SPECIFICATION FUEL SUPPLY SYSTEM

BACKGROUND OF THE INVENTION

Field of the Invention

The present invention relates to a fuel supply system that is held at the opening portion of the fuel tank of a motorcycle or the like and works for transmitting fuel to the outside of the fuel tank.

Description of the Related Art

In general, the fuel supply system in a conventional motorcycle is configured with a pump unit, a motor unit that drives the pump unit, and a flange unit that holds a stator unit included in the motor unit and is fixed on the fuel tank in such a way as to cover the opening portion provided in the fuel tank. In recent years, in response to a demand for downsizing and weight saving thereof, there have been offered various kinds of proposals.

In addition, there has been proposed a fuel supply system in which there are integrally molding-processed a discharging pipe that transmits, to an engine, pressurized fuel discharged from a fuel supply system; a connector connected with an external electric circuit; and a flange unit that mounts, on the fuel tank, a motor unit for driving a pump unit, and in which, in the molding-processing process, a stator core on which a coil is wound is integrally insertion-molded (e.g., refer to Japanese Patent Application Laid-Open No. 2009-222055 and FIG. 1 thereof).

A conventional fuel supply system is configured as described above; however, because motorcycles range from a 50- cc moped to a 2000-cc motorcycle and the respective fuel supply amounts of the fuel supply systems for these motorcycles correspond to the engine capacities and differ from one another, it is required to change the specifications of the stator unit, the motor unit, and the pump unit, in accordance with the supply amount.
However, in a conventional fuel supply system, the flange unit and the motor unit are integrally formed; thus, there has been a problem that it is required to prepare many kinds of molding-integrated flange units in accordance with the engine capacity.

SUMMARY OF THE INVENTION

The present invention has been implemented in order to solve the foregoing problems; the objective thereof is to provide a fuel supply system that can not only deal with many kinds of engine capacities but also securely supply electric power to a motor unit by making it possible to couple a housing in which a pump unit and the motor unit are integrally molded with a flange unit in which a discharging pipe and a connector are integrally molded so that, even when the housing changes in accordance with the specification, the flange unit can commonly be utilized.

In a fuel supply system, according to the present invention, that is configured with a pump unit, a motor unit that drives the pump unit, and a flange unit that holds the pump unit and the motor unit and is fixed on a fuel tank in such a way as to cover an opening portion provided in the fuel tank and that transmits a fuel inside the fuel tank to the outside of the fuel tank through a discharging pipe, there are integrally formed, in a flange of the flange unit, the discharging pipe, an electric power supply means for supplying electric power to the motor unit, and a flange-side coupling portion provided in an extending manner in order to hold the pump unit and the motor unit; and in a housing, there are integrally formed a stator unit in which a coil and a stator core included in the motor unit are molded and a housing-side coupling portion that is coupled with the flange-side coupling portion.

According to the present invention, there can be provided a fuel supply system that can not only deal with many kinds of engine capacities but also securely supply electric power to a motor unit by coupling a housing in which a pump unit and the motor unit are integrally molded with a flange unit in which a discharging pipe and a connector are integrally molded so that, even when the housing changes in accordance with the specification, the flange unit can commonly be utilized.

The foregoing and other object, features, aspects, and advantages of the present invention will become more apparent from the following detailed description of the present invention when taken in conjunction with the accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a longitudinal cross-sectional view of a fuel supply system according to Embodiment 1 of the present invention;

FIG. 2 is an enlarged view of the principal part in FIG.1;

FIG. 3 is a partially broken cross-sectional view of a flange-side coupling portion in FIG. 1;

FIG. 4 is a perspective view of a housing-side coupling portion in FIG. 1;

FIG. 5 is a longitudinal cross-sectional view of another example according to Embodiment 1 of the present invention;

FIG. 6 is an enlarged view of the principal part of a fuel supply system according to Embodiment 2 of the present invention;

FIG. 7 is a side view of a flange-side coupling portion in FIG. 6;

FIG. 8 is a perspective view of a housing-side coupling portion in FIG. 6; and

FIG. 9 is a longitudinal cross-sectional view of a fuel supply system according to Embodiment 3 of the present invention.

DETAILED DESCRIPTION OF THE PREFERRRED EMBODIMENTS
Embodiment 1

FIG. 1 is a longitudinal cross-sectional view of a fuel supply system according to Embodiment 1 of the present invention;

FIG. 2 is an enlarged view of the principal part in FIG. 1; FIG. 3 is a partially broken cross-sectional view of a flange- side coupling portion;

FIG. 4 is a perspective view of a housing-side coupling portion; and

FIG. 5 is a longitudinal cross-sectional view of another example.

The configuration of a fuel supply system 100 according to Embodiment 1 of the present invention will be explained with reference to FIGS. 1 through 4.

For example, in a motorcycle, the fuel supply system 100 is mounted in a suspending manner at an opening portion 2a of a fuel tank 2 that stores a fuel 1, and is configured with a pump unit 20, a motor unit 30, which is a driving source for the pump unit 20, and a flange unit 4 0 that serves as a mounting member for mounting the fuel supply system 100 on the fuel tank 2.

The pump unit 20 configured in such a way that an impeller 5 is contained in a pump base 3 and a pump cover 4; the pump in the fuel supply system 100 according to embodiments of the present invention is a so-called turbine pump type.

The impeller 5 is formed in a disk shape and in a pivotable manner; the impeller 5 is contained in the pump base 3 and the pump cover 4 in such a way that the pump base 3 and the pump cover 4 flank the front and rear sides thereof, the center portion thereof engages with a shaft 9c of a rotor unit 9, described later, and it is supported by a bearing 6 adhered to the center portion of the pump cover 4. The pump base 3 and the pump cover 4 are inserted in a pump holder 18; the pump holder 18 is fixed in such a way as to engage, by means of a snap fit, with a hole 10c provided in one end of a housing 10, described later. In one end, of the pump cover 4, which faces the fuel tank 2 (which faces the bottom end of FIG. 1), there is disposed an inlet 4a that takes in the fuel 1 in the fuel tank 2.

C-shaped pump flow paths 20a are formed at the circumferential end portions of both sides of the impeller 5 and at the respective sides, of the pump base 3 and the pump cover 4, which face the impeller 5; the fuel 1 in the fuel tank 2 is filtered by an intake filter 7 coupled with the pump cover 4 and flows into the pump unit 20 through the inlet 4a; due to the rotation of the impeller 5, the pressure of the fuel 1 is raised as it flows through the pump flow path 20a; then, the fuel 1 is transmitted to the motor unit 30 in a pressurized manner.

The fuel 1 transmitted in a pressurized manner from the pump unit 20 to the motor unit 30 passes through a flow path between the rotor unit 9 and a stator core 8a, described later (refer to FIG. 2), and is supplied to a fuel path lid through a communication path 11f formed in the flange unit 40 (refer to FIG. 1).

In the motor unit 30, a brushless motor is adopted; the brushless motor is configured with a stator unit 8 including the stator core 8a formed of a magnetic material and a coil 8b wound around the stator core 8a and a rotor unit 9 including a cylindrical rotor core 9a, a magnet 9b adhered on the circumferential surface of the rotor core 9a, and a shaft 9c inserted into the center of the rotor core 9a.

The rotor unit 9 is pivotably disposed inside the inner circumference of the stator core 8a; the shaft 9c is pivotably supported by the bearing 6 (illustrated in FIG. 1).

Additionally, the magnet 9b is a plastic magnet formed in a cylindrical shape by kneading magnetic powder into a thermoplastic resin material such as PPS (polyphenylene sulfide) , and is magnetized in such a way as to alternately form different magnetic poles in a rotation direction on the outer circumferential surfaces that face the stator core 8a.

The stator core 8a (FIG. 2) is formed by engaging magnetic steel plates, which are laminated in the axis direction thereof, with one another in a swaging manner; there are formed in the circumferential direction, teeth 8c, for example, six pieces of teeth 8c that protrude toward the center of the motor unit 30 and are spaced evenly angled from one another. An insulator 8d made of an insulating material is provided in such a way as to cover the surface of the stator core 8a; the coil 8b is wound around the insulator 8d.

The coil 8b is supplied with a three-phase alternating current by an unillustrated control apparatus and connected, for example, in a star shape in such a way as to generate a rotating magnetic field in the circumferential direction, and connected to three load terminals 12a, 12b, and 12c, described later (FIG. 2) .

The housing 10 is formed, for example, of a thermoplastic resin such as a polyacetal resin; in the housing 10, there are integrally insertion-molded the stator core 8a, the coil 8b, and the load terminals 12a, 12b, and 12c that are disposed around the circumference of a housing-side coupling portion 10a, described later, and are connected with the coil 8b; because the housing 10 is filled with a resin material, the fuel does not directly make contact with the coil 8b, whereby the coil 8b can be prevented from corroding even when a deteriorated fuel or a low-quality fuel is utilized.

At the portion (the upper portion in FIG. 1) of the housing 10 that faces the pump unit 20, there is provided the housing-side coupling portion 10a formed in such a way as to be attachable to and detachable from a flange-side coupling portion lie, described later, of the flange unit 40; in the inner circumference of the housing-side coupling portion 10a, engagement recesses l0al are spaced approximately 120° apart from one another (refer to FIG. 4).

The flange unit 40 includes a flange 11 and the like; in the flange 11, a discharging pipe 11a, which transmits pressurized fuel to the engine (unillustrated) through an unillustrated fuel pipe, and a connector unit lib, which is an electric power supply means having a terminal 11bl for supplying electric power to the coil 8b, are integrally molded with a thermoplastic resin material such as a PPS resin or a POM resin; the flange 11 is formed in the shape of a tablet that is perpendicular to the axis direction (the vertical direction in FIG. 1), inserted into the circular opening portion 2a of the fuel tank 2, and fixed to the fuel tank 2 by being tighten with an unillustrated fixing metal member or the like while a packing 15 is inserted between the plain portion thereof and the outer surface of the fuel tank 2. In the central portion of the flange 11, there is formed the communication path 11f for communicating the fuel filtered with a discharging filter 16, described later, to the fuel path lid.

A check valve 13 is disposed in the fuel path lid. The check valve 13 is configured with a valve body 13a, a valve seat 13, and a valve spring 13c; as the valve spring 13c, a coil spring is utilized; the valve spring 13c is contracted when the check valve 13 is completely closed. The valve body 13a makes contact with the valve seat 13b due to elastic force exerted by the spring 13c; while the fuel supply system 100 is operated, the force that is produced by the pressure of the fuel discharged from the pump unit 20, acts on the valve body 13a, and heads for the downstream side (the left side in FIG. 1) of the fuel path lid surpasses the elastic force exerted by the spring 13c; accordingly, the valve body 13a leaves the valve seat 13b and hence the fuel flows into the discharging pipe 11a.

In contrast, while the fuel supply system 100 is stopped, the valve body 13a makes contact with the valve seat 13b due to the elastic force exerted by the spring 13c; thus, the fuel path lid is shut off by the check valve 13. Therefore, the fuel inside the fuel path lid at the downstream side of the check valve 13 and the fuel inside the unillustrated fuel pipe connected with the discharging pipe 11a do not return to the fuel tank 2 through the fuel supply system 100 but remain therein, and the pressure of the fuel pressurized is retained. Accordingly, when the engine is started next time, the fuel is immediately supplied to the engine; therefore, it is made possible to start the engine rapidly.

Furthermore, a regulator 14 is disposed at a position halfway in the fuel path lid, which is at the downstream side of the check valve 13, in such a way as to face the fuel tank 2 (downward in FIG. 1).

The regulator 14 is configured with a valve body 14a, a valve seat 14b, and a valve spring 14c. As the valve spring 14c, a coil spring is utilized; the valve spring 14c is contracted when the regulator 14 is completely closed. The regulator 14 is to adjust the pressure of the fuel, transmitted from the fuel supply system 100, at a desirable pressure. Here, the desirable pressure denotes the fuel pressure required by the engine. In the regulator 14, the contact condition and the separation condition between the valve body 14a and the valve seat 14b are determined based on the magnitude relationship between the force exerted on the valve body 14a by the fuel pressure and the elastic force exerted by the spring 14c.

That is to say, in the case where the fuel pressure inside the fuel path lid is the same as or lower than the desirable pressure, the valve body 14a makes contact with the valve seat 14b, thereby closing the regulator 14. In the case where the fuel pressure inside the fuel path l1d exceeds the desirable pressure, the valve body 14a leaves the valve seat 14b, thereby opening the regulator 14, and then part of the fuel inside the fuel path l1d returns to the inside of the fuel tank 2, i.e. to a low-pressure region; as a result, the fuel pressure inside the fuel path l1d is maintained at the desirable pressure. In the portion, of the housing 10 for the regulator 14, which faces the fuel tank 2, a through-hole 10b is provided at a position corresponding to the position of the regulator 14; the fuel discharged from the regulator 14 passes through the through-hole 10b and is returned to the inside of the fuel tank 2.

As is clear from FIGS. 1 through 3, in the flange 11 of the flange unit 40, there is provided in an extending manner the flange-side coupling portion l1e, with respect to which the housing-side coupling portion 10a of the housing 10 is detachably and attachably formed; on the outer circumference of the flange-side coupling portion l1e, there are arranged engagement protrusions 11el that are spaced approximately 120° apart from one another, and these engagement protrusions 11el engage, by means of snap fits, with the corresponding engagement recesses l0al of the housing-side coupling portion 10a described above.

Additionally, on the outer circumference of the flange- side coupling portion lie, there are arranged power-source terminals 17a, 17b, and 17c that each are electrically connected with the terminal 11bl and are electrically connected with the load terminals 12a, 12b, and 12c when the flange-side coupling portion lie is coupled with the housing-side coupling portion 10a (refer to FIG. 3) .

Reference character 15a denotes an 0-ring, which is an airtight member; the O-ring is to hold the airtightness of the coupling portion between the flange-side coupling portion l1e and the housing-side coupling portion 10a.
Inside the flange-side coupling portion l1e, there is disposed the discharging filter 16 that filters the fuel 1 to be transmitted to the outside of the fuel tank 2. The discharging filter 16 is a filtering member formed in the shape of a chrysanthemum-type cylinder or a roller and is disposed to be concentric with the cylindrical rotor unit 9; the fuel that has passed through the path between the stator core 8a and the rotor unit 9 flows into the discharging filter 16 along the arrows A, B, and C (FIG. 2) in that order; in other words, the fuel flows into the discharging filter 16 uniformly in the circumferential direction thereof; therefore, there is demonstrated an effect that the pressure loss is reduced.

The communication path 11f is disposed in the approximately center portion of the discharging filter 16, and because the rotor unit 9, the discharging filter 16, and the communication path 11f are formed in a straight manner, the fuel smoothly passes through them; that is why the pressure loss is small. In addition, as the filtering member, there is utilized an unwoven fabric, which is superior to a net-like
filter in the filtering performance.
Next, there will be explained the operation of the fuel supply system 100 configured as described above. An unillustrated control circuit supplies driving currents to the coil 8b by way of the terminal 11bl of the connector unit lib, the power-source terminals 17a, 17b, 17c, and the load terminals 12a, 12b, and 12c, so that the teeth 8c on the surface, of the stator unit 8, which faces the rotor unit 9 generate a rotating magnetic field.

The magnet 9b disposed in the rotor unit 9 rotates keeping track of the magnetic poles and the impeller 5 engaged with the shaft 9c of the rotor unit 9 also rotates, so that a swirling flow is produced in the C-shaped pump flow path 20a.

The fuel 1 in the fuel tank 2 flows into the pump unit 20 through the inlet 4a provided in the pump cover 4 through the intake filter 7; due to the rotation of the impeller 5, the pressure of the fuel 1 is raised as it flows through the pump flow path 20a; then, the fuel 1 is transmitted to the motor unit 30 (upward from the pump unit 20 in FIG. 1) in a pressurized manner.

The fuel 1 transmitted in a pressurized manner to the motor unit 30 passes through a flow path between the rotor unit 9 and the stator core 8a, flows into the communication path 11f formed in the flange unit 40 by way of the fuel filter 16, and is further supplied to the fuel path lid. The pressure of the fuel that has flown into the fuel path lid is regulated at a desirable pressure by the regulator 14 and is discharged from the discharging pipe 11a to an unillustrated internal combustion engine such as a vehicle engine.

While the fuel supply system 100 is stopped, the fuel in the fuel path lid at the downstream side and an unillustrated fuel pipe connected with the discharging pipe 11a is held by the check valve 13 at a pressurized pressure.

FIG. 5 illustrates another example for explaining an effect of the present invention.

The foregoing fuel supply system illustrated in FIGS. 1 through 4 is applied to a 50-cc moped and a vehicle having the engine capacity ranging, for example, up to 250 cc; however, the fuel supply system illustrated in FIG. 5 is applied to a middle-size vehicle having the engine capacity of 400 cc through a large-size vehicle having the engine capacity of 2000 cc.

In FIG. 5, reference numeral 80 denotes a stator unit, and the outer diameter thereof is approximately the same as that of the foregoing stator unit 8; however, the stator unit 80 is formed in such a way that the overall length thereof is larger than that of the stator unit 8. Reference numeral 90 denotes a rotor unit, and the outer diameter thereof is approximately the same as that of the foregoing rotor unit 9; however, the rotor unit 90 is formed in such a way that the overall length thereof is larger than that of the rotor unit 9.

A housing 100 and a stator core are formed in such a way that the overall lengths thereof are longer, and they are integrally molded with a resin.

The fuel supply system configured as described above is formed in such a way that the stator unit 80 and the rotor unit 90 thereof are longer than the foregoing stator unit 8 and rotor unit 9, respectively; therefore, when an unillustrated control circuit supplies a driving current to the coil of the stator unit 80 by way of the terminal 11bl, there becomes strong the magnetic field produced by the teeth on the surface, of the stator unit 80, which faces the rotor unit 90. As a result, the rotation torque produced by the rotor unit 90 is large and hence the rotation speed thereof can be increased; thus, the amount of fuel discharged from the discharging pipe 11a also becomes large, whereby the fuel supply system can deal with a vehicle having a large engine capacity.

As described above, in the fuel supply system according to Embodiment 1 of the present invention, by utilizing the stator unit 80 and the rotor unit 90 depending on the situation, there can be provided fuel supply systems corresponding to many kinds of engine capacities without preparing many kinds of flanges 40.
Additionally, on the outer circumference of the flange- side coupling portion l1e, there are arranged the power-source terminals 17a, 17b, and 17c, and on the inner circumference of the housing-side coupling portion 10a, there are provided the load terminals 12a, 12b, and 12c that make contact with and are electrically connected with the power-source terminals 17a, 17b, and 17c; thus, when the housing-side coupling portion 10a is inserted into the flange-side coupling portion lie, the power- source terminals 17a, 17b, and 17c and the load terminals 12a, 12b, and 12c concurrently make contact with each other, whereby electric power is securely supplied to the motor unit 30 through the connector l1b. Embodiment 2

The configuration of a fuel supply system 200 according to Embodiment 2 of the present invention will be explained.

FIG. 6 is an enlarged view of the principal part of the fuel supply system 200 according to Embodiments of the present invention; FIG. 7 is a side view of a flange-side coupling portion in FIG. 6; FIG. 8 is a perspective view of a housing- side coupling portion in FIG. 6.

In FIG. 6, only components different from those in FIG. 1 are designated by reference characters; other configurations are similar to those in Embodiment 1.

In FIG. 6, a housing 101 is formed in such a way that there are integrally insertion-molded therein the stator core 8a, the coil 8b, and load terminals 120a, 120b, and 120c that are disposed around the inner circumference of a housing-side coupling portion 101a and are electrically connected with the coil 8b.

In FIGS. 7 and 8, on the outer circumference of a flange- side coupling portion ll0e of a flange 110, there are arranged power-source terminals 170a, 170b, and 170c that each are electrically connected with the terminal 11bl (refer to FIG. 1) and are electrically connected with the load terminals 120a, 120b, and 120c, respectively, when the flange-side coupling portion ll0e is coupled with the housing-side coupling portion 101a.

On the inner circumference of the flange-side coupling portion ll0e, there are arranged engagement protrusions ll0el spaced approximately 120° apart from one another, and on the inner circumference of the housing-side coupling portion 101a, there are arranged engagement recesses l0lal spaced approximately 120° apart from one another; therefore, the motor unit 30 and the pump unit 20 (refer to FIG. 1) can robustly be fixed to the flange unit 40.

Moreover, in the fuel supply system according to Embodiment 2 of the present invention, on the outer circumference of the flange-side coupling portion ll0e, there are arranged the power-source terminals 170a, 170b, and 170c spaced approximately 120° apart from one another, and on the inner circumference of the housing-side coupling portion 101a, there are provided the load terminals 120a, 120b, and 120c, also spaced approximately 120° apart from one another but each shifted by a predetermined angle from the engagement recess l0lal, that make contact with the power-source terminals 170a, 170b, and 170c; thus, when snap fitting is performed, the elastic force produced by the housing-side coupling portion 101a is exerted on the load terminals 120a, 120b, and 120c, whereby the power-source terminals 170a, 170b, and 170c and the load terminals 120a, 120b, and 120c make contact with each other in a dynamically stabilized manner. As a result, there is demonstrated an effect that electric power is supplied to an unillustrated motor unit in a secured and balanced manner through an unillustrated connector. Embodiment 3

The configuration of a fuel supply system 300 according to Embodiment 3 of the present invention will be explained.

FIG. 9 is a longitudinal cross-sectional view of a fuel supply system according to Embodiment 3 of the present invention. Only components different from those in FIG. 1 are designated by reference characters; other configurations are similar to those in Embodiment 1.
In the foregoing fuel supply system according to Embodiment 1 or Embodiment 2 of the present invention, the engagement protrusion 11el is disposed in the flange-side coupling portion l1e and the engagement recess l0lal is disposed in the housing-side coupling portion 101a so that the engagement protrusion 11el and the engagement recess l0lal engage with each other; however, it may be allowed that, as illustrated in FIG. 9, a wire 19 is preliminarily inserted into a flange-side coupling portion 210e and an electric current is applied to the wire 19 so as to melt the flange-side coupling portion 210e so that a housing-side coupling portion 201a and the flange-side coupling portion 210e are coupled with each other in a melting manner.

In this case, after the load terminals 12a, 12b, and 12c are inserted into and electrically connected with the power- source terminals 17a, 17b, and 17c, the flange-side coupling portion 210e and the housing-side coupling portion 201a are coupled in a melting manner. When the load terminals 12a, 12b, and 12c are inserted into the power-source terminals 17a, 17b, and 17c, the housing 10 and the flange 11 are integrally formed; therefore, when melted through hot-wire welding, the flange-side coupling portion 210e and the housing-side coupling portion 201a are coupled with each other in a melting manner, whereby melting work can readily be performed.

In addition, it may be allowed that, as is the case with Embodiment 2, on the outer circumference of the flange-side coupling portion 210e, there are arranged the power-source terminals 17a, 17b, and 17c spaced approximately 120° apart from one another, and on the inner circumference of the housing-side coupling portion 201a, there are arranged the load terminals 12a, 12b, and 12c spaced approximately 120° apart from one another, so that the power-source terminals 17a, 17b, and 17c and the load terminals 12a, 12b, and 12c are coupled with each other.

Various modifications and alterations of this invention will be apparent to those skilled in the art without departing from the scope and spirit of this invention, and it should be understood that this is not limited to the illustrative embodiments set forth herein.

WHAT IS CLAIMED IS:

1. A fuel supply system comprising:

a pump unit;

a motor unit that drives the pump unit; and a flange unit that holds the pump unit and the motor unit and is fixed on a fuel tank in such a way as to cover an opening portion provided in the fuel tank, the fuel supply system transmitting a fuel inside the fuel tank to the outside of the fuel tank through a discharging pipe, wherein, in a flange of the flange unit, there are integrally formed the discharging pipe, an electric power supply means for supplying electric power to the motor unit, and a flange-side coupling portion provided in an extending manner in order to hold the pump unit and the motor unit; and in a housing, there are integrally formed a stator unit in which a coil and a stator core included in the motor unit are molded and a housing-side coupling portion that is coupled with the flange-side coupling portion.

2. The fuel supply system according to claim 1, wherein an engagement protrusion is provided in the flange-side coupling portion, and in the housing-side coupling portion, there is provided an engagement recess that engages with the engagement protrusion.
3. The fuel supply system according to claim 2, wherein, on the outer circumference of the flange-side coupling portion, there are arranged the engagement protrusions spaced approximately 120° apart from one another, and on the inner circumference of the housing-side coupling portion, there are arranged the engagement recesses spaced approximately 120° apart from one another.

4. The fuel supply system according to claim 2, wherein, on the outer circumference of the flange-side coupling portion, a power-source terminal is provided, and on the outer circumference of the housing-side coupling portion, a load terminal that makes contact with the power-source terminal is provided; and when the flange-side coupling portion is coupled with the housing-side coupling portion, the power-source terminal is electrically connected with the load terminal.

5. The fuel supply system according to claim 2, wherein, on the outer circumference of the flange-side coupling portion, there are arranged power-source terminals spaced approximately 120° apart from one another, and on the inner circumference of the housing-side coupling portion, there are arranged load terminals that are spaced approximately 120° apart from one another and make contact with the power-source terminals; and when the flange-side coupling portion is coupled with the housing-side coupling portion, the power-source terminals are electrically connected with the load terminals.

6. The fuel supply system according to claim 1, wherein coupling between the flange-side coupling portion and the flange-side coupling portion is performed through mutual melting-coupling by hot-wire welding.

7. The fuel supply system according to claim 1, wherein, in the housing, there are integrally inserted and molded the stator core, the coil, and load terminals that are arranged on the outer circumference of the housing-side coupling portion and are electrically connected with the coil.

8. The fuel supply system according to any one of claims 1 through 7, wherein, inside the flange-side coupling portion, there is disposed a discharging filter for filtering the fuel to be transmitted to the outside of the fuel tank.

9. The fuel supply system according to claim 8, wherein the discharging filter is a filtering member formed in the shape of a chrysanthemum-type or a roller-type cylinder and is disposed to be concentric with a cylindrical rotor unit that is rotated by the act of a magnetic field produced by the stator unit.

10. The fuel supply system according to claim 9, wherein the filtering member is an unwoven fabric.