Fuel property diagnosis device, vehicle and fuel property diagnosis method

Abstract

To provide a fuel property diagnosis device, a vehicle and a fuel property diagnosis method capable of specifying fuel properties.SOLUTION: A vehicle comprises: a storage unit that is connected to a fuel tank for storing fuel to be supplied to an internal combustion engine, and heats the fuel; and a specification unit that specifies fuel properties of the fuel based on a pressure in the storage unit at a predetermined detection temperature.SELECTED DRAWING: Figure 2

Description

[Technical Field]

[0001] The present invention relates to a fuel property diagnostic device, a vehicle, and a fuel property diagnostic method. [Background technology]

[0002] In vehicles such as trucks, the properties of fuel stored in the fuel tank of the internal combustion engine are often determined. For example, there are methods for determining the difference between diesel and other fuels by utilizing the chemical structure of the compounds that make up the fuel and the absorption of light. To improve the accuracy of diesel fuel determination, the wavelength of the light source used for the determination is one that is strongly absorbed by diesel. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Laid-Open No. 2015-138019 Summary of the Invention [Problem to be solved by the invention]

[0004] In recent years, the development of carbon-neutral fuels has progressed, with a movement toward carbon-neutralization, which reduces CO2 emissions from internal combustion engines. However, carbon-neutral fuels are produced by synthetic methods and have a wide variety of chemical structures, making it difficult to identify fuels based on specific wavelengths. For this reason, there is a demand for technology to determine the properties of various fuels, including synthetic fuels.

[0005] An object of the present invention is to provide a fuel property diagnostic device, a vehicle, and a fuel property diagnostic method that can identify the fuel property. [Means for solving the problem]

[0006] In one embodiment, a vehicle is provided with a storage unit connected to a fuel tank that stores fuel to be supplied to an internal combustion engine, and that heats the fuel, and an identification unit that identifies the fuel properties of the fuel based on the pressure within the storage unit at a predetermined detection temperature. [Effects of the Invention]

[0007] According to the present invention, it is possible to provide a fuel property diagnostic device, a vehicle, and a fuel property diagnostic method that are capable of identifying fuel properties. [Brief explanation of the drawings]

[0008] [Figure 1] 1 is an explanatory diagram showing a schematic configuration of a vehicle according to an embodiment of the present invention; [Figure 2] FIG. 1 is a block diagram showing a schematic configuration of a portion of a vehicle. [Figure 3] 4 is a graph showing an example of the relationship between fuel heating time and pressure. [Figure 4] 4 is a flowchart of a fuel property diagnosis process according to the embodiment; DETAILED DESCRIPTION OF THE INVENTION

[0009] A vehicle 10 according to one embodiment of the present invention will be described below with reference to Figures 1 to 4. Figure 1 is an explanatory diagram showing the general configuration of the vehicle, and Figure 2 is a block diagram showing the general configuration of a fuel property diagnosis device in part of the vehicle 10. Figure 3 is a graph showing an example of the relationship between fuel heating time and pressure, and Figure 4 is a flowchart of fuel property diagnosis processing. Note that in each figure, the configuration is enlarged, reduced, or omitted as appropriate for ease of explanation.

[0010] As shown in FIG. 1, a vehicle 10 includes an internal combustion engine 12, a fuel tank 13, a vapor pressure detection unit 14 (detection unit), a driving unit 16, and a control unit 17. When the piston of the internal combustion engine 12 of the vehicle 10 is driven, driving force is transmitted to the wheels of the driving unit 16. In this embodiment, the vapor pressure detection unit 14 and the control unit 17 constitute a fuel property diagnosis device (identification unit) 20. In this embodiment, the fuel property diagnosis device 20 determines, as fuel properties, whether a compliant fuel is genuine or non-compliant fuel, which has a different volatility at a predetermined temperature from that of genuine fuel. For example, carbon-neutral synthetic fuel is defined as genuine fuel, and diesel contained in the fuel under test is defined as non-compliant fuel, and the fuel property is determined to determine whether the fuel under test is genuine or non-compliant.

[0011] The internal combustion engine 12 is an engine such as a diesel engine or a gasoline engine. The internal combustion engine 12 is, for example, a multi-cylinder engine having multiple cylinders. The internal combustion engine 12 has a fuel injection valve and is connected to a fuel tank 13. The internal combustion engine 12 is supplied with fuel from the fuel tank 13, and operates to generate power (torque) that serves as driving force. The internal combustion engine 12 is connected to a running unit 16 and drives the running unit 16. The opening and closing of the fuel injection valve of each cylinder of the internal combustion engine 12, as well as the amount and timing of fuel supply, are configured to be controllable by a control unit 17.

[0012] For example, the internal combustion engine 12 includes an engine body, an intake passage, an exhaust passage, and a fuel injection device. For example, the engine body includes a cylinder head, a cylinder block, a crankcase, and pistons, a crankshaft, valves, etc. housed therein.

[0013] The fuel tank 13 includes a tank portion 131, an open / close cap 132 (open / close lid), and a fuel supply passage 133.

[0014] The tank portion 131 stores fuel. The tank portion 131 is connected to the internal combustion engine 12 and supplies a predetermined amount of fuel to the internal combustion engine 12. The tank portion 131 has a supply port 131a which is an opening through which the fuel is supplied. An opening / closing cap 132 is provided on the supply port 131a of the tank portion 131.

[0015] The opening / closing cap 132 is a lid member that opens and closes the supply port 131a of the tank part 131. The opening / closing cap 132 is provided with a cap sensor 132a, which is configured to be able to detect the opening and closing of the opening / closing cap 132, for example, the opening / closing operation or the presence or absence of the opening / closing cap 132.

[0016] The fuel supply path 133 is a flow path that connects the lower part of the tank part 131 and the internal combustion engine 12. The fuel supply path 133 is provided with a valve 133a that opens and closes the flow path under the control of the control part 17.

[0017] The vapor pressure detection unit 14 includes a heating pipe 141 as a container, a fuel passage 142, a pump 143, a heater 141b, a pressure gauge 145 as a pressure detection unit, and a plurality of valves 146-148.

[0018] Heating pipe 141 includes a storage section 141a that stores fuel supplied from tank section 131, and a heater 141b provided in storage section 141a. Heating pipe 141 heats storage section 141a with heater 141b, thereby heating the fuel stored inside to a predetermined temperature. For example, heating pipe 141 is configured so that storage section 141a can be opened and closed by control section 17.

[0019] The heater 141b is provided in the heating pipe 141 and heats the heating pipe 141 to a predetermined temperature. For example, the heating temperature and heating timing of the heater 141b are controlled by the control unit 17.

[0020] The fuel passage 142 connects the tank portion 131 of the fuel tank 13 and the heating pipe 141. For example, the fuel passage 142 includes a first passage 142a connecting the tank portion 131 and the upper portion of the heating pipe 141, a second passage 142b connecting the upper portion of the heating pipe 141 and the tank portion 131, and a third passage 142c connecting the lower portion of the heating pipe 141 and the tank portion 131. The first passage 142a constitutes a supply-side flow path that sends fuel from the tank portion 131 to the heating pipe 141. For example, the second passage 142b has both ends connected to the upper portion of the heating pipe 141 and the fuel tank 13, respectively, and constitutes a recovery flow path for vapor that returns fluid from the upper portion of the heating pipe 141 to the fuel tank 13. The second passage 142b is a pipe that returns gas in the heating pipe 141 to the tank portion 131 so as to prevent the internal pressure of the heating pipe 141 from increasing when fuel is supplied to the heating pipe 141. The third passage 142c has both ends connected to the lower part of the heating pipe 141 and the fuel tank 13, respectively, and forms a fuel recovery flow path that returns the fluid from the lower part of the heating pipe 141 to the fuel tank.

[0021] The pressure gauge 145 is a pressure sensor that is disposed in the upper part of the accommodation part 141a of the heating pipe 141 and detects the pressure at the upper part of the heating pipe 141. The pressure gauge 145 detects the pressure inside the heating pipe 141 due to steam and outputs the detection result. The pressure gauge 145 is connected to the control part 17 and sends the detection result to the control part 17.

[0022] Valves 146 to 148 are provided in first passage 142a, which is a supply flow path, and second passage 142b and third passage 142c, which are recovery flow paths. Valves 146 to 148 are connected to control unit 17, and are opened and closed under the control of control unit 17, thereby opening and closing each of passages 142a, 142b, and 142c.

[0023] The running unit 16 includes a drive shaft, an automatic transmission, a power transmission device, wheels, etc. For example, an automatic transmission is detachably connected to the output shaft of the internal combustion engine 12, and left and right front and rear wheels, which are drive wheels, are connected to the output shaft of the automatic transmission via a power transmission device including a propeller shaft, a differential gear, a transfer, etc. The running unit 16 changes the speed of the transmitted power generated by the rotation of the internal combustion engine 12 at a predetermined gear ratio using the automatic transmission, and transmits it to the front and rear wheels via the power transmission device.

[0024] The control unit 17 is a device that performs calculations such as a computer, and includes various processing circuits such as an input / output device, a storage device (ROM, RAM, non-volatile RAM, etc.), and a central processing unit (CPU). The control unit 17 executes various programs to function as a driving control device or a fuel property diagnosis device (identification unit). The control unit 17 may be provided in the vehicle 10, or a part or all of the control unit 17 may be provided in another external terminal. For example, the control unit 17 that functions as the fuel property diagnosis device may be part of an ECU that controls the internal combustion engine 12. Furthermore, the control unit 17 that functions as the fuel property diagnosis device (identification unit) may be provided in a terminal other than the vehicle 10.

[0025] Various sensors are connected to the control unit 17, and detection and operation information from these devices is input to the control unit 17. The control unit 17 is also connected to the internal combustion engine 12, and controls the operation of each of these units.

[0026] For example, the control unit 17 controls the driving of the vehicle 10 based on operation information such as accelerator operation information of the vehicle 10 and various detection values. That is, the control unit 17 transmits control signals to each unit to perform control processes necessary for various operations, such as controlling the operation of the internal combustion engine 12. For example, the control unit 17 controls the torque and rotation speed generated by the internal combustion engine 12 by controlling the fuel injection amount of the internal combustion engine 12. Furthermore, the control unit 17 performs a fuel property diagnosis process (identification process) as part of the control process. For example, as an example of the fuel property diagnosis process, carbon-neutral synthetic fuel is determined to be a compliant fuel, and diesel contained in the fuel being tested is detected as a non-compliant fuel.

[0027] As part of the fuel property diagnostic process, the control unit 17 determines the difference in composition between, for example, diesel refined from crude oil and carbon-neutral synthetic fuel based on the difference in their vapor pressures. Figure 3 is a graph showing the signal intensity results of evaporated components over time when diesel is heated at a constant temperature, showing the distribution of the amount of evaporation by temperature when the diesel is heated. In Figure 3, the horizontal axis represents time, and the vertical axis represents the intensity of the detected signal. For example, the horizontal axis represents the heating time, which corresponds to the temperature.

[0028] As shown in Figure 3, diesel fuel contains components that volatilize over a wide temperature range, from low to high. Figure 3 shows that the evaporation of components contained in the target fuel is detected over a wide temperature range, for example, from 50 to 200°C. Carbon-neutral fuel, on the other hand, is primarily composed of a specific composition, and the temperature range over which the components contained in carbon-neutral fuel evaporate may be narrower than the temperature range over which the primary components of diesel evaporate. Therefore, the detection temperature is set to the range where the vapor pressure differs depending on the composition. The fuel in the fuel tank is heated to the specified detection temperature using a heating tube, and the vapor pressure is measured to distinguish between genuine and non-genuine fuel components as a fuel property.

[0029] The fuel property diagnosis method according to this embodiment will be described below with reference to the flowchart of Fig. 4. The fuel property diagnosis method according to this embodiment includes feeding fuel in the fuel tank 13 to the heating pipe 141 and heating it to a predetermined detection temperature, detecting the pressure in the heating pipe 141, and identifying the fuel property based on the pressure value in the heating pipe 141 at the detection temperature.

[0030] First, in step ST1, the control unit 17 determines whether or not a start condition for the fuel property diagnosis process is satisfied. For example, in this embodiment, the start condition is detected as the supply of fuel to the fuel tank 13. As an example, the control unit 17 determines that the start condition is satisfied when the opening / closing cap 132 of the fuel tank 13 is opened or closed. For example, the control unit 17 determines that the start condition is satisfied when the opening / closing cap 132 is opened and then closed, or when the opening / closing cap 132 is still open. The control unit 17 detects the opening / closing of the opening / closing cap 132 of the fuel tank 13 using the cap sensor 132a, and if it determines that the start condition is satisfied (Yes in step ST1), the process proceeds to step ST2. If it determines that the start condition is not satisfied (No in step ST1), the control unit 17 continues monitoring until the start condition is satisfied.

[0031] In step ST2, the control unit 17 sends the fuel in the tank unit 131 to the accommodation unit 141a of the heating pipe 141. Specifically, the control unit 17 opens the valves 146 and 147 to open the first passage 142a and the second passage 142b, and closes the recovery side valve 148, thereby supplying the fuel in the fuel tank to the heating pipe 141 (step ST2).

[0032] Then, when it is detected that the amount of fuel supplied to the heating pipe 141 has reached a predetermined specified amount (step ST3), the valves 146 and 147 are closed to terminate the supply of fuel to the heating pipe 141 (step ST4).

[0033] Furthermore, in step ST5, the control unit 17 activates the heater 141b to heat the fuel in the heating tube 141 to a predetermined temperature. The heating temperature at this time is a predetermined detection temperature that is set based on the component to be identified. For example, the detection temperature is set to a predetermined temperature that is within a temperature range in which there is a difference in the volatility of the components between the compliant fuel and the non-compliant fuel to be identified, for example, a temperature that is lower than the temperature at which the amount of evaporation of the main component of the compliant fuel or the non-compliant fuel is at its maximum. Therefore, for example, if the heating time corresponds to the temperature, the timing of pressure detection is set to the time when the fuel reaches the predetermined detection temperature.

[0034] Next, the control unit 17 detects the pressure inside the heating pipe using the pressure gauge 145 (step ST6).

[0035] After measuring the pressure, the control unit 17 opens the valves 147 and 148 to return the fuel to the fuel tank 13 (step ST7).

[0036] Then, in step ST8, the control unit 17 identifies the properties of the fuel based on the detection result from the pressure gauge 145. That is, for example, if the measurement result from the pressure gauge 145 is less than a predetermined reference pressure value or within the reference pressure range, the control unit 17 determines that the fuel in the fuel tank 13 is genuine fuel (step ST9). On the other hand, if the detection value from the pressure gauge 145 is equal to or greater than the predetermined reference pressure value or outside the reference pressure range, the control unit 17 determines that the fuel in the fuel tank 13 is non-genuine fuel (step ST10). In this embodiment, the carbon-neutral synthetic fuel is the regular fuel and diesel is the irregular fuel. The reference pressure value or the reference pressure range is preset based on the evaporation amount of the carbon-neutral synthetic fuel, which is the regular fuel, at the detection temperature.

[0037] That is, the control unit detects the pressure in a temperature range where there is a difference in the degree of evaporation between the regular fuel and the non-regular fuel, and identifies the fuel properties based on the pressure value in that temperature range and the reference pressure value or reference pressure range. For example, if diesel, which is a non-regular fuel, is mixed into the fuel tank 13, the vapor pressure of the low-boiling point components will increase, while if only carbon-neutral synthetic fuel, which is a regular fuel, is present, the low-boiling point components will be scarce and the increase in vapor pressure of the main component may be small. In this case, the control unit determines that diesel is mixed in if the vapor pressure is equal to or greater than a predetermined reference pressure value, based on the pressure value in the low-boiling point temperature range where the difference occurs.

[0038] In this way, by setting the temperature range where the distribution of the amount of evaporation differs as the detection temperature, it is possible to distinguish between compliant fuel and non-compliant fuel from the detection result of the amount of evaporation, i.e., the vapor pressure inside the heating pipe 141. For example, a detection temperature range and a vapor pressure range corresponding to the detection temperature range can be set based on the volatility of the compliant fuel in question, and the control unit 17 can determine that the fuel is non-compliant when the detection result of the pressure gauge 145 falls outside the reference pressure range for that detection temperature range.

[0039] If the control unit 17 determines in step ST10 that the fuel is non-compliant, it notifies the user by displaying a message on a display device or emitting a warning sound (step ST11) to prompt the user to change the fuel. Alternatively, it may perform a restriction process, such as restricting the operation of the internal combustion engine 12 to restrict the use of the vehicle.

[0040] According to the vehicle 10 of this embodiment, by heating the fuel to a predetermined detection temperature, the fuel properties can be suitably estimated from the vapor pressure of the fuel. That is, by utilizing the fact that the amount of vaporized components differs depending on the relationship between the composition and volatility of diesel and synthetic fuel, and detecting the vapor pressure at a detection temperature where the volatility differs depending on the fuel composition, it becomes possible to determine that the fuel properties are inappropriate if the vapor pressure is outside a specific range, regardless of the type of synthetic fuel.

[0041] In the above embodiment, the detection temperature can be set lower than the peak temperature, so that the temperature can be set at a temperature at which the difference in the amount of evaporation is likely to occur, thereby improving the detection accuracy. That is, since the detection is performed at a point when evaporation occurs to some extent for fuels with a wide distribution range, while evaporation hardly occurs for fuels with a narrow distribution range, a significant pressure difference occurs between the two, making it easier to distinguish.

[0042] The present invention is not limited to the above embodiment. For example, the detection timing is not limited to when the opening / closing cap 132 of the fuel tank 13 is operated, but can be set as appropriate, such as periodically, when a command is given by the user via an input device, or when the internal combustion engine 12 is started.

[0043] The thresholds for judgment, such as the detected temperature and the reference pressure range, are set as appropriate. For example, the pressure value in one specific temperature range may be used, or multiple pressure values in multiple temperature ranges may be used to make the judgment. The judgment may also be based on the average value of multiple detected values. The numerical values and ranges that serve as the judgment criteria can be changed as appropriate. For example, the thresholds may be set in multiple stages. For example, if volatility increases in multiple temperature ranges for both genuine and non-genuine fuel, it is also possible to make the judgment using detected pressure values in multiple temperature ranges.

[0044] For example, while the above embodiment illustrates a case where the evaporation temperature range of the compliant fuel is narrow, the opposite is also possible. For example, if the temperature range of the non-compliant fuel is narrow, the detection temperature may be the temperature range where the evaporation rate of the compliant fuel is smaller than that of the non-compliant fuel. Furthermore, if the vapor pressure of low-boiling-point components increases in the compliant fuel, while the non-compliant fuel has fewer low-boiling-point components and a small increase in the vapor pressure of the main components, the fuel may be determined to be compliant if the detected pressure is equal to or greater than a predetermined value, and illegitimate if it is less than the predetermined value.

[0045] In the above embodiment, the fuel is determined to be regular if its pressure is within a predetermined range, but this is not limiting. For example, the reference range may be set based on the pressure value or pressure range of non-regular fuel.

[0046] Furthermore, the operation after the fuel property diagnosis is not limited to the notification process described above. For example, after the fuel property is identified, in addition to or instead of the notification process, the internal combustion engine 12 may be stopped, or may be driven up to a predetermined output and then stopped, or the operation of the internal combustion engine 12 may be restricted, such as by reducing the amount of fuel injection.

[0047] In the above embodiment, the control unit 17, which is the fuel property diagnostic device, is mounted on the vehicle 10, but the present invention is not limited to this. For example, the control unit 17 may be a terminal that can be retrofitted to the vehicle 10, or may be provided in an external terminal. Furthermore, for example, data detected in the vehicle 10 may be transmitted via wired or wireless communication to a terminal other than the vehicle 10, and diagnostic processing may be performed from the external terminal during maintenance, etc. For example, diagnostic processing may be performed on the external terminal using an app on a smartphone or the like.

[0048] Although one embodiment of the present invention has been described above in detail, the present invention is not limited to the above embodiment and can be appropriately modified, improved, etc. The present invention is defined by the claims and includes all modifications within the meaning and scope of the claims. [Explanation of symbols]

[0049] 10...vehicle, 12...internal combustion engine, 13...fuel tank, 14...vapor pressure detection unit, 16...driving unit, 17...control unit, 20...identification unit, 131...tank unit, 131a...supply port, 132...opening / closing cap, 132a...cap sensor, 133...fuel supply path, 133a...valve, 141...heating tube, 141a...accommodation unit, 141b...heater, 142...fuel passage, 142a...first passage, 142b...second passage, 142c...third passage, 143...pump, 145...pressure gauge, 146-148...valves.

Claims

1. a storage unit connected to a fuel tank that stores fuel to be supplied to an internal combustion engine and that heats the fuel; an identification unit that identifies the fuel property of the fuel based on the pressure inside the storage unit at a predetermined detected temperature; A vehicle equipped with:

2. 2. The vehicle according to claim 1, wherein the identification unit identifies whether the fuel is a regular fuel or a non-regular fuel having a different evaporativity from the regular fuel at the predetermined detection temperature based on a pressure inside the storage unit at the predetermined detection temperature.

3. 3. The vehicle according to claim 2, wherein the detected temperature is lower than a temperature at which the amount of evaporation of a main component of the regular fuel or the non-regular fuel becomes maximum.

4. the fuel tank includes a supply port through which fuel is supplied and an opening / closing cap that opens and closes the supply port, The vehicle according to claim 1 , wherein the identifying unit includes a control unit that sends fuel in the fuel tank to the storage unit when the opening / closing cap of the fuel tank is operated.

5. The vehicle according to claim 2 , further comprising a control unit that, when the identification unit determines that the fuel is the non-compliant fuel, performs a notification process or limits operation of an internal combustion engine to which the fuel is supplied.

6. a storage unit connected to a fuel tank that stores fuel to be supplied to an internal combustion engine and that heats the fuel; and a detection unit that detects the pressure of the storage unit. an identification unit that identifies a fuel property of the fuel based on a pressure in the accommodation unit at a predetermined detected temperature; A fuel property diagnostic device comprising:

7. an internal combustion engine; a fuel tank that stores fuel to be supplied to the internal combustion engine; and a storage unit that is connected to the fuel tank and heats the fuel; In a vehicle equipped with A fuel property diagnosis method for identifying fuel properties of the fuel based on the pressure in the accommodation portion at a predetermined detection temperature and based on the pressure in the accommodation portion and a predetermined reference pressure or reference pressure range.

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