Oil evaluation device, oil evaluation system, internal combustion engine-mounted device, oil evaluation method, and storage medium

Abstract

This oil evaluation device is provided with a calculation processing unit that calculates, on the basis of a measurement result of the density of oil in an internal combustion engine, the proportion of soot mixed into the oil as an evaluation index.

Description

TECHNICAL FIELD

[0001] The present application relates to an engine oil evaluation device, an engine oil evaluation system, an engine-mounted apparatus, an engine oil evaluation method, and a storage medium. BACKGROUND

[0002] In an engine of a vehicle that is an engine-mounted apparatus, soot is generated by combustion of fuel and engine oil, and the generated soot is mixed into the engine oil. Also, in the engine, since the soot has an effect of wearing out sliding parts, it is necessary to perform engine oil replacement on the used engine oil so that the mixing ratio of the soot into the engine oil does not exceed a reference level. The timing of the engine oil replacement is determined based on the operation time of the engine, the travel time of the vehicle, and visual inspection of the engine oil, and the like.

[0003] Here, in the engine, the mixing state of the soot into the engine oil differs depending on the operation condition including the rotational speed range during operation, the effect state of the load, and the operation environment, and the like. Therefore, from the viewpoint of performing engine oil replacement at an appropriate timing, it is sought to be able to accurately derive the mixing ratio of the soot into the engine oil in the engine. SUMMARY

[0004] The present application seeks to provide an engine oil evaluation device, an engine oil evaluation system, an engine-mounted apparatus, an engine oil evaluation method, and a storage medium that are capable of accurately deriving the mixing ratio of soot into engine oil in an engine.

[0005] In one aspect of the present application, an engine oil evaluation device has an arithmetic processing unit that calculates the mixing ratio of soot into engine oil as an evaluation index based on a measurement result of the density of engine oil in an engine.

[0006] According to the present application, it is possible to provide an engine oil evaluation device, an engine oil evaluation system, an engine-mounted apparatus, an engine oil evaluation method, and a storage medium that are capable of accurately deriving the mixing ratio of soot into engine oil in an engine. BRIEF DESCRIPTION OF DRAWINGS

[0007] Figure 1 is a schematic diagram showing one example of an engine oil evaluation system to which the embodiments relate.

[0008] Figure 2 is a schematic diagram showing one example of the relationship between the mixing ratio of water into engine oil and the resistance of engine oil.

[0009] Figure 3 is a flowchart schematically showing one example of a process of setting a reference density and a reference resistance value of engine oil by an engine oil evaluation device in the embodiments.

[0010] Figure 4is a flowchart that schematically shows a process of setting a reference density and a reference resistance value of engine oil by the engine oil evaluation device in the embodiment, and is different from one example of Figure 3

[0011] Figure 5 is a flowchart that schematically shows a process of setting a reference density of engine oil by the engine oil evaluation device in the embodiment, and is different from one example of Figure 3 Figure 4

[0012] Figure 6 is a flowchart that schematically shows one example of a calculation process of a mixing ratio of soot into engine oil by the engine oil evaluation device in the embodiment.

[0013] Figure 7 is a schematic diagram that describes one example of a calculation method of a mixing ratio of soot into engine oil in the embodiment.

[0014] Figure 8 is a schematic diagram that shows one example of a system that applies an evaluation result of engine oil for an internal combustion engine obtained by the engine oil evaluation device in the embodiment. DETAILED DESCRIPTION

[0015] Hereinafter, the embodiment will be described with reference to the drawings.

[0016] Figure 1 is a schematic diagram that shows one example of an engine oil evaluation system 1 to which the embodiment is applied. As shown in Figure 1 , the engine oil evaluation system 1 has a vehicle 2. The vehicle 2 has an internal combustion engine 3. The internal combustion engine 3 is, for example, a diesel engine, and can also be a gasoline engine. In the internal combustion engine 3, power is generated by combusting fuel such as diesel or gasoline. In addition, in the internal combustion engine 3, engine oil is used as lubricating oil or the like. Further, in the following description, the vehicle 2 is described as an example as an internal combustion engine mounting device that mounts the internal combustion engine 3. However, the processes and the like described below are also applicable even in a case where the internal combustion engine mounting device is other than the vehicle 2. As the internal combustion engine mounting device other than the vehicle 2, a stationary generator, an industrial machine, and a power source device are cited.

[0017] As shown in Figure 1 ​​​As shown, the internal combustion engine 3 has an oil pan 11, an oil pump 12, an oil filter 13, and a heat exchanger 15. In the internal combustion engine 3, oil is stored in the oil pan 11, and the oil of the oil pan 11 is pressurized and delivered to each supply target by the oil pump 12. In the internal combustion engine 3, the oil is supplied to each supply target by a supply flow path 16. In the internal combustion engine 3, as a supply target of the oil, for example, a crank mechanism 17 is provided. In the supply flow path 16, the oil filter 13 and the heat exchanger 15 are arranged between the oil pump 12 and the supply target, and Figure 1 In one example, the oil filter 13 and the heat exchanger 15 are arranged in this order from the side (upstream side) close to the oil pan 11. The oil filter 13 filters the oil, and the heat exchanger 15 cools the oil.

[0018] In the oil evaluation system 1, a measurer 18 is mounted on the vehicle 2, and the measurer 18 measures the density and the resistance of the oil in the internal combustion engine 3. In one example, the measurer 18 measures the temperature of the oil in the internal combustion engine 3 in addition to the density and the resistance of the oil in the internal combustion engine 3. As the measurer 18, a device that measures each parameter one by one can be provided, or all parameters can be measured by one device. In a preferred example including Figure 1 In one example, in the supply flow path 16, the density and the resistance of the oil are measured at a position on the downstream side with respect to the oil pump 12, and the measurement is performed between the oil pump 12 and the supply target. In Figure 1 In one example, in the supply flow path 16, the measurement performed by the measurer 18 is performed at a position between the heat exchanger 15 and the supply target. In one example, the measurement performed by the measurer 18 can be performed at any one of a position between the oil pump 12 and the oil filter 13 and a position between the oil filter 13 and the heat exchanger 15. In another example, the measurement can be performed at a position on the upstream side with respect to the oil pump 12, for example, at the oil pan 11.

[0019] The oil evaluation system 1 has an oil evaluation device 20. The oil evaluation device 20 has a processing execution unit 21 and a storage unit 22, and the processing execution unit 21 has an arithmetic processing unit 23. In the storage unit 22, a program or the like executed by the processing execution unit 21 is stored, and the arithmetic processing unit 23 performs at least a part of the processing executed by the processing execution unit 21. The processing execution unit 21 of the oil evaluation device 20 performs processing of evaluating the oil of the internal combustion engine 3. At this time, the processing execution unit 21 performs the processing by executing the oil evaluation program stored in the storage unit 22 or the like.

[0020] In Figure 1In one example, the engine oil evaluation device 20 is mounted on a vehicle, and is constituted by an in-vehicle server or the like in-vehicle computer. In this case, the processing execution section 21 is constituted by a processor or an integrated circuit or the like of the in-vehicle computer, and the processor or the like constituting the processing execution section 21 includes any one of an ECU (Electronic Control Unit), a CPU (Central Processing Unit), an ASIC (Application Specific Integrated Circuit), a microcomputer, an FPGA (Field Programmable Gate Array), a DSP (Digital Signal Processor), and the like. The processing execution section 21 can be constituted by one processor or the like, or can be constituted by a plurality of processors or the like. In addition, the storage section 22 is constituted by a storage medium, and has any one of a main storage medium including a memory and an auxiliary storage medium.

[0021] Further, in one example, at least a part of the processing executed by the processing execution section 21 is performed by a processor or the like of a computer outside the vehicle 2. In this case, the engine oil evaluation device 20 is constituted by one or more computers including the computer outside the vehicle 2. Further, in one example, the engine oil evaluation device 20 is constituted by a plurality of computers of a plurality of servers or the like, and the processors or the like of the plurality of computers perform cooperative operation to perform the processing described later by the processing execution section 21. In this case, for example, the processing based on the engine oil evaluation program is performed by one or more in-vehicle computers and one or more computers outside the vehicle 2 performing cooperative operation.

[0022] Further, in one example, at least a part of the engine oil evaluation device 20 is constituted by a cloud server of a cloud environment. The infrastructure of the cloud environment is constituted by a virtual CPU or the like virtual processor and a cloud storage. In a case where at least a part of the engine oil evaluation device 20 is constituted by the cloud server, at least a part of the processing based on the engine oil evaluation program described later is performed by the virtual processor. In this case, the program or the like executed by the virtual processor can also be stored in the cloud storage.

[0023] In one example, the engine oil evaluation device 20 is constituted by any one of an in-vehicle computer and a computer outside the vehicle 2, and the program executed by the processing execution section 21 is stored in a computer (server) or a cloud server or the like connected to the engine oil evaluation device 20 via a network. In this case, the processing execution section 21 downloads the program including the engine oil evaluation program via the network. Further, in one example, the engine oil evaluation device 20 is capable of communicating with any one of the other computers and the cloud server or the like by wireless or wired.

[0024] As described above, the engine oil evaluation device 20 is constituted by the processing execution section 21 and the storage section 22, and the engine oil evaluation program is stored in the storage section 22. Figure 1As shown, a user interface 25 is provided in the engine oil evaluation system 1. In Figure 1 In one example, the user interface 25 is constituted by a device mounted on the vehicle 2. However, in some examples, at least a part of the user interface 25 can also be constituted by a device outside the vehicle 2. In the user interface 25, various operations including operations related to the evaluation of the engine oil are input by a user of the engine oil evaluation device 20 or the like. Therefore, the user interface 25 has any one of a remote controller, a button, a mouse, a touch panel, a keyboard, and the like as an operation input section. In addition, a notification section in which various information is notified is provided in the user interface 25, and in the notification section, the information is notified by any one of a screen display and a sound emission. In some examples, information indicating the result of the evaluation of the engine oil for the internal combustion engine 3 is notified in the notification section.

[0025] In the internal combustion engine 3 of the vehicle 2, soot is generated due to the combustion of fuel and engine oil or the like, and the soot is mixed into the engine oil. Also, in the internal combustion engine 3, since the soot has an effect of wearing out sliding parts, it is necessary to perform engine oil replacement of the used engine oil so that the mixing ratio of the soot into the engine oil does not exceed a reference level. Here, the density of the engine oil in a state where it is not used is greater than or equal to 0.80 g / cm 3 and less than or equal to 0.87 g / cm 3 at room temperature. In contrast to this, the density of the soot is 1.8 g / cm 3 or so. Therefore, if the mixing ratio of the soot into the engine oil increases, the density of the engine oil increases.

[0026] In addition, in the internal combustion engine 3, water and fuel are mixed into the engine oil in addition to the soot. The density of the water is 1 g / cm 3 or so, which is higher than the density of the engine oil. Therefore, if the mixing ratio of the water into the engine oil increases, the density of the engine oil increases. On the other hand, in the case where the internal combustion engine 3 is a diesel engine, the density of the diesel oil as the fuel is greater than or equal to 0.76 g / cm 3 and less than or equal to 0.88 g / cm 3 or so, which is a value close to the density of the engine oil. In addition, in the internal combustion engine 3, the mixing ratio of the fuel into the engine oil is usually less than 1%. Therefore, the change in the density of the engine oil due to the mixing of the fuel into the engine oil is small.

[0027] As described above, the density of the engine oil in the internal combustion engine 3 changes due to the mixing of the soot and the water into the engine oil. Therefore, in a case where the density po of the engine oil changes from the reference density ρobase, an element Δρo indicating the change in the density of the engine oil is divided into an element Δρbys indicating the change in the density of the engine oil due to the mixing of the soot and an element Δρbyw indicating the change in the density of the engine oil due to the mixing of the water, and the relation of the formula (1) is established. Further, if the reference density ρobase of the engine oil, the density ρs of the soot, the mixing ratio Ws of the soot, the density ρw of the water, and the mixing ratio Ww of the water are used, the element Δρo becomes ρo-ρobase, the element Δρbys becomes (ρs-ρobase) x Ws, and the element Δρbyw becomes (ρw-ρobase) x Ww. Therefore, the relation of the formula (2) is established.

[0028] ρo-ρobase = Δρo = Δρbys + Δρbyw (1)

[0029] ρo-ρobase = (ρs-ρobase) x Ws + (ρw-ρobase) x Ww (2)

[0030] Further, the volume resistivity of each of the engine oil and the diesel oil as the fuel is greater than or equal to 1 x 10 14 Ω-cm and less than or equal to 2 x 10 14 Ω-cm, in contrast, the volume resistivity of the pure water is 6 x 10 5 Ω-cm, and the volume resistivity of the tap water is 5 x 10 3 Ω-cm. That is, the volume resistivity of the water is smaller than the volume resistivity of each of the engine oil and the diesel oil. Therefore, if the mixing ratio of the water into the engine oil increases, the resistance of the engine oil decreases. Further, the change in the resistance of the engine oil due to the mixing of the soot into the engine oil and the change in the resistance of the engine oil due to the mixing of the fuel into the engine oil are small. The soot has high electrical conductivity, but in the internal combustion engine 3, the soot mixed into the engine oil disperses. Therefore, the mixed soot has a small effect on the resistance of the engine oil.

[0031] Figure 2 is a schematic diagram indicating one example of the relation of the mixing ratio Ww of the water into the engine oil and the resistance of the engine oil. In Figure 2 , the curve is shown, on the horizontal axis, the mixing ratio Ww of the water is indicated by the mass percentage, and the vertical axis indicates the resistance of the engine oil. In Figure 2In one example, as the mixing ratio Ww of water into the engine oil increases, the resistance of the engine oil decreases in a range where the mixing ratio Ww is less than or equal to 1%. In addition, in the internal combustion engine 3, the mixing ratio of water into the engine oil is generally less than 1%. Therefore, by measuring the resistance of the engine oil in the internal combustion engine 3, the mixing ratio Ww of water can be derived based on the measurement result and the relationship between the mixing ratio Ww of water and the resistance of the engine oil.

[0032] In the present embodiment, the processing execution section 21 executes the engine oil evaluation program by the engine oil evaluation device 20, and the arithmetic processing section 23 calculates the mixing ratio of the soot into the engine oil in the internal combustion engine 3 as an evaluation index. At this time, the arithmetic processing section 23 calculates the mixing ratio of the soot using the aforementioned characteristics of the engine oil, the soot, and water. The evaluation result of the engine oil includes the calculation result of the mixing ratio of the soot. The calculation of the mixing ratio of the soot is performed, for example, periodically at a predetermined time interval. Thus, the chronological change in the mixing ratio of the soot is calculated for the engine oil of the internal combustion engine 3. Hereinafter, the processing based on the engine oil evaluation program including the arithmetic processing of the mixing ratio of the soot into the engine oil will be described.

[0033] In the processing based on the engine oil evaluation program, the arithmetic processing section 23 of the processing execution section 21 sets the reference for the density and the resistance of the engine oil of the internal combustion engine 3, respectively. Thus, the reference density ρobase is determined for the density of the engine oil, and the reference resistance value is determined for the resistance of the engine oil. At this time, the density of the engine oil injected into the internal combustion engine 3 by the engine oil replacement or the simple engine oil replenishment without extracting the engine oil, or the density of the engine oil in the internal combustion engine 3 in the state immediately after the engine oil replacement is set as the reference density ρobase. Also, the resistance of the engine oil injected into the internal combustion engine 3 by the engine oil replacement or the engine oil replenishment, or the resistance of the engine oil in the internal combustion engine 3 in the state immediately after the engine oil replacement is set as the reference resistance value. In addition, the arithmetic processing section 23 stores the set reference density ρobase and the reference resistance value in the storage section 22.

[0034] Figure 3 is a flowchart schematically showing one example of the processing by the engine oil evaluation device 20 in the embodiment to set the reference density ρobase and the reference resistance value of the engine oil. Figure 3 The processing of one example is performed, for example, periodically at a predetermined time interval. If the processing is started Figure 3 The processing of one example, the arithmetic processing section 23 determines whether or not the operation to reset the reference density ρobase and the reference resistance value of the engine oil is input to the user interface 25 or the like (S101). In the case where the operation to reset is not input (S101-No), the processing based on the engine oil evaluation program is ended. In the case where the operation to reset is input (S101-Yes), the processing based on the engine oil evaluation program is continued. Figure 3The processing of one example. On the other hand, in a case where the operation to perform resetting is input (S101-Yes), the processing execution unit 21 causes the measurer 18 to measure the density, the resistance, and the temperature of the oil in the internal combustion engine 3, and acquires the measurement results of the density, the resistance, and the temperature of the oil respectively (S102).

[0035] Then, the arithmetic processing unit 23 converts the measurement result of the density into the density at the reference temperature based on the measurement result of the temperature (S103), and converts the measurement result of the resistance into the resistance value at the reference temperature based on the measurement result of the temperature (S104). The conversion of the density uses data indicating the relationship between the temperature and the density of the oil stored in the storage unit 22 or the like, and the conversion of the resistance uses data indicating the relationship between the temperature and the resistance of the oil stored in the storage unit 22 or the like. Then, the arithmetic processing unit 23 sets the converted density as the reference density ρobase of the oil (S105), and sets the converted resistance value as the reference resistance value of the oil (S106).

[0036] In a case where the processing of one example is performed by the oil evaluation device 20, Figure 3 The user or the like of the oil evaluation device 20 inputs the aforementioned operation to perform resetting at the time of oil replacement each time. Thus, the reference density ρobase and the reference resistance value of the oil are set (updated) at the time of oil replacement each time. At this time, the density is set as the reference density ρobase and the resistance is set as the reference resistance value with respect to the oil in the internal combustion engine 3 in a state immediately after oil replacement. In addition, in one example, the aforementioned operation to perform resetting can be input in a case where simple oil replenishment is performed without extracting the oil. In this case, it is possible to set the density as the reference density ρobase and the resistance as the reference resistance value with respect to the oil in the internal combustion engine 3 in a state immediately after oil replenishment respectively.

[0037] Further, in the internal combustion engine 3, the oil is used in a temperature range of greater than or equal to -20°C and less than or equal to 120°C, and the temperature of the oil in the internal combustion engine 3 converges in a temperature range of greater than or equal to 80°C and less than or equal to 120°C after warm-up operation is performed. In one example, the measurer 18 can measure the density and the resistance of the oil in a temperature range of greater than or equal to 60°C and less than or equal to 100°C. Also, as the reference temperature, one or more temperatures in a temperature range of greater than or equal to 20°C and less than or equal to 100°C are set, and for example, 20°C, 25°C, and 40°C or the like are set as the reference temperature.

[0038] Figure 4 is a flowchart schematically indicating the processing performed by the oil evaluation device 20 in the embodiment to set the reference density ρobase and the reference resistance value of the oil, and is the same asFigure 3 One example is a different example. Figure 4 One example of this processing is performed during the period when the internal combustion engine 3 is stationary, or before the internal combustion engine 3 is started. Additionally, in Figure 4 In one example, an oil level sensor is installed in the internal combustion engine 3 to detect the height (position) of the oil level in the oil pan 11. Here, the oil level is unstable when the internal combustion engine 3 is running or immediately after it stops. Therefore, the processing execution unit 21 determines that the oil level is stable based on the following conditions: the time since the internal combustion engine 3 stopped is greater than or equal to a certain period; or the temperature difference between the coolant or lubricating oil in the internal combustion engine 3 and the temperature of the coolant or lubricating oil when the internal combustion engine 3 stopped is sufficiently large. Furthermore, when the processing execution unit 21 determines that the oil level is stable, it records the oil level height.

[0039] If start Figure 4 In one example of processing, the arithmetic processing unit 23 compares the real-time oil level measured in the internal combustion engine 3 with the previously recorded oil level. That is, the arithmetic processing unit 23 compares the real-time measurement result with the past record for the oil level (S111). At this time, the comparison is based on the detection result of the oil level sensor. Then, the arithmetic processing unit 23 determines, at least based on the comparison result of the oil level, whether an oil change or a simple oil top-up without removing oil has been performed (S112). At this time, the arithmetic processing unit 23 calculates the increase in the real-time recorded oil level relative to the past oil level recorded in the storage unit 22 of the internal combustion engine 3, and makes a determination based at least on the calculated increase. For example, the arithmetic processing unit 23 determines, at least based on the case where the aforementioned increase is greater than or equal to a reference increase, that either an oil change or an oil top-up has been performed.

[0040] Here, even if the oil level in the internal combustion engine 3 is at or near the lower limit, if the aforementioned increase is less than the reference increase, the processing unit 23 determines the data as uncertain, and neither determines that an oil change has been performed nor that an oil top-up has been performed. Furthermore, even if the aforementioned increase is greater than or equal to the reference increase, if either the vehicle 2's driving time since the last oil change or the internal combustion engine 3's operating time is shorter than the reference range, the processing unit 23 determines the data as uncertain, and neither determines that an oil change has been performed nor that an oil top-up has been performed.

[0041] In one example, the operation processing portion 23 records the set reference density ρobase and reference resistance value of the engine oil at each time of oil change at the last time and before that in the storage portion 22. Also, even if the aforementioned increase amount is greater than or equal to the reference increase amount, in the case where the difference between either of the reference density ρobase and reference resistance value of the engine oil derived through the processing described later and the value set at the time of past oil change exceeds the reference range, the operation processing portion 23 determines that the data is uncertain, neither determining that the oil change was performed nor determining that the oil supplement was performed. Also, compared to before the oil change, after the oil change, the proportion of soot mixed into the engine oil decreases, and the density of the engine oil changes. In one example, even if the aforementioned increase amount is greater than or equal to the reference increase amount, in the case where the change in the density of the engine oil before and after the internal combustion engine 3 is stopped is small to below the reference range, the operation processing portion 23 determines that the data is uncertain, neither determining that the oil change was performed nor determining that the oil supplement was performed. Further, in another example, in the case where the aforementioned increase amount is greater than or equal to the reference increase amount, but the change in the density of the engine oil before and after the internal combustion engine 3 is stopped is small to below the reference range, the operation processing portion 23 can determine that the oil change was not performed, but the oil supplement was performed, in which the engine oil was not extracted.

[0042] In the case where either of the oil change and the oil supplement is not determined to have been performed (S112-No), the processing of one example ends. Figure 4 On the other hand, in the case where either of the oil change and the oil supplement is determined to have been performed (S112-Yes), the processing execution portion 21 causes the measurer 18 to measure the density, resistance, and temperature of the engine oil at each of a plurality of measurement time points of the internal combustion engine 3, and acquires the measurement results of the density, resistance, and temperature of the engine oil at each of the plurality of measurement time points (S113). At this time, for example, the measurement is performed at each of the plurality of measurement time points during a period in which the temperature of the engine oil in the internal combustion engine 3 changes chronologically. Further, the measurement of the height of the liquid surface of the engine oil is performed in a state in which the liquid surface is stabilized, such as immediately before the start of the internal combustion engine 3, in contrast to which the measurement of the density, resistance, and temperature of the engine oil is performed in a state in which the internal combustion engine 3 is operating after the start of the internal combustion engine 3. Therefore, in S113, the measurement results of the density, resistance, and temperature of the engine oil are acquired at each of the plurality of measurement time points during the period in which the internal combustion engine 3 is operating. The operation processing portion 23 converts the measurement result of the density to the density at the reference temperature based on the measurement result of the temperature at each of the plurality of measurement time points (S114), and converts the measurement result of the resistance to the resistance value at the reference temperature (S115).

[0043] Then, the operation processing portion 23 performs averaging processing on the densities at the reference temperature calculated for the plurality of measurement time points (S116) and performs averaging processing on the resistances at the reference temperature calculated for the plurality of measurement time points (S117). Then, the operation processing portion 23 sets the average of the converted values of the densities at the plurality of measurement time points as the reference density ρobase of the engine oil (S118) and sets the average of the converted values of the resistances at the plurality of measurement time points as the reference resistance value (S119). Thus, for the engine oil in the internal combustion engine 3 in the state immediately after the engine oil replacement, the density is set to the reference density ρobase and the resistance is set to the reference resistance value.

[0044] In another example different from the one of Figure 3 and the one of Figure 4 , the user or the like of the engine oil evaluation device 20 can input an operation for setting the reference density ρobase and the reference resistance value in the user interface 25. In this case, the operation processing portion 23 sets the reference density ρobase and the reference resistance value based on the operation input in the user interface 25. In this example, the kind or the like of the engine oil injected into the internal combustion engine 3 at the time of engine oil replacement is recognized by the user or the like of the engine oil evaluation device 20, and the user of the engine oil evaluation device 20 inputs an operation in the user interface 25 based on the recognized kind or the like of the engine oil. In this example, for the engine oil injected into the internal combustion engine 3 at the time of engine oil replacement, the density is set to the reference density ρobase and the resistance is set to the reference resistance value.

[0045] Further, the reference density ρobase of the engine oil can also be set by the following method. Figure 5 is a flowchart that schematically shows the processing performed by the engine oil evaluation device 20 in the embodiment to set the reference density ρobase of the engine oil, and is an example different from the one of Figure 3 and the one of Figure 4 . Figure 5 The processing of the one example is executed, for example, at any one of each time of engine oil replacement and simple engine oil filling without engine oil extraction. If the processing of the one example of Figure 5 is started, the operation processing portion 23 acquires the measurement results of the density and the temperature of the engine oil in the internal combustion engine 3 in the state immediately after the engine oil replacement or the like (including engine oil replenishment). Then, the operation processing portion 23 calculates the reference density ρobase as in the one example of Figure 3 and calculates the density ρoafter of the engine oil at the reference temperature after the engine oil replacement or the like as in the one example of Figure 4 .

[0046] Then, the operation processing portion 23 calculates the proportion Wsafter of the soot mixed in the oil in the internal combustion engine 3 in the state immediately after the oil change (including oil replenishment) (S122). Here, even when the oil is drawn out of the internal combustion engine 3 at the time of the oil change, the oil remains in the oil filter 13 or the like. Therefore, even in the state immediately after the oil change, the soot is mixed in the oil. In addition, sometimes, a simple oil replenishment is performed in which the oil is not drawn out of the internal combustion engine 3 but the unused oil is replenished. The operation processing portion 23 calculates the proportion Wsafter of the soot mixed in, using the volume Vres of the oil remaining at the time of the oil change, the volume Vadd of the oil injected at the time of the oil change, and the proportion Wsbefore of the soot mixed in immediately before the oil change, as in Expression (3).

[0047]

[0048] Here, in the case where it is determined that the oil change is performed, the volume Vres of the oil remaining is calculated using a value determined in accordance with the specifications of the internal combustion engine 3 or the like. In addition, in the case where it is determined that the unused oil is replenished without the oil being drawn out (simple oil replenishment) is performed, the volume Vres of the oil remaining is calculated using the height of the liquid surface obtained by the oil level sensor before the oil replenishment, the volume and shape of the internal combustion engine 3 and the mounting member of the internal combustion engine 3. The operation processing portion 23 stores the calculated volume Vres in the storage portion 22. The volume Vadd of the oil injected can be recognized by the operator who performed the oil change. The user or the like of the oil evaluation device 20 can input information on whether the oil change is performed or whether the oil filling without the oil being drawn out is performed, and the volume Vadd of the oil injected, in the user interface 25. In addition, the volume Vadd can be calculated using the detection result of the height of the liquid surface of the oil level sensor, the volume and shape of the internal combustion engine 3 and the mounting member of the internal combustion engine 3, and the aforementioned volume Vres. In addition, the proportion Wsbefore of the soot mixed in immediately before the oil change can be calculated by deriving the proportion Wsof the soot mixed in by the processing described later before the oil change or the oil filling without the oil being drawn out.

[0049] The arithmetic processing portion 23 calculates the water mixing ratio Wwafter in the internal combustion engine 3 after the oil change or the like (including oil replenishment) (S123). In one example, the arithmetic processing portion 23 causes the meter to measure the resistance of the oil after the oil change or the like, and calculates the water mixing ratio Wwafter on the basis of the measurement result of the resistance. At this time, the water mixing ratio Wwafter after the oil change or the like is calculated in the same manner as the calculation of the water mixing ratio Ww on the basis of the resistance of the oil, which will be described later. In another example, the water mixing ratio Wwafter after the oil change or the like is calculated in the same manner as the calculation of the mixing ratio Wsafter, using the volume Vres of the oil remaining at the time of the oil change or the like, the volume Vadd of the oil injected at the time of the oil change or the like, and the water mixing ratio Wwbefore before the oil change or the like. Further, the water mixing ratio Wwbefore before the oil change or the like can be calculated by the following manner, that is, the water mixing ratio Ww is derived by the processing to be described later before the oil change or the like.

[0050] Then, the arithmetic processing portion 23 calculates the density of the oil injected into the internal combustion engine 3 by the oil change or the like (including oil replenishment) using the density poafter of the oil after the oil change or the like, the soot mixing ratio Wsafter after the oil change or the like, and the water mixing ratio Wwafter after the oil change or the like (S124). Then, the arithmetic processing portion 23 sets the calculation result of the density of the injected oil as the reference density po base of the oil (S125). Here, if the aforementioned formula (2) is modified, the reference density po base is derived as formula (4). In the processing of S124, in formula (4), the density poafter of the oil after the oil change or the like is substituted for the density po, the soot mixing ratio Wsafter after the oil change or the like is substituted for the mixing ratio Ws, and the water mixing ratio Wwafter after the oil change or the like is substituted for the mixing ratio Ww, respectively. Then, as the reference density po base, the density of the injected oil is calculated as formula (5).

[0051]

[0052] By performing the processing based on the oil evaluation program, the arithmetic processing portion 23 performs the calculation processing of the soot mixing ratio into the oil in the state where the reference density po base of the oil and the reference resistance value are set, in the same manner as any one of the aforementioned examples. Figure 6is a flowchart schematically showing one example of the operation processing of the mixing ratio Ws of soot into the engine oil by the engine oil evaluation device 20 in the embodiment. Figure 6 The processing of one example is performed periodically at a predetermined time interval after the engine oil is replaced, for example, after the reference density ρobase and the reference resistance value of the engine oil are set.

[0053] If the processing of one example is started Figure 6 The processing of one example, the operation processing section 23 causes the measurer 18 to measure the density, the resistance, and the temperature of the engine oil, and acquires the measurement results of the density, the resistance, and the temperature of the engine oil in real time (S131). Then, the operation processing section 23 converts the measurement result of the density into the density at the reference temperature based on the measurement result of the temperature (S132), and converts the measurement result of the resistance into the resistance value at the reference temperature (S133).

[0054] Then, the operation processing section 23 calculates the mixing ratio Ww of water into the engine oil in real time based on the converted resistance value (S134). At this time, the mixing ratio Ww of water in real time is calculated using the converted value of the resistance at the reference temperature and the data stored in the storage section 22 or the like, which shows the relationship between the mixing ratio Ww of water and the resistance of the engine oil at the reference temperature. In the data showing the relationship between the mixing ratio Ww of water and the resistance of the engine oil, a table or an approximate expression or the like that converts the resistance of the engine oil into the mixing ratio Ww is shown, and in one example, a table that shows the relationship between the resistance of the engine oil and the mixing ratio Ww of water is shown. Figure 2 The relationship between the mixing ratio Ww of water and the resistance of the engine oil shown in one example.

[0055] Then, the operation processing section 23 calculates the mixing ratio Ws of soot into the engine oil in real time based on the converted value of the density of the engine oil at the reference temperature and the calculation result of the mixing ratio Ww of water (S135). Thus, the mixing ratio Ws of soot into the engine oil is calculated based on the measurement result of the density ρo of the engine oil and the calculation result of the mixing ratio Ww of water into the engine oil. Here, if the aforementioned formula (2) is modified, the mixing ratio Ws of soot can be derived as formula (6). In the processing of S135, the operation processing section 23 calculates the mixing ratio Ws of soot by substituting appropriate values into the reference density ρobase and the density ρo of the engine oil, the density ρw of water, the density ρs of soot, and the mixing ratio Ww of water of formula (6), respectively. At this time, as the density ρo, the converted value that converts the measurement result into the density at the reference temperature is substituted, and as each density ρw, ρs, the values stored in the storage section 22 or the like are substituted. In addition, as the mixing ratio Ww of water, the calculation result in S134 is substituted.

[0056]

[0057] Figure 7 is a schematic diagram illustrating one example of a method of calculating the mixing ratio Wsof the soot into the oil in the embodiment. In Figure 7 , a graph in which the horizontal axis is the mixing ratio Wsof the soot and the vertical axis is the density poof the oil is shown, and the mixing ratio Wsis shown by the mass percentage. In addition, in Figure 7 , the relationship between the density poof the oil and the mixing ratio Wsof the soot in the case where no substance other than the soot such as water is mixed into the oil is shown by the line al. By the line al, the change in the density of the oil from the reference density po base corresponding to the mixing ratio Wsof the soot is shown for the case where no substance other than the soot is mixed into the oil.

[0058] In the embodiment, the mixing ratio Wsof the soot is calculated by the aforementioned formula (6). Therefore, based on the measurement result of the density of the oil, the element Δpo(= po- po base) indicating the change in the density of the oil is calculated, and based on the calculation result of the mixing ratio Wwof the water, the element Δρbyw(= (ρw-ρobase)×Ww) indicating the change in the density of the oil caused by the mixing of the water is calculated. Then, the element Δρbywindicating the change in the density of the oil caused by the mixing of the water is excluded from the element Δpoindicating the change in the density of the oil, and the mixing ratio Wsof the soot is calculated.

[0059] By excluding the element Δρbywindicating the change in the density caused by the mixing of the water, in one example of Figure 7 , the data point β1corresponding to the measurement result of the density moves to the data point β2on the line al (arrow A1). The mixing ratio Wsof the soot is calculated in accordance with the density at the data point β2and the relationship between the density poof the oil and the mixing ratio Wsof the soot shown by the line al.

[0060] In addition, in one example, the calculation processing portion 23 calculates the mixing ratio Wsof the soot based on the calculation result of the mixing ratio Wwof the water and the measurement result of the density of the oil, and also based on the measurement accuracy of the resistance and the density of the oil, and the like. Here, as described above, in the case where the mixing ratio Wwof the water is calculated, the measurement accuracy of the measurer 18 has an influence on the calculation result. In addition, in the case where the size of the soot particles mixed into the oil is large to exceed the reference range, the density of the soot also becomes large to exceed the reference range, and thus has an influence on the calculation result of the mixing ratio Wsof the soot.

[0061] Therefore, in this example, in addition to the base density ρobase and the density ρo of the engine oil, the density ρw of water, the density ρs of soot, and the mixing ratio Ww of water, a coefficient ks related to the change in the density of the engine oil caused by the mixing of soot and a coefficient kw related to the change in the density of the engine oil caused by the mixing of water are also used for the calculation of the mixing ratio Ws of soot. As described above, by defining the coefficients ks, kw, the element Δρo representing the change in the density of the engine oil satisfies the relation of Equation (7) with respect to the element Δρbys representing the change in the density of the engine oil caused by the mixing of soot and the element Δρbyw representing the change in the density of the engine oil caused by the mixing of water. Then, as with the transformation from Equation (1) to Equation (2), if Equation (7) is transformed, the relation of Equation (8) is satisfied.

[0062] Δρo = ks x Δρbys + kw x Δρbyw (7)

[0063] ρo - ρobase = ks x (ρs - ρobase) x Ws + kw x (ρw - ρobase) x Ww (8)

[0064] In addition, if Equation (8) described above is transformed, the mixing ratio Ws of soot is derived as in Equation (9). In this example, the calculation processing section 23 calculates the mixing ratio Ws of soot by substituting appropriate values into the base density ρobase and the density ρo of the engine oil, the density ρw of water, the density ρs of soot, the mixing ratio Ww of water, and the coefficients ks, kw of Equation (9), respectively. At this time, as the respective densities ρo, ρw, ρs and the mixing ratio Ww, the same values as those calculated by the calculation of the mixing ratio Ww by Equation (6) are substituted. The value of the coefficient ks is adjusted to an appropriate value in correspondence with the measurement accuracy of the density and the size of the mixed soot, etc. For example, in the case where the size of the mixed soot particles is large beyond the base range, etc., the coefficient ks is adjusted to a value smaller than that in the case where the size of the soot particles is in the base range. In addition, the value of the coefficient kw is adjusted to an appropriate value in correspondence with the measurement accuracy of the resistance, etc.

[0065]

[0066] In the engine oil evaluation device 20, the processing execution section 21 can also use the user interface 25 to notify the mixing ratio Ws of soot calculated as described above as an evaluation index. In this case, for example, the calculation result of the mixing ratio Ws of soot is notified by any one of a screen display and a sound emission, etc. In addition, the processing execution section 21 can also transmit the evaluation result of the engine oil including the calculation result of the mixing ratio Ws of soot to a computer (server) or a cloud server different from the engine oil evaluation device 20.

[0067] As described above, in the embodiment and the like, the proportion of the soot mixed into the oil Ws is calculated as an evaluation index based on the result of the measurement of the density of the oil in the internal combustion engine 3. The density of the soot is higher than the density of the oil. Therefore, the proportion of the soot mixed Ws can be accurately derived based on the chronological change and the like of the density of the oil up to the density of the measurement result. In addition, in the embodiment and the like, the proportion of the water mixed into the oil Ww is calculated based on the result of the measurement of the resistance of the oil in the internal combustion engine 3, and the proportion of the soot mixed Ws is calculated based on the result of the measurement of the density of the oil and the calculation result of the proportion of the water mixed Ww. Therefore, the proportion of the soot mixed Ws is accurately derived also taking into account the mixing of the water into the oil.

[0068] In addition, in a case where the proportion of the soot mixed Ws is calculated using any one of the equation (6) and the equation (9), the element Δρo indicating the change in the density of the oil is calculated based on the result of the measurement of the density of the oil, and the element Δρbyw indicating the change in the density of the oil due to the mixing of the water is calculated based on the calculation result of the proportion of the water mixed Ww. Then, the element Δρbyw indicating the change in the density of the oil due to the mixing of the water is excluded from the elements Δρ indicating the change in the density of the oil, and the proportion of the soot mixed Ws is calculated. Therefore, the proportion of the soot mixed Ws is accurately derived even in a state where the water is mixed into the oil.

[0069] In addition, in some examples of the embodiment and the like, the result of the measurement of the resistance of the oil is converted into a resistance value at a reference temperature based on the result of the measurement of the temperature of the oil in the internal combustion engine 3, and the proportion of the water mixed Ww is calculated based on the converted resistance value. Then, the result of the measurement of the density of the oil is converted into a density at a reference temperature based on the result of the measurement of the temperature of the oil, and the proportion of the soot mixed Ws is calculated based on the converted density. Therefore, the proportion of the water mixed Ww and the proportion of the soot mixed Ws are accurately calculated even in a case where the resistance and the density of the oil are measured in an environment where the temperature of the oil chronologically changes. In addition, in a case where the proportion of the soot mixed Ws is calculated using the equation (9), the proportion of the soot mixed Ws is calculated based on the calculation result of the proportion of the water mixed Ww and the result of the measurement of the density of the oil, and based on the measurement accuracy and the like of each of the resistance and the density of the oil. Therefore, the proportion of the soot mixed Ws is more accurately derived.

[0070] In addition, in some examples of the embodiment and the like, the density of the engine oil to be injected into the internal combustion engine 3 at the time of engine oil replacement, or the density of the engine oil in the internal combustion engine 3 in a state immediately after engine oil replacement is set as the reference density ρobase. Then, the mixing ratio Wsof the soot into the engine oil is calculated based on the density variation of the density of the engine oil corresponding to the reference density ρobase. Thus, the density of the engine oil in a state in which the soot is not mixed or almost not mixed is appropriately set as the reference density ρobase. Then, the mixing ratio Wsof the soot is calculated based on the variation of the density of the engine oil from the reference density ρobase which is appropriately set, and thus the mixing ratio Wsis more accurately derived.

[0071] In addition, in a preferred example of the embodiment, the density and the resistance and the like of the engine oil are measured at a position on the supply flow path 16 of the engine oil of the internal combustion engine 3 on the downstream side with respect to the oil pump 12, that is, at a position between the oil pump 12 and the supply target. Here, in the oil pan 11, air flows into the stored engine oil, and the air is sucked into the engine oil as bubbles, and the bubbles deteriorate the measurement accuracy of the density and the resistance and the like of the engine oil. In this example, the density and the resistance and the like of the engine oil are measured between the oil pump 12 in which the pressure is increased and the supply target, and thus the density and the resistance and the like of the engine oil are measured almost free from the influence of the bubbles of the air. Thus, the density and the resistance and the like of the engine oil are accurately measured, and the mixing ratio Wsof the soot into the engine oil is more accurately derived.

[0072] As described above, in the embodiment and the like, the mixing ratio Wsof the soot into the engine oil is accurately derived. Thus, the user of the engine oil evaluation device 20 and the like can accurately determine whether or not to perform engine oil replacement of the internal combustion engine 3 based on the derived mixing ratio Wsof the soot. Thus, the engine oil replacement can be performed at an appropriate timing based on the derivation result of the mixing ratio Wsof the soot.

[0073] Further, for example, in a case in which the resistance and the density of the engine oil are measured only at a temperature of the reference temperature and in the vicinity thereof and the like, it is not necessary to perform the process of converting the measurement result to the density and the resistance value at the reference temperature. In addition, for example, in a case in which it is clear in advance that water is almost not mixed into the engine oil and the like, it is not necessary to perform the measurement of the resistance of the engine oil and the operation process of the mixing ratio Wwof the water. In this case, the operation processing portion 23 sets the mixing ratio Wwof the water to 0%, for example, and calculates the mixing ratio Wsof the soot into the engine oil based on the measurement result of the density of the engine oil.

[0074] Figure 8 is a schematic diagram showing an example of a system which applies the evaluation result for the engine oil of the internal combustion engine 3 obtained by the engine oil evaluation device 20 in the embodiment. In Figure 8In a system of one example, in addition to the engine oil evaluation device 20, there are a monitoring server 31, a user computer 32, a dealer computer 33, and a design-side computer 35. The monitoring server 31 is constituted by a computer or a cloud server that is different from the engine oil evaluation device 20. The monitoring server 31 performs monitoring related to the internal combustion engine with respect to vehicles that are on the market, including the vehicle 2.

[0075] The engine oil evaluation device 20 transmits, to the monitoring server 31, the evaluation result of the engine oil for the internal combustion engine 3 including the mixed proportion Ws of the soot calculated as the evaluation index. The engine oil evaluation device 20 transmits the derivation result of the mixed proportion Ws of the soot each time the operation processing of the mixed proportion Ws of the soot is performed. Thus, the monitoring server 31 acquires the chronological change in the mixed proportion Ws of the soot into the engine oil with respect to the internal combustion engine 3 of the vehicle 2. The monitoring server 31 can predict the timing of replacement of the engine oil in the internal combustion engine 3 of the vehicle 2 on the basis of the chronological change in the mixed proportion Ws of the soot or the like. In this case, information related to the maintenance and management of the internal combustion engine 3 including the timing of replacement of the engine oil is generated.

[0076] Further, in some examples, at least a part of the aforementioned processing performed by the engine oil evaluation device 20 can also be performed by the monitoring server 31. In this case, for example, the measurement results of the density and the resistance of the engine oil in the internal combustion engine 3 each, the liquid level of the engine oil, and information of the user interface or the like are transmitted to the monitoring server 31 that becomes the engine oil evaluation device 20. Then, the monitoring server 31 derives the mixed proportion Ww of the water into the engine oil and the mixed proportion Ws of the soot or the like as described above.

[0077] The user computer 32 is constituted by a terminal or a server or the like used by the user of the vehicle 2. In addition, the dealer computer 33 is constituted by a terminal or a server or the like used by the dealer of the vehicle that is on the market, including the vehicle 2. The monitoring server 31 transmits any of information indicating the evaluation result of the engine oil of the internal combustion engine 3 and information related to the maintenance and management of the internal combustion engine 3 of the vehicle 2 or the like to the user computer 32 and the dealer computer 33, respectively. The user of the vehicle 2 performs, on the basis of the information received by the user computer 32 from the monitoring server 31, the entrustment of the vehicle 2 to the dealer, the consultation related to the vehicle 2, and the provision of the data related to the vehicle 2 or the like. On the other hand, the dealer performs, on the basis of the information received by the dealer computer 33 from the monitoring server 31, the support and the guarantee related to the vehicle 2, the suggestion of the replacement of the engine oil and the replacement of the parts or the like, and the provision of the plan related to the vehicle 2 or the like to the user of the vehicle 2.

[0078] In addition, in the above-described example, the engine oil evaluation device 20 can be constituted by a terminal or a server or the like used by the user of the vehicle 2. Figure 8In one example, the monitoring server 31 generates information related to the operation state of the internal combustion engine 3 based on the temporal change in the mixing ratio Ws of the soot, and the like. In the information related to the operation state of the internal combustion engine 3, it is shown how the internal combustion engine 3 has been operated so far, and the like. The design-side computer 35 is constituted by a terminal or a server, or the like, used by a designer of the vehicle 2 being circulated on the market, and in particular, a designer of the internal combustion engine of the vehicle being circulated on the market. The monitoring server 31 transmits the information related to the operation state of the internal combustion engine 3 to the design-side computer 35. Thereby, the operation state of the internal combustion engine 3 is fed back to the designer of the internal combustion engine 3. The designer of the internal combustion engine 3 supports the market in which the vehicle is circulated based on the information from the monitoring server 31. In addition, the designer updates the equipment and products used by the internal combustion engine and the vehicle, and the like, including software, based on the information from the monitoring server 31.

[0079] Further, the present application is not limited to the above-described embodiments, and various modifications can be made in the implementation stage without departing from the scope of the gist thereof. In addition, the respective embodiments can be implemented in appropriate combination, and in this case, the effects after the combination are obtained. Also, various applications are included in the above-described embodiments, and various applications can be extracted by a combination selected from the disclosed plurality of structural elements. For example, in the case where the problem can be solved and the effects can be obtained even if several structural elements are deleted from all the structural elements shown in the embodiments, the structure after the deletion of the structural elements can also be extracted as an application.

Claims

1. An engine oil evaluation device, comprising a calculation processing unit, wherein the calculation processing unit calculates the proportion of carbon soot mixed into the engine oil as an evaluation index based on the measurement result of the density of engine oil in an internal combustion engine.

2. The oil evaluation device according to claim 1, wherein, The processing unit calculates the proportion of water mixed into the engine oil based on the measured resistance of the engine oil in the internal combustion engine. In addition to the measurement result of the density of the engine oil, the processing unit also calculates the mixing ratio of carbon soot into the engine oil based on the calculation result of the mixing ratio of water.

3. The oil evaluation device according to claim 2, wherein, When the processing unit calculates the mixing ratio of the soot, Based on the measurement results of the density of the engine oil, a factor representing the density change of the engine oil is calculated. Based on the calculation results of the water mixing ratio, an element representing the density change of the engine oil caused by the mixing of water is calculated. The soot mixing ratio is calculated by excluding the elements representing the density change of the engine oil caused by the mixing of water from the elements representing the density change of the engine oil.

4. The oil evaluation device according to claim 2, wherein, When calculating the mixing ratio of water, the processing unit converts the measured resistance of the engine oil in the internal combustion engine into a resistance value at a reference temperature based on the measured temperature of the engine oil, and calculates the mixing ratio of water based on the converted resistance value.

5. The oil evaluation device according to claim 2, wherein, When calculating the mixing ratio of the soot, the processing unit calculates the mixing ratio of the soot based not only on the calculation result of the mixing ratio of the water and the measurement result of the density of the engine oil, but also on the measurement accuracy of the resistance and density of the engine oil.

6. The oil evaluation device according to claim 1, wherein, When calculating the mixing ratio of the soot, the processing unit converts the measured density of the engine oil into the density at a reference temperature based on the measured temperature of the engine oil, and calculates the mixing ratio of the soot based on the converted density.

7. The oil evaluation device according to claim 1, wherein, The processing unit sets the density of the engine oil injected into the internal combustion engine, or the density of the engine oil in the internal combustion engine after an oil change, as the reference density. When calculating the mixing ratio of the soot, the processing unit calculates the mixing ratio of the soot into the engine oil based on the density change of the measured density of the engine oil corresponding to the reference density.

8. An engine oil evaluation system, comprising: The oil evaluation device according to any one of claims 1 to 7; A vehicle having the internal combustion engine, and the proportion of carbon soot from the internal combustion engine mixed into the engine oil is calculated by the engine oil evaluation device; as well as A measuring instrument for measuring the density of the engine oil in the internal combustion engine.

9. An internal combustion engine mounting device, comprising: The oil evaluation device according to any one of claims 1 to 7; The internal combustion engine, through the oil evaluation device, calculates the proportion of carbon soot mixed into the engine oil currently in use; and A measuring instrument for measuring the density of the engine oil in the internal combustion engine.

10. A method for evaluating engine oil, comprising the following steps: calculating the proportion of carbon soot mixed into the engine oil as an evaluation index based on the measurement results of the density of engine oil in an internal combustion engine.

11. A storage medium storing an oil evaluation program, the oil evaluation program enabling a computer to calculate, based on the density measurement results of the oil in an internal combustion engine, the proportion of carbon soot mixed into the oil as an evaluation index.

Images