Work machine

Abstract

The present invention comprises: an engine that can be driven by each of a plurality of types of fuel including carbon neutral fuel; a fuel tank; a supply pipe that supplies fuel from the fuel tank to the engine; an identification sensor 10 that has a measurement unit 24 and a calculation unit 25 and identifies the fuel; and a sub-tank 38 that is provided to the supply pipe. The sub-tank 38 has a body through which the fuel passes, a fuel inlet 41 which is provided to the body and into which the fuel flows, and a fuel outlet 42 that is provided to the body and discharges the fuel in a direction different from the fuel inlet 41. The measurement unit 24 is provided inside the body, and the calculation unit 25 is provided to a side surface of the body on which the fuel inlet 41 and the fuel outlet 42 are not provided.

Description

Work machine

[0001] The present invention relates to a work machine equipped with an engine driven by a carbon-neutral fuel.

[0002] There is a work machine equipped with an engine that can be driven by a plurality of types of carbon-neutral fuels, and further by a mixed fuel of a plurality of different carbon-neutral fuels. Such an engine can be driven by at least either a predetermined carbon-neutral fuel or a carbon-neutral fuel with a predetermined mixing ratio.

[0003] In such an engine, if an inappropriate fuel other than the drivable fuel is used, engine problems such as engine failure may occur.

[0004] In order to use an appropriate fuel, in the construction machine described in Patent Document 1, a sensor for detecting the physical quantity of the fuel is provided. Further, various devices may be attached to the supply path for supplying fuel to the engine.

[0005] Japanese Unexamined Patent Application Publication No. 2011-94549

[0006] However, there is a need to more accurately identify the fuel by the sensor and to efficiently arrange the devices.

[0007] To achieve the above object, a work machine according to an embodiment of the present invention includes an engine that can be driven by each of a plurality of types of fuels including a carbon-neutral fuel, a fuel tank that stores the fuel, a supply pipe that supplies the fuel from the fuel tank to the engine, a measurement unit that acquires predetermined measurement information regarding the fuel, and an arithmetic unit that performs an arithmetic operation for identifying the fuel based on the measurement information, an identification sensor for identifying the fuel, and a sub-tank provided in the supply pipe, the sub-tank having a main body through which the fuel passes, a fuel inlet provided in the main body through which the fuel flows in, and a fuel outlet provided in the main body that discharges the fuel in a direction different from the fuel inlet, the measurement unit being provided inside the main body, and the arithmetic unit being provided on a side surface of the main body where the fuel inlet and the fuel outlet are not provided.

[0008] With this configuration, fuel is temporarily stored in a sub-tank, and the identification sensor can identify the fuel stored in the sub-tank. Therefore, the identification sensor can identify the fuel even when the fuel flow velocity is low, allowing for accurate fuel identification. In this case, since the fuel is supplied to the sub-tank upward against gravity, the fuel flow velocity can be accurately reduced, allowing for accurate fuel identification. Furthermore, since the identification sensor is positioned to intersect with the direction of fuel flow in the sub-tank, it can accurately identify the flowing fuel.

[0009] Furthermore, the supply pipe may further include equipment having a predetermined function, provided between the fuel tank and the engine, wherein the supply pipe has a return pipe connected to the fuel inlet and the fuel tank, and connected to the fuel outlet and the equipment, and connected to the equipment and the engine, for which the fuel returns from the engine to the fuel tank, and a branch pipe for which the fuel flows from the equipment to the return pipe, and the fuel going from the equipment to the engine may flow through the supply pipe, and the fuel returning from the equipment to the fuel tank may flow through the branch pipe and then through the return pipe.

[0010] If the identification sensor is damaged and fragments of the sensor travel through the fuel to the engine, engine malfunctions such as engine failure may occur. By installing a device between the identification sensor and the engine, even if the identification sensor is damaged, the fragments of the identification sensor will remain in the device and will be prevented from reaching the engine. As a result, engine malfunctions can be prevented.

[0011] The device may also be a fuel filter that removes foreign matter from the fuel supplied to the engine.

[0012] With this configuration, the fuel filter can remove foreign matter from the fuel, thus removing fragments of the identification sensor from the fuel and accurately preventing those fragments from reaching the engine.

[0013] Furthermore, the fuel inlet may be located below the sub-tank in the direction of gravity, with respect to the fuel outlet, across the sub-tank.

[0014] With this configuration, fuel is supplied to the sub-tank from bottom to top, against gravity, which allows for a precise reduction in fuel flow velocity and precise identification of the fuel.

[0015] Furthermore, the fuel inlet may be positioned in a direction that intersects with the direction of gravity and the insertion direction of the identification sensor.

[0016] This configuration allows the fuel inflow and outflow directions to intersect, enabling a precise reduction in fuel flow velocity within the sub-tank. As a result, the identification sensor can accurately identify the fuel. Furthermore, because the identification sensor is positioned in a direction that intersects both the fuel inflow and outflow directions, the measuring section of the identification sensor is inserted in a direction that intersects with the flowing fuel, allowing for even more accurate fuel identification.

[0017] Furthermore, the fuel inlet may be located on the sub-tank, facing the identification sensor across the sub-tank.

[0018] This configuration places the identification sensor and fuel inlet on opposing surfaces of the sub-tank, creating space around the other surfaces of the sub-tank. As a result, the flexibility of placement for the sub-tank equipped with the identification sensor can be improved.

[0019] Furthermore, in the sub-tank, the position where the fuel flows in from the fuel inlet may be lower than the position where the fuel is discharged from the fuel outlet.

[0020] With this configuration, fuel is supplied to the sub-tank from bottom to top, against gravity, which allows for a precise reduction in fuel flow velocity and precise identification of the fuel.

[0021] Furthermore, a work machine according to one embodiment of the present invention comprises an engine capable of being driven by each of a plurality of types of fuel, including carbon neutral fuel; a fuel tank for storing the fuel; a supply pipe for supplying the fuel from the fuel tank to the engine; an identification sensor for identifying the carbon neutral fuel; a base portion including a fuel inlet into which the fuel flows in and a fuel outlet for discharging the fuel; and equipment having a predetermined function, wherein the base portion has a mounting portion for attaching the equipment.

[0022] This configuration allows for easy attachment of equipment to the base unit that discharges the incoming fuel. Therefore, equipment that performs a predetermined function on the fuel can be easily installed near the flowing fuel, and the equipment can perform its function with precision.

[0023] Furthermore, the base portion may include a fuel passage portion that forms the fuel inlet and fuel outlet, and a storage portion provided in the fuel passage portion for storing the fuel, and the mounting portion may be attached to the fuel passage portion.

[0024] This configuration allows the equipment to be mounted in an efficient location depending on the situation. Therefore, the equipment can perform its function with precision.

[0025] Furthermore, the base portion may include a fuel passage portion that forms the fuel inlet and fuel outlet, and a storage portion provided in the fuel passage portion for storing the fuel, and the mounting portion may be attached to the storage portion.

[0026] This configuration allows the equipment to be mounted in an efficient location depending on the situation. Therefore, the equipment can perform its function with precision.

[0027] Furthermore, the base portion further includes a fuel return port for discharging fuel to return it to the fuel tank, a return pipe for returning fuel from the engine to the fuel tank, and a branch pipe for circulating fuel from the equipment to the return pipe, wherein the fuel from the fuel outlet toward the engine circulates through the supply pipe, and the fuel from the fuel return port toward the fuel tank circulates through the branch pipe and the return pipe.

[0028] In this configuration, the fuel supplied to the engine is delivered via a device. Therefore, the fuel that has undergone a predetermined process by the device is supplied to the engine.

[0029] Furthermore, the identification sensor may be provided on a side surface of the base portion that intersects the direction of gravity.

[0030] In fuel passages, fuel often flows out from the upper side in the direction of gravity. By positioning identification sensors on the sides of the fuel passages, the sensors can accurately identify fuel whose flow velocity has been reduced in the fuel passages.

[0031] The device may also be a fuel filter that removes foreign matter from the fuel.

[0032] With this configuration, the fuel filter can remove foreign matter from the fuel, thus removing fragments of the identification sensor from the fuel and accurately preventing those fragments from reaching the engine.

[0033] This is a diagram illustrating the overall configuration of a rice transplanter, which is a work machine. This is a diagram illustrating the overall configuration of a tractor, which is a work machine. This is a diagram illustrating the overall configuration of a backhoe, which is a work machine. This is a diagram illustrating the relationship between the fuel supply path to the engine and the identification sensor. This is a diagram illustrating the operation flow of the identification sensor. This is a cross-sectional view illustrating the configuration of an identification sensor installed in a sub-tank. This is a diagram illustrating the positional relationship between the fuel inlet and fuel outlet in the sub-tank. This is a diagram illustrating the positional relationship between the fuel inlet and fuel outlet in the sub-tank. This is a diagram illustrating an example of a configuration in which the fuel filter, sub-tank, and identification sensor are integrated. This is a schematic diagram showing a cross-section of a part of the fuel flow configuration in an example of a configuration in which the fuel filter, sub-tank, and identification sensor are integrated. This is a diagram illustrating the arrangement relationship between the fuel flow path and the fuel filter. This is a diagram illustrating the arrangement relationship between the fuel flow path and the fuel filter. This is a diagram illustrating the arrangement relationship between the fuel flow path and the fuel filter.

[0034] [Agricultural Machinery] As shown in Figure 1, agricultural machinery such as rice transplanters 2, tractors 3, and backhoes 4, which perform specific tasks including farm work, are equipped with working devices for their respective tasks. The working devices are operated by power supplied from a power source such as an engine 6. Therefore, each agricultural machine is equipped with an engine 6 that outputs power and a fuel tank 8 that stores the fuel supplied to the engine 6.

[0035] Some engines 6 operate only on specific fuels such as gasoline or diesel. On the other hand, some engines 6 can use multiple types of fuel. For example, an engine 6 can be powered by several types of fuel, including carbon-neutral fuels. Such engines 6 can operate on biofuels, synthetic fuels, and can use several specific types of fuel, including carbon-neutral fuels. Some can also use fuels that are mixtures of such fuels in predetermined proportions (mixing ratios).

[0036] In other words, such an engine 6 can use a specific set of fuels, but cannot use any other fuels. If an unsuitable fuel is supplied to the engine 6, problems such as engine failure will occur. Therefore, it is preferable that a work machine equipped with such an engine 6 be provided with an identification sensor 10 (see Figure 4) that identifies the fuel supplied to the engine 6.

[0037] Engine 6 can use various fuels, including diesel fuel, biofuels such as HVO (Hydrotreated Vegetable Oil) and biodiesel fuel, synthetic fuels, and mixtures thereof.

[0038] [Placement of Identification Sensor] As shown in Figure 4, the fuel stored in the fuel tank 8 flows through the fuel flow pipe 12 connected to the fuel tank 8 and the engine 6. In other words, the fuel flow pipe 12 is connected to the fuel tank 8 and the engine 6, and fuel flows through it. Specifically, the engine 6 is equipped with an engine supply pump 6A, and the fuel flow pipe 12 is connected across the fuel tank 8 and the engine supply pump 6A. The engine supply pump 6A draws fuel stored in the fuel tank 8 and delivers it to the engine 6 via the fuel flow pipe 12.

[0039] The fuel supply pipe 12 includes a supply pipe 13 and a return pipe 14. The supply pipe 13 is the path for supplying fuel from the fuel tank 8 to the engine 6 (engine supply pump 6A). The return pipe 14 is the path for returning fuel from the engine 6 to the fuel tank 8. The supply pipe 13 is equipped with a fuel filter 18 that removes foreign matter from the fuel supplied to the engine 6. In addition to the supply pipe 13 and the return pipe 14, the fuel supply pipe 12 also includes a branch pipe 15 that allows fuel to flow from the fuel filter 18 to the return pipe 14. At least a portion of the fuel from which foreign matter has been removed by the fuel filter 18 is supplied from the fuel filter 18 to the engine 6 (engine supply pump 6A) via the supply pipe 13. The remaining fuel is returned from the fuel filter 18 to the fuel tank 8 via the branch pipe 15 and the return pipe 14.

[0040] The identification sensor 10 identifies at least one of the following: the type of fuel supplied to the engine 6 and its mixing ratio. The type of fuel is whether it is diesel fuel, biofuel such as HVO or biodiesel fuel, or synthetic fuel, or it is a specific type of fuel. In other words, the identification sensor 10 identifies whether the fuel is a carbon-neutral fuel or a fuel other than a carbon-neutral fuel such as diesel fuel, and may also identify which type of carbon-neutral fuel it is. Furthermore, if the fuel is a mixture of carbon-neutral fuels (blended fuel), the identification sensor 10 identifies the mixing ratio of the carbon-neutral fuels along with the type of carbon-neutral fuel. Note that carbon-neutral fuels include synthetic fuels, e-fuel, biofuel, and hydrogen, and the identification sensor 10 may identify which of these the fuel is. Here, e-fuel is a fuel produced using hydrogen derived from renewable energy.

[0041] As shown in Figures 5 and 6, the identification sensor 10 includes a measurement unit 24 that acquires (measures and detects) predetermined measurement information 51 related to fuel, and a calculation unit 25 that performs calculations to identify the fuel based on the measurement information 51. In other words, the calculation unit 25 identifies the fuel by performing predetermined calculations based on the measurement information 51 acquired by the measurement unit 24. The calculation unit 25 then outputs identification information 52 as the calculation result (the result of identification).

[0042] As shown in Figure 4, the identification sensor 10 is directly installed in the fuel flow pipe 12. Specifically, the identification sensor 10 is installed in the supply pipe 13, and more specifically, the identification sensor 10 is installed between the fuel tank 8 and the fuel filter 18 in the supply pipe 13. As a result, identification processing is performed on the fuel supplied to the engine 6, enabling accurate identification of the fuel.

[0043] In addition, if the identification sensor 10 provided in the supply pipe 13 is damaged, fragments of the identification sensor 10 may enter the engine 6, which may cause problems such as malfunctions or damage in the engine 6. Therefore, by providing the identification sensor 10 between the fuel tank 8 and the fuel filter 18 of the supply pipe 13 (upstream of the fuel filter 18), even if the identification sensor 10 is damaged, the fragments are intercepted by the fuel filter 18 (or any device described later), and it is suppressed from being supplied to the engine 6.

[0044] Also, the fuel returned from the engine 6 is heated by the engine 6 or minute bubbles are generated, and in some cases, the identification sensor 10 may not be able to accurately identify the fuel. Therefore, by providing the identification sensor 10 in the supply pipe 13, particularly between the fuel tank 8 and the fuel filter 18 of the supply pipe 13, rather than in the return pipe 14, the fuel can be accurately identified.

[0045] Further, the identification sensor 10 may be provided in the return pipe 14, or may be provided between the engine 6 and the branch pipe 15 (position 21) of the return pipe 14. With such a configuration, when the temperature of the fuel and minute bubbles are not a problem, the degree of freedom in the arrangement position of the identification sensor 10 is increased.

[0046] Note that both the measurement unit 24 and the calculation unit 25 of the identification sensor 10 may be provided in the fuel flow pipe 12, but at least the measurement unit 24 of the identification sensor 10 may be provided in the fuel flow pipe 12, and the calculation unit 25 may be provided at a position different from the fuel flow pipe 12. Thereby, the measurement unit 24 that needs to contact the fuel is provided in the fuel flow pipe 12, and the calculation unit 25 can be provided in the fuel flow pipe 12 or any other arbitrary location, so that the fuel can be accurately identified while efficiently arranging the identification sensor 10.

[0047] [Display of Identification Result] Next, a configuration for displaying the identification result will be described using FIGS. 1 to 5.

[0048] The identification sensor 10 outputs the identification result as identification information 52. Specifically, the arithmetic unit 25 of the identification sensor 10 outputs the identification information 52. And preferably, the working machine includes a display device that acquires and displays the identification information 52 output by the identification sensor 10. The display device may be provided independently on the working machine, but the identification information 52 may also be displayed on the display unit of the information terminal 27 provided in the working machine. The information terminal 27 is detachably provided on the machine body and is a terminal that allows an operator to perform various settings and operations and display various information to the operator.

[0049] As described above, the engine 6 according to the present embodiment can use a plurality of types of fuels. That is, there are fuels that can be used in the engine 6 and fuels that cannot be used in the engine 6, and the identification sensor 10 can identify which fuel is supplied to the engine 6. And by displaying the identification result on the display unit, the operator can determine whether an appropriate fuel is being used, and if an inappropriate fuel is being used, can take measures such as stopping the engine 6. As a result, driving of the engine 6 with an inappropriate fuel can be suppressed.

[0050] At this time, the working machine may further include a control unit 29 that controls the operation of the engine 6. And the control unit 29 stops the engine 6 when the identification information 52 is in a predetermined state. For example, when the identification information 52 indicates that an inappropriate fuel is being used, the control unit 29 stops the engine 6. Note that depending on the fuel, the engine 6 may not be unable to use it, but there are also fuels that are not recommended for use. For example, such fuels may load the engine 6. When the identification result indicates such a fuel, instead of stopping the engine 6, the control unit 29 may limit the output of the engine 6 or issue a predetermined warning. Thereby, the working machine can suppress the engine 6 from being loaded while using as many types of fuels as possible.

[0051] If the fuel is a mixture of multiple carbon-neutral fuels, the identification information 52 preferably includes at least one of the types of carbon-neutral fuels to be mixed, the mixing ratio of the carbon-neutral fuels, and the carbon dioxide reduction effect.

[0052] As a result, even in an engine 6 that can use a mixture of multiple carbon-neutral fuels as fuel, the types of carbon-neutral fuels to be mixed and the mixing ratio of the carbon-neutral fuels are displayed, making it possible to determine whether or not the fuel is usable in the engine 6. As a result, it is possible to prevent the engine 6 from being driven with an inappropriate fuel. In the case of a single carbon-neutral fuel, the identification information 52 may be configured to include either the type of carbon-neutral fuel or the carbon dioxide reduction effect.

[0053] Furthermore, carbon-neutral fuels generally produce less carbon dioxide emissions than diesel fuel. The degree of reduction in carbon dioxide emissions (reduction effect) varies depending on the type of carbon-neutral fuel. The carbon dioxide reduction effect is one of the reasons for using carbon-neutral fuels. By displaying the carbon dioxide reduction effect, consumers can confirm the significance of using carbon-neutral fuels and easily select fuels with a higher carbon dioxide reduction effect.

[0054] [Warning] Along with the above display, or instead of displaying the above, a predetermined warning may be issued depending on the identification result. The following describes a configuration in which a predetermined warning is issued depending on the identification result, using Figures 1 to 5.

[0055] The work machine may issue a predetermined warning according to the identification result identified by the identification sensor 10. For this purpose, the work machine may further be equipped with a lamp 31 and a speaker 32 as warning units that issue predetermined warnings. Alternatively, an information terminal 27 or display device may also act as a warning unit to issue a warning. The work machine further includes a determination unit 34 that determines whether a warning is necessary according to the identification information 52, and a warning control unit 35 that causes the warning unit to issue a warning according to the determination unit 34's determination. When the determination unit 34 determines that a warning is necessary, the warning control unit 35 causes at least one of the information terminal 27, lamp 31, and speaker 32 to issue a warning. This allows the operator to determine whether the appropriate fuel is being used and to take measures such as stopping the engine 6 if inappropriate fuel is being used. As a result, it is possible to suppress the operation of the engine 6 with inappropriate fuel.

[0056] When a warning is issued using the information terminal 27 or display device, the display unit of the information terminal 27 displays images such as animations corresponding to the warning, or text data such as warning messages. When a warning is issued using the lamp 31, the warning is issued by flashing or lighting the lamp 31. The flashing, lighting, and patterns of these can give meaning to the warning. For example, a flashing lamp 31 can be a warning that unusable fuel is being supplied, and a lit lamp 31 can be a warning that mixed fuel is being supplied. When a warning is issued using the speaker 32, a warning sound or voice message indicating the warning is output from the speaker 32.

[0057] This configuration allows for detailed information about the identification results to be communicated to the operator. For example, it not only indicates whether or not the fuel is usable in engine 6, but also what type of carbon-neutral fuel is being supplied, whether it is a mixed fuel, which carbon-neutral fuel is being used if it is, and the mixing ratio. The carbon dioxide reduction effect may also be reported. Furthermore, if it is a mixed fuel, the determination unit 34 determines that a warning is necessary if the mixing ratio falls outside a predetermined range of mixing ratios usable in engine 6, and the warning control unit 35 issues a predetermined warning when the determination unit 34 determines that a warning is necessary. With this configuration, more detailed information about the supplied fuel is provided, and the operation of engine 6 with inappropriate fuel can be suppressed with greater accuracy.

[0058] [Another Embodiment] (1) In the above embodiment, as shown in Figures 4 to 6, the work machine may be equipped with a sub-tank 38 in the fuel flow pipe 12, and the identification sensor 10 may be connected to the sub-tank 38. For example, the sub-tank 38 to which the identification sensor 10 is connected may be placed at any position in the fuel flow pipe 12, but as described above, it is preferable to place it in the supply pipe 13, and more preferably between the fuel tank 8 and the fuel filter 18 in the supply pipe 13. In other words, it is preferable to place the fuel filter 18 (device described later) between the sub-tank 38 (identification sensor 10) and the engine 6.

[0059] The sub-tank 38 has a main body through which fuel passes, a fuel inlet 41 provided in the main body through which fuel flows, and a fuel outlet 42 provided in the main body for discharging fuel in a direction different from that of the fuel inlet 41.

[0060] For example, the sub-tank 38 is equipped with an identification space 39, a fuel inlet 41, and a fuel outlet 42 in its main body. The identification space 39 is a space provided inside the sub-tank 38 and is the region through which the fuel passes. The fuel inlet 41 is the inlet through which the fuel flows into the main body (identification space 39) and is connected to the fuel flow pipe 12, allowing the fuel flowing through the fuel flow pipe 12 to flow into the identification space 39 of the sub-tank 38. The fuel outlet 42 is the outlet for discharging fuel from the main body (identification space 39) and is connected to the fuel flow pipe 12, discharging the fuel that has flowed into the identification space 39 back into the fuel flow pipe 12.

[0061] The identification sensor 10 is inserted into the sub-tank 38 such that at least the measuring unit 24 is located inside the identification space 39 (main body) of the sub-tank 38. In this case, the calculation unit 25 of the identification sensor 10 may be exposed (placed) outside the sub-tank 38, or it may be located inside the sub-tank 38, and the calculation unit 25 may be placed at any position on the work machine. For example, the calculation unit 25 may be provided on the side of the main body (identification space 39) where the fuel inlet 41 and fuel outlet 42 are not provided.

[0062] As described above, a sub-tank 38 having an identification space 39 is provided in the fuel flow pipe 12, and the identification sensor 10 is installed in the sub-tank 38 in such a manner that the measuring unit 24 is inserted into the identification space 39 (main body). The fuel flowing through the fuel flow pipe 12 is temporarily stored in the identification space 39 (main body) of the sub-tank 38, causing its flow velocity to decrease. Therefore, the identification sensor 10, with its measuring unit 24 inserted into the identification space 39, can make sufficient contact with the fuel and accurately identify the fuel. As a result, the fuel can be identified with high accuracy.

[0063] Here, it is preferable that the fuel outlet 42 discharges fuel in a direction different from that of the fuel inlet 41. For example, it is preferable that the fuel outlet 42 discharges fuel from the sub-tank 38 (identification space 39) upward in the direction of gravity G. This allows the fuel to flow against gravity, making it easy to reduce the fuel flow velocity within the identification space 39 (main body). It is also preferable that the fuel inlet 41 allows fuel to flow into the sub-tank 38 (identification space 39) from a direction different from that of the fuel outlet 42. This makes it even easier to reduce the fuel flow velocity within the identification space 39 (main body).

[0064] In particular, as shown in Figure 6, it is preferable that the fuel inlet 41 is located below the sub-tank 38 in the direction of gravity G, with respect to the fuel outlet 42, across the sub-tank 38. This allows fuel to flow from bottom to top against gravity within the sub-tank 38, temporarily stored in the identification space 39 along the way, and the fuel overflowing from the identification space 39 flows towards the fuel outlet 42. As a result, the measuring unit 24 can come into contact with the fuel that has almost stopped or whose flow velocity has been sufficiently reduced within the identification space 39, allowing for fuel identification (measurement of measurement information 51 (see Figure 5)). Consequently, fuel can be identified with high accuracy.

[0065] Furthermore, as shown in Figure 7, the fuel inlet 41 may be positioned so as to intersect with the direction of gravity G and the direction in which the identification sensor 10 is inserted. In other words, the fuel inlet 41 is positioned so as to intersect with the direction of fuel flow at the fuel outlet 42 (direction of gravity G) and the direction in which the identification sensor 10 is inserted. More specifically, if the surface on which the identification sensor 10 is installed is the lateral side surface and the surface on which the fuel outlet 42 is installed is the circumferential surface, the fuel inlet 41 is installed on the circumferential surface, not at the location where the fuel outlet 42 is installed, nor on the back surface of the location where the fuel outlet 42 is installed. Even with such a configuration, the measuring unit 24 can come into contact with the fuel whose flow velocity has been sufficiently reduced in the identification space 39, and perform fuel identification (measurement of measurement information 51 (see Figure 5)). As a result, the fuel can be identified with high accuracy.

[0066] Furthermore, as shown in Figure 8, the fuel inlet 41 may be located on the sub-tank 38, facing the identification sensor 10 across the sub-tank 38. In other words, the fuel inlet 41 is located on the back surface of the sub-tank 38 relative to the identification sensor 10, that is, in a position facing the identification sensor 10 on the sub-tank 38. Even with this configuration, the measuring unit 24 can come into contact with the fuel, whose flow velocity has been sufficiently reduced within the identification space 39, and perform fuel identification (measurement of measurement information 51 (see Figure 5)). As a result, the fuel can be identified with high accuracy.

[0067] Furthermore, as shown in Figures 6 to 8, it is preferable that the position where fuel flows in from the fuel inlet 41 to the sub-tank 38 is lower than the position where fuel is discharged from the fuel outlet 42. This allows the fuel to flow from bottom to top against gravity within the sub-tank 38, temporarily storing in the identification space 39 along the way, and the fuel overflowing from the identification space 39 flows towards the fuel outlet 42. As a result, the measuring unit 24 can come into contact with the fuel that has almost stopped or whose flow velocity has been sufficiently reduced within the identification space 39, allowing for fuel identification (measurement of measurement information 51 (see Figure 5)). Consequently, the fuel can be identified with high accuracy.

[0068] Furthermore, as shown in Figures 6 to 8, the identification sensor 10 may be provided on the side surface of the sub-tank 38 when the gravity direction G of the sub-tank 38 is defined as the vertical direction, with the measuring unit 24 inserted into the identification space 39. In other words, the identification sensor 10 is inserted into the sub-tank 38 from a direction intersecting the direction in which the fuel flows (gravity direction G) through the identification space 39. As a result, the measuring unit 24 extends in a direction intersecting the direction in which the fuel flows, allowing the identification sensor 10 to accurately identify the fuel (measurement of measurement information 51 (see Figure 5)).

[0069] (2) In the above alternative embodiment (1), as shown in Figure 9, the fuel filter 18 (device described later) is provided in the sub-tank 38. In other words, the identification sensor 10, the sub-tank 38, and the fuel filter 18 are provided integrally. With this configuration, the identification sensor 10, the sub-tank 38, and the fuel filter 18 can be efficiently arranged while accurately identifying the fuel.

[0070] The fuel filter 18 is connected to the fuel outlet 45. The sub-tank 38, to which the identification sensor 10 and fuel filter 18 are connected, has a fuel inlet 46 and a fuel return port 47. The fuel outlet 45 is connected to a fuel flow pipe 12 (supply pipe 13) that discharges fuel toward the engine 6. The fuel inlet 46 is connected to a fuel flow pipe 12 (supply pipe 13) that allows fuel to flow from the fuel tank 8 into the sub-tank 38. The fuel return port 47 is connected to a fuel flow pipe 12 (branch pipe 15) that allows fuel to flow from the sub-tank 38 back to the fuel tank 8.

[0071] In other words, fuel from the fuel outlet 45 toward the engine 6 flows through the supply pipe 13, and fuel from the fuel return port 47 of the sub-tank 38 toward the fuel tank 8 flows through the branch pipe 15 and then the return pipe 14. This configuration allows for efficient fuel distribution.

[0072] The identification sensor 10 is preferably provided on a side surface of the sub-tank 38 that intersects with the direction of gravity G (see Figure 6), similar to the other embodiment (1) (see Figures 6 to 9). For example, the sub-tank 38 and the fuel filter 18 can be connected side by side in the vertical direction (direction of gravity G), and the identification sensor 10 can be connected to the side of the sub-tank 38.

[0073] As shown in Figure 10, the fuel flowing in from the fuel inlet 46 flows into the inlet space 49 of the sub-tank 38, a portion of which reaches the identification space 39, and the remainder flows into the fuel filter 18 and is stored there. After the fuel that has flowed into the sub-tank 38 is identified by the identification sensor 10, it is discharged from the fuel return port 47 and returns to the fuel tank 8 via the branch pipe 15 and the return pipe 14. The fuel stored in the fuel filter 18 has foreign matter removed and is discharged from the fuel outlet 45 and supplied to the engine 6 via the supply pipe 13.

[0074] With this configuration, the fuel flowing in from the fuel inlet 46 is distributed to the identification sensor 10 and the fuel filter 18. Most of the fuel used for identification by the identification sensor 10 in the sub-tank 38 is returned to the fuel tank 8 via the fuel return port 47, and any fuel that is headed for the engine 6 flows to the engine 6 via the fuel filter 18. Therefore, only fuel from which foreign matter has been removed by the fuel filter 18 is supplied to the engine 6. Even if the identification sensor 10 is damaged, its fragments are removed from the fuel by the fuel filter 18, preventing them from reaching the engine 6. As a result, fuel can be identified accurately while suppressing malfunctions in the engine 6.

[0075] The fuel outlet 45 and fuel return port 47 may open in any direction, but it is preferable that they open upward (in the direction of gravity G). This allows the fuel to be discharged against gravity, making it easier to control the flow rate and enabling precise adjustment of the amount of fuel supplied to the engine 6 and the amount of fuel supplied to the identification space 39. As a result, the operation of the engine 6 can be controlled with precision, and the fuel can be identified with precision.

[0076] Furthermore, the identification sensor 10 and the fuel inlet 46 may be placed at any position on the sub-tank 38, or they may be provided on the side of the sub-tank 38. The direction of fuel inflow at the fuel inlet 46 may be in a direction that intersects with the direction in which the measuring unit 24 of the identification sensor 10 is inserted into the sub-tank 38, or it may be in a parallel direction. In other words, the positional relationship between the identification sensor 10 and the fuel inlet 46 on the side of the sub-tank 38 may be any positional relationship. Also, fuel may flow through the fuel inlet 46 from a direction that intersects with the direction in which fuel flows through the fuel outlet 45 and the fuel inlet 46 (gravity direction G), or it may flow from the same direction.

[0077] (3) In the above alternative embodiment (2), the sub-tank 38 may not be provided. In this case, the identification sensor 10 and the fuel filter 18 can be provided at any position.

[0078] For example, as shown in Figure 11, instead of the sub-tank 38, a base unit 55 is provided, which includes a fuel inlet 46 into which fuel flows and a fuel outlet 45 for discharging fuel. The base unit 55 has a mounting portion 56 to which a fuel filter 18 (a device described later) is attached. In other words, the fuel filter 18 is installed on the base unit 55 via the mounting portion 56.

[0079] The base portion 55 is a component that forms a flow path through which fuel flows in from the fuel inlet 46 and is discharged from the fuel outlet 45. The base portion 55 may also include a fuel filter 18. The identification sensor 10 can be provided on the base portion 55. The fuel flowing through the base portion 55 flows to the fuel filter 18 via the mounting portion 56.

[0080] This configuration allows for the efficient placement of the fuel filter 18 and the identification sensor 10. Furthermore, the fuel filter 18 (device) can be easily attached to the base unit 55. Because the fuel filter 18 is located in the base unit 55 through which fuel flows, the fuel filter 18 can accurately remove foreign matter from the fuel.

[0081] Furthermore, as shown in Figure 12, the base portion 55 may also include a fuel passage portion 58 and a storage portion 59. The fuel passage portion 58 is a member in which a fuel inlet 46 and a fuel outlet 45 are formed, and a flow path is formed through which fuel flows in from the fuel inlet 46 and is discharged from the fuel outlet 45. The storage portion 59 is an optional member provided in the fuel passage portion 58 for storing fuel. The mounting portion 56 for attaching the fuel filter 18 to the base portion 55 may also be provided in the fuel passage portion 58. In other words, the fuel filter 18 is provided in the base portion 55 via the mounting portion 56 of the fuel passage portion 58. The positional relationship between the storage portion 59 and the fuel filter 18 is arbitrary. Moreover, in Figures 11 and 12, the fuel filter 18 may not be provided, and only the storage portion 59 may be provided. This makes it possible to have a configuration in which fuel can be identified with the minimum necessary configuration.

[0082] This configuration allows the fuel filter 18 and the identification sensor 10 to be efficiently positioned according to the situation. Furthermore, the fuel filter 18 (device) can be easily attached to the fuel passage section 58. Since the fuel filter 18 is provided in the fuel passage section 58 through which fuel flows, the fuel filter 18 can accurately remove foreign matter from the fuel.

[0083] Furthermore, as shown in Figure 13, the base portion 55 may also include a fuel passage portion 58 and a storage portion 59. The fuel passage portion 58 is a member that forms a fuel inlet 46 and a fuel outlet 45, and forms a flow path through which fuel flows in from the fuel inlet 46 and is discharged from the fuel outlet 45. The storage portion 59 is an optional member provided in the fuel passage portion 58 for storing fuel. The mounting portion 56 for attaching the fuel filter 18 to the base portion 55 may be provided in the storage portion 59. In other words, the fuel filter 18 is provided in the base portion 55 via the mounting portion 56 of the fuel passage portion 58.

[0084] This configuration allows the fuel filter 18 and the identification sensor 10 to be efficiently positioned according to the situation. Furthermore, the fuel filter 18 (device) can be easily attached to the storage section 59. Since the fuel filter 18 is provided in the storage section 59 where the fuel is stored, the fuel filter 18 can accurately remove foreign matter from the fuel.

[0085] (4) In each of the above embodiments, the identification sensor 10 may be provided in multiple locations, not just one. This allows for more accurate identification of the fuel. Furthermore, the identification sensor 10 is not limited to being provided in the supply pipe 13, but may be provided at one or more arbitrary locations in the fuel flow pipe 12. For example, the identification sensor 10 may be provided in either the supply pipe 13 or the return pipe 14, or both. Also, the identification sensor 10 is not limited to being provided between the fuel tank 8 and the fuel filter 18, but may be provided in either the supply pipe 13 between the fuel tank 8 and the fuel filter 18, or between the fuel filter 18 and the engine 6 (location 22), or both. This allows for more flexibility in the placement of the identification sensor 10 while enabling accurate identification of the fuel.

[0086] (5) In each of the above embodiments, the fuel filter 18 may not be provided in the fuel flow pipe 12, the sub-tank 38, or the base unit 55. Alternatively, the fuel flow pipe 12 may be provided with other equipment that performs a predetermined operation (equipment having a predetermined function) instead of the fuel filter 18. Furthermore, a branch pipe 15 may be provided between the equipment and the return pipe 14, and fuel may flow from the equipment to the return pipe 14 via the branch pipe 15, or a branch pipe 15 may not be provided between the equipment and the return pipe 14.

[0087] This allows for easy identification of fuel while providing equipment that performs predetermined operations in the fuel flow pipe 12. Furthermore, the equipment can suppress foreign matter originating from the identification sensor 10, etc., from flowing with the fuel, thereby preventing foreign matter from entering the engine 6.

[0088] (6) In each of the above embodiments, the implement may be an agricultural implement such as a rice transplanter 2 or a tractor 3, or a construction implement, and may also be various engine-driven equipment driven by an engine 6 such as an engine generator or an engine compressor. In other words, the implement may be any self-propelled engine-driven equipment such as an agricultural implement or a construction implement, or it may be a stationary (portable) engine-driven equipment.

[0089] The present invention can be applied to various engine-driven work machines.

[0090] 6 Engine 8 Fuel Tank 10 Identification Sensor 12 Fuel Flow Pipe 13 Supply Pipe 14 Return Pipe 15 Branch Pipe 18 Fuel Filter (Equipment) 24 Measurement Unit 25 Calculation Unit 38 Sub-tank 39 Identification Space G Direction of Gravity 41 Fuel Inlet 42 Fuel Outlet 45 Fuel Discharge Port 46 Fuel Inlet 47 Fuel Return Port 51 Measurement Information 55 Base Unit 56 Mounting Unit 58 Fuel Passage Unit 59 Storage Unit

Claims

1. An engine capable of being driven by each of several types of fuel, including carbon neutral fuel; a fuel tank for storing the fuel; a supply pipe for supplying the fuel from the fuel tank to the engine; an identification sensor for identifying the fuel, having a measuring unit for acquiring predetermined measurement information relating to the fuel and a calculation unit for performing calculations to identify the fuel based on the measurement information; and a sub-tank provided in the supply pipe, wherein the sub-tank has a main body through which the fuel passes, a fuel inlet provided in the main body through which the fuel flows in, and a fuel outlet provided in the main body for discharging the fuel in a direction different from the fuel inlet; the measuring unit is provided inside the main body; and the calculation unit is provided on a side of the main body where the fuel inlet and fuel outlet are not provided.

2. The work machine according to claim 1, further comprising a device having a predetermined function, provided between the fuel tank and the engine in the supply pipe, wherein the supply pipe is connected to the fuel inlet and the fuel tank, and to the fuel outlet and the device, and to the engine, and further comprises a return pipe through which the fuel returns from the engine to the fuel tank, and a branch pipe through which the fuel flows from the device to the return pipe, wherein the fuel going from the device to the engine flows through the supply pipe, and the fuel returning from the device to the fuel tank flows through the branch pipe and then through the return pipe.

3. The work machine according to claim 2, wherein the device is a fuel filter that removes foreign matter from the fuel supplied to the engine.

4. The work machine according to any one of claims 1 to 3, wherein the fuel inlet is located below the sub-tank in the direction of gravity, with respect to the fuel outlet, across the sub-tank.

5. The work machine according to any one of claims 1 to 3, wherein the fuel inlet is provided in a direction that intersects with the direction of gravity and intersects with the insertion direction of the identification sensor.

6. The work machine according to any one of claims 1 to 3, wherein the fuel inlet is provided at a position on the sub-tank that faces the identification sensor across the sub-tank.

7. The work machine according to any one of claims 1 to 6, wherein the position in which the fuel flows in from the fuel inlet to the sub-tank is lower than the position in which the fuel is discharged from the fuel outlet.

8. A work machine comprising: an engine capable of being driven by each of several types of fuel, including carbon neutral fuel; a fuel tank for storing the fuel; a supply pipe for supplying the fuel from the fuel tank to the engine; an identification sensor for identifying the carbon neutral fuel; a base portion including a fuel inlet for the fuel to flow in and a fuel outlet for the fuel to discharge; and equipment having a predetermined function, wherein the base portion has a mounting portion for attaching the equipment.

9. The work machine according to claim 8, wherein the base portion comprises a fuel passage portion that forms the fuel inlet and the fuel outlet, and a storage portion provided in the fuel passage portion for storing the fuel, and the mounting portion is attached to the fuel passage portion.

10. The work machine according to claim 8, wherein the base portion comprises a fuel passage portion that forms the fuel inlet and the fuel outlet, and a storage portion provided in the fuel passage portion for storing the fuel, and the mounting portion is attached to the storage portion.

11. The work machine according to any one of claims 8 to 10, wherein the base portion further comprises a fuel return port for discharging fuel to return the fuel to the fuel tank, a return pipe for returning the fuel from the engine to the fuel tank, and a branch pipe for circulating the fuel from the equipment to the return pipe, wherein the fuel from the fuel discharge port toward the engine circulates through the supply pipe, and the fuel from the fuel return port toward the fuel tank circulates through the branch pipe and the return pipe.

12. The work machine according to any one of claims 8 to 11, wherein the identification sensor is provided on a side surface which is a surface intersecting the direction of gravity of the base portion.

13. The work machine according to any one of claims 8 to 12, wherein the device is a fuel filter that removes foreign matter from the fuel.

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