Method and device for determining fuel abnormality in engine-driven work machine

Abstract

To determine abnormality in fuel, such as contamination with incompatible fuel or degradation due to aging, used in an engine-driven work machine.SOLUTION: In a method for determining fuel abnormality in engine-driven work machine, a predetermined characteristic value (for example an ultrasonic propagation speed) of fuel in use detected at any location (fuel tank 80) in a fuel supply system is acquired as a fuel characteristic value Y (S3) and the fuel characteristic value is compared with a fuel characteristic standard range (Ymin to Ymax) which is preliminarily stored in storage means 21 and represents a range where the characteristic value (ultrasonic propagation speed) of the fuel in use is determined to be normal (S5). When the fuel characteristic value Y is out of the range (Y<Ymin or Y>Ymax) of the fuel characteristic standard range (Ymin to Ymax) of the fuel in use, as a result of comparison (No in S6), the fuel is determined to have abnormality (S9), a warning is issued (S10), and an engine operation is restricted (S11).SELECTED DRAWING: Figure 3

Description

[Technical field]

[0001] The present invention relates to a fuel abnormality determination method and a fuel abnormality determination device for an engine-driven working machine, and more specifically to a fuel abnormality determination method for an engine-driven working machine that determines when the fuel being used in the engine-driven working machine has become abnormal due to, for example, mixing of different types of fuel or deterioration over time, and a fuel abnormality determination device that executes the determination method. [Background technology]

[0002] As society becomes more concerned about environmental issues, the demand for decarbonization is also growing in the civil engineering and construction industries, and there is a demand to reduce carbon dioxide emissions from engine-driven work machines such as engine-driven generators and engine-driven compressors, which are often used in the civil engineering and construction industries.

[0003] In response to these demands, there is a social demand for the fuel used in engine-driven work machinery to be switched from diesel to alternative fuels that emit less carbon dioxide than diesel, such as blended fuels such as B5 diesel, which is diesel with 5% or less biodiesel fuel added, B100 fuel, which is 100% biodiesel fuel, and GTL fuel, which is fuel refined from natural gas.

[0004] Here, under the Local Tax Act, B5 diesel, which is treated as diesel or light oil, is subject to diesel transaction tax, whereas B100 fuel and GTL fuel are not subject to taxation.

[0005] On the other hand, if a mixed fuel produced by mixing diesel or B5 diesel with B100 fuel or GTL fuel falls under the category of "diesel" under the Local Tax Act, it is subject to diesel transaction tax. Therefore, for example, if B100 fuel or GTL fuel is mistakenly filled with diesel or B5 diesel remaining in the fuel tank, or if diesel or B5 diesel is mistakenly filled with B100 fuel or GTL fuel remaining in the fuel tank, and these fuels are mixed in the fuel tank to produce a mixed fuel that falls under the category of "diesel" under the Local Tax Act, the "consumption" of the mixed fuel produced in this way is subject to diesel transaction tax as stipulated in the Local Tax Act (Article 144-3, item 5 of the Local Tax Act), and therefore the "consumption" of the aforementioned mixed fuel that is carried out without paying diesel transaction tax is illegal.

[0006] Therefore, the mixing of other fuels into diesel and B5 diesel should be strictly prevented.

[0007] In addition, so-called "illegal diesel" - diesel mixed with other fuels such as kerosene for the purpose of evading diesel transaction taxes - is also in circulation. If the fuel purchased believing it to be diesel or biodiesel turns out to be such illegal diesel, it is possible that such illegal diesel will be used unintentionally.

[0008] Therefore, in today's world where corporate compliance is strongly required, there is a demand for systems that can prevent the consumption of such mixed fuels (illegal diesel) by, for example, automatically disabling the engine from starting in cases where diesel or B5 diesel is mixed with different types of fuel in the fuel tank, or where a fuel (mixed fuel) of a type different from that recognized by the operator is being refueled.

[0009] In addition, fuel has a recommended usage period; for example, for diesel, this recommended usage period is approximately six months. However, there are some engine-driven work machines that are not normally used and are stored in a stopped state for relatively long periods of time, such as engine-driven generators that are used as backup power sources in the event of a disaster, and it is possible that the fuel in the fuel tank has been stored for a long period of time beyond the recommended usage period.

[0010] In this way, fuel that has been stored for a long period beyond the recommended period of use may have its properties changed due to oxidation, etc., and using fuel with such properties may not only cause poor combustion, but may also cause breakdowns in the engine or fuel supply system.

[0011] For this reason, it is necessary to take measures to prevent engine-driven work machines from being started even if the fuel stored in the fuel tank of the engine-driven work machine has become abnormal, such as changing its properties after being stored for a long period of time.

[0012] In response to such demand, it would be convenient if it were possible to automatically determine if there was an abnormality (fuel abnormality) in the fuel being supplied to engine-driven work machines, such as the mixing of different types of fuel or changes in properties due to deterioration over time, and take measures such as restricting the starting of the engine.

[0013] Although it does not determine fuel abnormalities as described above, Patent Document 1 listed below proposes equipping a vehicle with a biofuel identification device that can identify the type of biofuel and the mixture ratio of diesel and biofuel in order to control post-injection during regeneration of a diesel particulate filter according to the mixture ratio of biofuel.

[0014] This biofuel identification device is equipped with a fuel oxygen concentration detection means for detecting the oxygen concentration in the fuel supplied to the combustion device, and a heat value acquisition means for acquiring the heat value generated by the fuel per process. Based on the previously acquired correspondence between the oxygen concentration in the fuel and the blending ratio of biofuel to diesel, and the correspondence between the heat value and the blending ratio of biofuel to diesel, the device compares the blending ratio based on the detected oxygen concentration in the fuel with the blending ratio based on the acquired heat value of the fuel, and identifies a biofuel type whose blending ratios approximately match as the biofuel type in use, and identifies that blending ratio as the blending ratio of biofuel in the biofuel blended diesel ([Claim 1] of Patent Document 1). [Prior art documents] [Patent documents]

[0015] [Patent Document 1] JP 2011-149297 A Summary of the Invention [Problem to be solved by the invention]

[0016] The biofuel identification device introduced in Patent Document 1 above can automatically identify the type of biofuel in the fuel being used and the mixing ratio of biofuel to diesel. However, since it identifies the type of biofuel and the mixing ratio of diesel to biofuel without knowing anything about the type of fuel being used, in order to make these identifications it is always necessary to have a means for detecting the oxygen concentration in the fuel and to obtain the amount of heat generated by the fuel per process, and so on, and since it is necessary to identify the type of biofuel by combining multiple characteristics of the fuel, complex device configurations and complex calculation processing, etc.

[0017] In particular, in order to identify the type of biofuel, it is necessary to obtain the oxygen concentration-mixing ratio characteristics in the fuel and the heat value-mixing ratio characteristics for each type of biofuel, which makes the device configuration and detection processing even more complicated.

[0018] Moreover, while the configuration described in the above-mentioned Patent Document 1 is capable of detecting the type of biofuel and the mixing ratio of diesel and biofuel, it is not capable of determining the occurrence of fuel abnormalities such as the mixing of different fuels or deterioration over time that occurs in diesel, B5 diesel, B100 fuel, GTL fuel, etc.

[0019] Therefore, it is desirable to have a relatively simple device configuration that can determine when an abnormality occurs in the fuel being used in an engine-driven work machine.

[0020] Therefore, the present invention has been made to eliminate the drawbacks of the above-mentioned conventional technology, and aims to provide a fuel abnormality determination method for engine-driven working machines that can determine when a fuel abnormality has occurred in the fuel used in the engine-driven working machine, such as the mixing of a different type of fuel or a change in properties due to deterioration over time, and a fuel abnormality determination device for engine-driven working machines that executes the determination method. [Means for solving the problem]

[0021] The means for solving the problems are described below together with the reference numerals used in the description of the embodiment of the invention. These reference numerals are described in order to clarify the correspondence between the description of the claims and the description of the embodiment of the invention, and needless to say, are not used to restrict the interpretation of the technical scope of the present invention.

[0022] In order to achieve the above object, the fuel abnormality determination method of the engine-driven working machine 1 of the present invention includes the following steps: In a method for determining a fuel abnormality in an engine-driven working machine 1 having an engine 70 that is a diesel engine and a working machine body (not shown) driven by the engine 70, Set the normal range of a predetermined characteristic value of the fuel (ultrasonic propagation speed in the embodiment) as the fuel characteristic reference range of the fuel, and select any one type of fuel selected from light oil and light oil alternative fuels as the fuel to be used in the engine-driven work machine 1. At the same time, store the fuel characteristic reference range (Ymin~Ymax) of the used fuel in the storage means 21 in advance. Acquire the predetermined characteristic value (ultrasonic propagation speed in the embodiment) of the fuel in use detected at any position (fuel tank 80 in the embodiment) of the fuel supply system that supplies fuel to the engine 70 as the fuel characteristic value Y, and perform a fuel characteristic value acquisition process (see S3 in FIG. 3). Compare the fuel characteristic value Y obtained in the fuel characteristic value acquisition process with the fuel characteristic reference range (Ymin~Ymax) of the used fuel stored in the storage means 21, and perform a fuel characteristic value comparison process (see S5 in FIG. 3). As a result of the fuel characteristic value comparison process, when the fuel characteristic value Y is outside the range of the fuel characteristic reference range (Ymin~Ymax) of the used fuel (Y < Ymin or Y > Ymax), it is determined that the fuel is abnormal, and a fuel state determination process (see NO→S9 in S6 of FIG. 3). (Claim 1) It is characterized by including the above.

[0023] The used fuel can be selected from among the selectable fuels consisting of a plurality of types of fuels specified in advance, and the fuel characteristic reference ranges of each fuel constituting the selectable fuels are stored in the storage means 21 in advance. Further include a used fuel setting process (see S2 in FIG. 3) for setting any one type of fuel selected from among the selectable fuels as the used fuel. In the fuel characteristic value comparison process (see S5 in FIG. 3), the fuel characteristic value Y obtained in the fuel characteristic value acquisition process is compared with the fuel characteristic reference range of the fuel set as the used fuel in the used fuel setting process among the fuel characteristic reference ranges of each fuel stored in the storage means 21, and it may be configured to compare it as the fuel characteristic reference range of the used fuel (Claim 2).

[0024] In addition, when the fuel characteristic value described above changes with a change in the fuel temperature X, the storage means 21 stores a correspondence relationship between the change in the fuel temperature and the change in the fuel characteristic reference range, The fuel temperature acquisition process (see S4 in FIG. 3) further includes acquiring a fuel temperature X detected at a position (fuel tank 80 in the embodiment) of a fuel supply system that supplies fuel to the engine 70. In the fuel characteristic value comparison process (see S5 in FIG. 3), it is preferable to compare the fuel characteristic reference range (Ymin to Ymax) corresponding to the fuel temperature X acquired in the fuel temperature acquisition process, among the fuel characteristic reference ranges of the used fuel stored in the storage means 21, with the fuel characteristic value Y acquired in the fuel characteristic value acquisition process (Claim 3).

[0025] In any of the fuel abnormality determination methods described above, it is preferable to further include an operational control process which, when a fuel abnormality is determined in the fuel state determination process (see S9 in Figure 3), reports the determination result ("notifies a warning" in S10 in Figure 3) and / or restricts the start of the engine or performs an emergency stop (S11 in Figure 3) (claims 4 and 5).

[0026] In addition, the fuel abnormality determination device 10 for the engine-driven working machine 1 of the present invention is In a fuel abnormality determination device 10 for an engine-driven working machine 1 having an engine 70 which is a diesel engine and a working machine body (not shown) driven by the engine 70, The fuel used is any one of diesel and diesel alternative fuels selected as the fuel to be used in the engine-driven working machine 1, A storage means 21 in which a normal range of a predetermined characteristic value of a fuel (in an embodiment, the ultrasonic propagation velocity) is set as a fuel characteristic reference range of the fuel, and the fuel characteristic reference range (Ymin to Ymax) of the fuel used is stored in advance; Acquire the predetermined characteristic value (ultrasonic propagation speed in the embodiment) of the fuel in use detected at any position of the fuel supply system that supplies fuel to the engine 70 (fuel tank 80 in the embodiment) as the fuel characteristic value Y, a fuel characteristic value acquisition means 22, Compare the fuel characteristic value Y acquired by the fuel characteristic value acquisition means 22 with the fuel characteristic reference range (Ymin~Ymax) of the fuel in use stored in the storage means 21, a fuel characteristic value comparison means 23, When the fuel characteristic value Y is outside the range of the fuel characteristic reference range (Ymin~Ymax) of the fuel in use (Y < Ymin or Y > Ymax) as a result of the comparison by the fuel characteristic value comparison means 23, determine that the fuel is abnormal, a fuel state determination means 24, characterized by including (claim 6).

[0027] In a configuration where the fuel in use can be selected from among a group of a plurality of types of fuels specified in advance as selectable fuels, the storage means 21 stores in advance the fuel characteristic reference ranges of each fuel constituting the selectable fuels, and Further include a used fuel setting means 25 for setting any one fuel selected from among the selectable fuels as the used fuel, In the fuel characteristic value comparison means 23, compare the fuel characteristic value Y acquired by the fuel characteristic value acquisition means 22 with the fuel characteristic reference range of the fuel set as the used fuel by the used fuel setting means 25 among the fuel characteristic reference ranges of each fuel stored in the storage means 21 as the fuel characteristic reference range (Ymin~Ymax) of the used fuel (claim 7).

[0028] Furthermore, when using a characteristic value of the fuel that changes as the fuel temperature X changes as the characteristic value of the fuel, the storage means 21 stores the correspondence relationship between the change in the fuel characteristic reference range with respect to the change in the fuel temperature X, and Further provide a fuel temperature acquisition means 26 for acquiring the fuel temperature X detected at any position of the fuel supply system that supplies fuel to the engine 70 (fuel tank 80 in the embodiment), The fuel characteristic value comparison means 23 may compare the fuel characteristic reference range (Ymin to Ymax) corresponding to the fuel temperature X acquired by the fuel temperature acquisition means 26, among the fuel characteristic reference ranges of the used fuel stored in the memory means 21, with the fuel characteristic value Y acquired by the fuel characteristic value acquisition means 22 (Claim 8).

[0029] Either of the fuel abnormality determination devices 10 having the above configurations may further include an operation control means 27 which, when a fuel abnormality is determined by the fuel state determination means 24, notifies the determination result and / or restricts starting or performs an emergency stop of the engine 70 (claims 9 and 10). Effect of the Invention

[0030] With the configuration of the present invention as described above, the fuel abnormality determination method and determination device 10 for the engine-driven working machine 1 of the present invention can provide the following significant effects.

[0031] In the present invention, the events to be judged are limited to "fuel abnormality", and fuel abnormality is judged on the assumption that, regardless of the type of fuel actually being supplied to the engine-driven work machine 1, the fuel being supplied to the engine-driven work machine is the "used fuel", which is any one type of fuel selected from diesel or diesel alternative fuel as the fuel to be used in the engine-driven work machine 1.Therefore, it is possible to judge a fuel abnormality by the extremely simple method of determining whether the fuel characteristic value Y of the fuel in the fuel supply system is outside the fuel characteristic standard range (normal range) Ymin to Ymax of the used fuel stored in the memory means 21.

[0032] Furthermore, by determining whether a fuel abnormality exists based on whether the fuel characteristic value Y of the fuel in the fuel supply system is outside the fuel characteristic standard range (normal range) Ymin to Ymax of the fuel used stored in the memory means 21, it is possible to determine a fuel abnormality not only when the fuel characteristic value has changed due to the mixing of different fuels, but also when the fuel characteristic value has changed due to changes in the properties of the fuel over time (deterioration).

[0033] In a configuration in which the above-mentioned fuel to be used can be selected from among a group of pre-specified multiple types of fuel, and the fuel characteristic standard ranges of each fuel constituting the selectable fuels are stored in the memory means 21, and the fuel to be used can be specified from among the selectable fuels by the fuel to be used setting means 25, by comparing the fuel characteristic value Y acquired by the fuel characteristic value acquisition means 22 with the fuel characteristic standard range (Ymin to Ymax) of the fuel type set as the fuel to be used by the fuel to be used setting means 25 among the fuel characteristic standard ranges of each fuel stored in the memory means 21, it is possible to easily determine a fuel abnormality even when the type of fuel to be used in the engine-driven working machine 1 can be set arbitrarily.

[0034] When determining whether a fuel abnormality exists based on a characteristic value that changes with a change in fuel temperature X, the correspondence relationship of the change in the fuel characteristic reference range to the change in fuel temperature X is stored in advance in the storage means 21, the fuel temperature X is detected and acquired, and the fuel abnormality is determined using the fuel characteristic reference range Ymin to Ymax that corresponds to the acquired fuel temperature X, making it possible to accurately determine a fuel abnormality even if the fuel characteristic value changes with a change in fuel temperature X.

[0035] In addition, in a configuration provided with an operation control means 27 that notifies the operator of the result of a fuel abnormality when it is determined that there is a fuel abnormality and / or restricts or stops the engine from starting in an emergency, the occurrence of a fuel abnormality can be easily notified to the operator, and / or by restricting or stopping the engine from starting, it is possible to prevent the illegal consumption of illegal diesel fuel and breakdowns of the engine 70 due to the use of degraded fuel. [Brief description of the drawings]

[0036] [Figure 1] FIG. 2 is a functional block diagram of a fuel abnormality determination device for an engine-driven working machine according to the present invention. [Diagram 2]FIG. 2 is an explanatory diagram of the fuel characteristic reference range to be stored in the storage means (a correlation diagram of the fuel temperature-fuel characteristic reference range for each selected fuel (diesel, GTL fuel, B100)). [Diagram 3] 2 is a flow chart showing the operation of the fuel abnormality determination device of FIG. 1; DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0037] Hereinafter, a fuel abnormality determination device 10 for an engine-driven working machine according to the present invention will be described with reference to the accompanying drawings.

[0038] [Target engine-driven working machines] The fuel abnormality determination device 10 of the present invention can be installed in various types of engine-driven work machines 1, without any particular limitation, so long as the engine-driven work machine 1 has an engine 70, which is a diesel engine, and a work machine main body (not shown) driven by the engine 70.Examples of engine-driven work machines 1 that are equipped with the fuel abnormality determination device 10 of the present invention include engine-driven generators, engine-driven compressors, engine-driven pumps, etc.

[0039] In this embodiment, it is planned that the "fuel used" which is the fuel used in the engine-driven work machine 1 will be set by the operator to any type selected from the "selectable fuels" consisting of the group of diesel, GTL fuel, and B100 fuel; however, the types of selectable fuels are not limited to the above examples, and it may be possible to select from a greater or lesser number of selectable fuels, and the above-mentioned selectable fuels may also include B5 diesel, which is commonly used as an alternative fuel to diesel in the construction industry.

[0040] In addition, the fuel abnormality determination device 10 of the present invention may be installed in an engine-driven work machine 1 in which the aforementioned "fuel used", which is the fuel used in the engine-driven work machine 1, is limited to only one type, for example, at the stage of shipping the engine-driven work machine 1 from a factory.

[0041] [Fuel abnormality determination device] FIG. 1 shows an example of the configuration of a fuel abnormality determination device 10 for an engine-driven working machine 1 according to the present invention.

[0042] As shown in FIG. 1, the fuel abnormality determination device 10 of this embodiment is equipped with an electronic control device (control device 20) such as a microcontroller, detection means such as a fuel characteristic value detection means 31 and a temperature detection means 32, input means such as a fuel usage input means 41, and notification means such as a warning display means 51 and an alarm 52 consisting of a monitor screen or the like for notifying an operator of a fuel abnormality, as well as a memory means 21, a fuel usage setting means 25, a fuel characteristic value acquisition means 22, a fuel temperature acquisition means 26, a fuel characteristic value comparison means 23, a fuel state determination means 24, an operation control means 27, etc., which are realized in the control device 20 mentioned above.

[0043] (1) Storage means The memory means 21 stores, as a fuel characteristic standard range, standard values ​​(range of normal values) required to determine whether or not an abnormality has occurred in the fuel based on the characteristic values ​​of the fuel in use detected by the fuel characteristic value detection means 31 described later.

[0044] In the configuration of this embodiment, an ultrasonic sensor is provided as the fuel characteristic value detection means 31, and the ultrasonic propagation velocity of the fuel detected by this ultrasonic sensor is acquired as the fuel characteristic value Y by the fuel characteristic value acquisition means 22 described below.The normal range of values ​​of the ultrasonic propagation velocity of the fuel used is stored in the memory means 21 as the above-mentioned fuel characteristic standard range (Ymin to Ymax).

[0045] When the fuel (used fuel) used in the engine-driven work machine 1 is limited in advance to only one type of fuel, it is possible to store only the fuel characteristic standard range (Ymin~Ymax) of that one type of fuel. However, in the configuration of the determination device 10 of this embodiment, which allows any one type of fuel selected from the group of selectable fuels consisting of diesel, GTL fuel, and B100 fuel to be set as the used fuel, the fuel characteristic standard range (Ymin~Ymax) of each fuel (diesel, GTL fuel, and B100 fuel) that constitutes the selectable fuels is stored in the memory means 21 as shown in Figure 2.

[0046] In addition, in this embodiment, the ultrasonic propagation velocity, which causes a change in the characteristic value of the fuel in accordance with a change in the fuel temperature X, is adopted as the characteristic value of the fuel, and the corresponding relationship of the change in the fuel characteristic reference range to the change in the fuel temperature X is also stored in advance in the storage means, as shown in FIG. 2.

[0047] However, when the characteristic values ​​of the fuel used in the comparison are those whose characteristic values ​​do not change with changes in fuel temperature X, there is no need to store in the memory means the changes in the fuel characteristic reference range in response to changes in fuel temperature X.

[0048] In addition, in this embodiment, an example is given in which ultrasonic propagation speed is used as the characteristic value of the fuel used in the comparison; however, the characteristic value of the fuel used in the comparison is not limited to ultrasonic propagation speed, and various characteristic values ​​such as the electrostatic capacitance and thermal conductivity of the fuel can be used, and a combination of two or more of these may also be used.

[0049] In this case, two or more types of fuel characteristic reference ranges are stored in the storage means 21 in accordance with the characteristic values ​​to be used in combination.

[0050] (2)Use fuel setting means The fuel to be used setting means 25 executes a fuel to be used setting process, in which the operator uses a fuel to be used input means 41, such as a touch panel provided on the engine-driven work machine, to select and input one of the above-mentioned selectable fuels (in this embodiment, diesel, GTL fuel, and B100 fuel) as the above-mentioned "fuel to be used" to be used by the engine-driven work machine 1. If the fuel to be used (fuel to be used) by the engine-driven work machine 1 is limited to one type in advance, the fuel to be used setting means 25 and the above-mentioned fuel to be used input means 41 do not need to be provided.

[0051] In this embodiment in which diesel, GTL fuel, and B100 fuel are set as the aforementioned selectable fuels, when the operator selects the type of oil by touching one of the displays "diesel," "GTL," or "B100" (as an example, "diesel") displayed on the touch panel which is the aforementioned fuel use input means 41, the fuel use setting means 25 which receives a signal from the fuel use input means (touch panel) 41 sets the type of oil as the fuel to be used by temporarily storing the selection result made by the operator on the touch panel 41 (as an example, the selection of diesel).

[0052] When changing the fuel to be used, the operator selects a new oil type (e.g., B100) from the oil types displayed on the fuel to be used input means (touch panel) 41, and the fuel to be used setting means 25 updates the temporarily stored selection result of the oil type (light oil as an example) to the newly selected oil type (B100 as an example), thereby changing the specified oil type.

[0053] (3) Means for acquiring fuel characteristic values The fuel characteristic value acquisition means 22 executes a fuel characteristic value acquisition process in which it receives the fuel characteristic value of the fuel in use detected by a fuel characteristic value detection means 31 provided at any position in the fuel supply system, and acquires this as a fuel characteristic value Y.

[0054] In the embodiment shown in FIG. 1, an ultrasonic sensor is provided as a fuel characteristic value detection means 31 in a fuel tank 80 constituting a fuel supply system, and the ultrasonic propagation speed of the fuel detected by the ultrasonic sensor 31 can be acquired by a fuel characteristic value acquisition means 22 as a fuel characteristic value Y.

[0055] However, as mentioned above, a capacitance sensor or a thermal conductivity sensor may be provided as the fuel characteristic value detection means 31 to detect the capacitance and thermal conductivity of the fuel, and the capacitance and thermal conductivity detected in this manner may be acquired by the fuel characteristic value acquisition means 22 as the fuel characteristic value Y. Furthermore, the fuel characteristic value Y to be acquired may be not only one of the above-mentioned values, but also a combination of multiple types.

[0056] (4) Fuel temperature acquisition means The fuel temperature acquisition means 26 executes a fuel temperature acquisition process to acquire the fuel temperature X by receiving a detection signal of the fuel temperature X in the fuel supply system detected by a fuel temperature detection means 32 provided at any position in the fuel supply system that supplies fuel to the engine 70.

[0057] The fuel temperature detection means 32 may be provided at any position in the fuel supply system, but is preferably provided at the same position as the fuel characteristic value detection means 31 described above, thereby making it possible to obtain the characteristic value and fuel temperature X of the fuel at the same position.

[0058] In this embodiment, together with the ultrasonic sensor which is the above-mentioned fuel characteristic value detection means 31, a temperature sensor is provided as the above-mentioned fuel temperature detection means 32 at a common position in the fuel tank 80, so that the fuel temperature X in the fuel tank 80 can be detected and the fuel temperature X detected by the temperature sensor 32 can be acquired by the above-mentioned fuel temperature acquisition means 26 as the fuel temperature X.

[0059] Incidentally, the fuel temperature acquisition means 26 and the fuel temperature detection means 32 are components that are necessary when a characteristic value that changes with a change in fuel temperature X is adopted as the aforementioned fuel characteristic value, and do not need to be provided when a fuel abnormality is determined using a characteristic value that does not change with a change in fuel temperature X.

[0060] (5) Fuel characteristic value comparison means The fuel characteristic value comparison means 23 executes a fuel characteristic value comparison process to compare the fuel characteristic value Y acquired by the above-mentioned fuel characteristic value acquisition means 22 with the fuel characteristic reference range (Ymin to Ymax) of the fuel used stored in the memory means 21.

[0061] In this embodiment, one type of fuel selected from a group of selectable fuels consisting of diesel, GTL fuel, and B100 fuel is set as the fuel to be used in the engine-driven working machine 1, and the ultrasonic propagation velocity that changes with a change in fuel temperature X is adopted as the fuel characteristic value to be used in comparison. The fuel characteristic value comparison means 23 calculates a fuel characteristic reference range Ymin-Ymax at the detected fuel temperature X for the oil type set as the fuel to be used, based on the setting result of the fuel to be used set by the fuel to be used setting means 25, the fuel temperature X acquired by the fuel temperature acquisition means 26, and the correlation between the fuel temperature and the fuel characteristic reference range of the selectable fuel stored in the storage means 21 (see FIG. 2), and compares the calculated fuel characteristic reference range Ymin-Ymax with the fuel characteristic value Y acquired by the fuel characteristic value acquisition means 22.

[0062] For example, when the type of oil set as the fuel to be used by the fuel to be used setting means 25 is B100 fuel and the fuel temperature X acquired by the fuel temperature acquisition means 26 is 30°C, the fuel characteristic value comparison means 23 calculates a fuel characteristic standard range (see FIG. 2) consisting of a lower limit value indicated by Ymin (B100 / 30°C) and an upper limit value indicated by Ymax (B100 / 30°C) based on the correlation between the fuel temperature and fuel characteristic standard range of the selected fuel stored in the storage means 21, and compares it with the fuel characteristic value Y acquired by the fuel characteristic value acquisition means 22.

[0063] (6) Fuel state determination means When the fuel characteristic value Y acquired by the fuel characteristic value acquisition means 22 is outside the range of the fuel characteristic reference range [Ymin to Ymax: Ymin (B100 / 30°C) to Ymax (B100 / 30°C) in the previous example] (Y < Ymin or Y > Ymax) as a result of the comparison by the fuel characteristic value comparison means 23, the fuel state determination means 24 determines that there is a fuel abnormality and executes a fuel state determination process.

[0064] (7) Operation control means When a fuel abnormality is determined by the fuel state determination means 24, the operation control means 27 executes an operation control process to control the operations of each part of the engine-driven work machine 1 accordingly.

[0065] Specifically, when a fuel abnormality is determined, notification processes such as lighting of a warning lamp, warning display by a warning display means 51 such as a monitor screen, and sounding of a warning sound by an alarm 52, output of a control signal to an engine control unit (ECU) 71, etc. are performed. When the engine 70 is stopped, a start restriction that makes it impossible to start the engine 70, or when the engine 70 is operating, an emergency stop that stops the engine 70, etc. are performed by combining any one or a plurality of engine operation control processes. In this embodiment, it is configured to perform all of the above processes.

[0066] (8) Others (Fuel type determination means) As described above, in the configuration of the fuel abnormality determination device 10 of the engine-driven work machine 1 of this embodiment, in which any one type of fuel selected from the selectable fuels preset by the used fuel setting means 25 can be set as the used fuel, in addition to the above-described means, a fuel type determination means 28 may be further provided.

[0067] This fuel type determination means 28 executes a fuel type determination process in which it compares the fuel characteristic value Y acquired by the fuel characteristic value acquisition means 22 with the fuel characteristic reference range Ymin to Ymax of each fuel constituting the selected fuel, which is stored in the memory means, and determines that an oil type that includes the fuel characteristic value Y acquired by the fuel characteristic value acquisition means 22 within the fuel characteristic reference range Ymin to Ymax is the fuel in use.

[0068] In the configuration of the present embodiment in which the determination is made using the ultrasonic propagation velocity, whose characteristic value changes with a change in fuel temperature X, as the fuel characteristic value, the fuel type determination means 28 calculates the fuel characteristic reference range (normal range) Ymin to Ymax of each selection target fuel at the fuel temperature X acquired by the fuel temperature acquisition means 26 based on the fuel temperature X acquired by the fuel temperature acquisition means 26 and the correlation between the fuel temperature and the fuel characteristic reference range of the selection target fuel stored in the storage means 21 (see FIG. 2 ), and compares the calculated fuel characteristic reference range with the fuel characteristic value Y acquired by the fuel characteristic value acquisition means.

[0069] The fuel type determination means 28 may further display the determination result on a monitor screen or the like, which is a determination result display means 55.

[0070] In this way, by providing the fuel type determination means 28, even if the type of fuel currently being used in the engine-driven work machine 1 becomes unknown because, for example, the type of fuel being used was not communicated when the operator was changed, the operator can predict the fuel currently being used based on the determination result of the fuel type determination means 28.

[0071] However, in order for the fuel type determination means 28 to make an accurate determination, it is necessary that the fuel stored in the fuel tank of the engine-driven work machine 1 does not have any abnormalities such as mixing of different fuels or deterioration over time.If the fuel characteristic values ​​have changed due to such fuel abnormalities (mixing of multiple oil types or deterioration over time), it may not be possible to accurately determine the fuel type.

[0072] (9) Operation, etc. The operation of the fuel abnormality determination device 10 for the engine-driven working machine 1 of the present invention described above with reference to FIG. 1 will now be described with reference to FIG.

[0073] When the control power supply (ACC power supply) is turned ON (S1) by operating a key switch (not shown) provided on the engine-driven work machine 1, power supply to the electrical equipment (including the control device 20) provided on the engine-driven work machine 1 begins.

[0074] In this state, when the operator selects the type of oil on the fuel to be used input means 41, such as a touch panel provided on the engine-driven work machine 1, the selection made by the operator is temporarily stored and the selected type of oil is set as the fuel to be used in the fuel to be used setting means 25 (S2).

[0075] In addition, when the control power is turned ON, the fuel characteristic value detection means (ultrasonic sensor) 31 begins detecting the characteristic value (ultrasonic propagation velocity) of the fuel in the fuel supply system (fuel tank 80), and the detected fuel characteristic value (ultrasonic propagation velocity of the fuel) is acquired by the fuel characteristic value acquisition means 22 as the fuel characteristic value Y (S3).

[0076] Furthermore, the fuel temperature detection means (temperature sensor) 32 detects the fuel temperature X in the fuel supply system (fuel tank 80), and the detected fuel temperature X is acquired as the fuel temperature X by the fuel temperature acquisition means 26 (S4).

[0077] In this manner, once the fuel characteristic value Y has been acquired by the fuel characteristic value acquisition means 22 and the fuel temperature X has been acquired by the fuel temperature acquisition means 26, the fuel characteristic value comparison means 23 is activated and compares the fuel characteristic value Y acquired by the fuel characteristic value acquisition means 22 with the fuel characteristic reference range (Ymin to Ymax) stored in the memory means 11 (S5).

[0078] The comparison of the fuel characteristic values in the fuel characteristic value comparison means 23 is performed by calculating the fuel characteristic reference range Ymin to Ymax at the acquired fuel temperature X of the oil type set as the fuel in use based on the correlation between the fuel temperature - fuel characteristic reference range of the fuel to be selected stored in the storage means 21 (see Fig. 2), and comparing the calculated fuel characteristic reference range Ymin to Ymax with the fuel characteristic value Y acquired by the fuel characteristic value acquisition means 22.

[0079] As an example, when the oil type set by the fuel setting means 25 for use is B100 fuel and the fuel temperature X acquired by the fuel temperature acquisition means is 30°C, the fuel characteristic value comparison means 23 calculates a fuel characteristic reference range with Ymin(B100 / 30°C) as the lower limit value and Ymax(B100 / 30°C) as the upper limit value and compares it with the fuel characteristic value Y acquired by the fuel characteristic value acquisition means 22 (S5).

[0080] In this way, based on the comparison by the fuel characteristic value comparison means 23, when the fuel characteristic value Y acquired by the fuel characteristic value acquisition means 22 is within the range of the aforementioned fuel characteristic reference range (Ymin ≤ Y ≤ Ymax) (YES in S6), the fuel state determination means 24 determines that the fuel is in a normal state (S7), and the engine-driven work machine can operate normally (S8).

[0081] On the other hand, when the fuel characteristic value Y acquired by the fuel characteristic value acquisition means 22 is outside the range of the aforementioned fuel characteristic reference range (Y < Ymin or Y > Ymax) (NO in S6), the fuel state determination means 24 determines that there is a fuel abnormality (S9), and the operation control means 27 performs an alarm notification such as a warning display by the warning display means 51 and a warning sound by the alarm 52 (S10). When the engine has not been started, a start restriction is imposed to make the engine start impossible, and when the engine is operating, the engine is stopped urgently (S11). Thereby, the consumption of improper fuel and the use of deteriorated fuel are prevented, and this operation continues until the control power supply is turned off (S12).

Explanation of Signs

[0082] 1 Engine-driven work machine 10 Fuel abnormality determination device 20 Control device 21 Memory means 22 Fuel characteristic value acquisition means 23 Fuel characteristic value comparison means 24 Fuel state determination means 25 Fuel setting means 26 Fuel temperature acquisition means 27 Operation Control Means 28 Fuel type determination means 31 Fuel characteristic value detection means (ultrasonic sensor) 32 Fuel temperature detection means (temperature sensor) 41 Fuel usage input means (touch panel) 51 Warning display means 52 Alarm 55 Judgment result display means (monitor screen) 70 Engine 71 Engine Control Unit (ECU) 80 Fuel Tank

Claims

1. A method for determining a fuel abnormality in an engine-driven working machine having a diesel engine and a working machine body driven by the engine, comprising: A normal range of a predetermined characteristic value of a fuel is defined as a fuel characteristic reference range of the fuel, and any one type of fuel selected from diesel and diesel alternative fuels as a fuel to be used in the engine-driven working machine is defined as a used fuel, and the fuel characteristic reference range of the used fuel is stored in advance in a storage means, a fuel characteristic value acquisition process for acquiring, as a fuel characteristic value, the predetermined characteristic value of the fuel being used detected at any position in a fuel supply system that supplies fuel to the engine; a fuel characteristic value comparison process for comparing the fuel characteristic value acquired in the fuel characteristic value acquisition process with the fuel characteristic reference range of the used fuel stored in the storage means; a fuel state determination process for determining that a fuel abnormality exists when the fuel characteristic value is outside the fuel characteristic reference range of the used fuel as a result of the fuel characteristic value comparison process; A method for determining a fuel abnormality in an engine-driven working machine, comprising:

2. The fuel to be used is selectable from a selection target fuel consisting of a group of a plurality of types of fuels designated in advance, and the fuel characteristic reference range of each of the fuels constituting the selection target fuel is stored in advance in the storage means, The method further includes a fuel use setting process for setting one of the fuels selected from the selection target fuels as the fuel use, In the fuel characteristic value comparison process, the fuel characteristic value acquired in the fuel characteristic value acquisition process is compared with the fuel characteristic reference range of the fuel set as the used fuel in the used fuel setting process among the fuel characteristic reference ranges of each of the fuels stored in the storage means as the fuel characteristic reference range of the used fuel.

2. The method for determining a fuel abnormality in an engine-driven working machine according to claim 1.

3. A correspondence relationship between a change in the fuel temperature and a change in the fuel characteristic reference range is stored in the storage means, A fuel temperature acquisition process for acquiring a fuel temperature detected at any position in a fuel supply system that supplies fuel to the engine, 3. A fuel abnormality determination method for an engine-driven working machine as described in claim 1 or 2, characterized in that in the fuel characteristic value comparison process, the fuel characteristic reference range of the used fuel corresponding to the fuel temperature acquired in the fuel temperature acquisition process, among the fuel characteristic reference ranges of the used fuel stored in the memory means, is compared with the fuel characteristic value acquired in the fuel characteristic value acquisition process.

4. The method for determining a fuel abnormality in an engine-driven working machine as described in claim 1 or 2, further comprising an operational control process for notifying the result of the determination and / or restricting the start of the engine or performing an emergency stop when a fuel abnormality is determined in the fuel state determination process.

5. The method for determining a fuel abnormality in an engine-driven working machine as described in claim 3, further comprising an operational control process for notifying the result of the determination and / or restricting the start of the engine or performing an emergency stop when a fuel abnormality is determined in the fuel state determination process.

6. A fuel abnormality determination device for an engine-driven working machine having a diesel engine and a working machine body driven by the engine, The fuel used is any one of diesel and diesel alternative fuels selected as the fuel to be used in the engine-driven working machine, a storage means for storing in advance a fuel characteristic reference range for the fuel used, the fuel characteristic reference range being a normal range of a predetermined characteristic value of the fuel; a fuel characteristic value acquisition means for acquiring, as a fuel characteristic value, the predetermined characteristic value of the fuel being used detected at any position in a fuel supply system that supplies fuel to the engine; a fuel characteristic value comparison means for comparing the fuel characteristic value acquired by the fuel characteristic value acquisition means with the fuel characteristic reference range of the used fuel stored in the storage means; a fuel state determination means for determining that a fuel abnormality exists when the fuel characteristic value is outside the fuel characteristic reference range of the used fuel as a result of comparison by the fuel characteristic value comparison means; A fuel abnormality determination device for an engine-driven working machine, comprising:

7. The fuel to be used is selectable from a selection target fuel consisting of a group of a plurality of types of fuels designated in advance, and the fuel characteristic group ranges of each of the selection target fuels are stored in advance in the storage means, The method further includes a fuel use setting means for setting one type of fuel selected from the selection target fuels as the fuel use, The fuel characteristic value comparison means compares the fuel characteristic value acquired by the fuel characteristic value acquisition means with the fuel characteristic reference range of the fuel set as the used fuel by the used fuel setting means among the fuel characteristic reference ranges of each of the fuels stored in the storage means as the fuel characteristic reference range of the used fuel.

7. The fuel abnormality determination device for an engine-driven working machine according to claim 6.

8. The storage means stores a correspondence relationship between a change in the fuel characteristic reference range and a change in the fuel temperature, a fuel temperature acquisition means for acquiring a fuel temperature detected at a position in a fuel supply system for supplying fuel to the engine; A fuel abnormality determination device for an engine-driven working machine as described in claim 6 or 7, characterized in that the fuel characteristic value comparison means compares the fuel characteristic reference range of the used fuel corresponding to the fuel temperature acquired by the fuel temperature acquisition means, among the fuel characteristic reference ranges of the used fuel stored in the memory means, with the fuel characteristic value acquired by the fuel characteristic value acquisition means.

9. 8. A fuel abnormality determination device for an engine-driven working machine as described in claim 6 or 7, further comprising an operation control means for, when a fuel abnormality is determined by the fuel state determination means, notifying the determination result and / or restricting the start of the engine or performing an emergency stop.

10. 9. A fuel abnormality determination device for an engine-driven working machine as described in claim 8, further comprising an operation control means for, when a fuel abnormality is determined by the fuel state determination means, notifying the determination result and / or restricting the start of the engine or performing an emergency stop.

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