Engine equipment

Abstract

To confirm that fuel dilution has been resolved after oil replacement.SOLUTION: An engine device includes an engine having a cylinder injection valve and a control device that controls the engine. The control device makes a dilution resolution determination on whether dilution of oil with fuel has been resolved on the basis of a learning value in air-fuel ratio learning and a correction value in feedback control of an air-fuel ratio when a request for resetting a dilution estimation value of the oil with the fuel based on oil replacement is made, and resets the dilution estimation value when determining that the dilution has been resolved.SELECTED DRAWING: Figure 3

Description

[Technical Field]

[0001] The present disclosure relates to an engine device, and more particularly to an engine device including an engine having a direct injection valve and a control device that controls the engine. [Background technology]

[0002] Conventionally, one proposed engine device of this type is one that performs a process to regenerate a gasoline particulate filter (GPF) attached to the engine's exhaust system when the amount of accumulated particulates in the GPF increases (see, for example, Patent Document 1). In this device, when regenerating the GPF, combustion of the air-fuel mixture in some of the cylinders is stopped, and when the air-fuel mixture is burned in the other cylinders, a temperature increase process is performed to remove particulates (PM) accumulated in the GPF by making the air-fuel ratio richer than the stoichiometric air-fuel ratio. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Publication No. 2022-076163 Summary of the Invention [Problem to be solved by the invention]

[0004] In an engine with a direct injection valve, if the engine is frequently stopped before warming up, the amount of fuel diluted in the oil increases, which may result in prohibiting intermittent engine operation or prohibiting the GPF heating process described above. When the oil is changed, the dilution of the oil with fuel is eliminated and the prohibition on the GPF heating process is lifted. However, if the oil is not changed correctly, the GPF may overheat if the prohibition on the GPF heating process is lifted and the heating process is performed even though the dilution of the oil with fuel has not been eliminated.

[0005] The engine system of the present disclosure is primarily intended to ensure that fuel dilution is eliminated after an oil change. [Means for solving the problem]

[0006] The engine device of the present disclosure employs the following measures to achieve the above-mentioned main object.

[0007] The engine device of the present disclosure comprises: An engine device including an engine having an in-cylinder injection valve and a control device that controls the engine, When a request for resetting an estimated value of oil dilution by fuel is made based on an oil change, the control device determines whether or not dilution by fuel has been eliminated based on a learned value in air-fuel ratio learning and / or a correction value in feedback control of the air-fuel ratio, and resets the estimated value of dilution when it is determined that dilution has been eliminated. It is characterized by:

[0008] In the engine system of the present disclosure, when a request to reset the estimated oil dilution value due to an oil change is made, a dilution elimination determination is made to determine whether the oil dilution has been eliminated based on the learned value in the air-fuel ratio learning and the correction value in the air-fuel ratio feedback control. This makes it possible to confirm that the fuel dilution has been eliminated after the oil change. If it is determined that the dilution has been eliminated, the dilution estimate value is reset. This allows the dilution estimate value to be reset more appropriately.

[0009] In the engine system of the present disclosure, when there is a history of air-fuel ratio learning for a high intake air volume region of the engine operating range, the control device may perform the dilution elimination determination based on the difference between the sum of the learned value of the air-fuel ratio learning for a low intake air volume region, where the intake air volume is relatively small, and the feedback control correction value, and the learned value of the air-fuel ratio learning for the high intake air volume region in the history. In the high intake air volume region, the influence of fuel dilution is small, so the learned value of the air-fuel ratio learning does not change much depending on whether fuel dilution has been eliminated. On the other hand, in the low intake air volume region, the influence of fuel dilution is large, so the learned value of the air-fuel ratio learning changes significantly depending on whether fuel dilution has been eliminated. Therefore, it is possible to determine that fuel dilution has been eliminated when the sum of the learned value of the air-fuel ratio learning for the low intake air volume region and the feedback control correction value minus the learned value of the air-fuel ratio learning for the high intake air volume region is equal to or greater than a threshold value, and to determine that fuel dilution has not been eliminated when the sum is less than the threshold value. In such an engine system, when there is no history of air-fuel ratio learning for the high intake air volume region, the control device may make the dilution elimination determination based on the learned value of air-fuel ratio learning for a low intake air volume region where the intake air volume is relatively small and the correction value. Since the sum of the learned value of air-fuel ratio learning for the low intake air volume region and the correction value corresponds to the actual air-fuel ratio, it is possible to determine whether fuel dilution has been eliminated by comparing the actual air-fuel ratio with a threshold value.

[0010] In the engine system of the present disclosure, the reset request may be made based on the dealer's switch operation for an oil change or the reset operation for the mileage after the oil change, and the dilution elimination determination when the reset request is made based on the switch operation and the dilution elimination determination when the reset request is made based on the reset operation may use different threshold values. For example, if the dilution elimination determination is made based on the difference between the learned value of the air-fuel ratio for the high intake air volume region and the learned value of the air-fuel ratio for the low intake air volume region, different values ​​or the same value may be used as the threshold value to be compared with the difference. In this way, the fuel dilution determination can be made based on the cause of the reset request.

[0011] In the engine system of the present disclosure, when the control device determines that the dilution has not been eliminated to a certain extent in the dilution elimination determination, the control device may extend the period of the dilution elimination determination until the cumulative intake air volume after starting the engine reaches a predetermined air volume, thereby making it possible to more accurately determine whether the fuel dilution has been eliminated. [Brief explanation of the drawings]

[0012] [Figure 1] 1 is a diagram showing an outline of the configuration of a hybrid vehicle 20 equipped with an engine device according to an embodiment of the present disclosure. [Figure 2] 1 is a diagram showing the outline of the configuration of an engine 22 mounted on a hybrid vehicle 20. FIG. [Figure 3] 4 is a flowchart showing an example of a fuel dilution amount reset process executed by the engine ECU 24. DETAILED DESCRIPTION OF THE INVENTION

[0013] Next, an embodiment of the present disclosure will be described. Fig. 1 is a configuration diagram showing an outline of the configuration of a hybrid vehicle 20 equipped with an engine device according to an embodiment of the present disclosure. Fig. 2 is a configuration diagram showing an outline of the configuration of an engine 22 equipped in the hybrid vehicle 20. The hybrid vehicle 20 of the embodiment includes the engine 22, a motor 30, an inverter 32, a clutch K0, an automatic transmission 40, and a hybrid electronic control unit (hereinafter referred to as "HVECU") 70.

[0014] The engine 22 is a six-cylinder internal combustion engine fueled by gasoline. As shown in Fig. 2, the engine 22 has a port injection valve 126 that injects fuel into an intake port and an in-cylinder injection valve 127 that injects fuel into a cylinder. The engine 22 operates in one of a port injection mode, an in-cylinder injection mode, and a combined injection mode. In the port injection mode, air from an air cleaner 122 is drawn into an intake pipe 123 and passes through a throttle valve 124 and a surge tank 125. Fuel is injected from a port injection valve 126 downstream of the surge tank 125 into the intake pipe 123, mixing the air and fuel. The air-fuel mixture is drawn into a combustion chamber 129 via an intake valve 128 and combusted by an electric spark generated by a spark plug 130. The resulting energy pushes down a piston 132 in the cylinder bore, and the resulting reciprocating motion of the piston 132 is converted into rotational motion of the crankshaft 23. In the direct injection mode, air is drawn into the combustion chamber 129, and fuel is injected from the direct injection valve 127 during the intake stroke or compression stroke. The fuel is then explosively combusted by an electric spark from the spark plug 130, generating rotational motion of the crankshaft 23. In the shared injection mode, fuel is injected from both the port injection valve 126 and the direct injection valve 127. Exhaust gas discharged from the combustion chamber 129 into an exhaust pipe 134 via an exhaust valve 133 is then discharged via a purification device 135 and a gasoline particulate filter (hereinafter referred to as "GPF") 136. The purification device 135 has a purification catalyst (three-way catalyst) 135a that purifies harmful components in the exhaust, such as carbon monoxide (CO), hydrocarbons (HC), and nitrogen oxides (NOx). The GPF 136 is formed as a porous filter made of ceramics, stainless steel, or the like, and captures particulate matter (PM) such as soot in the exhaust. Instead of the GPF 136, a four-way catalyst that combines the purification function of a three-way catalyst with the function of trapping particulate matter may be used.

[0015] The operation of the engine 22 is controlled by an engine electronic control unit (hereinafter referred to as "engine ECU") 24. The engine ECU 24 receives, for example, a crank angle θcr from a crank position sensor 140 that detects the rotational position of a crankshaft 23 of the engine 22, and a coolant temperature Tw from a water temperature sensor 142 that detects the temperature of the coolant for the engine 22. The engine ECU 24 also receives as inputs the following: cam angles θci and θco from a cam position sensor 144 that detects the rotational position of an intake camshaft that opens and closes the intake valve 128 and the rotational position of an exhaust camshaft that opens and closes the exhaust valve 133; a throttle opening TH from a throttle valve position sensor 124a that detects the position of the throttle valve 124; an intake air amount Qa from an air flow meter 123a attached to the intake pipe 123 upstream of the throttle valve 124; an intake air temperature Ta from a temperature sensor 123t attached to the intake pipe 123 upstream of the throttle valve 124; and a surge pressure Ps from a pressure sensor 125a attached to a surge tank 125. Furthermore, the engine ECU 24 also receives input of a front air-fuel ratio AF1 from a front air-fuel ratio sensor 137 attached upstream of the purification device 135 in the exhaust pipe 134, a rear air-fuel ratio AF2 from a rear air-fuel ratio sensor 138 attached between the purification device 135 in the exhaust pipe 134 and the GPF 136, and a differential pressure ΔP from a differential pressure sensor 136a that detects the differential pressure before and after the GPF 136 (the differential pressure between the upstream side and the downstream side).

[0016] The engine ECU 24 outputs, for example, a control signal to a throttle valve 124, a control signal to a port injection valve 126, a control signal to an in-cylinder injection valve 127, a control signal to an ignition plug 130, and the like.

[0017] The engine ECU 24 calculates the rotation speed Ne of the engine 22 based on the crank angle θcr of the engine 22 from the crank position sensor 140. The engine ECU 24 also calculates a load factor KL (the ratio of the volume of air actually taken in per cycle to the stroke volume per cycle of the engine 22) based on the intake air amount Qa from the air flow meter 123a and the rotation speed Ne of the engine 22. The engine ECU 24 also calculates a PM accumulation amount Qpm as the accumulation amount of particulate matter accumulated in the GPF 136 based on the differential pressure ΔP from the differential pressure sensor 136a, and calculates a filter temperature tf as the temperature of the GPF 136 based on the rotation speed Ne of the engine 22 and the load factor KL. The engine ECU 24 also calculates a fuel dilution amount Fd as an estimate of the amount of dilution of oil, which serves as lubricating oil for the engine 22, with fuel based on the coolant temperature Tw at the start of the engine 22 and the integrated value of the intake air amount until the coolant temperature Tw reaches 40°C after start-up. The fuel dilution amount Fd increases when the engine 22 is frequently stopped before warm-up is complete.

[0018] 1, a starter motor 25 for cranking the engine 22 and an alternator 26 for generating electricity using power from the engine 22 are connected to the crankshaft 23 of the engine 22. The starter motor 25 and the alternator 26 are connected to a low-voltage power line 63 together with a low-voltage battery 62, and are controlled by the HVECU 70.

[0019] The motor 30 is configured as a synchronous generator motor. A rotating shaft 31, to which the rotor of the motor 30 is fixed, is connected to the crankshaft 23 of the engine 22 via a clutch K0 and to an input shaft 41 of an automatic transmission 45. The inverter 32 is used to drive the motor 30 and is connected to a high-voltage power line 61. The motor 30 is driven to rotate by a motor electronic control unit (hereinafter referred to as the "motor ECU") 34 controlling the switching of multiple switching elements of the inverter 32. The motor ECU 34 receives inputs such as a rotational position θmg from a rotational position sensor 30a that detects the rotational position of the rotor (rotating shaft 31) of the motor 30 and phase currents Iu and Iv from current sensors that detect the phase currents of each phase of the motor 30, and outputs control signals to the inverter 32. The motor ECU 34 calculates the rotational speed Nmg of the motor 30 based on the rotational position θmg of the rotor (rotating shaft 31) of the motor 30 from the rotational position sensor 30a.

[0020] The clutch K0 is configured as, for example, a hydraulically driven friction clutch, and is controlled by the HVECU 70 to connect and disconnect the crankshaft 23 of the engine 22 and the rotary shaft 31 of the motor 30.

[0021] The automatic transmission 40 includes a torque converter 43 and, for example, a six-speed automatic transmission 45. The torque converter 43 is configured as a typical fluid power transmission device and amplifies the torque of the power of an input shaft 41 connected to the rotary shaft 31 of the motor 30 and transmits it to a transmission input shaft 44, which is the input shaft of the automatic transmission 45, or transmits the torque directly without amplifying it. The automatic transmission 45 includes the transmission input shaft 44, an output shaft 42 connected to drive wheels 49 via a differential gear 48, multiple planetary gears, and multiple hydraulically driven friction engagement elements (clutches, brakes). The automatic transmission 45 establishes forward gears (first through sixth gears) and reverse gears by engaging and disengaging the multiple friction engagement elements, and transmits power between the transmission input shaft 44 and the output shaft 42. The clutch K0 and the automatic transmission 45 are supplied with hydraulic oil from a mechanical oil pump or an electric oil pump after the hydraulic pressure is adjusted by a hydraulic control device (not shown).

[0022] High-voltage battery 60 is configured as, for example, a lithium-ion secondary battery or a nickel-metal hydride secondary battery with a rated voltage of several hundred volts, and is connected to high-voltage power line 61 together with inverter 32. Low-voltage battery 62 is configured as, for example, a lead-acid battery with a rated voltage of about 12 V or 14 V, and is connected to low-voltage power line 63 together with starter motor 25 and alternator 26. DC / DC converter 64 is connected to high-voltage power line 61 and low-voltage power line 63. DC / DC converter 64 supplies power from high-voltage power line 61 to low-voltage power line 63 while stepping down the voltage.

[0023] The HVECU 70 is configured as a microcomputer. The HVECU 70 receives, for example, an engine speed Nin from an engine speed sensor 41a attached to the input shaft 41 of the automatic transmission 40, an engine speed Nmi from an engine speed sensor 44a attached to the transmission input shaft 44 of the automatic transmission 40, and an engine speed Nout from an engine speed sensor 42a attached to the output shaft 42 of the automatic transmission 40. The HVECU 70 also receives, as inputs, a voltage Vbh of the high-voltage battery 60 from a voltage sensor attached between the terminals of the high-voltage battery 60, a current Ibh of the high-voltage battery 60 from a current sensor attached to the output terminal of the high-voltage battery 60, and a voltage Vbl from a voltage sensor attached between the terminals of the low-voltage battery 62. Furthermore, the HVECU 70 also receives as input an ignition signal from an ignition switch 80, a shift position SP from a shift position sensor 82 that detects the operating position of a shift lever 81, an accelerator opening Acc from an accelerator pedal position sensor 84 that detects the amount of depression of an accelerator pedal 83, a brake pedal position BP from a brake pedal position sensor 86 that detects the amount of depression of a brake pedal 85, and a vehicle speed V from a vehicle speed sensor 87.

[0024] The HVECU 70 outputs a control signal to the starter motor 25, a control signal to the alternator 26, a control signal to the clutch K0 and the automatic transmission 40 (hydraulic control device), a control signal to the DC / DC converter 64, etc. The HVECU 70 communicates with the engine ECU 24 and the motor ECU 34. The HVECU 70 calculates a rotation speed ratio Gt of the automatic transmission 40 by dividing the rotation speed Nin of the input shaft 41 of the automatic transmission 40 from the rotation speed sensor 41a by the rotation speed Nout of the output shaft 42 of the automatic transmission 40 from the rotation speed sensor 42a.

[0025] Next, the operation of the engine device mounted on the hybrid vehicle 20 of this embodiment will be described, particularly the operation when resetting the fuel dilution amount Fd, which is an estimated value of the amount of oil diluted by fuel. FIG. 3 is a flowchart illustrating an example of the fuel dilution amount reset process executed by the engine ECU 24. This process is executed when the engine 22 is started after a request to reset the fuel dilution amount Fd is made. The reset request is made when the dealer sets a reset request flag Fr when an oil change is performed at a dealer. The reset request is also made when the user inputs information into the oil mileage system. The oil mileage system notifies the user to change the oil when the mileage since the oil change reaches a predetermined distance, and the user responds to this notification by inputting that the oil has been changed. Therefore, the reason the fuel dilution amount reset process is executed after an oil change is because the oil dilution by fuel is eliminated by the oil change.

[0026] When the fuel dilution amount reset process is executed, the engine ECU 24 first determines whether the reset request for the fuel dilution amount Fd is from the dealer or due to oil mileage (step S100). If the reset request is from the dealer, the threshold value AFref1 is set to a value A11 and the threshold value AFref2 is set to a value A12 (step S110). If the reset request is due to oil mileage, the threshold value AFref1 is set to a value A21 that is slightly larger than the value A11 and the threshold value AFref2 is set to a value A22 that is larger than the value A12 (step S120). The threshold values ​​AFref1 and AFref2 are threshold values ​​used in the dilution cancellation determination, which will be described later.

[0027] Next, the engine 22 is continuously operated in a low intake air volume range (low GA) for a certain period of time (step S130), and purge cut is performed (step S140). The low intake air volume range is a relatively low-speed, low-load operating range of the engine 22. The certain period of time is a period during which the oil temperature is above a predetermined temperature (e.g., 40°C or 45°C) and the integrated value ΣQa of the intake air volume Qa since the start of the engine 22 is above a predetermined value (the amount of air required for the oil temperature to reach the predetermined temperature under normal conditions). The reason for continuously operating the engine 22 in the low intake air volume range (low GA) for a certain period of time is to volatilize the diluted fuel even if the oil change is insufficient. The reason for operating the engine 22 in the low intake air volume range is that the influence of oil dilution by fuel is significant in this range.

[0028] Then, after waiting for the completion of the air-fuel ratio learning in the low intake air volume region (step S150), a dilution cancellation determination (steps S160 to S220) is made. The dilution cancellation determination first determines whether or not there is a history of air-fuel ratio learning in the high intake air volume region (step S160). The high intake air volume region is a region of the engine 22 that operates at a relatively high speed and with a high load. If it is determined that there is a history of air-fuel ratio learning in the high intake air volume region, a learned value AF1 of the air-fuel ratio learning in the high intake air volume region, a learned value AF2 of the air-fuel ratio learning in the low intake air volume region, and a correction value k in the air-fuel ratio feedback control are input (step S180), and it is determined whether or not the sum of the learned value AF2 and the correction value k minus the learned value AF1 is equal to or greater than a threshold value AFref1 (step S180). In the high intake air volume region, the effect of oil dilution by fuel is small, so the learned value AF1 is approximately the same regardless of whether or not there is oil dilution by fuel. On the other hand, in the low intake air volume region, the influence of oil dilution by fuel is large, so the learned value AF2 varies greatly depending on whether or not the oil is diluted by fuel. Therefore, when the oil change is performed properly, the learned value AF2 of the air-fuel ratio learning in the low intake air volume region will be similar to the learned value AF1 of the air-fuel ratio learning in the high intake air volume region, so the sum of the learned value AF2 and the correction value k minus the learned value AF1 ((AF2+k)-AF1) will be a large value. On the other hand, when the oil change is not performed properly, the learned value AF2 of the air-fuel ratio learning in the low intake air volume region will be a different value from the learned value AF1 of the air-fuel ratio learning in the high intake air volume region, so the sum of the learned value AF2 and the correction value k minus the learned value AF1 ((AF2+k)-AF1) will be a small value. Therefore, the elimination of oil dilution by fuel can be determined based on whether the sum of the learned value AF2 and the correction value k minus the learned value AF1 ((AF2+k)-AF1) is large or small. The threshold value AFref1 set in steps S100 to S120 is used to determine whether dilution has been eliminated. When the reset request is made by a dealer, it can be assumed that the oil change is performed more appropriately than when the oil change is made by a user, so the threshold value AFref1 can be set to a smaller value than when the reset request is made by oil mileage.In the embodiment, the value A11 is smaller than the value A21, but the values ​​A11 and A21 may be the same value. In step S180, it is determined whether the difference between the sum of the learned value AF2 and the correction value k and the learned value AF1 minus the learned value AFref1 is equal to or greater than the threshold value AFref1, but it may also be determined whether the difference between the learned value AF2 minus the learned value AF1 is equal to or greater than the threshold value.

[0029] If it is determined in step S180 that the sum of the learned value AF2 and the correction value k minus the learned value AF1 is equal to or greater than the threshold value AFref1, the fuel dilution amount Fd is reset to 0, and the air-fuel ratio learning history is cleared (step S230), and this process ends.

[0030] If it is determined in step S180 that the sum of the learned value AF2 and the correction value k minus the learned value AF1 is less than the threshold value AFref1, it is then determined whether the sum of the learned value AF2 and the correction value k minus the learned value AF1, and then further subtract the threshold value AFref1 from that, ({(AF2+k)-AF1}-AFref1) is equal to or greater than the threshold value Aref (step S190). This determination determines whether the sum of the learned value AF2 and the correction value k minus the learned value AF1 is slightly less than the threshold value AFref1, and therefore whether dilution elimination was slightly prevented. Therefore, a relatively small value can be used as the threshold value Aref. If it is determined that dilution elimination has not been achieved by a small amount, a dilution elimination determination is performed based on the sum of the learned value AF2 of the air-fuel ratio learning for the low intake air volume region and the correction value k in steps S150 to S200, minus the learned value AF1 of the air-fuel ratio learning for the high intake air volume region, until the cumulative value ΣQa of the intake air volume Qa since the start of the engine 22 reaches the predetermined value Qref. If it is determined in step S190 that the sum of the learned value AF2 and the correction value k minus the learned value AF1, and then further subtract the threshold value AFref1 ({(AF2+k)-AF1}-AFref1) is less than the threshold value Aref, i.e., if it is determined that dilution elimination was not achieved by a small amount, the process ends without resetting the fuel dilution amount Fd to zero. Also, if it is determined in step S200 that the cumulative value ΣQa of the intake air volume Qa has reached the predetermined value Qref, the process ends without resetting the fuel dilution amount Fd to zero.

[0031] If it is determined in step S160 that there is no history of air-fuel ratio learning in the high intake air volume region, the learned value AF2 of the air-fuel ratio learning in the low intake air volume region and the correction value k in the air-fuel ratio feedback control are input (step S210), and it is determined whether the sum of the learned value AF2 and the correction value k is equal to or greater than the threshold value AFref2 (step S220). Since the sum of the learned value AF2 and the correction value k is the actual air-fuel ratio, the determination in step S210 is whether the actual air-fuel ratio is equal to or greater than the threshold value AFref2. When the oil change is performed properly, the oil is no longer diluted by fuel, so the actual air-fuel ratio is close to the stoichiometric air-fuel ratio. On the other hand, when the oil change is not performed properly, the oil is not diluted by fuel, so the actual air-fuel ratio differs from the stoichiometric air-fuel ratio. Therefore, the threshold value AFref2 can be determined as a value within the allowable range of the actual air-fuel ratio relative to the stoichiometric air-fuel ratio when the oil change is performed properly. In the embodiment, value A12 is set to a value smaller than value A22, but value A12 and value A22 may be the same value. If it is determined in step S220 that the actual air-fuel ratio is equal to or greater than threshold value AFref2, it is determined that oil dilution with fuel has been eliminated, and the fuel dilution amount Fd is reset to 0, and the air-fuel ratio learning history is cleared (step S230), and this process ends. On the other hand, if it is determined in step S220 that the difference between the actual air-fuel ratio and the stoichiometric air-fuel ratio is less than threshold value AFref2, it is determined that oil dilution with fuel has not been eliminated, and this process ends without resetting fuel dilution amount Fd to 0.

[0032] In the engine system mounted on the hybrid vehicle 20 of the embodiment described above, in response to a request to reset the fuel dilution amount Fd, if there is a history of air-fuel ratio learning in the high intake air volume region, it is determined that oil dilution with fuel has been eliminated and the fuel dilution amount Fd is reset when the sum of the learned value AF2 of the air-fuel ratio learning in the low intake air volume region and the correction value k in the air-fuel ratio feedback control minus the learned value AF1 of the air-fuel ratio learning in the high intake air volume region ((AF2 + k) - AF2)) is equal to or greater than the threshold value AFref1. Furthermore, if there is no history of air-fuel ratio learning in the high intake air volume region, the actual air-fuel ratio is calculated based on the sum of the learned value AF2 of the air-fuel ratio learning in the low intake air volume region and the correction value k in the air-fuel ratio feedback control. If the actual air-fuel ratio is equal to or greater than the threshold value AFref2, it is determined that oil dilution with fuel has been eliminated and the fuel dilution amount Fd is reset. This allows the fuel dilution amount Fd to be reset after confirming that fuel dilution has been eliminated after an oil change. As a result, it is possible to prevent the fuel dilution amount Fd from being reset even when the oil change has not been performed properly, and it is possible to prevent the GPF 136 from overheating due to the regeneration process (temperature increase process) of the GPF 136 being performed when the fuel dilution amount Fd is large.

[0033] In the engine device mounted on the hybrid vehicle 20 of this embodiment, if there is a history of air-fuel ratio learning in the high intake air volume region and the dilution elimination determination is not made for a short time, the dilution elimination determination is made until the integrated value ΣQa of the intake air volume Qa since the start of the engine 22 reaches the predetermined value Qref. As a result, the dilution elimination determination can be made more appropriately. Note that even when there is no history of air-fuel ratio learning in the high intake air volume region, the dilution elimination determination may be continued until the integrated value ΣQa of the intake air volume Qa since the start of the engine 22 reaches the predetermined value Qref.

[0034] Although the engine device of the embodiment is mounted on the hybrid vehicle 20, it may be mounted on a moving body other than a vehicle or incorporated into stationary equipment.

[0035] The correspondence between the main elements of the embodiment and the main elements of the invention described in the "Means for Solving the Problem" section will be explained below. In the embodiment, the engine 22 corresponds to the "engine" and the engine ECU 24 corresponds to the "controller."

[0036] The correspondence between the main elements of the Examples and the main elements of the invention described in the "Means for Solving the Problem" section does not limit the elements of the invention described in the "Means for Solving the Problem" section, since the Examples are examples for specifically explaining the mode for implementing the invention described in the "Means for Solving the Problem" section. In other words, the interpretation of the invention described in the "Means for Solving the Problem" section should be based on the description in that section, and the Examples are merely specific examples of the invention described in the "Means for Solving the Problem" section.

[0037] The above describes the form for carrying out the present invention using examples, but the present invention is not limited to these examples in any way, and it goes without saying that the present invention can be carried out in various forms within the scope that does not deviate from the gist of the present invention. [Industrial Applicability]

[0038] The present invention can be used in the engine device manufacturing industry and the like. [Explanation of symbols]

[0039] 20 Hybrid vehicle, 22 Engine, 23 Crankshaft, 24 Engine ECU, 30 Motor, 32 Inverter, 34 Motor ECU, 40 Automatic transmission, 43 Torque converter, 44 Transmission input shaft, 45 Automatic transmission, 48 Differential gear, 49 Drive wheels, 60 High voltage battery, 62 Low voltage battery, 64 DC / DC converter, 70 HVECU.

Claims

1. An engine device including an engine having an in-cylinder injection valve and a control device that controls the engine, When a request for resetting an estimated value of oil dilution by fuel is made based on an oil change, the control device determines whether or not dilution by fuel has been eliminated based on a learned value in air-fuel ratio learning and / or a correction value in feedback control of the air-fuel ratio, and resets the estimated value of dilution when it is determined that dilution has been eliminated. An engine device characterized by:

2. 2. The engine device according to claim 1, When there is a history of air-fuel ratio learning for a high intake air amount region of the engine operating range in which the intake air amount is relatively large, the control device makes the dilution elimination determination based on the sum of a learned value of air-fuel ratio learning for a low intake air amount region in which the intake air amount is relatively small and a feedback control correction value, and the difference between the learned value of air-fuel ratio learning for the high intake air amount region related to the history. Engine equipment.

3. 3. The engine device according to claim 2, when there is no history of air-fuel ratio learning for the high intake air amount region, the control device makes the dilution cancellation determination based on a learned value of air-fuel ratio learning for a low intake air amount region in which the intake air amount is relatively small and the correction value. Engine equipment.

4. 2. The engine device according to claim 1, The reset request is made based on the fact that a dealer has operated an oil change switch or that a reset operation of the mileage after the oil change has been performed, A threshold value for determination is used for the dilution elimination determination when a reset request is made by the switch operation and for the dilution elimination determination when a reset request is made by the reset operation. Engine equipment.

5. An engine device according to any one of claims 1 to 4, When the control device determines that the dilution has not been eliminated to a small extent in the dilution elimination determination, the control device extends the period of the dilution elimination determination until the integrated intake air amount after starting the engine reaches a predetermined air amount. Engine equipment.

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