| Title of Invention | FUEL SUPPLY DEVICE |
|---|---|
| Abstract | To provide a fuel supply device in which a structure of a return passageway can be simplified using a one-way valve. [Solution] A one-way valve unit 30 is attached to a return passageway (an upper return passageway 100, lower return passageway 101) for returning bubbles to a fuel tank 9 from an out-tank type fuel pump 20 arranged below the fuel tank 9. An upper end of the upper return passageway 101 is connected to a return side opening 9b formed to a bottom of the fuel tank 9. An umbrella valve 40 including an umbrella portion 42 and a support portion 41 is applied to the one-way valve unit 30. A structure is that the umbrella portion 42 deforms to provide communication through the return passageway only when pressured from the fuel pump 9. A pre-filter 50 is arranged between an upper supply passageway 200 and a lower supply passageway 201. A cock 60 capable of regulating a flow rate freely is arranged upstream of the pre-filter 50. [Selected Drawing] Fig. 2 |
| Full Text | [Document Name] Description [Title of Invention] FUEL SUPPLY DEVICE [Technical Field] [0001] The present invention relates to a fuel supply device, and particularly, to a fuel supply device in which a fuel pump for pumping fuel in a fuel tank to a fuel injector is arranged outside the fuel tank. [Background Art] [0002] In the past, fuel supply devices in which a fuel pump for pumping fuel in a fuel tank to a fuel injector is arranged outside the fuel tank have been known. In such fuel supply devices, a return passageway for returning bubbles, such as vapor gas generated in association with operation of the fuel pump, to the fuel tank is provided. [0003] Patent Literature 1 discloses a fuel supply device in which a return passageway for returning vapor to a fuel tank passes in the fuel tank and extends upward and an open end of the passageway is arranged above an oil level when the tank is full of fuel. [Citation List] [Patent Literature] [0004] [Patent Literature 1] JP-A No. 2006-1308 [Summary of Invention] [Technical Problem] [0005] However, in the fuel supply device disclosed in Patent Literature 1, a problem occurs in that, since it is necessary to arrange a long pipe member for the return passageway inside the fuel tank, a structure of the fuel tank is complicated and the production processes increase. [0006] For addressing the problem of the above past technique, an object of the present invention is to provide a fuel supply device in which a structure of a return passageway can be simplified using a one-way valve. [Solution to Problem] [0007] To achieve the object, in a fuel supply device in which fuel in a fuel tank (9) is supplied to a fuel pump (20) arranged below the fuel tank (9) through a supply passageway (200, 201), fuel is supplied to a fuel injector (19, 70) by driving the fuel pump (20), and a bubble (150) generated in the fuel pump (2 0) is returned to the fuel tank (9) through a return passageway (100, 101), a first feature of the present invention is that a one-way valve (30) permitting only passage from the fuel pump (20) to the fuel tank (9) is arranged to the return passageway (100, 101) . [0008] Additionally, a second feature is that an upper end of the return passageway (100) is connected to a bottom of the fuel tank (9). [0009] Additionally, a third feature is that a filter member (50) is provided to the supply passageway (200, 201). [0010] Additionally, a forth feature is that a cock (60) for regulating a flow of the fuel is provided to the supply passageway (202, 203) upstream of the filter member (50). [0011] A fifth feature is that the one-way valve (30) includes an umbrella valve (40) having an umbrella portion (42), the umbrella portion (42) covers an end of an opening (37) of a fuel passageway (35a) provided in the one-way valve (30) from the downstream side to prevent passage of fuel from the fuel tank (9) to the fuel pump (20), and on the other hand, when pressured from the fuel pump (20), the umbrella portion (42) deforms to permit communication through the return passageway (100, 101). [0012] Additionally, a sixth feature is that the umbrella portion (42) is arranged at an angle relative to the vertical direction. [0013] Additionally, a seventh feature is that the filter member (50) includes a filtering medium for filtering fuel discharged from the fuel tank (9), a suction filter (24) for further filtering the fuel after filtration through the filter member (50) to supply the fuel to an electrical pump (23), the suction filter (24) being made of a nonwoven fabric, is provided in the fuel pump (20), and coarseness of the filtering medium of the filter member (50) is greater than that of the nonwoven fabric of the suction filter (24). [0014] Additionally, an eighth feature is that coarseness of the filtering medium of the filter member (50) is generally 10 pm, and coarseness of the nonwoven fabric of the suction filter (24) is generally 70 pm. [0015] Additionally, a ninth feature is that the filter member (50) is structured to contain the filtering medium (55) in a case including a body portion (52) and a lid member (51) attached to and covering an opening of the body portion (52). [0016] Further, a tenth feature is that the supply passageway (200, 201) includes an upper supply passageway (200) coupled to the lid member (51) of the filter member (50) and a lower supply passageway (201) connected to the body portion (52) of the filter member (50), and the other end of the lower supply passageway (201) is in communication with a casing (22) of the fuel pump (20). [Advantageous Effect of Invention] [0017] According to a first feature, since a one-way valve for permitting only passage from a fuel pump to a fuel tank is arranged to a return passageway, fuel in the return passageway can be prevented from flowing back from the fuel tank to the fuel pump. Accordingly, it is unnecessary to extend an open end of the return passageway on the fuel tank side to above an oil level of the fuel tank, and for example, the open end can be connected to a bottom of the fuel tank. Therefore, a structure of the fuel tank can be simplified, and production processes of the fuel tank can be reduced. [0018] According to a second feature, since an upper end of the return passageway is connected to the bottom of the fuel tank, a structure of the fuel tank is simplified and an overall length of the return passageway can be shortened in comparison with a structure in which the return passageway projects into the fuel tank, and the production processes can be further reduced. [0019] According to a third feature, since a filter member is provided to a supply passageway, the filter member for filtering all the fuel supplied to the fuel pump can be attached easily in comparison with a case in which the filter member is provided, e.g., in the fuel tank. Additionally, in comparison with a case in which the filter member is provided, e.g., in the fuel tank, its attachment and detachment are easy, and further, even when the filter member is clogged to increase a passage resistance, a back flow of fuel from the return passageway can be prevented. [0020] According to a forth feature, since a cock for regulating a flow rate of fuel is provided to the supply-passageway upstream of the filter member, the filter member can be detached from the supply passageway without spilling fuel in the fuel tank by closing the cock. Additionally, by driving an engine in a state in which the cock has been closed, fuel in the filter member and fuel pump can be removed easily. [0021] According to a fifth feature, a one-way valve includes an umbrella valve having an umbrella portion, the umbrella portion covers open ends of the fuel passageway provided in the one-way valve from the downstream side to prevent passage of fuel from the fuel tank to the fuel pump, and on the other hand, when pressured from the fuel pump, the umbrella portion deforms to permit communication through the return passageway, the one-way valve can be structured using a single component. [0022] According to a sixth feature, since the umbrella portion is arranged at an angle relative to the vertical direction, bubbles gather to a part of the umbrella portion, and can pass more smoothly. [0023] According to a seventh feature, the filter member includes a filtering medium for filtering fuel discharged from the fuel tank, a suction filter made of a nonwoven fabric to further filter the fuel after filtration by the filter member to provide the fuel to the electric pump is provided in the fuel pump, and since coarseness of the filtering medium of the filter member is greater than coarseness of the nonwoven fabric of the suction filter, even fine impurities etc. are absorbed by the filter member on the supply passageway to reduce clogging of the suction filter in the fuel pump, and thus a replacement period of the suction filter can be prolonged. Additionally, since replacement of the filter member on the supply passageway is easy in comparison with that of the suction filter in the fuel pump, maintainability can be improved significantly. [0024] According to a ninth feature, since coarseness of the filtering medium of the filter member is generally 10 pm and coarseness of the nonwoven fabric of the suction filter is generally 70 yim, a replacement interval of the suction filter in the fuel pump can be longer while even fine impurities etc. are adsorbed by the filter member on the supply passageway. [0025] According to a ninth feature, since the filter member is structured to contain the filtering medium in a case including a body portion and a lid member attached to and covering an opening of the body portion, the filtering medium in the filter member can be replaced easily by removing the lid from the body portion. Accordingly, the filtering medium Is replaceable without removing the filter member from the vehicle body, and maintainability can be improved. [0026] According to a tenth feature, since the supply passageway includes an upper supply passageway connected to the lid member of the filter member and a lower supply passageway connected to the body portion of the filter member, and the other end of the lower supply passageway is in communication with the casing of the fuel pump, a piping structure after passage through the filter member is simplified, and impurities can be prevented from entering the casing of the fuel pump. [Brief Description of Drawings] [0027] [Fig. 1] Fig. 1 is a side view of a motorcycle to which a fuel supply device of one embodiment of the present invention is applied. [Fig. 2] Fig. 2 is a block diagram showing a structure of the fuel supply device of one embodiment of the present invention. [Fig. 3] Fig. 3 is a sectional view of a fuel pump. [Fig. 4] Fig. 4 is a side view of a one-way valve unit. [Fig. 5] Fig. 5 is a sectional view of the one-way valve unit. [Fig. 6] Fig. 6 is a top view of a one-way valve. [Fig. 7] Fig. 7 is a partial sectional side view of a pre-filter. [Fig. 8] Fig. 8 is a perspective view of a filtering medium contained in the pre-filter. [Fig. 9] Fig. 9 is a view for explaining an arrangement of the fuel pump seen from a right side of a vehicle body. [Fig. 10] Fig. 10 is a view for explaining an arrangement of the fuel pump seen from a front of the vehicle body. [Fig. 11] Fig. 11 is a schematic view for explaining an operating state of the fuel supply device when fuel in the fuel tank has been run out. [Fig. 12] Fig. 12 is a schematic view showing a structure of the fuel supply device of a second embodiment of the present invention. [Fig. 13] Fig. 13 is a schematic diagram showing a structure of a modification of the fuel supply device. [Description of Embodiments] [0028] Hereafter, in reference to drawings, preferred embodiments of the present invention will be explained in detail. Fig. 1 is a side view of a motorcycle 1 to which a fuel supply device of one embodiment of the present invention is applied. A head pipe 7 rotatably journaling a steering stem not shown is joined to a front end of a vehicle body frame 6. A pair of left and right front forks 2 is coupled to the steering stem. A front wheel WF rotatably journaled to lower ends of the front forks 2 is steerable by a steering handlebar 4 fixed to upper portions of the front forks 2. Additionally, a front fender 3 is attached above the front wheel WF, and a headlight 5 is arranged ahead of the head pipe 7. [0029] A V-type two-cylinder engine 7 as a driving source of the motorcycle 1 is supported by the vehicle body frame 6. A fuel injector 19 is provided between the front and back cylinders, and an air cleaner box 8 is attached to its right side relative to the vehicle body. Two mufflers 18 are attached to exhaust ports respectively formed to a front portion of the front cylinder and to a rear portion of the back cylinder. [0030] A pivot plate not shown is coupled to a rear end of the vehicle body frame 6. A swing arm 11 rotatably journaling a rear wheel WR as a driving wheel is pivotally journaled by a pivot shaft provided to the pivot plate, and a rear side of the arm is suspended by a pair of left and right rear cushion units 12 from a rear portion of the vehicle body frame 6. Additionally, a rear fender 14 to which a taillight device 15 is provided is attached above the rear wheel WR, and a seat 13 is arranged ahead of the rear fender. [0031] A fuel tank 9 to which a cap 10 of a filler opening is attached is arranged above the engine 7. A recess extending in a vehicle body longitudinal direction is attached to a lower surface of the fuel tank 9 to straddle the vehicle body frame 6 extending in the vehicle body-longitudinal direction from its above. A pair of left and right side covers 16 is attached to a lower portion of the seat 13. An out-tank type fuel pump 20 is arranged inside the side covers 16. The fuel pump 20 is a device for pumping fuel supplied from the fuel tank 9 to the fuel injector 19 and its an injector 70 (see Fig. 2) at a predetermined pressure, and in this embodiment, arranged below the lowermost portion of the fuel tank 9. Hereinafter, the entire device including at least the fuel tank 9, the fuel pump 20, and multiple pipes for coupling these components is called "fuel supply device." [0032] Fig. 2 is a schematic view showing a structure of the fuel supply device of one embodiment of the present invention. Reference signs similar to the above ones represent similar or equivalent portions. A supply side opening 9a, which is an outlet of fuel toward the fuel pump 20, and a return side opening 9b, which is a return opening (entry) of fuel from the fuel pump 20, are provided to the bottom surface of the fuel tank 9. A "supply passageway" for supplying fuel to the fuel pump 20 is attached to the supply side opening 9a. The "supply passageway" of this embodiment includes an upper supply passageway 200 and a lower supply passageway 201, between which a pre-filter 50 as a filter member for filtering fuel is arranged. [0033] Fuel supplied to the fuel pump 20 enters a casing 22 forming a storage space of fuel after all the fuel is filtered by the pre-filter 50. When a filter member having a similar function is provided inside the fuel tank 9, a new piping structure is needed in the fuel tank 9, but according to the above structure, the fuel supply device having the pre-filter 50, which is replaceable, outside the fuel tank 9 can be obtained by arranging the filter between the upper supply passageway 200 and the lower supply passageway 201. [0034] An electrical pump 23 for discharging fuel in the casing 22 from a discharge passageway 300 at the same time as fuel introduction through a suction filter 24 is provided in the fuel pump 20. The other end of the discharge passageway 300 is coupled to the injector 70 of the fuel injector 19 (see Fig. 1). A pressure regulator 28 for maintaining a pressure of fuel at a predetermined value is provided to the discharge passageway 300, and excess fuel generated in association with pressure regulation is discharged into the casing 22. [0035] A "return passageway" for returning bubbles generated in the fuel pump 20 to the fuel tank 9 is attached to the return side opening 9b of the fuel tank 9. The "return passageway" of this embodiment includes an upper return passageway 100 and a lower return passageway 101, between which a one-way valve unit 30 permitting only passage from the fuel pump 2 0 to the fuel tank 9 is arranged. [0036] Fuel in the casing 22 and fuel discharged from the pressure regulator 28 contain bubbles 150 including vapor gas mainly generated by evaporation of fuel. An inner structure for introducing all the bubbles 150 existing in the casing 2 2 and moving upward by buoyancy to the lower return passageway 101 is provided to the fuel pump 20. [0037] In this embodiment, a feature is that, by providing the one-way valve unit 30 in the middle of the return passageway which couples the fuel tank 9 and casing 22, a backflow of fuel from the fuel tank 9 to the fuel pump 20 is prevented while permitting upward passage of the bubbles 150. Accordingly, the open end of the upper return passageway 100 can be provided below an oil level of fuel in the fuel tank 9, in other words, to a position where the open end sinks in fuel. In this embodiment, a structure is that a pipe etc. does not project into the fuel tanJc 9 by coupling the open end of the upper return passageway 100 directly to the return side opening 9b. [0038] It is noted that the bubbles 150 are not restricted to ones contained in excess fuel discharged from the pressure regulator 28. For example, a vapor-liquid separator mechanism may be provided to the electrical pump 23 for the direct discharge from the electrical pump 23 into the casing 22 so that the air babbles 150 are not contained in the excess fuel discharged from the pressure regulator 28. [0039] Fig. 3 is a sectional view of the fuel pump 20. Reference signs similar to the above ones represent similar or equivalent portions. The fuel pump 20 is structured such that an opening of the casing 22 having a blind cylindrical shape is sealed by a lid member 21. The lid member 21 includes: an introduction opening 25 coupled to the lower supply passageway 201 (see Fig. 2) and in communication with a space in the casing 22; an outlet 29 coupled to the lower return passageway 101; a discharge opening 27 coupled to the discharge passageway 300; and a connector 45 for supplying electricity to the electrical pump 23. Bubbles generated in association with driving of the electrical pump 23 pass by their buoyancy from a passageway (not shown) formed near a receptacle for a pump opening 26 and the pressure regulator 2 8 through an upper space in communication with the outlet 29, and discharged from the outlet 29. [0040] The electric pump 23 having a cylindrical shape is fitted to a lower surface of the lid member 21, and the suction filter 24 for filtering fuel is attached to a lower end of the electric pump 23. When driving the electric pump 23, fuel is introduced through the suction filter 24 and delivered from a pump opening 26, and the delivered fuel is discharged from the discharge opening 27 in communication with the pump opening 26. In this embodiment, the suction filter 24 is multi-layered, and its coarseness is set to generally 70 lam (60 to 80 pm) . It is noted that, although the suction filter 24 of this embodiment is such that a filter member having the generally same size in the illustrated vertical direction as the fuel pump 23 is arranged in the illustrated vertical direction, various modifications are possible in, e.g., a shape and attachment position of the suction filter 24, and for example, the suction filter 24 may be arranged to a lower portion of the fuel pump 23 in the illustrated horizontal direction. [0041] Additionally, the pressure regulator 28 for maintaining a pressure of fuel at a predetermined value is arranged to the discharge opening 2 7 of the lid member 21, and excess fuel in association with pressure regulation is returned to a space in the casing 22. The outlet 29 connected to the lower return passageway 101 is in communication with the space in the casing 22, and the bubbles 150 are discharged upward from this outlet 29. In such a structure of the fuel supply device as described above, the inside of the casing 22 and each fuel passageway are all filled with fuel during usual operation of the fuel pump 2 0. [0042] Fig. 4 is a side view of the one-way valve unit 30. Additionally, Fig. 5 is a sectional view of the unit, and Fig. 6 is a top view of a one-way valve contained in the one-way valve unit 30. The one-way valve unit 30 is structured to contain the one-way valve in a case 31 formed of, e.g., a resin and having a generally cylindrical shape. An outlet pipe 34 engaged with the upper return passageway 100 is formed to an upper portion (illustrated on the right side) of the case 31, and on the other hand, an introduction pipe 3 5 engaged with the lower return passageway 101 is formed to a lower portion (illustrated on the left side) of the case 31. [0043] In reference to Fig. 5, an umbrella valve 40 as a one-way valve is arranged in an inner space of the case 31. The umbrella valve 40 includes an umbrella portion 42 having a disk shape whose thickness decreases outward in the radial direction and a support portion 41 standing on a central position in the radial direction of this umbrella portion 42. In the case 31, a wall portion standing inward in the radial direction is provided to shield a passageway. The umbrella valve 40 is supported at a generally radial center of fuel passageways 34a, 35a by inserting the support portion 41 into a through hole formed to this wall portion. Additionally, multiple openings 37 are formed to the wall portion. [0044] The umbrella portion 42 has a diameter capable of completely covering the multiple openings 37 in communication with the fuel passageway 3 5a. The multiple openings 37 are formed at an even pitch on a circle inside the umbrella portion 42, the circle being around the support portion 40 of the umbrella valve 40, the support portion 41 being concentric with the fuel passageway 35a of the introduction pipe 35. Accordingly, even when the one¬way valve unit 3 0 is attached to the vehicle body in a state in which its passage direction (central axis direction of the support portion 41) is inclined relative to the vertical direction, at least one of the openings 37 can be arranged higher in the vertical direction. Accordingly, the bubbles 150 can be discharged more smoothly from the opening 37. [0045] Additionally, the umbrella valve 40 closes the openings 3 7 from a downstream side (illustrated on the right side) to prevent fuel from flowing back from the discharge pipe 34 (fuel tank 9) . On the other hand, when the bubbles 150 move upward from the introduction pipe 35 (fuel pump 20), reach the back surface of the umbrella portion 42, and gather to have a certain size, a circumferential portion of the umbrella portion 42 deforms to be everted by their buoyancy in order to pass the bubbles 150. Thus, the umbrella portion 42 can deform only by the buoyancy of the bubbles 150 to pass the bubbles 150. [0046] Fig. 7 is a partial sectional side view of the pre-fliter 50. Additionally, Fig. 8 shows a perspective view of a filtering medium (filter paper) 55 contained in the pre-filter 50. The pre-filter 50 is structured such that the filtering medium (filter paper) 55 is contained in a case including a body portion 52 formed of, e.g., a resin and having a generally cylindrical shape and a lid member 51 attached to and covering an opening of the body portion 52. The lid member 51 and the body portion 52 are detachable because they are coupled by screwing and using an engagement member, and the filtering medium (filter paper) 55 is replaceable alone easily without removing the pre-filter 50 from the vehicle body. [0047] It is noted that the lid member 51 and the body portion 52 may be also welded by a spin weld etc. In this case, the filtering medium (filter paper) 55 is replaced by replacing the pre-fliter 50. [0048] An introduction pipe 54 engaged with the upper supply passageway 200 is formed to the illustrated right side (upstream side) of the lid member 51, and on the other hand, a discharge pipe 53 engaged with the lower supply passageway 201 is formed to the illustrated left side (downstream side) of the body portion 52, The upper supply passageway 200 and lower supply passageway 201 are formed of a resin such as a rubber, and fixed to the introduction pipe 54 and discharge pipe 53 by using a clip 56 after engaged with these pipes, respectively. The other end of the lower supply passageway 201 is connected to the introduction opening 2 5 formed to the lid member 21 of the fuel pump 20, and in communication with the casing 22 (see Fig. 3) . [0049] The filtering medium (filter paper) 55 of the pre-filter 50 has a blind cylindrical shape which is open toward the lid member 51, and is contained in the body portion 52 and covered by the lid member 51 to surround the inlet of fuel. In this embodiment, coarseness of the filtering medium (filter paper) 55 of the pre-filter 50 is set to generally 10 ym (5 to 20ym). On the other hand, coarseness of the nonwoven fabric of the suction filter 24 (see Fig. 3) in the fuel pump 20 is set great, generally 70ym. Therefore, a particle diameter of impurities passing through the suction filter 24 is set coarser than a particle diameter of impurities passing through the pre-filter 50. According to this structure, even fine impurities etc. are absorbed through the pre-filter 50 on the supply passageway, so that clogging of the suction filter 24 is prevented to prolong a replacement interval of the suction filter 24. As described above, since the replacement of the pre-filter 50 is easy in comparison with the replacement of the suction filter 24 in the fuel pump 20, maintainability is improved significantly. [0050] Fig. 9 is a diagram for explaining an arrangement of the fuel pump 20 seen from the right side of the vehicle body. Additionally, Fig. 10 is a diagram for explaining an arrangement of the fuel pump 2 0 seen from the front of the vehicle body. Reference signs similar to the above ones represent similar or equivalent portions. The fuel pump 20 is arranged to a space inside the pair of left and right side covers 16 and rightward of the vehicle body. A battery 17 is arranged leftward of the fuel pump 20 relative to the vehicle body. The fuel pump 20 is arranged behind and below the fuel tank 9 relative to the vehicle body, and accordingly, the supply passageway and return passageway also are arranged at a rearward and downward angle. The supply passageway and return passageway are formed of a flexible tube made of rubber etc., respectively, and arranged between the pair of right and left vehicle body frames 6. [0051] The fuel tank 9 is formed of a metal such as a steel plate. Pipe members are welded outside the supply side opening 9a and the return side opening 9b to be engaged with the upper supply passageway 200 and the upper return passageway 100, respectively. In this embodiment, the supply side opening 9a and the return side opening 9b are made apart from one another in the longitudinal direction of the vehicle body, and the return side opening 9b is provided higher, to prevent the bubbles 150 returned to the fuel tank 9 from being drawn into the supply side opening 9a again. It is noted that the supply side opening 9a and the return side opening 9b may be provided apart from one another in the width direction of the vehicle body, [0052] The pre-filter 50 is arranged inside the side covers 16 fixed to the vehicle body frame with a screw etc., and thus easily replaced. The fuel pump 20 needs to be disassembled to clean or replace the suction filter 24 in the fuel pump 20, but according to the fuel supply device of this embodiment, because of the provision of the pre-filter 50, a maintenance interval for the suction filter 24 can be extended significantly. [0053] The one-way valve unit 30 is arranged at a predetermined forward angle relative to the vertical direction in response to inclination of the upper return passageway 100 and the lower return passageway 101. When, at this time, the openings 37 (see Fig. 5) in the one-way valve unit 30 are arranged to an upper side of the vehicle body, the bubbles 150 can pass upward more smoothly. Additionally, as well as the pre-filter 50, the one-way valve unit 30 also is attached and detached to and from the vehicle body easily. [0054] Fig. 11 is a schematic view for explaining an operating state of the fuel supply device when fuel in the fuel tank 9 has been run out. Reference signs similar to the above ones represent similar or equivalent portions. When operation of the engine 7 continues in a state in which the fuel tank 9 is empty, an oil level in the fuel pump 20 falls gradually. Also in this case, because of the provision of the one-way valve unit 30, fuel in the upper return passageway 100, in other wards, fuel not filtered by the pre-filter 50 is prevented from being introduced into the fuel pump 20. It is noted that a confirmation window for viewing a remaining amount of fuel in the fuel pump 20 may be provided to, e.g., a side surface of the casing 22. [0055] Additionally, when dirt is accumulated in the pre-filter 50 to increase a filtration resistance, a phenomenon in which the oil level in the fuel pump 20 falls may occur although fuel exists in the fuel tank 9. Also in this case, because of the provision of the one-way valve unit 30, fuel not filtered by the pre-filter 50 is not introduced into the fuel pump 20. [0056] Fig. 12 is a schematic view of the fuel supply device of a second embodiment of the present invention. Reference signs similar to the above ones represent similar or equivalent portions. In this embodiment, a cock 60 for freely regulating a flow rate is provided to the supply passageway upstream of the pre-filter 50. It is noted that the cock 6 0 may be switched by two steps, ON and OFF. The cock 60 is provided between a first supply passageway 202 and a second supply passageway 2 03, and when the engine 7 continues to operate in a state in which the cock 60 is off, fuel can be removed from the pre-filter 50 and the fuel pump 20. Accordingly, these components, from which fuel has been removed, can be detached. [0057] It is noted that flow rate detecting means including, e.g., mechanical and ultrasonic flow rate sensors can be provided in the middle of the supply passageway. Accordingly, abnormality of, e.g., the fuel pump and pipes can be detected according to a change of a flow rate per a unit time, and a predetermined interval such as a replacement time of the pre-filter 50 can be detected according to cumulative values of the flow rate. [0058] Fig. 13 is a schematic diagram showing a structure of a modification of the fuel supply device. The fuel supply device can be also structured without providing the one-way valve unit 30 in the middle of the return passageway. In this modification, an upper end of the return passageway 102 is directly connected to a bottom of the fuel tank 9, and therefore, a return passageway 103 in the tank is provided extending to above an oil level A when the tank is full of fuel. Also with this structure, bubbles can be returned from the out-tank type fuel pump to the fuel tank. [0059] As described above, according to the fuel supply device of the present invention, since the one-way valve unit including the umbrella valve is provided in the middle of the return passageway for returning bubbles from the out-tank type fuel pump to the fuel tank, the bubbles can be returned to the fuel tank through the return passageway, and a back flow through the return passageway can be prevented. Additionally, since the pre-filter is provided to the supply passageway, the filter member filtering the entire fuel supplied to the fuel pump can be easily 1 attached. [0060] It is noted that structures and arrangements of the fuel pump, one-way valve unit, and fuel tank, arrangements and shapes of the supply side opening and return side opening of the fuel tank, shapes and materials of the umbrella valve, piping layouts of the supply passageway and return passageway, etc., are not limited to the above embodiments, and various modifications are possible. For example, the fuel supply device may be structured to only provide the one-way valve unit to the return passageway without providing the pre-filter to the supply passageway. The fuel supply device of the present invention is not restricted to a motorcycle, and can be applied to various vehicles such as a three-wheeled vehicle and a four-wheeled vehicle. [Reference Signs List] [0061] 1...Motorcycle 9...Fuel tank 9a...Supply side opening 9b...Return side opening 16 . ..Side cover 19...Fuel injector 20...Fuel pump 22...Casing 23...Electrical pump 24...Suction filter 28 ... Pressure regulator 30...One-way valve unit 37...Opening 40...Umbrella valve 41...Support portion 42...Umbrella portion 50 ...Pre-fliter (Filter member) 60...Cock 100...Upper return passageway 101...Lower return passageway 150...Bubble 200...Upper supply passageway 201...Lower supply passageway 300 ... Discharge passageway [Document Name] Claims [Claim 1] A fuel supply device in which fuel in a fuel tank (9) is supplied to a fuel pump (20) arranged below the fuel tank (9) through supply passageways (200, 201), fuel is supplied to a fuel injector (19, 70) by driving the fuel pump (20), and a bubble (150) generated in the fuel pump (20) is returned to the fuel tank (9) through a return passageway (100, 101), wherein a one-way valve (30) for permitting only passage from the fuel pump (20) to the fuel tank (9) is arranged to the return passageway (100, 101). [Claim 2] The fuel supply device according to claim 1 wherein an upper end of the return passageway (100) is connected to a bottom of the fuel tank (9). [Claim 3] The fuel supply device according to claim 1 or 2 wherein a filter member (50) is provided to the supply passageway (200, 201). [Claim 4] The fuel supply device according to claim 3 wherein a cock (60) for regulating a flow of fuel is provided to the supply passageway (202, 203) upstream of the filter member (50) . [Claim 5] The fuel supply device according to any one of claims 1 to 4 wherein the one-way valve (30) includes an umbrella valve (40) having an umbrella portion (42), the umbrella portion (42) covers an end of an opening (37) of a fuel passageway (35a) provided in the one-way valve (3 0) from a downstream side to prevent passage of fuel from the fuel tank (9) to the fuel pump (20), and meanwhile, when pressured from the fuel pump (20), the umbrella portion (42) deforms to permit communication through the return passageway (100, 101). [Claim 6] The fuel supply device according to claim 5 wherein the umbrella portion (42) is arranged at an angle relative to a vertical direction. [Claim 7] The fuel supply device according to claim 3, wherein: the filter member (50) includes a filtering medium for filtering fuel discharged from the fuel tank (9) ; a suction filter (24) formed of a nonwoven fabric to further filter fuel after filtration by the filter member (50) and to supply the fuel to an electric pump (23) is provided; and coarseness of the filtering medium of the filtering member (50) is greater than coarseness of the nonwoven fabric of the suction filter (24). [Claim 8] The fuel supply device according to claim 7, wherein: the coarseness of the filtering medium of the filter member (50) is generally 10 pm; and the coarseness of the nonwoven fabric of the suction filter (24) is generally 70 ym. [Claim 9] The fuel supply device according to claim 3 wherein the filter member (50) contains the filtering medium (55) in a case including a body portion (52) and a lid member (51) attached to and covering an opening of the body portion (52) . [Claim 10] The fuel supply device according to claim 9, wherein: the supply passageway (200, 201) includes an upper supply passageway (200) connected to the lid member (51) of the filter member (50) and a lower supply passageway (201) connected to the body portion (52) of the filter member (50); and an other end of the lower supply passageway (201) is in communication with a casing (22) of the fuel pump (20). |
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| Patent Number | 271739 | ||||||||||||||||||
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| Indian Patent Application Number | 215/CHE/2010 | ||||||||||||||||||
| PG Journal Number | 10/2016 | ||||||||||||||||||
| Publication Date | 04-Mar-2016 | ||||||||||||||||||
| Grant Date | 02-Mar-2016 | ||||||||||||||||||
| Date of Filing | 28-Jan-2010 | ||||||||||||||||||
| Name of Patentee | HONDA MOTOR CO., LTD. | ||||||||||||||||||
| Applicant Address | 1-1, MINAMI-AOYAMA 2-CHOME, MINATO-KU, 107-8556 | ||||||||||||||||||
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| PCT International Classification Number | F02M 37/00 | ||||||||||||||||||
| PCT International Application Number | N/A | ||||||||||||||||||
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