means, wherein the volume chamber forming part has a cylindrical wall part, and the pump housing part and the cylindrical wall part are different from each other. , the fuel supply devices are arranged side by side so as not to overlap each other in the axial direction.

According to the second means, it becomes possible to easily integrally mold the pump accommodating portion and the cylindrical wall portion of the volume chamber forming portion with resin by die cutting in the axial direction. Moreover, the axial length can be shortened compared to the case where the pump accommodating part and the cylindrical wall part of the volume chamber forming part are arranged so as to overlap in the axial direction.

The third means is the fuel supply device of the first or second means, and includes a bag-shaped filter member for filtering the fuel sucked into the fuel pump, and the pump case includes the filter member. This is a fuel supply device in which a fuel storage section that forms a fuel storage chamber on the upper surface side of the fuel storage section is integrally molded.

According to the third means, the number of parts and the number of assembly steps can be reduced compared to the case where the pump case and the fuel storage section are formed separately.

A fourth means is a fuel supply device according to any one of the first to third means, wherein a communication port between the fuel passage and the variable volume chamber is provided with a throttle for reducing a passage cross-sectional area of the communication port. It is a fuel supply device in which a section is provided.

According to the fourth means, it is possible to suppress rapid inflow of fuel from the fuel passage into the variable volume chamber by the throttle portion, and to suppress rapid elastic deformation of the deformable wall portion of the volume chamber forming portion.

According to the technology disclosed in this specification, by omitting the pulsation damper, the number of parts and assembly man-hours can be reduced, and costs can be reduced.

1 is a perspective view showing a fuel supply device according to a first embodiment. It is a top view showing a fuel supply device. 3 is a sectional view taken along the line III-III in FIG. 2. FIG. FIG. 3 is an exploded perspective view of the pump case. It is a top view which shows a pump case main body. 6 is a sectional view taken along the line VI-VI in FIG. 5. FIG. 6 is a sectional view taken along the line VII-VII in FIG. 5. FIG. FIG. 7 is a plan view showing a pump case main body according to a second embodiment.

Hereinafter, embodiments for implementing the technology disclosed in this specification will be described using the drawings.

[Embodiment 1]
The fuel supply device according to this embodiment supplies liquid fuel in a fuel tank mounted on a vehicle such as an automobile to an internal combustion engine. 1 is a perspective view showing the fuel supply device, FIG. 2 is a plan view thereof, and FIG. 3 is a sectional view taken along the line III--III in FIG. 2. Determine the orientation of the fuel supply system as shown by the arrow in the figure. Further, the vertical direction corresponds to the gravitational direction, so-called vertical direction, when the fuel tank is mounted on a fuel tank of a vehicle. Moreover, the front, rear, left, and right directions are not specified.

(Fuel supply device)
As shown in FIG. 3, the fuel supply device 20 includes a pump case 21, a fuel pump 100, a pressure regulator 110, a fuel filter 120, and a filter cover 130 that are modularized. The fuel supply device 20 is inserted into the tank through an opening formed in the upper surface of the fuel tank 10 and installed on the bottom wall 11 . The fuel tank 10 is a hollow container in which gasoline as a liquid fuel is stored.

(Pump case 21)
FIG. 4 is an exploded perspective view of the pump case. As shown in FIG. 4, the pump case 21 includes a pump case body 22 having an opening on the top surface, and a cap 23 that closes the opening on the top surface. The pump case body 22 and the cap 23 are made of resin.

(Pump case body 22)
5 is a plan view showing the pump case body, FIG. 6 is a sectional view taken along the line VI-VI in FIG. 5, and FIG. 7 is a sectional view taken along the line VII-VII in FIG. As shown in FIG. 6, the pump case main body 22 includes a pump housing section 30, a fuel storage section 40, a regulator mounting section 50, and a passage forming section 60.

The pump accommodating portion 30 is formed into a cylindrical shape with an open bottom. The pump accommodating portion 30 has a cylindrical tube portion 31 and an upper surface portion 32 that closes the upper surface of the tube portion 31 . A rectangular opening hole 33 is formed at the upper end of the pump accommodating portion 30 and extends from the upper surface portion 32 to the right rear portion of the cylindrical portion 31 (see FIG. 5).

The fuel storage part 40 is formed in a cylindrical shape surrounding the lower part of the pump housing part 30 with a predetermined gap therebetween. As shown in FIG. 5, the pump accommodating portion 30 is disposed at a position to the right of the fuel storage portion 40 in a plan view of the pump case body 22. The fuel storage section 40 has a flange section 42 that projects radially inward from the upper end. The flange portion 42 is connected to a front side portion and a rear side portion of the cylindrical portion 31 of the pump housing portion 30 at the vertical center portion thereof. As shown in FIG. 3, the upper part of the pump accommodating part 30 projects upward from the flange part 42. Further, the lower end of the cylindrical portion 31 of the fuel storage portion 40 is arranged at a lower position than the lower end of the pump accommodating portion 30.

As shown in FIG. 6, the regulator mounting portion 50 is formed into a cylindrical shape with an open bottom. The regulator mounting portion 50 has a cylindrical tube portion 51 and an upper surface portion 52 that closes the upper surface of the tube portion 51. The upper surface portion 52 of the regulator attachment portion 50 is connected to the vertical center portion of the pump housing portion 30 and the flange portion 42 of the fuel storage portion 40 . As shown in FIG. 5 , the regulator mounting portion 50 is disposed on the left side of the pump accommodating portion 30 in a plan view of the pump case body 22 . Further, as shown in FIG. 3, the lower end of the cylindrical portion 51 of the regulator mounting portion 50 is disposed at a higher position than the lower end of the pump accommodating portion 30.

As shown in FIG. 6, the passage forming part 60 has an inlet cylinder part 61, a branch cylinder part 63, and an outlet port 65. The inlet cylinder part 61 is arranged at the left end of the upper surface part 32 of the pump housing part 30. The inlet cylinder portion 61 is formed into a cylindrical shape extending in the vertical direction.

The branch cylinder part 63 is formed in a cylindrical shape extending in the vertical direction along the upper left side of the pump housing part 30 . The upper end of the branch tube 63 is connected to the left side of the inlet tube 61 . A lower end portion of the branch cylinder portion 63 is connected to a right end portion of the upper surface portion 52 of the regulator mounting portion 50. The internal space of the branch cylinder part 63 is communicated with the internal space of the regulator mounting part 50.

A U-shaped communication groove 64 having an open upper surface is opened in the partition wall between the inlet cylinder part 61 and the branch cylinder part 63. The internal space of the inlet cylinder part 61 and the internal space of the branch cylinder part 63 are communicated with each other by the communication groove 64 .

The outlet port 65 projects in a cylindrical shape from the left side surface of the branched cylinder portion 63 (see FIG. 5). The interior space of the outlet port 65 is communicated with the interior space of the branch cylinder portion 63 and the outside. A fuel passage 67 is formed by the internal space of the inlet cylinder part 61, the internal space of the branch cylinder part 63, and the internal space of the outlet port 65.

A volume chamber forming portion 70 is formed on the front side of the branched cylinder portion 63 . The volume chamber forming part 70 has a C-shaped cylindrical peripheral wall part 71 and a lower wall part 72 that closes a lower opening of the peripheral wall part 71 (see FIG. 7). Both ends of the peripheral wall portion 71 are connected to the front side portion of the branch tube portion 63 (see FIG. 5). The peripheral wall portion 71 has a length (height) that is approximately the same as the length (height) of the branch tube portion 63 in the vertical direction. The peripheral wall portion 71 and the lower wall portion 72 are formed to be elastically deformable in the wall thickness direction, so-called bending deformation. The peripheral wall portion 71 and the lower wall portion 72 correspond to the “deformed wall portion” in this specification.

A communication port 74 is opened in the front side of the branch cylinder part 63 to communicate the internal space of the branch cylinder part 63, that is, the fuel passage 67, and the internal space of the volume chamber forming part 70. The internal space of the volume chamber forming portion 70 is a variable volume chamber 76 that communicates with the fuel passage 67 via a communication port 74 .

As shown in FIG. 5, in a plan view of the pump case body 22, the volume chamber forming portion 70 is formed in a rounded L-shape with a front end wrapping around the front side of the pump accommodating portion 30. Further, the volume chamber forming portion 70 is arranged so as to fit within the outer shape of the flange portion 42 of the fuel storage portion 40.

The pump accommodating portion 30 and the volume chamber forming portion 70 including the peripheral wall portion 71 and the lower wall portion 72 are arranged side by side so as not to overlap each other in the axial direction (front and back directions in the paper plane in FIG. 5). The peripheral wall portion 71 corresponds to a “cylindrical wall portion” in this specification.

The upper end surface of the inlet cylinder part 61, the upper end surface of the branch cylinder part 63, and the upper end surface of the volume chamber forming part 70 form the joined surface 22a. The surface to be joined 22 a is formed in an annular shape surrounding the fuel passage 67 and the upper opening of the variable volume chamber 76 . The pump case main body 22 is an integrally molded product made of resin.

(Cap 23)
As shown in FIG. 4, the cap 23 is formed into a dome shape. A joint surface 23a corresponding to the joint surface 22a of the pump case body 22 is formed on the outer peripheral portion of the lower surface of the cap 23. The joint surface 23a of the cap 23 is joined to the joint surface 22a of the pump case body 22 by welding or the like (see FIGS. 1 to 3). As a result, a pump case 21 consisting of a pump case main body 22 and a cap 23 is formed.

Since the cap 23 covers the upper surface openings of the fuel passage 67 and the variable volume chamber 76, it can be considered as the upper wall portion 23 (designated with the same reference numeral as the cap) of the passage forming portion 60 and the volume chamber forming portion 70. (See Figure 3). The upper wall portion 23 is formed to be elastically deformable in the wall thickness direction, so-called bending deformation. The upper wall portion 23 corresponds to a “deformable wall portion” in this specification.

(fuel pump 100)
As shown in FIG. 3, the fuel pump 100 has a vertical cylindrical outer shape. The fuel pump 100 is a motor-integrated in-tank electric fuel pump that includes an electric motor section and a pump section provided at the lower end of the motor section. A fuel intake port 101 is protruded from the lower end surface of the fuel pump 100. A fuel discharge port 102 protrudes from the upper end surface of the fuel pump 100. An electrical connector section 104 is formed at the upper end of the fuel pump 100.

The fuel pump 100 is housed vertically in the pump accommodating portion 30 of the pump case 21 by being inserted from below. A fuel discharge port 102 of the fuel pump 100 is connected to the inside of the inlet cylinder portion 61 of the pump case 21 . Thereby, the internal space of the fuel pump 100 and the fuel passage 67 are communicated with each other. The electrical connector section 104 of the fuel pump 100 is arranged so as to be exposed in the opening hole 33 of the pump housing section 30 (see FIG. 2).

(Pressure regulator 110)
As shown in FIG. 3, the pressure regulator 110 has a short vertical cylindrical outer shape. An annular flange 112 is formed on the outer circumferential surface of the pressure regulator 110 at the center in the vertical direction.

The upper part of the pressure regulator 110 is inserted into the regulator mounting part 50 of the pump case 21. A resin-made retaining member 115 that accommodates the lower part of the pressure regulator 110 and prevents the flange 112 from coming off is attached to the regulator attachment portion 50 by snap-fitting. The pressure regulator 110 adjusts the fuel pressure within the fuel passage 67, that is, the fuel pressure supplied to the internal combustion engine. The retaining member 115 has a fuel discharge hole 116 for discharging surplus fuel that has become surplus due to adjustment of the fuel pressure by the pressure regulator 110.

(Fuel filter 120)
As shown in FIG. 3, the fuel filter 120 includes a filter member 121 and a connecting member 122. The filter member 121 is formed into a hollow bag shape using a filter material made of a nonwoven resin fabric. The filter member 121 has a disk-shaped outer shape and horizontal upper and lower surfaces.

The connecting member 122 is arranged on the upper surface side of the filter member 121. Although not shown, an inner rib member is disposed within the filter member 121 to ensure an internal volume of the filter member 121. The connecting member 122 is coupled to the inner bone member so as to communicate between the inside and outside of the filter member 121. The connecting member 122 and the inner bone member are made of resin.

The connecting member 122 is attached to the pump accommodating portion 30 of the pump case 21 by a snap fit. Thereby, the fuel pump 100 is held within the pump accommodating portion 30. Further, by connecting the connecting member 122 to the fuel suction port 101 of the fuel pump 100, the internal space of the filter member 121 and the internal space of the fuel suction port 101 are communicated with each other.

The filter member 121 is arranged substantially horizontally so as to close the lower surface of the fuel storage section 40 of the pump case 21 . As a result, a fuel storage chamber 125 capable of storing fuel is formed between the fuel storage section 40 and the fuel filter 120. The fuel storage chamber 125 is formed on the upper surface side of the filter member 121. The fuel storage chamber 125 can store the fuel in the fuel tank 10 that flows in from the upper opening of the fuel storage section 40 and the fuel discharged (discharged) from the pressure regulator 110. Further, the filter member 121 filters fuel drawn into the fuel pump 100 from both the upper and lower sides.

(filter cover 130)
As shown in FIG. 3, the filter cover 130 is formed in the shape of a shallow circular dish with a bottom wall 131 shaped like a lattice plate. A plurality of protrusions 132 protrude discretely from the lower surface of the bottom wall 131 . Filter cover 130 is made of resin.

The filter cover 130 is attached to the fuel storage portion 40 of the pump case 21 by a snap fit so as to cover the lower surface side of the filter member 121 of the fuel filter 120. By attaching the filter cover 130 to the fuel storage section 40, the peripheral edge of the filter member 121 is sandwiched between the fuel storage section 40 and the filter cover 130 in a sealed state.

(Installation of fuel supply device 20)
The fuel supply device 20 is installed at the bottom of the fuel tank 10, that is, on the bottom wall 11. A protrusion 132 of a filter cover 130 is in contact with the bottom wall 11 . Although not shown, a fuel supply pipe connected to the internal combustion engine is connected to the outlet port 65 of the pump case 21. Further, an external connector connected to a power source, an ECU, etc. is connected to the electrical connector section 104 of the fuel pump 100.

(Operation of fuel supply device 20)
Fuel pump 100 is driven by external driving power. Then, the fuel in the fuel tank 10 and/or the fuel in the fuel storage chamber 125 is filtered by the filter member 121 of the fuel filter 120 and then sucked into the fuel pump 100 through the connecting member 122. Fuel pressurized by the fuel pump 100 is discharged into the fuel passage 67 of the pump case 21, and the pressure is regulated by the pressure regulator 110. The regulated pressurized fuel is supplied to the engine from the outlet port 65 of the pump case 21 via the fuel supply pipe. Furthermore, surplus fuel (return fuel) that has become surplus due to adjustment of the fuel pressure of the pressure regulator 110 is discharged, that is, discharged into the fuel storage chamber 125.

(Actions and effects of Embodiment 1)
According to the fuel supply device 20 of the first embodiment, the peripheral wall portion 71, the lower wall portion 72, and the upper wall of the volume chamber forming portion 70 of the pump case 21 respond to fuel pressure pulsations occurring in the fuel passage 67 due to backflow of fuel. By elastically deforming the portion 23, the volume of the variable volume chamber 76 changes (increases or decreases). Thereby, fuel pressure pulsations can be suppressed and vibrations and noise can be reduced without requiring a pulsation damper. Therefore, by omitting the pulsation damper, the number of parts and assembly man-hours can be reduced, and costs can be reduced.

Further, a pump case 21 having a volume chamber forming portion 70 is disposed within the fuel tank 10. Therefore, unlike the case where a pulsation damper is interposed in the middle of the fuel supply pipe outside the fuel tank 10, even if the volume chamber forming part 70 is damaged, fuel can be prevented from leaking outside the fuel tank 10. Can be done.

Further, the pump housing portion 30 and the cylindrical peripheral wall portion 71 of the volume chamber forming portion 70 are arranged side by side so as not to overlap each other in the axial direction. Therefore, the pump accommodating portion 30 and the peripheral wall portion 71 of the volume chamber forming portion 70 can be easily integrally molded with resin by die cutting in the axial direction. Therefore, in this embodiment, the pump case main body 22 can be easily integrally molded with resin. Moreover, the axial length can be shortened compared to the case where the pump accommodating part 30 and the peripheral wall part 71 of the volume chamber forming part 70 are arranged so as to overlap in the axial direction.

Furthermore, a fuel storage section 40 that forms a fuel storage chamber 125 on the upper surface side of a bag-shaped filter member 121 that filters fuel sucked into the fuel pump 100 is integrally formed in the pump case 21 . Therefore, compared to the case where the pump case 21 and the fuel storage section 40 are formed separately, the number of parts and the number of assembly steps can be reduced.

[Embodiment 2]
Since this embodiment is a modification of the pump case main body 22 of Embodiment 1, the modified parts will be explained, and the same parts as in Embodiment 1 will be given the same reference numerals and redundant explanation will be omitted. . FIG. 8 is a plan view showing the pump case body. As shown in FIG. 8, the communication port 74 between the fuel passage 67 of the pump case body 22 and the variable volume chamber 76 is provided with a constriction portion 80 that reduces the passage cross-sectional area of the communication port 74. The throttle portion 80 is formed in a rib shape that protrudes from the left end toward the right end of the peripheral wall portion 71 of the volume chamber forming portion 70 . The constricted portion 80 extends along the vertical direction of the left end portion of the peripheral wall portion 71 .

According to this embodiment, the throttle part 80 suppresses the sudden inflow of fuel from the fuel passage 67 into the variable volume chamber 76, and the rapid flow of fuel into the variable volume chamber 76 from the fuel passage 67 is suppressed, and the sudden flow of fuel into the variable volume chamber 76 is suppressed. It is possible to suppress elastic deformation.

[Other embodiments]
The technology disclosed in this specification is not limited to the embodiments described above, and can be implemented in various other forms. For example, in the embodiment, the peripheral wall 71, the lower wall 72, and the upper wall 23 of the volume chamber forming part 70 are made into deformed walls, but one or two of the three walls are made into deformed walls. Alternatively, at least one wall portion may be partially deformed. Further, the shape, arrangement, etc. of the volume chamber forming portion 70 may be changed. Further, the upper wall portion (cap) 23 may be provided so as to cover the fuel passage 67 and the upper surface opening of the variable volume chamber 76 separately.

10 Fuel tank 20 Fuel supply device 21 Pump case 23 Cap, upper wall portion (deformable wall portion)
30 Pump housing section 40 Fuel storage section 60 Passage forming section 67 Fuel passage 70 Volume chamber forming section 71 Peripheral wall section (deformable wall section, cylindrical wall section)
72 Lower wall part (deformed wall part)
74 Communication port 76 Variable volume chamber 80 Throttle section 100 Fuel pump 120 Fuel filter 121 Filter member 125 Fuel storage chamber

Claims (3)

a fuel pump located within the fuel tank;
a pump case having a cylindrical pump accommodating portion for accommodating the fuel pump, and a passage forming portion forming a fuel passage through which fuel discharged from the fuel pump flows;
A fuel supply device comprising:
A volume chamber forming portion forming a variable volume chamber communicating with the fuel passage is formed in the pump case,
The volume chamber forming part has a deformable wall part that is elastically deformed,
The volume of the variable volume chamber changes by elastically deforming the deformable wall portion in accordance with the fuel pressure of the fuel passage,
The volume chamber forming part has a cylindrical wall part,
In the fuel supply device, the pump housing portion and the cylindrical wall portion are arranged side by side so as not to overlap each other in the axial direction . The fuel supply device according to claim 1 ,
It includes a bag-shaped filter member that filters fuel sucked into the fuel pump,
A fuel supply device, wherein the pump case is integrally molded with a fuel storage portion that forms a fuel storage chamber on the upper surface side of the filter member. The fuel supply device according to claim 1 or 2 ,
A fuel supply device, wherein a communication port between the fuel passage and the variable volume chamber is provided with a constriction portion that reduces a passage cross-sectional area of the communication port.

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