Title of Invention

FUEL SUPPLY SYSTEM OF A MOTORCYCLE

Abstract In a motorcycle fuel supply system in which a fuel tank 20 is mounted on a main pipe 6a (a vehicle body frame) which extends in a longitudinal direction of a motorcycle, a tunnel-like recessed portion through which the main pipe 6a passes is formed at a laterally central portion of a lower tank (a bottom wall portion) 22 of the fuel tank 20 and a fuel pump 26 for supplying fuel to an engine is disposed within the fuel tank 20, the fuel pump 2 6 is disposed on a bottom central portion 22b in such a manner that an axis L of the fuel pump 2 6 is directed in the longitudinal direction of the motorcycle, and a fuel filter 27 is disposed at a bottom side portion 22c which is stepped down.
Full Text Description MOTORCYCLE FUEL SUPPLY SYSTEM
Technical Field
The present invention relates to a fuel supply system, in which a fuel pump is disposed in a saddle-type fuel tank, is mounted on a vehicle body frame of a motorcycle.
Background Art
In motorcycles in recent years, there exists a case where a fuel supply system is provided in which fuel pressurized by a fuel pump is injected for supply to an engine via fuel injection valve. In this case, while it is considered that the fuel pump is disposed outside the fuel tank, when this construction is adopted, the airtightness around a regulator which is provided as an auxiliary to the fuel pump needs to be ensured, and piping becomes necessary for returning fuel at high pressure from the regulator to the fuel tank. It is difficult, however, to ensure spaces where these components are disposed. Then, conventionally, the fuel pump is attempted to be disposed within the fuel tank (refer to JP-A-2002-293281).
Incidentally, in a case where the fuel pump is
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disposed in the interior of a fuel tank, depending on where the fuel tank is disposed, there may be caused a problem that the tank height and the tank width become large, and hence the fuel tank has to be enlarged in size. For example, as described in the aforesaid Japanese unexamined patent publication, in the event that a construction is adopted in which the fuel tank is disposed at a central portion of a bottom wall of the saddle-type fuel tank in such a manner as to be erected therefrom, there is caused a concern that the tank height is increased. The invention was made in view of the above situations, and an object thereof is to provide a motorcycle fuel supply system which can prevent the enlargement of the fuel tank when the fuel pump is disposed in the interior of the fuel tank-Disclosure of the Invention
According to a first aspect of the invention, there is provided a motorcycle fuel supply system in which a fuel tank is mounted on a vehicle body frame which extends in a longitudinal direction of a motorcycle, a tunnel-like recessed portion through which the vehicle body frame passes is formed at a laterally central portion of a bottom wall portion of the fuel tank and a fuel pump for supplying fuel to an engine is disposed within the fuel tank, the
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motorcycle fuel supply systembeing characterized in that the fuel pump is disposed on the bottom wall portion in such a manner that an axis of the fuel pump is directed in the longitudinal direction of the motorcycle.
According to a second aspect of the invention, there is provided a motorcycle fuel supply system as set forth in the first aspect of the invention, characterized in that the fuel pump is disposed at a bottom central portion which forms the recessed portion in the bottom wall portion of the fuel tank, in that a fuel filter having an inlet port is disposed at a bottom side portion which is stepped down from the recessed portion in the bottom wall portion on a side of the recessed portion, and in that the inlet port of the fuel filter and a suction port of the fuel pump are connected to each other by a fuel piping.
According to a third aspect of the invention, there is provided a motorcycle fuel supply system as set forth in the second aspect of the invention, characterized in that the fuel piping is laid out on an outside of the fuel tank.
According to a fourth aspect of the invention, there is provided a motorcycle fuel supply system as set forth in the second aspect of the invention, characterized in that the fuel piping is laid out within the fuel tank.
According to a fifth aspect of the invention, there
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is provided a motorcycle fuel supply system as set forth in the fourth aspect of the invention, characterized in that the fuel piping is made of a material having a rigidity, in that the fuel piping is pulled out of the interior of the tank so as to be connected to the fuel filter, and in that, in this state, the fuel filter is mounted on the bottom wall portion from the outside of the tank.
According to a sixth aspect of the invention, there is provided a motorcycle fuel supply system as set forth in the fourth aspect of the invention, characterized in that the fuel piping is made of a material having a rigidity which is supported by the fuel pump, and in that the fuel filter is suspended and supported by the fuel piping.
According to a seventh aspect of the invention, there is provided a motorcycle fuel supply system in which a fuel tank is mounted on a vehicle body frame which extends in longitudinal direction of a motorcycle, a tunnel-like recessed portion through which the vehicle body frame passes is formed at a laterally central portion of a bottom wall portion of the fuel tank and a fuel pump for supplying fuel to an engine is disposed within the fuel tank, the motorcycle fuel supply system being characterized in that the fuel pump is disposed at a bottom side portion which is stepped down from the recessed portion in the bottom wall portion on a side of the recessed portion with an
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axis of the fuel pump being directed in a vertical direction of the motorcycle.
According to an eighth aspect of the invention, there is provided a motorcycle fuel supply system as set forth in the seventh aspect of the invention, characterized in that the fuel filter is integrally connected to a suction port of the fuel pump.
According to a ninth aspect of the invention, there is provided a motorcycle fuel supply system as set forth in any of the second to sixth and eighth aspects of the invention, characterized in that a fluid level sensor is disposed at an inlet port portion of the fuel filter, whereby a fuel residual volume warning is displayed when a detection value from the fluid level sensor is entered.
According to a tenth aspect of the invention, there is provided a motorcycle fuel supply system as set forth in the ninth aspect of the invention, characterized in that a fuel reservoir chamber for reserving a small volume of fuel is independently provided at the inlet port portion of the fuel filter, and in that the fluid level sensor is disposed within the fuel reservoir chamber.
According to an eleventh aspect of the invention, there is provided a motorcycle fuel supply system in which a fuel tank is mounted on a vehicle body frame which extends in a longitudinal direction of a motorcycle and a fuel
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pump for supplying fuel to an engine is disposed within the fuel tank, the motorcycle fuel supply system being characterized in that a bottom central portion situated laterally centrally and a bottom side portion situated laterally sideways and vertically downward of the bottom central portion are formed on a bottom wall portion of the fuel tank, in that an opening is formed in the bottom side portion, the opening being closed by a plate member which is detachable and in that the fuel pump is disposed on a side of the plate member which constitutes an internal side of the tank in such a manner that an axis of the fuel pump is directed substantially vertically.
According to a twelfth aspect of the invention, there is provided a motorcycle fuel supply system as set forth in the eleventh aspect of the invention, characterized in that the plate member is detachably mounted on a side of the bottom side portion which constitutes an external side of the tank by a mounting member via a seal member which is interposed between the bottom side portion and the plate member, and in that at least part of the mounting member which is situated on a laterally outermost side is disposed at a position where the part of the mounting member substantially overlaps a laterally outermost portion of the seal member when viewed in the longitudinal direction of the motorcycle.
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According to a thirteenth aspect of the invention, there is provided a motorcycle fuel supply system as set forth in the twelfth aspect of the invention, characterized in that the whole of the mounting member which is situated on a laterally outermost side is disposed at a position where the whole of the mounting member substantially overlaps a laterally outermost portion of the seal member when viewed m the longitudinal direction of the motorcycle.
Brief Description of the Drawings
Fig. 1 is a side view of a motorcycle provided with a fuel supply system according to a first embodiment of the invention.
Fig. 2 is a side view of a fuel tank of the fuel supply system.
Fig. 3 is a sectional view of the fuel tank.
Fig. 4 is a schematic sectional view of a fuel pump disposed in the interior of the fuel tank.
Fig. 5 is a schematic view of a fuel filter of the fuel pump.
Fig. 6 is a schematic view of a fuel filter provided with a fuel reservoir chamber according to an embodiment of the invention as set forth in a tenth aspect of the invention.
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Fig. 7 is a schematic view of a fuel filter provided with a fuel reservoir chamber according to another example of the embodiment.
Fig. 8 is a sectional view of a fuel tank according to a first modified example of the first embodiment.
Fig. 9 is a side view of a fuel tank according to a second modified example of the first embodiment.
Fig. 10 is a sectional view of the fuel tank.
Fig. 11 is a sectional view of a fuel tank according to a third modified example of the first embodiment.
Fig. 12 is a side view of a fuel tank according to a second embodiment of the invention as set forth in fourth and fifth aspects of the invention.
Fig. 13 is a sectional view of the fuel tank.
Fig. 14 is a schematic sectional view of a fuel pump unit disposed in the interior of a fuel tank.
Fig. 15 is a schematic side view of a fuel pump unit according to a third embodiment as set forth in a sixth aspect of the invention.
Fig. 16 is a side view of a fuel tank according to a fourth embodiment as set forth in seventh and eighth embodiments of the invention.
Fig. 17 is a sectional view of the fuel tank.
Fig. 18 is a schematic sectional view of a fuel pump unit disposed in the interior of the fuel tank.
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Fig. 19 is a sectional view of a fuel tank provided with a fuel pump unit according to a fifth embodiment as set forth in eleventh to thirteenth aspects of the invention.
Fig. 20 is a plan view of the fuel pump unit.
Fig. 21 is a side view of the fuel pump unit.
Fig. 22 is a bottom view of the fuel pump unit.
Fig. 23 is a plan view showing a modified example of the fuel pump unit.
Fig. 24 is a side view showing a modified example of the fuel pump unit.
Best Mode for Carrying out the Invention
Embodiments of the invention will be described below based on the accompanying drawings.
Figs. 1 to 5 are drawings for describing amotorcycle fuel supply system according to an embodiment (a first embodiment) of the invention, wherein Fig. 1 is a side view of a motorcycle on which a fuel supply system according to the embodiment is mounted, Figs. 2 and 3 are a side view and a sectional view thereof, respectively, Fig.
4 is a schematic sectional view of a fuel pump, and Fig.
5 is a schematic view of a fuel filter.
In the drawings, a reference numeral 1 denotes a motorcycle, and a vehicle body frame 2 thereof includes
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a main frame 6 on which an engine 3 is mounted and on which a front fork 4 and a rear arm 5 are supported, and a seat rail 8 and a seat stay 9 on which a seat 7 is mounted.
The front fork 4 is supported m such a manner as to pivot by a headstock 10 which is secured to a front end of the mam frame 6, and a front wheel 11 is rotatably supported at a lower end of the front fork 4, while a steering handlebar 12 is fixed to an upper end thereof. In addition, the rear arm 5 is supported by a rear end of the main frame 6 in such a manner as to swing vertically, and a rear wheel 13 is rotatably supported at a rear end of the rear arm 5.
The mam frame 6 includes a single mam pipe 6a which extends diagonally downwardly from an upper end portion of the headstock 10 towards the rear of the motorcycle, a single down tube 6b which extends substantially linearly from a lower end of the headstock 10 towards the rear of the motorcycle, and a gusset 14 which connects the headstock 10, mam pipe 6a and down tube 6b together. The main pipe 6a has a tank rail portion 6c which extends linearly from the headstock 10 and a rear arm bracket portion 6d which extends downwardly from a rear end of the tank rail portion 6c in a curved fashion, and the rear arm 5 is supported by the rear arm bracket portion 6d in such a manner as to pivot thereon.
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The engine 3 is suspended and supported by the main pipe 6a and the down tube 6b with a crankshaft 3a thereof being oriented in a lateral direction of the motorcycle. In addition, an exhaust manifold 15 is connected to a front wall of a cylinder head 3b of the engine 3 and an intake manifold 16 is connected to a rear wall thereof.
A fuel tank 20 is mounted on the tank rail portion 6c of the mam pipe 6, and the seat 7 is mounted on the seat rail 8 situated on a rear end of the fuel tank 20. A front-side portion 7a of the seat 7 covers a rear end face of the fuel tank 20.
The fuel tank 20 is constructed such that circumferential edge portions of a generally bowl-like upper tank 21 and a plate-like lower tank 22 are joined together by virtue of welding, and a fuel filler port 21a is formed in the upper tank 21, the fuel filler port 21a being closed by a fuel filler cap 23 in such a manner as to be opened and closed.
A recessed portion 22a is formed at a central portion in a lateral direction of the lower tank 22 in such a manner as to recede upwardly, and the tank rail portion 6c of the main pipe 6a passes through the interior of the recessed portion 22a. By this recessed portion 22a, the lower tank 22 is formed into a configuration which has a bottom central portion 22b which constitutes a wide
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flat plane and bottom side portions 22c, 22c which are stepped down from left and right sides of the bottom central portion 22b. In addition, when viewed from the side of the motorcycle, the bottom central portion 22b is inclined linearly downwardly towards the rear of the motorcycle and is inclined shallower than the tank rail portion 6c. By this, a relatively large gap is provided between the bottom central portion 22 and the tank rail portion 6c, and on-board components {not shown) are disposed in this portion. In addition, the left and right bottom side portions 2 2c are made to have substantially the same height.
Then, the fuel supply system according to the embodiment is mounted in the immediate vicinity of an intake port of the intake manifold 16 and includes a fuel injection valve 2 5 for injecting fuel for supply into the interior of the intake manifold 16, a fuel pump unit 26 for supplying fuel at high pressure to the fuel injection valve 25, a fuel filter 27 for filtering fuel in the fuel tank 20 which is sucked into the fuel pump unit 26, and a controller, not shown, for controlling fuel injection volume from the fuel injection valve 25 and injection timing thereof, and to describe in detail, the following construction is adopted.
The fuel pump unit 26 is accommodated and disposed
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in the interior of the fuel tank 20 and is constructed, as shown in Fig. 4, such that a housing 31 is integrally fixed mainly to a mounting flange 30, and a driving motor 32 is incorporated in the interior of the housing 31.
A pump compartment 31a is formed in the housing 31, and a rotor 33 fixed to a rotational shaft 32 of the driving motor 32 is disposed in the pump compartment 31a. A suction passageway 31b is formed to be connected to one side of the pump compartment 31a and a discharge passageway 31c is formed to be connected to the other side of the pump compartment 31b, respectively.
An upstream end of the suction passageway 31b is connected for communication with a suction pipe 34 which is connected to a side of the mounting flange 30 which is situated on the outside of the tank. A fuel piping 40 is connected to the suction pipe 34, and the fuel piping 40 is connected to the fuel filter 27.
A downstream end of the discharge passageway 31c is connected for communication with a discharge pipe 35 which is connected the side of the mounting flange 30 which is situated on the outside the tank. A discharge hose 36 is connected to the discharge pipe 35, and the fuel injection valve 25 is connected to the fuel piping 40. In addition, a pressure regulator 37 for regulating the pressure of fuel to a constant pressure is interposed
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at an intermediate portion along the length of the discharge passageway 31c, and a return passageway 31d for returning excess fuel into the interior of the fuel tank 20 is formed to be connected to the pressure regulator 37 via a check valve 38.
The fuel filter 27 is constructed such that a filter mam body 27a is connected to a mounting flange 41 and an intake pipe 42 which communicates with the filter main body 27 is connected to a side of the mounting flange 41 which is situated on the outside of the tank, and the fuel piping 40 is connected to the intake pipe 42.
In addition, a thermistor 43, which functions as a fluid level sensor, is disposed in the vicinity of the intakepipe 42 of the filter ma in body 27 . This thermistor 43 isnormally submerged in fuel and outputs a fuel residual volume warning signal to the controller by detecting a change in temperature when exposed due to the fluid level of fuel being lowered. Then, the controller indicates the fuel residual volume warning based on the input of the warning signal. For example, a warning lamp is flashed or a warning buzzer is used.
Then, the fuel pump unit 26 is disposed at a rear end portion of the bottom central portion 22b in the fuel tank 20 with an axis L being oriented in a longitudinal direction of the motorcycle or disposed in such a manner
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as tobemade to fall down sideways along the bottom central portion 22b. The fuel filter 27 is disposed in such a manner as to be erected at a longitudinally central portion of the bottom side portion 22c.
A mounting opening 22e, which is smaller than the outer shape of the mounting flange 30, is formed in the bottom central portion 22b at a position which faces the fuel pump unit 26. The fuel pump unit 26 is inserted into the mounting opening 22e from below the tank, and the mounting flange 30 is brought into abutment with an outer edge portion of the opening 22e via a seal member, not shown, whereby in this state, the fuel pump unit 26 is detachably fastened and fixed to the bottom central portion 22b with a plurality of bolts 45.
In addition, amounting opening 2 2 f, which is smaller than the outer shape of the mounting flange 41, is formed in the bottom side portion 22c at a portion which faces the fuel filter 27. The fuel filter 27 is inserted into the mounting opening 22f from below the tank, and the mounting flange 41 is brought into abutment with an outer edge portion of the opening 22f via seal member, not shown, whereby in this state, the fuel filter 27 is detachably fastened and fixed to the bottom side portion 22c with a plurality of bolts 46. Then, the fuel piping 40 is arranged in the recessed portion 22a on the lower outside
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of the lower tank portion 22 in such a manner as to be laid along the recessed portion 22a and is connected to the intake pipe 42 and the discharge pipe 34 from the outside of the tank.
The function and operation of the embodiment will be described.
According to the fuel supply system of the invention, since the fuel pump unit 26 is disposed in such a manner as to fall sideways in the bottom central portion 22b within the fuel tank 20 so that the axis L thereof is oriented in the longitudinal direction of the motorcycle and the fuel filter 27 is disposed at the bottom side portion 22c which is stepped down from the bottom central portion 22b, the fuel pump unit 26 and the fuel filter 27 can be disposed by making effective use of space within the fuel tank 20 without increasing the tank height and tank width, thereby making it possible to prevent the enlargement of the fuel tank 20 in size.
In addition, since the fuel pump unit 26 is disposed at the bottom central portion 22b which constitutes the relatively wide flat plane, the disposition space and mounting seat can easily be ensured, and also from this point of view, the enlargement of the fuel tank 20 can be prevented.
Since the fuel filter 27 is disposed at the bottom
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side portion 22c, a dead volume which would disable the suction of fuel when the fuel pump unit 26 were disposed at a high portion within the tank can be eliminated, thereby making it possible to use the fuel with no waste. In addition, the fuel filter 27 can be removed from the fuel tank 20 without removing the fuel tank 20 from the vehicle body frame, and hence the maintenance work such as replacing filter elements can be facilitated.
In this embodiment, since the fuel piping 40 is laid out outside and below the fuel tank 2 0, the connecting work of the fuel piping 40 can be implemented from the outside of the tank, thus making it possible to increase the workability.
In addition, since the intake pipe 42 of the fuel filter 27 is situated outside the tank, the fuel filter 2 7 can be removed with the fuel piping 40 being kept connected, maintenance and replacement of filters can be facilitated. In addition, all the fuel can be sucked in and hence fuel can be used up without any waste.
In this embodiment, the thermistor 43 is disposed in the vicinity of the intake pipe 42 of the fuel filter 27, so that the fuel residual volume warning is indicated when a detection volume is entered from the thermistor 43, fuel can be used up to such an extent that the tank becomes almost empty, and the rider can be notified that
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the motorcycle will stop soonest due to running out of fuel.
Figs. 6 and 7 are drawings showing disposing constructions of fluid level sensors according to an embodiment as set forth in a tenth aspect of the invention. In the drawings, like reference numerals to those shown in Fig. 5 denote the same or corresponding portions to those shown in Fig. 5.
Fig. 6 shows an example in which a fuel reservoir chamber 50 having a volume of on the order of 50 to lOOcc is provided independently from a fuel tank 20 on a side of a mounting flange 41 which is situated outside the tank, an intake pipe 42 is connected to a bottom portion of the fuel reservoir chamber 50, and a thermistor 43 is disposed on a lower side of the mounting flange 41 which constitutes of a ceiling portion. When the fluid level of fuel stored in the fuel reservoir chamber 5 0 at all times is lowered, the thermistor 4 3 is exposed to detect a change in temperature and outputs a fuel residual volume warning signal.
Fig. 7 shows an example in which as with the above example, a fuel reservoir chamber 50 is independently formed so as to be connected to a side of a mounting flange 41 which constitutes the outside of the tank, and a float switch 51 is provided in the interior of the fuel reservoir
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chamber 50. When the fluid level of fuel in the interior of the fuel reservoir chamber 50 is lowered, the float switch 51 is activated to output a fuel residual volume warning. According to either of the construction examples, not only can fuel be used up to the extent that the fuel tank becomes almost empty, but also the warning of residual fuel volume can be implemented with good accuracy.
Fig. 8 is a drawing showing a first modified example to the aforesaid embodiment. In the drawing, like reference numerals to those in Fig. 3 denote like or corresponding components to those in Fig. 3.
In this first modified example, a fuel pump unit 26 is disposed in a bottom central portion 22b in a fuel tank 20, fuel filters 27, 27 are disposed at left and right bottom side portions 22c, 22c, respectively. Then, fuel pipings 40, 40 are connected fuel intake pipes 42 of the respective fuel filters 27, 27, and each fuel piping 40 is connected to communicate with a T-shaped suction pipe 34 of the fuel pump unit 26.
According to the first modified example, since the fuel filters 27, 27 are disposed at the left and right bottom side portions 22c, respectively, and each fuel filter 27 is connected to the fuel pump unit 26 via the fuel piping 40, fuel at the left and right bottom side
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portions 22c can be sucked up by the fuel pump unit 26, thereby making it possible to use up fuel in a more ensured fashion.
In addition, the maintenance work of the fuel filters 27 can be facilitated.
Figs. 9 and 10 are drawings which show a second modified example to the aforesaid embodiment. In the drawings, like reference numerals to those in Figs. 2 and 3 denote the same or corresponding components to those shown in Figs. 2 and 3.
The second modified example is an example in which a fuel pump unit 26 is disposed in a bottom central portion 22b of a fuel tank 20, an intake pipe 42 is connected to a bottom side portion 22c from the outside of the tank, and a fuel filter 56 is connected to an outside of the intake pipe 42 via a closing valve 55 interposed therebetween.
In the closing valve 55, a fuel inlet passageway 55a which communicates with the intake pipe 42 and an outlet passageway 55b which communicates with a fuel piping 40 are formed, and closing valves 55c, 55d are disposed in the respective passageways 55a, 55b. A common valve stem 55e is fixed to each of the passageways 55a, 55b, and a stopcock 55f is attached to the valve stem 55e.
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When the stopcock 55f is rotated manually to an open position, fuel in the fuel tank 2 0 flows into the fuel filter 56 through the inlet passageway 55a for filtration, further flows from the fuel filter 56 through the outlet passageway 55b and is sucked into the fuel pump unit 26 via the fuel piping 40. When the stopcock 55f is rotated to a close position, the inlet passageway 5 5a and the outlet passageway 55b are closed at the same time, whereby the fuel filter 56 can be removed with allowing fuel to remain within the interior of the fuel tank 20, thereby making it possible to facilitate the maintenance and filter replacement.
Fig. 11 shows an example in which, similarly to the aforesaid example, a fuel filter 27 is disposed at an opposite bottom side wall to the bottom side wall 22c where the fuel filter 56 is disposed, and the fuel filter 27 is connected to a fuel pump unit 26 via a fuel piping 40. In this example, fuel filter elements 56 can be replaced with fuel allowing to remain in the fuel tank 20 and fuel can be used up in an ensured fashion.
Fig. 12 to 14 are drawings which describe a fuel supply system according to another embodiment (a second embodiment) as set forth in fourth and fifth aspects of the invention. In the drawings, like reference numerals to those in Figs. 2 to 4 denote like or corresponding
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components to those in Figs. 2 to 4.
In this embodiment, a fuel pump unit 26 is disposed at a bottom central portion 22b in a fuel tank 20, a fuel filter 27 is disposed at a bottom side portion 22b, the fuel filter 27 and the fuel pump unit 26 are connected to each other by a flexible fuel piping 60, and the fuel piping 60 is laid out in the interior of the fuel tank 20 .
The fuel piping 60 is such as to be laid out in the following procedure. The fuel piping 60 is connected to an intake pipe 34 of the fuel pump unit 26 in advance, and the fuel pump unit 26 is inserted into the interior of the tank from a mounting opening 22e together with the fuel pump unit 26 and is then mounted on a bottom central 22b. Next, the fuel piping 60 is pulled out from a mounting opening 22f in a bottom side 22c and is connected to an intake pipe 42. In this state, the fuel filter 27 is inserted from the mounting opening 22f to be mounted on the bottom side portion 2 2c.
In this embodiment, since the fuel piping 60 is laid out in the interior of the fuel tank 20, no piping is necessary to be laid out outside the tank, thereby making it possible to improve the appearance.
In addition, since the fuel piping 60 is made to be flexible, the fuel piping 60 is connected to the pump
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fuel unit 26 in advance, the fuel piping 60 is pulled out to the outside of the tank to be connected to the fuel filter 2 7, and in this state, the fuel filter 27 is mounted on the bottom wall portion 22c, the laying out work of the fuel piping 60 within the tank can be facilitated.
Fig. 15 is a drawing which describes a fuel supply system according to an embodiment (a third embodiment) as set forth in a sixth aspect of the invention. In the drawing, like reference numerals to those in Fig. 14 denote like or corresponding components to those m Fig. 14.
In this embodiment, a rigid metallic fuel piping 63 is constructed to be supported by a fuel pump unit 26, and a fuel filter 64 is constructed to be suspended and supported by the fuel piping 63.
The fuel piping 63 is connected to communicate with a suction passageway 31b of a housing 31 of the fuel pump unit 26 and is fixed to the housing 31 with a fixture 65. In addition, the fuel filter 64 is fixedly connected to an upstream port of the fuel piping 63 and is disposed at a position in the vicinity of a bottom side of a bottom side portion 22c.
In this embodiment, since the rigid fuel piping 63 is fixedly connected to the fuel pump unit 26 and the fuel filter 64 is suspended and supported by the fuel
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piping 63, the fuel piping 63 and the fuel filter 64 can be assembled to the fuel pump 26 in advance so as to be formed into an assembly, thereby making it possible to facilitate the assembly of the fuel pump unit 26.
Figs. 16 to 18 are drawings which describe a fuel supply system according to an embodiment (a fourth embodiment) as set forth in seventh and eighth aspects of the invention. In the drawings, like reference numerals to those in Figs. 2 to 4 denote like or corresponding components to those in Figs. 2 to 4.
In this embodiment, a fuel pump unit 70 is disposed in a fuel tank 20 at a longitudinally central portion of a bottom side portion 22c and is erected so that an axis L of the fuel pump unit 7 0 becomes substantially normal in a vertical direction of the motorcycle.
A fuel filter 71 is integrally formed to be connected to a housing 31 of the fuel pump unit 70. In addition, a suction passageway 31b is opened in a lower end portion of the housing 31, and an inlet port 71a of the fuel filter 71 is connected to communicate with the suction passageway 31b. The inlet port 71a of the fuel filter 71 is formed at a position in the vicinity of a bottom side of the bottom side portion 22c.
In this embodiment, since the fuel pump unit 70 is disposed in such a manner that the axis L of the fuel
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pump unit 70 is directed substantially normally in the vertical direction of the motorcycle, the fuel pump unit 70 can be disposed at a location where a maximum margin can be provided as to the height dimension of the fuel tank 20, and the fuel pump unit 70 can be disposed to be accommodated within the fuel tank 2 0 without increasing the tank height and tank width, thereby making it possible to prevent the enlargement of the fuel tank 20 in size.
In addition, the fuel pump unit 70 can be removed from the fuel tank 20 with the fuel tank 20 being kept attached to the vehicle frame, thereby making it possible to facilitate the maintenance work of the fuel pump unit 70.
In addition, since the fuel filter 71 is integrally connected to the fuel pump unit 70, the necessity of a fuel piping which connects both the fuel pump unit and the fuel filter together can be obviated, and furthermore, the inlet port 71a of the fuel filter 71 can be positioned in the bottom side of the bottom side portion 22c, thereby making it possible to use up fuel by eliminating the dead volume of fuel.
Figs. 19 to 22 are drawings which describe a fuel supply system according to an embodiment {a fifth embodiment) as set forth in eleventh to thirteenth aspects of the invention.
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In the fifth embodiment, a fuel tank 20 is supported by the tank rail portion 6 of the vehicle body frame which extends in the longitudinal direction of the motorcycle. This fuel tank 20 is constructed by joining together a circumferential edge portion 21a of an upper tank (an outer wall portion) 21 and a circumferential edge portion 22g of a lower tank (a bottom wall portion) 22 by virtue of welding, and the basic configuration thereof is similar to those of the respective embodiments that have been described heretofore.
The lower tank (bottom wall portion) 22 of the fuel tank 20 includes a bottom central portion 22b which is situated laterally centrally and bottom side portions 22c, 22c which are situated laterally outwardly and vertically downwardly of the bottom central portion 22b. In other words, the bottom central portion 22b constitutes a recessed portion which is made to recede inwardly of the tank and the bottom side portion 2 2c is stepped downward from the bottom central portion 22b.
An opening 22h is formed in the bottom side portion 22c. The opening 22h is formed into an elliptic shape and is disposed such that a major axis thereof is directed m the longitudinal direction of the motorcycle, and consequently, a minor axis thereof is directed in the transverse direction thereof. In addition, the opening
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22h is detachably closed by a plate member 30 which covers the opening 22h and which is formed into a rectangular shape. A fuel pump unit 70 is provided on a side of the plate member 30 which constitutes an interior side of the tank. This fuel pump unit 70 includes a fuel pump 70a which is fixedly disposed on the side of the plate member 30 which constitutes the interior side of the tank m such a manner that the axis L thereof extends along substantially the vertical direction and a feeding connector 70b and a discharge pipe 70 which are disposed on a side of the plate member 30 which constitutes an exterior side of the tank. An oil filter 70d is incorporated m a bottom portion of the fuel pump 70a which is fixed to the plate member 30. In addition, the feeding connector 70b is connected to a motor of the fuel pump 70a via a feeding wiring harness 70b', and the discharge pipe 70c is connected to communicate with a discharge port of the fuel pump 70a via a discharge hose 70c' . In addition, the fuel pump 70a, the connector 70br the wiring harness 70b', the discharge pipe 70c, and the discharge hose 70c' are arranged in line in such a manner as to extend in the longitudinal direction of the motorcycle or along the major axis of the elliptic shape. The plate member 30 is detachably mounted with, for example, four sets of bolts and nuts (mounting members)
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73a, 73b by inserting the fuel pump unit 70 into the interior of the tank from the opening 22h and bringing the plate member 30 into abutment with the side of the bottom side portion 22c which constitutes the exterior side of the tank with a seal member 72 being interposed between the bottom side portion 22c of the lower tank 22 and itself.
Here, the seal member 72 is formed into an elliptic shape which is slightly large in diameter than the elliptic opening 22h and which surrounds the periphery of the fuel pump unit 70, has linear portions {laterally outermost portions) 72a, 72a which are parallel with the major axis of the elliptic shape and arc portions 7 2b, 7 2b which connect the linear portions with each other and is disposed m such a manner that the linear portions 72a are directed in the longitudinal direction of the motorcycle. Then, the four sets of bolts and nuts 73a, 73b are disposed at positions where as viewed in the longitudinal direction of the motorcycle (in a direction indicated by an arrow B) , center lines of the bolts overlap the linear portions 72a, 72a of the seal member 72. Note that the bolt 73a is disposed in such a manner as to penetrate the tank wall from the inside to the outside of the tank, and a bolt head thereof is welded to the bottom side portion 22c fluid-tightly. In addition, 3 0a denotes an insertion
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hole for the bolt 73a.
In the embodiment constructed as has been described above, since the fuel pump unit 7 0 is disposed within the bottom side portion 22c which is positioned below the bottom central portion 22b of the lower tank 22, the fuel pump 70 can be constructed so as to be elongated in the direction of the axis L as required, thereby making it possible to ensure a large pump capacity.
In addition, since the plate member 30 on which the fuel pump unit 70 is mounted is constructed so as to be detachably mounted from the outside of the tank, the attaching and detaching work of the fuel pump unit 70 can be facilitated, thereby making it possible to improve the maintenance properties.
Furthermore, in making the plate member 30 detachable, since the bolts 73a and nuts 73b are disposed in such a manner as to overlap the linear portions 72a of the seal member 72, the plate member 30 and hence the lateral dimension of the fuel pump unit 7 0 can be suppressed to a minimum dimension, and even in the event that the widthwise dimension of the bottom side portion 22c of the fuel tank 20 is narrow, the pump unit can be disposed. Note that in the embodiment, while the all the bolts 73a are disposed in such a manner as to overlap the seal member, only either of the left and right bolts can be
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disposed in such a manner as to overlap the seal member.
Furthermore, as to the arrangement of the bolts 73a, as shown in Fig. 23, a bolt 73a' can be added at an intermediate position between the front and rear bolts 73a, 73a, and by adopting the construction, the sealing properties can further be increased.
In addition, while the fifth embodiment has been described as the oil filter 70d being incorporated in the bottom portion of the fuel pump 70a, it is, of course, possible to adopt a construction in which an oil filter 70d' may be, as shown in Fig. 24, disposed outwardly of the fuel pump 7 0a.
Industrial Applicability
According to the fuel supply system of the first aspect of the invention, since the fuel pump is disposed on the bottom wall portion within the fuel tank in such a manner that the axis of the fuel pump is directed in the longitudinal direction of the motorcycle, by disposing the fuel pump in such a manner as to fall sideways on, for example, the bottom central portion which constitutes the recessed portion in the bottom wall portion, the bottom side portion or the vertical wall portion between the bottom central portion and the bottom side portion, the fuel pump can be disposed to be accommodated within the
30

fuel tank without increasing the tank height and tank width, thereby making it possible to prevent the enlargement of the fuel tank in size.
According to the second aspect of the invention, since the fuel pump is disposed at the bottom central portion of the bottom wall portion, there can be provided a relatively extra margin in disposition space, and the fuel pump can be disposed at a location where the mounting seat can easily be ensured, thereby making it possible to prevent the enlargement of the fuel tank in size.
In addition, since the fuel filter is disposed at the bottom side portion which is stepped down from the bottom central portion, it is possible to eliminate the dead volume which disables the suction of fuel when the fuel pump is disposed at a higher location on the bottom wall portion, whereby fuel can be used up. In addition, the fuel filter can be removed from the fuel tank without removing the fuel tank fromthe vehiclebody frame, thereby making it possible to facilitate the replacement work of filter elements.
According to the third aspect of the invention, since the fuel piping is laid out on the exterior side of the fuel tank, the connecting work of the fuel piping can be implemented from the outside, thereby making it possible to increase the workability.
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In addition, by positioning the inlet port of the fuel filter in the bottom wall portion, the suction of fuel that is situated higher than the mounting position of the fuel filter can be implemented, thereby making it possible to use up fuel.
According to the fourth aspect of the invention, since the fuel piping is laid out within the fuel tank, no piping is required on the exterior side of the tank, thereby making it possible to improve the external appearance.
According to the fifth aspect of the invention, since the fuel piping is made of the flexible material, the fuel piping is pulled out from the interior of the tank so as to be connected to the fuel filter and in this state, the fuel filter is mounted on the bottom wall portion, the mounting work can be facilitated which is necessary when the fuel piping is laid out within the fuel tank.
According to the sixth aspect of the invention, since the rigid fuel piping is supported by the fuel pump and the fuel filter is suspended and supported by the fuel piping, the fuelpiping and the fuel filter can be assembled to the fuel pump in advance so as to form an assembly, thereby facilitating the assembly of the fuel pump.
According to the seventh aspect of the invention, since the fuel pump is disposed at the bottom side portion
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of the bottom wall portion which is stepped down in such a manner that the axis of the fuel pump is directed vertically, the fuel pump can be disposed at the location where there is provided a maximum margin in the height dimension of the fuel tank, and the fuel pump can be disposed to be accommodated within the fuel tank without increasing the tank height and tank width, thereby making it possible to prevent the enlargement of the fuel tank in size. In addition, the fuel pump can be removed from the fuel tank without removing the fuel tank from the vehicle body frame, thereby making it possible to facilitate the maintenance work of the fuel pump.
According to the eighth aspect of the invention, since the fuel filter is integrally connected to the fuel pump, the necessity of a fuel piping for connecting both the filter and the pump can be obviated, and the inlet port of the fuel filter can be located at a lower position, so that the dead volume of fuel can be eliminated, thereby making it possible to use up fuel.
According to the ninth aspect of the invention, since the fluid level sensor is disposed at the inlet port portion of the fuel filter so that a fuel residual volume warning is indicated when a detection value is entered from the fluid level sensor, fuel can be used to such an extent that there remains almost no fuel in the tank, and the
33

rider can be warned that the motorcycle nearly runs out of fuel to thereby be forced to stop.
According to the tenth aspect of the invention, since the fuel reservoir chamber is independently provided at the inlet port portion of the fuel filter and the fluid level sensor is disposed within in the fuel reservoir chamber, the warning of fuel residual volume can be implemented with good accuracy.
According to the eleventh aspect of the invention, since the fuel pump is disposed at the bottom side portion of the bottom wall portion of the fuel tank which is situated downwardly of the bottom central portion in such a manner that the axis of the fuel pump is directed substantially vertically, the fuel pump can be disposed at the location of the fuel tank where there is provided the maximum margin in the height dimension thereof, whereby the fuel pump can be made to have a required capacity without increasing the tank height and tank width.
In addition, since the fuel pump is disposed on the plate member adapted to detachably close the opening in the bottom side portion, the fuel pump can be removed from the fuel tank without removing the fuel tank from the vehicle body frame, thereby facilitating the maintenance work of the fuel pump.
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According to the twelfth aspect of the invention, since at leastpart of the mounting member which is situated on a laterally outermost side is disposed at a position where the part of the mounting member substantially overlaps a laterally outermost portion of the seal member when viewed in the longitudinal direction of the motorcycle, the lateral dimension of the plate member can be suppressed to a minimum dimension, whereby even in the event that the lateral dimension of the bottom side portion of the fuel tank cannot be ensured sufficiently, the fuel pump can be disposed within the fuel tank.
According to the thirteenth aspect of the invention, since the whole of the mounting member which is situated on a laterally outermost side is disposed at a position where the whole of the mounting member substantially overlaps a laterally outermost portion of the seal member when viewed in the longitudinal direction of the motorcycle, the lateral dimension of the plate member can be made smaller.
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Claims
1. A motorcycle fuel supply system in which a fuel tank is mounted on a vehicle body frame which extends in a longitudinal direction of a motorcycle, a tunnel-like recessed portion through which the vehicle body frame passes is formed at a laterally central portion of a bottom wall portion of the fuel tank and a fuel pump for supplying fuel to an engine is disposed within the fuel tank, the motorcycle fuel supply system being characterized in that the fuel pump is disposed on the bottom wall portion in such a manner that an axis of the fuel pump is directed in the longitudinal direction of the motorcycle. 2 . A motorcycle fuel supply system as set forth in Claim
1, characterized in that the fuel pump is disposed at
a bottom central portion which forms the recessed portion
in the bottom wall portion of the fuel tank, in that a
fuel filter having an inlet port is disposed at a bottom
side portion which is stepped down from the recessed
portion in the bottom wall portion on a side of the recessed
portion, and in that the inlet port of the fuel filter
and a suction port of the fuel pump are connected to each
other by a fuel piping.
3. A motorcycle fuel supply system as set forth in Claim
2, characterized in that the fuel piping is laid out on
an outside of the fuel tank.
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4. A motorcycle fuel supply system as set forth in Claim
2, characterized in that the fuel piping is laid out within
the fuel tank.
5. Amotorcycle fuel supply system as set forth in Claim
4 , characterized m that the fuel piping is made of a
material having a rigidity, in that the fuel piping is
pulled out of the interior of the tank so as to be connected
to the fuel filter, and in that, in this state, the fuel
filter is mounted on the bottom wall portion from the
outside of the tank.
6. Amotorcycle fuel supply system as set forth in Claim
4, characterized in that the fuel piping is made of a
material having a rigidity which is supported by the fuel
pump, and in that the fuel filter is suspended and supported
by the fuel piping.
7 . A motorcycle fuel supply system in which a fuel tank is mounted on a vehicle body frame which extends in a longitudinal direction of a motorcycle, a tunnel-like recessed portion through which the vehicle body frame passes is formed at a laterally central portion of a bottom wall portion of the fuel tank and a fuel pump for supplying fuel to an engine is disposed within the fuel tank, the motorcycle fuel supply system being characterized in that the fuel pump is disposed at a bottom side portion which is stepped down from the recessed portion in the bottom
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wall portion on a side of the recessed portion with an axis ofthe fuel pump being directed ma vertical direction of the motorcycle.
8. A motorcycle fuel supply system as set forth in Claim
7, characterized in that the fuel filter is integrally
connected to a suction port of the fuel pump.
9. A motorcycle fuel supply system as set forth in any
of Claims 2 to 6 and 8, characterized in that a fluid
level sensor is disposed at an inlet port portion of the
fuel filter, whereby a fuel residual volume warning is
displayed when a detection value from the fluid level
sensor is entered.
10 . A motorcycle fuel supply system as set forth in Claim 9, characterized in that a fuel reservoir chamber for reserving a small volume of fuel is independently provided at the inlet port portion of the fuel filter, and in that the fluid level sensor is disposed within the fuel reservoir chamber.
11. A motorcycle fuel supply system in which a fuel tank is mounted on a vehicle body frame which extends in a longitudinal direction of a motorcycle and a fuel pump for supplying fuel to an engine is disposed within the fuel tank, the motorcycle fuel supply system being characterized in that a bottom central portion situated laterally centrally and a bottom side portion situated
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laterally sideways and vertically downward of the bottom central portion are formed on a bottom wall portion of the fuel tank, in that an opening is formed in the bottom side portion, the opening being closed by a plate member which is detachable and in that the fuel pump is disposed on a side of the plate member which constitutes an internal side of the tank in such a manner that an axis of the fuel pump is directed substantially vertically.
12. A motorcycle fuel supply system as set forth in Claim
11, characterized in that the plate member is detachably
mounted on a side of the bottom side portion which
constitutes an external side of the tank by a mounting
member via a seal member which is interposed between the
bottom side portion and the plate member, and in that
at least part of the mounting member which is situated
on a laterally outermost side is disposed at a position
where the part of the mounting member substantially
overlaps a laterally outermost portion of the seal member
when viewed in the longitudinal direction of the
motorcycle.
13. A motorcycle fuel supply system as set forth in Claim
12, characterized in that the whole of the mounting member
which is situated on a laterally outermost side is disposed
at a position where the whole of the mounting member
substantially overlaps a laterally outermost portion of
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the seal member when viewed in the longitudinal direction of the motorcycle.





40
In a motorcycle fuel supply system in which a fuel tank 20 is mounted on a main pipe 6a (a vehicle body frame) which extends in a longitudinal direction of a motorcycle, a tunnel-like recessed portion through which the main pipe 6a passes is formed at a laterally central portion of a lower tank (a bottom wall portion) 22 of the fuel tank 20 and a fuel pump 26 for supplying fuel to an engine is disposed within the fuel tank 20, the fuel pump 2 6 is disposed on a bottom central portion 22b in such a manner that an axis L of the fuel pump 2 6 is directed in the longitudinal direction of the motorcycle, and a fuel filter 27 is disposed at a bottom side portion 22c which is stepped down.

Documents:


Patent Number 246735
Indian Patent Application Number 326/KOLNP/2005
PG Journal Number 11/2011
Publication Date 18-Mar-2011
Grant Date 14-Mar-2011
Date of Filing 03-Mar-2005
Name of Patentee YAMAHA HATSUDOKI KABUSHIKI KAISHA
Applicant Address 2500 SHINGAI,IWATA-SHI,SHIZUOKA-KEN 438-8501
Inventors:
# Inventor's Name Inventor's Address
1 KAZUSHIGE TAIRA C/O-YAMAHA HATSUDOKI KABUSHIKI KAISHA 2500 SHINGAI,IWATA-SHI,SHIZUOKA-KEN 438-8501
2 MITSUGU SUZUKI C/O-YAMAHA HATSUDOKI KABUSHIKI KAISHA 2500 SHINGAI,IWATA-SHI,SHIZUOKA-KEN 438-8501
PCT International Classification Number F02M 37/00
PCT International Application Number PCT/JP2004/001747
PCT International Filing date 2004-02-17
PCT Conventions:
# PCT Application Number Date of Convention Priority Country
1 2003-037905 2003-02-17 Japan