CN103261654A - Fuel supply device - Google Patents

Abstract

A fuel supply device (1), comprising a flange unit (4) (housing) mounted on a bottom wall (2b) (bottom surface) of a fuel tank (2), a fuel pump (3) comprising a motor part (30) and a metal casing (20) covering the periphery of the pump part (40). The pump part (40) has a pump casing (45) made of resin, and a pump The housing (45) abuts against the protruding part (21), and the fuel pump (3) is supported by the flange unit (4) via the protruding part (21).

Description

fuel supply device

technical field

The invention relates to a fuel supply device. this application claims priority based on Japanese Patent Application No. 2010-288664 for which it applied in Japan on December 24, 2010, and uses the content of this application here.

Background technique

Generally, as a vehicle fuel supply device for a motorcycle or a four-wheel vehicle, a so-called built-in type (Japanese: Intank type) fuel supply device in which a fuel pump is arranged in a fuel tank is used. As such a fuel supply device, there is known a structure in which a pump assembly (corresponding to the “fuel pump” of the present application) is housed in a flange unit and an upper cup is mounted thereon (see, for example, Patent Document 1).

In the fuel pump of the fuel supply device of Patent Document 1, the motor, the pump unit, the pressure regulator, and the check valve are integrally housed in a steel outer case (Japanese: シェルケース) (equivalent to the "outer case" in this application). )Inside. An inlet cover (corresponding to the “pump case” in the present application) is caulked and fixed to one end side of the cylindrical housing case.

In addition, the bottom of the flange unit forms a tank portion for storing fuel. The positioning protrusion is provided in an upright state from the tank portion toward the fuel pump. In addition, the fuel pump can be supported by the flange unit and the upper cup by abutting the positioning protrusion on one end side of the pump housing and attaching the upper cup from the other end side of the housing housing (refer to Patent Document 1 figure 1).

Here, the impeller connected to the rotating shaft of the electric motor is housed inside the pump housing. However, when the impeller is in contact with the inner surface of the pump housing, sliding resistance increases to reduce the efficiency of the fuel pump. Therefore, it is necessary to maintain a constant gap between the inner surface of the pump housing and the impeller so as to prevent the impeller from coming into contact with the inner surface of the pump housing.

However, in the structure in which the positioning protrusion abuts on the pump housing as described above, when the fuel pump discharges fuel, the pump housing receives a reaction force of the discharge pressure, thereby deforming the pump portion. In addition, when the fuel pump is subjected to a large vibration and impact load, the vibration and impact load will be directly transmitted from the positioning protrusion to the pump housing. As a result, the pump casing is deformed, and the gap between the inner surface of the pump casing and the impeller cannot be maintained constant. Therefore, the pump casing of Patent Document 1 is formed of metal by aluminum die-casting or the like, so that it does not deform even when it receives the reaction force of the discharge pressure.

prior art literature

patent documents

Patent Document 1: Japanese Patent Laid-Open No. 2009-62813

Contents of the invention

The technical problem to be solved by the invention

However, for the purpose of cost reduction, it is conceivable to change the material of the pump housing from metal such as aluminum to resin. However, in general, when the material of the pump housing is changed from aluminum to resin, the strength of the pump housing is reduced. Therefore, in the structure in which the positioning protrusion abuts on the pump housing as described above, the pump housing formed of resin is deformed. When the pump housing is deformed, the gap between the inner surface of the pump housing and the impeller disappears, increasing the sliding resistance due to the contact between the impeller and the inner surface of the pump housing, thereby reducing the efficiency of the fuel pump .

The present invention provides a low-cost fuel supply device capable of suppressing deformation of a pump casing formed of resin and contact between an impeller and the inner surface of the pump casing, and preventing damage due to an increase in sliding resistance. The resulting reduced efficiency of the fuel pump.

Technical solutions adopted to solve technical problems

In order to solve the above-mentioned technical problems, the fuel supply device of the first technical solution of the present invention includes: a fuel pump, which is arranged in the fuel tank, and pumps the fuel in the fuel tank to deliver it to the internal combustion engine under pressure; and a casing, the The casing supports the fuel tank and is attached to a wall surface of the fuel tank. In addition, the fuel pump includes: a motor unit; a pump unit provided under the motor unit; and a metal housing case that covers the motor unit and the pump unit. In addition, the pump unit has a pump case formed of resin. In addition, a protruding portion that comes into contact with the pump case is formed inside the housing case. In addition, the fuel pump is supported by the housing via the protruding portion.

According to the fuel supply device according to the first aspect of the present invention, when the fuel pump is placed in the housing, the fuel pump is supported by the housing via the protruding portion of the casing housing. Therefore, even if an external force such as a reaction force of the discharge pressure is generated, the external force is not directly transmitted to the resin pump case. Thus, deformation of the pump housing formed of resin and contact between the impeller and the inner surface of the pump housing can be suppressed, and reduction in efficiency of the fuel pump due to an increase in sliding resistance can be prevented.

In addition, since the pump case is formed of resin, the pump case can be formed at low cost compared with the case where the pump case is formed of, for example, metal by aluminum die molding or the like. Therefore, a low-cost fuel supply device can be provided.

In addition, in the fuel supply device according to the second aspect of the present invention, a base portion that supports the pump housing through the protruding portion is provided in the housing.

According to the fuel supply device according to the second aspect of the present invention, when the fuel pump is placed in the housing, the base portion of the housing comes into contact with the protruding portion of the housing case. Therefore, the base portion does not directly contact the pump housing, but the fuel pump can be supported via the protruding portion. As a result, even if an external force such as a reaction force of the discharge pressure is generated, the external force is not directly transmitted from the base portion to the pump case. Thus, deformation of the pump housing formed of resin and contact between the impeller and the inner surface of the pump housing can be reliably suppressed, and efficiency reduction of the fuel pump due to an increase in sliding resistance can be effectively prevented.

In addition, the fuel supply device according to the third aspect of the present invention is formed to support the pump housing via the base of the protruding portion.

Since the base of the protruding portion is supported by the lower end portion of the case, it has a higher strength than that of the front end of the protruding portion. According to the fuel supply device according to the third aspect of the present invention, the base portion supports the pump case through the root portion of the strong protruding portion. Therefore, deformation of the protruding portion can be suppressed. Thus, deformation of the pump housing formed of resin and contact between the impeller and the inner surface of the pump housing can be suppressed, and reduction in efficiency of the fuel pump due to an increase in sliding resistance can be prevented.

In addition, in the fuel supply device according to the fourth embodiment of the present invention, a sealing member is provided between the pump housing and the protruding portion.

According to the fuel supply device according to the fourth embodiment of the present invention, even if an external force such as a reaction force of the discharge pressure is generated, the external force cannot be absorbed by the sealing member provided between the pump housing and the protrusion. Therefore, the external force transmitted to the pump housing can be relaxed. Therefore, deformation of the pump housing formed of resin and contact between the impeller and the inner surface of the pump housing can be suppressed, and reduction in efficiency of the fuel pump due to an increase in sliding resistance can be prevented. In addition, stable fuel pump performance can be maintained for a long period of time.

In addition, in the fuel supply device according to the fifth aspect of the present invention, the protruding portion constitutes an inner flange portion formed at a lower end portion of the housing case.

According to the fuel supply device according to the fifth aspect of the present invention, since the protruding portion can be firmly formed, deformation of the protruding portion can be suppressed. Thus, deformation of the pump housing formed of resin and contact between the impeller and the inner surface of the pump housing can be reliably suppressed, and a reduction in efficiency of the fuel pump due to an increase in sliding resistance can be prevented. In addition, the motor unit and the pump unit can be reliably integrated. In addition, since the sealing member is reliably in close contact with the pump housing and the protruding portion, the sealing performance can be improved.

In addition, a fuel supply device according to a sixth aspect of the present invention is attached to the bottom wall of the fuel tank, and the fuel pump is mounted on the base portion formed in the casing.

According to the fuel supply device according to the sixth aspect of the present invention, the above structure can be applied to a fuel supply device attached to the bottom wall of the fuel tank. The above structure is ideally used in a so-called undermount type fuel supply device in which the flange unit is provided on the lower side of the fuel pump. Therefore, in the fuel supply device fixed to the lower side of the fuel tank, deformation of the pump housing formed of resin and contact between the impeller and the inner surface of the pump housing can be reliably suppressed, and an increase in sliding resistance due to This results in a reduction in the efficiency of the fuel pump.

Invention effect

According to the fuel supply device according to the embodiment of the present invention, when the fuel pump is placed in the case, the fuel pump is supported by the case via the protruding portion of the housing case. Therefore, even if an external force such as a reaction force of the discharge pressure is generated, the external force is not directly transmitted to the resin pump case. Thus, deformation of the pump housing formed of resin and contact between the impeller and the inner surface of the pump housing can be suppressed, and reduction in efficiency of the fuel pump due to an increase in sliding resistance can be prevented.

In addition, since the pump case is formed of resin, the pump case can be formed at low cost compared with the case where the pump case is formed of, for example, metal by aluminum die molding or the like. Therefore, a low-cost fuel supply device can be provided.

Description of drawings

Fig. 1 is a perspective view showing a fuel supply device according to a first embodiment of the present invention.

Fig. 2 is a cross-sectional view along line AA of Fig. 1 .

FIG. 3 is an enlarged view of area B of FIG. 2 .

Fig. 4 is a perspective view of a flange unit according to a first embodiment of the present invention.

Fig. 5 is a perspective view showing a fuel supply device according to a second embodiment of the present invention.

Fig. 6 is a sectional view taken along line CC of Fig. 5 .

FIG. 7 is an enlarged view of area D of FIG. 6 .

Fig. 8 is a perspective view showing a lower cup according to a second embodiment of the present invention.

Detailed ways

(First Embodiment, Downward Type Fuel Supply Device)

Hereinafter, a fuel supply device according to a first embodiment of the present invention will be described with reference to the drawings. In addition, the undermount type fuel supply device includes an overmount type fuel supply device in which a fuel pump is attached to an upper portion of a fuel tank and an undermount type fuel supply device in which a fuel pump is attached to a bottom of a fuel tank. In the first embodiment of the present invention, the bottom type is taken as an example for description. In addition, the relative positions in the axial direction of the fuel pump are simply expressed as upper side and lower side.

The fuel supply device 1 is inserted through an opening 2 a formed in a bottom wall 2 b of the fuel tank 2 (see FIG. 2 ), and is attached to the bottom wall 2 b of the fuel tank 2 . The fuel supply device 1 includes: a fuel pump 3 arranged in the fuel tank 2; an upper cup 25 sleeved on the fuel pump 3; and a flange unit installed on the bottom wall 2b of the fuel tank 2 and supporting the fuel pump 3 4 ("Shell").

(fuel pump)

The fuel pump 3 is formed in a substantially cylindrical shape, and has a motor unit 30 arranged above the fuel pump 3 and a pump unit 40 arranged below the fuel pump 3 .

For the motor unit 30 , for example, a DC motor 30 a with brushes (not shown) can be used.

An output shaft 30 b pivotally supported by the upper side of the motor unit 30 and the lower side of the pump unit 40 so as to be rotatable is arranged at the center of the motor unit 30 . In addition, the pump part 40 side of the output shaft 30b has a D-shaped cut surface (not shown) for position regulation which will be described later.

In addition, on the upper side of the motor unit 30 , a pair of motor terminals 32 electrically connected to the brushes are provided on the upper side of the fuel pump 3 so as to stand upright along the central axis O. As shown in FIG. A pair of motor terminals 32 is connected to the wire harness 6 . The external power supply is electrically connected to the motor unit 60 by the wire harness 6, and electric power for driving the DC motor 30a is supplied from the external power supply.

In addition, the motor terminal 32 and the periphery of the brush on the upper side of the motor unit 30 have a slightly smaller diameter than the other portions of the motor unit 30, thereby forming a stepped portion 30c. The upper end of the housing case 20 to be described later is caulked to the stepped portion 30c.

In addition, a discharge port 31 for discharging fuel and a check valve 74 communicating with the discharge port 31 are provided on the upper side of the motor unit 30 . The discharge port 31 and the check valve 74 are connected to a fuel flow path unit 52 described later to communicate with the fuel flow path unit.

The check valve 74 is a member for preventing the fuel discharged from the discharge port 31 from flowing backward from the fuel channel unit 52 into the fuel pump 3 .

(pump department)

A non-displacement type pump having an impeller 47 is used for the pump unit 40 . The pump unit 40 is composed of an impeller 47 and a pump casing 45 covering the entire impeller 47 .

The impeller 47 is a substantially disk-shaped member made of resin. An insertion hole 47 c is formed substantially at the center of the impeller 47 . The output shaft 30b of the DC motor 30a is inserted through the insertion hole 47c. For example, a D-shaped cut surface is formed in the insertion hole 47c of the impeller 47 and the impeller 47 side of the output shaft 30b. In addition, the output shaft 30b is inserted into the insertion hole 47c of the impeller 47 while making the insertion hole 47c coincide with the D-shaped cut surface of the output shaft 30b. When the impeller 47 is driven by the DC motor 30a of the motor unit 30, the relative rotation between the output shaft 30b of the DC motor 30a and the impeller 47 is restricted by the insertion hole 47c and the D-shaped cut surface of the output shaft 30b.

A plurality of blades (not shown) are formed on the outer peripheral sides of the upper surface and the lower surface of the impeller 47 . The lower surface and the upper surface of the impeller 47 pass through between the plurality of impeller parts. In addition, a fuel passage hole (not shown) penetrating the lower surface and the upper surface of the impeller 47 is formed between the insertion hole 47 c in the radial direction of the impeller 47 and the vane portion. When the DC motor 30 a is driven to rotate the impeller 47 , fuel flows through the fuel passage holes and is pressure-fed from the lower side of the impeller toward the upper side.

(pump housing)

The pump casing 45 covering the entire impeller 47 is composed of a lower casing 42 , an upper casing 43 , and a middle casing 44 . Specifically, the pump casing 45 is formed to cover the entirety of the impeller 47 by sandwiching the middle casing 44 in which the impeller 47 is disposed between the lower casing 42 and the upper casing 43 . Further, the lower case 42 , the upper case 43 , and the middle case 44 are arranged side by side in the order of pressing down the case 42 , the middle case 44 , and the upper case 43 from the lower side toward the upper side along the central axis.

Each of the lower case 42 , the upper case 43 , and the middle case 44 is made of oil-resistant resin and formed by, for example, injection molding.

The lower case 42 is a substantially disk-shaped member having substantially the same outer diameter as the motor unit 30 . A shaft support portion 42c for supporting the output shaft 30b of the DC motor 30a is formed substantially at the center of the lower case 42 . The shaft support portion 42c is a hole having a bottom, and a thrust plate (not shown) is arranged on the bottom surface. The thrust plate not only bears the axial load of the output shaft 30b, but also reduces the sliding resistance of the output shaft 30b.

On the outer diameter side of the lower surface 42b of the lower case 42, a fuel suction port 41 protruding downward is formed. The fuel intake port 41 is formed in a substantially cylindrical shape. The inner side of the fuel inlet 41 constitutes a fuel passage, and the outer side of the fuel inlet 41 is fitted into a flange unit 4 described later. Therefore, the fuel intake port 41 communicates with a filter discharge pipe 51 formed in the flange unit 4 and a filter unit (not shown) provided separately from the fuel supply device 1 .

In addition, a stepped portion 48 is formed at an edge portion of the lower surface 42 b of the lower case 42 . The stepped portion 48 is formed by reducing the diameter of the lower surface 42 b side of the lower case 42 . A corner ring 46 as a sealing member is attached to the stepped portion 48 so as to be in contact with the bottom portion 48 a of the stepped portion 48 . The corner ring 46 will be described later.

On the upper surface 42 a of the lower case 42 , a substantially C-shaped groove portion (not shown) is formed when viewed from the axial direction. A fuel passage hole (not shown) penetrating through the lower surface 42 b and the upper surface 42 a of the lower case 42 is formed on one end side of the groove portion. The fuel passage hole communicates with the fuel intake port 41 and allows the fuel sucked in from the fuel intake port 41 to flow therethrough.

Like the upper case 42 , the lower case 43 is a substantially disk-shaped member having substantially the same outer diameter as the motor unit 30 . An insertion hole 43 c is formed substantially in the center of the upper case 43 . The output shaft 30b of the DC motor 30a is inserted through the insertion hole 43c. In addition, a fuel passage hole (not shown) penetrating through the lower surface 43 b and the upper surface 43 a of the upper case 43 is formed on the outer peripheral side of the insertion hole 43 c. The fuel passage hole communicates with the motor unit 30 , and allows fuel pressure-fed from the impeller 47 to flow therethrough.

The middle case 44 is a substantially annular member having substantially the same outer diameter as the motor unit 30 .

Inside the middle case 44 , the impeller 47 is arranged so that the center axis of the middle case 44 coincides with the center axis of the impeller 47 . The inner diameter of the middle casing 44 is slightly larger than the outer diameter of the impeller 47 . In addition, a gap C1 is formed between the inner surface 44 a of the middle housing 44 (that is, the inner surface 44 a of the pump housing) and the outer peripheral surface of the impeller 47 (see FIG. 3 ). Here, the efficiency of the fuel pump 3 depends on the clearance between the pump housing 45 and the impeller 47 . Therefore, the clearance C1 is set to a predetermined value according to the required efficiency of the fuel pump 3 .

The middle case 44 is disposed between the upper case 43 and the lower case 42 . Here, the axial thickness of the middle case 44 is substantially the same as or slightly larger than the thickness of the impeller 47 described above. That is, the middle housing 44 functions as a spacer for preventing the upper surface 47a of the impeller 47 from contacting the lower surface 43b of the upper housing 43 and preventing the lower surface 47b of the impeller 47 from contacting the upper surface 42a of the lower housing 42. . In addition, a gap C2 is formed between the upper surface 47 a of the impeller 47 and the lower surface 43 b of the upper casing 43 (see FIG. 3 ). In addition, a gap C3 is formed between the lower surface 47 b of the impeller 47 and the upper surface 42 a of the lower case 42 (see FIG. 3 ). The clearances C2 and C3 are set to predetermined values in accordance with the required efficiency of the fuel pump 3 similarly to the clearance C1 described above.

Here, the motor unit 30 and the pump unit 40 are covered by the housing case 20 . The housing case 20 is a substantially cylindrical member made of iron or the like, and is formed by, for example, cutting a seamless pipe.

The upper end portion of the housing case 20 constitutes a caulking portion 22 , and is caulked to a step portion 30 c formed on the motor unit 30 .

(protrusion)

The housing case 20 has a protruding portion 21 curvedly extending inwardly from the lower end portion of the housing case 20 . The protruding portion 21 is an inner flange portion formed on the lower end of the casing 20 by cutting a seamless steel pipe to form the main body of the casing 20 , and then bending with a press, for example. The protruding portion 21 is integrally formed with the housing shell. In addition, the root portion 21 b of the protruding portion 21 is connected to the end portion of the housing case 20 .

The inner diameter of the front end portion 21 a of the protruding portion 21 is formed slightly larger than the outer diameter of the side portion 48 b of the stepped portion 48 formed on the lower case 42 . Therefore, the side portion 48 b of the lower case 42 is disposed on the inner diameter side of the front end portion 21 a of the protruding portion 21 .

An angle ring 46 is provided between the step 48 of the pump housing 45 and the protrusion 21 of the housing housing 20 . The corner ring 46 is a member having a substantially rectangular cross-section and made of a material excellent in oil resistance, such as fluororubber. The axial thickness of the angle ring 46 is set to be smaller than the axial height of the stepped portion 48 formed on the pump housing 45 .

(upper cup shell)

The upper cup 25 fitted on the fuel pump 3 is a bottomed cylindrical member made of a resin excellent in oil resistance, and is formed by, for example, injection molding.

Therefore, an attachment portion 61 of the liquid level detector 60 is formed on the upper side of the upper cup 25 . The attachment portion 61 is a plate-shaped member formed to extend radially outward. The mounting portion 61 is simultaneously molded by injection molding when the upper cup 25 is formed. The liquid level detector 60 is fixed to the mounting portion 61 by fitting or the like.

The upper cup 25 has a cylindrical portion 24 fitted on the fuel pump 3 . The cylindrical portion 24 includes a large-diameter portion 26 disposed on the lower side and a small-diameter portion 27 disposed on the upper side.

On the outer peripheral surface of the large-diameter portion 26 of the cylindrical portion 24 , an engaging convex portion 25 a is formed at a position corresponding to the engaging hole provided in the engaging piece 15 a of the flange unit 4 . The engaging protrusions 25 a of these upper cups 25 engage with the engaging pieces 15 a of the flange unit 4 , so that the upper cup 25 and the flange unit 4 are integrated.

A fuel flow path unit 52 through which fuel discharged from the fuel pump 3 flows is provided inside the cylindrical portion 24 of the upper cup 25 . The fuel channel unit 52 has a substantially L-shaped cross section and is provided in a range from the upper end surface of the small-diameter portion 27 of the cylindrical portion 24 to the outer peripheral surface of the cylindrical portion 24 .

In addition, a pressure regulator 76 is provided on the inner side of the small-diameter portion 27 of the upper cup 25 on the opposite side to the check valve 74 across the center axis O. The pressure regulator 76 is a member for maintaining the fuel pressure in the fuel flow channel unit 52 constant. When excess fuel pressure is generated in the fuel flow channel unit 52 , the pressure regulator 76 discharges the fuel in the fuel flow channel unit 52 to the tank unit 11 .

(flange unit)

The fuel supply device 1 includes a flange unit 4 disposed on the lower side of the fuel pump 3 and attached to the bottom wall 2 b of the fuel tank 2 . The flange unit 4 is a member made of resin or the like excellent in oil resistance, and is formed by, for example, injection molding.

The flange unit 4 includes a substantially disc-shaped flange portion 12 , an engaging portion 15 formed above the flange portion 12 , and a unit main body 10 formed below the flange portion 12 .

An annular portion 13 is formed at a portion of the flange portion 12 corresponding to the opening portion 2 a of the fuel tank 2 . By attaching the flange portion 12 to the fuel tank 2 , the portion below the flange portion 12 is exposed to the outside of the fuel tank 2 . In addition, the portion above the flange portion 12 is immersed in the fuel in the fuel tank 2 . A sealing member (not shown) made of rubber or the like is provided between the flange portion 12 and the bottom wall 2 b of the fuel tank 2 , so that the sealing performance between the fuel supply device 1 and the fuel tank 2 can be ensured reliably.

An engaging portion 15 is provided on the upper side of the flange portion 12, and the engaging portion 15 engages with an engaging convex portion 25a formed on the upper cup 25 to be described later. The engaging portion 15 is formed in a substantially circular shape when viewed from the axial direction. Engaging pieces 15 a protruding upward are formed at a plurality of positions (four positions in the present embodiment) on the periphery of the engaging portion 15 . The engaging piece 15a is formed so as to be elastically deformable in a direction in which the diameter of the front end side increases. In addition, an engaging hole capable of engaging with an engaging convex portion 25 a formed on the upper cup 25 is formed in the engaging piece 15 a. The flange unit 4 and the upper cup 25 can be fixed by fitting the upper cup 25 with the engaging portion 15 (snap fit).

The unit main body 10 is formed in a cylindrical shape with a bottom, and is fitted over the fuel pump 3 from the lower side of the fuel pump 3 . The inner peripheral surface 10 a of the unit main body 10 is set to have a larger diameter than the outer diameter of the fuel pump 3 . In addition, a gap is formed between the inner peripheral surface 10 a of the unit main body 10 and the outer peripheral surface of the fuel pump 3 . This gap is used to form a fuel return flow path that communicates the pressure regulator 76 with the tank unit 11 .

A connector 14 is integrally formed on the unit main body 10 . The connector 14 is a cylindrical member having a bottom, and has a connector fitting surface opened radially outward.

Connector terminals 34 are provided inside the connector 14 . One end side 34 a of the connector terminal 34 protrudes toward the inside of the connector 14 . An external connector (not shown) electrically connected to an external power source (not shown) is connected to one end side 34 a of the connector terminal 34 .

In addition, the other end side 34 b of the connector terminal 34 protrudes toward the upper side of the flange portion 12 . The wire harness 6 is connected to the other end side 34b of the connector terminal 34 to supply power to the motor unit 30 and the liquid level detector 60 from an external power source.

A space is formed inside the unit body 10 by the inner peripheral surface 10 a and the bottom surface 10 b of the unit body 10 . This space functions as the storage tank portion 11 in which fuel is stored. Also, formed outside the unit main body 10 are a filter inlet pipe (not shown) communicating with the tank portion 11 to constitute a fuel flow path, a filter outlet pipe 51 , and a fuel outlet pipe 57 .

The filter inlet pipe and the filter outlet pipe 51 communicate with an unillustrated filter unit provided separately from the fuel supply device 1 . The fuel accumulated in the tank unit 11 is introduced into the filter unit through the filter introduction pipe, and is discharged after being filtered.

Then, the fuel pump 3 sucks fuel from the fuel suction port 41 of the pump unit 40 via the filter discharge pipe 51 . Next, the fuel flows through the pump housing 45 to be pressure-fed to the upper side of the electric motor unit 30 , flows through the fuel flow path unit 52 , and is conveyed to an internal combustion engine (not shown) through a fuel take-out pipe 57 .

(base part)

A base portion 65 is formed inside the unit main body 10 . The base portion 65 is formed by reducing the diameter of the lower side of the inner peripheral surface 10 a of the unit main body 10 . In the present embodiment, the lower side of the inner peripheral surface 10 a of the unit main body 10 is reduced in diameter to form the tank portion 11 . Furthermore, the base portion 65 is formed by the tank portion 11 . After the fuel pump 3 is placed on the base portion 65, the upper cup 25 is put on from the upper side of the fuel pump 3, and the upper cup 25 is fixed to the flange unit 4, whereby the fuel pump 3 is flanged. Unit 4 supports.

The inner diameter of the base portion 65 is set to be larger than the inner diameter of the front end portion 21 a of the protruding portion 21 and smaller than the outer diameter of the housing case 20 . The inner diameter of the base portion 65 is set as described above, and the upper surface 65 a of the base portion 65 is brought into contact with the root portion 21 b of the protruding portion 21 to mount the fuel pump 3 on the flange unit 4 .

In addition, as described above, the protruding portion 21 is formed by bending the lower end portion of the housing case 20 , and therefore, the root portion 21 b of the protruding portion 21 is connected to the end portion of the housing case 20 . Therefore, the intensity|strength of the front-end|tip part 21b of the protrusion part 21 is higher than the intensity|strength of the front-end part 21a of the protrusion part 21. As shown in FIG. Therefore, it is desirable to bring the upper surface 65 a of the base portion 65 into contact with the root portion 21 b of the protruding portion 21 as described above.

(Effect)

According to the present embodiment, when the fuel pump 3 is placed in the flange unit 4 , the fuel pump 3 is supported by the flange unit 4 through the protruding portion 21 of the housing case 20 . Therefore, even if an external force such as a reaction force of the discharge pressure is generated, the external force is not directly transmitted to the resin pump casing 45 . Thereby, the external force transmitted to the pump case 45 can be relaxed, so that the deformation of the pump case 45 can be suppressed, and the gaps C1 , C2 , and C3 between the impeller 47 and the pump case 45 can be maintained. Thus, deformation of the pump housing 45 formed of resin and contact between the impeller 47 and the inner surface of the pump housing 45 can be suppressed, and a decrease in efficiency of the fuel pump 3 due to an increase in sliding resistance can be prevented.

In addition, since the pump case 45 is formed of resin, the pump case 45 can be formed at a lower cost than when the pump case 45 is formed of metal by, for example, aluminum die molding. Therefore, a low-cost fuel supply device 1 can be provided.

In addition, according to the present embodiment, when the fuel pump 3 is placed in the flange unit 4 , the base portion 65 of the flange unit 4 comes into contact with the protruding portion 21 of the housing case 20 . Therefore, the base portion 65 is not in direct contact with the pump housing 45 , but can support the fuel pump 3 via the protruding portion 21 . Thereby, even if an external force such as a reaction force of the discharge pressure is generated, the external force is not directly transmitted from the base portion 65 to the pump case 45 . As a result, deformation of the pump casing 45 can be suppressed, and clearances C1, C2, and C3 between the impeller 47 and the pump casing 45 can be maintained. Accordingly, deformation of the pump housing 45 formed of resin and contact between the impeller 47 and the inner surface 44a of the pump housing 45 can be reliably suppressed, and damage to the fuel pump 3 due to an increase in sliding resistance can be effectively prevented. Reduced efficiency.

In addition, in this embodiment, the root portion 21b of the protruding portion 21 is supported by the lower end portion of the housing case 20 , and thus has higher strength than the front end portion 21a of the protruding portion 21 . That is, according to the fuel supply device 1 of the present embodiment, since the base portion 65 supports the pump housing 45 via the root portion 21 b of the strong protrusion 21 , deformation of the protrusion 21 can be suppressed. Thus, deformation of the pump housing 45 formed of resin and contact between the impeller 47 and the inner surface 44a of the pump housing 45 can be suppressed, and a reduction in efficiency of the fuel pump 3 due to an increase in sliding resistance can be prevented.

Furthermore, according to the present embodiment, even if an external force such as reaction force of the discharge pressure is generated, the external force can be absorbed by the corner ring 46 (seal member) provided between the pump housing 45 and the protruding portion 21 . Therefore, the external force transmitted to the pump housing 45 can be relaxed. Therefore, deformation of the pump housing 45 formed of resin and contact between the impeller 47 and the inner surface 44a of the pump housing 45 can be suppressed, and efficiency reduction of the fuel pump 3 due to an increase in sliding resistance can be prevented. In addition, stable performance of the fuel pump 3 can be maintained for a long period of time.

In addition, according to the present embodiment, the protruding portion 21 can be firmly formed, and thus deformation of the protruding portion 21 can be suppressed. Therefore, deformation of the pump housing 45 formed of resin and contact between the impeller 47 and the inner surface 44a of the pump housing 45 can be reliably suppressed, and a decrease in efficiency of the fuel pump 3 due to an increase in sliding resistance can be prevented. . In addition, the motor unit 30 and the pump unit 40 can be reliably integrated. In addition, since the corner ring 46 is firmly in close contact with the pump housing 45 and the protruding portion 21, the sealing performance can be improved.

In addition, according to the present embodiment, the above configuration is applied to the fuel supply device 1 attached to the bottom wall 2 b of the fuel tank 2 . In particular, since the flange unit 4 is provided on the lower side of the fuel pump 3, it can be ideally used in a so-called undermount type fuel supply device 1 . Therefore, in the fuel supply device 1 fixed to the lower side of the fuel tank 2, deformation of the pump housing 45 formed of resin and contact between the impeller 47 and the inner surface 44a of the pump housing 45 can be reliably suppressed, and A reduction in the efficiency of the fuel pump 3 due to an increase in sliding resistance can be prevented.

(Second embodiment, top-mounted fuel supply device)

Next, a second embodiment of the present invention will be described using FIGS. 5 to 8 . In the first embodiment, the case where the present invention is applied to the so-called undermount type fuel supply device 1 in which the fuel tank is attached to the bottom of the fuel tank 2 has been described. However, in the second embodiment, a case where the present invention is applied to a so-called top-mounted fuel supply device 1 in which a fuel tank is attached to an upper portion of a fuel tank 2 will be described. In this point, the second embodiment of the present invention is different from the first embodiment of the present invention. In addition, detailed descriptions of components that are the same as those of the first embodiment of the present invention and the modification of the first embodiment of the present invention will be omitted.

A fuel supply device 1 according to a second embodiment of the present invention is inserted into an opening 2 a formed in an upper wall 2 c (see FIG. 6 ) of a fuel tank 2 and attached to the upper wall 2 c of the fuel tank 2 . The fuel supply device 1 includes: a fuel pump 3 arranged in the fuel tank 2 ; a lower cup 100 ("housing") which is set on the fuel pump 3 and supports the fuel pump 3; Flange unit 4 for wall 2c.

(flange unit)

The fuel supply device 1 includes a flange unit 4 disposed above the fuel pump 3 and attached to the upper wall 2 c of the fuel tank 2 .

An annular portion 13 is formed at a portion of the flange portion 12 corresponding to the opening portion 2 a of the fuel tank 2 . By attaching the flange portion 12 to the fuel tank 2 , a portion above the flange portion 12 is exposed to the outside of the fuel tank 2 . In addition, the portion below the flange portion 12 is immersed in the fuel in the fuel tank 2 .

An engaging portion 15 is provided on the lower side of the flange portion 12 to engage with an engaging convex portion 25 a formed on the lower cup 100 to be described later. Engagement pieces 15 a protruding downward are formed at a plurality of positions (four positions in the present embodiment) on the periphery of the engagement portion 15 . By fitting the lower cup 100 with the engaging portion 15 , the flange unit 4 and the lower cup 100 can be fixed.

The unit main body 10 is formed in a cylindrical shape with a bottom, and is fitted over the fuel pump 3 from the lower side of the fuel pump 3 . A fuel flow path unit 52 is formed inside the unit main body 10 .

The fuel channel unit 52 communicates with the pressure regulator 76 , the check valve 74 , and the fuel take-out pipe 57 .

(lower cup shell)

The lower cup 100 fitted on the lower side of the fuel pump 3 is a cylindrical member having a bottom made of resin excellent in oil resistance, and is formed by, for example, injection molding.

A mounting portion 61 of the liquid level detector 60 is formed on the radially outer side of the lower cup 100 . The attachment portion 61 is a plate-shaped member formed to extend radially outward. The mounting portion 61 is simultaneously molded by injection molding when the upper cup 25 is formed.

In addition, a filter unit 90 is installed on the lower side of the lower cup 100 .

The filter unit 90 communicates with the fuel intake port 41 via the filter discharge pipe 51 . The fuel in the fuel tank 2 is introduced into the fuel suction port 41 of the pump unit 40 through the filter unit 90 and the filter discharge pipe 51 . Next, the fuel flows through the pump housing 45 to be pressure-fed to the upper side of the electric motor unit 30 , flows through the fuel flow path unit 52 , and is conveyed to an internal combustion engine (not shown) through a fuel take-out pipe 57 .

(base part)

In addition, as shown in FIGS. 7 and 8 , a base portion 65 is formed inside the lower cup 100 . The base portion 65 is formed by reducing the diameter of the lower side of the inner peripheral surface 100 a of the unit main body 100 . After the fuel pump 3 is placed on the base portion 65 of the lower cup 100 , the flange unit 4 is fitted from the upper side of the fuel pump 3 and the flange unit 4 is fixed to the lower cup 100 . As a result, the casing case 20 of the fuel pump 3 is supported in a state of being in contact with the base 65 of the lower cup 100 .

(Effect of the second embodiment)

According to the present embodiment, the above configuration is applied to the fuel supply device 1 attached to the upper wall 2c of the fuel tank 2 . The above structure is ideally used in a so-called top-mounted fuel supply device 1 in which the flange unit 4 is provided above the fuel pump 3 . Therefore, in the fuel supply device 1 fixed to the upper side of the fuel tank 2, deformation of the pump housing 45 formed of resin and contact between the impeller 47 and the inner surface 44a of the pump housing 45 can be reliably suppressed, and A reduction in the efficiency of the fuel pump 3 due to an increase in sliding resistance is prevented.

In addition, the present invention is not limited to the above-mentioned embodiments.

In the first embodiment of the present invention, the tank portion 11 is formed by reducing the diameter of the lower side of the inner peripheral surface 100 a of the unit body 10 , and the base portion 65 is formed of the tank portion 11 . However, the base portion 65 may also be formed by providing a reduced-diameter portion of the inner peripheral surface 10 a separately from the tank portion 11 . However, the first embodiment of the present invention is superior in that the space of the flange unit 4 is effectively used to provide the base portion 65 .

In the first embodiment of the present invention, the protruding portion 21 is formed by bending the lower end portion of the housing case 20 or the like. However, it is also possible to connect the protrusion to the end of the housing case 20 by welding or the like, for example, after forming the protrusion as another part. However, since the protruding portion 21 is integrally formed with the housing case 20 , the protruding portion 21 can be formed at low cost, and the first embodiment of the present invention has an advantage in terms of excellent strength.

In the first embodiment of the present invention, the corner ring 46 is used as the sealing member arranged between the pump housing 45 and the protruding portion 21 . However, the sealing member is not limited to the corner ring 46, and may be an O-ring. In addition, when assembling the casing case 20 to the fuel pump 3 , a sealing member may be arranged between the pump case 45 and the protruding portion 21 by applying silicone or the like to the stepped portion 48 of the pump case 45 .

Industrial availability

According to the present invention, deformation of the pump housing formed of resin and contact between the impeller and the inner surface of the pump housing can be suppressed, and a reduction in efficiency of the fuel pump due to an increase in sliding resistance can be prevented. In addition, the pump housing can be formed at low cost, and a low-cost fuel supply device can be provided.

Symbol Description

1 fuel supply device

2 fuel tanks

2b bottom wall

3 fuel pump

4 Flange unit (housing)

20 shell shell

21 protrusion

21b root

30 Motor department

40 pump department

46 Angle ring (sealing member)

65 base part

Claims (6)

1. fuel supplying device comprises:

Petrolift, this petrolift is disposed in the fuel tank, and the fuel in the described fuel tank is drawn the back carry towards internal-combustion engine pressure; And

Housing, this housing supports described fuel tank, and is installed on the wall of described fuel tank,

It is characterized in that,

Described petrolift comprises:

Motor part;

Pump portion, this pump portion is located at the bottom of described motor part; And

Metal case body, this case body will cover around described motor part and the described pump portion,

Described pump portion has the pump case that is formed by resin,

Be formed with the protuberance with described pump case butt in the inboard of described case body,

Described petrolift is supported by described housing via described protuberance.

2. fuel supplying device as claimed in claim 1 is characterized in that,

In described housing, be provided with the base portion that described pump case is supported via described protuberance.

3. fuel supplying device as claimed in claim 2 is characterized in that,

Described base portion supports described pump case via the root of described protuberance.

4. as each described fuel supplying device in the claim 1 to 3, it is characterized in that,

Between described pump case and described protuberance, be provided with sealing component.

5. as each described fuel supplying device in the claim 1 to 4, it is characterized in that,

Described lip part is the inward flange portion that is formed at the lower end of described case body.

6. as each described fuel supplying device in the claim 1 to 5, it is characterized in that,

Described housing is installed on the diapire of described fuel tank, uploads in the described base portion that is formed at described housing and is equipped with described petrolift.

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