JP2024080504A - Engine parts deterioration diagnosis system - Google Patents

Abstract

To provide an engine component deterioration diagnosis system capable of accurately estimating a degree of deterioration of various engine components in addition to a fuel filter.SOLUTION: An engine component deterioration diagnosis system (10) estimates a degree of deterioration of at least one engine component out of a plurality of engine components constituting an engine (20) that is mounted on a vehicle and generates driving force by burning fuel containing gasoline and alcohol. One of the plurality of engine components is a rotating component. The engine component deterioration diagnosis system (10) estimates a degree of deterioration of at least one engine component out of the plurality of engine components on the basis of indicated mean effective pressure (Pmi) during driving of the engine (20) and cumulative rotational frequency (Rd) of the rotating component.SELECTED DRAWING: Figure 1

Description

The present invention relates to an engine part deterioration diagnosis system that estimates the deterioration level of at least one of a plurality of engine parts that constitute an engine mounted on a vehicle. In particular, the present invention relates to an engine part deterioration diagnosis system that estimates the deterioration level of a plurality of engine parts that constitute an engine that generates driving force by burning fuel that contains gasoline and alcohol.

Patent Document 1 discloses a technology that allows a vehicle equipped with an engine that can use fuel containing gasoline and alcohol to know the best time to perform maintenance on a fuel filter. In the vehicle described in Patent Document 1, the value of a first parameter is counted when the alcohol content of the fuel is equal to or greater than a first reference ratio at which foreign matter is assumed to be likely to accumulate. When the value of this first parameter reaches a first judgment value at which it is assumed that the fuel filter needs to be replaced, the user is notified of this fact. This allows the user to recognize that there is a high possibility that the fuel filter is clogged, and makes it possible to know the best time to perform maintenance on the fuel filter.

JP 2013-209927 A

However, when an engine is driven using fuel containing gasoline and alcohol, the lower the alcohol content of the engine parts that make up the engine, the lower the compression ratio and retarded ignition timing to prevent knocking, making it difficult to produce power, so the engine speed is increased, the amount of air is increased, and the engine is operated under high engine load, which makes it more likely to deteriorate due to damage. On the other hand, the higher the alcohol content of the fuel, the less likely knocking occurs, so the engine can be operated under high compression ratio and advanced ignition timing to make it easier to produce power, so the engine speed can be reduced, the amount of air is reduced, and the engine is operated under low load to reduce damage, but the influence of alcohol properties becomes greater, and deterioration due to corrosion tends to progress more easily. Therefore, unlike a fuel filter that can estimate the degree of deterioration according to the alcohol content as in Patent Document 1, it is difficult to estimate the overall degree of deterioration of engine parts, etc., unless both the deterioration according to the alcohol concentration and the influence of damage from the engine load are taken into consideration.

The present invention provides an engine component deterioration diagnosis system that can accurately estimate the degree of deterioration of not only fuel filters but also various other engine components.

The present invention relates to
An engine component deterioration diagnosis system that estimates a deterioration degree of at least one of a plurality of engine components that constitute an engine that is mounted on a vehicle and generates driving force by burning a fuel containing gasoline and alcohol, comprising:
one of the plurality of engine components is a rotating component;
An indicated mean effective pressure when the engine is running; and
A cumulative number of rotations of the rotating component; and
A deterioration level of at least one of the plurality of engine parts is estimated based on the above.

The present invention makes it possible to accurately estimate the degree of deterioration of not only fuel filters but also various engine parts.

1 is a block diagram of an engine component deterioration diagnosis system and an engine according to an embodiment of the present invention. 2 is a diagram showing an example of an indicated mean effective pressure reference map for each alcohol content, stored in an indicated mean effective pressure reference map storage unit in the engine part deterioration diagnosis system of FIG. 1 . FIG. 2 is a flowchart (part 1) showing an engine part deterioration diagnosis flow in the engine part deterioration diagnosis device of FIG. 1 . 2 is a flowchart (part 2) showing the engine part deterioration diagnosis flow in the engine part deterioration diagnosis device of FIG. 1 . 2 is a diagram showing an example of an engine state frequency ratio map for a predetermined traveling distance, which is created by an engine state frequency ratio map creation unit in the engine part deterioration diagnosis system of FIG. 1 . FIG. 2 is a diagram showing an example of an indicated mean effective pressure frequency map created by an indicated mean effective pressure frequency map creation unit in the engine part deterioration diagnosis system of FIG. 1 . FIG. 2 is a diagram showing an example of a time-frequency map created by a time-frequency map creating unit in the engine part deterioration diagnosis system of FIG. 1 . FIG. 2 is a diagram showing an example of a crankshaft rotation speed map created by a crankshaft cumulative rotation speed calculation unit in the engine part deterioration diagnosis system of FIG. 1 . FIG.

Below, one embodiment of the engine component deterioration diagnosis system of the present invention will be described with reference to the attached drawings. Note that the drawings should be viewed in the direction indicated by the reference symbols.

As shown in FIG. 1, the engine component deterioration diagnosis system 10 of this embodiment estimates the degree of deterioration of engine components that make up the engine 20 installed in a vehicle.

The engine 20 mounted on the vehicle is an engine that generates driving force by burning fuel containing gasoline and alcohol, and is, for example, a reciprocating engine. The alcohol contained in the fuel is, for example, ethanol. The alcohol contained in the fuel may be other alcohols, such as methanol.

The engine part deterioration diagnosis system 10 includes an engine part deterioration diagnosis device 11 that estimates the degree of deterioration of engine parts that constitute the engine 20. The engine part deterioration diagnosis device 11 is mounted, for example, on a vehicle in which the engine 20 is mounted.

The engine 20 is equipped with a concentration sensor 21 that detects the concentration of alcohol contained in the fuel, a crank pulse sensor 22 that detects the rotation speed of the crankshaft, and a throttle opening sensor 23 that detects the throttle opening.

Engine parts constituting the engine 20 include sliding parts. The sliding parts include rotating sliding parts and reciprocating sliding parts. The rotating sliding parts include a crankshaft, a balancer shaft, a camshaft, etc. The rotating sliding parts may further include an oil pump shaft, a main shaft and a countershaft of a transmission mechanism, a rotating shaft of a turbocharger, etc. The engine parts include reciprocating sliding parts. The reciprocating sliding parts include pistons, piston rings, intake valves, exhaust valves, intake valve seats, exhaust valve seats, etc. The engine parts also include parts that the sliding parts come into contact with. The parts that the sliding parts come into contact with include various bearings that support the rotating sliding parts, cylinders, intake valve guides, exhaust valve guides, connecting rods, etc.

<Engine parts deterioration diagnosis device>
The engine part deterioration diagnosis device 11 estimates the deterioration degree of engine parts constituting the engine 20 that generates driving force by burning fuel containing gasoline and alcohol. The engine part deterioration diagnosis device 11 is capable of estimating the deterioration degree of each engine part constituting the engine 20.

The engine part deterioration diagnosis device 11 includes an indicated mean effective pressure reference map memory unit 111 that stores a plurality of indicated mean effective pressure reference maps that have been created in advance in response to the alcohol content of the fuel, a deterioration model memory unit 112 that stores a deterioration model due to damage and a deterioration model due to corrosion that have been created for each engine part that constitutes the engine 20, an alcohol content acquisition unit 113 that acquires the alcohol content of the fuel, an engine operating time acquisition unit 114 that acquires the operating time of the engine 20 since the completion of the previous engine part deterioration diagnosis, an engine state frequency ratio map creation unit 115a that creates an engine state frequency ratio map of crankshaft rotation speed Ne-throttle opening Th, and a frequency map of indicated mean effective pressure Pmi. The engine 20 includes an indicated mean effective pressure frequency map creating unit 115b, a time frequency map creating unit 115c that creates a time frequency map of crankshaft rotation speed Ne-throttle opening Th, a crankshaft cumulative rotation speed calculating unit 115d that calculates the cumulative rotation speed of the crankshaft, a damage deterioration degree calculating unit 116a that calculates the deterioration degree due to damage of each engine part that constitutes the engine 20, a corrosion deterioration degree calculating unit 116b that calculates the deterioration degree due to corrosion of each engine part that constitutes the engine 20, an optimal alcohol content calculating unit 117 that calculates the optimal alcohol content of the fuel to be used, an engine part state storing unit 118 that stores the state of each engine part that constitutes the engine 20, a notification unit 119, and an engine part information storing unit 120. The crankshaft rotation speed Ne is the number of rotations of the crankshaft per minute.

An example of an indicated mean effective pressure reference map that has been created in advance in response to the alcohol content of the fuel stored in the indicated mean effective pressure reference map storage unit 111 is shown in Figure 2.

As shown in FIG. 2, the indicated mean effective pressure reference map is a table with the horizontal axis representing the crankshaft rotation speed Ne [rpm] and the vertical axis representing the throttle opening Th [%].

The crankshaft rotation speed Ne on the horizontal axis can be, for example, 1500 [rpm] or less, more than 1500 [rpm] and less than 2000 [rpm], more than 2000 [rpm] and less than 2500 [rpm], more than 2500 [rpm] and less than 3000 [rpm], more than 3000 [rpm] and less than 3500 [rpm], more than 3500 [rpm] and less than 4000 [rpm], more than 4000 [rpm] and less than 4500 [rpm], more than 4500 [rpm] and less than 5000 [rpm], more than 5000 [rpm] and less than 5500 [rpm], more than 5500 [rpm] and less than 6000 [rpm], and less than 6000 [rpm]. They are classified as follows: over 6500 rpm, over 6500 rpm and under 7000 rpm, over 7000 rpm and under 7500 rpm, over 7500 rpm and under 8000 rpm, over 8000 rpm and under 8500 rpm, over 8500 rpm and under 9000 rpm, over 9000 rpm and under 9500 rpm, over 9500 rpm and under 10000 rpm, over 10000 rpm and under 10500 rpm, over 10500 rpm and under 11000 rpm, and over 11000 rpm.

The throttle opening degree Th on the vertical axis is classified into, for example, 0%; more than 0% and less than 10%; more than 10% and less than 20%; more than 20% and less than 30%; more than 30% and less than 40%; more than 40% and less than 50%; more than 50% and less than 60%; more than 60% and less than 70%; more than 70% and less than 80%; more than 80% and less than 90%; and more than 90% (less than 100%).

The indicated mean effective pressure Pmi [kPa] is recorded in the cells corresponding to the crankshaft rotation speed Ne and the throttle opening Th.

The indicated mean effective pressure Pmi [kPa] is the work volume per cycle divided by the engine's stroke volume, and is calculated using the following formula (1):

Pmi [kPa] = Pme [kPa] + Pmf [kPa] ... (1)

Pme is the net mean effective pressure, which is calculated using the following formula (2).

Pme [kPa] = (12 x 10^4 x P) / (Ne x Vst) ... (2)

P [kW] is the corrected pressure in the cylinder of engine 20 per cycle, Ne [rpm] is the crankshaft rotation speed Ne mentioned above, and Vst [l] is the total stroke volume in the cylinder of engine 20 per cycle.

Pmf is the friction loss mean effective pressure, which is calculated using the following formula (3).

Pmf [kPa] = (12 x 10^4 x Psf) / (Ne x Vst) ... (3)

Psf [kW] is the friction loss per cycle in the cylinder of engine 20, Ne [rpm] is the crankshaft rotation speed Ne mentioned above, and Vst [l] is the total stroke volume per cycle in the cylinder of engine 20.

In this embodiment, the indicated mean effective pressure Pmi [kPa] corresponding to each of the crankshaft rotation speed Ne and the throttle opening Th is obtained by testing on a test bench or the like before the engine 20 is installed in the vehicle. If a pressure sensor/intake and exhaust pressure sensor is attached to the engine 20, an on-board combustion analysis of the engine 20 may be performed to calculate the indicated mean effective pressure Pmi [kPa].

Then, an indicated mean effective pressure reference map for each of the following cases where the alcohol content of the fuel is, for example, 0%; more than 0% and not more than 10%; more than 10% and not more than 20%; more than 20% and not more than 30%; more than 30% and not more than 40%; more than 40% and not more than 50%; more than 50% and not more than 60%; more than 60% and not more than 70%; more than 70% and not more than 80%; more than 80% and not more than 90%; and more than 90% (not more than 100%). is created before the engine 20 is mounted on the vehicle, and stored in the indicated mean effective pressure reference map storage unit 111.

The damage degradation model created for each engine part constituting the engine 20 and stored in the degradation model storage unit 112 is a predetermined value [kPa x 10,000 times] expressed by the indicated mean effective pressure Pmi [kPa] x the cumulative number of crankshaft revolutions [10,000 times] x the wear rate α. In this specification, this value is called the damage degradation value.

The wear rate α is a predetermined coefficient calculated by the following equation (4).
α=f(Ne, TRQ) (4)

Ne is the crankshaft rotation speed Ne mentioned above, and TRQ is the torque input to the engine part. The wear rate α is determined by individual tests of each engine part. The wear rate is generally a value between 0.4 and 0.8. The wear rate α of each engine part is stored in advance in the engine part information storage unit 120.

For example, in a model of the degree of deterioration due to damage to a specific engine part, the damage deterioration value = 4,500,000 [kPa x 10,000 times] is the limit damage deterioration value, which is the limit life of the engine part, and 4,000,000 [kPa x 10,000 times] is set as the damage deterioration value requiring replacement, which requires replacement of the engine part.

The engine parts that make up the engine 20 are more likely to deteriorate due to corrosion in an environment with a higher alcohol content [%] of the fuel. The corrosion deterioration model created for each engine part that makes up the engine 20 and stored in the deterioration model storage unit 112 is a predetermined value [kPa x 10,000 times] expressed by (alcohol content [%] of the fuel/100) x indicated mean effective pressure Pmi [kPa] x cumulative number of crankshaft revolutions [10,000 times] x corrosion rate β. In this specification, this value is called the corrosion deterioration value.

The corrosion rate β is a predetermined coefficient determined by the following equation (5).
β = 8.954 × (M / n) × i _corr ... (5)

M is the atomic weight of the engine part material, and n is the electron valence when the engine part material melts.

Moreover, i _corr is the corrosion current density [A/m ² ] and is calculated by the following formula (6).
i _corr = K / Rp (6)

K is a constant determined by the combination of the material of the engine part and the alcohol that causes corrosion, and Rp is the polarization resistance. The polarization resistance is the slope of the linear part of the polarization curve near the corrosion potential, and is the value obtained by dividing the polarization value of the potential by the current. The corrosion rate β is generally a value between 50 and 1000. The corrosion rate β of each engine part is stored in advance in the engine part information storage unit 120.

The corrosion rate β may be determined by individual testing of each engine part. For example, a corrosion test may be performed on each engine part to experimentally determine the corrosion rate β. For example, a corrosion test may be performed using fuel with an alcohol content of 100%, and the corrosion rate β may be calculated as follows: corrosion potential - natural potential / year.

For example, in a model of the degree of deterioration due to corrosion of a specific engine part, 2,250,000,000 [kPa-10,000 times] is set as the limit corrosion deterioration value, which is the limit life of the engine part, and 2,000,000,000 [kPa-10,000 times] is set as the replacement corrosion deterioration value, which requires replacement of the engine part.

The engine component status storage unit 118 stores information indicating the status of the engine components, including the latest replacement timing of each engine component that constitutes the engine 20, the damage degradation value [kPa x 10,000 times], corrosion degradation value [kPa x 10,000 times], damage degradation degree [%], corrosion degradation degree [%], etc., calculated and estimated for each time in the engine component degradation diagnosis described below.

The engine part information storage unit 120 stores in advance information about each engine part, including the wear rate α and corrosion rate β of each engine part.

<Engine parts deterioration diagnosis flow>
Next, the engine component deterioration diagnosis flow in the engine component deterioration diagnosis device 11 will be described with reference to Fig. 3A to Fig. 7. Here, the deterioration diagnosis flow of sliding parts or parts that come into contact with sliding parts that come into contact with liquid fuel will be described. The sliding parts or parts that come into contact with sliding parts are, for example, intake valves, exhaust valves, intake valve seats, exhaust valve seats, cylinders, pistons, piston rings, etc.

Engine component deterioration diagnosis is performed every specified mileage, for example, every 10,000 km.

First, after the previous engine part deterioration diagnosis is completed, measurement of the vehicle's travel distance L1 to be used in the engine part deterioration diagnosis is started (step S101).

Next, proceed to step S102 and start measuring the vehicle's travel distance L2, which will be used to calculate the average Pmi, as described below.

Next, the process proceeds to step S103, where the alcohol content [%] of the fuel, the Ne-Th state of the engine 20, and the operating time [hr] of the engine 20 are acquired. In this embodiment, the alcohol content acquisition unit 113 acquires the alcohol content of the fuel. The alcohol content acquisition unit 113 acquires the alcohol content of the fuel based on the concentration of alcohol contained in the fuel detected by the concentration sensor 21 of the engine 20. The alcohol content acquisition unit 113 also acquires the Ne-Th state of the engine 20 based on the crankshaft rotation speed Ne detected by the crank pulse sensor 22 of the engine 20 and the throttle opening Th detected by the throttle opening sensor 23 of the engine 20. The engine operating time acquisition unit 114 also acquires the operating time [hr] of the engine 20 from the start of measurement of the travel distance L2.

Then, proceed to step S104 and determine whether the vehicle's travel distance L2 used to calculate the average Pmi is 250 km or more. If the vehicle's travel distance L2 used to calculate the average Pmi is not 250 km or more (step S104: NO), return to step S103 and continue to obtain the alcohol content [%] of the fuel, the Ne-Th state of the engine 20, and the operating time [hr] of the engine 20.

When the vehicle's travel distance L2 used to calculate the average Pmi becomes 250 km or greater (step S104: YES), the process proceeds to step S105.

In step S105, the engine state frequency ratio map creation unit 115a creates an engine state frequency ratio map of crankshaft rotation speed Ne - throttle opening Th based on the crankshaft rotation speed Ne detected by the crank pulse sensor 22 of the engine 20 and the throttle opening Th detected by the throttle opening sensor 23 of the engine 20.

The engine state frequency ratio map is a table with the horizontal axis representing the crankshaft rotation speed Ne [rpm] and the vertical axis representing the throttle opening Th [%], as shown in Figure 4.

The crankshaft rotation speed Ne on the horizontal axis can be, for example, 1500 [rpm] or less, more than 1500 [rpm] and less than 2000 [rpm], more than 2000 [rpm] and less than 2500 [rpm], more than 2500 [rpm] and less than 3000 [rpm], more than 3000 [rpm] and less than 3500 [rpm], more than 3500 [rpm] and less than 4000 [rpm], more than 4000 [rpm] and less than 4500 [rpm], more than 4500 [rpm] and less than 5000 [rpm], more than 5000 [rpm] and less than 5500 [rpm], more than 5500 [rpm] and less than 6000 [rpm], and less than 6000 [rpm]. They are classified as follows: over 6500 rpm, over 6500 rpm and under 7000 rpm, over 7000 rpm and under 7500 rpm, over 7500 rpm and under 8000 rpm, over 8000 rpm and under 8500 rpm, over 8500 rpm and under 9000 rpm, over 9000 rpm and under 9500 rpm, over 9500 rpm and under 10000 rpm, over 10000 rpm and under 10500 rpm, over 10500 rpm and under 11000 rpm, and over 11000 rpm.

The throttle opening degree Th on the vertical axis is classified into, for example, 0%; more than 0% and less than 10%; more than 10% and less than 20%; more than 20% and less than 30%; more than 30% and less than 40%; more than 40% and less than 50%; more than 50% and less than 60%; more than 60% and less than 70%; more than 70% and less than 80%; more than 80% and less than 90%; and more than 90% (less than 100%).

The engine state frequency ratio map is a table in which, for each cell corresponding to the crankshaft rotation speed Ne - throttle opening Th, the ratio of the time the engine 20 was in the corresponding crankshaft rotation speed Ne - throttle opening Th state is recorded, assuming that the driving time of the engine 20 since the completion of the previous engine part deterioration diagnosis is 100. This may be updated at any time while the engine 20 is being driven.

Then, proceed to step S106, and calculate the average alcohol content [%] of the fuel from the alcohol content [%] of the fuel obtained in step S103. The average alcohol content [%] of the fuel is the average value of the alcohol content [%] of the fuel obtained in step S103 from the start of measurement of the vehicle's travel distance L2 used to calculate the average Pmi in step S102.

Then, the process proceeds to step S107, where the indicated mean effective pressure frequency map creation unit 115b selects one indicated mean effective pressure reference map corresponding to the average alcohol content [%] of the fuel calculated in step S106 from among a plurality of indicated mean effective pressure reference maps that have been created in advance in correspondence with the alcohol content of the fuel stored in the indicated mean effective pressure reference map storage unit 111.

Then, proceed to step S108, and in the indicated mean effective pressure frequency map creation unit 115b, a frequency map of the indicated mean effective pressure Pmi is created. Specifically, first, the engine state frequency ratio map created in step S105 and one indicated mean effective pressure reference map selected in step S107 are referenced. Then, the value obtained by multiplying the values of the corresponding cells of each crankshaft rotation speed Ne-throttle opening Th is recorded in each corresponding cell of the crankshaft rotation speed Ne-throttle opening Th. The table created in this way is the indicated mean effective pressure frequency map shown in FIG. 5. Furthermore, in step S108, the average Pmi is calculated from the created indicated mean effective pressure frequency map. Specifically, the sum of the values of all the cells in the created indicated mean effective pressure frequency map is calculated, and the value of the average Pmi is calculated by (the sum of the values of all the cells in the indicated mean effective pressure frequency map)/100.

Then, proceed to step S109, where the time-frequency map creation unit 115c creates a time-frequency map.

The time-frequency map creation unit 115c first refers to the engine 20 drive time [hr] from the start of measurement of the vehicle's travel distance L2 used to calculate the average Pmi in step S102 until the vehicle's travel distance reaches 250 [km] based on the engine 20 drive time [hr] obtained in step S103, and the engine state frequency ratio map created in step S105 from the start of measurement of the vehicle's travel distance L2 used to calculate the average Pmi in step S102 until the vehicle's travel distance reaches 250 [km]. Then, the value obtained by multiplying the engine 20 drive time [hr] obtained in step S103 is recorded in each cell of the crankshaft rotation speed Ne-throttle opening Th in the engine state frequency ratio map. The table created in this way is the time-frequency map shown in FIG. 6.

Then, the process proceeds to step S110, where the cumulative crankshaft revolutions calculation unit 115d calculates the cumulative number of revolutions Rd [ten thousand revolutions] of the crankshaft of the engine 20 from the start of measurement of the vehicle travel distance L2 used to calculate the average Pmi in step S102 until the vehicle travel distance reaches 250 [km].

In the crankshaft cumulative rotation speed calculation unit 115d, first, for each cell of the time-frequency map created in step S109, a value obtained by multiplying the corresponding crankshaft rotation speed Ne [rpm] × 60 is recorded. The corresponding crankshaft rotation speed Ne [rpm] is, for example, 1500 [rpm] for columns of 1500 [rpm] or less, 2000 [rpm] for columns of more than 1500 [rpm] and less than 2000 [rpm], 2500 [rpm] for columns of more than 2000 [rpm] and less than 2500 [rpm], 3000 [rpm] for columns of more than 2500 [rpm] and less than 3000 [rpm], and 3500 [rpm] or less. The column is 3500 [rpm], the column between 3500 [rpm] and 4000 [rpm] is 4000 [rpm], the column between 4000 [rpm] and 4500 [rpm] is 4500 [rpm], the column between 4500 [rpm] and 5000 [rpm] is 5000 [rpm], the column between 5000 [rpm] and 5500 [rpm] is 5500 [rpm], the column between 5500 [rpm] and 6000 [rpm] is 6000 [rpm], 600 The column for 0 [rpm] or more and 6500 [rpm] or less is 6500 [rpm], the column for 6500 [rpm] or more and 7000 [rpm] or less is 7000 [rpm], the column for 7000 [rpm] or more and 7500 [rpm] or less is 7500 [rpm], the column for 7500 [rpm] or more and 8000 [rpm] or less is 8000 [rpm], the column for 8000 [rpm] or more and 8500 [rpm] or less is 8500 [rpm], the column for 8500 [rpm] or more and 9000 [rpm] or less The lower row is 9000 [rpm], the row between 9000 [rpm] and 9500 [rpm] is 9500 [rpm], the row between 9500 [rpm] and 10000 [rpm] is 10000 [rpm], the row between 10000 [rpm] and 10500 [rpm] is 10500 [rpm], the row between 10500 [rpm] and 11000 [rpm] is 11000 [rpm], and the row over 11000 [rpm] is 11500 [rpm]. The table created in this way is the crankshaft rotation speed map shown in Figure 7.

Then, the sum of the values of all the cells in the created crankshaft rotation speed map is calculated. In this way, the cumulative number of rotations Rd [10,000 times] of the crankshaft of the engine 20 until the vehicle travel distance L2 used to calculate the average Pmi in step S102 reaches 250 [km] is calculated.

When steps S105 to S110 are completed, proceed to step S111 and reset the vehicle's travel distance L2 used to calculate the average Pmi in step S102.

Then, proceed to step S112 and determine whether the mileage L1 of the vehicle used in the engine part deterioration diagnosis has reached a predetermined mileage (e.g., 10,000 km). If the mileage L1 of the vehicle used in the engine part deterioration diagnosis has not reached the predetermined mileage (e.g., 10,000 km) (step S112: NO), return to step S102 and repeat the calculation of the average Pmi, the creation of the time frequency map, and the calculation of the cumulative crankshaft rotation number Rd every time the mileage L2 of the vehicle used in the average Pmi calculation reaches 250 km. Then, when the mileage L1 of the vehicle used in the engine part deterioration diagnosis has reached the predetermined mileage (e.g., 10,000 km) (step S112: YES), proceed to step S113.

In step S113, the damage deterioration degree calculation unit 116a estimates the damage deterioration degree [%], which is the degree of deterioration due to damage of the engine part whose deterioration degree is to be estimated.

In step S113, first, the average value of each average Pmi value calculated in step S108 is calculated until the vehicle mileage L1 used in the engine component deterioration diagnosis in step S101 reaches a predetermined mileage (e.g., 10,000 km).

Next, the sum of the cumulative number of rotations Rd [ten thousand times] of each crankshaft calculated in step S110 is calculated until the vehicle mileage L1 used in the engine component deterioration diagnosis in step S101 reaches a predetermined mileage (e.g., 10,000 km).

Then, calculate the damage deterioration value [kPa x 10,000 times] = average value of average Pmi [kPa] x sum of cumulative crankshaft rotation count Rd [10,000 times] x α (wear rate).

Then, the total damage degradation value [kPa x 10,000 times] up to the previous engine part deterioration diagnosis is added to the damage degradation value [kPa x 10,000 times] calculated in the current engine part deterioration diagnosis to calculate the cumulative damage degradation value [kPa x 10,000 times].

Finally, the damage degradation degree [%] = (cumulative damage degradation value [kPa x 10,000 times] x 100) / (damage degradation value of the target engine part requiring replacement [kPa x 10,000 times]). In this way, the damage degradation degree calculation unit 116a estimates the damage degradation degree [%], which is the degree of degradation due to damage of the target engine part whose degradation degree is to be estimated.

Next, the process proceeds to step S114, where the corrosion deterioration degree calculation unit 116b estimates the corrosion deterioration degree [%], which is the degree of deterioration due to corrosion of the engine part whose deterioration degree is to be estimated.

In step S114, the average value of each average Pmi value calculated in step S108 is calculated until the vehicle mileage L1 used in the engine component deterioration diagnosis in step S101 reaches a predetermined mileage (e.g., 10,000 km).

Next, the average value of each average alcohol content [%] of the fuel calculated in step S106 is calculated until the vehicle mileage L1 used in the engine component deterioration diagnosis in step S101 reaches a predetermined mileage (e.g., 10,000 [km]).

Next, the sum of the cumulative number of rotations Rd [ten thousand times] of each crankshaft calculated in step S110 is calculated until the vehicle mileage L1 used in the engine component deterioration diagnosis in step S101 reaches a predetermined mileage (e.g., 10,000 km).

Then, calculate the corrosion deterioration value [kPa x 10,000 times] = (average value of each alcohol content [%] of the fuel / 100) x average value of each average Pmi [kPa] x sum of cumulative crankshaft revolutions Rd [10,000 times] x β (corrosion rate).

Then, the cumulative corrosion deterioration value [kPa x 10,000 times] is calculated by adding the corrosion deterioration value [kPa x 10,000 times] calculated in the current engine part deterioration diagnosis to the total corrosion deterioration value [kPa x 10,000 times] up to the previous engine part deterioration diagnosis.

Finally, the corrosion deterioration degree [%] = (cumulative corrosion deterioration value [kPa x 10,000 times] x 100) / (replacement-requiring corrosion deterioration value of the target engine part [kPa x 10,000 times]). In this way, the corrosion deterioration degree calculation unit 116b estimates the corrosion deterioration degree [%], which is the degree of deterioration due to corrosion of the target engine part whose deterioration degree is to be estimated.

In this way, the damage deterioration degree [%] and corrosion deterioration degree [%] of the engine part whose deterioration degree is to be estimated are estimated based on the indicated mean effective pressure Pmi [kPa] when the engine 20 is running and the cumulative number of rotations Rd [ten thousand times] of the crankshaft.

This makes it possible to accurately estimate the degree of deterioration of not only fuel filters but also various engine parts.

In addition, it is possible to estimate the degree of deterioration of engine parts due to damage and the degree of deterioration due to corrosion, and by estimating either or both of the degree of deterioration due to damage and the degree of deterioration due to corrosion depending on the engine part whose deterioration is to be estimated, the accuracy of estimating the degree of deterioration of the engine parts can be improved.

In particular, as mentioned above, when the engine part for which the deterioration level is to be estimated is in contact with liquid fuel and is a sliding part or a part that is in contact with a sliding part, the deterioration level due to both damage and corrosion is estimated.

This makes it possible to improve the accuracy of estimating the degree of deterioration for engine parts that are significantly affected by both deterioration due to damage and deterioration due to corrosion.

As described above, in steps S103 and S104, the alcohol content of the fuel is obtained each time the vehicle travels a predetermined distance, and in step S107, an average alcohol content is calculated in step S106 from the alcohol content of the fuel obtained in step S103, and one indicated mean effective pressure reference map is selected from among multiple indicated mean effective pressure reference maps that have been created in advance to correspond to the alcohol content of the fuel based on the average alcohol content.

In this way, by creating multiple indicated mean effective pressure reference maps in advance corresponding to the alcohol content of the fuel and selecting the indicated mean effective pressure map corresponding to the alcohol content of the fuel, it is possible to improve the accuracy of estimating the deterioration level of engine parts according to the alcohol content of the fuel used in the engine 20.

Then, the process proceeds to step S115, where the damage degradation value [kPa x 10,000 cycles] and damage degradation degree [%] estimated in step S113 for the target engine part, as well as the corrosion degradation value [kPa x 10,000 cycles] and corrosion degradation degree [%] estimated in step S114 are stored in the engine part condition storage unit 118 as the degradation degree of the target engine part in this engine part degradation diagnosis.

Then, proceed to step S116, and determine whether the damage deterioration degree [%] estimated in step S113 and the corrosion deterioration degree [%] estimated in step S114 of the target engine part are, for example, 80 [%] or more. Note that this determination value is only an example and is not limited to 80 [%] and may be determined according to the concept of safety factor for each part, etc.

If at least one of the damage degradation degree [%] estimated in step S113 and the corrosion degradation degree [%] estimated in step S114 of the target engine part is 80 [%] or more (step S116: YES), proceed to step S117. If both the damage degradation degree [%] estimated in step S113 and the corrosion degradation degree [%] estimated in step S114 of the target engine part are less than 80 [%] (step S116: NO), proceed to step S118.

In step S117, the notification unit 119 issues a notification urging the user to replace the target engine part. For example, the notification unit 119 may be a display panel that displays text information urging the user to replace the target engine part, or the notification unit 119 may be an indicator light such as an LED that turns on when urging the user to replace the target engine part. Then, the process proceeds to step S121.

This will encourage vehicle users to replace engine parts at the appropriate time.

In addition, in the engine part deterioration diagnosis in the engine part deterioration diagnosis device 11, when the deterioration level of multiple engine parts is diagnosed, in step S117, if there are other engine parts that should be replaced at the same time as replacing the engine part for which the notification to promote replacement is sent, the notification unit 119 sends a notification to promote the replacement of the other engine parts.

As a result, when issuing a notification to encourage the replacement of an engine part that requires a large amount of labor, it is possible to issue a notification to encourage the replacement of surrounding engine parts that are desirable to replace at the same time as the replacement of the engine part, thereby reducing the labor and costs required for replacement compared to replacing these engine parts separately.

In step S118, it is determined whether the damage deterioration degree [%] of the target engine part estimated in step S113 is equal to or greater than the corrosion deterioration degree [%] estimated in step S114.

In general, the lower the alcohol content of the fuel, the greater the degree of deterioration due to damage, and the higher the alcohol content of the fuel, the greater the degree of deterioration due to corrosion.

Therefore, if the damage deterioration degree [%] of the target engine part estimated in step S113 is equal to or greater than the corrosion deterioration degree [%] estimated in step S114 (step S113: YES), it is estimated that the optimal fuel is a fuel with a high alcohol content. Then, the process proceeds to step S119, and the notification unit 119 issues a notification that the use of a fuel with a high alcohol content is recommended. For example, the notification unit 119 may be a display panel that displays text information indicating that the use of a fuel with a high alcohol content is recommended, or the notification unit 119 may be an indicator light such as an LED that turns on when the use of a fuel with a high alcohol content is recommended. Then, the process proceeds to step S121.

On the other hand, if the damage deterioration degree [%] of the target engine part estimated in step S113 is less than the corrosion deterioration degree [%] estimated in step S114 (step S113: NO), it is estimated that the optimal fuel is a fuel with a low alcohol content. Therefore, the process proceeds to step S120, and the notification unit 119 issues a notification that the use of a fuel with a low alcohol content is recommended. For example, the notification unit 119 may be a display panel that displays text information indicating that the use of a fuel with a low alcohol content is recommended, or the notification unit 119 may be an indicator light such as an LED that turns on when the use of a fuel with a low alcohol content is recommended. Then, the process proceeds to step S121.

In this way, the notification unit 119 notifies information indicating the optimal fuel based on at least one of the damage deterioration degree [%] estimated in step S113 and the corrosion deterioration degree [%] estimated in step S114 of the target engine part.

By recommending the use of fuel with a desirable alcohol content in terms of engine part deterioration, the timing at which engine parts need to be replaced can be delayed, allowing engine parts to be used for a longer period of time. Using engine parts for a longer period of time also reduces carbon dioxide emissions during the manufacture/disposal of engine parts, which is desirable from a carbon neutral perspective.

This completes one engine part deterioration diagnosis, resets the vehicle's travel distance L1 used in the engine part deterioration diagnosis in step S101 (step S121), and returns to step S101.

<Vehicle value assessment device>
Returning to FIG. 1 , the engine part deterioration diagnosis system 10 further includes a vehicle value assessment device 12 that assesses the value of the vehicle based on the deterioration degree of the engine parts estimated by the engine part deterioration diagnosis device 11. The vehicle value assessment device 12 may be mounted on the vehicle in which the engine 20 is mounted, or may be provided outside the vehicle in which the engine 20 is mounted. The vehicle value assessment device 12 may be installed, for example, in a vehicle dealer or a vehicle repair shop, or may be a management server installed by a vehicle manufacturer to manage multiple vehicles manufactured by the manufacturer. In this embodiment, the vehicle value assessment device 12 is provided outside the vehicle in which the engine 20 is mounted. The engine part deterioration diagnosis device 11 and the vehicle value assessment device 12 are capable of mutual data communication by wireless communication or a detachable cable or the like.

The vehicle value assessment device 12 assesses the value of the vehicle based on the degree of deterioration of one or more engine parts estimated by the engine part deterioration diagnosis device 11.

The vehicle value assessment device 12 acquires the latest damage deterioration degree [%] and corrosion deterioration degree [%] of each engine part stored in the engine part condition memory unit 118 of the engine part deterioration diagnosis device 11. The vehicle value assessment device 12 then assesses the current value of the vehicle based on the acquired latest damage deterioration degree [%] and corrosion deterioration degree [%] of each engine part. For example, if deteriorated engine parts are replaced periodically and the latest damage deterioration degree [%] and corrosion deterioration degree [%] of each engine part are low, the vehicle value is assessed to be high.

This allows for a more rational assessment of the vehicle's value, taking into account the degree of deterioration of each engine part.

The vehicle value assessment device 12 also acquires the trends in the damage degradation degree [%] and corrosion degradation degree [%] of each engine part in multiple engine part degradation diagnoses performed up to the present time by the engine part degradation diagnosis device 11, which are stored in the engine part condition memory unit 118 of the engine part degradation diagnosis device 11.The vehicle value assessment device 12 then predicts the future trends in the value of the vehicle based on the acquired trends in the damage degradation degree [%] and corrosion degradation degree [%] of each engine part up to the present time and the assessment result of the value of the vehicle at the present time.

This allows vehicle users to predict a more appropriate time to sell their vehicle when considering selling it in the future, based on the trends in the damage deterioration degree [%] and corrosion deterioration degree [%] of engine parts.

The vehicle value assessment device 12 may be capable of simulating the value of the vehicle when a specific engine part is replaced, based on the latest damage deterioration degree [%] and corrosion deterioration degree [%] of each engine part, and/or the progress of the damage deterioration degree [%] and corrosion deterioration degree [%] of each engine part in multiple engine part deterioration diagnoses performed up to the present time.

This allows the vehicle user to decide whether or not to replace a particular engine part based on the change in the vehicle's value when that part is replaced.

Although one embodiment of the present invention has been described above with reference to the attached drawings, it goes without saying that the present invention is not limited to such an embodiment. It is clear that a person skilled in the art can come up with various modified or revised examples within the scope of the claims, and it is understood that these also naturally fall within the technical scope of the present invention. Furthermore, the components in the above embodiment may be combined in any manner as long as it does not deviate from the spirit of the invention.

For example, in this embodiment, the deterioration diagnosis flow for sliding parts or parts that come into contact with liquid fuel and are in contact with sliding parts has been described. However, for parts that come into contact with liquid fuel but are not sliding parts or parts that come into contact with sliding parts, such as oil seals, gaskets, and packings, only the deterioration level due to corrosion (corrosion deterioration level) may be estimated, and for parts that do not come into contact with gaseous fuel and are sliding parts or parts that come into contact with sliding parts, such as crankshafts, connecting rods, and bearing parts, only the deterioration level due to damage (damage deterioration level) may be estimated.

For example, in this embodiment, the engine part deterioration diagnosis device 11 is mounted on a vehicle equipped with the engine 20, but it does not have to be mounted on the vehicle. The engine part deterioration diagnosis device 11 may be located on a cloud server, for example, or part of it may be located on the cloud server and another part may be located on the vehicle.

In addition, for example, in this embodiment, engine part deterioration diagnosis is performed every 10,000 km, but engine part deterioration diagnosis may be performed every specified mileage.

In addition, for example, in this embodiment, in step S102, measurement of the vehicle's travel distance L2 used to calculate the average Pmi is started, and in step S104, it is determined whether the vehicle's travel distance L2 used to calculate the average Pmi in step S102 is 250 km or more. However, it may be a predetermined travel distance other than 250 km, and steps S105 to S110 may be executed each time the user fills the vehicle with fuel. For example, a lid sensor or the like may be attached to the vehicle, and it may be determined whether the user has filled the vehicle with fuel based on detection information from the lid sensor.

In addition, in this embodiment, the degree of damage deterioration and the degree of corrosion deterioration are estimated based on the cumulative rotation speed Rd of the crankshaft, but the degree of damage deterioration and the degree of corrosion deterioration may also be estimated based on the cumulative rotation speed of any rotating part other than the crankshaft that constitutes the engine 20, such as a camshaft.

This specification describes at least the following items. In parentheses, examples of corresponding components in the above-mentioned embodiments are shown, but the present invention is not limited to these.

(1) An engine component deterioration diagnosis system (engine component deterioration diagnosis system 10) that estimates a deterioration level of at least one of a plurality of engine components that constitute an engine (engine 20) that is mounted on a vehicle and generates driving force by burning a fuel containing gasoline and alcohol, comprising:
one of the plurality of engine components is a rotating component;
An indicated mean effective pressure (indicated mean effective pressure Pmi) when the engine is running;
The cumulative rotation speed of the rotating part (the cumulative rotation speed Rd of the crankshaft);
and estimating a degree of deterioration of at least one of the plurality of engine parts based on the above.

(1) makes it possible to accurately estimate the degree of deterioration of not only fuel filters but also various engine parts.

(2) The engine part deterioration diagnosis system according to (1),
a plurality of indicated mean effective pressure reference maps prepared in advance in accordance with the alcohol content of the fuel;
acquiring an alcohol content of the fuel every time the vehicle travels a predetermined distance;
an engine component deterioration diagnosis system that selects one of the plurality of indicated mean effective pressure reference maps based on the obtained alcohol content of the fuel;

According to (2), by creating multiple indicated mean effective pressure reference maps in advance corresponding to the alcohol content of the fuel and selecting the map of indicated mean effective pressure corresponding to the alcohol content of the fuel, it is possible to improve the accuracy of estimating the deterioration degree of engine parts according to the alcohol content of the fuel used in the engine 20.

(3) The engine part deterioration diagnosis system according to (1) or (2),
The deterioration degree due to damage and the deterioration degree due to corrosion of the engine part can be estimated,
An engine part deterioration diagnosis system that estimates one or both of the degree of deterioration due to damage and the degree of deterioration due to corrosion depending on the engine part whose deterioration degree is to be estimated.

According to (3), it is possible to estimate the degree of deterioration of an engine part due to damage and the degree of deterioration due to corrosion. By estimating either or both of the degree of deterioration due to damage and the degree of deterioration due to corrosion depending on the engine part whose deterioration is to be estimated, it is possible to improve the accuracy of estimating the degree of deterioration of the engine part.

(4) The engine part deterioration diagnosis system according to (3),
In the case where the engine part whose deterioration degree is to be estimated is in contact with the fuel in a liquid state and is a sliding part or a part that is in contact with a sliding part,
An engine part deterioration diagnosis system that estimates both the degree of deterioration due to the damage and the degree of deterioration due to the corrosion.

(4) The accuracy of estimating the degree of deterioration can be improved for engine parts that are significantly affected by both deterioration due to damage and deterioration due to corrosion.

(5) The engine part deterioration diagnosis system according to (3),
An engine part deterioration diagnosis system that estimates the optimum fuel based on at least one of the degree of deterioration due to damage and the degree of deterioration due to corrosion.

(5) By using this method, the timing at which engine parts need to be replaced can be delayed, allowing the engine parts to be used for a longer period of time.

(6) The engine part deterioration diagnosis system according to (1),
When the degree of deterioration of the engine part is equal to or greater than a predetermined value, a notification is given to urge the replacement of the engine part.

(6) According to this, vehicle users can be encouraged to replace engine parts at the appropriate time.

(7) The engine part deterioration diagnosis system according to (6),
An engine part deterioration diagnosis system that, when there are other engine parts that should be replaced at the same time as replacing an engine part whose deterioration level is equal to or higher than a predetermined value, issues a notification to encourage the replacement of the other engine parts.

According to (7), when a notification is given to encourage the replacement of an engine part that requires a large amount of labor to replace, a notification can be given to encourage the replacement of surrounding engine parts that are desirable to replace at the same time as the replacement of the engine part, thereby reducing the labor and costs required for replacement compared to replacing these engine parts separately.

(8) The engine part deterioration diagnosis system according to (1),
an engine part deterioration diagnosis device (engine part deterioration diagnosis device 11) that estimates a deterioration degree of at least one of the plurality of engine parts that configure the engine;
a vehicle value assessment device (vehicle value assessment device 12) that assesses the value of the vehicle based on the degree of deterioration of the engine parts estimated by the engine part deterioration diagnosis device.

According to (8), the value of a vehicle can be assessed more rationally by taking into account the degree of deterioration of engine parts.

(9) The engine part deterioration diagnosis system according to (8),
The vehicle value assessment device is an engine part deterioration diagnosis system that predicts the future changes in the value of the vehicle based on the changes in the degree of deterioration of the engine parts up to the present time estimated by the engine part deterioration diagnosis device and the assessment result of the value of the vehicle at the present time.

According to (9), a vehicle user can predict a more appropriate timing for selling the vehicle when considering selling the vehicle in the future, based on the progression of the deterioration degree of engine parts.

10 Engine part deterioration diagnosis system 11 Engine part deterioration diagnosis device 12 Vehicle value assessment device 20 Engine Pmi Indicated mean effective pressure Rd Accumulative number of revolutions of crankshaft

Claims (9)

An engine component deterioration diagnosis system (10) that estimates a deterioration degree of at least one of a plurality of engine components constituting an engine (20) that is mounted on a vehicle and generates driving force by burning a fuel containing gasoline and alcohol, comprising:
one of the plurality of engine components is a rotating component;
An indicated mean effective pressure (Pmi) when the engine (20) is operating; and
The cumulative number of revolutions (Rd) of the rotating part; and
and estimating a degree of deterioration of at least one of the plurality of engine parts based on the above. 2. An engine component deterioration diagnosis system (10) according to claim 1,
a plurality of indicated mean effective pressure reference maps prepared in advance in accordance with the alcohol content of the fuel;
acquiring an alcohol content of the fuel every time the vehicle travels a predetermined distance;
An engine component deterioration diagnosis system (10) that selects one of the plurality of indicated mean effective pressure reference maps based on the obtained alcohol content of the fuel. 3. An engine component deterioration diagnosis system (10) according to claim 1 or 2,
The deterioration degree due to damage and the deterioration degree due to corrosion of the engine part can be estimated,
An engine part degradation diagnosis system (10) that estimates one or both of the degree of degradation due to damage and the degree of degradation due to corrosion depending on the engine part whose degree of degradation is to be estimated. 4. An engine component deterioration diagnosis system (10) according to claim 3,
In the case where the engine part whose deterioration degree is to be estimated is in contact with the fuel in a liquid state and is a sliding part or a part that is in contact with a sliding part,
An engine part deterioration diagnosis system (10) that estimates both the degree of deterioration due to the damage and the degree of deterioration due to the corrosion. 4. An engine component deterioration diagnosis system (10) according to claim 3,
An engine part deterioration diagnosis system (10) that estimates the optimum fuel based on at least one of the degree of deterioration due to damage and the degree of deterioration due to corrosion. 2. An engine component deterioration diagnosis system (10) according to claim 1,
When the deterioration level of the engine part is equal to or higher than a predetermined value, a notification is given to urge the user to replace the engine part. 7. An engine component deterioration diagnosis system (10) according to claim 6, comprising:
The engine part deterioration diagnosis system (10) provides a notification to encourage the replacement of other engine parts when there are other engine parts that should be replaced at the same time as replacing the engine part whose deterioration level is equal to or higher than a predetermined value. 2. An engine component deterioration diagnosis system (10) according to claim 1,
an engine part deterioration diagnosis device (11) for estimating a deterioration degree of at least one of the plurality of engine parts constituting the engine;
and a vehicle value assessment device (12) that assesses the value of the vehicle based on the degree of deterioration of the engine parts estimated by the engine part deterioration diagnosis device. 9. An engine component deterioration diagnosis system (10) according to claim 8, comprising:
The vehicle value assessment device (12) is an engine part deterioration diagnosis system (10) that predicts the future change in value of the vehicle based on the change in the degree of deterioration of the engine parts up to the present time estimated by the engine part deterioration diagnosis device (11) and the assessment result of the value of the vehicle at the present time.

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