Engine equipment

Abstract

To realize excellent startability of an engine even when the engine stops at a position where electromagnetic pickup has a missing tooth.SOLUTION: An engine device comprises an engine having an in-cylinder injection valve, a motor connected to an output shaft of the engine via a clutch, a control device that controls the engine, the motor and the clutch, and a crank angle sensor having a timing rotor with a missing tooth and an electromagnetic pickup. When the electromagnetic pickup is at the position of the missing tooth when the engine is stopped, the control device performs at least one of fuel injection amount correction for correcting a fuel injection amount to stabilize combustion due to ignition and ignition timing correction for correcting an ignition timing to suppress the shock of initial explosion.SELECTED DRAWING: Figure 3

Description

[Technical field]

[0001] The present invention relates to an engine device, and more particularly to an engine device including an engine and a motor connected to an output shaft of the engine via a clutch. [Background technology]

[0002] Conventionally, as an engine device of this type, one that takes into consideration the position of the missing tooth, which is the reference position of the timing rotor, when stopping the operation of the engine has been proposed (see, for example, Patent Document 1). In this device, the reference position of the timing rotor is controlled so that it stops as the crankshaft stops rotating within a target stopping range from a stopping position determined by subtracting from 360-degree crank angle the sum of the angle at which the crankshaft is expected to rotate within a preparation time consisting of a mask time required to detect the missing tooth of the timing rotor when starting the engine and an angle required to detect the reference position of the timing rotor, from that position, which is a predetermined angle before that position. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2009-275635 A Summary of the Invention [Problem to be solved by the invention]

[0004] However, in the above engine device, when the engine stops with the electromagnetic pickup at the missing tooth position, the crank angle cannot be detected accurately, and the starting performance of the engine is reduced. In particular, when starting the engine by injecting fuel and igniting in the cylinder that first reaches the compression top dead center, the fuel injection amount and ignition timing are set for the air amount that differs depending on the stop crank angle, so when the engine stops with the electromagnetic pickup at the missing tooth position, the combustion at the first explosion is unstable and the shock of the first explosion becomes large.

[0005] The main object of the engine device of the present invention is to provide a good starting performance of the engine even when the engine stops with the electromagnetic pickup at the position of the missing tooth. [Means for solving the problem]

[0006] In order to achieve the above-mentioned main object, the engine device of the present invention employs the following means.

[0007] The engine device of the present invention comprises: An engine device including an engine having an in-cylinder injection valve, a motor connected to a crankshaft of the engine via a clutch, and a control device that controls the engine, the motor, and the clutch, a crank angle sensor including a timing rotor attached to the crankshaft and having a plurality of protrusions formed on its outer periphery at equal angular intervals except for some missing teeth, and an electromagnetic pickup that detects the passage of the protrusions in response to rotation of the timing rotor, the control device, when controlling the engine, the motor, and the clutch so as to half-engage the clutch to crank the engine by the motor and to start the engine by injecting fuel and igniting into a cylinder which first reaches a compression top dead center in the engine, sets an ignition timing for the cylinder which first reaches a compression top dead center based on a stop crank angle when the engine is stopped, a target crank torque when cranking by the motor, and a rotation speed of the motor; When the electromagnetic pickup is located at the missing tooth position when the engine is stopped, the control device performs at least one of a fuel injection amount correction for correcting a fuel injection amount so that combustion by ignition becomes stable, or an ignition timing correction for correcting an ignition timing so that a shock of an initial explosion is suppressed. It is characterized by:

[0008] The engine device of the present invention includes an engine having an in-cylinder injection valve, a motor connected to an output shaft of the engine via a clutch, a control device for controlling the engine, the motor, and the clutch, a timing rotor attached to a crankshaft with a plurality of protrusions formed on its outer periphery at equal angular intervals except for some missing teeth, and a crank angle sensor having an electromagnetic pickup for detecting passage of the protrusions in accordance with the rotation of the timing rotor. When controlling the engine, the motor, and the clutch to crank the engine with the clutch partially engaged and to start the engine by injecting fuel and igniting into the cylinder that first reaches compression top dead center in the engine, the control device sets the fuel injection amount for the cylinder that first reaches compression top dead center based on the elapsed time since the engine was stopped and sets the ignition timing based on the stop crank angle when the engine was stopped.

[0009] The stop crank angle of the cylinder that first reaches the compression top dead center is within 180 degrees before the compression top dead center (TDC) in a four-cylinder engine, and within 120 degrees before the compression top dead center in a six-cylinder engine. Therefore, in order to perform fuel injection and ignition (initial explosion) in the cylinder that first reaches the compression top dead center, fuel is injected during the compression stroke from the stop crank angle to the compression top dead center, and ignition is performed near the compression top dead center. The reason for setting the fuel injection amount based on the elapsed time since the engine was stopped when starting the engine is that the amount of air in the cylinder that first reaches the compression top dead center decreases as the elapsed time since the engine was stopped increases. The fuel injection amount for the cylinder that first reaches the compression top dead center when starting the engine may be set based not only on the elapsed time since the engine was stopped, but also on the stop crank angle (piston position) and the pressure in the intake manifold (intake manifold pressure) at the timing when the intake valve is closed. The reason why the fuel injection amount is set based on the stop crank angle (piston position) is that the closer the piston position is to the compression top dead center, the higher the pressure inside the cylinder, making it easier for air to escape from the piston rings. The reason why the fuel injection amount is set based on the intake manifold pressure is that the higher the intake manifold pressure, the greater the amount of air inside the cylinder. Thus, in order to obtain good startability at the first explosion, the fuel injection amount for the cylinder that first reaches the compression top dead center can be set to be smaller the longer the elapsed time since the engine was stopped, to be smaller the closer the stop crank angle (piston position) is to the compression top dead center, and to be larger the higher the intake manifold pressure.

[0010] In addition, the further the stop crank angle is from the compression top dead center (the larger the BTDC), the larger the amount of air in the cylinder, and the larger the shock at the time of the initial explosion, so it is preferable to retard the ignition timing to reduce the shock. The ignition timing for the cylinder that first reaches the compression top dead center when starting the engine may be set based on not only the stop crank angle but also the target cranking torque when cranking by the motor and the rotation speed of the motor. The reason for setting the ignition timing based on the target cranking torque is that the target cranking torque is set to be larger as the amount of air in the cylinder that first reaches the compression top dead center is larger, and the larger the amount of air in the cylinder, the larger the shock, so it is preferable to retard the ignition timing to reduce the shock. The reason for setting the ignition timing based on the rotation speed of the motor is that the larger the rotation speed of the motor is, the longer it takes to make the rotation speed of the engine immediately after starting the engine approximately equal to the rotation speed of the motor, so it is preferable to increase the torque of the engine even at the initial explosion to increase the rotation speed. As described above, in order to suppress the shock caused by the initial explosion, the ignition timing of the cylinder that reaches the compression top dead center first can be set to be more retarded the further the stopping crank angle is from the compression top dead center of the target cylinder, more retarded the larger the target crank torque is, and more advanced the higher the motor speed is.

[0011] In the engine system of the present invention, when the electromagnetic pickup of the crank angle sensor is located at the missing tooth of the timing rotor when the engine is stopped, the control device performs at least one of fuel injection amount correction to correct the fuel injection amount so that the combustion caused by ignition is stabilized, or ignition timing correction to correct the ignition timing to suppress the shock of the initial explosion. The fuel injection amount correction corresponds to a correction to the fuel injection amount when the amount of air in the cylinder is the largest in the crank angle range of the missing tooth. The ignition timing correction corresponds to a correction to the ignition timing when the amount of air in the cylinder is the largest in the crank angle range of the missing tooth. This allows the engine to have good startability even when the engine is stopped with the electromagnetic pickup located at the missing tooth.

[0012] In the engine system of the present invention, when the electromagnetic pickup is at the position of the missing tooth when the engine is stopped, the control device may use the crank angle farthest from the compression top dead center of the cylinder that first reaches the compression top dead center within the crank angle range caused by the missing tooth as the stop crank angle. By setting the stop crank angle to the crank angle farthest from the compression top dead center within the crank angle range caused by the missing tooth, it is possible to assume a case in which the amount of air in the cylinder that first reaches the compression top dead center within the crank angle range caused by the missing tooth is the largest, and to start the engine using a fuel injection amount and ignition timing suitable for this assumption. [Brief description of the drawings]

[0013] [Figure 1] FIG. 1 is a diagram showing an outline of the configuration of a hybrid vehicle 20 according to an embodiment of the present invention. [Diagram 2] FIG. 2 is a diagram showing an outline of the configuration of an engine 22. [Diagram 3] 4 is a flowchart showing an example of a startup initial explosion process executed by an engine ECU 24 or an HVECU 70. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0014] Next, a mode for carrying out the present invention will be described using examples. EXAMPLES

[0015] Fig. 1 is a schematic diagram showing the configuration of a hybrid vehicle 20 equipped with an engine device according to an embodiment of the present invention. Fig. 2 is a schematic diagram showing the configuration of an engine 22 equipped in the hybrid vehicle 20. As shown in Fig. 1, the hybrid vehicle 20 of the embodiment includes the engine 22, a motor 30, an inverter 32, a clutch K0, an automatic transmission 40, a high-voltage battery 60, a low-voltage battery 62, a DC / DC converter 64, and a hybrid electronic control unit (hereinafter referred to as "HVECU") 70.

[0016] The engine 22 is configured as a six-cylinder internal combustion engine that uses fuel such as gasoline or diesel to output power through four strokes: intake, compression, expansion (explosive combustion), and exhaust. 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 can be operated in any one of a port injection mode, an in-cylinder injection mode, and a common injection mode by having the port injection valve 126 and the in-cylinder injection valve 127. In the port injection mode, air purified by the air cleaner 122 is sucked into the intake pipe 123 and passes through the throttle valve 124 and the surge tank 125, and fuel is injected from the port injection valve 126 downstream of the surge tank 125 of the intake pipe 123, and the air and fuel are mixed. This mixture is then drawn into the combustion chamber 129 via the intake valve 128, where it is explosively combusted by an electric spark from the spark plug 130, and the reciprocating motion of the piston 132, which is pushed down in the cylinder bore by the energy of the mixture, is converted into the rotational motion of the crankshaft 23. In the in-cylinder injection mode, air is drawn into the combustion chamber 129 in the same manner as in the port injection mode, and fuel is injected from the in-cylinder injection valve 127 during the intake stroke and compression stroke, and is explosively combusted by an electric spark from the spark plug 130, to obtain the rotational motion of the crankshaft 23. In the shared injection mode, fuel is injected from the port injection valve 126 when air is drawn into the combustion chamber 129, and fuel is injected from the in-cylinder injection valve 127 during the intake stroke and compression stroke, and is explosively combusted by an electric spark from the spark plug 130, to obtain the rotational motion of the crankshaft 23. These injection modes are switched based on the operating state of the engine 22. Exhaust discharged from the combustion chamber 129 to an exhaust pipe 134 via an exhaust valve 133 is discharged into the outside air via a purification device 135 and a PM filter 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 PM filter 136 is formed as a porous filter from ceramics, stainless steel, or the like, and collects particulate matter (PM) such as soot in the exhaust.In place of the PM filter 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.

[0017] The operation of the engine 22 is controlled by the engine ECU 24. The engine ECU 24 includes a microcomputer having a CPU, ROM, RAM, flash memory, input / output ports, and communication ports, not shown. Signals from various sensors required for controlling the operation of the engine 22 are input to the engine ECU 24 via input ports. Examples of signals input to the engine ECU 24 include a crank angle θcr from a crank position sensor 140 that detects the rotational position of the crankshaft 23 of the engine 22, and a cooling water temperature Tw from a water temperature sensor 142 that detects the temperature of the cooling water of the engine 22. Other examples of signals input to the engine ECU 24 include 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. Other examples of the above include the throttle opening TH from a throttle valve position sensor 124a that detects the position of the throttle valve 124, the intake air amount Qa from an air flow meter 123a attached upstream of the throttle valve 124 of the intake pipe 123, the intake air temperature Ta from a temperature sensor 123t attached upstream of the throttle valve 124 of the intake pipe 123, and the surge pressure Ps from a pressure sensor 125a attached to the surge tank 125. Other examples of the above include a front air-fuel ratio AF1 from a front air-fuel ratio sensor 137 attached upstream of the purification device 135 of the exhaust pipe 134, a rear air-fuel ratio AF2 from a rear air-fuel ratio sensor 138 attached between the purification device 135 of the exhaust pipe 134 and the PM filter 136, and a differential pressure ΔP from a differential pressure sensor 136a that detects a differential pressure before and after the PM filter 136 (a differential pressure between the upstream side and the downstream side). As is well known, crank position sensor 140 comprises a timing rotor having 34 protrusions, formed by removing two consecutive protrusions that are missing teeth from the 36 protrusions spaced every 10 degrees on the outer circumference, and an electromagnetic pickup which detects the passage of the protrusions as the timing rotor rotates.

[0018] From the engine ECU 24, various control signals for controlling the operation of the engine 22 are output via an output port. Examples of signals output from the engine ECU 24 include 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, and a control signal to an ignition plug 130.

[0019] The engine ECU 24 is connected to the HVECU 70 via a communication port. 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 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. Furthermore, the engine ECU 24 calculates a PM accumulation amount Qpm as the accumulation amount of particulate matter accumulated on the PM filter 136 based on a differential pressure ΔP from the differential pressure sensor 136a, and calculates a filter temperature Tf as the temperature of the PM filter 136 based on the rotation speed Ne of the engine 22 and the load factor KL.

[0020] 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.

[0021] 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 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 rotationally driven by a motor electronic control unit (hereinafter referred to as "motor ECU") 34 controlling the switching of multiple switching elements of the inverter 32.

[0022] The motor ECU 34 includes a microcomputer having a CPU, ROM, RAM, flash memory, input / output ports, and communication ports, not shown. Signals from various sensors are input to the motor ECU 34 via the input ports. Examples of signals input to the motor ECU 34 include a rotational position θm 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 the respective phases of the motor 30. A control signal to the inverter 32 and the like are output from the motor ECU 34 via the output port. The motor ECU 34 is connected to the HVECU 70 via a communication port. The motor ECU 34 calculates the rotational speed Nm of the motor 30 based on the rotational position θm of the rotor (rotating shaft 31) of the motor 30 from the rotational position sensor 30a.

[0023] 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.

[0024] The automatic transmission 40 has a torque converter 43 and an automatic transmission 45 with, for example, six speeds. The torque converter 43 is configured as a general fluid transmission device, and transmits the power of an input shaft 41 connected to a rotating shaft 31 of the motor 30 to a transmission input shaft 44 which is an input shaft of the automatic transmission 45 with amplified torque, or transmits the torque as is without amplifying it. The automatic transmission 45 has the transmission input shaft 44, an output shaft 42 connected to driving wheels 49 via a differential gear 48, a plurality of planetary gears, and a plurality of hydraulically driven friction engagement elements (clutches, brakes). Each of the plurality of friction engagement elements has a hydraulic servo configured of a piston, a plurality of friction engagement plates (friction plates and separator plates), an oil chamber to which hydraulic oil is supplied, and the like. The automatic transmission 45 forms forward gears from 1st gear to 6th gear and reverse gears by engaging and disengaging a plurality of friction engagement elements, and transmits power between the transmission input shaft 44 and the output shaft 42. The hydraulic pressure of 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 hydraulic control device has a valve body with a plurality of oil passages formed therein, a plurality of regulator valves, a plurality of linear solenoid valves, etc. This hydraulic control device is controlled by the HVECU 70.

[0025] 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 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 supplies power from high-voltage power line 61 to low-voltage power line 63 with a voltage step-down.

[0026] Although not shown, the HVECU 70 includes a microcomputer having a CPU, a ROM, a RAM, a flash memory, an input / output port, and a communication port. Signals from various sensors are input to the HVECU 70 via the input port. Examples of signals input to the HVECU 70 include the rotation speed Nin from the rotation speed sensor 41a attached to the input shaft 41 of the automatic transmission 40, the rotation speed Nmi from the rotation speed sensor 44a attached to the transmission input shaft 44 of the automatic transmission 40, and the rotation speed Nout from the rotation speed sensor 42a attached to the output shaft 42 of the automatic transmission 40. Examples of signals input to the HVECU 70 include the voltage Vbh of the high-voltage battery 60 from a voltage sensor attached between the terminals of the high-voltage battery 60, the current Ibh of the high-voltage battery 60 from a current sensor attached to the output terminal of the high-voltage battery 60, and the voltage Vbl from a voltage sensor attached between the terminals of the low-voltage battery 62. Other examples of such signals include 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.

[0027] Various control signals are output from the HVECU 70 via an output port. Examples of signals output from the HVECU 70 include a control signal to the starter motor 25 and a control signal to the alternator 26. Examples of signals output from the HVECU 70 include a control signal to the clutch K0 and the automatic transmission 40 (hydraulic control device), and a control signal to the DC / DC converter 64. The HVECU 70 is connected to the engine ECU 24 and the motor ECU 34 via a communication port. 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.

[0028] In the hybrid vehicle 20 of the embodiment thus configured, the engine 22, the clutch K0, the motor 30, and the automatic transmission 40 are controlled by cooperative control between the HVECU 70, the engine ECU 24, and the motor ECU 34 so as to travel 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 travels 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 travels without using the power of the engine 22.

[0029] In controlling the automatic transmission 40 in the HV driving mode or the EV driving mode, the HVECU 70 first sets a target gear M* of the automatic transmission 45 based on the accelerator opening Acc and the vehicle speed V. Then, when the gear M of the automatic transmission 45 matches the target gear M*, the HVECU 70 controls the automatic transmission 45 so that the gear M is maintained. On the other hand, when the gear M and the target gear M* differ, the HVECU 70 controls the automatic transmission 45 so that the gear M matches the target gear M*.

[0030] In controlling the engine 22 and the motor 30 in the HV driving mode, the HVECU 70 first sets a required torque Tout* required for driving (required of the output shaft 42 of the automatic transmission 40) based on the accelerator opening Acc and the vehicle speed V. Next, the required torque Tout* of the output shaft 42 is divided by the rotation speed ratio Gt of the automatic transmission 40, and the value is set as the required torque Tin* of the input shaft 41. After setting the required torque Tin* of the input shaft 41 in this manner, the HVECU 70 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* of the engine 22 to the engine ECU 24 and transmits the torque command Tm* of the motor 30 to the motor ECU 34. Upon receiving the target torque Te*, the engine ECU 24 performs operation control of the engine 22 (intake air amount control, fuel injection control, ignition control, etc.) so that the engine 22 is operated at the target torque Te*. When the motor ECU 34 receives the torque command Tm*, it 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*.

[0031] In controlling the motor 30 in the EV driving mode, the HVECU 70 sets a required torque Tin* of the input shaft 41 in the same manner as in the HV driving mode, sets a torque command Tm* of the motor 30 so that the required torque Tin* is output to the input shaft 41, and transmits the torque command Tm* to the motor ECU 34. Upon receiving the torque command Tm*, 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*.

[0032] In this embodiment, the engine device corresponds to the engine 22, the clutch K0, the motor 30, the HVECU 70, the engine ECU 24, and the motor ECU .

[0033] Next, the operation of the hybrid vehicle 20 of the embodiment thus configured, particularly the operation for the initial explosion at the start of the engine 22 when the engine 22 is intermittently operated, will be described. In the embodiment, the start of the engine 22 when the engine 22 is intermittently operated is basically performed by half-engaging (slipping) the clutch K0 to output the target cranking torque Tcr* from the motor 30 to crank the engine 22, and performing the initial fuel injection and ignition (initial explosion) in the cylinder that first reaches the compression top dead center (TDC).

[0034] In this embodiment, in order to start the engine in the cylinder that first reaches the compression top dead center, the throttle valve 124 is temporarily opened just before the engine 22 is stopped and the engine is stopped within a predetermined crank angle range. The throttle valve 124 is temporarily opened just before the engine 22 is stopped in order to increase the amount of air in the cylinder that is stopped during the compression stroke. Fig. 3 is a flowchart showing an example of a start-time initial explosion process executed by the engine ECU 24 and the HVECU 70.

[0035] When the initial explosion process at start is executed, first, a process is executed to input the crank angle (stop crank angle) θstop when the engine 22 is stopped (step S100). Then, it is determined whether the electromagnetic pickup of the crank angle sensor 140 is stopped at the position of the missing tooth (step S110). Whether the electromagnetic pickup of the crank angle sensor 140 is stopped at the position of the missing tooth can be determined by the stop crank angle θstop. When it is determined that the electromagnetic pickup of the crank angle sensor 140 is stopped at the position of the missing tooth, the crank angle θcr that is the furthest from the compression top dead center of the cylinder that first reaches the compression top dead center within the range of the crank angle θcr of the missing tooth is set as the stop crank angle θstop (step S120). As described above, the timing rotor of the crank angle sensor 140 has 34 protrusions at 10 degree intervals, and two consecutive protrusions are formed as missing teeth. When the electromagnetic pickup is stopped at the position of the missing tooth, the stop crank angle θstop is unclear by the maximum missing tooth (20 degrees). For example, even if the stop crank angle θstop is BTDC40 (before TDC 40 degrees), when the electromagnetic pickup stops at the position of the missing tooth, it is unclear which position between BTDC40 and BTDC60. In this case, in the process of step S120, BTDC60, which is the farthest from the compression top dead center within the range of BTDC40 to BTDC60, is set as the stop crank angle θstop. In this way, the crank angle θcr, which is the farthest from the compression top dead center of the cylinder that first reaches the compression top dead center within the range of the missing tooth crank angle θcr, is set as the stop crank angle θstop in order to improve the startability of the engine 22 and suppress the shock of the initial explosion by assuming a case in which the amount of air in the cylinder that first reaches the compression top dead center within the range of the missing tooth crank angle θcr is the largest, and by setting the fuel injection amount Fi and the ignition timing Ti appropriate for this assumption. If it is determined in step S110 that the electromagnetic pickup of the crank angle sensor 140 has not stopped at the position of the missing tooth, the stop crank angle θstop remains the same as that input in step S100.

[0036] Next, the clutch K0 is half-engaged (slip engaged) to output the target cranking torque Tcr* from the motor 30 to start cranking of the engine 22 (step S110). This process is performed by transmitting a control signal from the HVECU 70 to a hydraulic control device (not shown) so that the clutch K0 is half-engaged (slip engaged), and transmitting the sum of the required torque Tin* required for the input shaft 41 and the target cranking torque Tcr* to the motor ECU 34 as a torque command Tm* for the motor 30. The hydraulic control device that has received the control signal adjusts the hydraulic pressure to a predetermined level so that the clutch K0 can transmit the target cranking torque Tcr* while slipping. The motor ECU 34 that has received the torque command Tm* controls the switching of a switching element (not shown) of the inverter 32 so that the torque command Tm* is output from the motor 30. In this embodiment, the target cranking torque Tcr* is a torque sufficient to cause the cylinder stopped in the compression stroke to exceed the compression top dead center, and is set based on the stop crank angle θstop and the elapsed time since the engine 22 was stopped. The reason for basing it on the stop crank angle θstop is to take into account the pressure inside the cylinder that is stopped during the compression stroke, and the reason for basing it on the time elapsed since the engine 22 was stopped is to take into account the fact that the pressure inside the cylinder that is stopped during the compression stroke decreases over time.

[0037] Then, the fuel injection amount Fi for the cylinder that first reaches the compression top dead center is set based on the elapsed time Tstop after the engine 22 is stopped, the stop crank angle θstop (position of the piston 132), and the intake manifold pressure (intake manifold pressure) Pin at the timing of closing the intake valve 128 (step S140). The reason for setting the fuel injection amount Fi based on the elapsed time Tstop after the engine 22 is stopped is that the amount of air in the cylinder that first reaches the compression top dead center decreases as the elapsed time Tstop after the engine 22 is stopped increases. The reason for setting the fuel injection amount Fi based on the stop crank angle θstop (position of the piston 132) is that the closer the position of the piston 132 is to the compression top dead center, the higher the pressure in the cylinder becomes, and the easier it is for air to escape from the piston ring. The reason for setting the fuel injection amount Fi based on the intake manifold pressure Pin is that the higher the intake manifold pressure Pin is, the greater the amount of air in the cylinder becomes. In order to obtain good startability at the initial explosion, it is preferable to set the fuel injection amount Fi for the cylinder that first reaches the compression top dead center so that it decreases as the elapsed time Tstop after the engine 22 is stopped is longer, decreases as the stop crank angle θstop (position of the piston 132) is closer to the compression top dead center, and increases as the intake manifold pressure Pin is higher. In the embodiment, the fuel injection amount Fi is set by determining in advance the relationship between the elapsed time Tstop after the engine 22 is stopped, the stop crank angle θstop (position of the piston 132), the intake manifold pressure Pin, and the fuel injection amount Fi by experiment, analysis, machine learning, or the like, and storing the relationship as a map for setting the fuel injection amount for initial explosion, and when the elapsed time Tstop, the stop crank angle θstop, and the intake manifold pressure Pin are given, the corresponding fuel injection amount Fi is derived from the map and set.

[0038] Along with the setting of the fuel injection amount Fi, the ignition timing Ti is set based on the stop crank angle θstop, the target crank torque Tcr*, and the rotation speed Nmg of the motor 30 (step S150). In the cylinder in which fuel injection and ignition are performed first, the amount of air in the cylinder increases as the stop crank angle θstop is farther from the compression top dead center (larger as BTDC). If the amount of air in the cylinder is large, the shock at the time of the initial explosion increases, so it is preferable to retard the ignition timing to reduce the shock. Therefore, in the embodiment, the ignition timing Ti is set to be retarded as the stop crank angle θstop is farther from the compression top dead center (larger as BTDC) within the range of the retard limit at which ignition is possible. As described above, the target crank torque Tcr* is set to be larger as the amount of air in the cylinder that first reaches the compression top dead center increases. Therefore, in the embodiment, the ignition timing Ti is set to be retarded as the target crank torque Tcr* is larger within the range of the retard limit at which ignition is possible. In order to start the engine 22 quickly and run using the power from the engine 22 via the clutch K0, it is necessary to control the rotation speed Ne of the engine 22 so as to quickly approximately match the rotation speed Nmg of the motor 30 and engage the clutch K0. If the rotation speed Nmg of the motor 30 is large, it takes time for the rotation speed Ne immediately after the start of the engine 22 to approximately match the rotation speed Nmg of the motor 30, so it is preferable to increase the torque of the engine 22 even at the initial explosion to increase the rotation speed Ne of the engine 22. Therefore, in this embodiment, the ignition timing Ti is set to be more advanced as the rotation speed Nmg of the motor 30 increases. For these reasons, in the embodiment, the relationship between the stop crank angle θstop, the target crank torque Tcr*, the rotation speed Nmg of the motor 30, and the ignition timing Ti is determined in advance through experiments, analysis, machine learning, etc., and stored as a map for setting the ignition timing for initial combustion. When the stop crank angle θstop, the target crank torque Tcr*, and the rotation speed Nmg of the motor 30 are given, the ignition timing Ti is set by deriving the corresponding ignition timing Ti from the map.In addition, the basic ignition timing may be set to a timing near the top dead center of the compression stroke, for example, ATDC5 (after TDC 5 degrees), by advancing or retarding the ignition timing using the stop crank angle θstop, the target crank torque Tcr*, and the rotation speed Nmg of the motor 30.

[0039] When the fuel injection amount Fi and the ignition timing Ti are set in this way, fuel is injected from the in-cylinder injection valve 127 at the timing before the compression top dead center is reached with the set fuel injection amount Fi and ignition is performed at the set ignition timing Ti (step S160), and this process ends. After that, for the cylinder that reaches the compression top dead center from the second time onwards, the fuel injection amount Fi and the ignition timing Ti are set and performed so that the rotation speed Ne of the engine 22 approaches the rotation speed Nmg of the motor 30, the engine 22 is controlled so that the rotation speed Ne of the engine 22 is synchronized with the rotation speed Nmg of the motor 30 while the clutch K0 is kept half-engaged (slip engagement) or while the clutch K0 is released from the half-engaged (slip engagement), and when the rotation speed Ne of the engine 22 is synchronized with the rotation speed Nmg of the motor 30, the clutch K0 is fully engaged and the start process of the engine 22 ends.

[0040] In the engine device mounted on the hybrid vehicle 20 of the embodiment described above, when the clutch K0 is half-engaged (slip engaged) to output the target cranking torque Tcr* from the motor 30 to start cranking the engine 22 and start the engine 22, when fuel injection and ignition (initial explosion) are performed in the cylinder that first reaches the compression top dead center, the fuel injection amount Fi is set so that it decreases as the elapsed time Tstop after the engine 22 is stopped is longer, decreases as the stop crank angle θstop (position of the piston 132) is closer to the compression top dead center, and increases as the intake manifold pressure Pin is higher. This makes it possible to more appropriately inject fuel into the cylinder that first reaches the compression top dead center, thereby improving the startability of the engine 22. In addition, when starting the engine 22, when fuel injection and ignition (initial explosion) are performed in the cylinder that first reaches the compression top dead center, the ignition timing Ti is set so that the further the stop crank angle θstop is from the compression top dead center (larger as BTDC), the greater the target crank torque Tcr* is, the greater the advance is, and the greater the rotation speed Nmg of the motor 30 is. This allows the engine 22 to be started quickly and the shock of the initial explosion to be suppressed. As a result, it is possible to achieve both good startability of the engine 22 and suppression of shock that may occur when the engine 22 is started.

[0041] In the engine device mounted on the hybrid vehicle 20 of the embodiment, when the electromagnetic pickup of the crank angle sensor 140 is stopped at the position of the missing tooth when starting the engine 22, the crank angle θcr farthest from the compression top dead center of the cylinder that reaches the compression top dead center first within the range of the crank angle θcr of the missing tooth is set as the stop crank angle θstop, and the fuel injection amount Fi and the ignition timing Ti of the cylinder that reaches the compression top dead center first are set using the set stop crank angle θstop. By setting the stop crank angle θstop in this manner, it is possible to assume the case where the amount of air in the cylinder that reaches the compression top dead center first within the range of the crank angle θcr of the missing tooth is the largest, and it is possible to set the fuel injection amount Fi and the ignition timing Ti suitable for this assumption. As a result, even when the electromagnetic pickup of the crank angle sensor 140 is stopped at the position of the missing tooth, the startability of the engine 22 can be improved and the shock of the initial explosion can be suppressed.

[0042] The hybrid vehicle 20 of the embodiment is equipped with a six-speed automatic transmission 45. However, it may be equipped with a four-speed, five-speed, eight-speed, or other automatic transmission.

[0043] The hybrid vehicle 20 of the embodiment includes the engine ECU 24, the motor ECU 34, and the HVECU 70. However, at least two of these may be integrated into one unit.

[0044] 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 may be incorporated into equipment.

[0045] 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 problem will be described below. In the embodiment, the engine 22 corresponds to the "engine", the clutch K0 corresponds to the "clutch", the motor 30 corresponds to the "motor", and the HVECU 70, the engine ECU 24, and the motor ECU 34 correspond to the "control device".

[0046] The correspondence between the main elements of the Examples and the main elements of the invention described in the Summary of the Problem column does not limit the elements of the invention described in the Summary of the Problem column, since the Examples are examples for specifically explaining the mode for implementing the invention described in the Summary of the Problem column. In other words, the interpretation of the invention described in the Summary of the Problem column should be based on the description in that column, and the Examples are merely a specific example of the invention described in the Summary of the Problem column.

[0047] Although the form for carrying out the present invention has been described above using examples, 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 without departing from the scope of the gist of the present invention. [Industrial Applicability]

[0048] The present invention can be used in the engine device manufacturing industry and the like. [Explanation of symbols]

[0049] 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 automatic transmission, 41 input shaft, 41a rotational speed sensor, 42 output shaft, 42a rotational speed sensor, 43 torque converter, 44 transmission input 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, 123t temperature sensor, 124 throttle valve, 124a throttle valve position sensor, 125 surge tank, 125a pressure sensor, 126 port injection valve, 127 in-cylinder injection valve, 128 intake valve, 129 combustion chamber, 130 spark plug, 132 piston, 133 exhaust valve, 134 exhaust pipe, 135 purification device, 135a purification catalyst, 136 PM filter, 136a differential pressure sensor, 137 front air-fuel ratio sensor, 138 rear air-fuel ratio sensor, 140 crank position sensor, 142 water temperature sensor, 144 cam position sensor, K0 clutch.

Claims

1. An engine device including an engine having an in-cylinder injection valve, a motor connected to a crankshaft of the engine via a clutch, and a control device that controls the engine, the motor, and the clutch, a crank angle sensor including a timing rotor attached to the crankshaft and having a plurality of protrusions formed on its outer periphery at equal angular intervals except for some missing teeth, and an electromagnetic pickup that detects the passage of the protrusions in response to rotation of the timing rotor, the control device, when controlling the engine, the motor, and the clutch so as to half-engage the clutch to crank the engine by the motor and to perform fuel injection and ignition for a cylinder that first reaches a compression top dead center in the engine to start the engine, sets a fuel injection amount for the cylinder that first reaches a compression top dead center based on the elapsed time since the engine was stopped and sets an ignition timing for the cylinder based on a stop crank angle when the engine was stopped, When the electromagnetic pickup is located at the missing tooth position when the engine is stopped, the control device performs at least one of a fuel injection amount correction for correcting a fuel injection amount so that combustion by ignition becomes stable, or an ignition timing correction for correcting an ignition timing so that a shock of an initial explosion is suppressed. An engine device characterized by:

2. 2. The engine device according to claim 1, when the electromagnetic pickup is located at the position of the missing tooth when the engine is stopped, the control device uses, as the stop crank angle, the crank angle that is farthest from the compression top dead center of the cylinder that first reaches the compression top dead center within the crank angle range caused by the missing tooth. Engine equipment.

Images