Engine device

Abstract

To appropriately suppress occurrence of knocking in an engine.SOLUTION: An engine device includes an engine equipped with a supercharger having a compressor attached into an intake pipe and outputting power by receiving supply of fuel from a fuel tank, and a control device for controlling ignition timing of the engine with the usage of a leaning value of KCS (knock control system) learning on the basis of occurrence or non-occurrence of knocking in the engine. The control device restricts a load factor of the engine so that the load factor becomes smaller as the learning value is closer to a value on the retard side, and so that the load factor becomes smaller as an engine speed is higher, and / or so that the load factor becomes smaller as an intake temperature of the engine is higher.SELECTED DRAWING: Figure 4

Description

[Technical field]

[0001] The present disclosure relates to an engine arrangement. [Background technology]

[0002] Conventionally, an engine device of this type has been proposed which sets a reference ignition timing for the engine in accordance with the engine's operating conditions, corrects the reference ignition timing to the retarded side in order to suppress knocking, sets a target air volume for outputting a target torque to the engine in accordance with the reference ignition timing or the ignition timing corrected to the retarded side, limits the target air volume so as not to exceed a threshold value set in accordance with the operating conditions, and controls the intake air volume in accordance with the target air volume limited to below the threshold value (see, for example, Patent Document 1). [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2017-155678 A Summary of the Invention [Problem to be solved by the invention]

[0004] In such engine systems, depending on the operating conditions and fuel properties, knocking can occur even if the ignition timing is retarded to near the misfire limit ignition timing, which is the ignition timing just before (slightly advanced from) the misfire region where misfires occur in the engine. This issue is of particular concern when the engine is equipped with a turbocharger and the engine load factor is high.

[0005] The main object of the engine device of the present disclosure is to more appropriately suppress the occurrence of knocking in the engine. [Means for solving the problem]

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

[0007] The engine device of the present disclosure comprises: An engine device comprising: an engine that includes a supercharger having a compressor attached in an intake pipe and receives fuel from a fuel tank to output power; and a control device that controls ignition timing of the engine using a learning value of a KCS (Knock control system) based on the occurrence or non-occurrence of knocking in the engine, the control device limits the load factor of the engine so that the learned value is smaller as the value is closer to the retarded angle side, and so that the load factor is smaller as the engine speed is higher and / or so that the load factor is smaller as the engine intake temperature is higher. The gist of the present invention is as follows.

[0008] In the engine device of the present disclosure, the load factor of the engine is limited so that the load factor becomes smaller as the learning value of the KCS learning becomes more retarded, and becomes smaller as the engine speed becomes higher and / or the intake air temperature of the engine becomes higher. By limiting the load factor in this manner, the occurrence of knocking in the engine can be more appropriately suppressed. The inventors have confirmed this through experiments, analysis, and the like. Note that the load factor may not be limited when the learning value is more advanced than a predetermined value, when the engine speed is less than a predetermined value, or when the intake air temperature is less than a predetermined temperature.

[0009] In the engine device of the present disclosure, a plurality of temperature sensors may be arranged in the intake pipe, and the control device may use the detection value of the sensor among the plurality of temperature sensors that is closest to the combustion chamber of the engine as the intake air temperature.

[0010] The engine device of the present disclosure may include a knocking sensor that detects knocking in the engine and an intake air temperature sensor that detects the intake air temperature, and the control device may set the learned value to a most retarded value when the knocking sensor is abnormal, and set the intake air temperature to a maximum temperature when the intake air temperature sensor is abnormal.

[0011] In the engine device of the present disclosure, the control device may set an upper limit load rate so that the learned value is smaller as the value is on the retard side, and so that the upper limit load rate is smaller as the rotation speed is higher and / or the intake air temperature is higher, and may control the engine by setting a target load rate by guarding an upper limit of a required load rate with the upper limit load rate. [Brief description of the drawings]

[0012] [Figure 1] 1 is a schematic configuration diagram of a hybrid vehicle 20 equipped with an engine device according to an embodiment of the present disclosure. [Diagram 2] 1 is a schematic diagram of an engine 22 mounted on a hybrid vehicle 20. FIG. [Diagram 3] 2 is an explanatory diagram showing an example of input / output signals of an engine ECU 24 mounted on a hybrid vehicle 20. FIG. [Figure 4] 5 is a flowchart showing an example of an upper limit load rate setting routine executed by an engine ECU 24. [Diagram 5] 4 is an explanatory diagram showing an example of the relationship between the load factor KL and the ignition timing Ti of the engine 22. FIG. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0013] An embodiment of the present disclosure will be described with reference to the drawings. Fig. 1 is a schematic diagram of a hybrid vehicle 20 equipped with an engine device according to an embodiment of the present disclosure. Fig. 2 is a schematic diagram of an engine 22 equipped in the hybrid vehicle 20. Fig. 3 is an explanatory diagram showing an example of input / output signals of an engine electronic control unit (hereinafter referred to as "engine ECU") 24 equipped in the hybrid vehicle 20.

[0014] As shown in FIG. 1, the hybrid vehicle 20 of the embodiment includes an engine 22, an engine ECU 24, a motor 30, an inverter 32, a motor electronic control unit (hereinafter referred to as the "motor ECU") 34, a clutch K0, a power transmission device 40, and a hybrid electronic control unit (hereinafter referred to as the "HVECU") 70.

[0015] The engine 22 is configured as a multiple cylinder internal combustion engine that uses a hydrocarbon fuel such as gasoline from a fuel tank and outputs power through four strokes: intake, compression, expansion (explosive combustion), and exhaust. As shown in Fig. 2, the engine 22 has a port injection valve 130 that injects fuel into an intake port and an in-cylinder injection valve 131 that injects fuel into a combustion chamber 133, and can be operated in any one of a port injection mode, an in-cylinder injection mode, and a common injection mode. In the port injection mode, air purified by an air cleaner 122 is sucked into an intake pipe 123, passes through an intercooler 125 and a throttle valve 126 arranged in the intake pipe 123, and further passes through a surge tank 127, an intake manifold 128, and an intake port 129, and fuel is injected from the port injection valve 130 into the intake port 129, and the air and fuel are mixed. This mixture is drawn into the combustion chamber 133 via the intake valve 132, where it is explosively combusted by an electric spark from the spark plug 134. The reciprocating motion of the piston 135, which is pushed down by the energy of the explosive combustion, is converted into the rotational motion of the crankshaft 23. In the in-cylinder injection mode, air is drawn into the combustion chamber 133 as in the port injection mode, and fuel is injected from the in-cylinder injection valve 131 once or multiple times during the intake stroke or compression stroke, and is explosively combusted by an electric spark from the spark plug 134, to obtain the rotational motion of the crankshaft 23. In the shared injection mode, fuel is injected from the port injection valve 130 when air is drawn into the combustion chamber 133, and fuel is injected from the in-cylinder injection valve 131 once or multiple times during the intake stroke or compression stroke, and is explosively combusted by an electric spark from the spark plug 134, to obtain the rotational motion of the crankshaft 23. Exhaust gas discharged from the combustion chamber 133 to an exhaust pipe 143 via an exhaust valve 140, an exhaust port 141, and an exhaust manifold 142 is discharged to the outside air via a purification device 145. The purification device 145 has a catalyst (three-way catalyst) 145a that purifies harmful components such as carbon monoxide (CO), hydrocarbons (HC), and nitrogen oxides (NOx).

[0016] The engine 22 includes a supercharger 160. The supercharger 160 is configured as a turbocharger, and includes a compressor 161, a turbine 162, a connecting shaft 163, a wastegate valve 164, and a blow-off valve 165. The compressor 161 is disposed upstream of the intercooler 125 of the intake pipe 123. The turbine 162 is disposed upstream of the purification device 145 of the exhaust pipe 143. The connecting shaft 163 connects the compressor 161 and the turbine 162. The wastegate valve 164 is provided in a bypass pipe 144 that connects the upstream side and downstream side of the turbine 162 in the exhaust pipe 143, and is controlled by the engine ECU 24. The blow-off valve 165 is provided in a bypass pipe 124 that connects the upstream side and downstream side of the compressor 161 in the intake pipe 123, and is controlled by the engine ECU 24.

[0017] In this turbocharger 160, the engine ECU 24 adjusts the opening of the wastegate valve 164 to adjust the distribution ratio between the amount of exhaust gas flowing through the bypass pipe 144 and the amount of exhaust gas flowing through the turbine 162, thereby adjusting the rotational driving force of the turbine 162, adjusting the amount of air compressed by the compressor 161, and adjusting the supercharging pressure (intake pressure) of the engine 22. In detail, the distribution ratio is adjusted so that the smaller the opening of the wastegate valve 164, the smaller the amount of exhaust gas flowing through the bypass pipe 144 and the larger the amount of exhaust gas flowing through the turbine 162. When the wastegate valve 164 is fully open, the engine 22 can operate in the same manner as a naturally aspirated engine without the turbocharger 160.

[0018] Furthermore, in the turbocharger 160, when the pressure downstream of the compressor 161 in the intake pipe 123 is somewhat higher than the pressure upstream of the intake pipe 123, the blow-off valve 165 is opened to release the excess pressure downstream of the compressor 161. Note that, instead of a valve controlled by the engine ECU 24, the blow-off valve 165 may be configured as a check valve that opens when the pressure downstream of the compressor 161 in the intake pipe 123 becomes somewhat higher than the pressure upstream of the intake pipe 123.

[0019] The engine ECU 24 includes a microcomputer having a CPU, a ROM, a RAM, a flash memory, an input / output port, and a communication port, various drive circuits, various logic ICs, etc. As shown in Fig. 3, the engine ECU 24 receives, for example, a crank angle θcr from a crank position sensor 150 that detects the rotational position of the crankshaft 23 of the engine 22, a coolant temperature Tw from a water temperature sensor 151 that detects the temperature of the coolant of the engine 22, and an oil temperature To from an oil temperature sensor 152 that detects the temperature of the engine oil. The engine ECU 24 also receives a throttle opening TH from a throttle position sensor 126a that detects the opening of the throttle valve 126. The engine ECU 24 also receives cam angles θci, θco from a cam position sensor 153 that detects the rotational position of an intake camshaft that opens and closes the intake valve 132 and the rotational position of an exhaust camshaft that opens and closes the exhaust valve 140. The engine ECU 24 also receives an intake air amount Qa from an air flow meter 123a attached upstream of the compressor 161 in the intake pipe 123 and a first intake air temperature Ta1 from a first intake air temperature sensor 123t attached upstream of the compressor 161 in the intake pipe 123. The engine ECU 24 also receives an intake pressure (pre-compressor pressure) Pa1 from a first pressure sensor 123b attached upstream of the compressor 161 in the intake pipe 123 and a supercharging pressure (post-compressor pressure) Pa2 from a second pressure sensor 123c attached between the compressor 161 and the intercooler 125 in the intake pipe 123. The engine ECU 24 also receives inputs of a surge pressure (post-throttle pressure) Pa3 from a third pressure sensor 127a attached to the surge tank 127, a second intake air temperature Ta2 from a second intake air temperature sensor 127t attached to the surge tank 127, and a third intake air temperature Ta3 from a third intake air temperature sensor 128t attached to the intake manifold 128. The engine ECU 24 also receives inputs of a front air-fuel ratio AF1 from a front air-fuel ratio sensor 146a attached in the exhaust pipe 143 between the turbine 162 of the turbocharger 160 and the purification device 145, and a rear air-fuel ratio AF2 from a rear air-fuel ratio sensor 146b attached in the exhaust pipe 143 downstream of the purification device 145.The engine ECU 24 also receives a knock signal Ks from a knock sensor 154 that is attached to the cylinder block and detects vibrations that occur with the occurrence of knocking.

[0020] The engine ECU 24 outputs, for example, a control signal to the throttle valve 126, a control signal to the port injection valve 130, a control signal to the in-cylinder injection valve 131, and a control signal to the spark plug 134. The engine ECU 24 also outputs a control signal to a wastegate valve 164 and a control signal to a blow-off valve 165. 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 150. The engine ECU 24 calculates a load factor KL (the ratio of the volume of air actually taken in one 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.

[0021] 1, a starter motor 25 for cranking the engine 22 and an alternator 26 for generating power 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.

[0022] The motor 30 is configured as a synchronous generator motor, and has a rotor in which a permanent magnet is embedded in a rotor core, and a stator in which a three-phase coil is wound around a stator core. 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 is also connected to an input shaft 41 of a power transmission device 40. An inverter 32 is used to drive the motor 30. The inverter 32 is also connected to a high-voltage side power line 61 together with a high-voltage battery 60. The motor 30 is rotationally driven by a motor ECU 34 controlling the switching of multiple switching elements of the inverter 32.

[0023] The motor ECU 34 includes a microcomputer and the like, similar to the engine ECU 24. The motor ECU 34 receives, for example, a rotational position θmg from a rotational position sensor 30a that detects the rotational position of a rotor (rotating shaft 31) of the motor 30, and phase currents Iu, Iv from current sensors that detect phase currents of each phase of the motor 30. The motor ECU 34 outputs, for example, a control signal to the inverter 32. The motor ECU 34 calculates the rotation 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.

[0024] 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 rotating shaft 31 of the motor 30.

[0025] The power transmission device 40 includes a torque converter 43 and an automatic transmission 45. The torque converter 43 is configured as a general fluid transmission device, and transmits the power of the input shaft 41 connected to the rotating shaft 31 of the motor 30 to an intermediate shaft 44 that is an input shaft of the automatic transmission 45 with the torque amplified, or transmits the torque as is without amplifying it. The automatic transmission 45 has the intermediate shaft 44, an output shaft 42 connected to driving wheels 49 via a differential gear 48, at least one planetary gear mechanism, and a plurality of hydraulically driven friction engagement elements (clutches, brakes). The automatic transmission 45 forms a plurality of forward and reverse gears by selectively engaging some of the plurality of friction engagement elements, and transmits power between the intermediate shaft 44 and the output shaft 42. The hydraulic pressure of the hydraulic oil from a mechanical oil pump or an electric oil pump is adjusted and supplied to the clutch K0 and the automatic transmission 45 by a hydraulic control device (not shown). The automatic transmission 45 may be, for example, a continuously variable transmission (CVT) or a dual clutch transmission.

[0026] High-voltage battery 60 is configured as, for example, a lithium-ion secondary battery or a nickel-hydrogen 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 lithium-ion secondary battery or 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. This DC / DC converter 64 steps down the power of high-voltage power line 61 and supplies it to low-voltage power line 63.

[0027] The HVECU 70 includes a microcomputer and the like, similar to the engine ECU 24. The HVECU 70 receives, for example, a rotation speed Nin from a rotation speed sensor 41a attached to the input shaft 41 of the power transmission device 40, a rotation speed Nmi from a rotation speed sensor 44a attached to the intermediate shaft 44 of the power transmission device 40, and a rotation speed Nout from a rotation speed sensor 42a attached to the output shaft 42 of the power transmission device 40. The HVECU 70 also receives a voltage Vb1 from a voltage sensor attached between the terminals of the high-voltage battery 60, a current Ib1 from a current sensor attached to the output terminal of the high-voltage battery 60, a voltage Vb2 from a voltage sensor attached between the terminals of the low-voltage battery 62, and a current Ib2 from a current sensor attached to the output terminal of the low-voltage battery 62. 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.

[0028] The HVECU 70 outputs, for example, a control signal to the starter motor 25, a control signal to the alternator 26, a control signal to the clutch K0 and the power transmission device 40 (hydraulic control device), and a control signal to the DC / DC converter 64. 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 power transmission device 40 by dividing the rotation speed Nin of the input shaft 41 of the power transmission device 40 from the rotation speed sensor 41a by the rotation speed Nout of the output shaft 42 of the power transmission device 40 from the rotation speed sensor 42a.

[0029] In the hybrid vehicle 20 of the embodiment thus configured, the HVECU 70, the engine ECU 24, and the motor ECU 34 control the engine 22, the clutch K0, the motor 30, and the power transmission device 40 through cooperative control so as to run in a hybrid driving mode (HV driving mode) or an electric driving mode (EV driving mode). Here, the HV driving mode is a mode in which the clutch K0 is in an engaged state and the vehicle runs using the power of the engine 22, and the EV driving mode is a mode in which the clutch K0 is in a released state and the vehicle runs without using the power of the engine 22.

[0030] In the control of the power transmission device 40 in the HV driving mode and the EV driving mode, the HVECU 70 sets a target gear Gs* of the automatic transmission 45 based on the accelerator opening Acc and the vehicle speed V, and controls the automatic transmission 45 so that the gear Gs of the automatic transmission 45 becomes the target gear Gs*. In the control of the engine 22 and the motor 30 in the HV driving mode, the HVECU 70 sets a required torque Tin* of the input shaft 41 of the power transmission device 40 based on the accelerator opening Acc, the vehicle speed V, and the rotation speed ratio Gt of the power transmission device 40, sets a target torque Te* of the engine 22 and a torque command Tm* of the motor 30 so that the required torque Tin* is output to the input shaft 41, and transmits the target torque Te* to the engine ECU 24 and transmits the torque command Tm* to the motor ECU 34. The engine ECU 24 controls the operation of the engine 22 so that the engine 22 is operated at the target torque Te*. The motor ECU 34 performs switching control of a plurality of switching elements of the inverter 32 so that the motor 30 is driven by the torque command Tm*. Since the control of the engine 22 and the motor 30 in the EV driving mode is not central to the present invention, detailed description thereof will be omitted.

[0031] The operation control of the engine 22 will be described in detail. The engine ECU 24 sets a required load rate KLrq based on the target torque Te* of the engine 22, sets a target load rate KL* by guarding the upper limit of the set required load rate KLrq with an upper limit load rate KLmax, and performs intake air amount control, fuel injection control, ignition control, and supercharging control based on the target load rate KL*. A method for setting the upper limit load rate KLmax will be described later. In the intake air amount control, the opening degree of the throttle valve 126 is controlled. In the fuel injection control, fuel injection from the port injection valve 130 and fuel injection from the in-cylinder injection valve 131 are controlled. In the ignition control, the ignition timing of the spark plug 134 is controlled. In the supercharging control, the opening degree of the wastegate valve 164 is controlled.

[0032] The details of the ignition control will be described. In the ignition control, first, the basic ignition timing Tibs and the misfire limit ignition timing Tifc are set based on the rotation speed Ne and the load factor KL. Here, the basic ignition timing Tibs can be set to, for example, an ignition timing (MBT: Minimum spark advance for Best Torque) that maximizes the output torque of the engine 22. The misfire limit ignition timing Tifc is determined by experiment, analysis, or the like as an ignition timing immediately before (slightly advanced from) the misfire region where misfire occurs in the engine 22. After the basic ignition timing Tibs and the misfire limit ignition timing Tifc are set in this way, a value obtained by adding a learning value (correction value) α to the basic ignition timing Tibs is set as a target ignition timing Ti* within a range in which the misfire limit ignition timing Tifc is the most retarded angle, and the ignition plug 134 is controlled so that ignition is performed at the target ignition timing Ti*. The learning value α is set for each region divided according to the rotation speed Ne and the load factor KL by KCS (Knock control system) learning. In KCS learning, for each region, when it is determined that knocking is not occurring based on the knock signal Ks from the knock sensor 154, the learning value α is updated to the advance side (the side that advances the ignition timing), and when it is determined that knocking is occurring, the learning value α is updated to the retard side (the side that delays the ignition timing).

[0033] Next, the operation of the engine device provided in the hybrid vehicle 20 of the embodiment, in particular, the process of setting the upper limit load rate KLmax will be described. Fig. 4 is a flowchart showing an example of an upper limit load rate setting routine executed by the engine ECU 24. This routine is repeatedly executed while the engine 22 is in operation.

[0034] 2 is executed, the engine ECU 24 first inputs the learning value α, the rotation speed Ne, and the intake air temperature Ta (step S100). Here, the learning value α is input with a value set (updated) by the above-mentioned KCS learning. The rotation speed Ne is input with a value calculated based on the crank angle θcr. The intake air temperature Ta is input with a value detected by the intake air temperature sensor closest to the combustion chamber 133 among the first intake air temperature sensor 123t, the second intake air temperature sensor 127t, and the third intake air temperature sensor 128t, specifically, the third intake air temperature Ta3 detected by the third intake air temperature sensor 128t.

[0035] When the data is input in this way, the upper limit load rate KLmax is set based on the input learning value α, the rotation speed Ne, and the intake air temperature Ta (step S110), and this routine ends. Here, the upper limit load rate KLmax can be set by, for example, applying the learning value α, the rotation speed Ne, and the intake air temperature Ta to an upper limit load rate map that is determined in advance by experiment, analysis, or machine learning as the relationship between the learning value α, the rotation speed Ne, the intake air temperature Ta, and the upper limit load rate KLmax to derive the upper limit load rate KLmax. The upper limit load rate map is set so that the upper limit load rate KLmax becomes smaller as the learning value α is on the retard side, the upper limit load rate KLmax becomes smaller as the rotation speed Ne is larger, and the upper limit load rate KLmax becomes smaller as the intake air temperature Ta is higher. Note that when the learning value α is a value on the advance side of the threshold value αref, when the rotation speed Ne is less than the threshold value Neref, or when the intake air temperature Ta is less than the threshold value Taref, the load rate may not be limited. The reason for setting the upper limit load rate KLmax in this way will be described below.

[0036] FIG. 5 is an explanatory diagram showing an example of an analysis result of the relationship between the load factor KL of the engine 22 and the ignition timing when a certain rotation speed Ne and a certain intake air temperature Ta are used. In the figure, the solid line indicates the knocking ignition timing Tik for each octane number of the fuel, and the dashed line indicates the misfire limit ignition timing Tifc. The knocking ignition timing Tik is the ignition timing immediately before (slightly on the retard side) the knocking region where knocking occurs in the engine 22. As shown in the figure, the knocking ignition timing Tik is more retarded as the load factor KL increases and the octane number of the fuel decreases. Also, the misfire limit ignition timing Tifc is more advanced as the load factor KL increases. Therefore, the range from the misfire limit ignition timing Tifc to the knocking ignition timing Tik (the ignition timing range in which the occurrence of knocking and misfire can be sufficiently suppressed) becomes narrower as the load factor KL increases and as the octane number of the fuel decreases. The inventors have confirmed that the lower the octane number of the fuel and the higher the load rate KL, the more likely knocking occurs even if the ignition timing is retarded to the vicinity of the misfire limit ignition timing Tifc. In addition, the inventors have confirmed through experiments and analysis that the lower the octane number of the fuel, the more likely the learning value α of the KCS learning is to be on the retard side. Based on this, in the embodiment, the upper limit load rate KLmax is set so that it becomes smaller as the learning value α of the KCS learning becomes on the retard side. In addition, the inventors have confirmed through experiments and analysis that the higher the load rate KL, the higher the rotation speed Ne, and the higher the intake air temperature Ta, the more likely knocking occurs even if the ignition timing is retarded to the vicinity of the misfire limit ignition timing Tifc. Based on this, in the embodiment, the upper limit load rate KLmax is set so that it becomes smaller as the rotation speed Ne becomes larger and as the intake air temperature Ta becomes higher. In this way, by setting the upper limit load rate KLmax so that it becomes smaller as the octane number of the fuel is lower (as the learning value α of the KCS learning is more retarded), as the rotation speed Ne is higher, and as the intake air temperature Ta is higher, the occurrence of knocking in the engine 22 can be more appropriately suppressed.

[0037] In the engine device mounted on the hybrid vehicle 20 of the present embodiment described above, the engine ECU 24 sets the upper limit load rate KLmax based on the learning value α of the KCS learning, the rotation speed Ne, and the intake air temperature Ta. Specifically, the upper limit load rate KLmax is set so that the upper limit load rate KLmax becomes smaller as the learning value α is on the retard side, the upper limit load rate KLmax becomes smaller as the rotation speed Ne becomes larger, and the upper limit load rate KLmax becomes smaller as the intake air temperature Ta becomes higher. Then, the target load rate KL* is set by upper limit guarding the required load rate KLrq with the upper limit load rate KLmax, and the intake air amount control, fuel injection control, ignition control, and supercharging control are performed based on the target load rate KL*. This makes it possible to more appropriately suppress the occurrence of knocking in the engine 22.

[0038] In the above-described embodiment, the engine ECU 24 sets the upper limit load rate KLmax based on the learning value α of the KCS learning, the rotation speed Ne, and the intake air temperature Ta. However, instead of this, the upper limit load rate KLmax may be set based on the learning value α and the rotation speed Ne without using the intake air temperature Ta. Also, the upper limit load rate KLmax may be set based on the learning value α and the intake air temperature Ta without using the rotation speed Ne.

[0039] In the above embodiment, the engine ECU 24 sets the upper limit load rate KLmax so that the upper limit load rate KLmax decreases as the learning value α of the KCS learning becomes more retarded. However, when the knock sensor 154 is abnormal, the most retarded value in the expected range may be used as the learning value α. In this way, the occurrence of knocking in the engine 22 can be further suppressed when the knock sensor 154 is abnormal.

[0040] In the above embodiment, the engine ECU 24 sets the upper limit load rate KLmax so that the higher the intake air temperature Ta, the smaller the upper limit load rate KLmax becomes. However, when the third intake air temperature sensor 128t is abnormal, the highest temperature in the assumed range may be used as the intake air temperature Ta. In this way, the occurrence of knocking in the engine 22 can be further suppressed when the third intake air temperature sensor 128t is abnormal.

[0041] In the above-described embodiment, the second intake air temperature sensor 127t attached to the surge tank 127 and the third intake air temperature sensor 128t attached to the intake manifold 128 are provided. However, only one of these may be provided.

[0042] In the embodiment described above, the engine 22 is provided with the port injection valve 130 and the in-cylinder injection valve 131. However, the engine 22 may be provided with only one of these.

[0043] In the above-described embodiment, the supercharger 160 is configured as a turbocharger in which the compressor 161 arranged in the intake pipe 123 and the turbine 162 arranged in the exhaust pipe 143 are connected via the connecting shaft 163. However, instead of this, the supercharger may be configured as a supercharger in which a compressor driven by the engine 22 or a motor is arranged in the intake pipe 123.

[0044] In the above-described embodiment, the engine ECU 24, the motor ECU 34, and the HVECU 70 are provided. However, at least two of these may be integrally configured.

[0045] In the above-described embodiment, the engine device is mounted on the hybrid vehicle 20 having the engine 22 and the motor 30, but is not limited thereto. For example, the engine device may be mounted on a vehicle having an engine but not a motor. The engine device may be mounted on a moving body other than a vehicle, or on a non-moving construction facility or the like.

[0046] The relationship between the main elements of the embodiment and the main elements of the invention described in the section on means for solving the problems will be described. In the embodiment, the engine 22 corresponds to the "engine" and the engine ECU 24 corresponds to the "control device."

[0047] Note that the correspondence between the main elements of the embodiment and the main elements of the invention described in the Means for Solving the Problem column does not limit the elements of the invention described in the Means for Solving the Problem column, since the embodiment is an example for specifically explaining the form for implementing the invention described in the Means for Solving the Problem column. In other words, the interpretation of the invention described in the Means for Solving the Problem column should be made based on the description in that column, and the embodiment is merely a specific example of the invention described in the Means for Solving the Problem column.

[0048] The above describes embodiments for implementing the present disclosure, but the present disclosure is not limited to these embodiments, and it goes without saying that the present disclosure can be implemented in various forms without departing from the gist of the present disclosure. [Industrial Applicability]

[0049] The present disclosure is applicable to the engine device manufacturing industry and the like. [Explanation of symbols]

[0050] 20 hybrid vehicle, 22 engine, 23 crankshaft, 24 engine ECU, 25 starter motor, 26 alternator, 30 motor, 30a rotational position sensor, 31 rotating shaft, 32 inverter, 34 motor ECU, 40 power transmission device, 41 input shaft, 41a rotational speed sensor, 42 output shaft, 42a rotational speed sensor, 43 torque converter, 44 intermediate shaft, 44a rotational speed sensor, 45 automatic transmission, 48 differential gear, 49 drive wheel, 60 high voltage battery, 61 high voltage side power line, 62 low voltage battery, 63 low voltage side power line, 64 DC / DC converter, 70 HVECU, 80 ignition switch, 81 shift lever, 82 shift position sensor, 83 accelerator pedal, 84 accelerator pedal position sensor, 85 brake pedal, 86 brake pedal position sensor, 87 vehicle speed sensor, 122 air cleaner, 123 intake pipe, 123a air flow meter, 123b first pressure sensor, 123c second pressure sensor, 123t first intake air temperature sensor, 124 bypass pipe, 125 intercooler, 126 throttle valve, 126a throttle position sensor, 127 surge tank, 127a third pressure sensor, 127t second intake air temperature sensor, 128 intake manifold, 128t third intake air temperature sensor, 129 intake port, 130 port injection valve, 131 in-cylinder injection valve, 132 intake valve, 133 combustion chamber, 134 spark plug, 135 piston, 140 exhaust valve, 141 exhaust port, 142 exhaust manifold, 143 exhaust pipe, 144 bypass pipe, 145 purification device, 146a Front air-fuel ratio sensor, 146b rear air-fuel ratio sensor, 150 crank position sensor, 151 water temperature sensor, 152 oil temperature sensor, 153 cam position sensor, 154 knock sensor, 160 turbocharger, 161 compressor, 162 turbine, 163 connecting shaft, 164 wastegate valve, 165 blow-off valve.

Claims

1. An engine device comprising: an engine that includes a supercharger having a compressor attached in an intake pipe and receives fuel from a fuel tank to output power; and a control device that controls ignition timing of the engine using a learning value of a KCS (Knock control system) based on the occurrence or non-occurrence of knocking in the engine, the control device limits the load factor of the engine so that the learned value is smaller as the value is closer to the retarded angle side, and so that the load factor is smaller as the engine speed is higher and / or so that the load factor is smaller as the engine intake temperature is higher. Engine equipment.

2. 2. The engine device according to claim 1, A plurality of temperature sensors are disposed in the intake pipe, the control device uses a detection value of a sensor among the plurality of temperature sensors that is closest to a combustion chamber of the engine as the intake air temperature. Engine equipment.

3. 3. The engine device according to claim 1 or 2, A knocking sensor for detecting knocking in the engine; an intake air temperature sensor for detecting the intake air temperature; Equipped with the control device uses a most retarded value in a first assumed range as the learned value when the knocking sensor is abnormal, and uses a most high temperature in a second assumed range as the intake air temperature when the intake air temperature sensor is abnormal. Engine equipment.

4. 3. The engine device according to claim 1 or 2, the control device sets an upper limit load rate so that the learned value is smaller as the value is on the retard side, and is smaller as the rotation speed is larger and / or the intake air temperature is higher, and sets a target load rate by guarding an upper limit of a required load rate with the upper limit load rate, thereby controlling the engine. Engine equipment.

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