JP6787843B2 - Fuel filter and fuel pump module - Google Patents

Description

The present invention relates to a fuel filter for a fuel pump mounted on a vehicle and sucking liquid fuel from a fuel tank and pumping it toward an internal combustion engine, and a fuel pump module using the fuel filter.

Conventionally, an in-line type fuel supply device in which a fuel pump and a fuel filter are arranged outside the fuel tank and the fuel in the fuel tank is boosted by the fuel pump and supplied to the fuel injection valve has been known (for example, a patent). Reference 1).
In this fuel supply device, a filtration type primary filter (fuel filter) is arranged on the upstream side of the fuel pump.

In this type of filtration type fuel filter, the fuel is filtered by allowing the fuel to permeate from the outer peripheral side to the inner peripheral side of the cylindrical filter element housed in the filter case. Then, the fuel after filtration is discharged to the outside from the outlet connected to the space on the inner peripheral side of the filter element.

Japanese Unexamined Patent Publication No. 2006-257979

By the way, when a fuel filter using this type of filtration type filter cartridge is installed in a posture in which the axis is oriented in the horizontal direction, the inside of the filter case is sufficient depending on how the fuel intake pipe is joined to the filter case. It turns out that it may not be filled with fuel. For example, at high temperatures, a large amount of bubbles are generated from the fuel, but if these bubbles tend to stay in the filter case and the discharge to the fuel tank side cannot keep up, as a result, in the filter case. Gas-liquid exchangeability may deteriorate. In such a case, it becomes difficult to introduce the fuel into the filter case, and the fuel supply to the internal combustion engine side may not catch up, leading to a decrease in fuel pressure.

Therefore, the present invention has been made in view of the above-mentioned circumstances, and smoothly discharges air bubbles generated in the filter case to the fuel tank side and inflows of fuel from the fuel tank into the filter case. It is an object of the present invention to provide a fuel filter capable of improving gas-liquid exchangeability and a fuel pump module using the fuel filter.

In order to solve the above problems, the fuel filter according to the present invention includes a bottomed tubular filter unit case having a tubular peripheral wall and an end wall that closes one end opening of the tubular peripheral wall, and an axial direction of the filter unit case. A fuel suction pipe that has a tubular shape extending in a direction intersecting with the filter unit case and whose base end side is joined to the outer surface portion of the tubular peripheral wall of the filter unit case, and inside the filter unit case, inside the tubular peripheral wall. A filter cartridge housed concentrically with the peripheral surface is provided, and the internal passage of the fuel suction pipe intersects the inner peripheral surface of the fuel suction pipe with the inner peripheral surface of the tubular peripheral wall of the filter unit case. It communicates with the internal space of the filter unit case through a communication port surrounded by a communication line, and a part of the internal passage is inside the filter unit case when viewed from the extending direction of the fuel suction pipe. The inner peripheral surface of the tubular peripheral wall of the filter unit case is a first cylindrical inner peripheral surface having a radius R, and the inner peripheral surface of the fuel suction pipe has a radius so as to project outward from the space. The inner peripheral surface of the second cylinder of r is defined as the distance between the first central axis of the inner peripheral surface of the first cylinder and the second central axis of the inner peripheral surface of the second cylinder of the fuel suction pipe. Let Z1 be the value obtained by subtracting the height of the end end side of the internal passage of the fuel suction pipe from the height of the central axis of the filter unit case, and the radius R, the radius r, and the distance. D and the value Z1 are
2r <R
Rr <D ≤ R
0 <Z1 <R
It is characterized in that it is set to satisfy .

With this configuration, for example, when the filter case is arranged so that the axial direction of the filter case is along the horizontal direction and the tip opening of the fuel suction pipe faces upward in the gravity direction, the filter case Since the air bubbles are about to be discharged toward the tip opening through the fuel suction pipe through the shortest path, half of the internal passages of the fuel supply pipe on the filter case side are defined as a passage through which the air bubbles actively pass. can do. Further, of the internal passages of the fuel supply pipe, the half on the side opposite to the filter case side can be a passage through which fuel positively passes. Further, the opening area of the communication port between the filter case and the fuel intake pipe can be set large.
Therefore, at the communication port, it is possible to sufficiently secure a passage through which air bubbles actively pass and a passage through which fuel actively passes. As a result, the inflow of fuel from the fuel suction pipe to the filter case and the discharge of air bubbles from the filter case to the fuel suction pipe can be smoothly performed while reducing mutual interference. Even when a large amount of air bubbles are generated from the fuel, especially at a high temperature, the flow of air bubbles from the filter case to the fuel intake pipe can be smoothed. That is, the gas-liquid exchangeability can be improved. Therefore, a sufficient amount of fuel can be stored in the filter case, and it is possible to prevent the fuel supply to the pump unit from becoming insufficient.
In addition, the opening area of the communication port between the filter case and the fuel intake pipe can be set as large as possible. Therefore, it is possible to surely improve the gas-liquid exchangeability and prevent the fuel supply to the pump unit from becoming insufficient. Further, it is possible to reduce the retention of fuel and air bubbles and promote smooth gas-liquid exchange.

The fuel filter according to the present invention is characterized in that, when the fuel suction pipe is viewed from the extending direction of the fuel suction pipe, more than half of the opening area of the internal passage overlaps with the internal space of the filter case. To do.

With this configuration, the opening area of the communication port between the filter case and the fuel intake pipe can be set as large as possible. Therefore, it is possible to surely improve the gas-liquid exchangeability and prevent the fuel supply to the pump unit from becoming insufficient.

The fuel filter according to the present invention is characterized in that the base end side of the fuel suction pipe is joined to a corner portion from the outer surface portion of the tubular peripheral wall of the filter case to the end wall.

With this configuration, half of the internal passage of the fuel supply pipe on the filter case side can be a passage through which air bubbles actively pass. Further, of the internal passages of the fuel supply pipe, the half on the side opposite to the filter case side can be a passage through which fuel positively passes. Therefore, the bubbles generated in the filter case can be smoothly discharged and the fuel can be smoothly flowed in from the fuel intake pipe, and the gas-liquid exchangeability can be further improved.

In the fuel filter according to the present invention, the filter cartridge includes a tubular filter element that filters fuel by allowing fuel to permeate from the outer peripheral side to the inner peripheral side, and one end opening of the filter element. It has a rear surface plate arranged near the end wall of the filter case and a fuel outlet that closes the other end opening of the filter element and guides fuel that has permeated through the space on the inner peripheral side of the filter element to the outside in the center. When the fuel suction pipe is viewed from the extending direction of the fuel suction pipe, the internal passage and the rear surface plate are overlapped with each other.

With this configuration, the space between the rear surface plate and the end wall of the filter case can be narrowed, and it is possible to make it difficult for air bubbles to be discharged from this space. As a result, it becomes easy to introduce fuel between the rear surface plate and the end wall of the filter case. Therefore, the bubbles generated in the filter case can be smoothly discharged and the fuel can be smoothly flowed in from the fuel intake pipe, and the gas-liquid exchangeability can be further improved.

The fuel pump module according to the present invention includes the fuel filter described above and a pump unit that sucks in liquid fuel from the fuel tank and discharges it to the outside, and the fuel filter is introduced from the fuel tank. The liquid fuel is filtered and led out to the pump unit.

With this configuration, the bubbles generated in the filter case can be smoothly discharged to the fuel tank side and the fuel can flow in from the fuel tank into the filter case smoothly, and gas-liquid exchangeability can be improved. A fuel pump module that can be enhanced can be provided.

According to the present invention, it is possible to smoothly discharge the bubbles generated in the filter case to the fuel tank side and the inflow of fuel from the fuel tank into the filter case, thereby improving gas-liquid exchangeability. Can be done. As a result, a sufficient amount of fuel can be stored in the filter case, and it is possible to prevent the fuel supply to the pump unit from becoming insufficient.

It is external perspective view of the fuel pump module of embodiment of this invention. It is an exploded perspective view of the fuel pump module of embodiment of this invention. It is a vertical sectional view of the fuel pump module of the embodiment of this invention. It is a perspective view before coupling of the pump unit and the filter unit which constitute the fuel pump module of embodiment of this invention. It is an exploded perspective view of the filter unit (fuel filter) in embodiment of this invention. In the configuration diagram of the filter unit according to the embodiment of the present invention, (a) is a plan view seen from above vertically showing the state before inserting the filter cartridge into the filter unit case (filter case), and (b) is the filter unit case. It is a plan view seen from the vertical upper side which shows the state which inserted the filter cartridge into. In the configuration diagram of the filter unit case according to the embodiment of the present invention, (a) is a perspective view seen from the rear diagonally lower side of the filter unit case, and (b) is a front view seen from the direction of the arrow B in FIG. (C) is a rear view seen from the direction of the arrow C in the figure (a). In order to explain the proper positional relationship between the filter unit case and the fuel intake pipe in the embodiment of the present invention, a schematic plan view of a cross section cut along a horizontal plane including the central axis of the filter unit case is viewed from above vertically. (B) and (b) show the case where the fuel intake pipe is arranged within the range of the proper positional relationship, and (c) shows the case where the fuel suction pipe is arranged under the condition outside the range of the proper positional relationship. Is. In the schematic front view seen from the horizontal direction for explaining the proper dimensional relationship between the filter unit case and the fuel intake pipe in the embodiment of the present invention, (a) is provided with the fuel suction pipe in the proper dimensional relationship. In the case, (b) is a diagram showing a case where the fuel intake pipe is provided with a less preferable dimensional relationship. It is a schematic explanatory view which shows the flow of the fuel and the bubble of the filter unit in embodiment of this invention, (a) is the schematic plan view seen from the vertical upper side, (b) is the schematic front view seen from the horizontal direction.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.
FIG. 1 is an external perspective view of the fuel pump module of the embodiment. FIG. 2 is an exploded perspective view of the fuel pump module.

(Fuel pump module)
As shown in FIGS. 1 and 2, the fuel pump module 1 is a detachably connected pump unit 2 and a filter unit (corresponding to a fuel filter) 3. The filter unit 3 is located on the upstream side of the pump unit 2 in the fuel flow direction and is coupled to the pump unit 2. The liquid fuel introduced from a fuel tank (not shown) is filtered and led out to the pump unit 2.

The fuel pump module 1 is arranged outside a fuel tank (not shown) of a saddle-type vehicle such as a motorcycle, and is used for pumping liquid fuel in the fuel tank toward an internal combustion engine (not shown). Applies. Of course, it may be mounted on other vehicles such as automobiles. The fuel pump module 1 has a pump unit 2 and a filter unit 3 detachably connected to each other. As a result, the filter unit 3 can be easily removed from the pump unit 2. That is, the filter cartridge 60 (described later) in the filter unit 3 can be easily replaced, and maintenance can be easily performed.

(About direction)
Hereinafter, the upper side in the vertical direction is simply referred to as the upper side, and the lower side in the vertical direction is simply referred to as the lower side. Further, the direction along the central axis of the fuel pump module 1 (corresponding to the central axis of the suction port 11 of the pump body 10 described later and the central axis of the cylindrical pipe 50 and the cylindrical boss portion 62) is the axial direction, orthogonal to this central axis. The radial direction with respect to the central axis is called the radial direction, and the direction of orbiting around the central axis is called the circumferential direction. Regarding the distinction between the front and rear directions of the pump unit 2 and the filter unit 3, the assembling direction (matching direction) of both units 2 and 3 is set to the front, and the removing direction (counting direction) of both units 2 and 3 is set to rear. explain.

(Installation posture of fuel pump module)
The fuel pump module 1 has a substantially cylindrical shape that is long in the axial direction as a whole, and is arranged below a fuel tank (not shown) in a posture in which the central axis of the module is directed in the horizontal direction. The fuel pump module 1 includes a fuel suction pipe 4 for sucking liquid fuel from the fuel tank, a fuel discharge pipe 5 for discharging the sucked liquid fuel to the outside (toward the internal combustion engine), and returning excess fuel to the fuel tank. A fuel return pipe 6 is provided. These pipelines (fuel suction pipe 4, fuel discharge pipe 5, fuel return pipe 6) are connected to the fuel tank side and the internal combustion engine side via a hose or the like. At this time, the fuel pump module 1 is mounted below the fuel tank with the hose connection ends of the fuel suction pipe 4 and the fuel return pipe 6 facing upward in the vertical direction.

(Pumping unit)
FIG. 3 is a vertical sectional view of the fuel pump module. FIG. 4 is a perspective view of the pump unit and the filter unit constituting the fuel pump module before they are combined.
As shown in FIGS. 1 to 4, the pump unit 2 has a function of sucking liquid fuel from a fuel tank and discharging it to the outside, and has a bottomed cylindrical pump unit case 20 as an outer shell. I have. The pump unit case 20 is made of a resin molded product, and includes a cylindrical peripheral wall 21 and an end wall 23 that closes an opening at one end (rear end) of the cylindrical peripheral wall 21.

As shown in FIG. 3, a pump main body accommodating space 22 is provided inside the cylindrical peripheral wall 21. Inside the pump body accommodating space 22, a pump body 10 having a suction port 11 at one end and a discharge port 12 at the other end is accommodated. The pump body 10 sucks liquid fuel from the suction port 11 and discharges it from the discharge port 12 by driving a built-in electric motor (not shown).
Further, as shown in FIGS. 1 and 2, a connector 7 for electrically connecting the motor of the pump body 10 to an external device is provided on the outer surface of the end wall 23 of the pump unit case 20.

The above-mentioned fuel discharge pipe 5 and fuel return pipe 6 are projected outward at a position close to the end wall 23 of the cylindrical peripheral wall 21 of the pump unit case 20.
As shown in FIG. 3, inside the pump unit case 20, discharge-side internal passages 30 and 31 that sequentially communicate with each other are provided. The discharge port 12 of the pump body 10 is liquidtightly connected to the discharge side internal passage 30 located on the upstream side via an O-ring 13.

Further, the discharge side internal passage 31 located on the downstream side communicates with the internal passage 32 of the fuel discharge pipe 5 and the internal passage (not shown) of the fuel return pipe 6. The fuel discharge pipe 5 is a pipe line that discharges the fuel discharged from the pump main body 10 to the discharge side internal passages 30 and 31 to the outside. Further, the fuel return pipe 6 is a pipe line for returning the surplus fuel discharged from the pump main body 10 to the discharge side internal passages 30 and 31 to the fuel tank.

As shown in FIGS. 1 and 2, a check valve 9 is interposed inside the fuel return pipe 6. The check valve 9 is provided to prevent the backflow of fuel from the fuel tank.
Further, as shown in FIG. 3, a pressure regulator 8 is connected to the discharge side internal passage 31. The pressure regulator 8 is for ensuring a predetermined fuel pressure with respect to the fuel pumped to the internal combustion engine. The pressure regulator 8 refuels the fuel in the discharge side internal passages 30 and 31 when excess fuel pressure is generated in the discharge side internal passages 30 and 31 (when the internal fuel pressure exceeds a predetermined value). It is returned to the fuel tank through the pipe 6 and the fuel pressure of the discharged fuel is adjusted to be constant.

(Pump unit side alignment plate)
As shown in FIG. 4, the pump unit 2 is provided with a pump unit side alignment plate 40 made of a resin molded product, which is located at the opening end 25 of the cylindrical peripheral wall 21 of the pump unit case 20. The pump unit side alignment plate 40 is fixed to the pump unit case 20 in a posture perpendicular to the axial direction of the pump unit 2 so as to close the opening end 25 of the cylindrical peripheral wall 21.

The pump unit side alignment plate 40 is formed by integrally projecting a cylindrical pipe-shaped support rod 48 for supporting the pressure regulator 8 on the back surface of the disk-shaped plate main body 41. Further, in the pump unit side alignment plate 40, a slit 48a is formed in the vertical direction on the peripheral wall of the support rod 48. The pump unit side alignment plate 40 is fixed to the opening end 25 of the cylindrical peripheral wall 21 of the pump unit case 20 with the back surface of the plate body 41 having the support rod 48 facing the inside of the pump unit case 20. There is. The pump unit side mating plate 40 has a mating surface 41a for coupling with the filter unit 3 on the front surface, and the mating surface 41a is exposed to the outside and attached.

A cylindrical tube 50 protruding from the mating surface 41a toward the filter unit 3 side is provided at the center of the in-plane of the pump unit side mating plate 40. The internal through hole 50a (see FIG. 3) of the cylindrical tube 50 corresponds to the fuel intake port of the pump unit 2. The suction port 11 of the pump body 10 is fitted and connected to the end of the internal through hole 50a of the cylindrical tube 50 on the pump unit 2 side. The inner diameter of the cylindrical tube 50 is set to a diameter having sufficient gas-liquid exchangeability with respect to the discharge flow rate of the pump body 10. A step portion 51 for receiving an O-ring is provided at the base of the cylindrical tube 50. An O-ring 56 is fitted and mounted on the front side of the step portion 51 for receiving the O-ring.

(Guide convex part)
Further, on the tip end side of the cylindrical tube 50, an extension tube portion 52 that functions as a guide convex portion for centering is provided. The extension pipe portion 52 is simply a portion in which the tip of the cylindrical pipe 50 is extended to a long length with this diameter. A plurality of slits 52a extending from the tip edge toward the base of the cylindrical tube 50 are provided on the cylindrical peripheral wall of the extension tube portion 52. These slits 52a function as a communication portion that promotes the flow of liquid fuel inside and outside the extension pipe portion 52 by penetrating in the thickness direction of the peripheral wall of the cylinder.

(Immediately)
An annular abutment groove 42 is provided around the base of the cylindrical pipe 50 on the mating surface 41a of the pump unit side mating plate 40 concentrically with the cylindrical pipe 50. The inner bottom surface of the annular abutting groove 42 is a abutting surface 42a that positions the pump unit 2 and the filter unit 3 in the axial direction.

(Convex wall and recess)
Further, on the outer peripheral side of the abutting groove 42 of the mating surface 41a, a plurality of annular convex walls 43 are formed concentrically with the cylindrical tube 50 at equal intervals in the radial direction so as to surround the central portion where the cylindrical tube 50 is located. It is provided. The annular convex wall 43 has, for example, a rectangular cross section, and is formed so as to project toward the filter unit 3 side. Since a plurality of annular convex walls 43 are provided concentrically at equal intervals, an annular recess 44 is provided between the convex walls 43 adjacent to each other in the radial direction. Further, a notch 43a is provided in a part of the circumferential direction of the annular convex wall 43 located in the region below the center of the mating surface 41a with reference to the vertical direction of the installation posture of the fuel pump module 1. ing. The angular position of the notch 43a of each convex wall 43 is the same, and the presence of the notch 43a in each convex wall 43 provides a discharge groove 45 along the radial direction on the mating surface 41a.

(Filter unit)
Next, the filter unit 3 will be described.
As shown in FIGS. 2 to 4, the filter unit 3 includes a bottomed cylindrical filter unit case 80 made of a resin molded product, and a filter cartridge 60 housed inside the filter unit case 80. .. In addition, a fuel suction pipe 4 (fuel introduction port) communicating with the space before filtration of the filter cartridge 60 in the filter unit case 80, a fuel outlet port (described later) communicating with the space after filtration of the filter cartridge 60, and a pump. A filter unit side mating plate 61 having a mating surface 61a for coupling with the unit 2 is provided.
Here, the filter unit side alignment plate 61 is provided as a front plate of the filter cartridge 60, as will be described later.

FIG. 5 is an exploded perspective view of the filter unit (fuel filter). 6A and 6B are configuration diagrams of the filter unit. FIG. 6A is a plan view showing a state before the filter cartridge is inserted into the filter unit case (filter case), and FIG. 6B is a plan view seen from above vertically, and FIG. 6B is a filter in the filter unit case. It is a top view from the vertical view which shows the state which the cartridge is inserted. 7A and 7B are configuration views of the filter unit case, where FIG. 7A is a perspective view seen from the diagonally lower rear side of the filter unit case, FIG. 7B is a front view seen from the direction of the arrow B in FIG. ) Is a rear view seen from the direction of the arrow C in the figure (a).

(Filter unit case)
First, the configuration of the filter unit case (filter case) 80 will be described.
As shown in FIGS. 5 to 7 (c), the filter unit case 80 is made of, for example, resin. The filter unit case 80 has a substantially bottomed cylindrical shape, and includes a cylindrical peripheral wall (cylindrical peripheral wall) 81 having a filter cartridge accommodating space 82 inside, an end wall 83 that closes the rear end opening of the cylindrical peripheral wall 81, and the like. It is provided with a cylindrical hood portion 84 having a diameter larger than that of the cylindrical peripheral wall 81, which is extended to the front end edge of the cylindrical peripheral wall 81.
The inner peripheral surface of the cylindrical peripheral wall 81 is the inner peripheral surface of the cylinder 81a. As shown in FIGS. 1 and 3, the cylindrical hood portion 84 is provided so as to cover the front end portion of the pump unit case 20 by fitting it on the outer periphery of the front end of the cylindrical peripheral wall 21 of the pump unit case 20.

An annular plate receiving step portion 85 is provided on the inner peripheral side of the boundary between the cylindrical hood portion 84 and the cylindrical peripheral wall 81. The peripheral portion of the filter unit side alignment plate 61 provided as the front plate of the filter cartridge 60 is supported by the plate receiving step portion 85. Further, the fuel suction pipe (fuel introduction port) 4 for introducing fuel from the fuel tank is joined to a corner portion extending to both the rear end and the end wall 83 of the cylindrical peripheral wall 81.

(Arrangement and dimensions of fuel intake pipe)
Here, the arrangement and dimensions of the fuel intake pipe 4 will be described in detail.
Since the fuel pump module 1 is arranged with the axis oriented horizontally, the filter unit case 80 is similarly arranged with the axis oriented horizontally.
As shown in FIGS. 5 to 7, the fuel intake pipe 4 has a cylindrical pipe shape having an axis extending in the vertical direction. The fuel suction pipe 4 is joined to the corner portion from the outer surface portion of the cylindrical peripheral wall 81 of the filter unit case 80 to the end wall 83 with the tip opening 4b facing upward.

As a result, as shown in FIG. 5, it is surrounded by a communication line M where the inner peripheral surface 4a of the cylinder of the fuel suction pipe 4 and the inner peripheral surface 81a of the cylindrical peripheral wall 81 of the filter unit case 80 and the inner surface 83a of the end wall 83 intersect. The internal passage of the fuel suction pipe 4 is communicated with the internal space (hereinafter, simply referred to as the internal space) formed by the inner peripheral surface 81a of the cylindrical peripheral wall 81 of the filter unit case 80 through the communication port 4h. In this case, a horizontal cross section in which the internal passage of the fuel suction pipe 4 and the internal space of the filter unit case 80 overlap to the maximum, that is, a horizontal cross section including the central axis X of the filter unit case 80 as shown in FIG. 7B. In the 80X, in other words, a part of the internal passage of the fuel suction pipe 4 projects outward from the internal space of the filter unit case 80 when viewed from the extending direction of the fuel suction pipe 4. This point will be described in more detail.

FIG. 8 is a schematic plan view of a cross section cut in a horizontal plane including the central axis of the filter unit case viewed from above vertically in order to explain the proper positional relationship between the filter unit case and the fuel intake pipe. b) is a diagram showing a case where the fuel intake pipe is arranged within a range of an appropriate positional relationship, and (c) is a diagram showing a case where the fuel intake pipe is arranged under a condition outside the range of an appropriate positional relationship. ..

Here, the radius of the cylindrical inner peripheral surface 81a of the cylindrical peripheral wall 81 of the filter unit case 80 is R, the radius of the cylindrical inner peripheral surface of the fuel suction pipe 4 is r, and the cylindrical inner circumference of the cylindrical peripheral wall 81 of the filter unit case 80. When the distance between the central axis X of the surface 81a and the central axis 4x of the inner peripheral surface 4a of the cylinder of the fuel suction pipe 4 is D, the radii R, r and the distance D are the following (1) and (2), respectively. ), The values of R, r, and D are set so as to satisfy the condition of).
2r <R ... (1)
Rr <D ≤ R ... (2)

In the example shown in FIG. 8A (included in the embodiment), D <R, and a part (outer end) of the cylindrical inner peripheral surface 4a of the fuel suction pipe 4 is the cylindrical peripheral wall 81 of the filter unit case. A dimension T smaller than the radius r of the inner peripheral surface of the cylinder 4a of the fuel suction pipe 4 protrudes outside the inner peripheral surface of the cylinder 81a.

Further, in the example shown in FIG. 8B (included in the embodiment), D = R, and the outer half of the inner peripheral surface 4a of the cylinder of the fuel suction pipe 4 is the cylinder of the cylindrical peripheral wall 81 of the filter unit case. A dimension T corresponding to the radius r of the cylindrical inner peripheral surface 4a of the fuel suction pipe 4 projects outward from the inner peripheral surface 81a.

Further, in the example shown in FIG. 8C (not included in the embodiment), D> R, and more than half of the outer side of the inner peripheral surface 4a of the cylinder of the fuel suction pipe 4 is the cylindrical peripheral wall 81 of the filter unit case. The fuel suction pipe 4 projects outward from the inner peripheral surface of the cylinder 81a by a dimension T larger than the radius r of the inner peripheral surface of the cylinder 4a.

As can be seen from these illustrated examples, when the above-mentioned conditions (1) and (2) shown in FIGS. 8A and 8B are satisfied, the internal passage of the fuel suction pipe 4 and the filter unit case 80 are satisfied. The communication port 4h that communicates with the internal space of is as large as possible. In particular, in the example shown in FIG. 8A, when the fuel suction pipe 4 is viewed from the extending direction of the fuel suction pipe 4, more than half of the opening area of the inner peripheral surface of the cylinder 4a is the internal space of the filter unit case. It overlaps with. Therefore, the communication port 4h can be formed as large as possible. Further, since the undercut portion 4u as shown in FIG. 8C is not generated, it is advantageous in making the fuel and bubbles flow smoothly.

FIG. 9 is a schematic front view seen from the horizontal direction for explaining the proper dimensional relationship between the filter unit case and the fuel intake pipe, and FIG. 9A is a case where the fuel intake pipe is provided with the proper dimensional relationship. (B) is a diagram showing the case where the fuel intake pipe is provided with a less preferable dimensional relationship.

As shown in FIG. 9A, the value obtained by subtracting the height of the inner bottom surface (end portion) on the base end side of the internal passage of the fuel suction pipe 4 from the height of the central axis X of the cylindrical peripheral wall 81 of the filter unit case. When is set to Z1, the length of the base end side of the fuel intake pipe 4 is set so that the following condition (3) is satisfied.
0 <Z1 <R ... (3)

By setting in this way, the height of the inner bottom surface on the base end side of the internal passage of the fuel suction pipe 4 is larger than the height of the lowest point of the cylindrical inner peripheral surface 81a of the cylindrical peripheral wall 81 of the filter unit case. The position is higher by Z2 (> 0).

On the other hand, if Z1 is set outside the range of the above condition (3), as shown in FIG. 9B, a pool portion 4z is generated at the inner bottom portion on the base end side in the internal passage of the fuel suction pipe 4. If the volume of this portion becomes large, the fuel stays and becomes unfavorable.

(Filter cartridge)
Next, the filter cartridge will be described.
As shown in FIG. 5, the filter cartridge 60 includes a cylindrical filter element 68 that filters solid matter in the fuel by allowing liquid fuel to permeate from the outer peripheral side to the inner peripheral side, and resin molding that supports the cylindrical filter element 68. It includes a disk-shaped front plate (filter unit side mating plate 61) and a rear surface plate 67 made of a product.

The filter element (filter material) 68 is a pleated type obtained by molding a material such as filter paper having bellows-shaped folds into a cylindrical shape. The front plate is configured as a filter unit side alignment plate 61, and is fixed to the filter element 68 so as to close the front opening of the cylindrical filter element 68. The rear surface plate 67 formed in a disk shape having a smaller diameter than the front plate (filter unit side mating plate 61) is configured as a closing plate for sealing the rear surface opening of the cylindrical filter element 68, and is formed at the rear end of the filter element 68. It is stuck.

Then, as shown in FIGS. 3 and 4, in the filter cartridge 60, the peripheral edge portion of the filter unit side alignment plate 61 provided as the front plate is supported by the plate receiving step portion 85 on the inner peripheral portion of the filter unit case 80. Will be done. As a result, the mating surface 61a on the front surface of the filter unit side mating plate 61 is attached to the filter unit case 80 in a state of being exposed to the outside. That is, the filter cartridge 60 is housed inside the filter unit case 80 concentrically with the inner peripheral surface 81a of the cylindrical peripheral wall 81 of the filter unit case 80 in a posture in which the axis is directed in the horizontal direction.

Therefore, by attaching the filter cartridge 60 in this way, the space on the inner peripheral side of the filter cartridge 60 becomes the space after filtration 69 (the space on the clean side). Further, the space outside the filter cartridge 60 in the filter cartridge accommodating space 82 of the filter unit case 80 is a pre-filtering space in which fuel from the fuel tank is introduced through the fuel suction pipe (fuel introduction port) 4. Further, the filter unit side alignment plate 61 is supported inside the filter unit case 80 in a posture perpendicular to the axial direction of the filter unit 3.

Further, as shown in FIG. 2, when the filter cartridge 60 is mounted inside the filter unit case 80, the rear surface plate 67 of the filter cartridge 60 and the end wall 83 of the filter unit case 80 pass through a minute gap S. Facing in the axial direction.
Here, the fuel suction pipe 4 is joined to the corner portion from the outer surface portion of the cylindrical peripheral wall 81 of the filter unit case 80 to the end wall 83 with the tip opening 4b facing upward. When the suction pipe 4 is viewed from the extending direction of the fuel suction pipe 4, the inner peripheral surface of the cylinder 4a and the rear surface plate 67 of the filter cartridge 60 overlap each other.

(Filter unit side alignment plate)
As shown in FIG. 5, a cylindrical boss portion 62 is provided at the in-plane central portion of the filter unit side alignment plate 61. The internal through hole 70 of the cylindrical boss portion 62 is located at the center of the filter unit side alignment plate 61 as a front plate, and corresponds to the fuel outlet of the filter unit 3.
The tip end side of the cylindrical boss portion 62 is a portion to be inserted into the abutting groove 42 provided on the mating surface 41a of the pump unit side mating plate 40. The tip surface of the cylindrical boss portion 62 is a bumping surface 62a that abuts against the bumping surface 42a, which is the inner bottom surface of the bumping groove 42. The abutting surface 62a of the filter unit side mating plate 61 and the abutting surface 42a of the pump unit side mating plate 40 abut against each other, so that the mating plates 61 and 40 are positioned in the axial direction.

Further, an O-ring 56 mounted on the outer periphery of the base of the cylindrical pipe 50 of the pump unit side alignment plate 40 is inserted into the inlet side of the internal through hole 70 (fuel outlet) of the cylindrical boss portion 62 to provide sealing property. An O-ring fitting hole 73 is provided to secure the above. Further, on the inner side of the internal through hole 70 of the cylindrical boss portion 62, a guide hole portion 72 having a diameter smaller than that of the O-ring fitting hole portion 73 is provided via a step portion 71 for receiving the O-ring. .. The guide hole portion 72 serves as a guide recess for aligning the pump unit 2 and the filter unit 3 in the radial direction by inserting the extension pipe portion 52 at the tip of the cylindrical tube 50 as the guide convex portion. Fulfill.

On the outer peripheral side of the cylindrical boss portion 62 of the mating surface 61a of the filter unit side mating plate 61, a plurality of cylinder boss portions 62 are concentrically spaced in the radial direction so as to surround the central portion where the cylindrical boss portion 62 is located. An annular convex wall 63 is provided. The annular convex wall 63 of the filter unit side alignment plate 61 is provided corresponding to a position where the pump unit side alignment plate 40 fits into the annular recess 44 of the pump unit side alignment plate 40. The annular convex wall 63 of the filter unit side mating plate 61 also has, for example, a rectangular cross section similar to the annular convex wall 43 of the pump unit side mating plate 40, so as to project toward the pump unit 2 side. It is formed.

Since a plurality of annular convex walls 63 are provided concentrically at equal intervals, the annular convex walls of the pump unit side mating plate 40 are located between the convex walls 63 and the convex walls 63 that are adjacent in the radial direction. An annular recess 64 into which the 43 fits is provided. That is, the annular convex wall 43 of the pump unit side alignment plate 40 is located at a position corresponding to the annular recess 64 of the filter unit side alignment plate 61. Further, the annular convex wall 63 of the filter unit side alignment plate 61 is located at a position corresponding to the annular recess 44 of the pump unit side alignment plate 40.

Further, with reference to the vertical direction of the installation posture of the fuel pump module 1, there is a notch in a part of the circumferential direction of the annular convex wall 63 located in the region below the center of the mating surface 61a on the filter unit side. 63a is provided. The angular position of the notch 63a of each convex wall 63 is the same, and the presence of the notch 63a in each convex wall 63 provides a discharge groove 65 along the radial direction on the mating surface 61a.

As shown in FIG. 4, the angular position of the notch 43a of the annular convex wall 43 of the pump unit side mating plate 40 and the angular position of the notch 63a of the annular convex wall 63 of the filter unit side mating plate 61 are mutual. Is slightly off. As a result, when the two mating surfaces 41a and 61a are combined, the positions of the notches 43a and 63a are displaced from each other and do not overlap in the radial direction, whereby a labyrinth in the circumferential direction is formed.

Here, the abutting surface 42a of the pump unit side mating plate 40 and the abutting surface 62a of the filter unit side mating plate 61 are opposed to the inner bottom surfaces of the recesses 44, 64 of the mating surfaces 41a, 61a of the mating plates 40, 61. The top surfaces of the convex walls 63 and 43 of the above are prioritized to abut each other. By doing so, the axial positioning of the two mating plates 40 and 61 is surely performed by the abutting of the abutting surfaces 42a and 62a. At this time, the top surfaces of the convex walls 43 and 63 and the inner bottom surfaces of the recesses 64 and 44 are kept in a non-contact state with a minute gap.

(labyrinth)
Since the mating plates 40 and 61 on the pump unit 2 side and the filter unit 3 side are configured as described above, when the mating surfaces 41a and 61a of the mating plates 40 and 61 are aligned with each other, the pump unit The annular convex wall 43 on the 2 side fits into the annular recess 64 on the filter unit 3 side, and the annular convex wall 63 on the filter unit 3 side fits into the annular recess 44 on the pump unit 2 side. Maru. As a result, a labyrinth (labyrinth-like bottleneck) is formed between the mating surfaces 41a and 61a along the radial outer direction from the central portion. This labyrinth corresponds to a sealing means that exerts a sealing function to prevent foreign matter such as dust from entering from the outside.

(Joined structure)
Next, a coupling structure (coupling means) for detachably coupling the pump unit 2 and the filter unit 3 will be described. This coupling structure is provided between two cases, the pump unit case 20 and the filter unit case 80.

The pump unit 2 and the filter unit 3 can be detachably attached as a coupling structure (coupling means) between the front end portion of the cylindrical peripheral wall 21 of the pump unit case 20 and the front end portion of the cylindrical hood portion 84 of the filter unit case 80. A snap-fit type locking means (a lock convex portion 26 and a lock tongue piece 86 to be described later) and a deformation regulating means (a insertion frame 27 and an insertion tongue piece 87 to be described later) are provided.

(Locking means)
The locking means (lock convex portion 26 and lock tongue piece 86) faces the mating surfaces 41a and 61a of the pump unit side mating plate 40 and the filter unit side mating plate 61, and penetrates the inside of the cylindrical tube 50 of the pump unit 2. The pump unit 2 and the filter unit 3 are in a state where the hole 50a (fuel suction port) and the internal through hole 70 (fuel outlet) of the cylindrical boss portion 62 of the filter unit 3 are connected in a liquid-tight manner via an O-ring 56. It is for connecting and detachably.

As a locking means, a locking protrusion 26 is provided on the outer periphery of the pump unit case 20 near the front end of the cylindrical peripheral wall 21. Further, a lock tongue piece 86 is projected from the front end of the cylindrical hood portion 84 of the filter unit case 80 so as to project toward the pump unit case 20 side. A plurality of pairs (4 pairs in the illustrated example) of the lock convex portion 26 and the lock tongue piece 86 are arranged so as to correspond to each other at intervals in the circumferential direction. The lock protrusion 26 and the lock tongue piece 86 correspond to snap-fit type locking means that engage with each other by utilizing the elasticity of the material constituting the filter unit case 80.

The lock tongue piece 86 has a square window-shaped lock hole 86a as a lock recess. Further, the lock convex portion 26 with which the lock hole 86a is engaged is a convex portion having a rectangular shape in a plan view and a side view table shape, and has a front slope, a top portion, and a rear locking wall, although not described in detail. There is. The lock tongue piece 86 abuts on the front slope of the lock convex portion 26 with the axial slide operation for connecting the pump unit 2 and the filter unit 3, and the lock convex portion 26 is elastically deformed by the action of the slope. Ride on the top of the vehicle and recover from elastic deformation at the end of the ride. As a result, the lock hole 86a is engaged with the lock convex portion 26.

In the engaged state, the front inner edge of the lock hole 86a of the lock tongue piece 86 is engaged with the rear locking wall of the lock protrusion 26. The lock protrusion 26 and the lock tongue piece 86 are detachably connected by aligning the pump unit case 20 and the filter unit case 80 with each other by sliding them in the axial direction. As a result, both units 2 and 3 are locked so as not to rattle in the axial direction.

Here, as shown in FIGS. 5, 6 (a), and 6 (b), of the four pairs of lock tongue pieces 86, at least the direction in which the fuel suction pipe 4 protrudes from the filter unit case 80 is closest. The lock hole 86a of the lock tongue piece 86A facing one side in the direction is formed so that both inner side surfaces 86a1 along the axial direction are along the extending direction of the fuel suction pipe 4. As a result, when the filter unit case 80 is molded with resin, for example, the sliding direction of a part of the mold forming the fuel suction pipe 4 and the lock tongue piece 86A (mold extraction direction, see arrow Y1 in FIG. 5). It becomes possible to set the same.

(Deformation control means)
Further, an insertion frame 27 is provided on the outer periphery of the cylindrical peripheral wall 21 of the pump unit case 20 provided with the lock convex portion 26 so as to be adjacent to the peripheral direction of the lock convex portion 26. Further, an insertion tongue piece 87 is provided at the front end of the cylindrical hood portion 84 of the filter unit case 80 provided with the lock tongue piece 86 so as to be adjacent to the lock tongue piece 86 in the circumferential direction.
The insertion frame 27 and the insertion tongue piece 87 are fitted to each other by an axial slide operation for connecting the pump unit 2 and the filter unit 3, and elastic deformation of the adjacent lock tongue piece 86 in the expansion direction is performed. It constitutes a deformation control means to regulate.

The insertion tongue piece 87 extends in the sliding direction for coupling the pump unit 2 and the filter unit 3. Further, the insertion frame 27 is formed in a bag shape having an insertion slit for receiving the insertion tongue piece 87.

When the insertion tongue piece 87 is fitted into the insertion frame 27, the insertion frame 27 serves to regulate the radial outward displacement and the circumferential displacement of the insertion tongue piece 87. By restricting the displacement of the inserted tongue piece 87 in this way, it is possible to strengthen the engagement state of the adjacent lock tongue piece 86 with the lock convex portion 26.

(Guide function)
The pump unit 2 is provided with a cylindrical tube 50 having a function as a guide convex portion described above. Further, the filter unit 3 is provided with a cylindrical boss portion 62 having a function as a guide recess. These cylindrical pipes 50 and the cylindrical boss portion 62 are connected to the fuel suction port (internal through hole 50a of the cylindrical pipe 50) of the pump unit 2 and the filter unit 3 via the O-ring 56 when the two units 2 and 3 are connected. The fuel outlets (internal through holes 70 of the cylindrical boss portion 62) are fitted to each other prior to being communicated with each other. As a result, the pump unit 2 and the filter unit 3 serve as a guide function unit for centering in the radial direction.

Further, when the lock convex portion 26 and the lock tongue piece 86, which are the locking means, are mutually located at the starting points of elastic deformation for engagement, the guide hole portion 72 of the internal through hole 70 of the cylindrical boss portion 62 precedes the lock convex portion 26. The tip position of the extension tube portion 52, the position of the inlet of the guide hole portion 72, and the position of the lock convex portion 26 and the lock tongue piece 86 are set so that the extension tube portion 52 at the tip of the cylindrical tube 50 is inserted. There is.

By setting in this way, the tip of the extension tube portion 52 (guide convex portion) of the cylindrical tube 50 guides before the front end of the lock tongue piece 86 reaches the starting point of the front slope 26a of the lock convex portion 26. It is inserted into the hole 72 (guide recess). As a result, the pump unit 2 and the filter unit 3 are centered. Then, in this state, the lock tongue piece 86 rides on the lock convex portion 26 while elastically deforming outward, and then the lock hole 86a engages with the lock convex portion 26 while elastically returning to achieve locking.

Further, the O-ring 56 is the O-ring fitting hole portion 73 in a state where the tip of the extension pipe portion 52 (guide convex portion) of the cylindrical tube 50 is inserted into the guide hole portion 72 (guide concave portion) and the alignment is performed. Will be inserted in. Therefore, the O-ring 56 is not caught between the member on the filter unit 3 side, and the damage of the O-ring 56 is avoided.

(Action)
Next, the operation will be described.
When the pump unit 2 and the filter unit 3 are coupled, the filter unit 3 is axially slid with respect to the pump unit 2 while aligning the filter unit 3 with respect to the pump unit 2 in the circumferential direction. Then, the tip of the extension pipe portion 52 of the cylindrical pipe 50 of the pump unit 2 is inserted into the guide hole portion 72 of the internal through hole 70 of the cylindrical boss portion 62 of the filter unit 3. By inserting the tip of the extension pipe portion 52 of the cylindrical pipe 50 into the guide hole portion 72, the pump unit 2 and the filter unit 3 are centered. Further, along with this operation, the lock tongue piece 86 at the front end of the cylindrical hood portion 84 of the filter unit 3 abuts on the starting point of the front slope of the lock convex portion 26 of the pump unit 2.

Then, when the sliding operation is further performed in the axial direction, the O-ring 56 mounted on the outer periphery of the base portion of the cylindrical tube 50 is inserted into the O-ring fitting hole portion 73 of the internal through hole 70 of the cylindrical boss portion 62 of the filter unit 3. At this time, the lock tongue piece 86 of the filter unit 3 is elastically deformed outward in the radial direction, overcomes the lock convex portion 26 of the pump unit 2, and the lock hole 86a of the lock tongue piece 86 is engaged with the lock convex portion 26. It fits. At the same time, the insertion tongue piece 87 on the filter unit 3 side is fitted into the insertion frame 27 on the pump unit 2 side.

When such a locked state is achieved, the O-ring 56 inserted into the O-ring fitting hole 73 of the internal through hole 70 of the cylindrical boss portion 62 is the step portion 51 for receiving the O-ring on the pump unit 2 side. It is sandwiched and confined between and the step portion 71 for receiving the O-ring on the filter unit 3 side. As a result, the internal through hole 50a of the cylindrical pipe 50 (fuel suction port on the pump unit 2 side) and the internal through hole 70 of the cylindrical boss portion 62 (fuel outlet on the filter unit 3 side) are connected via the O-ring 56. It is connected in a liquidtight manner.

Further, by inserting the tip of the cylindrical boss portion 62 of the filter unit 3 into the abutting groove 42 of the pump unit 2, the abutting surfaces 42a and 62a abut against each other, whereby the pump unit 2 and the filter unit 3 are axially oriented. Positioned to. Then, the matching plates 40 and 61 of the pump unit 2 and the filter unit 3 are combined under appropriate positioning conditions so that an excessive external force is not applied to the O-ring 56. Further, the convex walls 43, 63 and the recesses 64, 44 of the mating surface 41a of the pump unit side mating plate 40 and the mating surface 61a of the filter unit side mating plate 61 are fitted to each other, so that the two units 2 and 3 are aligned. A labyrinth is formed between the surfaces 41a and 61a.

In the assembled state in this way, the fuel pump module 1 is mounted on the vehicle in a predetermined posture, the fuel suction pipe 4 and the fuel return pipe 6 are connected to the fuel tank, and the fuel discharge pipe 5 is connected to the internal combustion engine side. .. Then, by operating the fuel pump module 1, the fuel filtered by the filter unit 3 is boosted by the pump unit 2, adjusted by the pressure regulator, and then pumped toward the internal combustion engine.

The flow of fuel and air bubbles in the filter unit 3 during this operation will be described with reference to FIGS. 9 (a) and 10 (a) and 10 (b).
10A and 10B are schematic explanatory views showing the flow of fuel and bubbles of the filter unit, FIG. 10A is a schematic plan view seen from above vertically, and FIG. 10B is a schematic front view seen from a horizontal direction.

In this filter unit 3, as shown in FIG. 10B, the communication port 4h through which fuel flows from the internal passage of the fuel suction pipe 4 into the internal space of the filter unit case 80 is from the internal through hole 70 of the filter cartridge 60. Also opens at a high position. Further, as is clear from FIGS. 5 and 10B, the opening area of the communication port 4h between the fuel intake pipe 4 and the filter unit case 80 becomes large. Therefore, the inflow of the fuel N from the fuel suction pipe 4 to the filter unit case 80 and the discharge of the bubble V from the filter unit case 80 to the fuel suction pipe 4 can be smoothly performed while reducing mutual interference. become able to.

Especially at high temperatures, a large amount of bubbles may be generated from the fuel, and even in such a case, the flow of bubbles from the filter unit case 80 to the fuel suction pipe 4 can be smoothed. Therefore, the gas-liquid exchangeability can be improved, and as a result, a sufficient amount of fuel can be stored in the filter unit case 80, and the fuel supply to the pump unit 2 becomes insufficient. There will be no such thing.

Further, by satisfying the above-mentioned conditions (1), (2), and (3), fuel and air bubbles can be obtained while making the communication port 4h connecting the internal passage of the fuel intake pipe 4 and the internal space of the filter unit case 80 as large as possible. It is possible to reduce the retention of fuel and promote smooth gas-liquid exchange.

As shown in FIG. 10A, the base end side of the fuel suction pipe 4 is joined at a corner position from the rear end of the outer surface portion of the cylindrical peripheral wall 81 of the filter unit case 80 to the end wall 83. .. Therefore, the discharge of the bubbles V generated in the filter unit case 80 and the inflow of the fuel N from the fuel suction pipe 4 can be performed more smoothly, and the gas-liquid exchangeability can be further improved.

On the other hand, when the coupling between the pump unit 2 and the filter unit 3 is released at the time of maintenance, the pump unit 2 and the filter unit 3 are separated in the axial direction while disengaging the lock convex portion 26 and the lock tongue piece 86. By doing so, the filter unit 3 can be easily removed from the pump unit 2.

(effect)
In the above configuration, in the filter unit 3, a part of the fuel intake pipe 4 projects outward from the internal space of the filter unit case 80 when viewed from the extending direction of the fuel intake pipe 4. Therefore, the communication port 4h that communicates the internal passage of the fuel intake pipe 4 with the internal space of the filter unit case 80 can be made as large as possible. Therefore, at the communication port 4h, it is possible to sufficiently secure a passage through which air bubbles actively pass and a passage through which fuel actively passes. As a result, the inflow of fuel from the fuel suction pipe 4 to the filter unit case 80 and the discharge of air bubbles from the filter unit case 80 to the fuel suction pipe 4 can be smoothly performed while reducing mutual interference. Even when a large amount of air bubbles are generated from the fuel especially at a high temperature, the flow of air bubbles from the filter unit case 80 to the fuel suction pipe 4 can be smoothed. That is, the gas-liquid exchangeability can be improved. Therefore, a sufficient amount of fuel can be stored in the filter unit case 80, and it is possible to prevent the fuel supply to the pump unit 2 (pump main body 10) from becoming insufficient.

In particular, when the fuel suction pipe 4 is viewed from the extending direction of the fuel suction pipe 4, more than half of the opening area of the inner peripheral surface 4a of the cylinder overlaps with the internal space of the filter unit case. Therefore, the communication port 4h can be formed as large as possible.
Further, in the filter unit case 80, the communication port 4h can be maximized by arranging the fuel suction pipe 4 so as to satisfy the above-mentioned conditions (1), (2), and (3).

Further, the fuel suction pipe 4 is joined to a corner portion from the outer surface portion of the cylindrical peripheral wall 81 of the filter unit case 80 to the end wall 83 with the tip opening 4b facing upward. Therefore, of the internal passages of the fuel intake pipe 4, half of the filter unit case 80 side can be used as a passage through which air bubbles actively pass. Further, of the internal passage of the fuel suction pipe 4, the half on the side opposite to the filter unit case 80 side can be a passage through which fuel positively passes. Therefore, the bubbles generated in the filter unit case 80 and the inflow of fuel from the fuel suction pipe 4 can be smoothly performed, and the gas-liquid exchangeability can be further improved.

Further, when the filter cartridge 60 is mounted inside the filter unit case 80, the rear surface plate 67 of the filter cartridge 60 and the end wall 83 of the filter unit case 80 face each other in the axial direction via a minute gap S. When the fuel suction pipe 4 is viewed from the extending direction of the fuel suction pipe 4, the inner peripheral surface of the cylinder 4a and the rear surface plate 67 of the filter cartridge 60 overlap each other. Further, the rear surface plate 67 of the filter cartridge 60 and the end wall 83 of the filter unit case 80 face each other in the axial direction via a minute gap S. Therefore, it is possible to make it difficult for air bubbles to be discharged from the minute gap S. As a result, fuel can be easily introduced between the rear surface plate 67 and the end wall 83 of the filter unit case 80. Therefore, the air bubbles generated in the filter unit case 80 can be smoothly discharged and the fuel can be smoothly flowed in from the fuel intake pipe, and the gas-liquid exchangeability can be further improved.

Further, since the fuel pump module 1 has the pump unit 2 and the filter unit 3 detachably connected to each other, the filter cartridge 60 in the filter unit 3 can be easily replaced by removing the filter unit 3 from the pump unit 2. Is possible and maintenance is easy.

Further, by simply sliding the pump unit 2 and the filter unit 3 in the axial direction and locking them, the fuel suction port of the pump unit 2 (internal through hole 50a of the cylindrical pipe 50) and the fuel outlet of the filter unit 3 (cylindrical boss portion) The internal through hole 70) of 62 can be connected in a liquid-tight manner via an O-ring 56. Therefore, the fuel pump module 1 can be easily assembled.
Further, a snap-fit type locking means that can engage the lock tongue piece 86 and the lock convex portion 26 by simply sliding the pump unit 2 and the filter unit 3 in the axial direction is adopted. Therefore, both units 2 and 3 can be easily combined.

Further, of the four pairs of lock tongue pieces 86 of the filter unit case 80, at least one side of the lock tongue piece 86A faces the direction closest to the direction in which the fuel suction pipe 4 protrudes from the filter unit case 80. Is formed so that both inner side surfaces 86a1 along the axial direction are along the extending direction of the fuel suction pipe 4. As a result, when the filter unit case 80 is molded with resin, for example, it is possible to set the sliding direction (the die removing direction) of a part of the mold forming the fuel suction pipe 4 and the lock tongue piece 86A to be the same. become. Therefore, the mold can be simplified by this amount.

Further, convex walls 43, 63 and recesses 44, 64 are provided between the mating plates 40, 61 of the pump unit 2 and the filter unit 3 to form a labyrinth only by mating the mating surfaces 41a, 61a with each other. Therefore, the path between the pump unit 2 and the mating plates 40 and 61 of the filter unit 3 from the outside to the vicinity of the O-ring 56 can be complicated or lengthened. As a result, it is possible to prevent foreign matter such as dust from entering through the gap between the mating plates 40 and 61 of the pump unit 2 and the filter unit 3 as much as possible by the labyrinth effect without incurring a simple configuration and cost. Therefore, it is possible to improve the reliability of ensuring the sealability of the fuel passage by the O-ring 56.

Further, the cylindrical hood portion 84 extending from the filter unit 3 side toward the pump unit 2 side surrounds the periphery of the mating plates 40 and 61 of the pump unit 2 and the filter unit 3. Therefore, it is possible to reduce dust from entering between the mating plates 40 and 61 from the outside as much as possible.

Further, even if foreign matter such as dust enters the gap between the mating plates 40 and 61 of the pump unit 2 and the filter unit 3, the discharge provided on the mating surfaces 41a and 61a due to the vibration or shaking of the vehicle. Foreign matter such as dust can be gradually dropped downward together with the leaked fuel through the grooves 45 and 65 and naturally discharged to the outside. That is, when mounted on a vehicle such as a motorcycle, foreign matter such as dust may enter the inside from the entire circumference between the mating plates 40 and 61 depending on the driving conditions and the driving environment. However, foreign matter such as dust can be naturally leaked and discharged downward together with the fuel due to the vibration or shaking of the vehicle. Therefore, it is possible to improve the reliability of the sealing performance especially when it is mounted on a vehicle such as a motorcycle. In this case, if the discharge grooves 45 and 65 are provided directly downward, the invading dust can be more reliably discharged to the outside.

Further, when the two units 2 and 3 are connected, the tip of the extension pipe portion 52 of the cylindrical pipe 50 on the pump unit 2 side is first inserted into the guide hole portion 72 of the cylindrical boss portion 62 on the filter unit 3 side. Later, the dimensions are set so that the O-ring 56 fits into the O-ring fitting hole 73 of the cylindrical boss portion 62. Therefore, the O-ring 56 is inserted into the mating unit (filter unit 3) after the pump unit 2 and the filter unit 3 are aligned. As a result, even when a flexible snap fit (combination of the lock convex portion 26 and the lock tongue piece 86) is used as the locking means, the O-ring 56 is engaged with the mating unit (filter unit 3). Such troubles can be avoided. Therefore, damage due to biting of the O-ring 56 can be effectively prevented.

Further, a cylindrical pipe 50 having an internal through hole 50a as a fuel suction port is used as a guide convex portion for alignment, and a cylindrical boss portion 62 having an internal through hole 70 as a fuel outlet is used as a guide concave portion. Therefore, the guide means and the fuel passage (fuel intake port and fuel outlet) can be shared, and the structure can be simplified.

Further, the tip of the extension tube portion 52 of the cylindrical tube 50 is inserted into the guide hole portion 72 of the cylindrical boss portion 62 before the front end of the lock tongue piece 86 abuts on the front slope of the lock convex portion 26. Therefore, after the two units 2 and 3 are aligned with each other, the lock tongue piece 86 begins to elastically deform. Therefore, misalignment occurs between the two units 2 and 3 due to the locking operation, and therefore, a non-uniform force is not applied depending on the location of the two units 2 and 3. As a result, troubles such as the O-ring 56 getting caught in the mating unit (filter unit 3) can be prevented.

Further, in order to align the two units 2 and 3 with each other, that is, to use the tip of the cylindrical tube 50 as a guide convex portion, the extension tube portion 52 is extended to the tip of the cylindrical tube 50. As a result, the occupied volume of the cylindrical tube 50 that enters the inside of the filtered space 69 of the filter cartridge 60 increases. As a result, the substantial volume of the post-filtration space in the filter cartridge 60 can be reduced, and the effect of reducing the gas volume in the filter cartridge 60 can be obtained. Incidentally, in a state where a large amount of gas (bubbles) is contained in the filter cartridge 60 (at high temperature, etc.), the fuel suction efficiency of the pump body 10 deteriorates, which may adversely affect the startability of the internal combustion engine. Such adverse effects can be reduced.

Further, when the tip side of the cylindrical tube 50 is used as a guide convex portion and is largely entered into the filter cartridge 60, the advantage that the actual volume of the filtered space 69 in the filter cartridge 60 can be reduced as described above can be obtained. If the fuel suction port is only the opening at the tip of the cylindrical tube 50, a new problem arises that the fuel suction efficiency by the pump body 10 is deteriorated. In particular, when the cylindrical tube 50 maintains a horizontal posture, it becomes difficult for fuel to enter the inside of the cylindrical tube 50. Therefore, a slit 52a is provided on the peripheral wall of the extension pipe portion 52 at the tip of the cylindrical pipe 50 as a communication portion such as a slit. By doing so, the fuel suction efficiency is improved and the gas-liquid exchange performance is improved. Further, the gas-liquid exchange performance is also improved by increasing the inner diameter of the cylindrical tube 50. Further, by providing a communication portion such as a slit on the peripheral wall on the tip side of the cylindrical tube 50, the gas-liquid exchange performance can be improved regardless of the diameter and length of the cylindrical tube 50.

The number, shape, and dimensions of the slits 52a are not limited. Further, a through hole may be provided as a communication portion instead of the slit 52a. In this case as well, the number, shape, and dimensions of the through holes do not matter. If the slits and through holes are formed large, the rigidity of the tip side (extension pipe portion 52) of the cylindrical tube 50 may be insufficient, and the function as the guide convex portion, which is the original purpose, may not be achieved. It is desirable to set the diameter of the cylindrical tube 50 and the shape and dimensions of the communication portions (slits and through holes) so that the cylinder tube 50 can be maintained. When molding the cylindrical tube 50 with resin, a slit is preferable because of ease of molding.

Further, an insertion frame 27 and an insertion tongue piece 87 are provided next to the lock convex portion 26 and the lock tongue piece 86 so that they fit each other when the two units 2 and 3 are connected. Therefore, in the coupled state of the units 2 and 3, the rigidity around the mating portion of the filter unit case 80 can be increased. As a result, the easiness of elastic deformation of the lock tongue piece 86 in the radial direction can be reduced. In addition, displacement in the circumferential direction can be prevented. Therefore, the engagement between the lock convex portion 26 and the lock hole 86a (snap fit) of the lock tongue piece 86 becomes difficult to disengage.

Further, when locking, the lock convex portion 26 and the lock tongue piece 86 are engaged with each other by simply sliding the two unit cases 20 and 80 together while aligning them in the axial direction. can do. In addition to this, the insertion tongue piece 87 can also be fitted into the insertion frame 27. Therefore, while ensuring the ease of attachment / detachment, it is possible to exert strength particularly against vibration and impact in the twisting direction. Since the insertion frame 27 and the insertion tongue piece 87 may be arranged adjacent to the lock convex portion 26 and the lock tongue piece 86, the proof stress against vibration and impact can be increased without increasing the outer diameter.

Further, the cylindrical hood portion 84 on the filter unit 3 side fits into the end portion of the pump unit 2. As a result, it is possible to increase the proof stress of the joint portion of the two units 2 and 3 against vibration and impact in the twisting direction.

The present invention is not limited to the above-described embodiment, and includes various modifications of the above-described embodiment without departing from the spirit of the present invention.

For example, in the above embodiment, the case where the cross-sectional shapes of the convex walls 43 and 63 provided on the mating surfaces 41a and 61a of the mating plates 40 and 61 are rectangular has been described, but trapezoidal, triangular, semicircular, corrugated and the like are arbitrary. It may be shaped. At this time, it is preferable to change the shape of the concave portion into which the convex wall is fitted according to the cross-sectional shape of the convex wall. Further, the cross-sectional shape of the convex wall of one mating surface and the cross-sectional shape of the other mating surface may be different, or the cross-sectional shapes of a plurality of convex walls on the same mating surface may be different.

Further, in the above embodiment, the case where the convex walls 43 and 63 are provided on both the mating surfaces 41a and 61a has been described, but one mating surface may be a flat surface and the convex wall may be provided only on the other mating surface.

Further, the number of convex walls 43 and 63 is preferably large, but may be small or one. However, a labyrinth effect can be obtained by providing two or more convex walls on one mating surface and inserting the convex wall of the other mating surface into the recess between the convex walls.

Further, in the above embodiment, the case where the convex walls 43 and 63 are provided in a continuous annular shape has been described, but the convex walls 43 and 63 may be provided in a dotted manner. In any case, if a labyrinth or at least one bottleneck is formed in the radial path, a certain degree of dust intrusion prevention effect can be obtained.

Further, although the discharge grooves 45 and 65 are formed by providing the notches 43a and 63a in a part of the annular convex walls 43 and 63 in the circumferential direction, the discharge grooves may not be provided. Further, even when the discharge grooves are provided, the number of the discharge grooves is not limited. However, if there is a large amount, the possibility of dust entering will increase.

Further, since the mating plates 40 and 61 are complicated in shape, it is desirable to mold them with a resin (for example, POM: polyacetal), but the mating plates 40 and 61 may be made of any material such as metal, not limited to the resin.

Further, in the case of manufacturing with resin, for example, if the penetration direction of some of the lock holes 86a of the plurality of lock tongue pieces 86 is configured to match the axial direction of the fuel suction pipe 4, the core of the mold can be formed. The matching of the drawing directions makes it possible to simplify the mold configuration.

Further, in the above embodiment, when the cylindrical pipe 50 having the internal through hole 50a as the fuel suction port and the cylindrical boss portion 62 having the internal through hole 70 as the fuel outlet are used as the guide convex portion and the guide concave portion for centering. Said. However, the present invention is not limited to this, and the guide convex portion and the guide concave portion may be provided at positions different from those of the cylindrical tube 50 and the cylindrical boss portion 62. In short, it suffices if the pump unit 2 and the filter unit 3 can be aligned at the time of coupling. Therefore, if the configuration is complicated, the mating plates 40 and 61 may be provided at any position so that they can be fitted to each other.

Further, in the above embodiment, the case where the cylindrical tube 50 having the function of the guide convex portion is provided on the pump unit 2 side and the cylindrical boss portion 62 having the function of the guide concave portion is provided on the filter unit 3 side has been described. However, the present invention is not limited to this, and on the contrary, a cylindrical tube having a function of a guide convex portion is provided on the filter unit 3 side, and a cylindrical boss portion having a function of a guide concave portion is provided on the pump unit 2 side. May be good.

Further, in the above embodiment, the case where the lock convex portion 26 is provided on the pump unit 2 side and the lock tongue piece 86 which is elastically deformed and engages with the lock convex portion 26 is provided on the filter unit 3 side. However, the present invention is not limited to this, and conversely, a lock convex portion may be provided on the filter unit 3 side, and a lock tongue piece that elastically deforms and engages with the lock convex portion may be provided on the pump unit 2 side. Good. In this case, it is preferable to provide a cylindrical hood portion that fits on the outer circumference of the filter unit 3 on the pump unit 2 side. At this time, the insertion frame 27 and the insertion tongue piece 87 are also provided on opposite sides. That is, the insertion tongue piece is extended to the cylindrical hood portion provided on the pump unit 2 side, and the insertion frame is provided on the outer periphery on the filter unit 3 side.

Further, the number of locking means (lock convex portion 26 and lock tongue piece 86) and the number of deformation controlling means (insertion frame 27 and insertion tongue piece 87) are not limited.
Further, in the above embodiment, the case where the case to be connected (pump unit case 20 and filter unit case 80) is a cylindrical case has been described, but other tubular cases may be used.

Further, the inner peripheral surface 81a of the cylindrical peripheral wall 81 of the filter unit case 80 and the cylindrical inner peripheral surface 4a of the fuel suction pipe 4 do not necessarily have to be a perfect circular cylinder, and either one or both of them may be elliptical or different. It may be an inner peripheral surface having a cross-sectional shape of.

1 ... Fuel pump module 2 ... Pump unit 3 ... Filter unit 4 ... Fuel suction pipe 4a ... Cylindrical inner peripheral surface (second cylindrical inner peripheral surface)
4b ... Tip opening 4c ... Inner bottom surface 4h on the base end side ... Communication port 4x ... Central axis 5 ... Fuel discharge pipe 10 ... Pump body 11 ... Suction port 12 ... Discharge port 13 ... O-ring 20 ... Pump unit case 21 ... Cylindrical peripheral wall 22 ... Pump body accommodation space 23 ... End wall 26 ... Lock convex part 27 ... Insertion frame 40 ... Pump unit side mating plate 41 ... Plate body 41a ... Laminating surface 42 ... Lump groove 42a ... Lump surface 43 ... Convex wall 43a ... Notch 44 ... Recess 45 ... Discharge groove 48 ... Support rod 48a ... Slit 50 ... Cylindrical pipe 50a ... Fuel suction port 51 ... Step 52 ... Extension of cylindrical pipe (guide convex part)
56 ... O-ring 60 ... Filter cartridge 61 ... Alignment plate 61a ... Alignment surface 62 ... Cylindrical boss portion 62a ... Butt surface 63 ... Convex wall 63a ... Notch 64 ... Recess 65 ... Discharge groove 67 ... Rear plate 68 ... Filter element 69 ... Space after filtration 70 ... Through hole (fuel outlet)
80 ... Filter unit case 81 ... Cylindrical peripheral wall (cylindrical peripheral wall)
81a ... Cylinder inner peripheral surface (first cylindrical inner peripheral surface)
82 ... Filter cartridge accommodation space 83 ... End wall 84 ... Hood part 85 ... Alignment plate annular support part 86 ... Lock tongue piece 86a ... Lock hole 87 ... Insertion tongue piece X ... Central axis of filter unit M ... Interpenetrating line

Claims (5)

A bottomed tubular filter unit case having a tubular peripheral wall and an end wall that closes one end opening of the tubular peripheral wall,
A fuel intake pipe having a tubular shape extending in a direction intersecting the axial direction of the filter unit case and having a base end side joined to the outer surface portion of the tubular peripheral wall of the filter unit case.
A filter cartridge housed concentrically with the inner peripheral surface of the tubular peripheral wall inside the filter unit case,
With
The internal passage of the fuel suction pipe is provided through a communication port surrounded by an interpenetrating line at which the inner peripheral surface of the fuel suction pipe and the inner peripheral surface of the tubular peripheral wall of the filter unit case intersect. It is connected to the internal space of the case and
When viewed from the extending direction of the fuel intake pipe, a part of the internal passage projects outward from the internal space of the filter unit case .
The inner peripheral surface of the tubular peripheral wall of the filter unit case is the inner peripheral surface of the first cylinder having a radius R, and the inner peripheral surface of the fuel suction pipe is the inner peripheral surface of the second cylinder having a radius r. Has been
Let D be the distance between the first central axis of the inner peripheral surface of the first cylinder and the second central axis of the inner peripheral surface of the second cylinder of the fuel suction pipe, and from the height of the central axis of the filter unit case. When the value obtained by subtracting the height of the end portion on the base end side of the internal passage of the fuel suction pipe is Z1, the radius R, the radius r, the distance D, and the value Z1 are
2r <R
Rr <D ≤ R
0 <Z1 <R
A fuel filter characterized by being set to meet . The first aspect of claim 1, wherein when the fuel intake pipe is viewed from the extending direction of the fuel intake pipe, more than half of the opening area of the internal passage overlaps with the internal space of the filter unit case. Fuel filter. The fuel according to claim 1 or 2 , wherein the base end side of the fuel suction pipe is joined to a corner portion from the outer surface portion of the tubular peripheral wall of the filter unit case to the end wall portion. filter. The filter cartridge is
A tubular filter element that filters fuel by allowing fuel to permeate from the outer peripheral side to the inner peripheral side,
A rear face plate arranged near the end wall of the filter unit case while closing one end opening of the filter element, and
It is composed of a front plate having a fuel outlet that closes the other end opening of the filter element and guides fuel that has permeated through the space on the inner peripheral side of the filter element to the outside at the center.
The method according to any one of claims 1 to 3 , wherein the internal passage and the rear surface plate overlap when the fuel intake pipe is viewed from the extending direction of the fuel intake pipe. Fuel filter. The fuel filter according to any one of claims 1 to 4 .
It is equipped with a pump unit that sucks liquid fuel from the fuel tank and discharges it to the outside.
The fuel filter is a fuel pump module characterized in that the liquid fuel introduced from the fuel tank is filtered and led out to the pump unit.

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