Saddle-type multi-characteristic fuel vehicle

Abstract

The purpose of the present invention is to provide a saddle-type multi-characteristic fuel vehicle which has a vehicle size smaller than that of a general automobile having a cabin, for which the space for disposing component parts is restricted, and which has a small fuel tank, wherein a filter for multi-characteristic fuel can be disposed and supported in addition to a tank for multi-characteristic fuel, and a mixing state of received fuel and existing fuel after refueling can be dealt with by a mechanical design. In the present invention, because both a primary low-pressure filter and a secondary low-pressure filter constituting a low-pressure filter assembly are provided to a fuel pump or a mounting member, the low-pressure filter assembly can be compactly supported in a vehicle body of a saddle-type multi-characteristic fuel vehicle together with a fuel tank for the saddle-type multi-characteristic fuel vehicle, and a positional relationship between a start point and an end point of a low-pressure free flow path portion of a filtered fuel circulation flow path can be mechanically and structurally determined.

Description

Saddle-type multi-property fuel vehicle

[0001] The present invention relates to a straddle-type multi-characteristic fuel vehicle, and more particularly to a straddle-type multi-characteristic fuel vehicle equipped with an internal combustion engine capable of burning a plurality of types of fuels with different characteristics.

[0002] Saddle-type multi-characteristic fuel vehicles have been known in the past. Saddle-type multi-characteristic fuel vehicles have an internal combustion engine capable of burning multiple types of fuel with different characteristics. Examples of such saddle-type multi-characteristic fuel vehicles are disclosed in the following patent documents:

[0003] Patent Document 1 discloses a fuel pump unit that minimizes the impact of changes in fuel composition on fuel injection control, is compact, and easy to install. Specifically, the fuel pump unit includes a case, a partition wall, an intake port, and a fuel pump. The case includes a discharge port through which fuel is discharged and a return port through which excess fuel returns. The partition wall divides the interior space of the case into a return fuel chamber and a main fuel chamber. The return fuel chamber is provided with a return port. The main fuel chamber is connected to the outside of the case. The intake port is located within the return fuel chamber. The fuel pump draws fuel through the intake port and discharges it through the outlet port. Patent Document 2 discloses the provision of a sub-tank that functions as a fuel storage section separated from the fuel tank. This allows the two fuels to be mixed gently, even when a fuel with a different fuel composition is refueled. Patent Document 3 discloses a fuel filter structure that extends the filter's life and allows the filter to be compactly housed within the case. Specifically, a primary filter is provided upstream of the fuel pump, and a secondary filter made of a nonwoven fabric with a finer mesh than the primary filter is provided downstream of the fuel pump. By making the mesh of the primary filter coarser, the life of the primary filter can be extended, thereby also extending the life of the fuel pump provided downstream of the primary filter. A secondary filter made of nonwoven fabric has high filtration efficiency, is compact, and has a longer life since the primary filter shares the filtration load. Patent Document 4 discloses a motorcycle that can improve the ease of removing a fuel tank. Specifically, a fuel pump unit is attached to the underside of the fuel tank. The fuel pump unit supplies fuel from the fuel tank to the engine. The filter is located downstream of the fuel pump unit in the fuel supply path from the fuel tank to the engine. The filter is attached to the fuel tank. A pressure regulator is located downstream of the filter in the fuel supply path from the fuel tank to the engine. The pressure regulator is attached to the fuel tank.

[0004] JP 2014-51894 A JP 2008-280031 A JP 2008-248751 A JP 2014-113835 A

[0005] A straddle-type vehicle is smaller in size than a typical automobile having a cabin. This limits the space available for arranging components. In such a straddle-type vehicle, a filter for the multi-property fuel must be disposed and supported in addition to a tank for the multi-property fuel. Furthermore, a straddle-type vehicle has a smaller fuel tank than a typical automobile having a cabin. In such a straddle-type vehicle, a mechanical design must address the degree of mixing of the incoming fuel newly supplied to the fuel tank during refueling with the existing fuel remaining in the fuel tank, i.e., the change in fuel properties that occurs during refueling.

[0006] The object of the present invention is to provide a saddle-type multi-property fuel vehicle that is smaller in size than a typical automobile with a cabin, has limited space for arranging components, and has a small fuel tank, and that can arrange and support a filter for multi-property fuel in addition to a tank for multi-property fuel, and that can handle the mixing of the incoming fuel and the existing fuel after refueling through mechanical design.

[0007] The inventors have studied ways to achieve the above object, and have found that the primary and secondary low-pressure filters constituting the low-pressure filter assembly need not have a pressure retention structure and can be inserted into the fuel tank for a saddle-type multi-characteristic fuel vehicle through a mounting hole together with the pressure regulator and fuel pump, so as to determine the relative positions of the start and end points of the low-pressure free flow passage portion in the filtered fuel circulation flow passage for adjusting the degree of mixing of the multi-characteristic fuel in the fuel tank for a saddle-type multi-characteristic fuel vehicle. The present invention was completed based on this finding.

[0008] (1) A saddle-type multi-characteristic fuel vehicle according to one embodiment of the present invention comprises: an internal combustion engine capable of burning a plurality of types of fuel having different characteristics; a saddle-type multi-characteristic fuel vehicle fuel tank configured to store fuel to be supplied to the internal combustion engine, the fuel tank having a filler port for receiving fuel from the outside and a mounting hole, and supported on a body of the saddle-type multi-characteristic fuel vehicle; and an injector configured to supply fuel to the internal combustion engine. Furthermore, within the saddle-type multi-characteristic fuel vehicle fuel tank, a fuel pump configured to draw fuel from within the saddle-type multi-characteristic fuel vehicle fuel tank and pressurize the fuel toward the injector; and a primary low-pressure filter provided to cover the suction port of the fuel pump. a pressure regulator that is provided in a fuel flow path from the fuel pump to the injector, and that passes fuel pressurized by the fuel pump toward the injector while returning low-pressure surplus fuel into the saddle-type multi-characteristic fuel vehicle fuel tank without having a return pipe outside the saddle-type multi-characteristic fuel vehicle fuel tank; and a secondary low-pressure filter that is provided downstream of the low-pressure side of the pressure regulator, and a mounting member that is attached to the saddle-type multi-characteristic fuel vehicle fuel tank so as to cover at least a portion of the mounting hole, thereby positioning the fuel pump within the saddle-type multi-characteristic fuel vehicle fuel tank, wherein the primary low-pressure filter and the secondary low-pressure filter do not have a pressure retention structure and form a low-pressure filter assembly that enters the saddle-type multi-characteristic fuel vehicle fuel tank through the mounting hole together with the pressure regulator and the fuel pump, and The fuel pump or the mounting member is provided with a filter so that the positional relationship between the clean side of the secondary low-pressure filter as the starting point of a low-pressure free flow path portion for adjusting the degree of mixing of fuel in the fuel tank for a saddle-type multi-characteristic fuel vehicle in the filtered fuel circulation flow path and the dirty side of the primary low-pressure filter as the end point can be determined.

[0009] Saddle-type vehicles are driven with the occupant straddling the seat. Therefore, saddle-type vehicles are smaller in size than typical automobiles with cabins. Saddle-type vehicles are required to be maneuverable, lightweight, and easy to use. Therefore, miniaturization of the external dimensions is an important factor for saddle-type vehicles. In the saddle-type multi-characteristic fuel vehicle (1), both the primary and secondary low-pressure filters constituting the low-pressure filter assembly are provided on the fuel pump or mounting member. This allows the low-pressure filter assembly, together with the fuel tank for the saddle-type multi-characteristic fuel vehicle, to be compactly supported on the vehicle body of the saddle-type multi-characteristic fuel vehicle, and also allows the mechanical and structural positional relationship between the start and end points of the low-pressure free flow path portion of the filtered fuel circulation flow path to be determined. More specifically, the fuel tank for the saddle-type multi-characteristic fuel vehicle is used as a support structure for the low-pressure filter assembly on the vehicle body. Both the primary and secondary low-pressure filters constituting the low-pressure filter assembly are disposed within the fuel tank for the saddle-type multi-characteristic fuel vehicle. By supporting the saddle-type multi-characteristic fuel vehicle fuel tank on the vehicle body, not only the saddle-type multi-characteristic fuel vehicle fuel tank but also the low-pressure filter assembly can be supported on the vehicle body. Clamps or the like for supporting the primary and secondary low-pressure filters that make up the low-pressure filter assembly are not required. Therefore, the low-pressure filter assembly can be compactly supported on the vehicle body of the saddle-type multi-characteristic fuel vehicle fuel tank together with the saddle-type multi-characteristic fuel vehicle fuel tank. Furthermore, the primary and secondary low-pressure filters that make up the low-pressure filter assembly are positioned within the saddle-type multi-characteristic fuel vehicle fuel tank with a fixed positional relationship between the clean side of the secondary low-pressure filter and the dirty side of the primary low-pressure filter. Therefore, the positional relationship between the start and end points of the low-pressure free flow path portion of the filtered fuel circulation flow path can be mechanically and structurally determined. Here, the flow rate in the low-pressure portion of the filtered fuel circulation flow path is slower than that in the high-pressure portion through which fuel pressurized by the fuel pump flows. Therefore, in the saddle-type multi-characteristic fuel vehicle (1), a low-pressure free flow passage is provided in the fuel tank for the saddle-type multi-characteristic fuel vehicle, and the positional relationship between the start and end points of the passage is mechanically and structurally determined, making it easier to adjust the degree of fuel mixing.More specifically, a low-pressure free flow path portion that adjusts the degree of fuel mixing is provided by utilizing the space within the fuel tank for a saddle-type multi-characteristic fuel vehicle. This increases the degree of freedom in designing the low-pressure free flow path portion. As a result, the degree of freedom in designing the degree of fuel mixing is increased. Therefore, in a saddle-type vehicle that is smaller in size than a typical automobile with a cabin, it is possible to support the fuel tank for a saddle-type multi-characteristic fuel vehicle and the low-pressure filter assembly while accommodating the degree of mixing of fuels with different characteristics through mechanical and structural design.

[0010] A saddle-type multi-characteristic fuel vehicle is a saddle-type vehicle equipped with an internal combustion engine capable of burning multiple types of fuel with different characteristics. An example of a saddle-type vehicle is a vehicle equipped with a saddle-type seat. An example of a saddle-type vehicle is a vehicle in which a rider sits astride a saddle. Examples of saddle-type vehicles include scooters, mopeds, snowmobiles, personal watercraft, and all-terrain vehicles (ATVs). A saddle-type vehicle includes, for example, at least one front wheel and at least one rear wheel. That is, a saddle-type vehicle is not limited to a two-wheeled vehicle, but may be a tricycle having a pair of front or rear wheels, or a four-wheeled vehicle having a pair of front and rear wheels, respectively. A saddle-type vehicle may be, for example, a tilting vehicle. A tilting vehicle is a vehicle equipped with a body that tilts leftward when turning left and tilts rightward when turning right. "Fuels with different characteristics" includes not only different fuel compositions but also different impurities contained in the fuels. "Fuels with different impurities" includes, for example, different amounts or types of impurities contained in the fuels. The number of combustion chambers in an internal combustion engine is not particularly limited. The number and arrangement of cylinders in an internal combustion engine are not particularly limited. "Capable of burning multiple types of fuels with different characteristics" means, for example, that the combustion system does not switch for each fuel. The fuel filler opening is provided, for example, on the top surface of the saddle-type multi-characteristic fuel vehicle fuel tank. The mounting hole is provided, for example, on the bottom, side, or top surface of the saddle-type multi-characteristic fuel vehicle fuel tank. The vehicle body supporting the saddle-type multi-characteristic fuel vehicle fuel tank includes, for example, a vehicle frame. The injector may supply fuel directly to the combustion chambers of the internal combustion engine or to an intake passage connected to the internal combustion engine. The mounting member may be one or more. If there are multiple mounting members, the fuel pump is provided, for example, on at least one of the mounting members. The fuel pump draws fuel that has passed through a primary low-pressure filter. The fuel pump includes, for example, a motor, an impeller, and a case that houses these. The case has, for example, a divided structure.The height direction of the fuel pump is, for example, the direction in which the rotor shaft of the motor included in the fuel pump extends. When the fuel pump is located in a fuel tank for a saddle-type multi-characteristic fuel vehicle, the direction in which the rotor shaft of the motor included in the fuel pump extends is not particularly limited. Each of the primary low-pressure filter and the secondary low-pressure filter includes, for example, a filter medium for filtering the fuel and a support member for supporting the filter medium. The filter medium may be made of any material, provided that it has the function of filtering the fuel. The support member, for example, has the function of maintaining the filter medium in a predetermined shape. The primary low-pressure filter, for example, passes fuel supplied to the fuel pump while blocking at least some of the impurities contained in the fuel. The secondary low-pressure filter, for example, passes low-pressure excess fuel returned from a pressure regulator to the fuel tank for a saddle-type multi-characteristic fuel vehicle while blocking at least some of the impurities contained in the fuel. The pressure regulator may be disposed in the saddle-type multi-characteristic fuel vehicle fuel tank together with the primary low-pressure filter and the secondary low-pressure filter that constitute the low-pressure filter assembly. The pressure regulator may be provided, for example, on the fuel pump or a mounting member. The pressure regulator may be disposed, for example, at least partially within a fuel pump case. The pressure regulator may have, for example, an outlet port that returns low-pressure excess fuel into the saddle-type multi-characteristic fuel vehicle fuel tank. The secondary low-pressure filter may be connected, for example, to the outlet port. The outlet port may be provided, for example, on the pressure regulator itself. Alternatively, the outlet port may be provided on a pipe or a flow path forming member connected to the pressure regulator. If the pressure regulator is located in the saddle-type multi-characteristic fuel vehicle fuel tank, the pressure regulator may have a return pipe within the saddle-type multi-characteristic fuel vehicle fuel tank. The pressure regulator need not have a return pipe outside the saddle-type multi-characteristic fuel vehicle fuel tank. The fuel flow path from the fuel pump to the injector includes, for example, a flow path formed within a fuel pump case. The pressure maintaining structure is, for example, a structure for maintaining the pressure of the fuel passing through the filter."The primary low-pressure filter and the secondary low-pressure filter do not have a pressure retention structure" includes, for example, cases in which the shape of each of the primary low-pressure filter and the secondary low-pressure filter is not maintained by members other than the members that constitute the filter. For example, the case in which each of the primary low-pressure filter and the secondary low-pressure filter is arranged in an exposed state (e.g., not covered by a case member, etc.) is included in "the primary low-pressure filter and the secondary low-pressure filter do not have a pressure retention structure." For example, the case in which the primary low-pressure filter and the secondary low-pressure filter are arranged inside a fuel pump case is not included in "the primary low-pressure filter and the secondary low-pressure filter do not have a pressure retention structure" because the case corresponds to the pressure retention structure. "The primary low-pressure filter and the secondary low-pressure filter do not have a pressure retention structure" includes, for example, cases in which the dirty side of each of the primary low-pressure filter and the secondary low-pressure filter is exposed to the low-pressure free flow path portion. For example, if the primary low-pressure filter and the secondary low-pressure filter each have a dirty side in at least one direction in the thickness direction, the fact that at least one dirty side is exposed to the low-pressure free flow path portion is included in the statement that "the primary low-pressure filter and the secondary low-pressure filter do not have a pressure-retaining structure." For example, if the filter has a thick plate-like outer shape, the filter has a thickness direction. "The primary low-pressure filter and the secondary low-pressure filter, together with the pressure regulator and the fuel pump, constitute a low-pressure filter assembly that enters the fuel tank for a saddle-type multi-characteristic fuel vehicle through a mounting hole" means, for example, that the primary low-pressure filter and the secondary low-pressure filter have a relationship that allows them to be handled together with the pressure regulator and the fuel pump so that they can enter the fuel tank for a saddle-type multi-characteristic fuel vehicle through a mounting hole together with the pressure regulator and the fuel pump. The filtered fuel circulation flow path is a flow path through which fuel circulates within a saddle-type multi-characteristic fuel vehicle fuel tank so that fuel filtered by each of the primary low-pressure filter and the secondary low-pressure filter is filtered again by each of the primary low-pressure filter and the secondary low-pressure filter. The low-pressure free flow path portion includes, for example, a space existing between the secondary low-pressure filter and the primary low-pressure filter within a saddle-type multi-characteristic fuel vehicle fuel tank.The low-pressure free flow passage portion adjusts the degree of mixing of fuel in the filtered fuel circulation flow passage in the fuel tank for a saddle-type multi-characteristic fuel vehicle by, for example, mixing fuel discharged into the space from the secondary low-pressure filter with fuel already present in the space. The fuel discharged into the space from the secondary low-pressure filter is filtered at least once by each of the primary low-pressure filter and the secondary low-pressure filter. The primary low-pressure filter and the secondary low-pressure filter may be mounted on a fuel pump or a mounting member such that the clean side of the secondary low-pressure filter, which serves as the starting point of the low-pressure free flow passage, and the dirty side of the primary low-pressure filter, which serves as the end point, are positioned in a predetermined relationship. The phrase "the primary low-pressure filter is mounted on the fuel pump" includes, for example, the primary low-pressure filter being connected to the suction port of the fuel pump. The phrase "the secondary low-pressure filter is mounted on the fuel pump" includes, for example, the secondary low-pressure filter being mounted on a component within the fuel pump case. The component may be, for example, a pressure regulator. For example, a case in which a pressure regulator inside a case is exposed from the case and a secondary low-pressure filter is connected to the pressure regulator is also included in the phrase "a secondary low-pressure filter being provided in a fuel pump." It is sufficient for even a portion of the component inside the case to be inside the case. For example, a case in which the secondary low-pressure filter is provided in a component integral with the component inside the case is also included in the phrase "a secondary low-pressure filter being provided in a fuel pump." The component inside the case is, for example, the pressure regulator. The component integral with the component inside the case is, for example, a pipe or a flow path forming component connected to the pressure regulator. The secondary low-pressure filter is provided, for example, to cover the discharge port of the pressure regulator. The discharge port may be formed in the pressure regulator itself, or may be formed in a pipe or a flow path forming component connected to the pressure regulator. The primary low-pressure filter and the secondary low-pressure filter are provided, for example, in the fuel pump or a mounting member so that one surface of the primary low-pressure filter and one surface of the secondary low-pressure filter face each other but are spaced apart from each other.The primary low-pressure filter and the secondary low-pressure filter are provided on the fuel pump or the mounting member, for example, so that one surface of each of the primary low-pressure filter and the secondary low-pressure filter is arranged non-parallel.

[0011] According to one aspect of the present invention, a saddle-type multi-characteristic fuel vehicle can employ the following configuration: (2) In the saddle-type multi-characteristic fuel vehicle described in (1), the pressure regulator is provided on the fuel pump or the mounting member so that a positional relationship is determined between the pressure regulator, the clean side of the secondary low-pressure filter as the starting point of the low-pressure free flow path portion, and the dirty side of the primary low-pressure filter as the end point.

[0012] According to the saddle-type multi-characteristic fuel vehicle of (2), a saddle-type multi-characteristic fuel vehicle fuel tank is used as a support structure for the pressure regulator to the vehicle body. The pressure regulator is disposed within the saddle-type multi-characteristic fuel vehicle fuel tank. By supporting the saddle-type multi-characteristic fuel vehicle fuel tank on the vehicle body, not only the saddle-type multi-characteristic fuel vehicle fuel tank but also the pressure regulator can be supported on the vehicle body. Clamps or the like for supporting the pressure regulator are not required. Therefore, the pressure regulator can be supported compactly on the body of the saddle-type multi-characteristic fuel vehicle together with the saddle-type multi-characteristic fuel vehicle fuel tank.

[0013] According to one aspect of the present invention, the saddle-type multi-characteristic fuel vehicle can employ the following configuration: (3) In the saddle-type multi-characteristic fuel vehicle according to (1) or (2), the primary low-pressure filter and the secondary low-pressure filter each have a fixed shape and are flexible.

[0014] According to the straddle-type multi-characteristic fuel vehicle of (3), for example, when inserting the fuel pump and pressure regulator into the fuel tank for the straddle-type multi-characteristic fuel vehicle through the mounting holes, the primary low-pressure filter and the secondary low-pressure filter can be made compact by, for example, rolling them. Since the primary low-pressure filter and the secondary low-pressure filter then return to their original shapes inside the fuel tank for the straddle-type multi-characteristic fuel vehicle, the primary low-pressure filter and the secondary low-pressure filter are less subject to restrictions such as the shape of the mounting holes. This increases the design freedom for the start and end points of the low-pressure free flow path portion, which is provided by utilizing the space inside the fuel tank for the straddle-type multi-characteristic fuel vehicle. This increases the design freedom for adjusting the degree of fuel mixing in the low-pressure free flow path portion.

[0015] According to one aspect of the present invention, a saddle-type multi-characteristic fuel vehicle can employ the following configuration: (4) The saddle-type multi-characteristic fuel vehicle according to any one of (1) to (3), wherein the primary low-pressure filter and the secondary low-pressure filter are provided on the fuel pump or the mounting member such that the fuel pump is not present between the primary low-pressure filter and the secondary low-pressure filter in a direction in which the primary low-pressure filter and the secondary low-pressure filter overlap at least partially.

[0016] In the straddle-type multi-characteristic fuel vehicle (4), the primary low-pressure filter and the secondary low-pressure filter can be arranged close to each other, and the degree of fuel mixing in the low-pressure free flow path can be adjusted to facilitate fuel mixing in the low-pressure free flow path.

[0017] "In the direction in which at least a portion of the primary low-pressure filter and the secondary low-pressure filter overlap, there is no fuel pump between the primary low-pressure filter and the secondary low-pressure filter" includes, for example, "In the direction perpendicular to the rotation axis of the motor of the fuel pump, there is at least a portion of the primary low-pressure filter and the secondary low-pressure filter overlap, and there is no fuel pump between the primary low-pressure filter and the secondary low-pressure filter."

[0018] According to one aspect of the present invention, a saddle-type multi-characteristic fuel vehicle can employ the following configuration: (5) The saddle-type multi-characteristic fuel vehicle according to any one of (1) to (3), wherein the primary low-pressure filter and the secondary low-pressure filter are provided on the fuel pump or the mounting member such that at least a portion of the fuel pump is present between the primary low-pressure filter and the secondary low-pressure filter in a direction in which at least a portion of the primary low-pressure filter and the secondary low-pressure filter overlap.

[0019] In the straddle-type multi-characteristic fuel vehicle of (5), the primary low-pressure filter and the secondary low-pressure filter can be arranged apart. The degree of fuel mixing in the low-pressure free flow path can be adjusted so that the fuel is less likely to mix in the low-pressure free flow path.

[0020] "At least a part of the fuel pump is located between the primary low-pressure filter and the secondary low-pressure filter in a direction in which at least a part of the primary low-pressure filter and the secondary low-pressure filter overlap" includes, for example, "at least a part of the primary low-pressure filter and the secondary low-pressure filter overlap in a direction perpendicular to the rotation axis of the motor of the fuel pump, and the fuel pump is located between the primary low-pressure filter and the secondary low-pressure filter in that direction."

[0021] According to one aspect of the present invention, a saddle-type multi-characteristic fuel vehicle can employ the following configuration: (6) The saddle-type multi-characteristic fuel vehicle according to any one of (1) to (5), wherein the primary low-pressure filter and the secondary low-pressure filter are provided on the fuel pump or the mounting member such that the primary low-pressure filter is disposed closer to a bottom surface of the fuel tank for the saddle-type multi-characteristic fuel vehicle than the secondary low-pressure filter.

[0022] According to the straddle-type multi-characteristic fuel vehicle of (6), even when the fuel in the fuel tank for the straddle-type multi-characteristic fuel vehicle is running low, the fuel can be circulated within the fuel tank for the straddle-type multi-characteristic fuel vehicle while mixing the fuel in the low-pressure free flow path portion. Even when the fuel in the fuel tank for the straddle-type multi-characteristic fuel vehicle is running low, the degree of fuel mixing in the low-pressure free flow path portion can be adjusted. This increases the design freedom for adjusting the degree of fuel mixing in the low-pressure free flow path portion.

[0023] The above and other objects, features, aspects, and advantages of the present invention will become more apparent from the following detailed description of embodiments of the present invention taken in conjunction with the accompanying drawings. As used herein, the term "and / or" includes any and all combinations of one or more of the associated listed items. As used herein, the use of the terms "including," "comprising," or "having" and variations thereof specifies the presence of stated features, steps, operations, elements, components, and / or equivalents thereof, but may include one or more of the steps, operations, elements, components, and / or groups thereof. Unless otherwise defined, all terms (including technical and scientific terms) used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs. Terms, such as those defined in commonly used dictionaries, should be interpreted to have a meaning consistent with the meaning in the context of the relevant technology and this disclosure, and should not be interpreted in an idealized or overly formal sense unless explicitly defined herein. It is understood that numerous techniques and processes are disclosed in the description of the present invention. Each of these has distinct advantages, and each can also be used with one or more, or in some cases all, of the other disclosed technologies. Therefore, for the sake of clarity, this description will refrain from unnecessarily repeating all possible combinations of individual steps. Nevertheless, the specification and claims should be read with the understanding that all such combinations are within the scope of the present invention and the claims. In the following description, for purposes of explanation, numerous specific details are set forth to provide a thorough understanding of the present invention. However, it will be apparent to one skilled in the art that the present invention may be practiced without these specific details. The present disclosure is to be considered as an example of the present invention and is not intended to limit the invention to the specific embodiments illustrated in the following drawings or description.

[0024] According to the present invention, a saddle-type multi-characteristic fuel vehicle can be provided, which is smaller in size than a typical automobile with a cabin, has limited space for arranging components, and has a small fuel tank.In addition to a tank for multi-characteristic fuel, a filter for multi-characteristic fuel can be arranged and supported in the saddle-type vehicle, and the mixing condition of the incoming fuel and the existing fuel after refueling can be handled by mechanical design.

[0025] The present invention relates to a saddle-type multi-characteristic fuel vehicle, a saddle-type multi-characteristic fuel vehicle, a fuel pump, a saddle-type multi-characteristic fuel vehicle, a fuel pump arrangement ...

[0026] Hereinafter, a saddle-type multi-characteristic fuel vehicle according to an embodiment of the present invention will be described in detail with reference to the drawings. Note that the embodiment described below is merely an example. The present invention should not be construed as being limited in any way by the embodiment described below.

[0027] A saddle-type multi-characteristic fuel vehicle 10 according to an embodiment of the present invention will be described with reference to Figure 1. The saddle-type multi-characteristic fuel vehicle 10 includes an internal combustion engine 12, a saddle-type multi-characteristic fuel vehicle fuel tank 14, and an injector 16.

[0028] The internal combustion engine 12 is capable of combusting multiple types of fuel with different characteristics. The saddle-type multi-characteristic fuel vehicle fuel tank 14 is configured to store fuel to be supplied to the internal combustion engine 12. The saddle-type multi-characteristic fuel vehicle fuel tank 14 has a filler opening 141 for receiving fuel from the outside and a mounting hole 142. In the example shown in FIG. 1 , the mounting hole 142 is formed in the bottom surface (lower surface) of the saddle-type multi-characteristic fuel vehicle fuel tank 14. The saddle-type multi-characteristic fuel vehicle fuel tank 14 is supported on the vehicle body 15 of the saddle-type multi-characteristic fuel vehicle 10. The injector 16 is configured to supply fuel to the internal combustion engine 12.

[0029] The saddle-type multi-characteristic fuel vehicle 10 further includes a mounting member 26 for mounting a fuel pump 18, a primary low-pressure filter 20, a pressure regulator 22, and a secondary low-pressure filter 24 within the saddle-type multi-characteristic fuel vehicle fuel tank 14. The fuel pump 18 is configured to draw fuel from the saddle-type multi-characteristic fuel vehicle fuel tank 14 and pressurize the fuel toward the injectors 16. The primary low-pressure filter 20 is provided to cover the fuel pump suction port. The pressure regulator 22 is provided in the fuel flow path from the fuel pump 18 to the injectors 16. The pressure regulator 22 passes the fuel pressurized by the fuel pump 18 toward the injectors 16. The pressure regulator 22 does not have a return pipe outside the saddle-type multi-characteristic fuel vehicle fuel tank 14. The pressure regulator 22 is configured to return low-pressure excess fuel into the saddle-type multi-characteristic fuel vehicle fuel tank 14. The secondary low-pressure filter 24 is disposed downstream of the low-pressure side of the pressure regulator 22. The fuel pump 18 is provided on the mounting member 26. The mounting member 26 is attached to the saddle-type multi-characteristic fuel vehicle fuel tank 14 so as to cover at least a portion of the mounting hole 142. In this way, the mounting member 26 positions the fuel pump 18 within the saddle-type multi-characteristic fuel vehicle fuel tank 14.

[0030] The primary low-pressure filter 20 and the secondary low-pressure filter 24 do not have a pressure retention structure and constitute a low-pressure filter assembly 28 that, together with the pressure regulator 22 and the fuel pump 18, enters the saddle-type multi-characteristic fuel vehicle fuel tank 14 through the mounting hole 142. The primary low-pressure filter 20 and the secondary low-pressure filter 24 are mounted on the fuel pump 18 so that the positional relationship between the clean side of the secondary low-pressure filter 24 as the start point of a low-pressure free flow path portion 301 in the filtered fuel circulation flow path 30 and the dirty side of the primary low-pressure filter 20 as the end point is determined. The low-pressure free flow path portion 301 is provided to adjust the degree of mixing of fuel in the saddle-type multi-characteristic fuel vehicle fuel tank 14. In Figure 1, in order to clearly show the low-pressure free flow path portion 301, the low-pressure free flow path portion 301 is shown by a virtual line connecting the clean side of the secondary low-pressure filter 24 as the starting point to the dirty side of the primary low-pressure filter 20 as the end point, but the flow of fuel in the low-pressure free flow path portion 301 is not limited to that shown by the virtual line.

[0031] In the saddle-type multi-characteristic fuel vehicle 10, both the primary low-pressure filter 20 and the secondary low-pressure filter 24 that make up the low-pressure filter assembly 28 are provided on the fuel pump 18, so that the low-pressure filter assembly 28 can be compactly supported on the body 15 of the saddle-type multi-characteristic fuel vehicle 10 together with the fuel tank 14 for the saddle-type multi-characteristic fuel vehicle, and the positional relationship between the start point and end point of the low-pressure free flow path portion 301 in the filtered fuel circulation flow path 30 can be mechanically and structurally determined.

[0032] 1, the pressure regulator 22 may be provided in the fuel pump 18 so that a positional relationship between the pressure regulator 22, the clean side of the secondary low-pressure filter 24 as the starting point of the low-pressure free flow path portion 301, and the dirty side of the primary low-pressure filter 20 as the end point is determined. Each of the primary low-pressure filter 20 and the secondary low-pressure filter 24 may have a fixed shape and be flexible, for example.

[0033] FIG. 2 is a schematic diagram illustrating variations in the arrangement of the fuel pump 18 that may be employed in the saddle-type multi-characteristic fuel vehicle 10. In FIG. 1, the fuel pump 18 is disposed vertically within the fuel tank 14 for the saddle-type multi-characteristic fuel vehicle. However, in FIG. 2A, the fuel pump 18 is disposed horizontally within the fuel tank 14 for the saddle-type multi-characteristic fuel vehicle. In FIG. 2B, a mounting hole 142 is provided in an upper surface 144 of the fuel tank 14 for the saddle-type multi-characteristic fuel vehicle. The fuel pump 18 is disposed vertically within the fuel tank 14 for the saddle-type multi-characteristic fuel vehicle. Here, "the fuel pump 18 is disposed vertically" refers to, for example, the fuel pump 18 being disposed so that the rotational axis of the motor included in the fuel pump 18 extends in the vertical direction of the vehicle. "The fuel pump 18 is disposed horizontally" refers to, for example, the fuel pump 18 being disposed so that the rotational axis of the motor included in the fuel pump 18 extends in a direction perpendicular to the vertical direction of the vehicle. 2A and 2B, the primary low-pressure filter 20 and the secondary low-pressure filter 24 are provided on the fuel pump 18 or the mounting member 26 so that the primary low-pressure filter 20 is positioned closer to the bottom surface 143 of the saddle-type multi-characteristic fuel vehicle fuel tank 14 than the secondary low-pressure filter 24. Note that in order to clearly show the low-pressure free flow path portion 301 in FIG. 2, the low-pressure free flow path portion 301 is shown by a virtual line connecting the clean side of the secondary low-pressure filter 24 as the starting point to the dirty side of the primary low-pressure filter 20 as the end point, but the flow of fuel in the low-pressure free flow path portion 301 is not limited to that shown by the virtual line.

[0034] 3A and 3B are schematic diagrams illustrating variations in the arrangement of the primary low-pressure filter 20 and the secondary low-pressure filter 24 that can be employed in the saddle-type multi-characteristic fuel vehicle 10. Fig. 3A shows an example of an arrangement in which the primary low-pressure filter 20 and the secondary low-pressure filter 24 are spaced apart. In Fig. 3A, the primary low-pressure filter 20 and the secondary low-pressure filter 24 are provided on the fuel pump 18 such that at least a portion of the fuel pump 18 is located between the primary low-pressure filter 20 and the secondary low-pressure filter 24 in a direction in which at least a portion of the primary low-pressure filter 20 and the secondary low-pressure filter 24 overlap. Fig. 3B shows an example of an arrangement in which the primary low-pressure filter 20 and the secondary low-pressure filter 24 are close to each other. In Figure 3B, the primary low-pressure filter 20 and the secondary low-pressure filter 24 are provided on the fuel pump 18 so that at least a portion of the fuel pump 18 is not located between the primary low-pressure filter 20 and the secondary low-pressure filter 24 in the direction in which at least a portion of the primary low-pressure filter 20 and the secondary low-pressure filter 24 overlap. Note that in Figures 3A and 3B, the low-pressure free flow path portion 301 is shown by a virtual line connecting the clean side of the secondary low-pressure filter 24 as the starting point and the dirty side of the primary low-pressure filter 20 as the end point for easy understanding. However, the fuel flow in the low-pressure free flow path portion 301 is not limited to that shown by the virtual line. Figure 3C is a diagram for explaining the positional relationship between the primary low-pressure filter 20 and the secondary low-pressure filter 24 in the arrangement of the fuel pump 18 shown in Figure 1. In (C) of Figure 3, the primary low-pressure filter 20 is arranged in region C4, and the secondary low-pressure filter 24 is arranged in region C6. The region in which the primary low-pressure filter 20 is arranged is not limited to region C4. The primary low-pressure filter 20 may be arranged in one region, or may be arranged across multiple regions. The region in which the secondary low-pressure filter 24 is arranged is not limited to region C6. The secondary low-pressure filter 24 may be arranged in one region, or may be arranged across multiple regions. The primary low-pressure filter 20 and the secondary low-pressure filter 24 may be arranged in the same region, or may be arranged in different regions.The primary low-pressure filter 20 and the secondary low-pressure filter 24 may be disposed at the same height or at different heights. FIG. 3D is a diagram illustrating the positional relationship between the primary low-pressure filter 20 and the secondary low-pressure filter 24 in the arrangement of the fuel pump 18 shown in FIG. 2A. In FIG. 3D, the primary low-pressure filter 20 is disposed across regions D7 and D8, and the secondary low-pressure filter 24 is disposed in region D5. The region in which the primary low-pressure filter 20 is disposed is not limited to regions D7 and D8. The primary low-pressure filter 20 may be disposed in one region or may be disposed across multiple regions. The region in which the secondary low-pressure filter 24 is disposed is not limited to region D5. The secondary low-pressure filter 24 may be disposed in one region or may be disposed across multiple regions. The primary low-pressure filter 20 and the secondary low-pressure filter 24 may be disposed in the same region or may be disposed in different regions. The primary low-pressure filter 20 and the secondary low-pressure filter 24 may be disposed at the same height or at different heights. FIG. 3E is a diagram illustrating the positional relationship between the primary low-pressure filter 20 and the secondary low-pressure filter 24 in the arrangement of the fuel pump 18 shown in FIG. 2B. In FIG. 3E, the primary low-pressure filter 20 is disposed across regions E4 and E5, and the secondary low-pressure filter 24 is disposed in region E6. The region in which the primary low-pressure filter 20 is disposed is not limited to regions E4 and E5. The primary low-pressure filter 20 may be disposed in one region or may be disposed across multiple regions. The region in which the secondary low-pressure filter 24 is disposed is not limited to region E6. The secondary low-pressure filter 24 may be disposed in one region or may be disposed across multiple regions. The primary low-pressure filter 20 and the secondary low-pressure filter 24 may be disposed in the same region or may be disposed in different regions. The primary low-pressure filter 20 and the secondary low-pressure filter 24 may be disposed at the same height or at different heights. The shapes of the primary low-pressure filter 20 and the secondary low-pressure filter 24 are not limited to flat plates. For example, they may be curved to fit the outer surface of the fuel pump 18.

[0035] (Other Embodiments) The embodiments and variations described and / or illustrated in this specification are intended to facilitate understanding of the present disclosure and are not intended to limit the scope of the present disclosure. The above-described embodiments and variations may be modified or improved without departing from the spirit of the present disclosure. This spirit encompasses equivalent elements, modifications, deletions, combinations (e.g., combinations of features across embodiments and variations), improvements, and modifications that would be recognized by a person skilled in the art based on the embodiments disclosed herein. The limitations in the claims should be interpreted broadly based on the terms used in the claims and should not be limited to the embodiments and variations described in the specification or prosecution of this application. Such embodiments and variations should be construed as non-exclusive. For example, in this specification, the terms "preferably" and "good" are non-exclusive and mean "preferably but not limited to" or "good but not limited to."

[0036] REFERENCE SIGNS LIST 10 saddle-type multi-characteristic fuel vehicle 12 internal combustion engine 14 fuel tank for saddle-type multi-characteristic fuel vehicle 141 fuel filler neck 142 mounting hole 15 vehicle body 16 injector 18 fuel pump 20 primary low-pressure filter 22 pressure regulator 24 secondary low-pressure filter 26 mounting member 28 low-pressure filter assembly 30 filtered fuel circulation flow path 301 low-pressure free flow path portion

Claims

1. A saddle-type multi-characteristic fuel vehicle comprising: an internal combustion engine capable of burning a plurality of types of fuel having different characteristics; a saddle-type multi-characteristic fuel vehicle fuel tank configured to store fuel to be supplied to the internal combustion engine, the fuel tank having a filler port for receiving fuel from the outside and a mounting hole, and supported on a body of the saddle-type multi-characteristic fuel vehicle; and an injector configured to supply fuel to the internal combustion engine. Further, the saddle-type multi-characteristic fuel vehicle fuel tank comprises a fuel pump configured to draw fuel from the saddle-type multi-characteristic fuel vehicle fuel tank and to pressurize the fuel toward the injector, and a primary low-pressure filter provided to cover the suction port of the fuel pump. a pressure regulator that is provided in a fuel flow path from the fuel pump to the injector, and that passes fuel pressurized by the fuel pump toward the injector while returning low-pressure surplus fuel into the fuel tank for a saddle-type multi-characteristic fuel vehicle without having a return pipe outside the fuel tank for a saddle-type multi-characteristic fuel vehicle; and a secondary low-pressure filter that is provided downstream of the low-pressure side of the pressure regulator, and a mounting member that is attached to the fuel tank for a saddle-type multi-characteristic fuel vehicle so as to cover at least a portion of the mounting hole, thereby positioning the fuel pump in the fuel tank for a saddle-type multi-characteristic fuel vehicle, wherein the primary low-pressure filter and the secondary low-pressure filter do not have a pressure retaining structure and constitute a low-pressure filter assembly that enters the fuel tank for a saddle-type multi-characteristic fuel vehicle from the mounting hole together with the pressure regulator and the fuel pump, and The fuel pump or the mounting member is provided so as to determine the positional relationship between the clean side of the secondary low-pressure filter as the starting point of a low-pressure free flow path portion for adjusting the degree of mixing of fuel in the fuel tank for a saddle-type multi-characteristic fuel vehicle in the filtered fuel circulation flow path, and the dirty side of the primary low-pressure filter as the end point.

2. A straddle-type multi-characteristic fuel vehicle as described in claim 1, wherein the pressure regulator is provided on the fuel pump or the mounting member so that the positional relationship between the pressure regulator, the clean side of the secondary low-pressure filter as the starting point of the low-pressure free flow passage portion, and the dirty side of the primary low-pressure filter as the end point is determined.

3. A straddle-type multi-property fuel vehicle as claimed in claim 1 or 2, wherein the primary low-pressure filter and the secondary low-pressure filter each have a fixed shape and are flexible.

4. A saddle-type multi-characteristic fuel vehicle as described in any one of claims 1 to 3, wherein the primary low-pressure filter and the secondary low-pressure filter are provided on the fuel pump or the mounting member such that the fuel pump is not present between the primary low-pressure filter and the secondary low-pressure filter in a direction in which the primary low-pressure filter and the secondary low-pressure filter overlap at least partially.

5. A saddle-type multi-characteristic fuel vehicle as claimed in any one of claims 1 to 3, wherein the primary low-pressure filter and the secondary low-pressure filter are provided on the fuel pump or the mounting member such that at least a portion of the fuel pump is present between the primary low-pressure filter and the secondary low-pressure filter in a direction in which at least a portion of the primary low-pressure filter and the secondary low-pressure filter overlap.

6. A saddle-type multi-characteristic fuel vehicle as claimed in any one of claims 1 to 5, wherein the primary low-pressure filter and the secondary low-pressure filter are provided on the fuel pump or the mounting member such that the primary low-pressure filter is positioned closer to a bottom surface of the fuel tank for the saddle-type multi-characteristic fuel vehicle than the secondary low-pressure filter.

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